Canadian Researchers Link DICER1 Gene Mutation to Non-Epithelial Ovarian Cancers & Other Rare Tumor Types

Canadian researchers affiliated with the Ovarian Cancer Research Program of British Columbia report that recurrent, lifetime-acquired mutations affecting the DICER1 gene occur in a range of nonepithelial ovarian tumors as well as other rare cancer tumor types, and appear common in Sertoli-Leydig ovarian tumors. The study findings were published online today in the New England Journal of Medicine.

Dr. Gregg Morin, Head of Proteomics, Michael Smith Genome Sciences Centre, BC Cancer Agency; DICER 1 Mutation Ovarian Cancer Study Co-Leader

Dr. David Huntsman, Genetic Pathologist & Director of the Ovarian Cancer Research Program of British Columbia at the BC Cancer Agency & Vancouver Coastal Health Research Institute; DICER 1 Mutation Ovarian Cancer Study Co-Leader

Scientists at the British Columbia (BC) Cancer Agency, Vancouver Coastal Health Research Institute, and the University of British Columbia (UBC) are excited over a discovery made while studying rare tumor types.

Dr. David Huntsman, genetic pathologist and director of the Ovarian Cancer Program of BC (OvCaRe) at the BC Cancer Agency and Vancouver Coastal Health Research Institute, and Dr. Gregg Morin, a lead scientist from the Michael Smith Genome Sciences Centre at the BC Cancer Agency, led a research team who discovered that mutations in rare, seemingly unrelated cancers were all linked to the same gene, known as “DICER1.” The study findings were published online today in the New England Journal of Medicine. [1]

Background: RNA Interference, MicroRNAs, and DICER.

Nucleic acids are molecules that carry genetic information and include DNA (deoxyribonucleic acid) and RNA (ribonucleic acid). The DNA segments that carry genetic information are called “genes.” Together these molecules form the building blocks of life. DNA contains the genetic code or “blueprint” used in the development and functioning of all living organisms, while “messenger RNAs” or mRNAs help to translate that genetic code into proteins by acting as a messenger between the DNA instructions located in the cell nucleus and the protein synthesis which takes place in the cell cytoplasm (i.e., outside the cell nucleus, but inside the outer cell membrane). Accordingly, DNA is first “transcribed” or copied into mRNA, which, in turn, gets “translated” or synthesized into protein.

RNA interference” (RNAi) is a mechanism through which gene expression is inhibited at the translation stage, thereby disrupting the protein production within a cell. RNAi is considered one of the most important discoveries in the field of molecular biology. Andrew Fire, Ph.D., and Craig C. Mello, Ph.D. shared the 2006 Nobel Prize in Physiology or Medicine for work that led to the discovery of the RNAi mechanism. While the mechanism itself is termed “RNA interference,” there are two major types of RNA molecules that play a key role in effectuating that interference. The first type of RNA molecules consists of “microRNAs” or miRNAs, while the second type consists of “small interfering RNAs” or siRNAs.

Current thinking suggests that RNAi evolved as a cellular defense mechanism against invaders such as RNA viruses. When they replicate, RNA viruses temporarily exist in a double-stranded form. This double-stranded intermediate would trigger RNAi and inactivate the virus’ genes, thereby preventing viral infection. RNAi may also have evolved to combat the spread of genetic elements called “transposons” within a cell’s DNA. Transposons can wreak havoc by jumping from spot to spot on a genome, sometimes causing mutations that can lead to cancer or other diseases. Like RNA viruses, transposons can take on a double-stranded RNA form that would trigger RNAi to clamp down on the potentially harmful “jumping gene” activity. Also, as noted above, RNAi is important for regulating gene expression. For example, the turning down of specific genes is critical to proper embryonic development.

Of relevance to the Canadian study findings within the context of RNAi are miRNAs. MiRNAs can bind to mRNAs and either increase or decrease their activity, for example, by preventing a mRNA from producing a protein. [2] In this context, “gene silencing” can occur through mRNA degradation or prevention of mRNA translation.  MiRNAs play an integral role in numerous biological processes, including the immune response, cell-cycle control, metabolism, viral replication, stem cell differentiation and human development. MiRNA expression or function is significantly altered in many disease states, including cancer.

Because of its involvement in miRNA processing, the DICER1 gene plays an important role in maintaining health. It carries out a “factory style” function which involves chopping up miRNAs to activate them. [Ref. 2] These miRNAs, in turn, control hundreds of other genes as noted above. Based upon a study led by investigators from the University of Texas M.D. Anderson Cancer Center, the expression levels of DICER have global effects on the biogenesis of miRNA, and reduced gene expression correlates with a poor outcome in ovarian cancer. [3] In the M.D. Anderson study, two somatic (i.e., lifetime-acquired) missense DICER mutations were discovered in two epithelial ovarian cancer tumors. The M.D. Anderson investigators concluded that the DICER mutations were not associated with the alterations in DICER expression found in mRNAs. It is important to note that the type of somatic missense DICER mutations discovered in the M.D. Anderson study were not the same as those discovered in the Canadian study as discussed below.

Recurrent DICER Mutations Are Predominant In A Rare Form of Non-Epithelial Ovarian Cancer.

At the outset of the Canadian study, the OvCaRe team sequenced ovarian, uterine, and testicular tumors, expecting to find that their genomes would be distinct with specific, differing abnormalities. Much to their amazement, the researchers discovered that the same fundamental mutation in the DICER1 gene represented a common process underlying the different cancers which they examined.

Specifically, the Canadian investigators sequenced the whole transcriptomes or exomes of 14 nonepithelial ovarian tumors, which included two Sertoli–Leydig cell tumors, four juvenile (not adult) granulosa-cell tumors, and eight primitive germ-cell tumors of the yolk-sac type. The researchers identified closely clustered mutations in the region of DICER1 which encode the RNase IIIb domain in four samples. Based on these findings, the OvCaRe team sequenced the same region of DICER1 in additional ovarian tumors, and tested for the effect of the mutations on the enzymatic activity of DICER1.

Recurrent somatic (i.e., lifetime-acquired) DICER1 mutations in the RNase IIIb domain were identified in 30 of 102 nonepithelial ovarian tumors (29%), including 4 tumors which also possessed germline (i.e., inherited) DICER1 mutations. The highest frequency of somatic DICER1 mutations occurred in Sertoli–Leydig cell tumors (26 of 43, or 60%). Notably, the mutant DICER1 proteins identified in the samples possessed reduced RNase IIIb activity, but retained RNase IIIa activity.

The Canadian researchers also performed additional tumor testing and detected the DICER1 mutations in 1 of 14 nonseminomatous testicular germ-cell tumors, 2 of 5 embryonal rhabdomyosarcomas, and in 1 of 266 epithelial ovarian and endometrial carcinomas.

