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Lesson 9 Cell Signaling:  Curations and Articles of reference as supplemental information for lecture section on WNTs: #TUBiol3373

Stephen J. Wiilliams, Ph.D: Curator

The following contain curations of scientific articles from the site https://pharmaceuticalintelligence.com  intended as additional reference material  to supplement material presented in the lecture.

Wnts are a family of lipid-modified secreted glycoproteins which are involved in:

Normal physiological processes including

A. Development:

– Osteogenesis and adipogenesis (Loss of wnt/β‐catenin signaling causes cell fate shift of preosteoblasts from osteoblasts to adipocytes)

  – embryogenesis including body axis patterning, cell fate specification, cell proliferation and cell migration

B. tissue regeneration in adult tissue

read: Wnt signaling in the intestinal epithelium: from endoderm to cancer

And in pathologic processes such as oncogenesis (refer to Wnt/β-catenin Signaling [7.10]) and to your Powerpoint presentation

 

The curation Wnt/β-catenin Signaling is a comprehensive review of canonical and noncanonical Wnt signaling pathways

 

To review:

 

 

 

 

 

 

 

 

 

 

 

Activating the canonical Wnt pathway frees B-catenin from the degradation complex, resulting in B-catenin translocating to the nucleus and resultant transcription of B-catenin/TCF/LEF target genes.

Fig. 1 Canonical Wnt/FZD signaling pathway. (A) In the absence of Wnt signaling, soluble β-catenin is phosphorylated by a degradation complex consisting of the kinases GSK3β and CK1α and the scaffolding proteins APC and Axin1. Phosphorylated β-catenin is targeted for proteasomal degradation after ubiquitination by the SCF protein complex. In the nucleus and in the absence of β-catenin, TCF/LEF transcription factor activity is repressed by TLE-1; (B) activation of the canonical Wnt/FZD signaling leads to phosphorylation of Dvl/Dsh, which in turn recruits Axin1 and GSK3β adjacent to the plasma membrane, thus preventing the formation of the degradation complex. As a result, β-catenin accumulates in the cytoplasm and translocates into the nucleus, where it promotes the expression of target genes via interaction with TCF/LEF transcription factors and other proteins such as CBP, Bcl9, and Pygo.

NOTE: In the canonical signaling, the Wnt signal is transmitted via the Frizzled/LRP5/6 activated receptor to INACTIVATE the degradation complex thus allowing free B-catenin to act as the ultimate transducer of the signal.

Remember, as we discussed, the most frequent cancer-related mutations of WNT pathway constituents is in APC.

This shows how important the degradation complex is in controlling canonical WNT signaling.

Other cell signaling systems are controlled by protein degradation:

A.  The Forkhead family of transcription factors

Read: Regulation of FoxO protein stability via ubiquitination and proteasome degradation

B. Tumor necrosis factor α/NF κB signaling

Read: NF-κB, the first quarter-century: remarkable progress and outstanding questions

1.            Question: In cell involving G-proteins, the signal can be terminated by desensitization mechanisms.  How is both the canonical and noncanonical Wnt signal eventually terminated/desensitized?

We also discussed the noncanonical Wnt signaling pathway (independent of B-catenin induced transcriptional activity).  Note that the canonical and noncanonical involve different transducers of the signal.

Noncanonical WNT Signaling

Note: In noncanonical signaling the transducer is a G-protein and second messenger system is IP3/DAG/Ca++ and/or kinases such as MAPK, JNK.

Depending on the different combinations of WNT ligands and the receptors, WNT signaling activates several different intracellular pathways  (i.e. canonical versus noncanonical)

 

In addition different Wnt ligands are expressed at different times (temporally) and different cell types in development and in the process of oncogenesis. 

The following paper on Wnt signaling in ovarian oncogenesis shows how certain Wnt ligands are expressed in normal epithelial cells but the Wnt expression pattern changes upon transformation and ovarian oncogenesis. In addition, differential expression of canonical versus noncanonical WNT ligands occur during the process of oncogenesis (for example below the authors describe the noncanonical WNT5a is expressed in normal ovarian  epithelia yet WNT5a expression in ovarian cancer is lower than the underlying normal epithelium. However the canonical WNT10a, overexpressed in ovarian cancer cells, serves as an oncogene, promoting oncogenesis and tumor growth.

Wnt5a Suppresses Epithelial Ovarian Cancer by Promoting Cellular Senescence

Benjamin G. Bitler,1 Jasmine P. Nicodemus,1 Hua Li,1 Qi Cai,2 Hong Wu,3 Xiang Hua,4 Tianyu Li,5 Michael J. Birrer,6Andrew K. Godwin,7 Paul Cairns,8 and Rugang Zhang1,*

A.           Abstract

Epithelial ovarian cancer (EOC) remains the most lethal gynecological malignancy in the US. Thus, there is an urgent need to develop novel therapeutics for this disease. Cellular senescence is an important tumor suppression mechanism that has recently been suggested as a novel mechanism to target for developing cancer therapeutics. Wnt5a is a non-canonical Wnt ligand that plays a context-dependent role in human cancers. Here, we investigate the role of Wnt5a in regulating senescence of EOC cells. We demonstrate that Wnt5a is expressed at significantly lower levels in human EOC cell lines and in primary human EOCs (n = 130) compared with either normal ovarian surface epithelium (n = 31; p = 0.039) or fallopian tube epithelium (n = 28; p < 0.001). Notably, a lower level of Wnt5a expression correlates with tumor stage (p = 0.003) and predicts shorter overall survival in EOC patients (p = 0.003). Significantly, restoration of Wnt5a expression inhibits the proliferation of human EOC cells both in vitro and in vivo in an orthotopic EOC mouse model. Mechanistically, Wnt5a antagonizes canonical Wnt/β-catenin signaling and induces cellular senescence by activating the histone repressor A (HIRA)/promyelocytic leukemia (PML) senescence pathway. In summary, we show that loss of Wnt5a predicts poor outcome in EOC patients and Wnt5a suppresses the growth of EOC cells by triggering cellular senescence. We suggest that strategies to drive senescence in EOC cells by reconstituting Wnt5a signaling may offer an effective new strategy for EOC therapy.

Oncol Lett. 2017 Dec;14(6):6611-6617. doi: 10.3892/ol.2017.7062. Epub 2017 Sep 26.

Clinical significance and biological role of Wnt10a in ovarian cancer. 

Li P1Liu W1Xu Q1Wang C1.

Ovarian cancer is one of the five most malignant types of cancer in females, and the only currently effective therapy is surgical resection combined with chemotherapy. Wnt family member 10A (Wnt10a) has previously been identified to serve an oncogenic function in several tumor types, and was revealed to have clinical significance in renal cell carcinoma; however, there is still only limited information regarding the function of Wnt10a in the carcinogenesis of ovarian cancer. The present study identified increased expression levels of Wnt10a in two cell lines, SKOV3 and A2780, using reverse transcription-polymerase chain reaction. Functional analysis indicated that the viability rate and migratory ability of SKOV3 cells was significantly inhibited following Wnt10a knockdown using short interfering RNA (siRNA) technology. The viability rate of SKOV3 cells decreased by ~60% compared with the control and the migratory ability was only ~30% of that in the control. Furthermore, the expression levels of β-catenin, transcription factor 4, lymphoid enhancer binding factor 1 and cyclin D1 were significantly downregulated in SKOV3 cells treated with Wnt10a-siRNA3 or LGK-974, a specific inhibitor of the canonical Wnt signaling pathway. However, there were no synergistic effects observed between Wnt10a siRNA3 and LGK-974, which indicated that Wnt10a activated the Wnt/β-catenin signaling pathway in SKOV3 cells. In addition, using quantitative PCR, Wnt10a was overexpressed in the tumor tissue samples obtained from 86 patients with ovarian cancer when compared with matching paratumoral tissues. Clinicopathological association analysis revealed that Wnt10a was significantly associated with high-grade (grade III, P=0.031) and late-stage (T4, P=0.008) ovarian cancer. Furthermore, the estimated 5-year survival rate was 18.4% for patients with low Wnt10a expression levels (n=38), whereas for patients with high Wnt10a expression (n=48) the rate was 6.3%. The results of the present study suggested that Wnt10a serves an oncogenic role during the carcinogenesis and progression of ovarian cancer via the Wnt/β-catenin signaling pathway.

Targeting the Wnt Pathway includes curations of articles related to the clinical development of Wnt signaling inhibitors as a therapeutic target in various cancers including hepatocellular carcinoma, colon, breast and potentially ovarian cancer.

 

2.         Question: Given that different Wnt ligands and receptors activate different signaling pathways, AND  WNT ligands  can be deferentially and temporally expressed  in various tumor types and the process of oncogenesis, how would you approach a personalized therapy targeting the WNT signaling pathway?

3.         Question: What are the potential mechanisms of either intrinsic or acquired resistance to Wnt ligand antagonists being developed?

 

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

Targeting the Wnt Pathway [7.11]

Wnt/β-catenin Signaling [7.10]

Cancer Signaling Pathways and Tumor Progression: Images of Biological Processes in the Voice of a Pathologist Cancer Expert

e-Scientific Publishing: The Competitive Advantage of a Powerhouse for Curation of Scientific Findings and Methodology Development for e-Scientific Publishing – LPBI Group, A Case in Point 

Electronic Scientific AGORA: Comment Exchanges by Global Scientists on Articles published in the Open Access Journal @pharmaceuticalintelligence.com – Four Case Studies

 

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Moderna Therapeutics Deal with Merck: Are Personalized Vaccines here?

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

Take aways:

  • RNA based vaccines are a cost-effective method of developing and manufacturing a personalized cancer vaccine strategy; traditional vaccine methodology has not been met with much success as a cancer therapeutic
  • Most of the older RNA vaccine technology depended on isolated dendritic cells or T cell populations and ex-vivo treatment with RNA vaccine, HOWEVER, Moderna has developed a technology that circumvents the need for ex-vivo vaccination
  • There are multiple companies involved in this new RNA strategy (Moderna, Caperna {now Moderna}, CureVac, Biontech)

From BusinessWire at http://www.businesswire.com/news/home/20160629005446/en/Merck-Moderna-Announce-Strategic-Collaboration-Advance-mRNA-Based

Merck and Moderna Announce Strategic Collaboration to Advance Novel mRNA-Based Personalized Cancer Vaccines with KEYTRUDA®(pembrolizumab) for the Treatment of Multiple Types of Cancer

Collaboration Combines Merck’s Leadership in Immuno-Oncology with Moderna’s Pioneering mRNA Vaccine Technology and Rapid Cycle Time, Small-Batch GMP Manufacturing Capabilities

KENILWORTH, N.J. & CAMBRIDGE, Mass.–(BUSINESS WIRE)–Merck (NYSE:MRK), known as MSD outside the United States and Canada, and Moderna Therapeutics today announced a strategic collaboration and license agreement to develop and commercialize novel messenger RNA (mRNA)-based personalized cancer vaccines. The collaboration will combine Merck’s established leadership in immuno-oncology with Moderna’s pioneering mRNA vaccine technology and GMP manufacturing capabilities to advance individually tailored cancer vaccines for patients across a spectrum of cancers.

“Combining immunotherapy with vaccine technology may be a new path toward improving outcomes for patients”

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Moderna and Merck will develop personalized cancer vaccines that utilize Moderna’s mRNA vaccine technology to encode a patient’s specific neoantigens, unique mutations present in that specific patient’s tumor. When injected into a patient, the vaccine will be designed to elicit a specific immune response that will recognize and destroy cancer cells. The companies believe that the mRNA-based personalized cancer vaccines’ ability to specifically activate an individual patient’s immune system has the potential to be synergistic with checkpoint inhibitor therapies, including Merck’s anti-PD-1 therapy, KEYTRUDA® (pembrolizumab). In addition, Moderna has developed a rapid cycle time, small-batch manufacturing technique that will uniquely allow the company to supply vaccines tailored to individual patients within weeks.

Under the terms of the agreement, Merck will make an upfront cash payment to Moderna of $200 million, which Moderna will use to lead all research and development efforts through proof of concept. The development program will entail multiple studies in several types of cancer and include the evaluation of mRNA-based personalized cancer vaccines in combination with Merck’s KEYTRUDA® (pembrolizumab). Moderna will also utilize the upfront payment to fund a portion of the build-out of a GMP manufacturing facility in suburban Boston for the purpose of personalized cancer vaccine manufacturing.

Following human proof of concept studies, Merck has the right to elect to make an additional undisclosed payment to Moderna. If exercised, the two companies will then equally share cost and profits under a worldwide collaboration for the development of personalized cancer vaccines. Moderna will have the right to elect to co-promote the personalized cancer vaccines in the U.S. The agreement entails exclusivity around combinations with KEYTRUDA. Moderna and Merck will each have the ability to combine mRNA-based personalized cancer vaccines with other (non-PD-1) agents.

Combining immunotherapy with vaccine technology may be a new path toward improving outcomes for patients,” said Dr. Roger Perlmutter, President, Merck Research Laboratories. “While the area of personalized cancer vaccine research has faced challenges in the past, there have been many recent advances, and we believe that working with Moderna to combine an immuno-oncology approach, using KEYTRUDA, with mRNA-based personalized cancer vaccines may have the potential to transform the treatment of cancer.”

