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New Mutant KRAS Inhibitors Are Showing Promise in Cancer Clinical Trials: Hope For the Once ‘Undruggable’ Target

Curator: Stephen J. Williams, Ph.D.

The November 1st issue of Science highlights a series of findings which give cancer researchers some hope in finally winning a thirty year war with the discovery of drugs that target KRAS, one of the most commonly mutated oncogenes  (25% of cancers), and thought to be a major driver of tumorigenesis. Once considered an undruggable target, mainly because of the smooth surface with no obvious pockets to fit a drug in, as well as the plethora of failed attempts to develop such an inhibitor, new findings with recently developed candidates, highlighted in this article and other curated within, are finally giving hope to researchers and oncologists who have been hoping for a clinically successful inhibitor of this once considered elusive target.

 

For a great review on development of G12C KRas inhibitors please see Dr. Hobb’s and Channing Der’s review in Cell Selective Targeting of the KRAS G12C Mutant: Kicking KRAS When It’s Down

Figure 1Mechanism of Action of ARS853 showing that the inhibitors may not need bind to the active conformation of KRAS for efficacy

Abstract: Two recent studies evaluated a small molecule that specifically binds to and inactivates the KRAS G12C mutant. The new findings argue that the perception that mutant KRAS is persistently frozen in its active GTP-bound form may not be accurate.

 

Although the development of the KRASG12C-specific inhibitor, compound 12 (Ostrem et al., 2013), was groundbreaking, subsequent studies found that the potency of compound 12 in cellular assays was limited (Lito et al., 2016, Patricelli et al., 2016). A search for more-effective analogs led to the development of ARS853 (Patricelli et al., 2016), which exhibited a 600-fold increase of its reaction rate in vitro over compound 12 and cellular activities in the low micromolar range.

 

A Summary and more in-depth curation of the Science article is given below:

After decades, progress against an ‘undruggable’ cancer target

Summary

Cancer researchers are making progress toward a goal that has eluded them for more than 30 years: shrinking tumors by shutting off a protein called KRAS that drives growth in many cancer types. A new type of drug aimed at KRAS made tumors disappear in mice and shrank tumors in lung cancer patients, two companies report in papers published this week. It’s not yet clear whether the drugs will extend patients’ lives, but the results are generating a wave of excitement. And one company, Amgen, reports an unexpected bonus: Its drug also appears to stimulate the immune system to attack tumors, suggesting it could be even more powerful if paired with widely available immunotherapy treatments.

Jocelyn Kaiser. After decades, progress against an ‘undruggable’ cancer target. Science  01 Nov 2019: Vol. 366, Issue 6465, pp. 561 DOI: 10.1126/science.366.6465.561

The article highlights the development of three inhibitors: by Wellspring Biosciences, Amgen, and Mirati Therapeutics.

Wellspring BioSciences

 

In 2013, Dr. Kevan Shokat’s lab at UCSF discovered a small molecule that could fit in the groove of the KRAS mutant G12C.  The G12C as well as the G12D is a common mutation found in KRAS in cancers. KRAS p.G12C mutations predominate in NSCLC comprising 11%–16% of lung adenocarcinomas (45%–50% of mutant KRAS is p.G12C) (Campbell et al., 2016; Jordan et al., 2017), as well as 1%–4% of pancreatic and colorectal adenocarcinomas, respectively (Bailey et al., 2016; Giannakis et al., 2016).  This inhibitor was effective in shrinking, in mouse studies conducted by Wellspring Biosciences,  implanted tumors containing this mutant KRAS.

 

See Wellspring’s news releases below:

March, 2016 – Publication – Selective Inhibition of Oncogenic KRAS Output with Small Molecules Targeting the Inactive State

February, 2016 – Publication – Allele-specific inhibitors inactivate mutant KRAS G12C by a trapping mechanism

Amgen

 

Amgen press release on AMG510 Clinical Trial at ASCO 2019

 

THOUSAND OAKS, Calif., June 3, 2019 /PRNewswire/ — Amgen (NASDAQ: AMGN) today announced the first clinical results from a Phase 1 study evaluating investigational AMG 510, the first KRASG12C inhibitor to reach the clinical stage. In the trial, there were no dose-limiting toxicities at tested dose levels. AMG 510 showed anti-tumor activity when administered as a monotherapy in patients with locally-advanced or metastatic KRASG12C mutant solid tumors. These data are being presented during an oral session at the 55th Annual Meeting of the American Society of Clinical Oncology (ASCO) in Chicago.

“KRAS has been a target of active exploration in cancer research since it was identified as one of the first oncogenes more than 30 years ago, but it remained undruggable due to a lack of traditional small molecule binding pockets on the protein. AMG 510 seeks to crack the KRAS code by exploiting a previously hidden groove on the protein surface,” said David M. Reese, M.D., executive vice president of Research and Development at Amgen. “By irreversibly binding to cysteine 12 on the mutated KRAS protein, AMG 510 is designed to lock it into an inactive state. With high selectivity for KRASG12C, we believe investigational AMG 510 has high potential as both a monotherapy and in combination with other targeted and immune therapies.”

The Phase 1, first-in-human, open-label multicenter study enrolled 35 patients with various tumor types (14 non-small cell lung cancer [NSCLC], 19 colorectal cancer [CRC] and two other). Eligible patients were heavily pretreated with at least two or more prior lines of treatment, consistent with their tumor type and stage of disease. 

