Project 1: Metformin for the Chemoprevention of Endometrial Cancer in Obese, Insulin-Resistant Women
Karen H. Lu, M.D. (Principal Investigator – Clinical), Cheryl L. Walker, Ph.D. (Principal Investigator – Basic), and Rosemarie Schmandt, Ph.D. (Collaborator)
Obese women clearly are at increased risk for developing endometrial cancer. Numerous epidemiologic studies have demonstrated that obesity is strongly associated with an increased risk of endometrial cancer. While an average woman has a 3% lifetime risk of endometrial cancer, obese women have a 9-10% lifetime risk of endometrial cancer. In a review of diet and cancer by the American Institute for Cancer Research and World Cancer Research Fund (WCRF), authors stated that the evidence relating body mass index and cancer is strongest for endometrial cancer. While excessive production of extragonadal estrogens (estrone) in the adipose tissue of obese women is presumed to be the major contributor to the risk of endometrial cancer, increased serum estrogen levels alone are unlikely to fully account for this effect. Studies by our group and others suggest that insulin resistance associated with obesity contributes to the increased risk of endometrial cancer. In addition, data from our previous funding period suggest that other mechanisms are involved in activating pro-proliferative signaling pathways in the obese endometrium.
For the current studies, our central hypothesis is that metformin can decrease endometrial hyperproliferation and can act as a chemopreventive agent in insulin-resistant obese women. Our three specific aims are 1) to test the hypothesis that metformin can reverse the estrogen-dependent hyperproliferation in the endometrium in an animal model of obesity- induced insulin-resistance, 2) to study novel mechanisms related to the use of metformin for the prevention of endometrial cancer. More specifically, we will examine the hypothesis that adipokines expressed in adipose tissue regulate endometrial proliferation via adipokine receptors, and metformin treatment can prevent this proliferation, and 3) to assess the ability of metformin to modulate surrogate endometrial biomarkers in a cohort of obese, insulin resistant women. It is the goal of this Project to develop novel strategies for the chemoprevention of endometrial cancer in obese, insulin-resistant women, a high risk cohort.
The long term goal of this Project is to develop novel strategies for the chemoprevention of endometrial cancer in obese, insulin-resistant women, a high risk cohort. A clinical prevention trial will examine whether metformin, a widely used drug for insulin resistance and diabetes, can potentially prevent endometrial hyperplasia and cancer. Studies that seek to understand the fundamental changes in the endometrium of obese versus lean women will also be performed.
Project 2: Strategy for the Incorporation of Tissue Biomarkers in the Clinical Management of Endometrial Cancer Patients
Russell R. Broaddus, M.D., Ph.D. (Principal Investigator – Basic), Sean C. Dowdy, M.D. (Principal Investigator – Clinical), Thomas W. Burke, M.D. (Principal Investigator – Clinical), Paul Goodfellow, Ph.D. (Co-Investigator), David S. Loose, Ph.D. (Co-Investigator), Pamela T. Soliman, M.D. (Co-Investigator), and Michael Frumovitz, M.D. (Collaborator)
Crucial gaps in knowledge prevent the providing of ideal individualized care to women with endometrial cancer. The extent of lymphadenectomy and the identification of which patients would benefit the most from complete surgical staging are unresolved clinical issues.
A second important gap is the ability to predict which women with low stage endometrioid-type endometrial cancer will suffer recurrence. We have used genomic approaches to identify tissue biomarkers of endometrial cancer. These biomarkers have been validated in a large set of endometrial cancers at MDACC, and we have documented their close association with stage and recurrence. Next, we will validate these findings in independent data sets. We hypothesize that quantifying genes associated with EMT and estrogen’s growth regulatory actions in the endometrium as a “biomarker score” will provide a clinically useful tool to assist in the decision to perform complete surgical staging on women diagnosed with endometrial cancer and will predict which women with stage I and stage II endometrioid carcinomas will recur.
In Aim 1, we will validate the association of our biomarkers with endometrial cancer stage in an independent data set obtained from a series of patients who underwent comprehensive surgical staging at the Mayo clinic. We will also establish that the biomarker score computed from formalin-fixed, paraffin-embedded endometrial biopsies is a good approximation of the same scores based on tissue from the final hysterectomy. We will determine the association of the biomarker panel with endometrioid carcinoma recurrence in independent data sets obtained from Mayo Clinic and Washington University.