The groundbreaking nature of this discovery is reflected in the fact that the DICER1 “hotspot” mutations are not present in the 1000 Genomes Project data or the public data repository of The Cancer Genome Atlas consortium. To date, no recurrent DICER1 mutations have been reported in the mutation database of the Catalogue of Somatic Mutations in Cancer (COSMIC), in which 4 of 938 reported cancers possess somatic mutations but none in the RNase IIIb domain hot spots or RNase IIIa equivalents. Moreover, the Canadian researchers note that the newly-discovered DICER1 mutations were not observed in any of the more than 1000 cancer sequencing libraries which were studied.

Based upon the foregoing , the researchers concluded that somatic missense mutations affecting the RNase IIIb domain of DICER1 occur in a range of nonepithelial ovarian tumors, and possibly other cancers. Furthermore, the DICER1 mutations appear to be common in Sertoli-Leydig ovarian tumors (which are a subtype of nonepithelial, sex cord-stromal ovarian tumors). The researchers believe that the recurrent DICER1 mutations identified implicate a novel defect in miRNA processing which does not entirely destroy DICER1 functionality, but alters it.

Accordingly, the Canadian researchers suggest that the newly-discovered DICER1 mutations may represent an oncogenic event within the specific context of nonepithelial ovarian tumors, rather than a permissive event in tumor onset (as may be expected for loss of function in a tumor suppressor gene). The researchers note that DICER1 expression in tumors possessing the hotspot DICER1 somatic mutations argues against a role for DICER1 as a classic tumor suppressor gene. They further explain that the localized and focal pattern of the identified DICER1 mutations is typical of dominantly acting oncogenes, like KRAS and BRAF.

In sum, the Canadian researchers believe that the recurrent and focal nature of the DICER1 mutations and their restriction to nonepithelial ovarian tumors suggest a common oncogenic mechanism associated with a specifically altered DICER1 function that is selected during tumor development in specific cell types.

The Canadian study was supported through funding by Canadian Institutes for Health Research, Terry Fox Foundation, BC Cancer Foundation, VGH & UBC Hospital Foundation, Michael Smith Foundation for Health Research, and Genome BC.

Expert Commentary

DICER is of great interest to cancer researchers” said Dr. Huntsman, who also holds the Dr. Chew Wei Memorial Professorship in the departments of Obstetrics and Gynecology and Pathology and Laboratory Medicine at UBC. “There have been nearly 1,300 published studies about it in the last 10 years, but until now, it has not been known how the gene functions in relation to cancer.”

“This discovery shows researchers that these mutations change the function of DICER so that it participates directly in the initiation of cancer, but not in a typical ‘on-off’ fashion,” says Dr. Morin who is also assistant professor in the department of Medical Genetics at UBC. “DICER can be viewed as the conductor for an orchestra of functions critical for the development and behavior of normal cells. The mutations we discovered do not totally destroy the function of DICER rather they warp it—the orchestra is still there but the conductor is drunk.”

This finding is the third of a series of papers published recently in the New England Journal of Medicine (NEJM) in which the OvCaRe team used new genomic technologies to unlock the molecular basis of poorly understood types of ovarian cancer. The first finding, published in the NEJM in 2009, identified mutations in the FOXL2 (forkhead box L2) gene as the molecular basis of adult granulosa cell ovarian cancer tumors. The second finding, published in the NEJM in 2010, determined that approximately one-half of clear-cell ovarian cancers and one-third of endometrioid ovarian cancers possess ARID1A  (AT rich interactive domain 1A) gene mutations.

The DICER gene mutation breakthrough discovery is particularly pivotal because it could lead to solutions for treatment of more common cancers.

“Studying rare tumors not only is important for the patients and families who suffer from them but also provides unique opportunities to make discoveries critical to more common cancers – both in terms of personalized medicine, but also in applying what we learn from how we manage rare diseases to more common and prevalent cancers,” said Dr. Huntsman “The discovery of the DICER mutation in this varied group of rare tumors is the equivalent of finding not the needle in the haystack, but rather the same needle in many haystacks.”

Dr. Phillip A. Sharp, Professor, Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology; Co-winner of the 1993 Nobel Prize in Physiology and Medicine

“This breakthrough will be of interest to both the clinical and the fundamental science communities,” says Dr. Phillip A. Sharp, Professor, Koch Institute for Integrative Cancer Research at the Massachusetts Institute of Technology, and co-winner of the 1993 Nobel Prize in Physiology or Medicine for the discovery that genes are not contiguous strings but contain introns, and that the splicing of mRNA to delete those introns can occur in different ways, thereby yielding different proteins from the same DNA sequence. “Huntsman, Morin and colleagues’ very exciting discovery of specific mutations in DICER, a factor essential for syntheses of small regulatory RNAs in ovarian and other human tumors, could lead to new approaches to treatment.”

The Canadian OvCaRe research team is now working to determine the frequency and role of DICER mutations in other types of cancers. The research team is also expanding its collaboration to discover whether mutant DICER and the pathways it controls can be modulated to treat the rare cancers in which the mutations were discovered and more common cancers.

The Michael Smith Genome Sciences Centre (Michael Smith GSC), located at the BC Cancer agency, played a key role in this discovery. By way of background, Dr. Michael Smith was a co-winner of the 1993 Nobel Prize in Chemistry for his development of oligonucleotide-based site-directed mutagenesis, a technique which allows the DNA sequence of any gene to be altered in a designated manner. His technique created a groundbreaking method for studying complex protein functions, the basis underlying a protein’s three-dimensional structure, and a protein’s interaction with other molecules inside the cell.

A decision was made more than 10 years ago, championed by Drs. Michael Smith, Victor Ling, and others to create and locate the Michael Smith GSC within the BC Cancer Agency and in close proximity to Vancouver General Hospital (VGH). The chosen location for this critical facility provided the multidisciplinary cancer research teams in Vancouver with access to state-of-the-art technologies.

“We are one of less than five places in the world doing this type of work successfully. This discovery is one of a series of recent landmark findings from Vancouver that are reshaping our understanding of many cancers,” says Dr. Huntsman. “Since my arrival in Vancouver 20 years ago I have never before sensed such a strong feeling of communal pride and excitement within our research community. Our next task is to bring the discoveries into the clinic.”

About the Ovarian Cancer Research Program of British Columbia (OvCaRe)

OvCaRe is a multidisciplinary research program involving clinicians and research scientists in gynecology, pathology, and medical oncology at VGH and BC Cancer Agency. OvCaRe is a unique collaboration between the BC Cancer Agency, Vancouver Coastal Health Research Institute, and UBC. The OvCaRe team is considered a leader in ovarian cancer research which is breaking new ground in better identifying, understanding, and treating this disease. The OvCaRe seminal paper in PLoS (Public Library of Science), which addresses ovarian cancer as a group of distinct diseases, has been embraced by the global research community who has adopted the BC approach to ovarian cancer research. To learn more, visit www.ovcare.ca.

About the Michael Smith Genome Sciences Centre

Canada’s Michael Smith Genome Sciences Centre is an internationally recognized state-of-the-art facility applying genomics and bioinformatics tools and technologies to cancer research. Led by Dr. Marco Marra, the Michael Smith GSC is one of ten leading genomic research centres in the world and the only one of its kind in the world integrated into a cancer facility. With a primary focus on cancer genomics research, its scientists have been involved in many world-class groundbreaking discoveries over the past decade. To learn more, visit www.bcgsc.ca.