Canon, J., Rex, K., Saiki, A.Y. et al. The clinical KRAS(G12C) inhibitor AMG 510 drives anti-tumour immunity. Nature 575, 217–223 (2019) doi:10.1038/s41586-019-1694-1

Besides blocking tumor growth, AMG510 appears to stimulate T cells to attack the tumor, thus potentially supplying a two pronged attack to the tumor, inhibiting oncogenic RAS and stimulating anti-tumor immunity.

 

Mirati Therapeutics

 

Mirati’s G12C KRAS inhibitor (MRTX849) is being investigated in a variety of solid malignancies containing the KRAS mutation.

 

For recent publication on results in lung cancer see Patricelli M.P., et al. Cancer Discov. 2016; (Published online January 6, 2016)

For more information on Mirati’s KRAS G12C inhibitor see https://www.mirati.com/pipeline/kras-g12c/

 

KRAS G12C Inhibitor (MRTX849)

Study 849-001 – Phase 1b/2 of single agent MRTX849 for solid tumors with KRAS G12C mutation

Phase 1b/2 clinical trial of single agent MRTX849 in patients with advanced solid tumors that have a KRAS G12C mutation.

See details for this study at clinicaltrials.gov

 

Additional References:

Allele-specific inhibitors inactivate mutant KRAS G12C by a trapping mechanism.

Lito P et al. Science. (2016)

Targeting KRAS Mutant Cancers with a Covalent G12C-Specific Inhibitor.

Janes MR et al. Cell. (2018)

Potent and Selective Covalent Quinazoline Inhibitors of KRAS G12C.

Zeng M et al. Cell Chem Biol. (2017)

Campbell, J.D., Alexandrov, A., Kim, J., Wala, J., Berger, A.H., Pedamallu, C.S., Shukla, S.A., Guo, G., Brooks, A.N., Murray, B.A., et al.; Cancer Genome Atlas Research Network (2016). Distinct patterns of somatic genome alterations in lung adenocarcinomas and squamous cell carcinomas. Nat. Genet.48, 607–616

Jordan, E.J., Kim, H.R., Arcila, M.E., Barron, D., Chakravarty, D., Gao, J., Chang, M.T., Ni, A., Kundra, R., Jonsson, P., et al. (2017). Prospective comprehensive molecular characterization of lung adenocarcinomas for efficient patient matching to approved and emerging therapies. Cancer Discov. 7, 596–609.

Bailey, P., Chang, D.K., Nones, K., Johns, A.L., Patch, A.M., Gingras, M.C., Miller, D.K., Christ, A.N., Bruxner, T.J., Quinn, M.C., et al.; Australian Pancreatic Cancer Genome Initiative (2016). Genomic analyses identify molecular subtypes of pancreatic cancer. Nature 531, 47–52.

Giannakis, M., Mu, X.J., Shukla, S.A., Qian, Z.R., Cohen, O., Nishihara, R., Bahl, S., Cao, Y., Amin-Mansour, A., Yamauchi, M., et al. (2016). Genomic correlates of immune-cell infiltrates in colorectal carcinoma. Cell Rep. 15, 857–865.

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Cancer Genomics: Multiomic Analysis of Single Cells and Tumor Heterogeneity

Curator: Stephen J. Williams, PhD

 

scTrio-seq identifies colon cancer lineages

Single-cell multiomics sequencing and analyses of human colorectal cancer. Shuhui Bian et al. Science  30 Nov 2018:Vol. 362, Issue 6418, pp. 1060-1063

To better design treatments for cancer, it is important to understand the heterogeneity in tumors and how this contributes to metastasis. To examine this process, Bian et al. used a single-cell triple omics sequencing (scTrio-seq) technique to examine the mutations, transcriptome, and methylome within colorectal cancer tumors and metastases from 10 individual patients. The analysis provided insights into tumor evolution, linked DNA methylation to genetic lineages, and showed that DNA methylation levels are consistent within lineages but can differ substantially among clones.

Science, this issue p. 1060

Abstract

Although genomic instability, epigenetic abnormality, and gene expression dysregulation are hallmarks of colorectal cancer, these features have not been simultaneously analyzed at single-cell resolution. Using optimized single-cell multiomics sequencing together with multiregional sampling of the primary tumor and lymphatic and distant metastases, we developed insights beyond intratumoral heterogeneity. Genome-wide DNA methylation levels were relatively consistent within a single genetic sublineage. The genome-wide DNA demethylation patterns of cancer cells were consistent in all 10 patients whose DNA we sequenced. The cancer cells’ DNA demethylation degrees clearly correlated with the densities of the heterochromatin-associated histone modification H3K9me3 of normal tissue and those of repetitive element long interspersed nuclear element 1. Our work demonstrates the feasibility of reconstructing genetic lineages and tracing their epigenomic and transcriptomic dynamics with single-cell multiomics sequencing.

Fig. 1 Reconstruction of genetic lineages with scTrio-seq2.

Global SCNA patterns (250-kb resolution) of CRC01. Each row represents an individual cell. The subclonal SCNAs used for identifying genetic sublineages were marked and indexed; for details, see fig. S6B. On the top of the heatmap, the amplification or deletion frequency of each genomic bin (250 kb) of the non-hypermutated CRC samples from the TCGA Project and patient CRC01’s cancer cells are shown.

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Fig. 1 Reconstruction of genetic lineages with scTrio-seq2.

