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Posts Tagged ‘metastasis’

Cancer Genomic Precision Therapy: Digitized Tumor’s Genome (WGSA) Compared with Genome-native Germ Line: Flash-frozen specimen and Formalin-fixed paraffin-embedded Specimen Needed

Curator: Aviva Lev-Ari, PhD, RN

Dr. Charles Swanton, Cancer Research, UK’s London Research Institute explained in his March 29, 2013 interview for Science, that the cancer treatments often fail as a result of the increasing evidence that tumors contain a heterogeneous mix of cells – tissue tagged with colored fluorescent markers for specific molecular changes sh0ws that not all cells in a tumor are the same.

http://www.sciencemag.org SCIENCE vol 339, 3/29/2013, 1543-1545

His team sequenced DNA taken from different parts of a patient’s kidney tumor, the sequence of each part was different. Severaal genetic changes were shared throughout the original tumor mass and iother tumors, or metastases, most were present in only some parts, suggesting that tumors host diverse populations of cells. some of these cells may be resistant to a treatment and continue to grow.

The findings presented below from Swanton’s Lab and from Polyak’s Lab demonstrate that intra-tumor heterogeneity as revealed by genome sequencing applied as Multiregion Sequencing might suggest that the current best practice in Oncology, of a single biopsy, must be abandoned for the sake of a new and more promising practice of multiple biopsies of the same tumor.

Kornelia Polyak’s Lab at Dana-Farber Cancer Institute, dedicated to the molecular analysis of human breast cancer

http://polyaklab.dfci.harvard.edu/

Our goals are to:

  • Better understand the molecular evolution of human breast tumors
  • Use this knowledge to improve the clinical management of breast cancer patients

Project 1: Breast tumor evolution

Modeling clonal evolution in mouse xenograft models

Cancers develop as a result of somatic evolution. Deciphering the evolutionary dynamics behind this should provide a more accurate understanding of how cancers arise and enable more intelligent approaches toward anti-cancer therapies. However, this area receives almost no experimental attention, and our understanding of clonal evolution in cancers is very rudimentary. To address this deficiency, we have developed a mouse xenograft model of human breast cancers that allows us to follow dynamics of clonal competition in genetically heterogeneous tumors.

Intratumor heterogeneity and metastasis

Metastatic dissemination of cancer cells is the most prominent cause of death due to breast cancer. Recent work in this field has established that the progression of metastatic invasion from the primary tumor to distant locations (such as bone, lungs, and brain) depends on heterogeneous interactions of cancer cells with each other and with cells composing the microenvironment. We aim to elucidate some of the factors and mechanisms that influence metastatic co-operation between cancer cells and their environment in order to fully understand the metastatic cascade and aid in the development of therapies that address this phenomenon.

Diversity in human breast tumors

Intra-tumor genetic and phenotypic diversity may predict the risk of breast cancer progression and response to treatment. To deepen our understanding of these factors, we have been defining intra-tumor diversity using immuno-FISH and ecological models in breast tumors at different progression stages (i.e., in situ, invasive, metastatic), and before and after chemotherapy or targeted (e.g., antu-Her2) treatment.

Project 2: The role of the tumor microenvironment in breast cancer

Interrogating consequences of interactions between breast carcinoma cells and tumor fibroblasts

While it is becoming increasingly apparent that interactions between carcinoma cells and tumor stroma are an essential part of tumor biology, our understanding of this crosstalk is far from complete. Using organotypic 3D culture models, we are interrogating mutual changes in transcriptome, metabolome, and phospho-proteome that result from the interaction between breast carcinoma cells and primary breast tumor-associated fibroblasts.

Myoepithelial cells and leukocytes in DCIS

The progression from in situ to invasive carcinoma is a key but poorly understood step of breast tumorigenesis, characterized by loss of the myepithelial cell layer and basement membrane. We hypothesize that the differentiation of bipotential mammary epithelial progenitors to myoepithelial cells is progressively inhibited by signals coming from tumor epithelial cells and stromal cells, such as leukocytes, leading to their eventual disappearance. Project objectives include:

  • Defining normal myoepithelial cell differentiation and its abnormalities in DCIS
  • Characterizing the role of immune cells in myoepithelial cell differentiation during breast carcinoma progression using in vivo and in vitro model systems and human breast tissue

The completion of this project will increase our understanding of the role of myoepithelial and immune cells in breast cancer, and may also provide new targets for breast cancer treatment via abnormally expressed paracrine signaling in the tumor microenvironment.

Project 3: Epigenetics in breast cancer risk and tumor development

Pregnancy study

Human epidemiological and experimental data in rodent models suggest that full-term pregnancy in early adulthood decreases the risk of estrogen receptor positive (ER+) breast cancer in post-menopausal women; however, the underlying mechanism is largely unknown. We hypothesized that the cancer-preventive effects of parity may be due to alterations in the number or properties of mammary epithelial progenitor/stem cells that are thought to be the cell-of-origin of breast cancer, rendering them less susceptible to oncogenesis. To test this hypothesis, we analyzed the relative frequency and comprehensive molecular profiles of four distinct cell types (CD24+ luminal, CD10+ myoepithelial, lin-/CD24-/CD44+ progenitor-enriched, and stromal fibroblasts) isolated from normal breast tissue of premenopausal nulliparous and parous women. Based on the comprehensive analysis of gene expression, DNA, and histone H3 K27 trimethylation profiles of these cell types, we determined that the most significant changes occurred in lin-/CD24-/CD44+ progenitor-enriched cells. The activity of many genes and pathways involved in development, differentiation, and cell cycle regulation are decreased in parous women that may contribute to their decreased breast cancer risk. We also identified a parity-associated gene signature that predicted clinical outcome in breast cancer patients diagnosed with ER+ tumors.

The role of DNA methylation in mouse mammary gland development

The mouse mammary gland is a useful model system for understanding factors that regulate mammary development. We are pursuing molecular characterization of the different cell types that comprise the mammary epithelium of the mouse. Based on the varying proportional distributions we observe in the mature, progenitor, and stem cell populations of the mammary gland during different life stages, we seek to understand the underlying molecular cues that maintain cell type identities and direct cellular distribution changes by studying the gene expression and epigenetic properties of distinct cell populations during puberty and pregnancy, stages during which there is dramatic tissue remodeling in the mammary gland. Furthermore, with the use of in vitro and in vivo mouse models for the functional characterization of maintenance DNA methylation, we are characterizing potential active roles of this important epigenetic mark in directing cell fate in the mammary gland.

Histone modifying enzymes as new therapeutic targets

The differentiation of normal stem cells and the development of normal tissue are controlled by epigenetic mechanisms. Abnormalities in these processes play a role in the initiation and progression of tumors and intra-tumor diversification of cancer cells. A number of histone-modifying genes were found to be mutated in breast and other cancers, implying that these genes may represent novel therapeutic targets and biomarkers. We have recently reported the characterization of cell-type specific patterning of histone and DNA methylation in normal breast tissues. We developed modified chromatin immunoprecipitation combined with high-throughput sequencing (ChIP-Seq) protocol which enables us to investigate the epigenetic status genome-wide, using limited numbers of cells purified from human breast tissue samples. Currently, we are using various genomic profiling and functional studies to validate several histone demethylases as potential therapeutic targets in breast cancer.

Determinants of basal-like and luminal breast cancer cell phenotypes

Basal-like and luminal breast tumors have distinct molecular profiles and clinical behavior, yet the mechanisms underlying these differences are poorly defined. We investigated the potential role of genetic factors in determining these distinct phenotypes and their inheritance pattern by generating somatic cell fusions between basal-like and luminal breast cancer cells and analyzing their molecular profiles and functional characteristics. Based on the molecular profiles, we identified candidate key transcriptional and epigenetic determinants of basal-like and luminal cell phenotypes. We are further characterizing these genes using functional genomics approaches.

Project 4: Emerging therapeutic targets in breast cancer

Amplified kinases and novel targets in breast cancer

Kinase inhibitors have been one of the most successful drugs for cancer treatments, but their efficacies in patients are still not satisfactory. We have identified novel kinases amplified in breast cancer, and are using functional genomic approaches to validate them as therapeutic targets.

Novel therapeutic targets in triple negative breast cancer

We have conducted an shRNA cell viability screen of 1,576 candidate genes differentially expressed between CD44+CD24- stem cell-like and CD44-CD24+ more differentiated luminal breast cancer cells. These shRNA were further tested across 14 breast cancer cell lines, thereby generating a list of 15 genes of high interest as candidate therapeutic targets against CD44+CD24- cells, including IL6, CXCL3, PTGIS, IGFBP7, PFKFB3 and HAS1. We have followed up and validated the Il6/Jak2/Stat3 signaling pathway in further detail and demonstrated that JAK2 inhibitors may effectively inhibit the growth of breast tumors that have activation of this pathway as determined based on expression of phospho-Stat3 (pStat3). Based on our preclinical data, a clinical trial testing the efficacy of Jak2 inhibitors in pStat3+ breast tumors (enriched in BLBC) is being initiated at DFCI. More recently we also found that a high fraction of inflammatory breast cancer (IBC) are also positive for pStat3, and thus, may respond to JAK kinase inhibition. Besides the JAK/Stat3 pathway, other potentially promising targets include CXCR2, PTGIS, and HAS1. We are conducting preclinical studies validating these genes and their combination as potential new therapeutic strategies in breast cancer.

 

Swanton’s results was published in NEJM on March 8, 2012. 143 citations followed by year end.

http://www.med.upenn.edu/timm/documents/Minn_NEJMTimmMainarticle.pdf

Intratumor Heterogeneity and Branched Evolution Revealed by Multiregion Sequencing

Marco Gerlinger, M.D., Andrew J. Rowan, B.Sc., Stuart Horswell, M.Math., James Larkin, M.D., Ph.D.,

David Endesfelder, Dip.Math., Eva Gronroos, Ph.D., Pierre Martinez, Ph.D., Nicholas Matthews, B.Sc.,

Aengus Stewart, M.Sc., Patrick Tarpey, Ph.D., Ignacio Varela, Ph.D., Benjamin Phillimore, B.Sc., Sharmin Begum, M.Sc.,

Neil Q. McDonald, Ph.D., Adam Butler, B.Sc., David Jones, M.Sc., Keiran Raine, M.Sc., Calli Latimer, B.Sc.,

Claudio R. Santos, Ph.D., Mahrokh Nohadani, H.N.C., Aron C. Eklund, Ph.D., Bradley Spencer-Dene, Ph.D.,

Graham Clark, B.Sc., Lisa Pickering, M.D., Ph.D., Gordon Stamp, M.D., Martin Gore, M.D., Ph.D., Zoltan Szallasi, M.D.,

Julian Downward, Ph.D., P. Andrew Futreal, Ph.D., and Charles Swanton, M.D., Ph.D.

Abstr act

From the Cancer Research UK London

Research Institute (M. Gerlinger, A.J.R.,

S.H., D.E., E.G., P.M., N.M., A.S., B.P.,

S.B., N.Q.M., C.R.S., B.S.-D., G.C., G.S.,

J.D., C.S.), Royal Marsden Hospital Department

of Medicine ( J.L., M.N., L.P.,

G.S., M. Gore), Wellcome Trust Sanger

Institute (P.T., I.V., A.B., D.J., K.R., C.L.,

P.A.F.), Barts Cancer Institute at the

Barts and the London School of Medicine

and Dentistry (M. Gerlinger), and the University

College London Cancer Institute

(C.S.) — all in London; the Technical University

of Denmark, Lyngby (A.C.E., Z.S.);

and Harvard Medical School, Boston (Z.S.).

Address reprint requests to Dr. Swanton at

the Cancer Research UK London Research

Institute, Translational Cancer Therapeutics

Laboratory, 44 Lincoln’s Inn Fields,

London WC2A 3LY, United Kingdom, or

at charles.swanton@cancer.org.uk.

Drs. Gerlinger, Larkin, Gronroos, Martinez,

and Swanton and Mr. Rowan, Mr. Horswell,

Mr. Endesfelder, Mr. Matthews, and

Mr. Stewart contributed equally to this

article.

N Engl J Med 2012;366:883-92.

Copyright © 2012 Massachusetts Medical Society.

Background

Intratumor heterogeneity may foster tumor evolution and adaptation and hinder

personalized-medicine strategies that depend on results from single tumor-biopsy

samples.

Methods

To examine intratumor heterogeneity, we performed exome sequencing, chromosome

aberration analysis, and ploidy profiling on multiple spatially separated samples obtained

from primary renal carcinomas and associated metastatic sites. We characterized

the consequences of intratumor heterogeneity using immunohistochemical analysis,

mutation functional analysis, and profiling of messenger RNA expression.

Results

Phylogenetic reconstruction revealed branched evolutionary tumor growth, with 63 to

69% of all somatic mutations not detectable across every tumor region. Intratumor

heterogeneity was observed for a mutation within an autoinhibitory domain of the

mammalian target of rapamycin (mTOR) kinase, correlating with S6 and 4EBP

phosphorylation in vivo and constitutive activation of mTOR kinase activity in vitro.

Mutational intratumor heterogeneity was seen for multiple tumor-suppressor genes

converging on loss of function; SETD2, PTEN, and KDM5C underwent multiple distinct

and spatially separated inactivating mutations within a single tumor, suggesting

convergent phenotypic evolution. Gene-expression signatures of good and poor prognosis

were detected in different regions of the same tumor. Allelic composition and

ploidy profiling analysis revealed extensive intratumor heterogeneity, with 26 of 30 tumor

samples from four tumors harboring divergent allelic-imbalance profiles and with

ploidy heterogeneity in two of four tumors.