About the Vancouver Coastal Health Research Institute

Vancouver Coastal Health Research Institute is the research body of Vancouver Coastal Health Authority, which includes BC’s largest academic and teaching health sciences centres: Vancouver General Hospital, UBC Hospital, and GF Strong Rehabilitation Centre. The institute is academically affiliated with the UBC Faculty of Medicine, and is one of Canada’s top-funded research centres, with $82.4 million in research funding for 2009/2010. To learn more, visit www.vchri.ca.

About the British Columbia Cancer Agency

The BC Cancer Agency, an agency of the Provincial Health Services Authority, is committed to reducing the incidence of cancer, reducing the mortality from cancer, and improving the quality of life of those living with cancer. It provides a comprehensive cancer control program for the people of British Columbia by working with community partners to deliver a range of oncology services, including prevention, early detection, diagnosis and treatment, research, education, supportive care, rehabilitation and palliative care. To learn more, visit www.bccancer.ca.

About the University of British Columbia

The University of British Columbia is one of North America’s largest public research and teaching institutions, and one of only two Canadian institutions consistently ranked among the world’s 40 best universities. Surrounded by the beauty of the Canadian West, it is a place that inspires bold, new ways of thinking that have helped make it a national leader in areas as diverse as community service learning, sustainability, and research commercialization. UBC offers more than 55,000 students a range of innovative programs and attracts $550 million per year in research funding from government, non-profit organizations, and industry through 7,000 grants. To learn more, visit www.ubc.ca.

References

1/Morin G, Hunstman, DG et al.  Recurrent Somatic DICER1 Mutations in Nonepithelial Ovarian CancersNEJM, published online December 21, 2011 (10.1056/NEJMoa1102903).

2/The Canadian investigators describe the operation of the RNAi pathway with respect to miRNA biogenesis as follows:

“MicroRNAs (miRNAs) are a functional class of noncoding RNA molecules that regulate translation and degradation of messenger RNA. MiRNA transcripts are processed from hairpin pre-miRNA precursors into short miRNA:  miRNA* duplexes consisting of the miRNA targeting strand and the imperfectly complementary miRNA* strand (star strand, or inert carrier strand) by Dicer, an endoribonuclease with two RNase III–like domains. The RNase IIIb domain cuts the miRNA strand, whereas the RNase IIIa domain cleaves the miRNA* strand. The resultant RNA duplex is loaded into the RNA-induced silencing complex (RISC) containing an Argonaute protein. The miRNA* strand is then removed, leaving the miRNA strand, which targets messenger RNAs (mRNAs) for degradation or interacts with the translation initiation complex to inhibit and destabilize translation of the targeted messenger RNAs.” [footnote citations omitted]

3/Merritt WM, et al. Dicer, Drosha, and outcomes in patients with ovarian cancer. N Engl J Med. 2008 Dec 18;359(25):2641-50. Erratum in: N Engl J Med. 2010 Nov 4;363(19):1877. PubMed PMID: 19092150; PubMed Central PMCID: PMC2710981.

Sources:

2011 ASCO: Additional Phase III Study Data Support the Potential Role of Avastin in Newly-Diagnosed & Recurrent Ovarian Cancer

Positive results from two bevacizumab (Avastin®) phase III clinical studies were presented at the 2011 American Society of Clinical Oncology Annual Meeting on June 4. The data reported add to the growing body of evidence in support of bevacizumab use to treat recurrent and newly-diagnosed ovarian cancer.

Positive results from two bevacizumab (Avastin®) phase III clinical studies were presented at the 2011 American Society of Clinical Oncology Annual Meeting on June 4. The data reported add to the growing body of evidence in support of bevacizumab use to treat recurrent and newly-diagnosed ovarian cancer.

About Bevacizumab (Avastin®)

A diagram illustrating the role of the VEGF protein in the formation of new blood vessels that support tumor growth. Click on the picture above to view a video regarding the mechanism of action with respect to bevacizumab (Avastin®). (Photo: Genentech)

Angiogenesis” refers to the process of new blood vessel formation. When tissues need more oxygen, they release molecules that encourage blood vessel growth. Angiogenesis is a normal and vital process in human growth and development, as well as in wound healing. Unfortunately, cancer tumors also utilize this same process to enhance their own blood supply in order to nourish their aberrant growth.

Ovarian cancer is associated with high concentrations of vascular endothelial growth factor (VEGF), a protein associated with tumor growth and spread. Studies have shown a correlation between a high concentration of VEGF and ascites  (excess fluid in the body cavity) development, disease worsening, and a poorer prognosis in women with ovarian cancer.[1-2]

Bevacizumab is a humanized monoclonal antibody designed to specifically bind to the VEGF protein, which plays an important role throughout the lifecycle of the tumor to develop and maintain blood vessels through angiogenesis. The drug interferes with the tumor blood supply by directly binding to the VEGF protein to prevent interactions with receptors on blood vessel cells. The tumor blood supply is thought to be critical to a tumor’s ability to grow and spread in the body (metastasize).

Bevacizumab is the first U.S. Food and Drug Administration (FDA) approved therapy designed to inhibit angiogenesis. Although FDA-approved for several forms of cancer, bevacizumab is not yet approved for the treatment of ovarian cancer. Patients treated with bevacizumab may experience side effects. In past clinical trials, some people treated with bevacizumab experienced serious and sometimes fatal side effects, related to gastrointestinal (GI) perforation, surgery and wound healing, and severe bleeding. For more information, review the Avastin BOXED WARNINGS and Additional Important Safety Information.

OCEANS Phase III Clinical Study: Women with Recurrent Platinum Sensitive Ovarian Cancer Experience 78% Response Rate & 52% Reduction In Disease Progression Risk

  • About the OCEANS Study

“OCEANS” is a multicenter, randomized, double-blind, placebo-controlled Phase III study in 484 women with platinum drug-sensitive recurrent ovarian, primary peritoneal or fallopian tube cancer.[3] Women in the OCEANS study received no more than one treatment regimen prior to study enrollment.  The OCEANS study randomized enrolled women to one of two clinical study arms:

Arm A: Intravenous carboplatin (area under the curve (AUC) 4; Day 1) + gemcitabine  (1,000 mg/m2; Day 1 & 8; brand name: Gemzar®) + placebo (Day 1) every 21 days x 6 cycles, followed by placebo maintenance every 21 days, until disease progression or unacceptable toxicity occurred.

Arm B: Carboplatin + gemcitabine + bevacizumab (15 mg/kg; Day 1) every 21 days x 6 cycles, followed by single agent bevacizumab maintenance every 21 days, until disease progression or unacceptable toxicity occurred.

The primary endpoint of the OCEANS study was progression free survival. The secondary endpoints of the study included overall survival, objective response, duration of response and safety profile.