In Aim 2, reverse phase protein lysate array (RPPA) will be used to identify proteins and phospho-proteins that are associated with endometrioid carcinoma stage. These newly identified biomarkers will be used to augment our currently existing panel. We will also develop methodology to perform RPPA using formalin-fixed tissues so that this technology becomes more relevant to clinical samples. Finally, RPPA will be used to help identify proteins that interact with EIG121, one of the more exciting but least understood biomarkers in our existing panel.
Currently, we cannot reliably identify pre-operatively the endometrial cancer patients who would benefit most from extensive surgical staging. In addition, we cannot reliably predict the women with low stage endometrioid-type endometrial cancer who will suffer recurrence. We propose here to validate and augment a biomarker panel that can help to better individualize endometrial cancer patient care.
Project 3: EphA2 Targeting in Uterine Carcinoma
Anil K. Sood, M.D. (Principal Investigator – Basic), Robert L. Coleman, M.D. (Principal Investigator – Clinical), and Russell R. Broaddus, M.D., Ph.D. (Collaborator)
Despite refinements in surgery, radiation and chemotherapy, the mortality rates of women with advanced uterine carcinoma have remained largely unchanged for decades. Recognition of this “therapeutic plateau” has focused intense investigation into strategies targeting mechanisms of tumor growth and progression. Our preliminary studies have identified a novel therapeutic target, EphA2, which is overexpressed in a substantial proportion of uterine cancers, is associated with poor overall survival, and mechanistically regulates angiogenesis. While present in tumor and tumor-associated vasculature, it is low or absent in most normal tissues, making its differential presence and function an attractive therapeutic target. The overall goal of this proposal is to develop EphA2 targeted therapeutic strategies for uterine carcinoma and to characterize its biological functions in regulating uterine cancer growth and progression. We will first leverage the differential expression of EphA2 in tissue as a targeting beacon to deliver a novel molecular immunoconjugate, monomethylauristatin F (MMAF; MEDI-547). This dolastatin-analogue is attached to a monoclonal antibody, which selectively binds EphA2. Our preliminary data demonstrate that MEDI-547 inhibits tumor growth and metastasis in orthotopic animal models of uterine cancer. However, it is not known whether EphA2 expression on the tumor cells is required for MEDI-547 to be efficacious. This question will be addressed experimentally in Aim 1. The findings from Aim 1 will guide a Phase Ib clinical trial in Aim 2 that will examine the safety, toxicity, and efficacy of the MEDI-547 in patients with recurrent uterine carcinoma. In addition to targeting EphA2 for delivery of a cytotoxic agent, our preliminary data suggest that EphA2 silencing can directly affect tumor and endothelial cell functions. These effects may be mediated via reduced activation of downstream non-receptor kinases such as focal adhesion kinase (FAK). However, the mechanisms by which EphA2 regulates tumor growth are not fully understood and will be further examined in Aim 3. In this Aim, we will also examine the therapeutic efficacy of EphA2 gene silencing. To achieve efficient systemic in vivo delivery of short interfering RNA (siRNA) for gene silencing, we have developed and characterized biocompatible nanoparticle-based delivery methods that will be utilized for the experiments proposed in Aim 3.
There are not many options for treating advanced/recurrent endometrial cancer. Targeted therapy using monoclonal antibodies against tumor-specific antigens is a highly attractive therapeutic approach. EphA2 as a target for such therapy has theoretical advantages since it is overexpressed in a substantial proportion of tumors and is largely absent in most normal adult tissues. Moreover, EphA2 has been implicated in a number of processes related to cancer invasion, angiogenesis, and metastasis.
Project 4: Targeting the PI3K Signaling Pathway in Endometrial Carcinoma
Gordon B. Mills, M.D., Ph.D. (Principal Investigator – Basic) and Shannon N. Westin, M.D. (Principal Investigator – Clinical)
We and others have demonstrated that the phosphatidylinositol-3-kinase (PI3K)/PTEN/AKT/mTOR pathway is activated in over 60% of endometrial cancers by mutations in the PTEN (30-50%), PIK3CA (20-40%), PIK3R1 (20%) and AKT1 (~2%) genes. Further, we and others have shown that the RAS/RAF pathway is activated by KRAS mutations in ~20% of endometrial cancers. In contrast to other cancer types, none of these mutations are mutually exclusive and two or more thus frequently occur in the same endometrial tumor. We and others have also recently demonstrated that KRAS mutations predict a lack of response to PI3K pathway-targeted therapies in cancer cells and vice versa. Thus, in this application, we will test the hypotheses in vitro and in vivo in endometrial cancer that: 1. PI3K pathway-targeted drugs will be selectively active in tumors with mutations in the PI3K pathway in the absence of KRAS mutations, 2. Specific aberrations in the PI3K pathway will determine the response to targeting different nodes in the PI3K pathway, 3. Aberrations in the RAS/RAF pathway in the absence of PI3K pathway mutations will render tumors responsive to RAS/RAF-pathway targeted drugs (e.g. MEK inhibitors), and 4. Cells with coordinate mutations in both the PI3K and RAS/RAF pathways will be resistant to PI3K pathway inhibitors and MEK inhibitors alone but sensitive to concurrent targeting of both pathways.