“Our team has made significant progress since beginning our work in personalized cancer vaccines just last year. Through this collaboration with Merck, we are now well-positioned to accelerate research and development with a goal of entering the clinic in 2017, as well as to apply our unique GMP manufacturing capabilities to support the rapid production of these highly individualized vaccines,” said Stéphane Bancel, chief executive officer of Moderna. “We value our continued collaboration with Merck, and we look forward to working together to harness the potential of personalized cancer vaccines and immuno-oncology to bring a new treatment paradigm to patients.”

Merck and Moderna have an existing collaboration and license agreement focused on the discovery and development of mRNA-based infectious disease vaccines and passive immunity treatments. Moderna is also advancing its own pipeline of infectious disease vaccine candidates and currently has two phase 1 studies underway in Europe and the U.S.

About Moderna Therapeutics

Moderna is a clinical stage pioneer of messenger RNA Therapeutics™, an entirely new in vivo drug technology that produces human proteins, antibodies and entirely novel protein constructs inside patient cells, which are in turn secreted or active intracellularly. This breakthrough platform addresses currently undruggable targets and offers a potentially superior alternative to existing drug modalities for a wide range of diseases and conditions. Moderna is developing and plans to commercialize its innovative mRNA drugs through its own ventures and its strategic relationships with established pharmaceutical and biotech companies. Its current ventures are:

  • Onkaido, focused on oncology,
  • Valera, focused on infectious diseases,
  • Elpidera, focused on rare diseases, and
  • Caperna, focused on personalized cancer vaccines.

Cambridge-based Moderna is privately held and currently has strategic agreements with AstraZeneca, Alexion Pharmaceuticals and Merck. To learn more, visit www.modernatx.com.

From the Moderna Therapeutics Website

Our mRNA Platform

At Moderna, we are pioneering the development of a new class of drugs made of messenger RNA (mRNA). This novel drug platform builds on the discovery that modified mRNA can direct the body’s cellular machinery to produce nearly any protein of interest, from native proteins to antibodies and other entirely novel protein constructs that can have therapeutic activity inside and outside of cells.

Our efforts are helping Moderna and the industry to flatten the mRNA learning curve across the full breadth of competencies needed to drive the platform forward, including chemistry, mRNA biology, formulation, process development, automation and high-throughput production, quality, and Good Manufacturing Practice (GMP) manufacturing.

Drug Modalities

Building from our mRNA core expression platform, we have created a new scale of drug discovery and development that enables a series of new drug modalities. Each modality represents a distinct approach to using the mRNA platform to encode proteins that achieve a therapeutic benefit, enabling us to develop numerous drug candidates across a wide array of therapeutic areas.

Vaccines

Vaccines are substances that teach the immune system to rapidly recognize and destroy invading pathogens such as bacteria or viruses, preparing the body’s adaptive immunity for future exposure to the pathogen. Historically, vaccines have introduced immune-activating markers from pathogens into the body. Conversely, Moderna is developing mRNA-based vaccines that enable the body to produce and present immunogenic proteins to the immune system.

Moderna is also developing mRNA-based personalized cancer vaccines to prime the immune system to recognize cancer cells and mount a strong, tailored response to each individual patient’s cancer. Moderna’s technology allows for a rapid turn-around time in production of these unique mRNA vaccines.

Intracellular/Transmembrane

Many diseases are caused by defects in proteins that function inside cells. Existing methods of protein-based therapy do not allow for proteins to reach the intracellular space, and as such are unable to replace the defective, disease-causing proteins within cells. Moderna’s platform allows for the development of mRNA therapies that can stimulate production of intracellular proteins as well as transmembrane proteins. This could potentially lead to a novel approach to treating a vast array of rare genetic and other diseases caused by intracellular protein defects.

Intratumoral

Many targets for the treatment of cancer have been identified but their therapeutic potential has been limited by either the inability to access these targets, or by systemic toxicities. Moderna’s platform allows for localized expression of therapeutic proteins within the tumor microenvironment.

Secreted antibodies

Antibodies are secreted proteins that bind to and inhibit specific targets. Moderna’s platform has the potential to stimulate the body’s own cells to produce specific antibodies that can bind to cellular targets.

Secreted proteins

Proteins are large, complex molecules that have many critical functions both inside and outside of cells. Moderna’s platform stimulates cells to produce and secrete proteins that can have a therapeutic benefit through systemic exposure.

Moderna is comprised of four smaller companies, the following three are involved in their personalized immunotherapy and cancer vaccine strategy

Caperna LLC

Caperna

Caperna LLC is the fourth Moderna venture company — formed, funded and wholly-owned by Moderna — and focused exclusively on the advancement of personalized cancer vaccines.

Caperna will apply Moderna’s mRNA vaccine technology to the field of cancer vaccines, building on advances in recent years in cancer immunotherapy. Utilizing Moderna’s demonstrated engineering and process capability to synthesize over 1,000 unique novel mRNA’s per month in Moderna’s, automated, in-house productions systems. This provides the basis for a vision of rapid turnaround times that will allow Caperna’s personalized cancer vaccine, customized after tumor biopsy and sequencing to code for specific neoantigens in patients’ tumors, to be used to treat patients with aggressive tumors and high unmet need (rather than those with less aggressive tumors which can’t wait for prolonged turnaround times). Caperna will develop its personalized cancer vaccines in combination with checkpoint inhibitors that unleash the immune system and other cancer immunotherapies.

Corporate Facts

  • President: Tal Zaks, M.D., Ph.D.
  • Head of Research: Nicholas Valiante, Ph.D.
  • Head of Operations: Ted Ashburn, M.D., Ph.D.
  • Headquarters: 500 Technology Square, Cambridge, Mass.
  • Phone: 617-714-6500
  • Website: Caperna.com

 

Onkaido

Onkaido

Onkaido Therapeutics is the first Moderna venture company – formed, funded and wholly-owned by Moderna. Onkaido is focused exclusively on developing mRNA-based oncology treatments for currently undruggable targets or as a superior alternative to existing drug modalities. Onkaido is leveraging all of the tools and modalities developed at Moderna, with plans to rapidly turn mRNA science into truly novel cancer therapies that can make a real difference for patients.

Onkaido is currently focused on three therapeutic areas of oncology drug discovery and development: immuno-oncology, hepatocellular carcinoma (liver cancer) and myeloid malignancies – with programs investigating multiple targets and therapies simultaneously. Onkaido scientists are also exploring the power of mRNA technology in precision cancer pharmacology – researching areas such as tumor biology, targeting and gene silencing, driving the science toward the delivery of truly personalized cancer treatment.

Corporate Facts

  • President: Stephen Kelsey, M.D.
  • Headquarters: 500 Technology Square, Cambridge, Mass.
  • Phone: 617-714-6500
  • Website: Onkaido.com

 

Valera

Valera

Valera LLC is the second Moderna venture company — formed, funded and wholly-owned by Moderna — and focused exclusively on the advancement of vaccines and therapeutics for the prevention and treatment of viral, bacterial and parasitic infectious diseases.

The vaccines work of Valera builds on a body of preclinical research at Moderna showing the ability of modified mRNA to express viral antigens in vivo and to induce robust immune responses. Valera’s therapeutic passive immunity programs will expand on Moderna’s research using mRNA to express antibodies that bind to viral and other targets. The robust data from these programs across a range of preclinical infectious disease models, together with the inherent, rapid turn-around time in creating novel mRNA constructs, provide Valera with a potentially powerful and versatile new platform for the creation of a broad array of vaccines and passive immunity therapies.

Corporate Facts

  • President: Michael Watson, MB ChB, MRCP, AFPM
  • Chief Scientific OfficerGiuseppe Ciaramella, Ph.D.
  • Interim Chief Medical OfficerTal Zaks, M.D., Ph.D.
  • Headquarters: 500 Technology Square, Cambridge, Mass.
  • Phone: 617-714-6500
  • Website: Valeratx.com

And from http://endpts.com/neoantigens-beckon-merck-into-a-200m-cancer-collaboration-with-moderna/

Neoantigens beckon Merck into a $200M cancer collaboration with Moderna


Now that Galena has added fresh evidence that first-gen cancer vaccines make for a poor R&D program, Merck is betting $200 million upfront that the next-gen neoantigen approach to personalized cancer vaccines can succeed where all else has failed.

Merck is tying up with the mRNA specialists at Cambridge, MA-based Moderna, which has inked a long lineup of marquee partnerships. The big idea here is that each person’s cancer cells present unique “neoantigens” that can be used to tailor a cancer vaccine for each patient.

That’s a radical idea that has gained considerable steam in recent months, with Gritstone and Neon Therapeutics — paired now with Bristol-Myers on Opdivo — rounding up significant venture cash. Biotech billionaire Patrick Soon-Shiong has also jumped into the game, including it in its growing slate of cancer R&D work in a group of startups.

Moderna says it has already set up a manufacturing system that can be used to create these personalized vaccines in a matter of weeks. And Merck will use the partnership to advance new combination therapies that include its checkpoint inhibitor Keytruda.

The way the deal works, Moderna notes in its statement, is that Merck can step up after it sees some evidence in humans that the tech is working as planned. After human proof-of-concept, if Merck wants to opt in they can pay a significant milestone and then both companies can share the cost on Phase III and commercializations, profiting equally.Moderna CEO Stéphane Bancel says they can jump into the clinic next year.

The deal marks another rare pact by Merck R&D chief Roger Perlmutter, who’s been carefully focused on making Keytruda a foundation franchise that can sustain the company for years to come. While Merck has been a couple of steps behind Bristol-Myers in gaining market share, Perlmutter’s not settling for a second place finish.

“Combining immunotherapy with vaccine technology may be a new path toward improving outcomes for patients,” said Perlmutter, president, Merck Research Laboratories. “While the area of personalized cancer vaccine research has faced challenges in the past, there have been many recent advances, and we believe that working with Moderna to combine an immuno-oncology approach, using KEYTRUDA, with mRNA-based personalized cancer vaccines may have the potential to transform the treatment of cancer.”

From FierceBiotech on failure of Galena’s breast cancer vaccine trial

Galena plummets into microcap territory on Phase III breast cancer vaccine trial halt

Immunother Cancer. 2015; 3: 26.
Published online 2015 Jun 16. doi:  10.1186/s40425-015-0068-y
PMCID: PMC4468959

Self-adjuvanted mRNA vaccination in advanced prostate cancer patients: a first-in-man phase I/IIa study

Klinikum rechts der Isar der Technischen Universität München, Munich, Germany
CureVac GmbH, Paul-Ehrlich-Str. 15, Tuebingen, 72076 Germany
Charité University Hospital Berlin, Berlin, Germany
University Hospital Freiburg, Freiburg, Germany
Universitäty Hospital Essen, Essen, Germany
San Raffaele Scientific Institute, Milan, Italy
University Hospital of the Johannes-Gutenberg-University Mainz, Mainz, Germany
Ortenau Klinikum Offenburg-Gengenbach, Offenburg, Germany
University Hospital Göttingen, Göttingen/University Hospital Mannheim, Mannheim, Germany
University Hospital Schleswig-Holstein Campus Luebeck, Luebeck, Germany
Rippin-Consulting, Solingen, Germany
University Hospital Tuebingen, Tuebingen, Germany
Hubert Kübler, ed.nehcneum-ut.zrl@relbeuK.H.
corresponding authorCorresponding author.
#Contributed equally.

Abstract

Background

CV9103 is a prostate-cancer vaccine containing self-adjuvanted mRNA (RNActive®) encoding the antigens PSA, PSCA, PSMA, and STEAP1. This phase I/IIa study evaluated safety and immunogenicity of CV9103 in patients with advanced castration-resistant prostate-cancer.

Methods

44 Patients received up to 5 intra-dermal vaccinations. Three dose levels of total mRNA were tested in Phase I in cohorts of 3–6 patients to determine a recommended dose. In phase II, 32 additional patients were treated at the recommended dose. The primary endpoint was safety and tolerability, the secondary endpoint was induction of antigen specific immune responses monitored at baseline and at weeks 5, 9 and 17.

Results

The most frequent adverse events were grade 1/2 injection site erythema, injection site reactions, fatigue, pyrexia, chills and influenza-like illness. Possibly treatment related urinary retention occurred in 3 patients. The recommended dose was 1280 μg. A total of 26/33 evaluable patients treated at 1280 μg developed an immune response, directed against multiple antigens in 15 out of 33 patients. One patient showed a confirmed PSA response. In the subgroup of 36 metastatic patients, the Kaplan-Meier estimate of median overall survival was 31.4 months [95 % CI: 21.2; n.a].

Conclusions

The self-adjuvanted RNActive® vaccine CV9103 was well tolerated and immunogenic.

The technology is a versatile, fast and cost-effective platform allowing for creation of vaccines. The follow-up vaccine CV9104 including the additional antigens prostatic acid phosphatase (PAP) and Muc1 is currently being tested in a randomized phase IIb trial to assess the clinical benefit induced by this new vaccination approach.