  • OCEANS Study Data

Carol Aghajanian, M.D. speaks during the Oral Abstract Session: Gynecologic Cancer at the American Society of Clinical Oncology Annual Meeting on Saturday June 4, 2011. (Photo: ASCO/GMG/Silas Crews 2011)

Carol Aghajanian, M.D., chief of the gynecologic medical oncology service at Memorial Sloan-Kettering Cancer Center, presented the data from the OCEANS study comparing efficacy and safety of chemotherapy and antiangiogenic therapy in platinum drug-sensitive recurrent ovarian cancer.

Two hundred forty-two women were allocated to each study arm and the median follow-up period was 24 months. Patient characteristics were well-matched in the two treatment groups with regard to age (median age ~60), race (~91% white), performance status (~75%, PS = 0), histologic subtype (~80% serous), cytoreductive surgery (~11%), and platinum-free interval (defined as the time between finishing front-line platinum-based therapy and starting second-line chemotherapy) of more than 12 months (~60%). The study stratification variables were platinum-free interval (6 to 12 months vs. more than 12) and cytoreductive surgery for recurrent disease (yes vs. no).

The median number of chemotherapy cycles was six for each group, and a median of 11 cycles of bevacizumab or placebo was given. At least one-third of the patients received more than six cycles of carboplatin and gemcitabine, although slightly more of the placebo-treated group continued chemotherapy beyond six cycles.

Progression-free survival was significantly longer for women given bevacizumab (12.4 months vs. 8.4 months in the placebo-treated group (hazard ratio [HR]: 0.484; 95% confidence interval (CI) [0.388, 0.605]; p < 0.0001). These results were corroborated by the analyses of an independent review committee. Analyses according to platinum-free interval, cytoreductive surgery, age, and baseline performance status indicate a consistent benefit in all subgroups.

Objective response rate increased by 21.1% (p < 0.0001), from 57.4% in the placebo group to 78.5% in the bevacizumab treated group; duration of response increased from a median of 7.4 months to 10.4 months, respectively (HR: 0.534; 95% CI [0.408, 0.698]; p < 0.0001). Overall survival data are still premature, with median survival of 29.9 months in the placebo group and 35.5 months in the bevacizumab treatment group.

Sixty-five percent of the patients in the placebo group were withdrawn from the protocol due to disease progression, compared with only 41% of the treatment group, but 23% of the discontinuations in the bevacizumab group were due to adverse events, compared with only 5% in the placebo group. Much of this increase was due to grade 3 (or worse) adverse events; specifically hypertension and proteinuria associated with bevacizumab therapy. Overall, the safety profile of bevacizumab was consistent with past trials.

  • OCEANS Study Commentary

Dr. Aghajanian concluded that the OCEANS study results demonstrate a statistically significant and clinically relevant benefit when bevacizumab is added to carboplatin and gemcitabine. Aghajanian stated that this regimen should be considered a new option for the treatment of recurrent, platinum drug-sensitive ovarian cancer. As expected, the rate of adverse events was higher among patients who received bevacizumab, explained Dr. Aghajanian. “Hypertension and proteinuria were increased, but febrile neutropenia was the same in both arms.” “The safety data are reassuring and consistent with the known bevacizumab side-effect profile, and there were no new safety signals,” said Dr. Aghajanian.

“In advanced ovarian cancer, just as in advanced breast cancer, there is often an opportunity to intervene with different lines of chemotherapy,” said Andrew Seidman, M.D., attending physician for the breast cancer medicine service at Memorial Sloan-Kettering Cancer Center and professor of medicine at Weill Medical College of Cornell University. “There are many chapters in the story, so to speak,” said Dr. Seidman, who moderated a press briefing held in advance of the presentation. “We want to prolong each and every chapter in the disease, and make the story longer and ultimately improve survival. These trials results are certainly an important step in that direction.”

“Women with recurrent ovarian cancer need new treatment options, and it is therefore an important advance to halve the risk of disease progression in this incurable cancer,” said Hal Barron, M.D., chief medical officer and head of Roche Holdings Global Product Development. “These data add to the growing body of evidence supporting Avastin’s potential role in this disease, which includes two previously presented Phase III clinical trials [Gynecologic Oncology Group (GOG)-218 [4] & ICON7] in women with newly diagnosed ovarian cancer.”

In his discussion of the study, Anil K. Sood, M.D., professor and director of the Blanton-Davis Ovarian Cancer Research Program in the Departments of Gynecologic Oncology and Cancer Biology at the University of Texas M.D. Anderson Cancer Center, suggested that further understanding of the timing and dosing of bevacizumab should be pursued in light of (i) its great financial cost, and (ii) reports that inhibition of angiogenesis in animal models reduces primary cancer tumor growth, but accelerates invasion and metastasis — unintended consequences that might be linked to the failure of bevacizumab to extend overall survival in most clinical trials.

ICON7 Phase III Clinical Study:  Newly-Diagnosed Women with High-Risk Ovarian Cancer Experience 36% Reduction in Risk of Death

Gunnar Kristensen M.D., Ph.D. speaks during the Women's Cancers Press Briefing at the American Society of Clinical Oncology Annual Meeting on June 4, 2011. (Photo: ASCO/GMG/Scott Morgan 2011)

ICON7 was designed to investigate safety and efficacy of adding bevacizumab to standard chemotherapy in women with newly diagnosed ovarian cancer. [5] Gunnar Kristensen, M.D, Ph.D., senior consultant in the Department for Gynecologic Oncology of the Norwegian Radium Hospital located in Oslo, reported the Phase III clinical study results.

  • About the ICON7 Study

From December 2006 to February 2009, 1,528 women were randomized from 263 centers in 7 Gynecologic Cancer InterGroups. Eligible women with high-risk early FIGO (Federation of International Gynecology and Obstetrics) stage I or IIa (grade 3 or clear cell histology), capped ≤10%) or advanced (stage IIb-IV) epithelial ovarian, primary peritoneal or fallopian tube cancer were randomizsed (1:1) to one of two study arms:

Arm A: 6 cycles of 3 weekly chemotherapy (carboplatin AUC 5 or 6 and paclitaxel 175mg/m2) alone;  or

Arm B: Same chemotherapy as in Arm A, given concurrently with bevacizumab (7.5mg/kg) for 5 or 6 cycles, followed by continued 3-weekly single-agent bevacizumab maintenance therapy for 12 additional cycles (up to 12 months) or until disease progression (whichever event occurs first).

The baseline patient characteristics were balanced between both study arms: median age (57 years); ECOG Performance Status 0-1 (47%); high-risk early-stage disease (9%); poor prognosis patients (30%); histology (69% serous, 8% endometrioid, 8% clear cell).

  • Updated ICON7 Progression Free Survival Data

Data from the ICON7 study were presented for the first time at the 2010 European Society of Medical Oncology (ESMO) Congress. As reported at ESMO, chemotherapy-naïve ovarian cancer patients who received bevacizumab in combination with standard chemotherapy, and then continued with single agent bevacizumab maintenance therapy, experienced approximately 27% improvement (18.3 months versus 16 months) in the likelihood of living longer without the disease worsening (i.e., progression-free survival) compared to those women who received only chemotherapy (hazard ratio = 0.79, p=<0.0010), which corresponds to a 21% reduction in risk of cancer progression or death. The ICON7 data presented at ESMO was based upon mature progression-free survival results.