Conclusions

Intratumor heterogeneity can lead to underestimation of the tumor genomics landscape

portrayed from single tumor-biopsy samples and may present major challenges to

personalized-medicine and biomarker development. Intratumor heterogeneity, associated

with heterogeneous protein function, may foster tumor adaptation and therapeutic

failure through Darwinian selection. (Funded by the Medical Research Council

and others.)

n engl j med 366;10 nejm.org march 8, 2012

Sci Transl Med 28 March 2012:
Vol. 4, Issue 127, p. 127ps10
Sci. Transl. Med. DOI: 10.1126/scitranslmed.3003854
  • PERSPECTIVE

TUMOR HETEROGENEITY

Intratumor Heterogeneity: Seeing the Wood for the Trees

  1. Timothy A. Yap1*,
  2. Marco Gerlinger2,3*,
  3. P. Andrew Futreal4,
  4. Lajos Pusztai5 and
  5. Charles Swanton2,6†

+Author Affiliations


  1. 1Department of Medicine, Royal Marsden NHS Foundation Trust, Downs Road, Sutton, Surrey SM2 5PT, UK.

  2. 2Translational Cancer Therapeutics Laboratory, Cancer Research UK London Research Institute, 44 Lincoln’s Inn Fields, London WC2A 3LY, UK.

  3. 3Barts Cancer Institute, Barts and The London School of Medicine and Dentistry, Charterhouse Square, London EC1M 6BQ, UK.

  4. 4Wellcome Trust Sanger Institute, Hinxton, Cambridge CB10 1SA, UK.

  5. 5Department of Breast Medical Oncology, Division of Cancer Medicine, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.

  6. 6University College London Cancer Institute, Huntley Street, London WC1E 6BT, UK.

  7. *These authors contributed equally to this work.
  1. Corresponding author. E-mail: charles.swanton@cancer.org.uk

ABSTRACT

Most advanced solid tumors remain incurable, with resistance to chemotherapeutics and targeted therapies a common cause of poor clinical outcome. Intratumor heterogeneity may contribute to this failure by initiating phenotypic diversity enabling drug resistance to emerge and by introducing tumor sampling bias. Envisaging tumor growth as a Darwinian tree with the trunk representing ubiquitous mutations and the branches representing heterogeneous mutations may help in drug discovery and the development of predictive biomarkers of drug response.

Citation: T. A. Yap, M. Gerlinger, P. A. Futreal, L. Pusztai, C. Swanton, Intratumor Heterogeneity: Seeing the Wood for the Trees. Sci. Transl. Med. 4, 127ps10 (2012).

THE EDITORS SUGGEST THE FOLLOWING RELATED RESOURCES ON SCIENCE SITE

In Science Translational Medicine

  • EDITORIAL:CANCERWinning the War: Science Parkour

    • Bert Vogelstein and
    • Kenneth W. Kinzler

    Sci Transl Med 28 March 2012 4:127ed2

THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:

  • Development of Therapeutic Combinations Targeting Major Cancer Signaling PathwaysJCO 20 April 2013 31:1592-1605
  • A tale of two approaches: complementary mechanisms of cytotoxic and targeted therapy resistance may inform next-generation cancer treatmentsCarcinogenesis 1 April 2013 34:725-738
  • Intratumor heterogeneity in human glioblastoma reflects cancer evolutionary dynamicsProc. Natl. Acad. Sci. USA 5 March 2013 110:4009-4014
  • Accelerating Cancer Therapy Development: The Importance of Combination Strategies and Collaboration. Summary of an Institute of Medicine WorkshopClin. Cancer Res. 15 November 2012 18:6101-6109
  • Pluripotent Stem Cell-Based Cancer Therapy: Promise and ChallengesSci Transl Med 28 March 2012 4:127ps9

VIEW VIDEO

Topol on the Cancer Clinic of the Future

Hello. I’m Dr. Eric Topol, director of the Scripps Translational Science Institute and Editor-in-Chief of Medscape. In this series, The Creative Destruction of Medicine, named for the book I wrote, I am trying to zoom in on critical aspects of how the digital world can create better healthcare.

Cancer care is rapidly changing, if we think about where it was some years ago as it was really beautifully archived in a book by Sid Mukherjee, MD, The Emperor of All Maladies,[1] and to where we can go in the future. Just launched recently, for example, was MD Anderson Cancer Center’s Moon Shots program in cancer care.[2] The Moon Shots program is perhaps, because of genomics, digitizing the genome of the tumor, comparing it with the genome-native germ line. This gives us an opportunity we never had before.

So what is the cancer clinic of the future going to look like, because it’s just starting to get developed today? For example, when we have an individual presenting for a new diagnosis of cancer, we have to move away from fine-needle aspiration and minimal tissue; we need real tissue to be able to process it properly. Not only do we need the formalin-fixed paraffin-embedded (FFPE) specimen, but we also need another type of FF — that is, flash-frozen specimens so that we can then whole-genome sequence this tissue.

Now, when that is done at the primary diagnosis and done within hours and analyzed with the appropriate software algorithms, we could get the driver mutations nailed within 24 hours from the diagnosis. This can set up remarkably precise therapy that can be given to the patient on the basis of that individual’s tumor. There are no 2 different cancers that are the same anywhere. Just like there are no 2 individuals who have the same DNA, that’s the same for a tumor.

One of the issues that we have to confront is that there’s a lot of intratumor heterogeneity. We need multiple samples to sequence from the tumor, and if there’s already a metastatic lesion, we need a sample of that as well. Multiple sequencing, frozen tissue, genome-driven guided therapy — right from the get-go — is what we need. That’s not what we have today, but that’s where we can go in the future of cancer genomic medicine. It’s really an exciting opportunity. It has to be validated.

The cancer drugs that are used today are remarkably expensive, and what’s fascinating is to see — and this is a recurrent theme — is that a drug being used, for example, for renal carcinoma can also be used for leukemia. There was a classic 3-part article on the front page of the New York Times [3] that exemplified some of the stories along those lines.

It’s a story about mutations — a war on mutations, not a war on cancer — and this type of cancer clinic in the future can take us there but there’s going to have to be a whole different look with respect to the way that we take samples of the tumor. We need much more tissue, and to use frozen tissue so that we don’t have to bootstrap the FFPE (that paraffin-embedded specimen) and only get a couple of hundred genes or coding elements, but in fact get a whole genome from the flash-frozen specimen. That’s really important, and we have to move in that direction — get more tissue in order to account for the heterogeneity that we know exists. And we have to do deep sequencing of that frozen tissue in order to get the driver mutations identified, and also be able to anticipate where relapses can occur downstream.

That is precision therapy. This exemplifies the future of cancer genomic medicine, and it will be really interesting to see how that plays out in these cancer clinics of the future.

Thanks so much for joining us for this segment, and stay tuned for more from The Creative Destruction of Medicine series.

References

  1. Mukherjee S. The Emperor of All Maladies: A Biography of Cancer. New York: Scribner; 2010. The 2011 Pulitzer Prize Winners: General Nonfiction. http://www.pulitzer.org/works/2011-General-Nonfiction. Accessed March 5, 2013.
  2. University of Texas MD Anderson Center. Moon Shots program. http://cancermoonshots.org/. Accessed March 5, 2013.
  3. Kolata G. In treatment for leukemia, glimpses of the future. New York Times. July 7, 2012.http://www.nytimes.com/2012/07/08/health/in-gene-sequencing-treatment-for-leukemia-glimpses-of-the-future.html?
  4. pagewanted=all&_r=0. Accessed March 5, 2013.

SOURCE:

http://www.medscape.com/viewarticle/780424?src=emailthis

Charles Swanton Publications

London Research Institute

44 Lincoln’s Inn Fields
London
WC2A 3LY
United Kingdom

Emailcharles.swanton@cancer.org.uk
WebLab website

Primary research papers

The following publications have been supported by Cancer Research UK funding for this researcher.

2010

From genomic landscapes to personalized cancer management-is there a roadmap?
Swanton C;Caldas C
Ann N Y Acad Sci 2010; 1210 ( ):34-44.
PubMed;  DOI: 10.1111/j.1749-6632.2010.05776.x.

Minimising Immunohistochemical False Negative ER Classification Using a Complementary 23 Gene Expression Signature of ER Status
Li QY;Eklund AC;Juul N;Haibe-Kains B;Workman CT;Richardson AL;Szallasi Z;Swanton C
PLoS ONE 2010; (11):e15031.
DOI: 10.1371/journal.pone.0015031.

How Darwinian models inform therapeutic failure initiated by clonal heterogeneity in cancer medicine
Gerlinger M;Swanton C
Br J Cancer 2010; 103 (8):1139-1143.
UKPubMed (open access);  PubMed;  DOI: 10.1038/sj.bjc.6605912.

Anti-cancer drug resistance: Understanding the mechanisms through the use of integrative genomics and functional RNA interference
Tan DSW;Gerlinger M;Teh BT;Swanton C
Eur J Cancer 2010; 46 (12):2166-2177.
PubMed;  DOI: 10.1016/j.ejca.2010.03.019.

A retrospective analysis of clinical outcome of patients with chemo-refractory metastatic breast cancer treated in a single institution phase I unit
Brunetto AT;Sarker D;Papadatos-Pastos D;Fehrmann R;Kaye SB;Johnston S;Allen M;De Bono JS;Swanton C
Br J Cancer 2010; 103 (5):607-612.
PubMed;  DOI: 10.1038/sj.bjc.6605812.

FKBPL Regulates Estrogen Receptor Signaling and Determines Response to Endocrine Therapy
McKeen HD;Byrne C;Jithesh PV;Donley C;Valentine A;Yakkundi A;O’Rourke M;Swanton C;McCarthy HO;Hirst DG;Robson T
Cancer Res 2010; 70 (3):1090-1100.
DOI: 10.1158/0008-5472.CAN-09-2515.

Prognostic and Predictive Biomarkers in Resected Colon Cancer: Current Status and Future Perspectives for Integrating Genomics into Biomarker Discovery
Tejpar S;Bertagnolli M;Bosman F;Lenz HJ;Garraway L;Waldman F;Warren R;Bild A;Collins-Brennan D;Hahn H;Harkin DP;Kennedy R;Ilyas M;Morreau H;Proutski V;Swanton C;Tomlinson I;Delorenzi M;Fiocca R;Van Cutsem E;Roth A
Oncologist 2010; 15 (4):390-404.
DOI: 10.1634/theoncologist.2009-0233.

Assessment of an RNA interference screen-derived mitotic and ceramide pathway metagene as a predictor of response to neoadjuvant paclitaxel for primary triple-negative breast cancer: a retrospective analysis of five clinical trials
Juul N;Szallasi Z;Eklund AC;Li QY;Burrell RA;Gerlinger M;Valero V;Andreopoulou E;Esteva FJ;Symmans WF;Desmedt C;Haibe-Kains B;Sotiriou C;Pusztai L;Swanton C
Lancet Oncol 2010; 11 (4):358-365.
PubMed;  DOI: 10.1016/S1470-2045(10)70018-8.

2009

RNAi-mediated functional analysis of pathways influencing cancer cell drug resistance
Lee AJX;Kolesnick R;Swanton C
Expert Rev Mol Med 2009; 11 ():e15.
PubMed;  DOI: 10.1017/S1462399409001070.

Advances in personalized therapeutics in non-small cell lung cancer: 4q12 amplification, PDGFRA oncogene addiction and sunitinib sensitivity
Swanton C;Burrell RA
Cancer Biol Ther 2009; (21):2051-2053.
PubMed;

Chromosomal instability A composite phenotype that influences sensitivity to chemotherapy
McClelland SE;Burrell RA;Swanton C
Cell Cycle 2009; (20):3262-3266.
PubMed;

Genetic prognostic and predictive markers in colorectal cancer
Walther A;Johnstone E;Swanton C;Midgley R;Tomlinson I;Kerr D
Nat Rev Cancer 2009; (7):489-499.
PubMed;

Chromosomal instability determines taxane response
Swanton C;Nicke B;Schuett M;Eklund AC;Ng C;Li QY;Hardcastle T;Lee A;Roy R;East P;Kschischo M;Endesfelder D;Wylie P;Kim SN;Chen JG;Howell M;Ried T;Habermann JK;Auer G;Brenton JD;Szallasi Z;Downward J
Proc Natl Acad Sci U S A 2009; 106 (21):8671-8676.
UKPubMed (open access);  PubMed;  DOI: 10.1073/pnas.0811835106.

Molecular classification of solid tumours: towards pathway-driven therapeutics
Swanton C;Caldas C
Br J Cancer 2009; 100 (10):1517-1522.
PubMed;

2008

Epothilones and new analogues of the microtubule modulators in taxane-resistant disease
Harrison M;Swanton C
Expert Opin Invest Drugs 2008; 17 (4):523-546.
PubMed;

Targeting Polo-Like Kinase: Learning Too Little Too Late?
Olmos D;Swanton C;de Bono J
J Clin Oncol 2008; 26 (34):5497-5499.
PubMed;

Concordance of exon array and real-time PCR assessment of gene expression following cancer cell cytotoxic drug exposure
Lee AJX;East P;Pepper S;Nicke B;Szallasi Z;Eklund AC;Downward J;Swanton C
Cell Cycle 2008; (24):3947-3948.
PubMed;

Functional genomic analysis of drug sensitivity pathways to guide adjuvant strategies in breast cancer
Swanton C;Szallasi Z;Brenton JD;Downward J
Breast Cancer Res 2008; 10 (5):214.
UKPubMed (open access);  PubMed;  DOI: 10.1186/bcr2159.