Our specific aims are:
Aim 1: To determine effects of mutations in the PI3K and RAS/RAF pathways on downstream signaling events and clinical correlates in endometrial cancer.
Aim 2: To determine whether specific aberrations in the PI3K and RAS/RAF pathways predict effects of targeting specific nodes in the PI3K and RAS/RAF pathways.
Aim 3: To identify and validate predictive and pharmacodynamic markers of antitumor efficacy for PI3K- and RAS/RAF-targeted therapies in endometrial cancer.
Aim 4: To determine whether predictive and pharmacodynamic markers indicate responsiveness to the dual PI3K/mTOR inhibitor GSK2126458A in a phase II clinical trial in advanced endometrial cancer.
PI3K and RAS/RAF pathway mutations occur in ≥65% of endometrial cancers. It is therefore likely that our studies of these two pathways as therapy targets in endometrial cancer will benefit a significant proportion of women with endometrial cancer when translated to the clinic. In addition, these mutations are seen frequently in a broad spectrum of tumor types including breast and colorectal cancers. Thus, the proposed studies of PI3K and RAS/RAF pathway inhibition in endometrial cancer will likely also have broad applicability to other tumor types.
Core A: Administrative Core
Karen H. Lu, M.D. (Director), Russell R. Broaddus, M.D., Ph.D. (Director), Thomas W. Burke, M.D. (Co-Director), George M. Stancel, Ph.D. (Co-Director), and Heetae Kim (Program Manager)
To ensure the success of the Uterine SPORE program at M. D. Anderson, the overall goal of the Administrative Core is to provide effective management and administration of all activities relating to each project, core, and developmental program in the SPORE. The Administrative Core will actively work to communicate and disseminate information within our internal SPORE investigators as well as facilitate information sharing and collaborations with other SPOREs and external constituencies. The Core will provide a structure to assure integration of diverse scientific disciplines into a unified multidisciplinary approach for achieving excellence in translational endometrial cancer research. Importantly, the Administrative Core will monitor timelines and ensure both basic science and clinical trial aims are met for all SPORE projects. The Core will provide administrative support to the individual SPORE projects, cores, and developmental programs, as well as to the Internal and External Advisory Committees and the Patient Advocates. The Core will assist in preparation of all reports, abstracts, and manuscripts resulting from SPORE activities. The Administrative Core will assure compliance with regulations at all levels and maintain communication among investigators, as well as with other translational researchers, gynecologic cancer SPOREs, the Gynecologic Oncology Group and SPOREs from other disease sites. The Core will convene all meetings, including the Executive Committee, Internal Advisory Committee, External Advisory Committee, and other educational and regulatory activities. The Administrative Core will provide support for data management and for the integration of a centralized data repository accessible by all SPORE investigators. Dr. Karen Lu, Director of the Administrative Core and Director for the overall SPORE, will direct these activities with the assistance of the Co-Director, Dr. Russell Broadus, as well as the Co-Principal Investigators for the overall SPORE.
Core B: Pathology Core
Russell R. Broaddus, M.D., Ph.D. (Director), Karen H. Lu, M.D. (Co-Director), and Anais Malpica, M.D. (Collaborator)
The goal of the Pathology Core is to provide frozen tissue, paraffin-embedded tissue, and histopathological expertise related to the specific needs for the research projects comprising this SPORE proposal. To meet this goal, the following Specific Aims are proposed for this Core. Aim 1 is to maintain a frozen and paraffin-embedded tissue repository of endometrial cancers, hyperplasias, and normal endometrial samples. Aim 2 is to provide pathological review for all clinical specimens utilized in the SPORE projects and for related clinical trials and to provide histopathological technical services as necessary. Aim 3 is to establish a blood/urine/ascites fluid collection from patients undergoing hysterectomy for endometrial cancer and endometrial hyperplasia and from patients undergoing hysterectomy for non-endometrial pathology (uterine leiomyomas, cervix dysplasia, endometriosis). Such fluids will provide resources for the future testing of putative diagnostic/prognostic markers for endometrial cancer. Aim 4 is to create and maintain a database for all frozen and paraffin-embedded endometrial tissues and fluids collected by the Core.