Global SCNA patterns (250-kb resolution) of CRC01. Each row represents an individual cell. The subclonal SCNAs used for identifying genetic sublineages were marked and indexed; for details, see fig. S6B. On the top of the heatmap, the amplification or deletion frequency of each genomic bin (250 kb) of the non-hypermutated CRC samples

 

 

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Real Time Coverage @BIOConvention #BIO2019: Gene Therapy 2.0: No Longer Science Fiction 1:00-2:15 pm June 3 Philadelphia PA

Reporter: Stephen J. Williams Ph.D. @StephenJWillia2

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Other Articles on Gene Therapy on this Open Access Journal Include:

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Complex rearrangements and oncogene amplification revealed by long-read DNA and RNA sequencing of a breast cancer cell line

Reporter: Stephen J. Williams, PhD

In a Genome Research report by Marie Nattestad et al. [1], the SK-BR-3 breast cancer cell line was sequenced using a long read single molecule sequencing protocol in order to develop one of the most detailed maps of structural variations in a cancer genome to date.  The authors detected over 20,000 variants with this new sequencing modality, whereas most of these variants would have been missed by short read sequencing.  In addition, a complex sequence of nested duplications and translocations occurred surrounding the ERBB2 (HER2) while full-length transcriptomic analysis revealed novel gene fusions within the nested genomic variants.  The authors suggest that combining this long-read genome and transcriptome sequencing results in a more comprehensive coverage of tumor gene variants and “sheds new light on the complex mechanisms involved in cancer genome evolution.”

Genomic instability is a hallmark of cancer [2], which lead to numerous genetic variations such as:

  • Copy number variations
  • Chromosomal alterations
  • Gene fusions
  • Deletions
  • Gene duplications
  • Insertions
  • Translocations

Efforts such as the Cancer Genome Atlas [3], and the International Genome Consortium (2010) use short-read sequencing technology to detect and analyze thousands of commonly occurring mutations however short-read technology has a high false positive and negative rate for detecting less common genetic structural variations {as high as 50% [4]}. In addition, short reads cannot detect variations in close proximity to each other or on the same molecule, therefore underestimating the variation number.

Methods:  The authors used a long-read sequencing technology from Pacific Biosciences (SMRT) to analyze the mutational and structural variation in the SK-BR-3 breast cancer cell line.  A split read and within-read mapping approach was used to detect variants of different types and sizes.  In general, long-reads have better alignment qualities than short reads, resulting in higher quality mapping. Transcriptomic analysis was performed using Iso-Seq.

Results: Using the SMRT long-read sequencing technology from Pacific Biosciences, the authors were able to obtain 71.9% sequencing coverage with average read length of 9.8 kb for the SK-BR-3 genome.

A few notes:

  1. Most amplified regions (33.6 copies) around the locus spanning the ERBB2 oncogene and around MYC locus (38 copies), EGFR locus (7 copies) and BCAS1 (16.8 copies)
  2. The locus 8q24.12 had the most amplifications (this locus contains the SNTB1 gene) at 69.2 copies
  3. Long-read sequencing showed more insertions than deletions and suggests an underestimate of the lengths of low complexity regions in the human reference genome
  4. Found 1,493 long read variants, 603 of which were between different chromosomes
  5. Using Iso-Seq in conjunction with the long-read platform, they detected 1,692,379 isoforms (93%) mapping to the reference genome and 53 putative gene fusions (39 of which they found genomic evidence)

A table modified from the paper on the gene fusions is given below:

Table 1. Gene fusions with RNA evidence from Iso-Seq and DNA evidence from SMRT DNA sequencing where the genomic path is found using SplitThreader from Sniffles variant calls. Note link in table is  GeneCard for each gene.

SplitThreader path

 

# Genes Distance
(bp)
Number
of variants
Chromosomes
in path
Previously observed in references
1 KLHDC2 SNTB1 9837 3 14|17|8 Asmann et al. (2011) as only a 2-hop fusion
2 CYTH1 EIF3H 8654 2 17|8 Edgren et al. (2011); Kim and Salzberg
(2011); RNA only, not observed as 2-hop
3 CPNE1 PREX1 1777 2 20 Found and validated as 2-hop by Chen et al. 2013
4 GSDMB TATDN1 0 1 17|8 Edgren et al. (2011); Kim and Salzberg
(2011); Chen et al. (2013); validated by
Edgren et al. (2011)
5 LINC00536 PVT1 0 1 8 No
6 MTBP SAMD12 0 1 8 Validated by Edgren et al. (2011)
7 LRRFIP2 SUMF1 0 1 3 Edgren et al. (2011); Kim and Salzberg
(2011); Chen et al. (2013); validated by
Edgren et al. (2011)
8 FBXL7 TRIO 0 1 5 No
9 ATAD5 TLK2 0 1 17 No
10 DHX35 ITCH 0 1 20 Validated by Edgren et al. (2011)
11 LMCD1-AS1 MECOM 0 1 3 No
12 PHF20 RP4-723E3.1 0 1 20 No
13 RAD51B SEMA6D 0 1 14|15 No
14 STAU1 TOX2 0 1 20 No
15 TBC1D31 ZNF704 0 1 8 Edgren et al. (2011); Kim and Salzberg
(2011); Chen et al. (2013); validated by
Edgren et al. (2011); Chen et al. (2013)

 

SplitThreader found two different paths for the RAD51B-SEMA6D gene fusion and for the LINC00536-PVT1 gene fusion. Number of Iso-Seq reads refers to full-length HQ-filtered reads. Alignments of SMRT DNA sequence reads supporting each of these gene fusions are shown in Supplemental Note S2.