Unraveling the complexity of endocrine resistance in breast cancer by functional genomics
Swanton C;Downward J
Cancer Cell 2008; 13 (2):83-85.
PubMed;

 

146 Publications on PubMed by Polyak’s Lab

 

Other related articles on this Open Access Online Scientific Journal include the following:

Issues in Personalized Medicine in Cancer: Intratumor Heterogeneity and Branched Evolution Revealed by Multiregion Sequencing

Stephen J. Williams, Ph.D. 4/10/2013

http://pharmaceuticalintelligence.com/2013/04/10/issues-in-personalized-medicine-in-cancer-intratumor-heterogeneity-and-branched-evolution-revealed-by-multiregion-sequencing/

Pfizer’s Kidney Cancer Drug Sutent Effectively caused REMISSION to Adult Acute Lymphoblastic Leukemia (ALL)

Aviva Lev-Ari, PhD, RN, 7/10/2012

http://pharmaceuticalintelligence.com/2012/07/10/pfizers-kidney-cancer-drug-sutent-effectively-caused-remission-to-adult-acute-lymphoblastic-leukemia-all/

On Tumor and mutations

http://pharmaceuticalintelligence.com/?s=tumor+mutations

On ‘genomics mutations’

http://pharmaceuticalintelligence.com/?s=genomics+mutations

On ‘cancer sequencing’

http://pharmaceuticalintelligence.com/?s=cancer+sequencing

 On Metastasis

Read Full Post »

microRNA Biomarker

Reporter: Larry H Bernstein, MD, FCAP

MicroRNA Molecule May Serve as Biomarker

miRNA molecule called miR-7 decreased in highly metastatic cancer stem-like cells.
February 18, 2013
Researchers have identified two molecules that could potentially serve as biomarkers in

MicroRNAs are involved in

  • tumor initiation and
  • progression, and
  • may play a role in metastasis, particularly in relation to
  • cancer stem-like cells.
miR-7 is a metastasis

  • suppressor in cancer stem-like cells, and when they
  • increased expression of miR-7 in cancer stem-like cells from
    • it suppressed their metastatic properties.

miR-7 suppressed ………….expression of KLF4.
However, miR-7 significantly suppressed the ability of cancer stem-like cells to metastasize to the brain but not the bone.

A gram illustrating the disctinction between c...

A gram illustrating the disctinction between cancer stem cell targeted (above) and conventional (below) cancer therapies (Photo credit: Wikipedia)

Related articles

 

Read Full Post »

Reporter: Prabodh Kandala, PhD

Screen Shot 2021-07-19 at 6.21.55 PM

Word Cloud By Danielle Smolyar

A typical cancer cell has thousands of mutations scattered throughout its genome and hundreds of mutated genes. However, only a handful of those genes, known as drivers, are responsible for cancerous traits such as uncontrolled growth. Cancer biologists have largely ignored the other mutations, believing they had little or no impact on cancer progression.

But a new study from MIT, Harvard University, the Broad Institute and Brigham and Women’s Hospital reveals, for the first time, that these so-called passenger mutations are not just along for the ride. When enough of them accumulate, they can slow or even halt tumor growth.

The findings, reported in this week’sProceedings of the National Academy of Sciences, suggest that cancer should be viewed as an evolutionary process whose course is determined by a delicate balance between driver-propelled growth and the gradual buildup of passenger mutations that are damaging to cancer, says Leonid Mirny, an associate professor of physics and health sciences and technology at MIT and senior author of the paper.

Furthermore, drugs that tip the balance in favor of the passenger mutations could offer a new way to treat cancer, the researchers say, beating it with its own weapon — mutations. Although the influence of a single passenger mutation is minuscule, “collectively they can have a profound effect,” Mirny says. “If a drug can make them a little bit more deleterious, it’s still a tiny effect for each passenger, but collectively this can build up.”

Lead author of the paper is Christopher McFarland, a graduate student at Harvard. Other authors are Kirill Korolev, a Pappalardo postdoctoral fellow at MIT, Gregory Kryukov, a senior computational biologist at the Broad Institute, and Shamil Sunyaev, an associate professor at Brigham and Women’s.

Power struggle

Cancer can take years or even decades to develop, as cells gradually accumulate the necessary driver mutations. Those mutations usually stimulate oncogenes such as Ras, which promotes cell growth, or turn off tumor-suppressing genes such as p53, which normally restrains growth.

Passenger mutations that arise randomly alongside drivers were believed to be fairly benign: In natural populations, selection weeds out deleterious mutations. However, Mirny and his colleagues suspected that the evolutionary process in cancer can proceed differently, allowing mutations with only a slightly harmful effect to accumulate.

To test this theory, the researchers created a computer model that simulates cancer growth as an evolutionary process during which a cell acquires random mutations. These simulations followed millions of cells: every cell division, mutation and cell death.

They found that during the long periods between acquisition of driver mutations, many passenger mutations arose. When one of the cancerous cells gains a new driver mutation, that cell and its progeny take over the entire population, bringing along all of the original cell’s baggage of passenger mutations. “Those mutations otherwise would never spread in the population,” Mirny says. “They essentially hitchhike on the driver.”

This process repeats five to 10 times during cancer development; each time, a new wave of damaging passengers is accumulated. If enough deleterious passengers are present, their cumulative effects can slow tumor growth, the simulations found. Tumors may become dormant, or even regress, but growth can start up again if new driver mutations are acquired. This matches the cancer growth patterns often seen in human patients.

“Cancer may not be a sequence of inevitable accumulation of driver events, but may be actually a delicate balance between drivers and passengers,” Mirny says. “Spontaneous remissions or remissions triggered by drugs may actually be mediated by the load of deleterious passenger mutations.”

When they analyzed passenger mutations found in genomic data taken from cancer patients, the researchers found the same pattern predicted by their model — accumulation of large quantities of slightly deleterious mutations.

Tipping the balance

In computer simulations, the researchers tested the possibility of treating tumors by boosting the impact of deleterious mutations. In their original simulation, each deleterious passenger mutation reduced the cell’s fitness by about 0.1 percent. When that was increased to 0.3 percent, tumors shrank under the load of their own mutations.

The same effect could be achieved in real tumors with drugs that interfere with proteins known as chaperones, Mirny suggests. After proteins are synthesized, they need to be folded into the correct shape, and chaperones help with that process. In cancerous cells, chaperones help proteins fold into the correct shape even when they are mutated, helping to suppress the effects of deleterious mutations.

Several potential drugs that inhibit chaperone proteins are now in clinical trials to treat cancer, although researchers had believed that they acted by suppressing the effects of driver mutations, not by enhancing the effects of passengers.

In current studies, the researchers are comparing cancer cell lines that have identical driver mutations but a different load of passenger mutations, to see which grow faster. They are also injecting the cancer cell lines into mice to see which are likeliest to metastasize.

Ref:

Massachusetts Institute of Technology (2013, February 4). Some cancer mutations slow tumor growth. ScienceDaily. Retrieved February 4, 2013, from http://www.sciencedaily.com­/releases/2013/02/130204154011.htm

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Author: Tilda Barliya PhD

Metastasis, the spread of cancer cells from a primary tumour to seed secondary tumours in distant sites, is one of the greatest challenges in cancer treatment today. For many patients, by the time cancer is detected, metastasis  has already occurred. Over 80% of patients diagnosed  with lung cancer, for example, present with metastatic  disease. Few patients with metastatic cancer are cured by surgical intervention, and other treatment modalities are limited. Across all cancer types, only one in five patients diagnosed with metastatic cancer will survive more than 5 years. (1,2).

Metastatic Cancer 

  • Metastatic cancer is cancer that has spread from the place where it first started to another place in the body.
  • Metastatic cancer has the same name and same type of cancer cells as the original cancer.
  • The most common sites of cancer metastasis are the lungs, bones, and liver.
  • Treatment for metastatic cancer usually depends on the type of cancer and the size, location, and number of metastatic tumors.

How do cancer cells spread (3)

  • Local invasion: Cancer cells invade nearby normal tissue.
  • Intravasation: Cancer cells invade and move through the walls of nearby lymph vessels or blood vessels.
  • Circulation: Cancer cells move through the lymphatic system and the bloodstream to other parts of the body.

The ability of a cancer cell to metastasize successfully depends on its individual properties; the properties of the noncancerous cells, including immune system cells, present at the original location; and the properties of the cells it encounters in the lymphatic system or the bloodstream and at the final destination in another part of the body. Not all cancer cells, by themselves, have the ability to metastasize. In addition, the noncancerous cells at the original location may be able to block cancer cell metastasis. Furthermore, successfully reaching another location in the body does not guarantee that a metastatic tumor will form. Metastatic cancer cells can lie dormant (not grow) at a distant site for many years before they begin to grow again, if at all.

Although cancer therapies are improving, many drugs are not reaching the sites of metastases, and doubt  remains over the efficacy of those that do. Methods  that are effective for treating large, well-vascularized tumours may be inadequate when dealing with small clusters of disseminated malignant cells.

We expect that the expanding capabilities of nanotechnology, especially in targeting, detection and particle trafficking, will enable  novel approaches to treat cancers even after metastatic dissemination.

 

Lymph nodes, which are linked by lymphatic vessels, are distributed throughout the body and have an integral role in the immune response. Dissemination of cancer cells through the lymph network is thought to be an important route for metastatic spread. Tumor proximal lymph nodes are often the first site of metastases, and the presence of lymph node metastases signifies further metastatic spread and poor patient survival.

As such, lymph nodes have been targeted using cell-based nanotechnologies

Lymph nodes are small, bean-shaped organs that act as filters along the lymph fluid channels. As lymph fluid leaves the organ (such as breast, lung etc) and eventually goes back into the bloodstream, the lymph nodes try to catch and trap cancer cells before they reach other parts of the body. Having cancer cells in the lymph nodes suggests an increased risk of the cancer spreading. It is thus very important to evaluate the involvement of lymph nodes when choosing the best possible treatment for the patient.

Although current mapping methods are available such as CT and MRI scans, PET scan, Endobronchial Ultrasound, Mediastinoscopy and lymph node biopsy, sentinel lymph node (SLN) mapping and nodal treatment in lung cancer remain inadequate for routine clinical use. 

Certain characteristics are associated with preferential (but not exclusive) nanoparticle trafficking to lymph nodes following intravenous administration.

Targeting is often an indirect process, as receptors on the surface of leukocytes bind nanoparticles and transfer them to lymph nodes as part of a normal immune response. Several strategies have been used to enhance nanoparticle uptake by leukocytes in circulation. Coating iron-oxide nanoparticles with carbohydrates, such as dextran, results in the increased accumulation of these nanoparticles in lymph nodes. Conjugating peptides and antibodies, such as immunoglobulin G (IgG), to the particle surface also increases their accumulation in the lymphatic network. In general, negatively charged particles are taken up at faster rates than positively charged or uncharged particles. Conversely, ‘stealth’ polymers, such as polyethylene glycol (PEG), on the surface of nanoparticles, can inhibit uptake by leukocytes, thereby reducing accumulation in the lymph nodes.

Lymph node targeting may be achieved by other routes of administration. Tsuda and co-workers reported that non-cationic particles with a size range of 6–34nm, when introduced to the lungs (intrapulmonary administration), are trafficked rapidly (<1 hour) to local lymph nodes. Administering particles <80 nm in size subcutaneously also results in trafficking to lymph nodes. Interestingly, some studies have indicated that non-pegylated particles exhibit enhanced accumulation in the lymphatics and that pegylated particles tend to appear in the circulation several hours after administration.

Over the last twenty years, sentinel lymph node (SLN) imaging has revolutionized the treatment of several malignancies, such has melanoma and breast cancer, and has the potential to drastically improve treatment in other malignancies, including lung cancer. Several attempts at developing an easy, reliable, and effective method for SLN mapping in lung cancer have been unsuccessful due to unique difficulties inherent to the lung and to operating in the thoracic cavity.

An inexpensive method offering rapid, intraoperative identification of SLNs, with minimal risk to both patient and provider, would allow for improved staging in patients. This, in turn, would permit better selection of patients for adjuvant therapy, thus reducing morbidity in those patients for whom adjuvant treatment is inappropriate, and ensuring that those who need this added therapy actually receive it. (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3109504/)

Current methods for SLN identification involve the use of radioactivity-guided mapping with technetium-99m sulfur colloid and/or visual mapping using vital blue dyes. Unfortunately these methods can be inadequate for SLN mapping in non-small cell lung cancer (NSCLC) The use of vital blue dyes is limited in vivo by poor visibility, particularly in the presence of anthracotic mediastinal nodes, thereby decreasing the signal-to-background ratio (SBR) that enables nodal detection. Similarly, results with technetium-99m sulfur colloid have been mixed when used in the thoracic cavity, where hilar structures and aberrant patterns of lymphatic drainage make detection more difficult.

Although Nomori et al. have reported an 83% nodal identification rate following a preoperative injection of technetium-99 colloid, there is an associated increased risk of pneumothorax and bleeding with this method. Further, the recently completed CALGB 140203 multicenter Phase 2 trial investigating the use of intraoperative technetium-99m colloid found an identification rate of only 51% with this technique.  Clearly a technology with greater accuracy, improved SBR, and less potential risk to surgeon and patient would be welcome in the field of thoracic oncology.

Near-infrared (NIR) fluorescence imaging has the potential to meet this difficult challenge.

Near-Infrared Light

NIR light is defined as that within the wavelength range of 700 to 1000 nm. Although NIR light is invisible to the naked eye, it can be thought of as “redder” than UV and visible light.

  • Absorption, scatter, and autofluorescence are all significantly reduced at redder wavelengths. For instance, Hemoglobin, water, lipids, and other endogenous chromophores, such as melanin, have their lowest absorption within the NIR spectrum, which permits increased photon depth penetration into tissues
  • In addition, imaging can also be affected by photon scatter, which describes the reflection and/or deflection of light when it interacts with tissue. Scatter, on an absolute scale, is often ten-times higher than absorption. However, the two major types of scatter, Mie and Rayleigh, are both reduced in the NIR, making the use of NIR wavelengths especially important for the reduction of photon attenuation.
  • living tissue has extremely high “autofluorescence” in the UV and visible wavelength ranges due to endogenous fluorophores, such as NADH and the porphyrins. Therefore, UV/visible fluorescence imaging of the intestines, bladder, and gallbladder is essentially precluded. However, in the NIR spectrum, autofluorescence is extremely low, providing the black imaging background necessary for optimal detection of a NIR fluorophore within the surgical field
  • Additionally, optical imaging techniques, such as NIR fluorescence, eliminate the need for ionizing radiation. This, combined with the availability of a NIR fluorophore already FDA-approved for other indications and having extremely low toxicity (discussed below), make this a potentially safe imaging modality.

The main disadvantage is that it’s invisible to the human eye, requiring special imaging-systems to “see” the NIR fluorescence.