SOURCE

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4468959/

Other articles in the Open Access Journal on Cancer Vaccines Include:

Cancer Vaccines: Targeting Cancer Genes for Immunotherapy – A Conference by Keystone Symposia on Molecular and Cellular Biology

AACR2016 – Cancer immunotherapy

Aduro Biotech Phase II Pancreatic Cancer Trial CRS-207 plus cancer vaccine GVAX Fails

Cases in Biotech Entrepreneurship: Selective Start Ups in 2016

at #JPM16 – Moderna Therapeutics turns away an extra $200 million: with AstraZeneca (collaboration) & with Merck ($100 million investment)

 

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How cancer metastasis occurs

Larry H. Bernstein, MD, FCAP, Curator

LPBI

 

How Cancer Cells Slide along Narrow Path to Metastasis

http://www.genengnews.com/gen-news-highlights/how-cancer-cells-slide-along-narrow-path-to-metastasis/81252674/

In tumors, abnormal protein-fiber environments and genetic perturbations conspire to give rise to metastatic behavior. In this looking-glass world, cells that bump into each other do not halt and reverse direction, as they ordinarily would. Instead, they slide around each other, enhancing migratory potential and bringing to mind the portmanteau “slithy,” which Lewis Carroll invented to describe the behavior of some of his imaginary creatures.

Slithy cancer cells do gyre and gimble in the tumor microenvironment, a looking-glass world in which abnormal protein-fiber scaffolds and genetic perturbations coincide, creating conditions that promote metastasis. Some cancer cells manage to circumnavigate or slide around other cells on protein fibers, and these cells can take relatively straightforward paths out of a primary tumor. Other cells, however, are more likely to turn back upon encountering other cells. They exit tumors less efficiently.

To understand how some cancer cells migrate more efficiently than others, researchers based at Northeastern University undertook a biophysical study. They developed a model environment that mimics protein fibers. First they stamped stripes of a protein called fibronectin on glass plates, making sure to represent various widths. Then they deposited the cells—alternately hundreds of breast cancer cells and hundreds of normal cells—on these fiber­like stripes and used a microscope with time-lapse capabilties to observe and quantify their behavior.

On fibers that were 6 or 9 microns wide—the typical size of fibers in tumors—half the breast cancer cells elongated and slid around the cells they collided with. Conversely, 99% of the normal breast cells did an about face.

To under­stand what gave the cancer cells this remarkable agility, the Northeastern researchers, led by Anand Asthagiri, explored the influence of fiber widths and genetic perturbations. They presented their results April 26 in the Biophysical Journal, in an article entitled, “Regulators of Metastasis Modulate the Migratory Response to Cell Contact under Spatial Confinement.”

“Downregulating the cell–cell adhesion protein, E-cadherin, enables MCF-10A cells to slide on narrower micropatterns; meanwhile, introducing exogenous E-cadherin in metastatic MDA-MB–231 cells increases the micropattern dimension at which they slide,” wrote the article’s authors.

This finding led the Northeastern team to consider the characteristic fibrillar dimension (CFD) at which effective sliding is achieved as a metric of sliding ability under spatial confinement.

“Using this metric, we show that metastasis-promoting genetic perturbations enhance cell sliding and reduce CFD,” the article’s authors continued. “Activation of ErbB2 combined with downregulation of the tumor suppressor and cell polarity regulator, PARD3, reduced the CFD, in agreement with their cooperative role in inducing metastasis in vivo. The CFD was further reduced by a combination of ErbB2 activation and transforming growth factor β stimulation, which is known to enhance invasive behavior.”

Asthagiri’s system is relatively easy to construct and suited for rapid imaging—two qualities that make it an excellent candidate for screening new cancer drugs. Pharmaceutical companies could input the drugs along with the cancer cells and mea­sure how effectively they inhibit sliding.

In the future, the system could also alert cancer patients and clinicians before metastasis starts. Studies with patients have shown that the structure of a tumor’s protein-fiber scaffolding can indicate how far the disease has progressed. The researchers found that certain aggressive genetic mutations enabled cells to slide on very narrow fibers, whereas cells with milder mutations would slide only when the fibers got much wider. Clinicians could biopsy the tumor and mea­sure the width of the fibers to see if that danger point were approaching. “We can start to say, ‘If these fibers are approaching X microns wide, it’s urgent that we hit certain path­ways with drugs,” said Asthagiri.

Questions, of course, remain. Do other types of cancer cells also have the ability to slide? What additional genes play a role?

Next steps, says Asthagiri, include expanding their fiber­like stripes into three-dimensional models that more closely represent the fibers in actual tumors and testing cancer and normal cells together. “There are so many types of cells in a tumor environment—immune cells, blood cells, and so on,” he noted. “We want to better emulate what’s hap­pening in the body rather than in isolated cells interacting on a platform.”

 

Regulators of Metastasis Modulate the Migratory Response to Cell Contact under Spatial Confinement.

The breast tumor microenvironment (TMEN) is a unique niche where protein fibers help to promote invasion and metastasis. Cells migrating along these fibers are constantly interacting with each other. How cells respond to these interactions has important implications. Cancer cells that circumnavigate or slide around other cells on protein fibers take a less tortuous path out of the primary tumor; conversely, cells that turn back upon encountering other cells invade less efficiently. The contact response of migrating cancer cells in a fibrillar TMEN is poorly understood. Here, using high-aspect ratio micropatterns as a model fibrillar platform, we show that metastatic cells overcome spatial constraints to slide effectively on narrow fiber-like dimensions, whereas nontransformed MCF-10A mammary epithelial cells require much wider micropatterns to achieve moderate levels of sliding. Downregulating the cell-cell adhesion protein, E-cadherin, enables MCF-10A cells to slide on narrower micropatterns; meanwhile, introducing exogenous E-cadherin in metastatic MDA-MB-231 cells increases the micropattern dimension at which they slide. We propose the characteristic fibrillar dimension (CFD) at which effective sliding is achieved as a metric of sliding ability under spatial confinement. Using this metric, we show that metastasis-promoting genetic perturbations enhance cell sliding and reduce CFD. Activation of ErbB2 combined with downregulation of the tumor suppressor and cell polarity regulator, PARD3, reduced the CFD, in agreement with their cooperative role in inducing metastasis in vivo. The CFD was further reduced by a combination of ErbB2 activation and transforming growth factor β stimulation, which is known to enhance invasive behavior. These findings demonstrate that sliding is a quantitative property and a decrease in CFD is an effective metric to understand how multiple genetic hits interact to change cell behavior in fibrillar environments. This quantitative framework sheds insights into how genetic perturbations conspire with fibrillar maturation in the TMEN to drive the invasive behavior of cancer cells.

sjwilliamspa

There was a nice paper a few years ago by Dr. Edna Cukerman from Fox Chase showing how tumor cells slid down on fiber tracks generated from tumor stromal cells and how this pattern of movement is not as random as one would think. if extracellular matrix was generated from normal stromal cells you would not find athis type of coordinated movement.

 

 

Fatty acid oxidation disruption: a therapeutic alternative for triple negative breast cancer

Hormone therapy is ineffective against triple negative breast cancers (TNBC) as they lack HER2, Estrogen, and Progesterone receptors. Therefore new targetable pathways are needed to halt the cancer’s progression. Researchers at UCSF have outlined a means of treating TNBC through disruption of fatty acid oxidation (FAO). The pathway was first revealed as a potential target through metabolomics and gene signatures, identifying upregulated FAO intermediates in MYC-overexpressing TNBC samples. Considering the location, in the proximity of adipose-rich mammary glands, breast cancer FAO dependence pathway seemed to be a logical pathway. Subsequent inhibition of FAO with etomixir , an inhibitor of a major enzyme carnitine palmitoyltransferase 1 (CPT1) in the FAO pathway, lead to dramatic decreases in ATP production in MYC-overexpressing cell lines. Although a decrease in proliferation of cells in culture was observed viability remained unchanged. However, further testing of etomixir in vivo within patient derived xenograft models increased success of FAO disruption with a 4 to 6-fold decrease in relative tumor volume. The differential performance between in vitro and in vivo treatments indicates a need to recapitulate the actual tumor environment when studying metabolic manipulation regimens.

Camarda, et. al. Inhibition of fatty acid oxidation as a therapy for MYC-overexpressing triple-negative breast cancer.  Nature Medicine   

Inhibition of fatty acid oxidation as a therapy for MYC-overexpressing triple-negative breast cancer

Roman CamardaAlicia Y ZhouRebecca A Kohnz,….,Daniel K Nomura & Andrei Goga
Nature Medicine22,427–432(2016)
       
              http://dx.doi.org:/10.1038/nm.4055

Expression of the oncogenic transcription factor MYC is disproportionately elevated in triple-negative breast cancer (TNBC), as compared to estrogen receptor–, progesterone receptor– or human epidermal growth factor 2 receptor–positive (RP) breast cancer1, 2. We and others have shown that MYC alters metabolism during tumorigenesis3, 4. However, the role of MYC in TNBC metabolism remains mostly unexplored. We hypothesized that MYC-dependent metabolic dysregulation is essential for the growth of MYC-overexpressing TNBC cells and may identify new therapeutic targets for this clinically challenging subset of breast cancer. Using a targeted metabolomics approach, we identified fatty acid oxidation (FAO) intermediates as being dramatically upregulated in a MYC-driven model of TNBC. We also identified a lipid metabolism gene signature in patients with TNBC that were identified from The Cancer Genome Atlas database and from multiple other clinical data sets, implicating FAO as a dysregulated pathway that is critical for TNBC cell metabolism. We found that pharmacologic inhibition of FAO catastrophically decreased energy metabolism in MYC-overexpressing TNBC cells and blocked tumor growth in a MYC-driven transgenic TNBC model and in a MYC-overexpressing TNBC patient–derived xenograft. These findings demonstrate that MYC-overexpressing TNBC shows an increased bioenergetic reliance on FAO and identify the inhibition of FAO as a potential therapeutic strategy for this subset of breast cancer.

 

3 Dimensional Ex-Vivo for In-situ Tumor Growth

Brain tumors are both difficult to treat and hard to study because of the organ they affect. The structure of the brain is extremely sensitive to alterations. Until recently the study of architectural alterations and their effects was mostly restricted to in vivo experiments. Typical culturing of brain tissue requires disaggregation and manipulation into a 2-dimensional format, losing any anatomically relevant structure. To study the in situ brain structure, a new technique has been described by researchers from the University of Erlangen-Nürnberg. By carefully sectioning the brains of 4 day-old mice and placing them on a 0.4 uM pore-size transwell membrane 6 well plate insert within required culture medium, they were able to study the endogenous structure under varying conditions. They injected astrocytes or glioma cells with a micropipette into the slices, and investigated the structural changes brain tumors effect in their environment. Termed the Vascular Organotypic Glioma Impact Model (VOGIM), it revealed all the characteristic pathological alterations normally associated with the disease in vivo such as tumor size and borders, vessel length, vessel junctions, and vessel branches, microglia, cell survival, and neuronal modifications. As this method allows for live cell fluorescent observation, they employed the technique to observe cultures treated with the chemotherapeutic Temozolamide (TMZ, Temodal/Temcad®). Indeed they found reduced tumor growth in treatment groups vs controls, but also revealed surprising reduction in microglial cells in the peritumoral region. Additionally, they were able to observe the lack of response TMZ elicited from microglial in healthy regions of the tissue, despite its overall reduction in vascularization towards normal levels. The VOGIM technique allows for ex vivo study of brain tissue requiring three dimensional measurements, but may also be extended to other tissues with unique morphology such as kidney, liver, and intestine.

Ghoochani, et al. (December, 2015) A versatile ex vivo technique for assaying tumor angiogenesis and microglia in the brain ONCOTARGET

 

A versatile ex vivo technique for assaying tumor angiogenesis and microglia in the brain

Ali Ghoochani1, Eduard Yakubov1, Tina Sehm1, Zheng Fan1, Stefan Hock1, Michael Buchfelder1, Ilker Y. Eyüpoglu1,*, Nicolai Savaskan1,*
http://dx.doi.org:/10.18632/oncotarget.6550      PDF |  HTML

Primary brain tumors are hallmarked for their destructive activity on the microenvironment and vasculature. However, solely few experimental techniques exist to access the tumor microenvironment under anatomical intact conditions with remaining cellular and extracellular composition. Here, we detail an ex vivo vascular glioma impact method (VOGIM) to investigate the influence of gliomas and chemotherapeutics on the tumor microenvironment and angiogenesis under conditions that closely resemble the in vivo situation. We generated organotypic brain slice cultures from rats and transgenic mice and implanted glioma cells expressing fluorescent reporter proteins. In the VOGIM, tumor-induced vessels presented the whole range of vascular pathologies and tumor zones as found in human primary brain tumor specimens. In contrast, non-transformed cells such as primary astrocytes do not alter the vessel architecture. Vascular characteristics with vessel branching, junctions and vessel length are quantitatively assessable as well as the peritumoral zone. In particular, the VOGIM resembles the brain tumor microenvironment with alterations of neurons, microglia and cell survival. Hence, this method allows live cell monitoring of virtually any fluorescence-reporter expressing cell. We further analyzed the vasculature and microglia under the influence of tumor cells and chemotherapeutics such as Temozolamide (Temodal/Temcad®). Noteworthy, temozolomide normalized vasculare junctions and branches as well as microglial distribution in tumor-implanted brains. Moreover, VOGIM can be facilitated for implementing the 3Rs in experimentations. In summary, the VOGIM represents a versatile and robust technique which allows the assessment of the brain tumor microenvironment with parameters such as angiogenesis, neuronal cell death and microglial activity at the morphological and quantitative level.