 

 References

 

  1. Nattestad M, Goodwin S, Ng K, Baslan T, Sedlazeck FJ, Rescheneder P, Garvin T, Fang H, Gurtowski J, Hutton E et al: Complex rearrangements and oncogene amplifications revealed by long-read DNA and RNA sequencing of a breast cancer cell line. Genome research 2018, 28(8):1126-1135.
  2. Hanahan D, Weinberg RA: The hallmarks of cancer. Cell 2000, 100(1):57-70.
  3. Kandoth C, McLellan MD, Vandin F, Ye K, Niu B, Lu C, Xie M, Zhang Q, McMichael JF, Wyczalkowski MA et al: Mutational landscape and significance across 12 major cancer types. Nature 2013, 502(7471):333-339.
  4. Sudmant PH, Rausch T, Gardner EJ, Handsaker RE, Abyzov A, Huddleston J, Zhang Y, Ye K, Jun G, Fritz MH et al: An integrated map of structural variation in 2,504 human genomes. Nature 2015, 526(7571):75-81.

 

Other articles on Cancer Genome Sequencing in this Open Access Journal Include:

 

International Cancer Genome Consortium Website has 71 Committed Cancer Genome Projects Ongoing

Loss of Gene Islands May Promote a Cancer Genome’s Evolution: A new Hypothesis on Oncogenesis

Identifying Aggressive Breast Cancers by Interpreting the Mathematical Patterns in the Cancer Genome

CancerBase.org – The Global HUB for Diagnoses, Genomes, Pathology Images: A Real-time Diagnosis and Therapy Mapping Service for Cancer Patients – Anonymized Medical Records accessible to

 

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The Sylvester Comprehensive Cancer Center of the University of Miami named 71st NCI designated Cancer Center

 

Reporter: Stephen J. Williams, PhD

As seen in the Cancer Letter at https://cancerletter.com/articles/20190729_1/

Conversation with The Cancer Letter

Sylvester becomes 71st NCI-designated cancer center

Stephen Nimer

Director,

Sylvester Comprehensive Cancer Center

 

After six years of  aggressively recruiting and spending more than $250 million to build up its programs, Sylvester Comprehensive Cancer Center has become the 71st NCI-designated cancer center in the US and the only such institution in South Florida.

The designation was announced July 29.

Sylvester, which is a part of the University of Miami Leonard M. Miller School of Medicine, is one of 64 cancer centers with the NCI Cancer Center designation in the nation. Fifty of these centers hold the Comprehensive Cancer Center designation. Seven more are designated as Basic Laboratory Cancer Centers.

“There are over 21 million people who live in the state of Florida. In 2014, Florida became the third largest state in the United States, surpassing New York—yet New York has seven NCI designated cancer centers and Florida had had only one,” Stephen D. Nimer, director of Sylvester, said to The Cancer Letter.

“There are over six million people in our catchment area, South Florida, and if they wanted to go to an NCI-designated cancer center they’d have to either get on a plane or drive nearly 300 miles—to Tampa.”

Public health programs that helped Sylvester secure the NCI designation include the Game Changer vehicle, which brings evidence-based interventions to underserved communities in the cancer center’s catchment area (The Cancer Letter, April 27, 2018). The center’s cancer control program also includes the Firefighter Cancer Initiative, a long-term study of exposures to carcinogens and ways to reduce and prevent cancer risks for Florida firefighters.

 

 

The cancer center is working on deploying another Game Changer vehicle. Recently, Peter Tunney, a New York and Miami-based artist and gallerist who donated a painting for the first Game Changer van, donated another painting that Sylvester can sell to raise money for its programs (The Cancer Letter, April 27, 2018).

 

“When they got that designation, they were walking on sunshine,” Tunney said to The Cancer Letter. “I think it’s a universal idea. I think that’s the goal for all of us—for all of mankind, for sick and healthy—to have that feeling that is so rare today: I am walking on sunshine. It’s almost like a thing of the past. Who can walk on sunshine today, in this crazy world filled with suffering and illness? And I just feel like we can, we can, it’s possible to be grateful for the things we have.

The intense yellow wallpaper motif reminds Tunney of the wallpaper in his grandmother’s house in the 1960s and 1970s, the time when American astronauts walked on the moon. “It’s somebody’s grandmother’s wallpaper from the sixties. We look back at that time, we look back at landing on the moon, and everyone is aflutter, ‘Oh, those were the good old days.’ No, these are the good old days.”

The word “comprehensive” in Sylvester’s name doesn’t refer to its level of NCI designation. When it was founded in 1973, the institution was known as the Comprehensive Cancer Center for the State of Florida. In 1992, after receiving a $27.5 million gift from the philanthropist Harcourt Sylvester Jr., it was renamed Sylvester Comprehensive Cancer Center.

 

Sylvester director Nimer spoke with Paul Goldberg, editor and publisher of The Cancer Letter.

 

Paul Goldberg:

First of all, congratulations.

Stephen Nimer: 

Thank you; it’s a big deal.

 

PG:

How long did it take to get this done?

SN:

I’d say, six years. I arrived in 2012, seven years ago, and the first year started by assessing what’s going on at Sylvester. We then developed our first five-year strategic plan, which ran from 2014 to 2018, and we submitted our [Cancer Center Support Grant] application in September 2018. We’re now in the midst of our second five-year plan.