Currently there are three intraoperative NIR imaging systems in various stages of development:

  • The SPY system (Novadaq, Canada) – utilizes laser light excitation in order to obtain fluorescent images. The Spy system has been studied for imaging patency of vascular anastamoses following CABG and organ transplantation
  • The Photodynamic Eye(Hamamatsu, Japan) – is presently available only in Japan
  • The Fluorescence-Assisted Resection and Exploration (FLARE) system ()- developed by the authors’ laboratory utilizes NIR light-emitting diode (LED) excitation, eliminating the need for a potentially harmful laser. Additionally, the FLAREsystem has the advantage of being able to provide simultaneous color imaging, NIR fluorescence imaging, and color-NIR merged images, allowing the surgeon to simultaneously visualize invisible NIR fluorescence images within the context of surgical anatomy.

Near-Infrared Fluorescent Nanoparticle Contrast Agents

The ideal contrast agent for SLN mapping would be anionic and within 10–50 nm in size in order to facilitate rapid uptake into lymphatic vessels with optimal retention within the SLN.

Due to the lack of endogenous NIR tissue fluorescence, exogenous contrast agents must be administered for in vivo studies. The most important contrast agents that emit within the NIR spectrum are the heptamethine cyanines fluorophores, of which indocyanine green (ICG) is the most widely used, and fluorescent semiconductor nanocrystals, also known as quantum dots (QDs).

  • ICG is an extremely safe NIR fluorophore, with its only known toxicity being rare anaphylaxis. The dye was FDA approved in 1958 for systemic administration for indicator-dilution studies including measurements of cardiac output and hepatic function. Additionally, it is commonly used in ophthalmic angiography. When given intravenously, ICG is rapidly bound to plasma albumin and cleared from the blood via the biliary system. Peak absorption and emission of ICG occur at 780 nm and 830 nm respectively, within the window where in vivo tissue absorption is at its minimum. ICG has a relatively neutral charge, has a hydrodynamic diameter of only 1.2 nm, and is relatively hydrophobic. Unfortunately, this results in rapid transport out of the SLN and relatively low fluorescence yield, thereby decreasing its efficacy in mapping techniques. However, noncovalent adsorption of ICG to human serum albumin (HSA), as occurs within plasma, results in an anionic nanoparticle with a diameter of 7.3 nm and a three-fold increase in fluorescence yield markedly improving its utility in SLN mapping.
  • QDs consist of an inorganic heavy metal core and shell which emit within the NIR spectrum. This structure is then surrounded by a hydrophilic organic coating which facilitates aqeuous solubility and lymphatic distrubtion. QDs have been extensively studied and are ideal for SLN mapping as their hydrodynamic diameter can be customized to the appropriate size within a narrow distribution (15–20 nm), they can be engineered to have an anionic surface charge, and exhibit an extremely high SBRs with significant photostability. Unfortunately, safety concerns due to the presence of heavy metals within the QDs so far have precluded clinical application

Human Clinical Trials and NIR SLN mapping

Several studies have investigated the clinical use of indocyanine green without adsorption to HSA for NIR fluorescence-guided SLN mapping in breast and gastric cancer with good success (9-13).

Kitai et al. first examined this technique in 2005 in breast cancer patients, and was able to identify a SLN node in 17 of 18 patients using NIR fluorescence rather than the visible green color of ICG (9). Sevick-Muraca et al. reported similar results using significantly lower microdoses of ICG (10 – 100 μg), successfully identifying the SLN in 8 of 9 patients (11). Similar to these subcutaneous studies, 56 patients with gastric cancer underwent endoscopic ICG injection into the submucosa around the tumor 1 to 3 days preoperatively or injection directly into the subserosa intraoperatively with identification of the SLN in 54 patients (13).

Recently, Troyan et al. have completed a pilot phase I clinical trial examining the utility of NIR imaging the ICG:HSA nanoparticle fluorophore for SLN mapping/biopsy in breast cancer using the FLAREsystem. In this study, 6 patients received both 99mTc-sulfur colloid lymphoscintigraphy along with ICG:HSA at micromolar doses. SLNs were identified in all patients using both methods. In 4 of 6 patients the SLNs identified were the same, while in the remaining two, lymphoscintigraphy identified an additional node in one patient and ICG:HSA identified an additional SLN in the other. Irrespective, this study demonstrates that NIR SLN mapping with low dose ICG:HSA is a viable method for intraoperative SLN identification.

Nanotechnology and Drug Delivery in Lung cancer

We previously explored Lung cancer and nanotechnology aspects as polymer nanotechnology has been an area of significant research over the past decade as polymer nanoparticle drug delivery systems offer several advantages over traditional methods of chemotherapy delivery

see: (15) http://pharmaceuticalintelligence.com/2012/11/08/lung-cancer-nsclc-drug-administration-and-nanotechnology/                (16) http://pharmaceuticalintelligence.com/2012/12/01/diagnosing-lung-cancer-in-exhaled-breath-using-gold-nanoparticles/

As the importance of micrometastatic lymphatic spread of tumor becomes clearer, there has been much interest in the use of nanoparticles for lymphatic drug delivery. The considerable focus on developing an effective method for SLN mapping for lung cancer is indicative of the importance of nodal spread on overall survival.

Our lab is investigating the use of image-guided nanoparticles engineered for lymphatic drug delivery. We have previously described the synthesis of novel, pH-responsive methacrylate nanoparticle systems (14). Following a simple subcutaneous injection of NIR fluorophore-labeled nanoparticles 70 nm in size, we have shown that we can deliver paclitaxel loaded within the particles to regional draining lymph nodes in several organ systems of Yorkshire pigs while simultaneously confirming nodal migration using NIR fluorescent light. Future studies will need to investigate the ability of nanoparticles to treat and prevent nodal metastases in animal cancer models. Additionally, the development of tumor specific nanoparticles will potentially allow for targeting of chemotherapy to small groups of metastatic tumor cells further limiting systemic toxicities by narrowing the delivery of cytotoxic drugs.

Ref:

1. http://www.nature.com.rproxy.tau.ac.il/nrc/journal/v12/n1/pdf/nrc3180.pdf

2. http://www.nature.com/nrc/focus/metastasis/index.html

3. http://www.cancer.gov/cancertopics/factsheet/Sites-Types/metastatic

4. http://www.cancerresearchuk.org/cancer-help/about-cancer/what-is-cancer/body/the-lymphatic-system

5. http://www.macmillan.org.uk/Cancerinformation/Cancertypes/Lymphnodessecondary/Secondarycancerlymphnodes.aspx

6. Khullar O, Frangioni JV and Colson YL. Image-Guided Sentinel Lymph Node Mapping and Nanotechnology-Based Nodal Treatment in Lung Cancer using Invisible Near-Infrared Fluorescent Light. Semi Thorac Cardiovasc Surg 2009 :21 (4);  309-315. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3109504/

7. Stacker SA, Achen MG, Jussila L,  Baldwin ME and Alitalo K. Metastasis: Lymphangiogenesis and cancer metastasis.  Nature Reviews Cancer 2002 2, 573-583. http://www.nature.com/nrc/journal/v2/n8/full/nrc863.html

8. Schroeder A., Heller DA., Winslow MM., Dahlman JE., Pratt GW., Langer R., Jacks T and Anderson DG.. Nature Reviews Cancer 2012; 12(1), 39-50. Treating metastatic cancer with nanotechnology. http://www.nature.com.rproxy.tau.ac.il/nrc/journal/v12/n1/pdf/nrc3180.pdf

http://www.nature.com.rproxy.tau.ac.il/nrc/journal/v12/n1/full/nrc3180.html

9. Kitai T, Inomoto T, Miwa M, et al. Fluorescence navigation with indocyanine green for detecting sentinel lymph nodes in breast cancer. Breast Cancer. 2005;12:211–215.

10. Ogasawara Y, Ikeda H, Takahashi M, et al. Evaluation of breast lymphatic pathways with indocyanine green fluorescence imaging in patients with breast cancer. World journal of surgery.2008;32:1924–1929.

11. Sevick-Muraca EM, Sharma R, Rasmussen JC, et al. Imaging of lymph flow in breast cancer patients after microdose administration of a near-infrared fluorophore: feasibility study. Radiology.2008;246:734–741.

12. Miyashiro I, Miyoshi N, Hiratsuka M, et al. Detection of sentinel node in gastric cancer surgery by indocyanine green fluorescence imaging: comparison with infrared imaging. Ann Surg Oncol.2008;15:1640–1643.

13. Tajima Y, Yamazaki K, Masuda Y, et al. Sentinel node mapping guided by indocyanine green fluorescence imaging in gastric cancer. Ann Surg. 2009;249:58–62.

14. Griset AP, Walpole J, Liu R, et al. Expansile nanoparticles: synthesis, characterization, and in vivo efficacy of an acid-responsive drug delivery system. J Am Chem Soc. 2009;131:2469–2471

15. http://pharmaceuticalintelligence.com/2012/11/08/lung-cancer-nsclc-drug-administration-and-nanotechnology/

16.  http://pharmaceuticalintelligence.com/2012/12/01/diagnosing-lung-cancer-in-exhaled-breath-using-gold-nanoparticles/

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Identification of Biomarkers that are Related to the Actin Cytoskeleton

Curator and Writer: Larry H Bernstein, MD, FCAP

Article I Identification of Biomarkers that are Related to the Actin Cytoskeleton

This is Part I in a series of articles on Calcium and Cell motility.

The Series consists of the following articles:

Part I: Identification of Biomarkers that are Related to the Actin Cytoskeleton

Larry H Bernstein, MD, FCAP

http://pharmaceuticalintelligence.com/2012/12/10/identification-of-biomarkers-that-are-related-to-the-actin-cytoskeleton/

Part II: Role of Calcium, the Actin Skeleton, and Lipid Structures in Signaling and Cell Motility

Larry H. Bernstein, MD, FCAP, Stephen Williams, PhD and Aviva Lev-Ari, PhD, RN

http://pharmaceuticalintelligence.com/2013/08/26/role-of-calcium-the-actin-skeleton-and-lipid-structures-in-signaling-and-cell-motility/

Part III: Renal Distal Tubular Ca2+ Exchange Mechanism in Health and Disease

Larry H. Bernstein, MD, FCAP, Stephen J. Williams, PhD
 and Aviva Lev-Ari, PhD, RN

http://pharmaceuticalintelligence.com/2013/09/02/renal-distal-tubular-ca2-exchange-mechanism-in-health-and-disease/

Part IV: The Centrality of Ca(2+) Signaling and Cytoskeleton Involving Calmodulin Kinases and Ryanodine Receptors in Cardiac Failure, Arterial Smooth Muscle, Post-ischemic Arrhythmia, Similarities and Differences, and Pharmaceutical Targets

Larry H Bernstein, MD, FCAP, Justin Pearlman, MD, PhD, FACC and Aviva Lev-Ari, PhD, RN

http://pharmaceuticalintelligence.com/2013/09/08/the-centrality-of-ca2-signaling-and-cytoskeleton-involving-calmodulin-kinases-and-ryanodine-receptors-in-cardiac-failure-arterial-smooth-muscle-post-ischemic-arrhythmia-similarities-and-differen/

Part V: Ca2+-Stimulated Exocytosis:  The Role of Calmodulin and Protein Kinase C in Ca2+ Regulation of Hormone and Neurotransmitter

Larry H Bernstein, MD, FCAP
and
Aviva Lev-Ari, PhD, RN

http://pharmaceuticalintelligence.com/2013/12/23/calmodulin-and-protein-kinase-c-drive-the-ca2-regulation-of-hormone-and-neurotransmitter-release-that-triggers-ca2-stimulated-exocytosis/

Part VI: Calcium Cycling (ATPase Pump) in Cardiac Gene Therapy: Inhalable Gene Therapy for Pulmonary Arterial Hypertension and Percutaneous Intra-coronary Artery Infusion for Heart Failure: Contributions by Roger J. Hajjar, MD

Aviva Lev-Ari, PhD, RN

http://pharmaceuticalintelligence.com/2013/08/01/calcium-molecule-in-cardiac-gene-therapy-inhalable-gene-therapy-for-pulmonary-arterial-hypertension-and-percutaneous-intra-coronary-artery-infusion-for-heart-failure-contributions-by-roger-j-hajjar/

Part VII: Cardiac Contractility & Myocardium Performance: Ventricular Arrhythmias and Non-ischemic Heart Failure – Therapeutic Implications for Cardiomyocyte Ryanopathy (Calcium Release-related Contractile Dysfunction) and Catecholamine Responses

Justin Pearlman, MD, PhD, FACC, Larry H Bernstein, MD, FCAP and Aviva Lev-Ari, PhD, RN

http://pharmaceuticalintelligence.com/2013/08/28/cardiac-contractility-myocardium-performance-ventricular-arrhythmias-and-non-ischemic-heart-failure-therapeutic-implications-for-cardiomyocyte-ryanopathy-calcium-release-related-contractile/

Part VIII: Disruption of Calcium Homeostasis: Cardiomyocytes and Vascular Smooth Muscle Cells: The Cardiac and Cardiovascular Calcium Signaling Mechanism

Justin Pearlman, MD, PhD, FACC, Larry H Bernstein, MD, FCAP and Aviva Lev-Ari, PhD, RN

http://pharmaceuticalintelligence.com/2013/09/12/disruption-of-calcium-homeostasis-cardiomyocytes-and-vascular-smooth-muscle-cells-the-cardiac-and-cardiovascular-calcium-signaling-mechanism/

Part IXCalcium-Channel Blockers, Calcium Release-related Contractile Dysfunction (Ryanopathy) and Calcium as Neurotransmitter Sensor

Justin Pearlman, MD, PhD, FACC, Larry H Bernstein, MD, FCAP and Aviva Lev-Ari, PhD, RN

Part X: Synaptotagmin functions as a Calcium Sensor: How Calcium Ions Regulate the fusion of vesicles with cell membranes during Neurotransmission

Larry H Bernstein, MD, FCAP and Aviva Lev-Ari, PhD, RN

http://pharmaceuticalintelligence.com/2013/09/10/synaptotagmin-functions-as-a-calcium-sensor-how-calcium-ions-regulate-the-fusion-of-vesicles-with-cell-membranes-during-neurotransmission/

Part XI: Sensors and Signaling in Oxidative Stress

Larry H. Bernstein, MD, FCAP

http://pharmaceuticalintelligence.com/2013/11/01/sensors-and-signaling-in-oxidative-stress/

Part XII: Atherosclerosis Independence: Genetic Polymorphisms of Ion Channels Role in the Pathogenesis of Coronary Microvascular Dysfunction and Myocardial Ischemia (Coronary Artery Disease (CAD))

Larry H Bernstein, MD, FCAP and Aviva Lev-Ari, PhD, RN

http://pharmaceuticalintelligence.com/2013/12/21/genetic-polymorphisms-of-ion-channels-have-a-role-in-the-pathogenesis-of-coronary-microvascular-dysfunction-and-ischemic-heart-disease/

In this article the Author will cover two types of biomarker on the function of actin in cytoskeleton mobility in situ.