The updated ICON7 progression-free survival data presented at the ASCO annual meeting were consistent with the data reported last year at ESMO. In the updated analysis, women assigned to the bevacizumab arm experienced longer progression-free survival than those in the control group (19.8 months vs 17.4 months; HR, 0.87; p =.039). “There is a substantial prolongation of time to progression,” said Dr. Kristensen, adding that the gain was 2.4 months.

  • ICON7 Overall Survival Data Immature; But Clear Benefit To Women With “Poor Prognosis.” 

At a median follow-up of 28 months, there were fewer deaths among women who received bevacizumab than among those who received standard chemotherapy (178 vs 200). Although this represents a 15% overall reduction in mortality risk, the difference did not reach statistical significance (hazard ratio [HR], 0.85; P = .11). The final analyses for overall survival will be performed when 715 patient deaths have occurred. The current analysis was conducted because an interim analysis with at least 365 deaths was requested by the FDA and the European Medicines Agency for licensing consideration.

Although the overall survival data is not mature, a subgroup analysis of women with a “poor prognosis” (defined as FIGO stage III patients debulked to >1.0cm of visible diease or FIGO stage IV with debulking) was performed. Within this subgroup, there were 79 deaths within the bevacizumab arm and 109 deaths in the control arm. Based on this data, there was a 36% reduction in the risk of death (HR=0.64, 95% CI=0.48 to 0.85, p=0.0022 with p=0.015 for test for interaction (treatment/risk group)) among the poor prognosis subgroup.  This result was statistically significant. “We have previously shown that [the high-risk] group has a greater benefit from bevacizumab than the other patients,” said Dr. Kristensen. “For this group, there is a very clear gain for overall survival.”

  • ICON7 Study Commentary

“We conclude that the addition of concurrent and continued bevacizumab for 12 months does improve progression-free survival,” said Dr. Kristensen.  Kristensen also noted that, on the basis of an interim analysis involving approximately 53% of the number of deaths needed for the final analysis, there is an overall trend for improvement in overall survival.

“In this study, we see the ability of antiangiogenic therapy to delay the progression of ovarian cancer, this time in the first-line setting,” said Andrew Seidman, M.D. He added that previous studies have demonstrated the efficacy of bevacizumab in ovarian cancer. “These lend support to a potential role for bevacizumab as the first biologic agent to be used in this disease,” said Seidman, who moderated a press briefing during which study highlights were presented.

There are many strengths in a study like this, in that it addresses questions about the role of anti-VEGF therapies in this setting, said Anil Sood, M.D., who served as a discussant for this paper. “The randomized design is obviously a major strength.”

However, there are potential issues to examine, explained Dr. Sood. “One is the role of bevacizumab in the combination setting, compared with the maintenance setting.”

“How useful is bevacizumab in the combination setting up front? Is the real role for bevacizumab in the maintenance setting following initial chemotherapy,” he asked.

The issue of bevacizumab dosing was also raised by Dr. Sood. “One of the questions is whether higher doses are needed,” he said. “There are data emerging from other studies showing that lower doses are as efficacious, if not more so.”

References:

1/Rudlowski C, Pickart AK, Fuhljahn C, et. al. Prognostic significance of vascular endothelial growth factor expression in ovarian cancer patients: a long-term follow-up. Int J Gynecol Cancer. 2006 Jan-Feb;16 Suppl 1:183-9. PubMed PMID: 16515588.

2/Cooper BC, Ritchie JM, Broghammer CL, et. al. Preoperative serum vascular endothelial growth factor levels: significance in ovarian cancer. Clin Cancer Res. 2002 Oct;8(10):3193-7.  PMID: 12374688

3/Aghajanian C, Finkler NJ, Rutherford T, et. alOCEANS: A randomized, double-blinded, placebo-controlled phase III trial of chemotherapy with or without bevacizumab (BEV) in patients with platinum-sensitive recurrent epithelial ovarian (EOC), primary peritoneal (PPC), or fallopian tube cancer (FTC)J Clin Oncol 29: 2011 (suppl; abstr LBA5007)[2011 American Society of Clinical Oncology Annual Meeting].

4/ Burger RA, Brady MF, Bookman MA, et. alPhase III trial of bevacizumab in the primary treatment of advanced epithelial ovarian cancer (EOC), primary peritoneal cancer (PPC), or fallopian tube cancer (FTC): a Gynecologic Oncology Group study [GOG 218 Abstract]J Clin Oncol 28:18s, 2010 (suppl; abstr LBA1).

5/Kristensen G, Perren T, Qian W., et. alResult of interim analysis of overall survival in the GCIG ICON7 phase III randomized trial of bevacizumab in women with newly diagnosed ovarian cancerJ Clin Oncol 29: 2011 (suppl; abstr LBA5006) [2011 American Society of Clinical Oncology Annual Meeting].

Additional Sources & Helpful Information:

Bevacizumab (Avastin®) Clinical Trial Information

Related WORD of HOPE Ovarian Cancer Podcast™

Related Libby’s H*O*P*E*™ Postings

Related Libby’s H*O*P*E*™ Videos

  • To view videos regarding bevacizumab (Avastin®), click here.


2010-2011 U.S. News & World Report “Best Hospitals” List

This week, U.S. News & World Report issued its 2010-2011 rankings of the best U.S. hospitals for adults. The University of Texas, M.D. Anderson Cancer Center is rated #1 in cancer treatment, and Johns Hopkins is rated #1 in gynecology and #1 overall based upon all medical specialties.

If you would like more information regarding the 2010-2011 U.S. News & World Report best U.S. hospital rankings, click here. To better understand how U.S. News & World Report ranked the hospitals in each specialty, read Best Hospitals 2010-11: The Methodology, written by U.S. News & World Report’s Avery Comarow.  If you would like to review the current U.S. News & World Report America’s Best Children’s Hospitals list, click here.

Top 10 U.S. Hospitals: Cancer

Top 10 U.S. Hospitals: Gynecology

Top 10 U.S. Hospitals (highest scores in at least six medical specialties)
1. Univ. of Texas M.D. Anderson Cancer Center, Houston, Texas Johns Hopkins Hospital, Baltimore, Maryland Johns Hopkins Hospital, Baltimore, Maryland
2. Memorial Sloan-Kettering Cancer Center, New York, New York Mayo Clinic, Rochester, Minnesota Mayo Clinic, Rochester, Minnesota
3. Mayo Clinic, Rochester, Minnesota Brigham and Women’s Hospital,Boston, Massachusetts Massachusetts General Hospital, Boston, Massachusetts
4. Johns Hopkins Hospital, Baltimore, Maryland Cleveland Clinic, Cleveland, OH Cleveland Clinic, Cleveland, Ohio
5. University of Washington Medical Center, Seattle, Washington Massachusetts General Hospital, Boston, Massachusetts Ronald Reagan UCLA Medical Center, Los Angeles
6. Dana-Farber Cancer Institute, Boston, Massachusetts Magee-Womens Hospital of Univ. of Pittsburgh Medical Center, Pittsburgh, Pennsylvania New York-Presbyterian Univ. Hospital of Columbia & Cornell, New York, New York
7. Massachusetts General Hospital, Boston, Massachusetts Duke University Medical Center, Durham, North Carolina Univ. of California, San Francisco (UCSF) Medical Center
8. Univ. of California, San Francisco (UCSF) Medical Center Univ. of California, San Francisco (UCSF) Medical Center Barnes-Jewish Hospital/Washington University, St. Louis
9. Cleveland Clinic, Cleveland, Ohio New York-Presbyterian Univ. Hospital of Columbia & Cornell, New York, New York Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania
10. Ronald Reagan UCLA Medical Center, Los Angeles Memorial Sloan-Kettering Cancer Center, New York, New York Duke University Medical Center, Durham, North Carolina