Core C: Biomarker Core
David S. Loose, Ph.D. (Director)
The biomarker core will provide a centralized resource for the rapid, high throughput quantification of transcripts and proteins. Transcripts will be quantified using quantitative PCR (Q-PCR). In addition the Biomarker Core will provide for genome-wide microarray analysis using an Illumina Beadstation. Quantification of protein levels in blood or tissue lysates will be done using a MesoScale Sector Imager or by reverse-phase protein array (RPPA) The biomarker core will serve to provide: 1) quantitative mRNA levels for known genes that are involved in proliferation and implicated in cancer progression; 2) identification of unique proteins, genes and expression profiles in cells or tissues after a molecular or pharmacologic manipulation; 3) validation of the expression of genes that are initially identified in screening by microarrays, 4) quantification of protein levels both as an independent validation technique and to determine the relationship between transcript levels and protein levels. Specific Aims 1-4 represent interactions between projects in the SPORE and the Biomarker Core. Specific Aim 1 Metformin for the chemoprevention of endometrial cancer in obese, insulin resistant women. These studies will use both animal models of obesity and conduct a clinical trial using metformin and examine the impact on endometrial cancer. Biomarkers that will be measured include Ki-67, Cyclin A, sFRP1, sFRP4, survivin, EIG121, RALDH2, PR, ER, IGF-1 IGF-1R. RPPA and microarrays will also be used in these studies. Specific Aim 2. Strategy for the Incorporation of Tissue Biomarkers in the Clinical Management of Endometrial Cancer Patients. This project will assess the utility of a panel of 7 previously identified biomarkers in a large number of FFPE endometrial samples. This project will also use RPPA to help discover new biomarkers to augment the current biomarker panel. Specific Aim 3 EphA2 Targeting in Uterine Carcinoma. These studies will evaluate the function of EphA2 in cancer and conduct a clinical trial of a novel immuno-conjugate that targets the EphA2 receptor. Q-PCR will assess the biomarkers listed above, markers of angiogenesis, and cell free nucleic acids. Pre-and post- biopsy endometrial will be assayed for the core biomarkers, markers of angiogenesis and EphA2 transcripts. Microarray studies will be conducted to identify both pathways and novel genes regulated by EphA2. Specific Aim 4 Targeting the PI3K Signaling Pathway in Endometrial Carcinoma. In these studies the Core will examine by RPPA approximately 550 tissue specimens for alteration in the expression and phosphorylation of members of the PI3K signaling pathway. Specific Aim 5 is a project within the Biomarker Core that will perform microarray analysis and QPCR validation on approximately 90 samples from patients with HNPCC at baseline and following 3 months of chemoprevention therapy with either oral contraceptives or depot medroxyprogesterone
Core D: Biostatistics and Bioinformatics Core
Ying Yuan, Ph.D. (Director), Charlotte Sun, Dr.P.H. (Co-Investigator), Mark Munsell, M.S. (Statistical Analyst), Diana Urbauer, M.S. (Statistical Analyst), and Caimiao Wei, Ph.D. (Bioinformatics Analyst)
The Biostatistics and Bioinformatics Core serves multiple needs for the planning and conduct of the SPORE's basic and translational research. The Core provides hypothesis refinement, experimental design, analysis, data management, and informative presentation of results across all projects of the SPORE. From a biostatistical perspective, design and analysis of laboratory and clinical projects are performed at the direction of Dr. Ying Yuan. Dr. Caimiao Wei contributes her expertise to the analysis of microarray and genome data in this SPORE. Data from SPORE clinical trials, animal studies, and laboratory experiments are analyzed with the support of Dr. Charlotte Sun, Mr. Mark Munsell, and Ms. Diana Urbauer. Dr. Ying Yuan will also oversee data base management and data integration. Data integration will build on a new deployment of the existing data service S3DB. This SPORE resource is used to augment existing M.D. Anderson biostatistics and bioinformatics resources and to align these considerable resources with SPORE research objectives.
The Specific Aims of the Biostatistics and Bioinformatics Core are:
Specific Aim 1: To provide guidance in the design and conduct of clinical trials and other experiments arising from the ongoing research of the SPORE.
Specific Aim 2: To provide the innovative statistical modeling, simulation techniques, and data analyses needed by the Projects, Developmental Projects, and other Cores to achieve their Specific Aims.
Specific Aim 3: To ensure that the results of all Projects are based on well-designed experiments and are appropriately interpreted.
Specific Aim 4: Provide a web-based environment where data bases can be created and shared within the multi-institutional Uterine SPORE scientific community.