  • First, is an application in developing the actin or other component, for a biotarget and then, to be able to follow it as

(a) a biomarker either for diagnosis, or

(b) for the potential treatment prediction of disease free survival.

  • Second, is mostly in the context of MI, for which there is an abundance of work to reference, and a substantial body of knowledge about

(a) treatment and long term effects of diet, exercise, and

(b) underlying effects of therapeutic drugs.

1.  Cell Membrane (cytoskeletal) Plasticity

Refer to … Squeezing Ovarian Cancer Cells to Predict Metastatic Potential: Cell Stiffness as Possible Biomarker

Reporter/curator: Prabodh Kandala, PhD

New Georgia Tech research shows that cell stiffness could be a valuable clue for doctors as they search for and treat cancerous cells before they’re able to spread. The findings, which are published in the journal PLoS One, found that highly metastatic ovarian cancer cells are several times softer than less metastatic ovarian cancer cells. This study used atomic force microscopy (AFM) to study the mechanical properties of various ovarian cell lines. A soft mechanical probe “tapped” healthy, malignant and metastatic ovarian cells to measure their stiffness. In order to spread, metastatic cells must push themselves into the bloodstream. As a result, they must be highly deformable and softer. This study results indicate that cell stiffness may be a useful biomarker to evaluate the relative metastatic potential of ovarian and perhaps other types of cancer cells.

Comparative gene expression analyses indicate that the reduced stiffness of highly metastatic HEY A8 cells is associated with actin cytoskeleton remodeling and microscopic examination of actin fiber structure in these cell lines is consistent with this prediction.   The results suggest either of two approaches. Atomic Force Microscopy is not normally used by pathologists in diagnostics. Electron microscopy requires space for making and cutting the embedded specimen, and a separate room for the instrument. The instrument is large and the technique was not suitable for anything other than research initially until EM gained importance in Renal Pathology. It has not otherwise been used.  This new method looks like it might be more justified over a spectrum of cases.

A.  Atomic Force Microscopy

So the first point related to microscopy is whether AFM has feasibility for routine clinical use in the pathologists’ hands. This requires:

  1. suitable size of equipment
  2.  suitable manipulation of the specimen
  3. The question of whether you are using overnight fixed specimen, or whether the material is used unfixed
  4. Nothing is said about staining of cells for identification.
  5. Then there is the question about whether this will increase the number of Pathologist Assistants used across the country, which I am not against.   This would be the end of “house” trained PAs, and gives more credence to the too few PA programs across the country. The PA programs have to be reviewed and accredited by NAACLS (I served 8 years on the Board). A PA is represented on the Board, and programs are inspected by qualified peers.   There is no academic recognition given to this for tenure and promotion in Pathology Departments, and a pathologist is selected for a medical advisory role by the ASCP, and must be a Medical Advisor to a MLS accredited Program.   The fact is that PAs do gross anatomic dictation of selected specimens, and they do autopsies under the guidance of a pathologist. This is the reality of the profession today. The pathologist has to be in attendance at a variety of quality review conferences, for surgical morbidity and mortality to obstetrics review, and the Cancer Review. Cytopathology and cytogenetics are in the pathology domain.   In the case of tumors of the throat, cervix, and accessible orifices, it seems plausible to receive a swab for preparation. However, sampling error is greater than for a biopsy. A directed needle biopsy or a MIS specimen is needed for the ovary.

B.  identification of biomarkers that are related to the actin cytoskeleton

The alternative to the first approach is the identification of biomarkers that are related to the actin cytoskeleton, perhaps in the nature of the lipid or apoprotein isoform that gives the cell membrane deformability. The method measuring by Atomic Force Microscopy is shown with the current method of cytological screening, and I call attention to cells clustered together that have a scant cytoplasm surrounding nuclei occupying 1/2 to 3/4 of the cell radius.  The cells are not anaplastic, but the clumps are suggestive of glnad forming epithelium.

English: Animation showing 3-D nature of clust...

English: Animation showing 3-D nature of cluster. Image:Serous carcinoma 2a – cytology.jpg (Photo credit: Wikipedia)

The cell membrane, also called the plasma memb...

The cell membrane, also called the plasma membrane or plasmalemma, is a semipermeable lipid bilayer common to all living cells. It contains a variety of biological molecules, primarily proteins and lipids, which are involved in a vast array of cellular processes. It also serves as the attachment point for both the intracellular cytoskeleton and, if present, the cell wall. (Photo credit: Wikipedia)

English: AFM bema detection

AFM non contact mode

AFM non contact mode (Photo credit: Wikipedia)

C.  The diagnosis of ovarian cancer can be problematic because it can have a long period of growth undetected.

On the other hand, it is easily accessible once there is reason to suspect it. They are terrible to deal with because they metastasize along the abdominal peritoneum and form a solid cake. It is a problem of location and silence until it is late. Once they do announce a presence on the abdominal wall, there is probably a serous effusion. It was not possible to rely on a single marker, but when CA125 was introduced, Dr. Marguerite Pinto, Chief of Cytology at Bridgeport Hospital-Yale New Haven Health came to the immnunochemistry lab and we worked out a method for analyzing effusions, as we had already done with carcinoembryonic antigen.       The use of CEA and CA125 was published by Pinto and Bernstein as a first that had an impact.  This was followed by a study with the Chief of Oncology, Dr. Martin Rosman, that showed that the 30 month survival of patients post treatment is predicted by the half-life of disappearance of CA125 in serum.  At the time of this writing, I am not sure of the extent of its use 20 years later. History has taught us that adoption can be slow, depending very much on dissemination from major academic medical centers.  On the other hand, concepts can also be stuck at academic medical centers because of a rigid and unprepared mindset in the professional community.  The best example of this is the story of Ignaz Semmelweis, the best student of Rokitansky in Vienna for discovering the cause and prevention of childbirth fever at a time that nursemaids had far better results at obstetrical delivery than physicians.  Contrary to this, Edward Jenner, the best student of John Hunter (anatomist, surgeon, and physician to James Hume), discovered vaccination from the observation that milkmaids did not get smallpox (cowpox was a better alternative).
Only this year a Nobel Prize in Physics was awarded to an Israeli scientist who, working in the US, was unable to convince his associates of his discovery of PSEUDOCRYSTALS. – Diagnostic efficiency of carcinoembryonic antigen and CA125 in the cytological evaluation of effusions. M M Pinto, L H Bernstein, R A Rudolph, D A Brogan, M Rosman Arch Pathol Lab Med 1992; 116(6):626-631 ICID: 825503 Article type: Review article – Immunoradiometric assay of CA 125 in effusions. Comparison with carcinoembryonic antigen. M M Pinto, L H Bernstein, D A Brogan, E Criscuolo Cancer 1987; 59(2):218-222 ICID: 825555 Article type: Review article – Carcinoembryonic antigen in effusions. A diagnostic adjunct to cytology. M M Pinto, L H Bernstein, D A Brogan, E M Criscuolo Acta Cytologica 1987; 31(2):113-118 ICID: 825557

Predictive Modeling

Ovarian Cancer a plot of the CA125 elimination half-life vs the Kullback-Liebler distance

Ca125 half-life vs Kullback Entropy                                                          HL vs Survival KM plot 

Troponin(s) T, I, C  and the contractile apparatus  (contributed by Aviva Lev-Ari, PhD, RN)

 

For 2012 – 2013 Frontier Contribution in Cardiology on Gene Therapy Solutions for Improving Myocardial Contractility, see

Lev-Ari, A. 8/1/2013 Calcium Cycling (ATPase Pump) in Cardiac Gene Therapy: Inhalable Gene Therapy for Pulmonary Arterial Hypertension and Percutaneous Intra-coronary Artery Infusion for Heart Failure: Contributions by Roger J. Hajjar, MD

http://pharmaceuticalintelligence.com/2013/08/01/calcium-molecule-in-cardiac-gene-therapy-inhalable-gene-therapy-for-pulmonary-arterial-hypertension-and-percutaneous-intra-coronary-artery-infusion-for-heart-failure-contributions-by-roger-j-hajjar/

For explanation of Conduction prior to Myocardial Contractility, see

Lev-Ari, A. 4/28/2013 Genetics of Conduction Disease: Atrioventricular (AV) Conduction Disease (block): Gene Mutations – Transcription, Excitability, and Energy Homeostasis

http://pharmaceuticalintelligence.com/2013/04/28/genetics-of-conduction-disease-atrioventricular-av-conduction-disease-block-gene-mutations-transcription-excitability-and-energy-homeostasis/

The contraction of skeletal muscle is triggered by nerve impulses, which stimulate the release of Ca2+ from the sarcoplasmic reticulum—a specialized network of internal membranes, similar to the endoplasmic reticulum, that stores high concentrations of Ca2+ ions. The release of Ca2+ from the sarcoplasmic reticulum increases the concentration of Ca2+ in the cytosol from approximately 10-7 to 10-5 M. The increased Ca2+ concentration signals muscle contraction via the action of two accessory proteins bound to the actin filaments: tropomyosin and troponin (Figure 11.25). Tropomyosin is a fibrous protein that binds lengthwise along the groove of actin filaments. In striated muscle, each tropomyosin molecule is bound to troponin, which is a complex of three polypeptides: troponin C (Ca2+-binding), troponin I (inhibitory), and troponin T (tropomyosin-binding).

  • When the concentration of Ca2+ is low, the complex of the troponins with tropomyosin blocks the interaction of actin and myosin, so the muscle does not contract.
  • At high concentrations, Ca2+ binding to troponin C shifts the position of the complex, relieving this inhibition and allowing contraction to proceed.

Figure 11.25

Association of tropomyosin and troponins with actin filaments. (A) Tropomyosin binds lengthwise along actin filaments and, in striated muscle, is associated with a complex of three troponins: troponin I (TnI), troponin C (TnC), and troponin T (TnT). In (more…)
Contractile Assemblies of Actin and Myosin in Nonmuscle Cells

Contractile assemblies of actin and myosin, resembling small-scale versions of muscle fibers, are present also in nonmuscle cells. As in muscle, the actin filaments in these contractile assemblies are interdigitated with bipolar filaments of myosin II, consisting of 15 to 20 myosin II molecules, which produce contraction by sliding the actin filaments relative to one another (Figure 11.26). The actin filaments in contractile bundles in nonmuscle cells are also associated with tropomyosin, which facilitates their interaction with myosin II, probably by competing with filamin for binding sites on actin.

Figure 11.26

Contractile assemblies in nonmuscle cells. Bipolar filaments of myosin II produce contraction by sliding actin filaments in opposite directions.

Two examples of contractile assemblies in nonmuscle cells, stress fibers and adhesion belts, were discussed earlier with respect to attachment of the actin cytoskeleton to regions of cell-substrate and cell-cell contacts (see Figures 11.13 and 11.14). The contraction of stress fibers produces tension across the cell, allowing the cell to pull on a substrate (e.g., the extracellular matrix) to which it is anchored. The contraction of adhesion belts alters the shape of epithelial cell sheets: a process that is particularly important during embryonic development, when sheets of epithelial cells fold into structures such as tubes.

The most dramatic example of actin-myosin contraction in nonmuscle cells, however, is provided by cytokinesis—the division of a cell into two following mitosis (Figure 11.27). Toward the end of mitosis in animal cells, a contractile ring consisting of actin filaments and myosin II assembles just underneath the plasma membrane. Its contraction pulls the plasma membrane progressively inward, constricting the center of the cell and pinching it in two. Interestingly, the thickness of the contractile ring remains constant as it contracts, implying that actin filaments disassemble as contraction proceeds. The ring then disperses completely following cell division.

Figure 11.27

Cytokinesis. Following completion of mitosis (nuclear division), a contractile ring consisting of actin filaments and myosin II divides the cell in two.

http://www.ncbi.nlm.nih.gov/books/NBK9961/

2.  Use of Troponin(s) in Diagnosis

Troponins T and I are released into the circulation at the time of an acute coronary syndrome (ACS).  Troponin T was first introduced by Roche (developed in Germany) for the Roche platform as a superior biomarker for identifying acute myocardial infarction (AMI), because of a monoclonal specificity to the cardiac troponin T.  It could not be measured on any other platform (limited license patent), so the Washington University Clinical Chemistry group developed a myocardiocyte specific troponin I that quickly became widely available to Beckman, and was adapted to other instruments.  This was intended to replace the CK isoenzyme MB, that is highly elevated in rhabdomyolysis associated with sepsis or with anesthesia in special cases.

The troponins I and T had a tenfold scale difference, and the Receiver Operator Curve Generated cutoff was accurate for AMI, but had significant elevation with end-stage renal disease.  The industry worked in concert to develop a high sensitivity assay for each because there were some missed AMIs just below the ROC cutoff, which could be interpreted as Plaque Rupture.  However, the concept of plaque rupture had to be reconsidered, and we are left with type1 and type 2 AMI (disregarding the case of post PCI or CABG related).   This led to the current establishment of 3 standard deviations above the lowest measureable level at 10% coefficient of variation.  This has been discussed sufficiently elsewhere.  It did introduce a problem in the use of the test as a “silver bullet” once the finer distinctions aqnd the interest in using the test for prognosis as well as diagnosis.   This is where the use of another protein associated with heart failure came into play – either the B type natriuretic peptide, or its propeptide, N-terminal pro BNP.  The prognostic value of using these markers, secreted by the HEART and acting on the kidneys (sodium reabsorption) has proved useful.  But there has not been a multivariate refinement of the use of a two biomarker approach.  In the following part D, I illustrate what can be done with an algorithmic approach to multiple markers.