 

 

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Chemotherapy Benefit in Early Breast Cancer Patients

Larry H Bernstein, MD, FCAP, Curator

LPBI

 

Agendia’s MammaPrint® First and Only Genomic Assay to Receive Level 1A Clinical Utility Evidence for Chemotherapy Benefit in Early Breast Cancer Patients

http://www.b3cnewswire.com/201604191373/agendias-mammaprintr-first-and-only-genomic-assay-to-receive-level-1a-clinical-utility-evidence-for-chemotherapy-benefit-in-early-breast-cancer-patients.

  • Clinical high-risk patients with a low-risk MammaPrint® result, including 48 percent node-positive, had five-year distant metastasis-free survival rate in excess of 94 percent, whether randomized to receive adjuvant chemotherapy or not
  • MammaPrint could change clinical practice by substantially de-escalating the use of adjuvant chemotherapy and sparing many patients an aggressive treatment they will not benefit from
  • Forty-six percent overall reduction in chemotherapy prescription among clinically high-risk patients

April 19, 2016 / B3C newswire / Agendia, Inc., together with the European Organisation for Research and Treatment of Cancer (EORTC) and Breast International Group (BIG), announced results from the initial analysis of the primary objective of the Microarray In Node-negative (and 1 to 3 positive lymph node) Disease may Avoid ChemoTherapy (MINDACT) study at the American Association for Cancer Research Annual Meeting 2016 in New Orleans, LA.

Using the company’s MammaPrint® assay, patients with early-stage breast cancer who were considered at high risk for disease recurrence based on clinical and biological criteria had a distant metastasis-free survival at five years in excess of 94 percent.The MammaPrint test—the first and only genomic assay with FDA 510(k) clearance for use in risk assessment for women of all ages with early stage breast cancer—identified a large group of patients for whom five-year distant metastasis–free survival was equally good whether or not they received adjuvant chemotherapy (chemotherapy given post-surgery).

“The MINDACT trial design is the optimal way to prove clinical utility of a genomic assay,” said Prof. Laura van ’t Veer, CRO at Agendia, Leader, Breast Oncology Program, and Director, Applied Genomics at UCSF Helen Diller Family Comprehensive Cancer Center. “It gives the level 1A clinical evidence (prospective, randomized and controlled) that empowers physicians to clearly and confidently know when chemotherapy is part of optimal early-stage breast cancer therapy.  In this trial, MammaPrint (70-gene assay) was compared to the standard of care physicians use today, to decide what is the best treatment option for an early-stage breast cancer patient.”

The MINDACT trial is the first prospective randomized controlled clinical trial of a breast cancer recurrence genomic assay with level 1A clinical evidence and the first prospective translational research study of this magnitude in breast cancer to report the results of its primary objective.

Among the 3,356 patients enrolled in the MINDACT trial, who were categorized as having a high risk of breast cancer recurrence based on common clinical and pathological criteria (C-high), the MammaPrint assay reduced the chemotherapy treatment prescription by 46 percent.Using the 70-gene assay, MammaPrint, 48 percent of lymph-node positive breast cancer patients considered clinically high-risk (Clinical-high) and genomic low-risk (MammaPrint-low) had an excellent distant metastasis-free survival at five years in excess of 94 percent.

“Traditionally, physicians have relied on clinical-pathological factors such as age, tumor size, tumor grade, lymph node involvement, and hormone receptor status to make breast cancer treatment decisions,” said Massimo Cristofanilli, MD, Associate Director of Translational Research and Precision Medicine at the Robert H. Lurie Comprehensive Cancer Center, Northwestern University in Chicago. “These findings provide level 1A clinical utility evidence by demonstrating that the detection of low-risk of distant recurrence reported by the MammaPrint test can be safely used in the management of thousands of women by identifying those who can be spared from a toxic and unnecessary treatment.”

MINDACT is a randomized phase III trial that investigates the clinical utility of MammaPrint, when compared (or – “used in conjunction with”) to the standard clinical pathological criteria, for the selection of patients unlikely to benefit from adjuvant chemotherapy. From 2007 to 2011, 6,693 women who had undergone surgery for early-stage breast cancer enrolled in the trial (111 centers in nine countries). Participants were categorized as low or high risk for tumor recurrence in two ways: first, through analysis of tumor tissue using MammaPrint at a central location in Amsterdam; and second, using Adjuvant! Online, a tool that calculates risk of breast cancer recurrence based on common clinical and biological criteria.

Patients characterized in both clinical and genomic assessments as “low- risk” are spared chemotherapy, while patients characterized as “high- risk” are advised chemotherapy. Those with conflicting results are randomized to use either clinical or genomic risk (MammaPrint) evaluation to decide on chemotherapy treatment.

The MINDACT trial is managed and sponsored by the EORTC as part of an extensive and complex partnership in collaboration with Agendia and BIG, and many other academic and commercial partners, as well as patient advocates.

“These MINDACT trial results are a testament that the science of the MammaPrint test is the most robust in the genomic breast recurrence assay market.  Agendia will continue to collaborate with pharmaceutical companies, leading cancer centers and academic groups on additional clinical research and in the pursuit of bringing more effective, individualized treatments within reach of cancer patients,” said Mark Straley, Chief Executive Officer at Agendia. “We value the partnership with the EORTC and BIG and it’s a great honor to share this critical milestone.”

Breast cancer is the most frequently diagnosed cancer in women worldwide(1). In 2012, there were nearly 1.7 million new breast cancer cases among women worldwide, accounting for 25 percent of all new cancer cases in women(2).

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Protein profiling in cancer and metabolic diseases

Larry H. Bernstein, MD, FCAP, Curator

LPBI

 

Deep Protein Profiling Key

Company has encouraged by two recent reports that emphasise the importance of protein profiling to improve outcomes in cancer treatment.

http://www.technologynetworks.com/Proteomics/news.aspx?ID=190145

Proteome Sciences plc has strongly encouraged by two recent reports that emphasise the importance of protein profiling to improve outcomes in cancer treatment. These highlight the growing need for more detailed, personal assessment of protein profiles to improve the management of cancer treatment.

In the first study two groups from University College London and Cancer Research UK demonstrated that genetic mutations in cancer can lead to changes in the proteins on the cell surface1. These are new sequences which are seen as foreign by the body’s immune system and, with appropriate immunotherapy, the level of response in lung cancer was greatly enhanced.

However many of the patients with these types of mutations unfortunately still did not respond which highlighted the need for deeper analysis of the protein expression in tumours in order to better appreciate the mechanisms that contribute to treatment failure.

The second study, led by Professor Nigel Bundred of Manchester University, reported that use of two drugs that act on the same breast cancer target, an over-expressing protein called Her-2, were able to eradicate detectable tumours in around 10% of those treated in just 11 days, with 87% of those treated having a proteomic change indicating cells had stopped growing and/or cell death had increased2.

Whilst these results appear very promising it is worth noting that the over-expressing Her-2 target is only present in about 20% of breast tumours meaning this combination therapy was successful in clearing tumours in just 2% of the total breast cancer population.

Dr. Ian Pike, Chief Operating Officer of Proteome Sciences commented, “Both these recent studies should rightly be recognised as important steps forward towards better cancer treatment. However, in order to overcome the limitations of current drug therapy programs, a much deeper and more comprehensive analysis of the complex protein networks that regulate tumour growth and survival is required and will be essential to achieve a major advance in the battle to treat cancer.

“Our SysQuant® workflows provide that solution. As an example, in pancreatic cancer3 we have successfully mapped the complex network of regulatory processes and demonstrate the ability to devise personalised treatment combinations on an individual basis for each patient. A retrospective study with SysQuant® to predict response to the targeted drug Sorafenib in liver cancer is in process and we are planning further prospective trials to guide personalised treatment selection in liver cancer.

“We are already delivering systems-wide biology solutions through SysQuant® and TMTcalibrator™ programs to our clients that are generating novel biological data and results using more sensitive profiling that are helping them to better understand their drug development programs and to provide new biomarkers for tracking patient response in clinical trials.

“We are strongly positioned to deliver more comprehensive analysis of proteins and cellular pathways across other areas of disease and in particular to extend the use of SysQuant® with other leading cancer research groups in liver and other cancers.”

Proteome Sciences has also expanded its offering in personalised medicine through the use of its TMTcalibrator™ technology to uniquely identify protein biomarkers that reveal active cancer and other disease processes in body fluid samples. The importance of these ‘mechanistic’ biomarkers is that they are essential to monitor that drugs are being effective and that they can be used as early biomarkers of disease recurrence.

Using SysQuant® and TMTcalibrator™, Proteome Sciences can deliver more comprehensive analysis and provide unparalleled levels of sensitivity and breadth of coverage of the proteome, enabling faster, more efficient drug development and more accurate disease diagnosis.

 

Discovering ‘Outlier’ Enzymes

Researchers at TSRI and Salk Institute have discovered ‘Outlier’ enzymes that could offer new targets to treat type 2 diabetes and inflammatory disorders.

A team led by scientists at The Scripps Research Institute (TSRI) and the Salk Institute for Biological Studies have discovered two enzymes that appear to play a role in metabolism and inflammation—and might someday be targeted with drugs to treat type 2 diabetes and inflammatory disorders. The discovery is unusual because the enzymes do not bear a resemblance—in their structures or amino-acid sequences—to any known class of enzymes.

The team of scientists nevertheless identified them as “outlier” members of the serine/threonine hydrolase class, using newer techniques that detect biochemical activity. “A huge fraction of the human ‘proteome’ remains uncharacterized, and this paper shows how chemical approaches can be used to uncover proteins of a given functionality that have eluded classification based on sequence or predicted structure,” said co-senior author Benjamin F. Cravatt, chair of TSRI’s Department of Chemical Physiology.

“In this study, we found two genes that control levels of lipids with anti-diabetic and anti-inflammatory activity, suggesting exciting targets for diabetes and inflammatory diseases,” said co-senior author Alan Saghatelian, who holds the Dr. Frederik Paulsen Chair at the Salk Institute. The study, which appeared as a Nature Chemical Biology Advance Online Publication on March 28, 2016, began as an effort in the Cravatt laboratory to discover and characterize new serine/threonine hydrolases using fluorophosphonate (FP) probes—molecules that selectively bind and, in effect, label the active sites of these enzymes.

Pulling FP-binding proteins out of the entire proteome of test cells and identifying them using mass spectrometry techniques, the team matched nearly all to known hydrolases. The major outlier was a protein called androgen-induced gene 1 protein (AIG1). The only other one was a distant cousin in terms of sequence, a protein called ADTRP. “Neither of these proteins had been characterized as an enzyme; in fact, there had been little functional characterization of them at all,” said William H. Parsons, a research associate in the Cravatt laboratory who was co-first author of the study.

Experiments on AIG1 and ADTRP revealed that they do their enzymatic work in a unique way. “It looks like they have an active site that is novel—it had never been described in the literature,” said Parsons. Initial tests with panels of different enzyme inhibitors showed that AIG1 and ADTRP are moderately inhibited by inhibitors of lipases—enzymes that break down fats and other lipids. But on what specific lipids do these newly discovered outlier enzymes normally work?

At the Salk Institute, the Saghatelian laboratory was investigating a class of lipids it had discovered in 2014. Known as fatty acid esters of hydroxy fatty acids (FAHFAs), these molecules showed strong therapeutic potential. Saghatelian and his colleagues had found that boosting the levels of one key FAHFA lipid normalizes glucose levels in diabetic mice and also reduces inflammation.

“[Ben Cravatt’s] lab was screening panels of lipids to find the ones that their new enzymes work on,” said Saghatelian, who is a former research associate in the Cravatt laboratory. “We suggested they throw FAHFAs in there—and these turned out to be very good substrates.” The Cravatt laboratory soon developed powerful inhibitors of the newly discovered enzymes, and the two labs began working together, using the inhibitors and genetic techniques to explore the enzymes’ functions in vitro and in cultured cells.

Co-first author Matthew J. Kolar, an MD-PhD student, performed most of the experiments in the Saghatelian lab. The team concluded that AIG1 and ADTRP, at least in the cell types tested, appear to work mainly to break down FAHFAs and not any other major class of lipid. In principle, inhibitors of AIG1 and ADTRP could be developed into FAHFA-boosting therapies.

“Our prediction,” said Saghatelian, “is that if FAHFAs do what we think they’re doing, then using an enzyme inhibitor to block their degradation would make FAHFA levels go up and should thus reduce inflammation as well as improve glucose levels and insulin sensitivity.” The two labs are now collaborating on further studies of the new enzymes—and the potential benefits of inhibiting them—in mouse models of diabetes, inflammation and autoimmune disease.

“One of the neat things this study shows,” said Cravatt, “is that even for enzyme classes as well studied as the hydrolases, there may still be hidden members that, presumably by convergent evolution, arrived at that basic enzyme mechanism despite sharing no sequence or structural homology.”