 

PG:

And how much money did it require?

SN:

I’d have to add it all up. One of the most important things for us was that the state, in 2014, started giving us a bit over $16 million a year so that we could become NCI-designated. The health system, over a five-to-six-year period, probably gave us somewhere between $90 and $100 million. And then we’ve raised philanthropy. The philanthropy over five to six years, is maybe close to $100 million. So, it’s probably $250 -$270 million.

 

PG:

How many people did you have to recruit?

SN:

We went in [to NCI] with 124 members on our CCSG application, but over the last seven years we’ve recruited nearly 150 people. In addition to recruiting researchers I’ve been given the opportunity to build the clinical programs also.

Many of the clinical people are not included on the grant, because the grant has very specific requirements to be a member. For example, we’ve hired a couple of breast cancer surgeons, and they are not listed on the grant, because they are not yet doing significant research.

The NCI doesn’t want to know about people who don’t have grants or aren’t running clinical trials. So, out of the 124, which is what we went in with, I believe nearly 50 of our members were new.

 

PG:

How is your cancer center different from all others?

SN:

One of the things that we got the highest marks on is our community outreach and engagement efforts and how relevant the research we’re doing is to our catchment area.

A couple of examples:

We have a West Indies population, so we have an endemic HTLV-1-infected population, and thus a significant number of HTLV-1-related adult T-cell leukemia patients. So, one of our physician scientists has an R01 studying ATL. And we have a number of clinical trials for people with adult T-cell leukemia.

We also have a large burden of advanced cervical cancer patients in our region, especially in Little Haiti. And so, we have a lot of efforts on early detection of high-risk HPV, prevention and clinical treatment trials for women with cervical cancer.

Another thing that distinguishes us from many centers is the diversity of our faculty, our students, and the patients we put on clinical trials. In our CCSG application, roughly 30% of the patients on interventional trials were black and 40% were Hispanic—so both racial and ethnic diversity. We also have incredible socio-economic diversity.

What’s unique among the black population in our catchment area is that it is Afro-Caribbean more than African American—different genetics, different cultures.

The Hispanic population is unique as well. MD Anderson is probably largely Mexican Americans. New York is probably mostly Dominican and Puerto Rican. We have significant populations of Cuban Americans, Venezuelans, Brazilians, Argentinians, Colombians—an incredibly diverse group.

One example of how this plays out is in our prostate cancer research. The watch-and-wait approach is an appropriate strategy for many people. We found that our black population has more anterior prostate cancer lesions, so when you do blind biopsies, you’re more likely to miss lesions.

And then we’ve looked among the Hispanic populations as to who has a better or worse prognosis and we’ve identified subgroups within the Hispanic population that have different genetics and a different biology. So, we are tailoring our approach. Based on genetic ancestry as well as other factors.

The other thing is, we have a very strong cancer epigenetics programs, a very strong program on infections and cancer, including H. Pylori, HPV, and hepatitis viruses B and C.

We are very focused on developing programs that meet the needs of the people in this six-million-plus community.

Our catchment area is four counties, somewhat famous, because of the election news nearly every cycle: Broward, Palm Beach County, Miami Dade and Monroe County.

 

PG:

New York, where you come from, has an NCI-designated cancer center on every street corner. And Miami—make that South Florida—has just one now. How is Florida different? You would have thought that there would be multiple NCI-designated cancer centers in South Florida.

SN:

Your point is very well taken. There are over 21 million people who live in the state of Florida. In 2014, Florida became the third largest state in the United States, surpassing New York—yet New York has seven NCI designated cancer centers and Florida had had only one.

Moffitt had gotten a huge investment from the state in the past, and that enabled them to become NCI-designated. And upon designation, they could recruit more researchers, attract more patients, and get more philanthropy, and get all the positives from that. And for the longest time, Florida has only had one.

There are over six million people in our catchment area, South Florida, and if they wanted to go to an NCI-designated cancer center they’d have to either get on a plane or drive nearly 300 miles—to Tampa.

Now, one problem that we face in our region, which is very splintered in terms of market share, etc. is that there’s a lot of community hospitals here that have cancer centers, but they are not necessarily conducting cancer research in any way.

I’ve been reading Joe Simone’s Journal of Clinical Oncology paper from 2002, where he talks about the fact that there are no criteria to call yourself a cancer center. And because people may feel like you can get great care anywhere, they may not seek out the experts.

Probably, in many markets throughout the US, there’s still an ongoing process of trying to educate people as to what’s the difference between an NCI-designated cancer center and one that’s not. And, obviously, the designation is given, because of the research that’s going on. And so, people wonder: “What is the connection between the research and me being a patient there?”

A big part of educating our community is to tell people that oftentimes the doctors who are doing research on a specific cancer have a deeper knowledge about its management. Also, experts more often make the correct diagnosis and come up with more exact multidisciplinary treatment approaches for many cancers.

NCI-designated cancer centers have more clinical trials and more investigator-initiated clinical trials. Now, with NCI designation, we’ll have access to the [NCI Cancer Therapy Evaluation Program] drugs and treatments. Already, we have a very robust phase I clinical trials program, having put 161 patients on phase I trials last year.

This means that we are doing more innovative things, not accepting the status quo, which is what you often get in community hospitals.

I get asked all the time: “Don’t only complicated cancers need to get seen in Sylvester?” and I usually say, “Any cancer that you have is complicated.”

There are other things we need to stress:  Sometimes patients spend more time figuring out which flat screen TV they’re going to buy than they do figuring out who should be taking care of them. And so, we tell patients to ask: “How sure are you that you have made the correct diagnosis?”

So many people are misdiagnosed in the US each year, and sometimes people are treated who don’t need to be treated and vice-versa.

For instance, we are working with Moffitt and the University of Florida on pancreas cancer. We’re hoping to look at how many patients in our state are told that with radiation, chemotherapy, and surgery there’s a potential for cure, as opposed to being told that pancreatic cancer is terrible, and you better get your affairs in order.

While the NCI designation, of course, relates to multidisciplinary and collaborative research efforts, we have—given the diversity of our catchment area and community—an important task to educate people in culturally appropriate ways.

 

PG:

Well, there’s a lot happening that actually very good. Having the University of Florida on the path to designation is also wonderful for the state. There’s so much room in there for growth.

SN:

Absolutely. Absolutely.

 

PG:

Since we are talking about Joe Simone’s paper, the word “comprehensive” is in the name of your cancer center. Yet, you don’t—yet—have the NCI-koshered comprehensive designation. Can you change the name? Do you need to?

SN:

The University of Miami’s cancer center started in 1973 shortly after Nixon signed the National Cancer Act. Later, with a naming gift from the Sylvester family, we opened our doors as the Sylvester Comprehensive Cancer Center in 1992. The comprehensive in our name does not refer to an NCI designation. It’s been our name because we have always delivered comprehensive cancer care.

 

PG:

Let’s talk about the Game Changer. That’s such a cool thing. That was one of your center’s great ideas.

SN:

The Game Changer vehicle has been really incredible, already in its impact on our cancer education and early detection programs (The Cancer Letter, April 27, 2018). We’re accruing people for research, and we’re already following some of their health habits.

We’re in the process of delivering HPV vaccines. We have been working with our AIDS group, so you can get PrEP. And we go into communities, like Little Havana, Liberty City, Little Haiti. We are also going into areas to provide education on HIV. As you know, the incidence of HIV in the Miami Dade area is the highest in the nation. So, the vehicle is already having an impact in so many ways.

We’ve just gotten the second Game Changer!

Peter Tunney, the artist, is going to wrap this one also. And this one’s going to focus primarily on Monroe County, which has been hit hard by hurricanes, and also has very poor medical infrastructure.

If you travel to Miami, for business or pleasure, you don’t realize that it’s not that far to get to an extraordinarily rural area. The density of population in Monroe county is very low and access to health care is limited.

The areas that we’re trying to reach have so much socioeconomic gap and disparities. And the Game Changer vehicles are going to help us reach people who otherwise do not access traditional medical systems.

You asked me about the Game Changer vehicle as an idea, and I wanted to shout out the leadership team that we’ve been able to put together at Sylvester. They have been incredible. Our people have worked together in amazing ways. And so, when you say, “That’s a great idea of yours,” yours is the whole team, of course.

 

PG:

Of course.

SN:

It’s remarkable how much work it takes to build the research programs that allow us to even have a competitive application. There were so, so many people who spent so much time for the benefit of the cancer center, and not for their own research.

 

PG:

Can we talk about hurricanes? They have an impact on your mission.

SN:

It’s interesting, because the Sylvester Comprehensive Cancer Center opened its doors in 1992, which is just when Hurricane Andrew hit. I’ve looked through our archives: There are some great articles in the Miami newspaper, because we remained open and provided care right after Hurricane Andrew, which has been the most devastating hurricane here in, I don’t know exactly how many years, maybe 30 or 50 or whatever.

But even following the more recent hurricanes, we’ve been able to provide care for our patients. After Hurricane Irma, in one of our satellites we were open the next day, and we treated 30 patients with chemotherapy who needed it, even though many folks were without electricity.

It’s a unique challenge. We have hurricane preparedness for our laboratories. We have drills for the hospital. And we have a command center.

During Irma, because I live on Miami Beach, in a mandatory evacuation zone, I had to leave my home for a few days. And so, my wife and I slept in the hospital for three nights. There’s food, water, and air conditioning in the hospital. It’s not a bad place to be!

 

PG:

You’re driving now to one of the clinics, even as we speak; right? One of the satellite clinics?

SN:

Yes.

 

PG:

Can you tell me about that?

SN:

We have seven sites where we deliver clinical care. The main site in downtown Miami, and then we have three quite large facilities, one in Coral Gables, one in Plantation, one in Deerfield Beach. And we have three other satellites that are smaller, in Coral Springs, Hollywood, and Kendall.

And this allows us to deliver regional care. We’re all on the same EPIC electronic medical record. And we have patients enrolled on clinical trials in the satellites. Not all the satellites at the moment can have a research pharmacy. But the plan is we’re going to continue our expansion of facilities and services and increase the number of accruals and the sophistication of the trials that are available here. Everybody working in these satellites is a University of Miami employee.

The doctors are all part of our site disease groups, and they teleconference in to meetings and lectures. And many of them spend a day in Miami at the main satellite for education and clinical and other purposes.

Many of the doctors in the satellites are principal investigators on the clinical trials. And it’s important because people don’t want to travel necessarily on the freeways here to get to downtown Miami. And so, we can deliver academic care out in the community, which is always important and a challenging thing to do.

 

PG:

Is there anything we’ve forgotten, anything we need to address?

SN:

Maybe I can talk briefly about the state money for a minute. When Sen. [Rick] Scott [(R-FL)] was the governor, he got us together in his office, the University of Florida, Moffitt, and the University of Miami, and asked us what we needed to become major cancer centers and attain NCI designation so we could have three such facilities in the state.

The next year, the state gave us $10. 5 million to split three ways. So, we each got $3.5 million to bring in somebody from outside the state of Florida, a world-class scientist, and provide them with $500,000 a year for seven years.

We brought Ramin Shiekhattar from the Wistar Institute. He’s one of the leaders of our Cancer Epigenetics Program and a year and a half ago, Ramin won one of the highly prestigious NIH Director’s Pioneer Awards. I believe they give 10 out a year.

Next, the state set up a pool of $60 million to be shared between the three institutions each year for five and now six years. These funds are being used so that all three institutions can attain NCI designation. The directors of these cancer centers get along extremely well, and, in a pretty unique model, we created something called the Florida Academic Cancer Center Alliance.

It exists to promote collaborations across our institutions to conduct important cancer research and bring more federal research dollars to the state.

There are one or two other points I’d like to make: Another person we brought in, Gilberto Lopes, is the head of our Global Oncology Program and the editor of the Journal of Global Oncology for ASCO.

He just gave a plenary talk at 2018 ASCO, showing that immunotherapy is better than chemotherapy for the upfront treatment of certain subsets of lung cancer. His talk was one of four plenary talks we’ve recently given at important national cancer meetings.

I think the other message is just the level at which we’re operating on now. We are demonstrating to our community that we have people who are national leaders, and programs that are among the very best in the country. For this, I must thank the incredible team of researchers who work at Sylvester.

I think that, as we recruit more and more people, this designation is going to help us. I’m very pleased that when we submit NIH grants, the reviewers comment upon the environment in Miami, we now get the high scores for the research environment.

 

PG:

This brings up a problem that held back Sylvester for years, which was the lack of independence of the cancer center, or at least it was perceived to be that. Do you have the independence you need now?

SN:

First of all, I would never have left Sloan Kettering without the authority I needed from the leadership of the University of Miami, the health system and the Miller School of Medicine…

 

PG:

Yeah, that’s a good point.

SN:

I should point out, that I am the head of the cancer center, but I’m also the head of the oncology service line for UHealth health system. This arrangement allows me to align the clinical and the research missions in a way that many cancer center directors cannot.

It’s a real privilege, and I have great leadership and great people working on the service line to make our patient care and patient-related activities superb.

 

PG:

Well, that’s hugely important.

Copyright (c) 2018 The Cancer Letter Inc.

More on NCI Designated Cancer Centers can be found here: https://www.cancer.gov/research/nci-role/cancer-centers

Other articles on NCI Cancer Centers on the Open Access Online Journal include:

Salivary Gland Cancer – Adenoid Cystic Carcinoma: Mutation Patterns: Exome- and Genome-Sequencing @ Memorial Sloan-Kettering Cancer Center

Engineered Bacteria used as Trojan Horse for Cancer Immunotherapy

First Cost-Effectiveness Study of Multi-Gene Panel Sequencing in Advanced Non-Small Cell Lung Cancer Shows Moderate Cost-Effectiveness, Exposes Crucial Practice Gap

 

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Efficiency of PARP inhibitors beyond BRCA mutations

Reporter

Irina Robu, PhD

PARP inhibitors are a group of pharmacological inhibitors of the enzyme poly ADP ribose polymerase, which are developed for multiple indications but most visible is the treatment of cancer. Several forms of cancer are extra dependent on PARP than regular cells, making PARP an striking target for cancer therapy. PARP inhibitors seem to improve progression-free survival in women with recurrent platinum-sensitive cancer. In addition to their use in cancer therapy, PARP inhibitors can be a potential treatment for acute life-threatening diseases, such as stroke and myocardial infarction and neurodegenerative diseases.

With this knowledge in hand, Lee Kraus, di­rec­tor of the Green Cen­ter for Re­pro­duc­tive Bi­ol­o­gy Sci­ences at UT South­west­ern his team iden­ti­fied a po­ten­tial bio­mark­er, DDX21 protein, which is re­quired for the pro­duc­tion of ri­bo­somes in nu­cle­oli. Nonetheless, DDX21 in the nu­cle­o­lus re­quires PARP-1, which is tar­get­ed by ex­ist­ing PARP in­hibitors. The use of these drugs, blocks DDX21, hence in­hibit­ing ri­bo­some pro­duc­tion which as result means that en­hanced DDX21 lev­els in the nu­cle­o­lus could regulate can­cers that might be the most re­spon­sive to PARP in­hibitors.

Their data published in the journal Molecular Cell explains why breast cancer patients can be responsive to PARP inhibitors, even though they do not carry BRCA mutation. It is well known that the PARP inhibitors currently on the market such as As­traZeneca’s Lyn­parza, Clo­vis’ Rubra­ca and GSK’s Ze­ju­la work by disturbing PARP pro­teins that help re­pair dam­aged DNA in cell, hence steer­ing can­cer cells on­to a path of an­ni­hi­la­tion. Since cancer cells are addicted to ribosomes to grow and make proteins to support cell division, inhibiting PARP proteins can slow down the growth of the cell.

Kraus’s group is currently working to design clinical trials with UT South­west­ern on­col­o­gists to see if their hypothesis works. At the same time, they founded Ribon Therapeutics which is the first industrial biotech program going af­ter PARP7, a pro­tein al­so sim­i­lar­ly ac­ti­vat­ed by stress and cel­lu­lar re­sponse mech­a­nisms.

SOURCE

PARP inhibitors sometimes work beyond BRCA-mutations, researchers may finally know why

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

Targeting PARP

Curator: Larry H. Bernstein, MD, FCAP

https://pharmaceuticalintelligence.com/2016/05/19/targeting-parp/

 

 

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An Intelligent DNA Nanorobot to Fight Cancer by Targeting HER2 Expression

Reporter and Curator: Dr. Sudipta Saha, Ph.D.

 

HER2 is an important prognostic biomarker for 20–30% of breast cancers, which is the most common cancer in women. Overexpression of the HER2 receptor stimulates breast cells to proliferate and differentiate uncontrollably, thereby enhancing the malignancy of breast cancer and resulting in a poor prognosis for affected individuals. Current therapies to suppress the overexpression of HER2 in breast cancer mainly involve treatment with HER2-specific monoclonal antibodies. However, these monoclonal anti-HER2 antibodies have severe side effects in clinical trials, such as diarrhea, abnormal liver function, and drug resistance. Removing HER2 from the plasma membrane or inhibiting the gene expression of HER2 is a promising alternative that could limit the malignancy of HER2-positive cancer cells.

 

DNA origami is an emerging field of DNA-based nanotechnology and intelligent DNA nanorobots show great promise in working as a drug delivery system in healthcare. Different DNA-based nanorobots have been developed as affordable and facile therapeutic drugs. In particular, many studies reported that a tetrahedral framework nucleic acid (tFNA) could serve as a promising DNA nanocarrier for many antitumor drugs, owing to its high biocompatibility and biosecurity. For example, tFNA was reported to effectively deliver paclitaxel or doxorubicin to cancer cells for reversing drug resistance, small interfering RNAs (siRNAs) have been modified into tFNA for targeted drug delivery. Moreover, the production and storage of tFNA are not complicated, and they can be quickly degraded in lysosomes by cells. Since both free HApt and tFNA can be diverted into lysosomes, so,  combining the HApt and tFNA as a novel DNA nanorobot (namely, HApt-tFNA) can be an effective strategy to improve its delivery and therapeutic efficacy in treating HER2-positive breast cancer.

 

Researchers reported that a DNA framework-based intelligent DNA nanorobot for selective lysosomal degradation of tumor-specific proteins on cancer cells. An anti-HER2 aptamer (HApt) was site-specifically anchored on a tetrahedral framework nucleic acid (tFNA). This DNA nanorobot (HApt-tFNA) could target HER2-positive breast cancer cells and specifically induce the lysosomal degradation of the membrane protein HER2. An injection of the DNA nanorobot into a mouse model revealed that the presence of tFNA enhanced the stability and prolonged the blood circulation time of HApt, and HApt-tFNA could therefore drive HER2 into lysosomal degradation with a higher efficiency. The formation of the HER2-HApt-tFNA complexes resulted in the HER2-mediated endocytosis and digestion in lysosomes, which effectively reduced the amount of HER2 on the cell surfaces. An increased HER2 digestion through HApt-tFNA further induced cell apoptosis and arrested cell growth. Hence, this novel DNA nanorobot sheds new light on targeted protein degradation for precision breast cancer therapy.

 

It was previously reported that tFNA was degraded by lysosomes and could enhance cell autophagy. Results indicated that free Cy5-HApt and Cy5-HApt-tFNA could enter the lysosomes; thus, tFNA can be regarded as an efficient nanocarrier to transmit HApt into the target organelle. The DNA nanorobot composed of HApt and tFNA showed a higher stability and a more effective performance than free HApt against HER2-positive breast cancer cells. The PI3K/AKT pathway was inhibited when membrane-bound HER2 decreased in SK-BR-3 cells under the action of HApt-tFNA. The research findings suggest that tFNA can enhance the anticancer effects of HApt on SK-BR-3 cells; while HApt-tFNA can bind to HER2 specifically, the compounded HER2-HApt-tFNA complexes can then be transferred and degraded in lysosomes. After these processes, the accumulation of HER2 in the plasma membrane would decrease, which could also influence the downstream PI3K/AKT signaling pathway that is associated with cell growth and death.

 

However, some limitations need to be noted when interpreting the findings: (i) the cytotoxicity of the nanorobot on HER2-positive cancer cells was weak, and the anticancer effects between conventional monoclonal antibodies and HApt-tFNA was not compared; (ii) the differences in delivery efficiency between tFNA and other nanocarriers need to be confirmed; and (iii) the confirmation of anticancer effects of HApt-tFNA on tumors within animals remains challenging. Despite these limitations, the present study provided novel evidence of the biological effects of tFNA when combined with HApt. Although the stability and the anticancer effects of HApt-tFNA may require further improvement before clinical application, this study initiates a promising step toward the development of nanomedicines with novel and intelligent DNA nanorobots for tumor treatment.

 

References:

 

https://pubs.acs.org/doi/10.1021/acs.nanolett.9b01320

 

https://www.ncbi.nlm.nih.gov/pubmed/27939064

 

https://www.ncbi.nlm.nih.gov/pubmed/11694782

 

https://www.ncbi.nlm.nih.gov/pubmed/27082923

 

https://www.ncbi.nlm.nih.gov/pubmed/25365825

 

https://www.ncbi.nlm.nih.gov/pubmed/26840503

 

https://www.ncbi.nlm.nih.gov/pubmed/29802035

 

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