Software Agent for Diagnosis of AMI

Isaac E. Mayzlin, Ph.D., David Mayzlin, Larry H. Bernstein, M.D. The so called gold standard of proof of a method is considered the Receiver-Operating Characteristic Curve, developed for detecting “enemy planes or missiles”, and adopted first by radiologists in medicine.  This matches the correct “hits” to the actual calssification and it is generally taught as a plot of sensitivity vs (1 – specifity).  But what if you had no “training” variable?  Work inspired by Eugene Rypka’s bacterial classification led to Rosser Rudolph’s application of the Entropy of Shannon and Weaver to identify meaningful information, referring to what was Kullback-Liebler distance as “effective information”.  This allowed Rudolph and Bernstein to classify using disease biomarkers obtaing the same results as the ROC curve using an apl program.  The same data set was used by Bernstein, Adan et al. previously, and was again used by Izaak Mayzlin from University of Moscow with a new wrinkle.  Dr. Mayzlin created a neural network (Maynet), and then did a traditional NN with training on the data, and also clustered the data using geometric distance clustering and trained on the clusters.  It was interesting to see that the optimum cluster separation was closely related to the number of classes and the accuracy of classification.  An earlier simpler model using the slope of the MB isoenzyme increase and percent of total CK activity was perhaps related to Burton Sobel’s work on CK-MB disappearance rate for infarct size. The main process consists of three successive steps: (1)       clustering performed on training data set, (2)       neural network’s training on clusters from previous step, and (3)       classifier’s accuracy evaluation on testing data. The classifier in this research will be the ANN, created on step 2, with output in the range [0,1], that provides binary result (1 – AMI, 0 – not AMI), using decision point 0.5. Table  1.  Effect  of  selection  of  maximum  distance  on  the  number  of  classes  formed  and  on  the accuracy of recognition by ANN

Clustering Distance Factor F(D = F * R) Number ofClasses Number of Nodes in The Hidden Layers Number of Misrecognized Patterns inThe TestingSet of 43 Percent ofMisrecognized
10.90.80.7 2414135 1,  02,  03,  01,  02,  03,  0 3,  2 3,  2 121121 1 1 2.34.62.32.34.62.3 2.3 2.3

Creatine kinase B-subunit activity in serum in cases of suspected myocardial infarction: a prediction model based on the slope of MB increase and percentage CK-MB activity. L H Bernstein, G Reynoso Clin Chem 1983; 29(3):590-592 ICID: 825549 Diagnosis of acute myocardial infarction from two measurements of creatine kinase isoenzyme MB with use of nonparametric probability estimation. L H Bernstein, I J Good, G I Holtzman, M L Deaton, J Babb.  Clin Chem 1989; 35(3):444-447 ICID: 825570 – Information induction for predicting acute myocardial infarction. R A Rudolph, L H Bernstein, J Babb. Clin Chem 1988; 34(10):2031-2038 ICID: 825568

Related articles

Related articles published on this Open Access Online Scientific Journal, include the following:

Calcium Cycling (ATPase Pump) in Cardiac Gene Therapy: Inhalable Gene Therapy for Pulmonary Arterial Hypertension and Percutaneous Intra-coronary Artery Infusion for Heart Failure: Contributions by Roger J. Hajjar, MD

Aviva Lev-Ari, PhD, RN 8/1/2013

http://pharmaceuticalintelligence.com/2013/08/01/calcium-molecule-in-cardiac-gene-therapy-inhalable-gene-therapy-for-pulmonary-arterial-hypertension-and-percutaneous-intra-coronary-artery-infusion-for-heart-failure-contributions-by-roger-j-hajjar/

High-Sensitivity Cardiac Troponin Assays- Preparing the United States for High-Sensitivity Cardiac Troponin Assays

Larry Bernstein, MD, FCAP 6/13/2013

http://pharmaceuticalintelligence.com/2013/06/13/high-sensitivity-cardiac-troponin-assays/

Dealing with the Use of the High Sensitivity Troponin (hs cTn) Assays

Larry Bernstein and Aviva Lev-Ari  5/18/2013

http://pharmaceuticalintelligence.com/2013/05/18/dealing-with-the-use-of-the-hs-ctn-assays/

Acute Chest Pain/ER Admission: Three Emerging Alternatives to Angiography and PCI – Corus CAD, hs cTn, CCTA

Aviva Lev-Ari  3/10/2013

http://pharmaceuticalintelligence.com/2013/03/10/acute-chest-painer-admission-three-emerging-alternatives-to-angiography-and-pci/

  • Redberg’s conclusions are correct for the initial screening. The issue has been whether to do further testing for low or intermediate risk patients.
  • The most intriguing finding that is not at all surprising is that the CCTA added very little in the suspect group with small or moderate risk.
  • The ultra sensitive troponin threw the ROC out the window
  • The improved assay does pick up minor elevations of troponin in the absence of MI.

Critical Care | Abstract | Cardiac ischemia in patients with septic …
Aviva Lev-Ari  6/26/2013
http://pharmaceuticalintelligence.com/2013/06/26/critical-care-abstract-cardiac-ischemia-in-patients-with-septic/

  • refer to:  Cardiac ischemia in patients with septic shock randomized to vasopressin or norepinephrine

Mehta S, Granton J,  Gordon AC, Cook DJ, et al.
Critical Care 2013, 17:R117   http://dx.doi.org/10.1186/cc12789
Troponin and CK levels, and rates of ischemic ECG changes were similar in the VP and NE groups. In multivariable analysis

  • only APACHE II was associated with 28-day mortality (OR 1.07, 95% CI 1.01-1.14, p=0.033).

Assessing Cardiovascular Disease with Biomarkers

Larry H Bernstein, MD, FCAP 12/25/2012

http://pharmaceuticalintelligence.com/2012/12/25/assessing-cardiovascular-disease-with-biomarkers/

Vascular Medicine and Biology: CLASSIFICATION OF FAST ACTING THERAPY FOR PATIENTS AT HIGH RISK FOR MACROVASCULAR EVENTS Macrovascular Disease – Therapeutic Potential of cEPCs

Aviva Lev-Ari, PhD, RN 8/24/2012

http://pharmaceuticalintelligence.com/2012/08/24/vascular-medicine-and-biology-classification-of-fast-acting-therapy-for-patients-at-high-risk-for-macrovascular-events-macrovascular-disease-therapeutic-potential-of-cepcs/

 PENDING Integration

  • ‘Ryanopathy’: causes and manifestations of RyR2 dysfunction in heart failureCardiovasc Res. 2013;98:240-247,
  • Up-regulation of sarcoplasmic reticulum Ca2+ uptake leads to cardiac hypertrophy, contractile dysfunction and early mortality in mice deficient in CASQ2Cardiovasc Res. 2013;98:297-306,
  • Myocardial Delivery of Stromal Cell-Derived Factor 1 in Patients With Ischemic Heart Disease: Safe and PromisingCirc. Res.. 2013;112:746-747,
  • Circulation Research Thematic Synopsis: Cardiovascular GeneticsCirc. Res.. 2013;112:e34-e50,
  • Gene and cytokine therapy for heart failure: molecular mechanisms in the improvement of cardiac functionAm. J. Physiol. Heart Circ. Physiol.. 2012;303:H501-H512,
  • Ryanodine Receptor Phosphorylation and Heart Failure: Phasing Out S2808 and “Criminalizing” S2814Circ. Res.. 2012;110:1398-1402,

http://circres.ahajournals.org/content/110/5/777.figures-only

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Screen Shot 2021-07-19 at 7.15.40 PM

Word Cloud By Danielle Smolyar

Reporter/curator: Prabodh Kandala, PhD

New Georgia Tech research shows that cell stiffness could be a valuable clue for doctors as they search for and treat cancerous cells before they’re able to spread. The findings, which are published in the journal PLoS One, found that highly metastatic ovarian cancer cells are several times softer than less metastatic ovarian cancer cells.

This study used atomic force microscopy (AFM) to study the mechanical properties of various ovarian cell lines. A soft mechanical probe “tapped” healthy, malignant and metastatic ovarian cells to measure their stiffness. In order to spread, metastatic cells must push themselves into the bloodstream. As a result, they must be highly deformable and softer. This study results indicate that cell stiffness may be a useful biomarker to evaluate the relative metastatic potential of ovarian and perhaps other types of cancer cells.

ust as previous studies on other types of epithelial cancers have indicated, Sulchek also found that cancerous ovarian cells are generally softer and display lower intrinsic variability in cell stiffnesss than non-malignant cells.

Sulchek’s lab partnered with the molecular cancer lab of Biology Professor John McDonald, who is also director of Georgia Tech’s newly established Integrated Cancer Research Center.

“This is a good example of the kinds of discoveries that only come about by integrating skills and knowledge from traditionally diverse fields such as molecular biology and bioengineering,” said McDonald. “Although there are a number of developing methodologies to identify circulating cancer cells in the blood and other body fluids, this technology offers the added potential to rapidly determine if these cells are highly metastatic or relatively benign.”

Sulchek and McDonald believe that, when further developed, this technology could offer a huge advantage to clinicians in the design of optimal chemotherapies, not only for ovarian cancer patients but also for patients of other types of cancer.

Abstract of the study:

The metastatic potential of cells is an important parameter in the design of optimal strategies for the personalized treatment of cancer. Using atomic force microscopy (AFM), we show, consistent with previous studies conducted in other types of epithelial cancer, that ovarian cancer cells are generally softer and display lower intrinsic variability in cell stiffness than non-malignant ovarian epithelial cells. A detailed examination of highly invasive ovarian cancer cells (HEY A8) relative to their less invasive parental cells (HEY), demonstrates that deformability is also an accurate biomarker of metastatic potential. Comparative gene expression analyses indicate that the reduced stiffness of highly metastatic HEY A8 cells is associated with actin cytoskeleton remodeling and microscopic examination of actin fiber structure in these cell lines is consistent with this prediction. Our results indicate that cell stiffness may be a useful biomarker to evaluate the relative metastatic potential of ovarian and perhaps other types of cancer cells.

Ref:

1. Georgia Institute of Technology (2012, October 10). Squeezing ovarian cancer cells to predict metastatic potential: Cell stiffness as possible biomarker. ScienceDaily. Retrieved December 8, 2012, from http://www.sciencedaily.com­/releases/2012/10/121010131556.htm

2. http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0046609

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Histone Deacetylase Inhibitors Induce Epithelial-to-Mesenchymal Transition in Prostate Cancer Cells(1)

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Word Cloud By Danielle Smolyar

Authors: Dejuan Kong, Aamir Ahmad, Bin Bao, Yiwei Li, Sanjeev Banarjee, Fazlul H. Sarkar, Wayne State University School of Medicine

Reporter-Curator: Stephen J. Williams, Ph.D.

Clinically, there has not been much success in treating solid tumors with histone deacetylase inhibitors (HDACi). Histone acetylation and deacetylation play an important role in transcriptional regulation of genes and increased activity is associated with many cancers, therefore it was thought that HDAC inhibition might be fruitful as a therapy.  There have been several phase I and II clinical trials using HDACi for treatment of various malignancies, including hematological and solid malignancies(2), with most success seen in hematologic malignancies such as cutaneous T-cell lymphoma and peripheral T-cell lymphoma and little or no positive outcome with solid tumors.  Many mechanisms of resistance to HDACi in solid tumors have been described, most of which are seen with other chemotherapeutics such as increased multidrug resistance gene MDR1, increased anti-apoptotic proteins and activation of cell survival pathways(3).

A report in PLOS One by Dr. Dejuan Kong, Dr. Fazlul Sarkar, and colleagues from Wayne State University School of Medicine, demonstrate another possible mechanism of resistance to HDACi in prostate cancer, by induction of the epithelial-to-mesenchymal transition (EMT), which has been associated with the development of resistance to chemotherapies in other malignancies of epithelial origin(4,5).

EMT is an important differentiation process in embryogenesis and felt to be important in progression of cancer.  Epithelial cells will acquire a mesenchymal morphology (on plastic this looks like a cuboidal epithelial cell gaining a more flattened, elongated, tri-corner morphology; see paper Figure 1) and down-regulate epithelial markers such as cytokeratin, up-regulation of mesenchymal markers, increased migration and invasiveness in standard assays, and increased resistance to chemotherapeutics, and similarity to cancer stem cells(6-10).

ImageFigure 1. HDACis led to the induction of EMT phemotype. (A and B) PC3 cells treated with TSA and SAHA for 24 h at indicated doses.  The photomicrographs of PC3 cells treated with TSA and SAHA exhibited a fibroblastic-type phenotype, while cells treated with DMAO control displayed rounded epithelial cell morphology (original magnification, x 100). (C) Treated PC3 cells show increased mesenchymal markers vimentin and ZEB1 and F-actin reorganization.  Figure taken from Kong, D., Ahmad, A., Bao, B., Li, Y., Banerjee, S., and Sarkar, F. H. (2012) PloS one 7, e45045

In this study the authors found that treatment of prostate carcinoma cells with two different HDACis (trichostatin A (TSA) and suberoylanilide hydroxamic acid (SAHA)) induced EMT phenotype mediated through up-regulation of transcription factors ZEB1, ZEB2 and Slug, increased expression of mesenchymal markers vimentin, N-cadherin and fibronectin by promoting histone 3 acetylation on gene promoters.  In addition TSA increased the stem cell markers Sox2 and Nanog with concomitant EMT morphology and increased cell motility.