Other co-authors of the study, “AIG1 and ADTRP are atypical integral membrane hydrolases that degrade bioactive FAHFAs,” were Siddhesh S. Kamat, Armand B. Cognetta III, Jonathan J. Hulce and Enrique Saez, of TSRI; and co-senior author Barbara B. Kahn of Beth Israel Deaconess Medical Center and Harvard Medical School

 

New Weapon Against Breast Cancer

Molecular marker in healthy tissue can predict a woman’s risk of getting the disease, research says.

Harvard Stem Cell Institute (HSCI) researchers at Dana-Farber Cancer Institute (DFCI) and collaborators at Brigham and Women’s Hospital (BWH) have identified a molecular marker in normal breast tissue that can predict a woman’s risk for developing breast cancer, the leading cause of death in women with cancer worldwide.

The work, led by HSCI principal faculty member Kornelia Polyak and Rulla Tamimi of BWH, was published in an early online release and in the April 1 issue of Cancer Research.

The study builds on Polyak’s earlier research finding that women already identified as having a high risk of developing cancer — namely those with a mutation called BRCA1 or BRCA2 — or women who did not give birth before their 30s had a higher number of mammary gland progenitor cells.

In the latest study, Polyak, Tamimi, and their colleagues examined biopsies, some taken as many as four decades ago, from 302 participants in the Nurses’ Health Study and the Nurses’ Health Study II who had been diagnosed with benign breast disease. The researchers compared tissue from the 69 women who later developed cancer to the tissue from the 233 women who did not. They found that women were five times as likely to develop cancer if they had a higher percentage of Ki67, a molecular marker that identifies proliferating cells, in the cells that line the mammary ducts and milk-producing lobules. These cells, called the mammary epithelium, undergo drastic changes throughout a woman’s life, and the majority of breast cancers originate in these tissues.

Doctors already test breast tumors for Ki67 levels, which can inform decisions about treatment, but this is the first time scientists have been able to link Ki67 to precancerous tissue and use it as a predictive tool.

“Instead of only telling women that they don’t have cancer, we could test the biopsies and tell women if they were at high risk or low risk for developing breast cancer in the future,” said Polyak, a breast cancer researcher at Dana-Farber and co-senior author of the paper.

“Currently, we are not able to do a very good job at distinguishing women at high and low risk of breast cancer,” added co-senior author Tamimi, an associate professor at the Harvard T.H. Chan School of Public Health and Harvard Medical School. “By identifying women at high risk of breast cancer, we can better develop individualized screening and also target risk reducing strategies.”

To date, mammograms are the best tool for the early detection, but there are risks associated with screening. False positive and negative results and over-diagnosis could cause psychological distress, delay treatment, or lead to overtreatment, according to the National Cancer Institute (NCI).

Mammography machines also use low doses of radiation. While a single mammogram is unlikely to cause harm, repeated screening can potentially cause cancer, though the NCI writes that the benefits “nearly always outweigh the risks.”

“If we can minimize unnecessary radiation for women at low risk, that would be good,” said Tamimi.

Screening for Ki67 levels would “be easy to apply in the current setting,” said Polyak, though the researchers first want to reproduce the results in an independent cohort of women.

 

AIG1 and ADTRP are atypical integral membrane hydrolases that degrade bioactive FAHFAs

William H ParsonsMatthew J Kolar, …., Barbara B KahnAlan Saghatelian & Benjamin F Cravatt

Nature Chemical Biology 28 March 2016                    http://dx.doi.org:/10.1038/nchembio.2051

Enzyme classes may contain outlier members that share mechanistic, but not sequence or structural, relatedness with more common representatives. The functional annotation of such exceptional proteins can be challenging. Here, we use activity-based profiling to discover that the poorly characterized multipass transmembrane proteins AIG1 and ADTRP are atypical hydrolytic enzymes that depend on conserved threonine and histidine residues for catalysis. Both AIG1 and ADTRP hydrolyze bioactive fatty acid esters of hydroxy fatty acids (FAHFAs) but not other major classes of lipids. We identify multiple cell-active, covalent inhibitors of AIG1 and show that these agents block FAHFA hydrolysis in mammalian cells. These results indicate that AIG1 and ADTRP are founding members of an evolutionarily conserved class of transmembrane threonine hydrolases involved in bioactive lipid metabolism. More generally, our findings demonstrate how chemical proteomics can excavate potential cases of convergent or parallel protein evolution that defy conventional sequence- and structure-based predictions.

Figure 1: Discovery and characterization of AIG1 and ADTRP as FP-reactive proteins in the human proteome.

 

http://www.nature.com/nchembio/journal/vaop/ncurrent/carousel/nchembio.2051-F1.jpg

(a) Competitive ABPP-SILAC analysis to identify FP-alkyne-inhibited proteins, in which protein enrichment and inhibition were measured in proteomic lysates from SKOV3 cells treated with FP-alkyne (20 μM, 1 h) or DMSO using the FP-biotin…

 

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  5. Simon, G.M. & Cravatt, B.F. Activity-based proteomics of enzyme superfamilies: serine hydrolases as a case study. J. Biol. Chem. 285, 1105111055 (2010).
  6. Bachovchin, D.A. et al. Superfamily-wide portrait of serine hydrolase inhibition achieved by library-versus-library screening. Proc. Natl. Acad. Sci. USA 107, 2094120946 (2010).
  7. Jessani, N. et al. A streamlined platform for high-content functional proteomics of primary human specimens. Nat. Methods 2, 691697 (2005).
  8. Higa, H.H., Diaz, S. & Varki, A. Biochemical and genetic evidence for distinct membrane-bound and cytosolic sialic acid O-acetyl-esterases: serine-active-site enzymes. Biochem. Biophys. Res. Commun. 144, 10991108 (1987).

Academic cross-fertilization by public screening yields a remarkable class of protein phosphatase methylesteras-1 inhibitors

Proc Natl Acad Sci U S A. 2011 Apr 26; 108(17): 6811–6816.    doi:  10.1073/pnas.1015248108
National Institutes of Health (NIH)-sponsored screening centers provide academic researchers with a special opportunity to pursue small-molecule probes for protein targets that are outside the current interest of, or beyond the standard technologies employed by, the pharmaceutical industry. Here, we describe the outcome of an inhibitor screen for one such target, the enzyme protein phosphatase methylesterase-1 (PME-1), which regulates the methylesterification state of protein phosphatase 2A (PP2A) and is implicated in cancer and neurodegeneration. Inhibitors of PME-1 have not yet been described, which we attribute, at least in part, to a dearth of substrate assays compatible with high-throughput screening. We show that PME-1 is assayable by fluorescence polarization-activity-based protein profiling (fluopol-ABPP) and use this platform to screen the 300,000+ member NIH small-molecule library. This screen identified an unusual class of compounds, the aza-β-lactams (ABLs), as potent (IC50 values of approximately 10 nM), covalent PME-1 inhibitors. Interestingly, ABLs did not derive from a commercial vendor but rather an academic contribution to the public library. We show using competitive-ABPP that ABLs are exquisitely selective for PME-1 in living cells and mice, where enzyme inactivation leads to substantial reductions in demethylated PP2A. In summary, we have combined advanced synthetic and chemoproteomic methods to discover a class of ABL inhibitors that can be used to selectively perturb PME-1 activity in diverse biological systems. More generally, these results illustrate how public screening centers can serve as hubs to create spontaneous collaborative opportunities between synthetic chemistry and chemical biology labs interested in creating first-in-class pharmacological probes for challenging protein targets.

Protein phosphorylation is a pervasive and dynamic posttranslational protein modification in eukaryotic cells. In mammals, more than 500 protein kinases catalyze the phosphorylation of serine, threonine, and tyrosine residues on proteins (1). A much more limited number of phosphatases are responsible for reversing these phosphorylation events (2). For instance, protein phosphatase 2A (PP2A) and PP1 are thought to be responsible together for > 90% of the total serine/threonine phosphatase activity in mammalian cells (3). Specificity is imparted on PP2A activity by multiple mechanisms, including dynamic interactions between the catalytic subunit (C) and different protein-binding partners (B subunits), as well as a variety of posttranslational chemical modifications (2, 4). Within the latter category is an unusual methylesterification event found at the C terminus of the catalytic subunit of PP2A that is introduced and removed by a specific methyltransferase (leucine carbxoylmethyltransferase-1 or LCMT1) (5, 6) and methylesterase (protein phosphatase methylesterase-1 or PME-1) (7), respectively (Fig. 1A). PP2A carboxymethylation (hereafter referred to as “methylation”) has been proposed to regulate PP2A activity, at least in part, by modulating the binding interaction of the C subunit with various regulatory B subunits (810). A predicted outcome of these shifts in subunit association is the targeting of PP2A to different protein substrates in cells. PME-1 has also been hypothesized to stabilize inactive forms of nuclear PP2A (11), and recent structural studies have shed light on the physical interactions between PME-1 and the PP2A holoenzyme (12).

There were several keys to the success of our probe development effort. First, screening for inhibitors of PME-1 benefited from the fluopol-ABPP technology, which circumvented the limited throughput of previously described substrate assays for this enzyme. Second, we were fortunate that the NIH compound library contained several members of the ABL class of small molecules. These chiral compounds, which represent an academic contribution to the NIH library, occupy an unusual portion of structural space that is poorly accessed by commercial compound collections. Although at the time of their original synthesis (23) it may not have been possible to predict whether these ABLs would show specific biological activity, their incorporation into the NIH library provided a forum for screening against many proteins and cellular targets, culminating in their identification as PME-1 inhibitors. We then used advanced chemoproteomic assays to confirm the remarkable selectivity displayed by ABLs for PME-1 across (and beyond) the serine hydrolase superfamily. That the mechanism for PME-1 inhibition involves acylation of the enzyme’s conserved serine nucleophile (Fig. 3) suggests that exploration of a more structurally diverse set of ABLs might uncover inhibitors for other serine hydrolases. In this way, the chemical information gained from a single high-throughput screen may be leveraged to initiate probe development programs for additional enzyme targets.

Projecting forward, this research provides an example of how public small-molecule screening centers can serve as a portal for spawning academic collaborations between chemical biology and synthetic chemistry labs. By continuing to develop versatile high-throughput screens and combining them with a small-molecule library of expanding structural diversity conferred by advanced synthetic methodologies, academic biologists and chemists are well-positioned to collaboratively deliver pharmacological probes for a wide range of proteins and pathways in cell biology.

 

New weapon against breast cancer

Molecular marker in healthy tissue can predict a woman’s risk of getting the disease, research says

April 6, 2016 | Popular
BRC_Cancer605

 

New Group of Aging-Related Proteins Discovered

http://www.genengnews.com/gen-news-highlights/new-group-of-aging-related-proteins-discovered/81252599/

Scientists have discovered a group of six proteins that may help to divulge secrets of how we age, potentially unlocking new insights into diabetes, Alzheimer’s, cancer, and other aging-related diseases.

The proteins appear to play several roles in our bodies’ cells, from decreasing the amount of damaging free radicals and controlling the rate at which cells die to boosting metabolism and helping tissues throughout the body respond better to insulin. The naturally occurring amounts of each protein decrease with age, leading investigators to believe that they play an important role in the aging process and the onset of diseases linked to older age.

The research team led by Pinchas Cohen, M.D., dean and professor of the University of Southern California Leonard Davis School of Gerontology, identified the proteins and observed their origin from mitochondria and their game-changing roles in metabolism and cell survival. This latest finding builds upon prior research by Dr. Cohen and his team that uncovered two significant proteins, humanin and MOTS-c, hormones that appear to have significant roles in metabolism and diseases of aging.

Unlike most other proteins, humanin and MOTS-c are encoded in mitochondria. Dr. Cohen’s team used computer analysis to see if the part of the mitochondrial genome that provides the code for humanin was coding for other proteins as well. The analysis uncovered the genes for six new proteins, which were dubbed small humanin-like peptides, or SHLPs, 1 through 6 (pronounced “schlep”).

After identifying the six SHLPs and successfully developing antibodies to test for several of them, the team examined both mouse tissues and human cells to determine their abundance in different organs as well as their functions. The proteins were distributed quite differently among organs, which suggests that the proteins have varying functions based on where they are in the body. Of particular interest is SHLP 2, according to Dr. Cohen.  The protein appears to have insulin-sensitizing, antidiabetic effects as well as neuroprotective activity that may emerge as a strategy to combat Alzheimer’s disease. He added that SHLP 6 is also intriguing, with a unique ability to promote cancer cell death and thus potentially target malignant diseases.

Proteins That May Protect Against Age Related Illnesses Discovered

 

The cell proliferation antigen Ki-67 organises heterochromatin

 Michal Sobecki, 

Antigen Ki-67 is a nuclear protein expressed in proliferating mammalian cells. It is widely used in cancer histopathology but its functions remain unclear. Here, we show that Ki-67 controls heterochromatin organisation. Altering Ki-67 expression levels did not significantly affect cell proliferation in vivo. Ki-67 mutant mice developed normally and cells lacking Ki-67 proliferated efficiently. Conversely, upregulation of Ki-67 expression in differentiated tissues did not prevent cell cycle arrest. Ki-67 interactors included proteins involved in nucleolar processes and chromatin regulators. Ki-67 depletion disrupted nucleologenesis but did not inhibit pre-rRNA processing. In contrast, it altered gene expression. Ki-67 silencing also had wide-ranging effects on chromatin organisation, disrupting heterochromatin compaction and long-range genomic interactions. Trimethylation of histone H3K9 and H4K20 was relocalised within the nucleus. Finally, overexpression of human or Xenopus Ki-67 induced ectopic heterochromatin formation. Altogether, our results suggest that Ki-67 expression in proliferating cells spatially organises heterochromatin, thereby controlling gene expression.