MAGP2 Gene Expression Signature: A Potential Ovarian Cancer Personalized Treatment Target

A multi-institutional study has identified a potential personalized treatment target for the most common form of ovarian cancer. In the December 8 issue of Cancer Cell, the research team describes finding that a gene called MAGP2 – not previously associated with any type of cancer – was overexpressed in papillary serous ovarian tumors of patients who died more quickly. They also found evidence suggesting possible mechanisms by which MAGP2 may promote tumor growth.

A multi-institutional study has identified a potential personalized treatment target for the most common form of ovarian cancer. In the December 8 issue of Cancer Cell, the research team describes finding that a gene called MAGP2 (microfibril-associated glycoprotein 2) – not previously associated with any type of cancer – was overexpressed in papillary serous ovarian tumors of patients who died more quickly. They also found evidence suggesting possible mechanisms by which MAGP2 may promote tumor growth.

Michael Birrer, MD, Ph.D., Professor, Department of Medicine, Harvard Medical School; Director GYN/Medical Oncology, Medicine, Massachusetts General Hospital

“Ovarian cancer is typically diagnosed at an advanced stage when it is incurable, and the same treatments have been used for virtually all patients,” says Michael Birrer, MD, PhD, director of medical gynecologic oncology in the Massachusetts General Hospital (MGH) Cancer Center, and the study’s corresponding author. “Previous research from my lab indicated that different types and grades of ovarian tumors should be treated differently, and this paper now shows that even papillary serous tumors have differences that impact patient prognosis.” Birrer was with the National Institutes of Health when this study began but later joined the MGH Cancer Center.

The fifth most common malignancy among U.S. women, ovarian cancer is expected to cause approximately 15,000 deaths during 2009. Accounting for 60 percent of ovarian cancers, papillary serous tumors are typically diagnosed after spreading beyond the ovaries. The tumors typically return after initial treatment with surgery and chemotherapy, but while some patients die a few months after diagnosis, others may survive five years or longer while receiving treatment.

To search for genes expressed at different levels in ovarian cancer patients with different survival histories, which could be targets for new treatments, the researchers conducted whole-genome profiling of tissue samples that had been microdissected – reducing the presence of non-tumor cells – from 53 advanced papillary serous ovarian cancer tumors. Of 16 genes that appeared to have tumor-associated expression levels, MAGP2 had the strongest correlation with reduced patient survival.

Further analysis confirmed that MAGP2 expression was elevated in another group of malignant ovarian cancer tumors but not in normal tissue. MAGP2 gene expression was also reduced in patients whose tumors responded to chemotherapy. Recombinant expression of MAGP2 in samples of the endothelial cells that line blood vessels caused the cells to migrate and invade normal tissue.  In addition, MAGP2 gene overexpression increased microvessel density — a measurement used to determine the extent of tumor angiogenesis. The latter two observations suggest a potential role for MAGP2 gene overexpression in the growth of an ovarian cancer tumor’s blood supply.

“By confirming that different ovarian tumors have distinctive gene signatures that can predict patient prognosis, this study marks the beginning of individualized care for ovarian cancer,” says Birrer, a professor of Medicine at Harvard Medical School. “MAGP2 and the biochemical pathways it contributes to are definitely targets for new types of therapies, and we plan to pursue several strategies to interfere with tumor-associated pathways. But first we need to validate these findings in samples from patients treated in clinical trials.”

About The Study

Co-lead authors of the Cancer Cell paper are Samuel Mok, M.D., M.D. Anderson Cancer Center, and Tomas Bonome, National Cancer Institute (NCI). Additional co-authors are Kwong-Kowk Wong, M.D. Anderson; Vinod Vathipadiekal, Aaron Bell, Howard Donninger, Laurent Ozbun, Goli Samimi, John Brady, Mike Randonovich, Cindy Pise-Masison, and Carl Barrett, NCI; Michael Johnson, Dong-Choon Park, William Welch and Ross Berkowitz, Brigham and Women’s Hospital; Ke Hao and Wing Wong, Harvard School of Public Health; and Daniel Yip, University of South Florida. The study was supported by grants from the National Institutes of Health, the Ovarian Cancer Research Fund and the National Cancer Institute.

About Massachusetts General Hospital

Massachusetts General Hospital, established in 1811, is the original and largest teaching hospital of Harvard Medical School. The MGH conducts the largest hospital-based research program in the United States, with an annual research budget of more than $600 million and major research centers in AIDS, cardiovascular research, cancer, computational and integrative biology, cutaneous biology, human genetics, medical imaging, neurodegenerative disorders, regenerative medicine, systems biology, transplantation biology and photomedicine.

Sources:

M.D. Anderson Study Predicts Dramatic Growth in Cancer Rates Among U.S. Elderly, Minorities

” … Over the next 20 years, the number of new cancer cases diagnosed annually in the United States will increase by 45 percent, from 1.6 million in 2010 to 2.3 million in 2030, with a dramatic spike in incidence predicted in the elderly and minority populations, according to research from The University of Texas M. D. Anderson Cancer Center. …Given these statistics, the role of screening and prevention strategies becomes all the more vital and should be strongly encouraged, said [Ben] Smith [M.D.]. … These findings also highlight two issues that must be addressed simultaneously: clinical trial participation and the increasing cost of cancer care. Historically, both older adults and minorities have been under-represented in such studies, and, therefore, vulnerable to sub-optimal cancer treatment. Simultaneously, over the past decade in particular, the cost of cancer care is growing at a rate that’s not sustainable. …”

“Research underscores impact on health care system, importance of screenings, prevention strategies, inclusive clinical trials

Cancer Newsline Podcast
M. D. Anderson audio player (click & play)
Dramatic Growth in Cancer Rates Among Elderly, Minorities

Over the next 20 years, the number of new cancer cases diagnosed annually in the United States will increase by 45 percent, from 1.6 million in 2010 to 2.3 million in 2030, with a dramatic spike in incidence predicted in the elderly and minority populations, according to research from The University of Texas M. D. Anderson Cancer Center.

The study, published online today in Journal of Clinical Oncology, is the first to determine such specific long-term cancer incidence projections. It predicts a 67 percent increase in the number of adults age-65-or-older diagnosed with cancer, from 1 million in 2010 to 1.6 million in 2030. In non-white individuals over the same 20-year span, the incidence is expected to increase by 100 percent, from 330,000 to 660,000.