Below is the abstract of this paper(1):

ABSTRACT

Clinical experience of histone deacetylase inhibitors (HDACIs) in patients with solid tumors has been disappointing; however, the molecular mechanism of treatment failure is not known. Therefore, we sought to investigate the molecular mechanism of treatment failure of HDACIs in the present study. We found that HDACIs Trichostatin A (TSA) and Suberoylanilide hydroxamic acid (SAHA) could induce epithelial-to-mesenchymal transition (EMT) phenotype in prostate cancer (PCa) cells, which was associated with changes in cellular morphology consistent with increased expression of transcription factors ZEB1, ZEB2 and Slug, and mesenchymal markers such as vimentin, N-cadherin and Fibronectin. CHIP assay showed acetylation of histone 3 on proximal promoters of selected genes, which was in part responsible for increased expression of EMT markers. Moreover, TSA treatment led to further increase in the expression of Sox2 and Nanog in PCa cells with EMT phenotype, which was associated with cancer stem-like cell (CSLC) characteristics consistent with increased cell motility. Our results suggest that HDACIs alone would lead to tumor aggressiveness, and thus strategies for reverting EMT-phenotype to mesenchymal-to-epithelial transition (MET) phenotype or the reversal of CSLC characteristics prior to the use of HDACIs would be beneficial to realize the value of HDACIs for the treatment of solid tumors especially PCa.

Highlights of the research include:

  • TSA and SAHA induce morphologic changes  in prostate carcinoma LNCaP and PC3 cells related to EMT by microscopy as well as accumulation of mesenchymal markers ZEB1, vimentin, and F-actin reorganization shown by immunofluorescence microscopy and increased expression of these markers shown by real-time PCR
  • Western blotting showed TSA treatment resulted in hyperacetyulation of histone 3 whi8le CHIP analysis revealed increased histone 3 acetylation on the promoters of vimentin, ZEB2, Slug, and MMP2
  • Western analysis revealed that HDACi not only induced EMT but increased the expression of cancer stem cell markers associated with increased motility such as Sox2 and Nanog.  Increased cell migration was measured by Transwell migration assays and increased cell motility was measured via cell detachment assays

1.            Kong, D., Ahmad, A., Bao, B., Li, Y., Banerjee, S., and Sarkar, F. H. (2012) PloS one 7, e45045

2.            Bertino, E. M., and Otterson, G. A. (2011) Expert opinion on investigational drugs 20, 1151-1158

3.            Robey, R. W., Chakraborty, A. R., Basseville, A., Luchenko, V., Bahr, J., Zhan, Z., and Bates, S. E. (2011) Molecular pharmaceutics 8, 2021-2031

4.            Wang, Z., Li, Y., Kong, D., Banerjee, S., Ahmad, A., Azmi, A. S., Ali, S., Abbruzzese, J. L., Gallick, G. E., and Sarkar, F. H. (2009) Cancer research 69, 2400-2407

5.            Wang, Z., Li, Y., Ahmad, A., Azmi, A. S., Kong, D., Banerjee, S., and Sarkar, F. H. (2010) Drug resistance updates : reviews and commentaries in antimicrobial and anticancer chemotherapy 13, 109-118

6.            Hugo, H., Ackland, M. L., Blick, T., Lawrence, M. G., Clements, J. A., Williams, E. D., and Thompson, E. W. (2007) Journal of cellular physiology 213, 374-383

7.            Thiery, J. P. (2002) Nature reviews. Cancer 2, 442-454

8.            Kong, D., Banerjee, S., Ahmad, A., Li, Y., Wang, Z., Sethi, S., and Sarkar, F. H. (2010) PloS one 5, e12445

9.            Kong, D., Li, Y., Wang, Z., and Sarkar, F. H. (2011) Cancers 3, 716-729

10.          Bao, B., Wang, Z., Ali, S., Kong, D., Li, Y., Ahmad, A., Banerjee, S., Azmi, A. S., Miele, L., and Sarkar, F. H. (2011) Cancer letters 307, 26-36

Other research papers on Cancer and Cancer Therapeutics were published on this Scientific Web site as follows:

PIK3CA mutation in Colorectal Cancer may serve as a Predictive Molecular Biomarker for adjuvant Aspirin therapy

Nanotechnology Tackles Brain Cancer

Response to Multiple Cancer Drugs through Regulation of TGF-β Receptor Signaling: a MED12 Control

Personalized medicine-based cure for cancer might not be far away

GSK for Personalized Medicine using Cancer Drugs needs Alacris systems biology model to determine the in silico effect of the inhibitor in its “virtual clinical trial”

Lung Cancer (NSCLC), drug administration and nanotechnology

Non-small Cell Lung Cancer drugs – where does the Future lie?

Cancer Innovations from across the Web

arrayMap: Genomic Feature Mining of Cancer Entities of Copy Number Abnormalities (CNAs) Data

How mobile elements in “Junk” DNA promote cancer. Part 1: Transposon-mediated tumorigenesis.

Cancer Genomics – Leading the Way by Cancer Genomics Program at UC Santa Cruz

Closing the gap towards real-time, imaging-guided treatment of cancer patients.

Closing the gap towards real-time, imaging-guided treatment of cancer patients.

mRNA interference with cancer expression

Search Results for ‘cancer’ on this web site

Cancer Genomics – Leading the Way by Cancer Genomics Program at UC Santa Cruz

Closing the gap towards real-time, imaging-guided treatment of cancer patients.

Lipid Profile, Saturated Fats, Raman Spectrosopy, Cancer Cytology

mRNA interference with cancer expression

Pancreatic cancer genomes: Axon guidance pathway genes – aberrations revealed

Biomarker tool development for Early Diagnosis of Pancreatic Cancer: Van Andel Institute and Emory University

Is the Warburg Effect the cause or the effect of cancer: A 21st Century View?

Crucial role of Nitric Oxide in Cancer

Targeting Glucose Deprived Network Along with Targeted Cancer Therapy Can be a Possible Method of Treatment

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Non-small Cell Lung Cancer drugs – where does the Future lie?

In focus: Tarceva, Avastin and Dacomitinib

 

UPDATED on July 5, 2013

(from reports published in New England Journal of Medicine on drug, crizotinib)

 

Curator: Ritu Saxena, Ph.D.

 

Introduction

Non-small cell lung cancer (NSCLC) is the most common type of lung cancer and usually grows and spreads more slowly than small cell lung cancer.

There are three common forms of NSCLC:

  • Adenocarcinomas are often found in an outer area of the lung.
  • Squamous cell carcinomas are usually found in the center of the lung next to an air tube (bronchus).
  • Large cell carcinomas can occur in any part of the lung. They tend to grow and spread faster than the other two types.

Lung cancer is by far the leading cause of cancer death among both men and women. Each year, more people die of lung cancer than of colon, breast, and prostate cancers combined. The American Cancer Society’s most recent estimates for lung cancer in the United States for 2012 reveal that about 226,160 new cases of lung cancer will be diagnosed (116,470 in men and 109,690 in women), and there will be an estimated 160,340 deaths from lung cancer (87,750 in men and 72,590 among women), accounting for about 28% of all cancer deaths.

Treatment

Different types of treatments are available for non-small cell lung cancer. Treatment depends on the stage of the cancer. For patients in whom the cancer has not spread to nearby lymph nodes are recommended surgery. Surgeon may remove- one of the lobes (lobectomy), only a small portion of the lung (wedge removal), or the entire lung (pneumonectomy). Some patients require chemotherapy that uses drugs to kill cancer cells and stop new cells from growing.

FDA approved drugs for NSCLC

Abitrexate (Methotrexate)
Abraxane (Paclitaxel Albumin-stabilized Nanoparticle Formulation) 
Alimta (Pemetrexed Disodium)
Avastin (Bevacizumab)
Bevacizumab
Carboplatin
Cisplatin
Crizotinib
Erlotinib Hydrochloride
Folex (Methotrexate)
Folex PFS (Methotrexate)
Gefitinib
Gemcitabine Hydrochloride
Gemzar (Gemcitabine Hydrochloride)
Iressa (Gefitinib)
Methotrexate
Methotrexate LPF (Methotrexate)
Mexate (Methotrexate)
Mexate-AQ (Methotrexate)
Paclitaxel
Paclitaxel Albumin-stabilized Nanoparticle Formulation
Paraplat (Carboplatin)
Paraplatin (Carboplatin)
Pemetrexed Disodium
Platinol (Cisplatin)
Platinol-AQ (Cisplatin)
Tarceva (Erlotinib Hydrochloride)
Taxol (Paclitaxel)
Xalkori (Crizotinib)

On the basis of target, the drugs have been classified as follows:

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NSCLC Drug Market Analysis

NSCLC drug market expected to grow from $4.2 billion in 2010 to $5.4 billion in 2020

Although, a whole list of agents is available for the treatment of NSCLC, the market for NSCLC drugs is expected to expand from $4.2 billion in 2010 to $5.4 billion in 2020 in the United States, France, Germany, Italy, Spain, the United Kingdom and Japan.   

However, drug sales for metastatic/advanced squamous cell non-small-cell lung cancer, which comprises only a small fraction of the market, will decrease from nearly 17 percent in 2010 to approximately 13 percent in 2020. According to surveyed U.S. oncologists and MCO pharmacy directors, increasing overall survival is one of the greatest unmet needs in first-line advanced squamous non-small-cell lung cancer.

In 2009, antimetabolites dominated the NSCLC market, with Eli Lilly’s Alimta (Pemetrexed) accounting for nearly three-quarters of sales within this drug class. Since then, Alimta has faced tough competition from a number of similar drugs and from emerging therapies. It was speculated that the antimetabolites market share would reduce significantly making it the second-largest drug class in NSCLC, while the epidermal growth factor receptor (EGFR) inhibitor class will garner the top market share by 2019.

Genentech/OSI Pharmaceuticals/Roche/Chugai Pharmaceutical’s Tarceva belongs to the EGFR inhibitor class, and has been prescribed principally along with Eli Lilly’s Alimta, to NSCLC patients.Both these drugs have dominated the NSCLC market till 2010, however, their market hold is expected to weaken from 2015-2020, as claimed by Decision Resources Analyst Karen Pomeranz, Ph.D. Decision Resources is a research and advisory firms for pharmaceutical and healthcare issues.

Tarceva (Erlotinib)

Generic Name: Erlotinib, Brand Name: Tarceva

Other Designation: CP 358774, OSI-774, R1415, RG1415, NSC 718781

Mechanism of Action: Tarceva, a small molecule quinazoline, directly and reversibly inhibits the epidermal growth factor receptor (EGFr) tyrosine kinase. Detailed information on how it works could be found at the Macmillian Cancer support website.

Tarceva has been approved for different cancers and several indications have been filed-

  • non-small cell lung cancer (nsclc), locally advanced or metastatic, second line, after failure of at least one prior chemotherapy regimen (2004)
  • pancreatic cancer, locally advanced or metastatic, in combination with gemcitabine, first line (2005)
  • non-small cell lung cancer (nsclc), advanced, maintenance therapy in responders following first line treatment with platinum-based chemotherapy (2010)
  • non-small cell lung cancer (nsclc) harboring epidermal growth factor (EGFr)-activating mutations, first line treatment in advanced disease

Sales of Tarceva 

May, 2012 sales of Tarceva in the US have been reported to be around $564.2 million.

In a recent article published by Vergnenègre et al in the Clinicoeconomic Outcomes Research journal (2012), cross-market cost-effectiveness of Erlotinib was analyzed. The study aimed at estimating the incremental cost-effectiveness of Erlotinib (150 mg/day) versus best supportive care when used as first-line maintenance therapy for patients with locally advanced or metastatic NSCLC and stable disease.

It was determined that treatment with erlotinib in first-line maintenance resulted in a mean life expectancy of 1.39 years in all countries, compared with a mean 1.11 years with best supportive care, which represents 0.28 life-years (3.4 life-months) gained with erlotinib versus best supportive care.

According to the authors analysis, there was a gain in the costs per-life year as $50,882, $60,025, and $35,669 in France, Germany, and Italy, respectively. Hence, on the basis of the study it was concluded that Erlotinib is a cost-effective treatment option when used as first-line maintenance therapy for locally advanced or metastatic NSCLC.

Avastin (Bevacizumab)

Generic Name: Avastin, Brand Name: Bevacizumab

Other Designation: rhuMAb-VEGF, NSC-704865, R435, RG435

Mechanism of Action

Bevacizumab is a recombinant humanized Mab antagonist of vascular endothelial growth factor A (VEGFA) acting as an angiogenesis inhibitor.

Targets

Vascular endothelial growth factor (VEGF, VEGF-A, VEGFA)

Avastin is the only currently approved VEGF inhibitor that selectively targets VEGF-A.

Three other approved oral drugs, pazopanib (Votrient; GlaxoSmithKline), sunitinib (Sutent; Pfizer) and sorafenib (Nexavar; Onyx Pharmaceuticals) are orally available multi-targeted receptor tyrosine kinase inhibitors that include VEGF receptors among their tar­gets.

Avastin has been approved for different cancers and several indications have been filed:

  • colorectal cancer, advanced, metastatic, first line, in combination with a 5-FU based chemotherapy regimen
  • colorectal cancer, relapsed, metastatic, second line, in combintion with 5-FU-based chemotherapy (2004)
  • non-small cell lung cancer (nsclc), non-squamous, inoperable, locally advanced, recurrent or metastatic, in combination with carboplatin and paclitaxel chemotherapy, first line (2006)
  • breast cancer, chemotherapy naive, first line, locally recurrent or metastatic, in combination with taxane chemotherapy (2008, revoked in 2011)
  • non-small cell lung cancer (nsclc), non-squamous, inoperable, locally advanced, recurrent or metastatic, in combination with platinum-based chemotherapy, first line
  • renal cell carcinoma (RCC), metastatic, in combination with interferon (IFN) alpha, first line (2009)
  • glioblastoma multiforme (GBM), relapsed after first line chemoradiotherapy
  • breast cancer, chemotherapy naive, first line, locally recurrent or metastatic, HEr2 negative, in combination with capecitabine (2009)
  • ovarian cancer, in combination with standard chemotherapy (carboplatin and paclitaxel) as a first line treatment following surgery for women with advanced (Stage IIIb/c or Stage IV) epithelial ovarian, primary peritoneal or fallopian tube cancer
  • ovarian cancer, in combination with carboplatin and gemcitabine as a treatment for women with recurrent, platinum-sensitive ovarian cancer

SOURCE:

New medicine Oncology Knowledge Base

Sales of Avastin 

As of May, 2012, sales of Avastin in the US have been reported to be around $2.66 billion.