 

A protein called Ki-67 is only produced in actively dividing cells, where it is located in the nucleus – the structure that contains most of the cell’s DNA. Researchers often use Ki-67 as a marker to identify which cells are actively dividing in tissue samples from cancer patients, and previous studies indicated that Ki-67 is needed for cells to divide. However, the exact role of this protein was not clear. Before cells can divide they need to make large amounts of new proteins using molecular machines called ribosomes and it has been suggested that Ki-67 helps to produce ribosomes.

Now, Sobecki et al. used genetic techniques to study the role of Ki-67 in mice. The experiments show that Ki-67 is not required for cells to divide in the laboratory or to make ribosomes. Instead, Ki-67 alters the way that DNA is packaged in the nucleus. Loss of Ki-67 from mice cells resulted in DNA becoming less compact, which in turn altered the activity of genes in those cells.

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Prognostic biomarker for NSCLC and Cancer Metastasis

Larry H. Bernstein, MD, FCAP, Curator

LPBI

 

Membranous CD24 expression as detected by the monoclonal antibody SWA11 is a prognostic marker in non-small cell lung cancer patients

Michael MajoresAnne SchindlerAngela FuchsJohannes SteinLukas HeukampPeter Altevogt and Glen Kristiansen

BMC Clinical Pathology201515:19   http://dx.doi.org:/10.1186/s12907-015-0019-z

Background    Lung cancer is one of the most common malignant neoplasms worldwide and has a high mortality rate. To enable individualized therapy regimens, a better understanding of the molecular tumor biology has still to be elucidated. The expression of the cell surface protein CD24 has already been claimed to be associated with shorter patient survival in non-small cell lung cancer (NSCLC), however, the prognostic value and applicability of CD24 immunostaining in paraffin embedded tissue specimens has been questioned due to the recent acknowledgement of restricted epitope specificity of the commonly used antibody SN3b.   Methods    A cohort of 137 primary NSCLC cases was immunostained with a novel CD24 antibody (clone SWA11), which specifically recognizes the CD24 protein core and the resulting expression data were compared with expression profiles based on the monoclonal antibody SN3b. Furthermore, expression data were correlated to clinico-pathological parameters. Univariate and multivariate survival analyses were conducted with Kaplan Meier estimates and Cox regression, respectively. Results    CD24 positivity was found in 34 % resp. 21 % (SN3b) of NSCLC with a membranous and/or cytoplasmic staining pattern. Kaplan-Meier analyses revealed that membranous, but not cytoplasmic CD24 expression (clone SWA11) was associated with lympho-nodular spread and shorter overall survival times (both p < 0.05). CD24 expression established by SN3b antibodies did not reveal significant clinicopathological correlations with overall survival, neither for cytoplasmic nor membranous CD24 staining.  Conclusions    Membranous CD24 immunoreactivity, as detected with antibody clone SWA11 may serve as a prognostic factor for lymphonodular spread and poorer overall survival. Furthermore, these results corroborate the importance of a careful distinction between membranous and cytoplasmic localisation, if CD24 is to be considered as a potential prognostic biomarker.

 

Lung cancer is a major cause of carcinoma related death, being responsible for 17.8 % of all cancer deaths and accounting for more than a million deaths worldwide per year [1]. Despite intense studies to improve therapy options, its prognosis has remained poor with a 5-year overall survival rate of less than 15 % [2].

In the past decade, the largest subgroup of lung cancer, i.e. non-small cell lung cancer (NSCLC), has been subjected to exerted research for a better understanding of the underlying molecular biology of lung cancer. More than ten years ago, CD24 has already been suggested as a novel and promising biomarker for carcinoma progression in NSCLC [3] and several groups have confirmed this finding on protein and transcript level [2, 4]. CD24 is a highly glycosylated protein, that binds to the cell surface through a GPI (glycosyl-phosphatidylinositol)-anchor and functions as a cell adhesion molecule and is involved in cell-cell-interaction via its P-selectin binding site [5]. CD24 has been found to be expressed by pre-B-lymphocytes [5]. It is assumed that CD24-positive cells can attach more easily to platelets and activated endothelial cells [6, 7]. Notably, CD24 has also been observed in many human carcinomas, such as ovarian cancer, renal cell cancer, breast cancer and NSCLC [3, 812]. In epithelial ovarian cancer high scores of cytoplasmic CD24 were highly predictive of shorter patient survival times (mean 97.8 vs. 36.5 months), whereas membranous CD24 expression seemed to have no influence on survival times. Interestingly, CD24 positivity (membranous or cytoplasmic) of prostate cancer samples was significantly associated to younger patient age and higher pT stages and a higher 3-year prostate-specific antigen (PSA) relapse rate compared with CD24-negative tumours.

In patients with gallbladder carcinoma, tumors with up-regulation of CD24 revealed lymph node metastasis and lymphovascular invasion more frequently. Moreover, up-regulation of CD24 tended to show deeper invasion depth and higher TNM stage [13]. Together, these findings support CD24 as a prognostic marker for carcinoma progression and poorer survival.

Despite these intriguing findings, major concerns regarding a lack of epitope specificity of the commonly used monoclonal antibody SN3b have been raised [14]. Recent findings indicate that the mAb (monoclonal antibody) SN3b does not bind to the protein core itself, but binds to a glycan structure that decorates the CD24 molecule. On the one hand, this motif is not present on all forms of CD24 and—on the other hand—it can be present in other epitopes irrespective of CD24 [14]. These limitations underline the need for more specific CD24 antibodies, such as the mAb SWA11 antibody that has been suggested to be more specific as it binds to the protein core [14].

As CD24 is a promising biomarker for the risk assessment of disease progression, the goal of the present study was to investigate CD24 expression in NSCLC using the novel, more specific monoclonal antibody (mAb) SWA11. Special emphasis was put on the comparison of SN3b- and SWA11-mediated CD24 detection regarding a) the subcellular distribution of CD24 expression (i.e. membranous versus cytoplasmic expression) and b) its correlation with various clinicopathological features including patient survival times.

Table 1

Clinicopathological characteristics of the NSCLC cohort

  AC SCC
N (%) N (%)
Tumour stage (pT)
1 29 (21.2 %) 5 (3.6)
2 51 (37.2 %) 23 (16.8 %)
3 6 (4.4 %) 6 (4.4 %)
4 1 (0.7 %) 0 (0 %)
Nodal Status (pN) 0 37 (27.0 %) 15 (10.9 %)
1 15 (10.9 %) 9 (6.6 %)
2 14 (10.2 %) 3 (2.2 %)
3 1 (0.7 %) 0 (0.0 %)
Grading (G) 1 5 (3.6 %) 0 (0.0 %)
2 41 (29.9 %) 16 (11.6 %)
3 44 (32.1 %) 17 (12.4 %)
Mean age at surgery 64,2 64,56
(median age) (65) (67)
Sex (m:w) 68:34 30:5
Median OS (months) 52 24
(SD; 95 % CI [months]) (±23.7; 5.5– 98.5) (± 12.8;0.0– 49.0)

 

Immunohistochemical detection of CD24 expression using clone SWA11 and SN3b

Using the mAb SWA11, 47 of 137 (34.3 %) NSCLC revealed CD24 expression (either cytoplasmic or membranous) (Table 2). CD24 expression was observed more frequently in adenocarcinomas (AC) than in squamous cell carcinomas (SCC). In AC cytoplasmic expression was observed more frequently than membranous expression. In SCC, both cyptoplasmic and membranous expression was rare. Normal lung parenchyma (i.e. alveolar surface cells) showed no expression of CD24. Bronchial epithelium showed a strong membranous and cytoplasmic staining of the brush border (Fig. 1).

Table 2

Cytoplasmic and membranous expression of CD24

SWA11 (mAb clone) SN3b (mAB clone)
  AC SCC   AC SCC
Cytoplasmic N (%) N (%) Cytoplasmic N (%) N (%)
0 45 (32.6 %) 19 (13.8 %) 0 76 (55.1 %) 31 (22.5 %)
1 22 (15.9 %) 8 (5.8 %) 1 12 (8.7 %) 1 (0.7 %)
2 17 (12.3 %) 4 (2.9 %) 2 7 (5.1 %) 2 (1.4 %)
3 18 (13.0 %) 4 (2.9 %) 3 1 (0.7 %) 0 (0 %)
AC SCC AC SCC
Membranous N (%) N (%) Membranous N (%) N (%)
0 68 (49.3 %) 21 (15.2 %) 0 64 (46.4 %) 30 (21.7 %)
1 21 (15.2 %) 5 (3.6 %) 1 10 (7.2 %) 2 (1.4 %)
2 8 (5.8 %) 4 (2.9 %) 2 12 (8.7 %) 2 1.4 %)
3 5 (3.6 %) 5 (3.6 %) 3 10 (7.2 %) 0 (0 %)

Staining intensities are determined as follows:

0: negative or equivocal, 1: weak, 2: moderate and 3: strong CD24 staining

 

https://static-content.springer.com/image/art%3A10.1186%2Fs12907-015-0019-z/MediaObjects/12907_2015_19_Fig1_HTML.gif

Fig 1

The immunohistochemical characterization reveals membranous and/or cytoplasmic CD24 (mAb SWA11) expression. Strong cytoplasmic CD24 expression is found in a proportion of both AC (a) and SCC (b, d) specimens. Membranous CD24 expression can be pronounced with only scant or even absent cytoplasmic staining as shown in the AC (c). Also, both membranous and cytoplasmic CD24 detection can be found in some instances (d), the insert is showing the corresponding squamous carcinoma in-situ with membranous staining. Simultaneous membranous and cytoplasmic CD24 expression is also found in AC specimens (e, f). In normal tissue, alveolar epithelial cells do not express CD24 (g), whereas CD24 staining is found at the apical cell membrane of bronchial respiratory epithelia (h)

Using the mAb SN3b, 29 of 137 (21.2 %) NSCLC revealed CD24 expression (either cytoplasmic or membranous) (Table 2). As above, CD24 expression was observed more frequently in adenocarcinomas (AC) than in squamous cell carcinomas (SCC). However, in contrast to mAb SWA11 cytoplasmic expression was observed less frequently than membranous expression in AC. In SCC, both cytoplasmic and membranous expression was rare. Normal lung parenchyma (i.e. alveolar surface cells) showed a distinct membranous immunoreactivity. Bronchial epithelium revealed both membranous and cytoplasmic staining of CD24.

Correlation between SWA11 and SN3b: As SWA11 and SN3b detect different epitopes, we evaluated the correlation of the immunohistochemical staining patterns. Of 132 NSCLC specimens with matched expression data, only 9 specimens (6.8 %) revealed a concordant CD24 expression. Of these cases, 4 cases revealed a concordant cytoplasmic staining and another 5 cases revealed a concordant membranous CD24 expression. Statistically, no significant correlation between the two mAb could be observed (cc = −0.63, p = 0.470; Fisher’s exact test p = 0.665). The correlation of cytoplasmic and membranous expression (for each antibody) was as follows: cc = 0.475 (p < 0.05) for SWA11 (n = 108) and cc = 0.140 (p = 0.11) for SN3b (n = 103).

Survival analyses

Recent studies indicate that CD24 expression is associated with tumor progression and poorer survival rates. Therefore, we performed follow up analyses with a special emphasis on 1) the prognostic value of mAb SWA11 in dependence on subcellular staining characteristics and 2) the prognostic values of different clinicopathological parameters:

Prognostic value of CD24 in Kaplan Meier Analyses

Only membranous CD24 (SWA11) staining revealed significantly poorer survival rates (median overall survival 21 vs. 52 months; p = 0.005) as illustrated in Fig. 2. In contrast, cytoplasmic CD24 (SWA11) staining did not affect the survival rates (median OS 34 vs. 35 months; p = 0.884) (Table 3). When stratifying the cohort into SCC (n = 35) and AC (n = 102) in Kaplan Meier analyses, membranous CD24 (SWA11) expression did not affect patients’ survival, neither in SCC (p = 0.243) nor AC (p = 0.135) (Table 3), probably due to the small number of observations (Fisher exact test: p > 0.05). After stratification for AC subtypes, membranous CD24 expression (SWA11) showed a tendency towards an association with poorer survival in acinar subtype AC, but failed significance (p = 0.328).
https://static-content.springer.com/image/art%3A10.1186%2Fs12907-015-0019-z/MediaObjects/12907_2015_19_Fig2_HTML.gif

Fig 2

Survival analysis. Kaplan-Meier curves according to SWA11 expression. Cases with moderate to strong expression were bundled in a ‘high expression’ and cases with negative or weak expression in a ‘low expression’ group. Membranous expression of CD24 detected by SWA11 proved to be an independent marker for shorter survival times in NSCLC (p = 0.005)

Table 3

Univariate survival analysis

SWA11 No. of cases Mean survival time Median survival time p-value
(months +/− s.e.) (months +/− s.e.)
Mem CD24
Negative 76 84.833 +/− 10.395 52.000 +/− 27.030 0.005
Positive 16 27.925 +/− 6.379 21.000 +/− 4.000
Cyto CD24
Negative 66 75.209 +/− 10.577 35.000 +/− 12.422 0.884
Positive 26 60.540 +/− 11.551 34.000 +/− 12.196
Total CD24
Negative 64 76.972 +/− 10.841 35.000 +/− 13.726 0.633
Positive 28 57.535 +/− 10.895 34.000 +/− 9.303
SCC
Mem CD24 negative 16 52.063 +/− 14.668 16.000 +/− 16.000 0.243
Mem CD24 positive 7 21.571 +/− 7.201 24.000 +/− 23.568
AC
Mem CD24 negative 59 88.953 +/− 11.631 56.000 +/− 22.885 0.135
Mem CD24 positive 8 39.167 +/− 11.674 21.000 +/− 8.485
pN0 31 103.641 +/− 14.940 93.000 +/− 28.224 0.012
pN1+ 30 54.911 +/− 10.646 26.000 +/− 0.983

 

…..

Univariate survival analysis according to the Cox regression model (mAb SWA11)

  Beta HR (hazard ratio) 95 % CI of HR P-value
SWA11 mem all 0.856 2.353 1.268–4.364 0.007
pN 0.963 2.620 1.389–4.943 0.003
pT 0.844 2.325 1.279–4.224 0.006
Tumour type 0.975 2.651 1.999–3.517 0.000

Table 5

Multivariate survival analysis according to the Cox regression model (mAb SWA11)

  Beta HR (hazard ratio) 95 % CI of HR P-value
SWA11 mem all 0.944 2.571 1.211–5.458 0.014
pN 0.737 2.091 1.087–4.021 0.027
pT 0.587 1.799 0.755–4.283 0.185

 

…..

In the present study, we have analyzed immunohistochemical staining characteristics and the prognostic value of CD24 expression in NSCLC with a special emphasis on the comparison of the CD24 antibodies SWA11 and SN3b. The most important result of our study is that the prognostic relevance of CD24 is critically dependent on the careful consideration of sub-cellular compartments and the epitope specificity of the antibody used.

Overall, about one third of the NSCLC cohort revealed a significant CD24 expression (either cytoplasmic or membranous). These results are in line with the findings of other studies. In another NSCLC cohort, CD24 (SN3b) expression was found in 33 % of the samples (87 of 267 cases) [2]. Consistent with those results, we have found similar rates of high CD24 expression levels (35 % of the cases) for SWA11. Originally, we would have expected lower rates than those found by Lee et al, as they used the antibody SN3b, that also recognizes yet unidentified other glycoproteins next to CD24. Furthermore, they used whole mount sections instead of tissue microarrays. A possible explanation for rather equal detection rates would be the fact that it has been demonstrated that the epitope recognized by SN3b is indeed present in CD24, but is not found in all glycoforms of CD24 [14]. In contrast to the commonly used mAb SN3b, mAb SWA11 binds to the protein core of CD24 and does not depict other glycan moieties next to CD24. The protein core of CD24 is linear, consisting of the amino acid sequence leucine-proline-alanine (LAP) next to a glycosyl-phosphatidylinositol anchor [15].

CD24 expression has been associated with disease progression and cancer-related death in the majority of malignant tumors [2, 3, 16, 17], although a caveat to these data is that most of these studies are based on the supposedly less specific CD24 clone SN3b. Lee et al demonstrated a significant association between CD24-high expression (SN3b) and shorter patient survival times. Furthermore, Lee and colleagues and ourselves in former studies referred the results to cytoplasmic CD24 expression [2, 3].

Switching Off Cancers’ Ability to Spread

http://www.technologynetworks.com/rnai/news.aspx?ID=189704

A key molecule in breast and lung cancer cells can help switch off the cancers’ ability to spread around the body.

The findings by researchers at Imperial College London, published in the journal EMBO Reports, may help scientists develop treatments that prevent cancer travelling around the body – or produce some kind of test that allows doctors to gauge how likely a cancer is to spread. During tumour growth, cancer cells can break off and travel in the bloodstream or lymph system to other parts of the body, in a process called metastasis.

Patients whose cancers spread tend to have a worse prognosis, explains Professor Justin Stebbing, senior author of the study from the Department of Surgery and Cancer at Imperial: “The ability of a cancer to spread around the body has a large impact on a patient’s survival. However, at the moment we are still in the dark about why some cancers spread around the body – while others stay in one place. This study has given important insights into this process.”

The researchers were looking at breast and lung cancer cells and they found that a protein called MARK4 enables the cells to break free and move around to other parts of the body, such as the brain and liver. Although scientist are still unsure how it does this, one theory is it affects the cell’s internal scaffolding, enabling it to move more easily around the body. The team found that a molecule called miR-515-5p helps to silence, or switch off, the gene that produces MARK4.

In the study, the team used human breast cancer and lung cancer cells to show that the miR-515-5p molecule silences the gene MARK4. They then confirmed this in mouse models, which showed that increasing the amount of miR-515-5p prevents the spread of cancer cells. The findings also revealed that the silencer molecule was found in lower levels in human tumours that had spread around the body. The team then also established that patients with breast and lung cancers whose tumours had low amounts of these silencer molecules – or high amounts of MARK4 – had lower survival rates.

Researchers are now investigating whether either the MARK4 gene or the silencer molecule could be targeted with drugs. They are also investigating whether these molecules could be used to develop a test to indicate whether a patient’s cancer is likely to spread. Professor Stebbing said: “In our work we have shown that this silencer molecule is important in the spread of cancer. This is very early stage research, so we now need more studies to find out more about this molecule, and if it is present in other types of cancer.”

Dr Olivier Pardo, lead author of the paper, also from the Department of Surgery and Cancer at Imperial, added: “Our work also identified that MARK4 enables breast and lung cancer cells to both divide and invade other parts of the body. These findings could have profound implications for treating breast and lung cancers, two of the biggest cancer killers worldwide.” The study was supported by the NIHR Imperial Biomedical Research Centre, the Medical Research Council, Action Against Cancer and the Cancer Treatment and Research Trust.

 

‘Silencer molecules’ switch off cancer’s ability to spread around body

by Kate Wighton

main image

Scientists have revealed that a key molecule in breast and lung cancer cells can help switch off the cancers’ ability to spread around the body

The findings by researchers at Imperial College London, published in the journal EMBO Reports, may help scientists develop treatments that prevent cancer travelling around the body – or produce some kind of test that allows doctors to gauge how likely a cancer is to spread.

During tumour growth, cancer cells can break off and travel in the bloodstream or lymph system to other parts of the body, in a process called metastasis.

Patients whose cancers spread tend to have a worse prognosis, explains Professor Justin Stebbing, senior author of the study from the Department of Surgery and Cancer at Imperial: “The ability of a cancer to spread around the body has a large impact on a patient’s survival. However, at the moment we are still in the dark about why some cancers spread around the body – while others stay in one place. This study has given important insights into this process.”

The researchers were looking at breast and lung cancer cells and they found that a protein called MARK4 enables the cells to break free and move around to other parts of the body, such as the brain and liver. Although scientist are still unsure how it does this, one theory is it affects the cell’s internal scaffolding, enabling it to move more easily around the body.

 

miR‐515‐5p controls cancer cell migration through MARK4 regulation

Olivier E Pardo, Leandro Castellano, Catriona E Munro, Yili Hu, Francesco Mauri,Jonathan Krell, Romain Lara, Filipa G Pinho, Thameenah Choudhury, Adam EFrampton, Loredana Pellegrino, Dmitry Pshezhetskiy, Yulan Wang, JonathanWaxman, Michael J Seckl, Justin Stebbing    

EMBO reports http://embor.embopress.org/content/early/2016/02/10/embr.201540970     http://dx.doi.org:/
Here, we show that miR‐515‐5p inhibits cancer cell migration and metastasis. RNA‐seq analyses of both oestrogen receptor receptor‐positive and receptor‐negative breast cancer cells overexpressing miR‐515‐5p reveal down‐regulation of NRAS, FZD4, CDC42BPA, PIK3C2B and MARK4 mRNAs. We demonstrate that miR‐515‐5p inhibits MARK4 directly 3′ UTR interaction and that MARK4 knock‐down mimics the effect of miR‐515‐5p on breast and lung cancer cell migration. MARK4 overexpression rescues the inhibitory effects of miR‐515‐5p, suggesting miR‐515‐5p mediates this process through MARK4 down‐regulation. Furthermore, miR‐515‐5p expression is reduced in metastases compared to primary tumours derived from both in vivo xenografts and samples from patients with breast cancer. Conversely, miR‐515‐5p overexpression prevents tumour cell dissemination in a mouse metastatic model. Moreover, high miR‐515‐5p and low MARK4 expression correlate with increased breast and lung cancer patients’ survival, respectively. Taken together, these data demonstrate the importance of miR‐515‐5p/MARK4 regulation in cell migration and metastasis across two common cancers.
Embedded Image

miR‐515‐5p inhibits cancer progression, cell migration and metastasis through its direct target MARK4, a regulator of the cytoskeleton and cell motility. Moreover, reduced miR‐515‐5p and increased MARK4 levels in metastatic lung and breast cancer correlate with poor patient prognosis.

  • MARK4 down‐regulation promotes microtubule polymerisation.

  • Increased cell spreading downstream of miR‐515‐5p overexpression or MARK4 silencing hinders cell motility and invasiveness.

  • miR‐515‐5p overexpression or MARK4 silencing prevent organ colonisation by circulating tumour cells.

  • MARK4 inhibitors may represent novel therapeutic agents to control cancer dissemination.breasat cancer

 

Liquid Biopsy for NSCLC

http://www.technologynetworks.com/Diagnostics/news.aspx?ID=190276

‘Liquid biopsy’ blood test accurately detects key genetic mutations in most common form of lung cancer, study finds.

A simple blood test can rapidly and accurately detect mutations in two key genes in non-small cell lung tumors, researchers at Dana-Farber Cancer Institute and other institutions report in a new study – demonstrating the test’s potential as a clinical tool for identifying patients who can benefit from drugs targeting those mutations.

The test, known as a liquid biopsy, proved so reliable in the study that Dana-Farber/Brigham and Women’s Cancer Center (DF/BWCC) expects to offer it soon to all patients with non-small cell lung cancer (NSCLC), either at the time of first diagnosis or of relapse following previous treatment.

NSCLC is the most common form of lung cancer, diagnosed in more than 200,000 people in the United States each year, according to the American Cancer Society. An estimated 30 percent of NSCLC patients have mutations in either of the genes included in the study, and can often be treated with targeted therapies. The study is being published online today by the journal JAMA Oncology.

The liquid biopsy tested in the study – technically known as rapid plasma genotyping – involves taking a test tube-full of blood, which contains free-floating DNA from cancer cells, and analyzing that DNA for mutations or other abnormalities. (When tumor cells die, their DNA spills into the bloodstream, where it’s known as cell-free DNA.) The technique, which provides a “snapshot” of key genetic irregularities in a tumor, is a common tool in research for probing the molecular make-up of different kinds of cancers.

“We see plasma genotyping as having enormous potential as a clinical test, or assay – a rapid, noninvasive way of screening a cancer for common genetic fingerprints, while avoiding the challenges of traditional invasive biopsies,” said the senior author of the study, Geoffrey Oxnard, MD, thoracic oncologist and lung cancer researcher at Dana-Farber and Brigham and Women’s Hospital. “Our study was the first to demonstrate prospectively that a liquid biopsy technique can be a practical tool for making treatment decisions in cancer patients. The trial was such a success that we are transitioning the assay into a clinical test for lung cancer patients at DF/BWCC.”

The study involved 180 patients with NSCLC, 120 of whom were newly diagnosed, and 60 of whom had become resistant to a previous treatment, allowing the disease to recur. Participants’ cell-free DNA was tested for mutations in the EGFR and KRAS genes, and for a separate mutation in EGFR that allows tumor cells to become resistant to front-line targeted drugs. The test was performed with a technique known as droplet digital polymerase chain reaction (ddPCR), which counts the individual letters of the genetic code in cell-free DNA to determine if specific mutations are present. Each participant also underwent a conventional tissue biopsy to test for the same mutations. The results of the liquid biopsies were then compared to those of the tissue biopsies.

The data showed that liquid biopsies returned results much more quickly. The median turnaround time for liquid biopsies was three days, compared to 12 days for tissue biopsies in newly diagnosed patients and 27 days in drug-resistant patients.

Liquid biopsy was also found to be highly accurate. In newly diagnosed patients, the “predictive value” of plasma ddPCR was 100 percent for the primary EGFR mutation and the KRAS mutation – meaning that a patient who tested positive for either mutation was certain to have that mutation in his or her tumor. For patients with the EGFR resistance mutation, the predictive value of the ddPCR test was 79 percent, suggesting the blood test was able to find additional cases with the mutation that were missed using standard biopsies.

“In some patients with the EGFR resistance mutation, ddPCR detected mutations missed by standard tissue biopsy,” Oxnard remarked. “A resistant tumor is inherently made up of multiple subsets of cells, some of which carry different patterns of genetic mutations. A single biopsy is only analyzing a single part of the tumor, and may miss a mutation present elsewhere in the body. A liquid biopsy, in contrast, may better reflect the distribution of mutations in the tumor as a whole.”

When ddPCR failed to detect these mutations, the cause was less clear-cut, Oxnard says. It could indicate that the tumor cells don’t carry the mutations or, alternatively, that the tumor isn’t shedding its DNA into the bloodstream. This discrepancy between the test results and the presence of mutations was less common in patients whose cancer had metastasized to multiple sites in the body, researchers found.

The ddPCR-based test, or assay, was piloted and optimized for patients at the Translational Resarch lab of the Belfer Center for Applied Cancer Science at Dana-Farber. It was then validated for clinical use at Dana-Farber’s Lowe Center for Thoracic Oncology.

An advantage of this form of liquid biopsy is that it can help doctors quickly determine whether a patient is responding to therapy. Fifty participants in the study had repeat testing done after starting treatment for their cancer. “Those whose blood tests showed a disappearance of the mutations within two weeks were more likely to stay on the treatment than patients who didn’t see such a reduction,” said the study’s lead author, Adrian Sacher, MD, of Dana-Farber and Brigham and Women’s Hospital.

And because tumors are constantly evolving and acquiring additional mutations, repeated liquid biopsies can provide early detection of a new mutation – such as the EGFR resistance mutation – that can potentially be treated with targeted agents.

“The study data are compelling,” said DF/BWCC pathologist Lynette Sholl, MD, explaining the center’s decision to begin offering ddPCR-based liquid biopsy to all lung cancer patients. “We validated the authors’ findings by cross-comparing results from liquid and tissue biopsies in 34 NSCLC patients. To work as a real-world clinical test, liquid biopsy needs to provide reliable, accurate data and be logistically practical. That’s what we’ve seen with the ddPCR-based blood test.

“The test has great utility both for patients newly diagnosed with NSCLC and for those with a recurrence of the disease,” she continued. “It’s fast, it’s quantitative (it indicates the amount of mutant DNA in a sample), and it can be readily employed at a cancer treatment center.”

The co-authors of the study are Cloud Paweletz, PhD, Allison O’Connell, BSc, and Nora Feeney, BSc, of the Belfer Center for Applied Cancer Science at Dana-Farber; Ryan S. Alden BSc, and Stacy L. Mach BA, of Dana-Farber; Suzanne E. Dahlberg, PhD, of Dana-Farber and Harvard T.H. Chan School of Public Health; and Pasi A. Jänne, MD, PhD, of Dana-Farber, the Belfer Center, and Brigham and Women’s Hospital.

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New Risk Stratification for Breast Cancer

Larry H. Bernstein, MD, FCAP, Curator

LPBI

 

MD Anderson Researchers Develop New Breast Cancer Staging System

https://www.genomeweb.com/cancer/md-anderson-researchers-develop-new-breast-cancer-staging-system

NEW YORK (GenomeWeb) – Researchers at the University of Texas MD Anderson Cancer Center have developed a new breast cancer staging system that incorporates tumor biology as a critical prognostic indicator for women who undergo neoadjuvant therapy.

Published this week in JAMA Oncology, the Neo-Bioscore staging system incorporates HER2/ERBB2 status, which allows for more precise prognostic stratification of all breast cancer subtypes.

To date, breast cancer patient staging involved considering the size of the primary tumor, metastasis, or disease in the lymph nodes at the time of presentation as the primary factors.However, this fails to take into account the biology of the tumor, which has shown to be critically important, Elizabeth Mittendorf, associate professor of Breast Surgical Oncology at MD Anderson and corresponding author on the study, said in a statement.

The new system builds on the development of an earlier breast cancer staging system developed by MD Anderson, CPS+EG, that incorporates preclinical stage, estrogen receptor status, grade, and post-treatment pathologic stage. While it was an improvement from previous methods, it is no longer a sufficient staging system because it predates the routine use of trastuzumab in the neoadjuvant setting and therefore had a limited ability to provide prognostic information for HER2/ERBB2-positive patients, Mittendorf said.

To develop the staging system, the researchers conducted a retrospective study that evaluated 2,377 MD Anderson breast cancer patients who all had non-metastatic invasive breast cancer and were treated with neoadjuvant chemotherapy.

Each patient’s clinicopathologic data were recorded, including age, clinical and pathological stage, ER status, HER2/ERBB2 status, and nuclear grade. Patients’ ER status was recorded as a percentage of cells staining positive under immunohistochemical analysis. Their ERBB2 status was defined as positive at a reading of 3+ on immunohistochemical analysis or when gene amplification was shown on fluorescence in situ hybridization.

All patients received an anthracycline and/or taxane-based neoadjuvant chemotherapy regimen. Patients with HER2/ERBB2-positive disease routinely completed one year of trastuzumab therapy. After completing chemotherapy, patients underwent either breast-conserving therapy or mastectomy with axillary evaluation with or without post-mastectomy irradiation.

Patients’ CPS+EG score was determined according to the previously published staging system and was calculated twice (once using 1 percent or higher as the cutoff for ER positivity and again using 10 percent or higher as the cutoff).

Their disease-specific survival (DSS) was also calculated using multiple staging systems: AJCC clinical stage, AJCC pathologic stage, CPS+EG (1 percent cutoff), and CPS+EG (10 percent cutoff). Within each staging system, DSS among subgroups was compared using the log-rank test.

After the researchers determined a CPS+EG score for each patient, they added the patient’s respective HER2/ERBB2 status to the model. They then constructed the novel staging system by adding a point to the CPS+EG score for HER2-negative tumors. In the study cohort, 591 patients were HER2/ERBB2 positive.

The researchers found that in addition to validating previous findings that CPS+EG score improved prognostication of patients, the Neo-Bioscore created a more refined stratification in approximately 75 percent of the study cohort. This shift reflects the number of HER2/ERBB2-negative tumors in the study and demonstrated that adding HER2/ERBB2 standards created a highly significant improvement.

“With this tool, I can give my patients the precise information they are looking for: a more refined prognosis. Also, with this data, we will know which patients are in greatest need of additional therapy,” Mittendorf said. “Hopefully these findings will result in more informed conversations between doctor and patient.”

 

The Neo-Bioscore Update for Staging Breast Cancer Treated With Neoadjuvant ChemotherapyIncorporation of Prognostic Biologic Factors Into Staging After Treatment 

Elizabeth A. Mittendorf, MD, PhD1; Jose Vila, MD1; Susan L. Tucker, PhD2; ….; W. Fraser Symmans, MD6; Aysegul A. Sahin, MD6; Gabriel N. Hortobagyi, MD3; Kelly K. Hunt, MD
JAMA Oncol. Published online March 17, 2016.              http://dx.doi.org:/10.1001/jamaoncol.2015.6478

Importance  We previously described and validated a breast cancer staging system (CPS+EG, clinical-pathologic scoring system incorporating estrogen receptor–negative disease and nuclear grade 3 tumor pathology) for assessing prognosis after neoadjuvant chemotherapy using pretreatment clinical stage, posttreatment pathologic stage, estrogen receptor (ER) status, and grade. Development of the CPS+EG staging system predated routine administration of trastuzumab in patients with ERBB2-positive disease (formerly HER2 or HER2/neu).

Objective  To validate the CPS+EG staging system using the new definition of ER positivity (≥1%) and to develop an updated staging system (Neo-Bioscore) that incorporates ERBB2 status into the previously developed CPS+EG.

Design, Setting, and Participants  Retrospective review of data collected prospectively from January 2005 through December 2012 on patients with breast cancer treated with neoadjuvant chemotherapy at The University of Texas MD Anderson Cancer Center.

Main Outcomes and Measure  Prognostic scores were computed using 2 versions of the CPS+EG staging system, one with ER considered positive if it measured 10% or higher, the other with ER considered positive if it measured 1% or higher. Fits of the Cox proportional hazards model for the 2 sets of prognostic scores were compared using the Akaike Information Criterion (AIC). Status of ERBB2 was added to the model, and the likelihood ratio test was used to determine improvement in fit.

Results  A total of 2377 patients were included; all were women (median age, 50 years [range, 21-87 years]); ER status was less than 1% in 28.9%, 1% to 9% in 8.3%, and 10% or higher in 62.8%; 591 patients were ERBB2 positive. Median follow-up was 4.2 years (range, 0.5-11.7 years). Five-year disease-specific survival was 89% (95% CI, 87%-90%). Using 1% or higher as the cutoff for ER positivity, 5-year disease-specific survival estimates determined using the CPS+EG stage ranged from 52% to 98%, thereby validating our previous finding that the CPS+EG score facilitates more refined categorization into prognostic subgroups than clinical or final pathologic stage alone. The AIC value for this model was 3333.06, while for a model using 10% or higher as the cutoff for ER positivity, it was 3333.38, indicating that the model fits were nearly identical. The improvement in fit of the model when ERBB2 status was added was highly significant, with 5-year disease-specific survival estimates ranging from 48% to 99% (P < .001). Incorporating ERBB2 into the staging system defined the Neo-Bioscore, which provided improved stratification of patients with respect to prognosis.

Conclusions and Relevance  The Neo-Bioscore improves our previously validated staging system and allows its application in ERBB2-positive patients. We recommend that treatment response and biologic markers be incorporated into the American Joint Committee on Cancer staging system.

 

Transforming Breast Cancer Treatment

Landmark preclinical study cured lung metastases in 50 percent of breast cancers by making nanoparticles inside the tumor.

http://www.technologynetworks.com/news.aspx?ID=189462

A team of investigators from Houston Methodist Research Institute may have transformed the treatment of metastatic triple negative breast cancer by creating the first drug to successfully eliminate lung metastases in mice.

The majority of cancer deaths are due to metastases to the lung and liver, yet there is no cure. Existing cancer drugs provide limited benefit due to their inability to overcome biological barriers in the body and reach the cancer cells in sufficient concentrations. Houston Methodist nanotechnology and cancer researchers have solved this problem by developing a drug that generates nanoparticles inside the lung metastases in mice.

In this study, 50 percent of the mice treated with the drug had no trace of metastatic disease after eight months. That’s equivalent to about 24 years of long-term survival following metastatic disease for humans.

Due to the body’s own defense mechanisms, most cancer drugs are absorbed into healthy tissue causing negative side effects, and only a fraction of the administered drug actually reaches the tumor, making it less effective, said Mauro Ferrari, Ph.D, president and CEO of the Houston Methodist Research Institute. This new treatment strategy enables sequential passage of the biological barriers to transport the killing agent into the heart of the cancer. The active drug is only released inside the nucleus of the metastatic disease cell, avoiding the multidrug resistance mechanism of the cancer cells. This strategy effectively kills the tumor and provides significant therapeutic benefit in all mice, including long-term survival in half of the animals.

This finding comes 20 years after Ferrari started his work in nanomedicine. Ferrari and Haifa Shen, M.D., Ph.D., are co-senior authors on the paper, which describes the action of the injectable nanoparticle generator (iNPG), and how a complex method of transporting a nano-version of a standard chemotherapy drug led to never before seen results in mice models with triple negative breast cancer that had metastasized to the lungs.

“This may sound like science fiction, like we’ve penetrated and destroyed the Death Star, but what we discovered is transformational. We invented a method that actually makes the nanoparticles inside the cancer and releases the drug particles at the site of the cellular nucleus. With this injectable nanoparticle generator, we were able to do what standard chemotherapy drugs, vaccines, radiation, and other nanoparticles have all failed to do,” said Ferrari.

Houston Methodist has developed good manufacturing practices (GMP) for this drug and plans to fast-track the research to obtain FDA-approval and begin safety and efficacy studies in humans in 2017.

“I would never want to overpromise to the thousands of cancer patients looking for a cure, but the data is astounding,” said Ferrari, senior associate dean and professor of medicine, Weill Cornell Medicine. “We’re talking about changing the landscape of curing metastatic disease, so it’s no longer a death sentence.”

The Houston Methodist team used doxorubicin, a cancer therapeutic that has been used for decades but has adverse side effects to the heart and is not an effective treatment against metastatic disease. In this study, doxorubicin was packaged within the injectable nanoparticle generator that is made up of many components.

Shen, a senior member of the department of nanomedicine at Houston Methodist Research Institute, explains that each component has a specific and essential role in the drug delivery process. The first component is the nanoporous silicon material that naturally degrades in the body. The second component is a polymer made up of multiple strands that contain doxorubicin. Once inside the tumor, the silicon material degrades, releasing the strands. Due to natural thermodynamic forces, these strands curl-up to form nanoparticles that are taken up by the cancer cells. Once inside the cancer cells, the acidic pH close to the nucleus causes the drug to be released from the nanoparticles. Inside the nucleus, the active drug acts to kill the cell.

“If this research bears out in humans and we see even a fraction of this survival time, we are still talking about dramatically extending life for many years. That’s essentially providing a cure in a patient population that is now being told there is none,” said Ferrari, who holds the Ernest Cockrell Jr. Presidential Distinguished Chair and is considered one of the founders of nanomedicine and oncophysics (physics of mass transport within a cancer lesion).

The Houston Methodist team is hopeful that this new drug could help cancer physicians cure lung metastases from other origins, and possibly primary lung cancers as well.

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