Ben Smith, M.D., Adjunct Assistant Professor, Department of Radiation Oncology, The University of Texas M.D. Anderson Center

Ben Smith, M.D., Adjunct Assistant Professor, Department of Radiation Oncology, The University of Texas M.D. Anderson Cancer Center

According to Ben Smith, M.D., adjunct assistant professor in M. D. Anderson’s Department of Radiation Oncology, the study underscores cancer’s growing stress on the U.S. health care system.

‘In 2030, 70 percent of all cancers will be diagnosed in the elderly and 28 percent in minorities, and the number of older adults diagnosed with cancer will be the same as the total number of Americans diagnosed with cancer in 2010,’ said Smith, the study’s senior author. ‘Also alarming is that a number of the types of cancers that are expected to increase, such as liver, stomach and pancreas, still have tremendously high mortality rates.’

Unless specific prevention and/or treatment strategies are discovered, cancer death rates also will increase dramatically, said Smith, who is currently on active military duty and is stationed at Lackland Air Force Base.

To conduct their research, Smith and his team accessed the United States Census Bureau statistics, updated in 2008 to project population growth through 2050, and the National Cancer Institute’s Surveillance, Epidemiology and End Results (SEER) registry, the premier population-based cancer registry representing 26 percent of the country’s population. Cancer incidence rates were calculated by multiplying the age, sex, race and origin-specific population projections by the age, sex, race and origin-specific cancer incidence rates.

The researchers found that from 2010 to 2030, the population is expected to grow by 19 percent (from 305 to 365 million). The total number of cancer cases will increase by 45 percent (from 1.6 to 2.3 million), with a 67 percent increase in cancer incidence in older Americans (1 to 1.6 million), compared to an 11 percent increase in those under the age of 65 (.63 to .67 million).

With respect to race, a 100 percent increase in cancer is expected for minorities (.33 to .66 million); in contrast, in white Americans, a 31 percent increase is anticipated (1.3 to 1.7 million). The rates of cancer in blacks, American Indian-Alaska Native, multi-racial, Asian-Pacific Islanders and Hispanics will increase by 64 percent, 76 percent, 101 percent, 132 percent and 142 percent, respectively.

Regarding disease-specific findings, Smith and his team found that the leading cancer sites are expected to remain constant – breast, prostate, colon and lung. However, cancer sites with the greatest increase in incidence expected are: stomach (67 percent); liver (59 percent); myeloma (57 percent); pancreas (55 percent); and bladder (54 percent).

Given these statistics, the role of screening and prevention strategies becomes all the more vital and should be strongly encouraged, said Smith. In the study, Smith and his team site [sic]: vaccinations for hepatitis B and HPV; the chemoprevention agents tamoxifen and raloxifene; interventions for tobacco and alcohol; and removal of pre-malignant lesions, such as colon polyps.

These findings also highlight two issues that must be addressed simultaneously: clinical trial participation and the increasing cost of cancer care. Historically, both older adults and minorities have been under-represented in such studies, and, therefore, vulnerable to sub-optimal cancer treatment. Simultaneously, over the past decade in particular, the cost of cancer care is growing at a rate that’s not sustainable.

‘The fact that these two groups have been under-represented in clinical research participation, yet their incidence of cancer is growing so rapidly, reflects the need for therapeutic trials to be more inclusive and address issues that are particularly relevant to both populations,’ said Smith. ‘In addition, as we design clinical trials, we need to seek not only the treatment that will prolong survival, but prolong survival at a reasonable cost to patients. These are two issues that oncologists need to be much more concerned about and attuned to.’

Another issue that needs to be addressed is the shortage of health care professionals predicted. For example, according to a workforce assessment by American Society for Clinical Oncology (ASCO), the shortage of medical oncologists will impact the health care system by 2020. Smith said ASCO and other professional medical organizations beyond oncology are aware of the problem, and are actively engaged in efforts to try and grow the number of physicians, as well as encourage the careers of nurse practitioners and physician assistants who are part of the continuum of care, to best accommodate the increase in demand forecasted.

‘There’s no doubt the increasing incidence of cancer is a very important societal issue. There will not be one solution to this problem, but many different issues that need to be addressed to prepare for these changes,’ said Smith. ‘I’m afraid if we don’t come to grips with this as a society, health care may be the next bubble to burst.’

In addition to Smith, other M. D. Anderson authors on the study include: Thomas Buchholz, M.D., professor and chair of the Department of Radiation Oncology and the study’s senior author; Gabriel Hortobagyi, M.D., professor and chair of the Department of Breast Medical Oncology; and Grace Smith, M.D., Ph.D., assistant professor in the Department of Radiation Oncology. Arti Hurria, M.D., post-doctoral fellow in the Department of Medical Oncology, City of Hope Cancer Center, also is a contributing author on the study.”

Sources:

Genetic Variations In miRNA Processing Pathway & Binding Sites Help Predict Ovarian Cancer Risk

“Genetic variations in the micro-RNA (miRNA) processing pathway genes and miRNA binding sites predict a woman’s risk for developing ovarian cancer and her prospects for survival, researchers from The University of Texas M. D. Anderson Cancer Center reported at the 100th annual meeting of the American Association for Cancer Research. … The unique study was the first to examine the association of genetic variants related to miRNA with ovarian cancer risk, overall survival for ovarian cancer patients, and platinum-based chemotherapy response. …”

Genetic variations in miRNA processing pathway and binding sites help predict ovarian cancer risk – Several variations indicate likelihood of response to platinum-based chemotherapy

DENVER – Genetic variations in the micro-RNA (miRNA) processing pathway genes and miRNA binding sites predict a woman’s risk for developing ovarian cancer and her prospects for survival, researchers from The University of Texas M. D. Anderson Cancer Center reported at the 100th annual meeting of the American Association for Cancer Research.

wu

Xifeng Wu, M.D., Ph.D., Professor, Department of Epidemiology, The University of Texas M.D. Anderson Cancer Center

‘We found a gene dosage effect, the more unfavorable variations a woman has, the greater her ovarian cancer risk and the shorter her survival time,’ said senior author Xifeng Wu, M.D., Ph.D., professor in M. D. Anderson’s Department of Epidemiology. Median survival, for example, ranged from 151 months for women with fewest unfavorable variations to 24 months for those with the most.

Several variations also indicate likely response to platinum-based chemotherapy.

‘Our findings have the potential clinical application of indicating a patient’s prognosis and showing who will respond to different therapies by analyzing a single blood sample,’ Wu said. ‘We also will incorporate this genetic information with epidemiological information to build a comprehensive model to predict susceptibility to ovarian cancer.’

The team chose the miRNA processing pathway because it is crucial to production of miRNAs, the small molecules that regulate between one third and half of all genes. The researchers also chose the binding sites on host genes where miRNAs exert their effects on gene expression.