It attracted a lot of attention over the past few years after its use as a breast cancer treatment. Avastin was approved by the FDA under its fast-track program. However, the data released by the FDA from follow-up studies led to questioning the use of Avastin as a breast cancer drug. Infact, Genentech pulled the indication from Avastin’s label. Henceforth, the FDA did cancel that approval in late 2011. Doctors, however, can still prescribe it off-label. Potential adverse effects of Avastin that came under scrutiny along with unfavorable cost benefit analyses might pose challenges to its growth potential and continued widespread use. However, the sales of Avastin have continued to increase and it has been reported by Fierce Pharma as one of the 15 best-selling cancer drugs list. (Fierce Pharma)

Dacomitinib: New promising drug for NSCLC

Generic Name: Dacomitinib

Other Designation: PF-299804, PF-00299804, PF-299,804, PF00299804

PF-299804 is an orally available irreversible pan-HEr tyrosine kinase inhibitor.

Dacomitinib is a promising new drug on the market. Phase III trials are ongoing for advanced and refractory NSCLC, locally advanced or metastatic NSCLC and the EGFr mutation containing locally advanced or metastatic NSCLC in several countries including those in Europe, Asia, and America.

SOURCE:

New medicine Oncology Knowledge base

Dacomitinib bests Erlotinib in advanced NSCLC:  Comparison of its Progression-Free Survival (PFS) with the NSCLC marketed drug, Erlotinib.

In September of 2012, a study was published by Ramalingam et al in the Journal of Clinical Oncology, which was a randomized open-label trial comparing dacomitinib with erlotinib in patients with advanced NSCLC. On the basis of the study it was concluded that dacomitinib demonstrated significantly improved progression-free survival (PFS*) as compared to erlotinib, with a certain degree of toxicity.

SOURCE:

Randomized Phase II Study of Dacomitinib Versus Erlotinib in Patients With Advanced Non-Small-Cell Lung Cancer

The results indicated indicated the following:

  • Median PFS was significantly greater with Dacomitinib than Erlotinib, at 2.86 versus 1.91.
  • Mean duration of response was 16.56 months for dacomitinib and 9.23 months for erlotinib.

Patients were divided into groups by tumor type and following results were obtained:

  • Median PFS was 3.71 months with dacomitinib and 1.91 with erlotinib in patients with KRAS wild-type tumors
  • Median PFS was 2.21 months and 1.68 months, in patients with KRAS wild-type/EGFR wild-type tumors.
  • PFS was significantly better in the molecular subgroups harboring a mutant EGFR genotype.

The study also highlighted the side effects which might be more of concern and probably limiting for Dacomitinib.

Although adverse side effects were uncommon in both the groups, certain side effects such as:

  • mouth sores,
  • nailbed infections, and
  • diarrhea

were more common and tended to be more severe with Dacomitinib as compared to Tarceva.

Therefore, for patients for whom side effects of Tarceva seem challenging might face more difficulty with Dacomitinib treatment. Nonetheless, the results of PFS were promising enough and provide a greater efficacy in several clinical and molecular subgroups targeting a larger population than Tarceva. Authors, thus, suggested a larger, randomized phase III trial with the same design.

Current status of Dacomitinib

Based on positive performance of Dacomitinib published in research studies, Pfizer has entered into a collaborative development agreement with the SFJ Pharmaceuticals Group to conduct a phase III clinical trial across multiple sites in Asia and Europe, to evaluate dacomitinib (PF-00299804) as a first line treatment in patients with locally advanced or metastatic non-small cell lung cancer (nsclc) with activating mutations in the epidermal growth factor receptor (EGFr). Under the terms of the agreement, SFJ will provide the funding and clinical development supervision to generate the clinical data necessary to support a registration dossier on Dacomitinib for marketing authorization by regulatory authorities for this indication. If approved for this indication, SFJ will be eligible to receive milestone and earn-out payments.

SOURCE:

New medicine Oncology Knowledge base

*PFS or Progression-free survival is defined as the length of time during and after the treatment of as disease, such as cancer, that a patient lives with the disease but it does not get worse. In a clinical trial, measuring the progression-free survival is one way to see how well a new treatment works.

REFERENCES

Recently, another drug PF-02341066 (crizotinib), was tested on patients with non-small cell lung cancer and the results were published in New England Journal of Medicine (2013). Crizotinib is an orally available aminopyridine-based inhibitor of the) and the c-Met/hepatocyte growth factor receptor (HGFR). Crizotinib, in an ATP-competitive manner, binds to and inhibits ALK kinase and ALK fusion proteins. In addition, crizotinib inhibits c-Met kinase, and disrupts the c-Met signaling pathway. Altogether, this agent inhibits tumor cell growth.

  • Shaw and colleagues (2013) investigated whether crizotinib is superior to standard chemotherapy with respect to efficacy. To answer the question, Pfizer launched a phase III clinical trial (NCT00932893; http://clinicaltrials.gov/show/NCT00932893) comparing the safety and anti-tumor activity of PF-02341066 (crizotinib) versus pemetrexed or docetaxel in patients with advanced non-small cell lung cancer harboring a translocation or inversion event involving the ALK gene. Shaw and colleagues (2013) published the results of the clinical trial in a recent issue of New England Journal of Medicine.  A total of 347 patients with locally advanced or metastatic ALK-positive lung cancer who had received one prior platinum-based regimen were recruited for the trial and patients were randomly assigned to receive oral treatment with crizotinib (250 mg) twice daily or intravenous chemotherapy with either pemetrexed (500 mg per square meter of body-surface area) or docetaxel (75 mg per square meter) every 3 weeks. Patients in the chemotherapy group who had disease progression were permitted to cross over to crizotinib as part of a separate study. The primary end point was progression-free survival. According to the results, the median progression-free survival was 7.7 months in the crizotinib group and 3.0 months in the chemotherapy group. Hazard ratio (HR) for progression or death with crizotinib was 0.49 (95% CI, P<0.001). The response rates were 65% with crizotinib, as compared with 20% with chemotherapy (P<0.001). An interim analysis of overall survival showed no significant improvement with crizotinib as compared with chemotherapy (hazard ratio for death in the crizotinib group, 1.02; 95% CI, P=0.54). Common adverse events associated with crizotinib were visual disorder, gastrointestinal side effects, and elevated liver aminotransferase levels, whereas common adverse events with chemotherapy were fatigue, alopecia, and dyspnea. Patients reported greater reductions in symptoms of lung cancer and greater improvement in global quality of life with crizotinib than with chemotherapy.In conclusion, the results from the trial indicate that crizotinib is superior to standard chemotherapy in patients with previously treated, advanced non–small-cell lung cancer with ALK rearrangement. (Shaw AT, et al, Crizotinib versus Chemotherapy in Advanced ALK-Positive Lung Cancer. N Engl J Med 2013; 20 June, 368:2385-2394; http://www.ncbi.nlm.nih.gov/pubmed/23724913).

However, in the same issue of New England Journal of Medicine, Awad and colleagues (2013) reported from a phase I clinical trial (NCT00585195; http://clinicaltrials.gov/show/NCT00585195), that a patient with metastatic lung adenocarcioma harboring a CD74-ROS1 rearrangement who had initially shown a dramatic response to treatment, showed resistance to crizotinib. Biopsy of the resistant tumor identified an acquired mutation leading to a glycine-to-arginine substitution at codon 2032 in the ROS1 kinase domain. Although this mutation does not lie at the gatekeeper residue, it confers resistance to ROS1 kinase inhibition through steric interference with drug binding. The same resistance mutation was observed at all the metastatic sites that were examined at autopsy, suggesting that this mutation was an early event in the clonal evolution of resistance. The study was funded by Pfizer (Awad MM, et al, Acquired resistance to crizotinib from a mutation in CD74-ROS1. N Engl J Med. 2013 Jun 20;368(25):2395-401; http://www.ncbi.nlm.nih.gov/pubmed/23724914)

Reference: 

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Larry H Bernstein, MD, FCAP,  Reporter

Lipid Profile Predicts Metastasis in Breast Cancer

Posted on October 24, 2012 by admin

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Researchers at the Bellvitge Biomedical Research Institute (IDIBELL) and The Institute of Photonic Sciences (ICFO) have collaborated on the development of a diagnostic tool that identifies the metastatic ability of breast cancer cells. The analysis is based on the characterization of the lipid component of the cells, which is indicative of malignancy. This has allowed the researchers to develop a classifier to discriminate cells capable of inducing metastasis. The results of the study have been published in the online version of the scientific journal PLoS ONE.

The characterization of the lipids associated with malignancy has been possible thanks to the technological development of a spectroscopic device named Raman along with the versatility offered by the experimental models of breast cancer. The results of this process form the basis for introducing this technique in routine cytological diagnosis, which could be extended in the future to diagnose other tumors.

Lipids

Lipids (Photo credit: AJC1)

English: Breast cancer incidence by age in wom...

English: Breast cancer incidence by age in women in the United Kingdom 2006-2008. Reference: Excel chart for Figure 1.1: Breast Cancer (C50), Average Number of New Cases per Year and Age-Specific Incidence Rates, UK, 2006-2008 at Breast cancer – UK incidence statistics at Cancer Research UK. Section updated 18/07/11. (Photo credit: Wikipedia)

The researchers have analyzed the main components and, partly, the less discriminating ones to assess the profile of the lipid composition of breast cancer cells. They have generated a classification model that segregated metastatic and non-metastatic cells. “The algorithm for the discrimination of the metastatic ability is a first step toward the stratification of breast cancer cells using this quick and reactive tool,” explains the study coordinator, Àngels Sierra, researcher at the Biological Clues of the Invasive and Metastatic Phenotype group of IDIBELL.

Using cytology techniques, the researchers have found a correlation between the activation of lipogenesis (the chemical reaction leading to fatty acids in an organism) and the amount of saturated fats in metastatic cells indicating a worse prognosis and a decreased survival. The lipid content of the breast cancer cells might be a useful measure to determine various functions coupled to the progression of breast cancer. The work has been supported by the Instituto de Salud Carlos III, the former Spanish Ministry of Science and Innovation and the private Cellex Barcelona Foundation.

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Author and Reporter: Ritu Saxena, Ph.D.  

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Word Cloud By Danielle Smolyar

Mitochondria is an important cell organelle that is associated with several key cellular functions as energy production, anabolism, calcium homeostasis and cell programmed death, and any abnormalities occurring in mitochondria would lead to alteration of normal cellular function.

Role of mitochondria in cancer has long been implicated. Post published on September 1, 2012 (http://pharmaceuticalintelligence.com/2012/09/01/mitochondria-and-cancer-an-overview/) presents a brief overview of the mechanisms by which mitochondrial defects could be associated with cancer. Different studies on various types of Cancers have tried to determine the mtDNA mutations and the mechanisms involved. An important aspect of cancerous progression is the cancer cell migration and it has been observed that mitochondrial dysfunction is involved in cancer cell migration. However, the molecular mechanism still needs to be deciphered.

A group from Taiwan recently published their findings in the Biochimica et Biophysica Acta journal stating that enhanced β5-integrin expression was involved in promoting cell migration in human gastric cancer cell line as a result of mitochondrial dysfunction.

The authors used human gastric cancer cell line, SC-M1 cells for their studies. The methodology followed was to first create mitochondrial dysfunction in the SC-M1 cells by the use of oxidative phosphorylation inhibitors: oligomycin (Complex V inhibitor) and antimycin A (Complex III inhibitor) thereby inhibiting mitochondrial function. The results indicated that impaired oxidative phosphorylation caused an increase in the intracellular Reactive Oxygen Species (ROS) that lead to an increased cell migration in SC-M1 cells.

Different types of integrin molecules have been implicated in cell migration. Hung et al extracted RNA and protein from SC-M1 cells in order to study the different types of integrins, and observed that the levels of β5-integrin were significantly upregulated in SC-M1 cells.  Simultaneously, the surface expression of the dimer- β5-integrin and αv-integrin, was studied in cancer cells with using FACS. The analysis revealed a higher surface expression of the dimer corresponding to the higher levels of the protein and RNA results of  β5-integrin expression in SC-M1 cells with mitochondrial dysfunction. Infact, a subpopulation of SC-M1 cells that showed higher migration capability (SC-M1-3rd) was observed to harbor a higher lever of β5-integrin expression, correlating β5-integrin expression with cell migration ability. The experiments supported the role of β5-integrin in cell migration in gastric cancer cells.

Finally, authors confirmed the in vitro results in the human gastric cancer samples. Immunohistochemical analysis revealed that β5-integrin was stained positive in around 73% of the cancer samples. Additionally, the higher expression levels of β5-integrin could be correlated with the invasive ability and more aggressive behavior of gastric cancer cells.

Authors stated “our study pinpoints another aspect that links the induction of intracellular ROS level in mitochondrial dysfunction gastric cancer cells with the activation of αvβ5-integrin. Taken together, the induction of β5-integrin is important to gastric cancer metastasis, especially in cancer cells that exhibit mitochondrial dysfunction.”

Thus, blockage of αvβ5-integrin function by antibodies might be tested as a potential therapy for preventing or delaying gastric cancer metastasis, especially in gastric cancers harboring mitochondrial dysfunction.

Sources:

Research article: http://www.ncbi.nlm.nih.gov/pubmed?term=22561002

Related posts: http://pharmaceuticalintelligence.com/2012/09/01/mitochondria-and-cancer-an-overview/

http://pharmaceuticalintelligence.com/2012/09/06/clinical-genetics-personalized-medicine-molecular-diagnostics-consumer-targeted-dna-consumer-genetics-conference-cgc-october-3-5-2012-seaport-hotel-boston-ma/

http://pharmaceuticalintelligence.com/2012/08/14/detecting-potential-toxicity-in-mitochondria/

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