They analyzed 219 potential functional single nucleotide polymorphisms (SNPs) – variations of a single DNA building block in a gene – in eight genes that process miRNA and at the miRNA binding sites of 129 cancer-relevant genes. The study examined genetic information from 417 cancer patients and 417 healthy controls. To minimize the possible confounding effects of ethnicity, 339 Caucasian cases and 349 controls were analyzed.

They discovered 12 SNPs to be significantly associated with ovarian cancer risk. Moreover, compared to women with five or fewer unfavorable genotypes, women with eight or more of these unfavorable genotypes were 4.5 times more likely to develop ovarian cancer and women with six to eight unfavorable SNPs were at twice the risk.

The team also found 21 SNPs significantly associated with overall survival. Median survival was 151 months for women with six or fewer unfavorable variations; 42 months for those with seven to nine unfavorable variations; and 24 months for those with 10 or more. One of the outcome risk SNPs also was strongly associated with platinum-based chemotherapy response, with those having the SNP 3.4 times less likely to respond to chemotherapy.

Wu collaborated with Dong Liang, Ph.D, in the College of Pharmacy and Health Sciences, Texas Southern University, and Karen Lu, M.D., professor in M. D. Anderson’s Department of Gynecologic Oncology, on this study.

The unique study was the first to examine the association of genetic variants related to miRNA with ovarian cancer risk, overall survival for ovarian cancer patients, and platinum-based chemotherapy response. Such a wide-ranging inquiry was made possible by M. D. Anderson’s extensive clinical and genetic data sets, Wu said.

Co-authors with Wu, first author Liang, Ph.D., and Lu are; Jie Lin, Ph.D., Xia Pu, Yuanqing Ye, Ph.D., all in the Department of Epidemiology; and Larissa Meyer, M.D., in the Department of Gynecologic Oncology at M. D. Anderson Cancer Center. Pu is a graduate student at The University of Texas Graduate School of Biomedical Sciences at Houston, which is a joint effort of M. D. Anderson and The University of Texas Health Science Center at Houston.

This research was supported by an award by the Department of Defense Ovarian Cancer Research Program.”

About M. D. Anderson

The University of Texas M. D. Anderson Cancer Center in Houston ranks as one of the world’s most respected centers focused on cancer patient care, research, education and prevention. M. D. Anderson is one of only 40 comprehensive cancer centers designated by the National Cancer Institute. For four of the past six years, including 2008, M. D. Anderson has ranked No. 1 in cancer care in “America’s Best Hospitals,” a survey published annually in U.S. News & World Report.

Sources:

Tumor-Promoting Protein COX-2 Is The Target Of First Joint Symposium Between AACR & ASCO

An inflammatory protein implicated in a variety of cancers is the target of the first joint symposium between the nation’s two premier cancer research organizations.  The presidents of the American Association for Cancer Research (AACR) and the American Society of Clinical Oncology (ASCO) organized the session focused on the COX-2 enzyme and cancer treatment Monday afternoon — April 20, 2:30-4:30 p.m., in rooms 205-207 of the Colorado Convention Center — at the AACR’s 100th Annual Meeting 2009 in Denver.  A similar symposium on new molecular targets will be conducted at ASCO’s annual meeting in May 29- June 2 in Orlando.  COX-2 is best known as a target for preventing dangerous polyps that lead to colorectal cancer, but it is also advancing as a target for treatment of many solid tumors. …

“Leading cancer organizations team up on tumor-promoting protein – AACR and ASCO begin joint symposia at annual meetings with focus on COX-2

An inflammatory protein implicated in a variety of cancers is the target of the first joint symposium between the nation’s two premier cancer research organizations.

duboismdander

Raymond DuBois, M.D., Ph.D., President, AACR; Provost and Executive Vice President, The University of Texas M. D. Anderson Cancer Center

The presidents of the American Association for Cancer Research (AACR) and the American Society of Clinical Oncology (ASCO) organized the session focused on the COX-2 enzyme and cancer treatment Monday afternoon — April 20, 2:30-4:30 p.m., in rooms 205-207 of the Colorado Convention Center — at the AACR’s 100th Annual Meeting 2009 in Denver. A similar symposium on new molecular targets will be conducted at ASCO’s annual meeting in May 29- June 2 in Orlando.

COX-2 is best known as a target for preventing dangerous polyps that lead to colorectal cancer, but it is also advancing as a target for treatment of many solid tumors.

‘Our symposium is timely because we are starting to see data from Phase II and Phase III clinical trials about COX-2 inhibition following post-surgical chemotherapy in colon cancer patients,’ said Raymond DuBois, M.D., Ph.D., president of AACR and provost and executive vice president at The University of Texas M. D. Anderson Cancer Center.

‘There’s been a great deal of preclinical and translational research addressing COX-2 overexpression in tumors and its role in cancer growth and survival. In prevention, inhibiting this enzyme reduces the number of high-risk precancerous polyps by 66 percent,’ DuBois said. ‘The time is ripe to combine basic science and clinical expertise to advance the therapeutic potential of this approach.’

Joint efforts are critical to the development of new approaches against cancer, said ASCO President Richard L. Schilsky, M.D., professor of medicine at the University of Chicago Medical Center.

‘The development of targeted therapies for cancer prevention and treatment requires the close collaboration and combined resources of basic scientists and clinical investigators,’ Schilsky said. ‘The success of targeted therapy for cancer depends first and foremost on a comprehensive understanding of the biology of the drug target coupled with a robust assay to assess target inhibition and a drug that hits the target. With these ingredients in place, clinical trials can be designed to assess the impact of treatment in the population most likely to benefit.’

schilsky

Richard L. Schilsky, M.D., President, ASCO; Associate Dean for Clinical Research, Professor of Medicine at the University of Chicago Medical Center.

‘The AACR/ASCO Symposium illustrates these core principles and demonstrates that continued progress against cancer requires the partnership of all investigators and practitioners represented by these two great organizations,’ Schilsky said.

The idea for joint symposia at each organization’s annual meeting has been discussed for years and was advanced by immediate past presidents William Hait, M.D., Ph.D., of AACR and Nancy Davidson, M.D., of ASCO.

DuBois and Schilsky co-chair the symposium. Scheduled presentations are:

  • COX-2 and Cancer Biology by DuBois, who discovered the enzyme’s overexpression in tumors.
  • Overview of COX-2 as a Target for Cancer Treatment, by Schilsky.

*          *          *

AACR is the world’s oldest and largest professional organization dedicated to advancing cancer research. ASCO is the world’s leading professional organization representing physicians who care for people with cancer. Many scientists and physicians are members of both organizations.”

Source: Leading Cancer Organizations Team Up on Tumor-Promoting Protein – AACR and ASCO begin joint symposia at annual meetings with focus on COX-2, M.D. Anderson News Release, The University of Texas M.D. Anderson Cancer Center, April 17, 2009.

Comment:  The relationship between ovarian cancer and COX-2 remains unclear.  Some in vitro and in vivo studies make a connection between ovarian cancer and COX-2, while others suggest that COX-1 is more relevant to current ovarian cancer research.  It is an area that warrants further investigation.

Recent Studies Re Ovarian Cancer and COX-2: