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University of Texas M.D. Anderson Cancer Center
Project 1 We have recently demonstrated that p202, an interferon-inducible protein, associates with multiple anti-tumor activities in a pancreatic orthotopic animal model and its expression is associated with multiple anti-tumor activities that induce inhibition of tumor growth, reduced tumorigenecity, prolonged survival, and remarkably, suppression of metastasis and angiogenesis. In vitro invasion assay also showed that p202-expressing pancreatic cancer cells are less invasive than those without p202 expression. It suggests that p202 gene may be used to suppress development of pancreatic cancer in a gene therapy setting. To this end, we have also recently developed a stabilized nonviral gene delivery system, SN that can deliver a therapeutic gene through i. v. injection to effectively suppress the development of both mammary tumors and prostate cancer in orthotopic animal models. In an attempt to develop a gene therapy approach for pancreatic cancer, we have initiated a pilot experiment to demonstrate treatment efficacy by using p202/SN liposome complex in a nude mice xenograft model, suggesting the feasibility of using p202/SN liposome in future preclinical gene therapy experiments. The long-term goal of this project is to develop an effective therapeutic approach to treat pancreatic cancer. Specifically, we would like to establish effective therapeutic approaches using gene therapy via liposome/adenoviral delivery systems in orthotopic animal models. To achieve this goal, three specific aims are proposed:
Success of this project will ensure to initiate a phase I clinical trial within the funding period of the Spore application. Mien-Chie Hung, Ph.D. Project 2 Cyclooxygenase-2 (COX-2) is the rate-limiting enzyme in the synthesis of E-series prostaglandins and other arachidonic acid-derived lipid regulators. It is a critical factor in acute and chronic inflammatory diseases, and excellent chemical inhibitors of Cox-2 are currently being used in the treatment of these diseases. Cox-2 is overexpressed in a large fraction of human pancreatic tumors, but the mechanisms underlying its expression and its effects on tumor biology have not been determined. Our preliminary data indicate that serum factor(s) promote the expression of both Cox-2 and an upstream component of the same pathway (phospholipase A 2 ) via an NFkB-dependent mechanism. Furthermore, although selective and non-selective COX-2 inhibitors do not significantly affect the growth of pancreatic cancer cells on their own, they synergistically increase the levels of apoptosis observed in cancer cells treated with inhibitors plus arachidonic acid. Finally, preliminary studies in tumor xenografts employing three-color immunofluorescence/laser scanning cytometry (LSC) analyses indicate that tumor-associated endothelial cells express very high levels of COX-2 in vivo, and a selective COX-2 inhibitor not only stimulates tumor cell apoptosis but also dramatically increases levels of apoptosis in tumor-associated endothelial cells. We will identify the molecular defects and extracellular signal(s) that work in concert to promote COX-2 expression in pancreatic cancer cell lines, focusing on serum- and lipid-derived factors and the genetic alterations previously implicated in pancreatic cancer progression. We will also define the molecular mechanisms underlying COX-2-mediated inhibition of arachidonic acid-induced apoptosis. Finally, we will determine the mechanisms underlying COX-2-mediated endothelial cell survival using a combination of in vitro and xenograft/in vivo approaches. An important component of this effort will be to measure the effects of COX-2 inhibition in biopsies obtained from patients on a Phase II clinical trial. This project will provide important new information about cellular survival mechanisms in human pancreatic cancer with immediate relevance to the therapy. David McConkey, Ph.D. Project 3 Background: Pancreatic adenocarcinoma is the 4 th leading cause of adult cancer mortality in the United States. At the time of diagnosis, most pancreatic cancer patients present with advanced disease. A key point that has recently emerged from analysis of the genetic alterations of pancreatic cancer is that this malignancy exhibits a unique profile of mutations that distinguishes it from all others . However, the interplay of the genetic alterations and specific signaling cascades that mediate the metastatic and chemotherapy-resistant phenotypes of pancreatic cancer is poorly understood. Consequently, effective therapeutic strategies for pancreatic cancer remain to be developed. Preliminary Data: Overexpression of the epidermal growth factor receptor (EGFR) , which occurs in approximately 90% of human pancreatic cancers, may be one of the few genetic alterations that significantly correlate with survival. Our recent data demonstrated that activation of the EGFR leads to activation of Akt and NF- k B, suggesting that EGFR may be an important therapeutic target. We previously reported the first evidence that NF- k B is constitutively activated in 70% (14 of 20) of human pancreatic adenocarcinomas and 9 of 11 human pancreatic cancer cell lines. However, NF- k B is not activated in normal pancreatic tissues or in immortalized but nontumorigenic pancreatic epithelial cells. Our results show that inhibition of constitutive NF- k B activity by a phosphorylation defective I k B a (S32, 36A) suppresses tumorigenesis and liver metastasis of pancreatic cancer cells in an orthotopic nude mouse model, suggesting that the constitutive NF- k B activity plays a key role in pancreatic cancer. Furthermore, we and others have shown that activation of NF- k B, in turn, leads to expression of several NF- k B downstream target genes, such as uPA, VEGF, IL-8 and bcl-xl, that may mediate its cardinal clinical features of locally aggressive growth, metastasis, and chemotherapy resistance. Our results also show that activation of NF- k B encountered in most patients with pancreatic cancer may be due to the activation of EGFR and AKT signaling pathways. Thus, the EGFR, AKT, and NF- k B signaling pathways may provide novel targets for therapy to inhibit the metastatic and chemotherapy resistant phenotypes of pancreatic cancer. Rationale: Our preliminary data suggest that diverse agents, ranging from chemical inhibitors of Akt and NF- k B to more specific inhibitors, antibody to EGFR, EGFR-related protein (ERRP), and a dominant negative I k B a , can inhibit the growth and metastasis of pancreatic cancer in preclinical models. However, it remains unknown whether the approaches that directly target NF- k B, those that target NF- k B upstream activators, or combinations of these approaches with standard chemotherapy agents, such as gemcitabine, will be most effective. Thus, in this project we propose to study a series of signaling inhibitors to test the hypothesis that inhibition of NF- k B signaling pathways by these agents alone or in combination with gemcitabine will lead to greater therapeutic effects. The specific aims of this proposal are as follows: Specific Aim 1. To determine whether the effects of inhibiting NF- k B activity with IMC-C225, PS-341, PS-1145 (an IKK inhibitor) and a dominant negative I k B a delivered by liposome will enhance gemcitabine-induced apoptosis in pancreatic cancer cell lines grown in culture and implanted in the pancreas of nude mice. Specific Aim 2. To examine whether ERRP-mediated inhibition of EGFR and genistein-mediated Akt signaling cascades will sensitize various pancreatic cancer cell lines to gemcitabine-induced apoptosis. Specific Aim 3. To study whether the EGFR antagonist IMC-C225 (Cetuximab) given alone or in combination with gemcitabine will induce biologic and therapeutic responses in patients with metastatic pancreatic cancer in treated in a clinical trial. Significance: Our studies will (1) provide a better understanding of the role of cellular signaling inhibitors and their ability to block these pathways to sensitize pancreatic cancer cells to apoptosis, (2) reveal insights into the their mechanisms of action, (3) suggest appropriate combinations for clinical testing, and (4) establish the use of these agents in clinical trials. The information obtained from our studies will directly impact the management of patients with pancreatic cancer and provide a direction for the future studies required to extend the survival of these patients. Paul J. Chiao, Ph.D. Project 4 Human pancreatic cancers overexpress several major angiogenic molecules including basic fibroblast growth factor, epidermal growth factor receptor, endothelial nitric oxide synthase, insulin-like growth factor receptor, and vascular endothelial growth factor, and this overexpression is concomitant with elevated transcription factor Sp1 expression and activation. Because these molecules are potentially transactivated by Sp1 , disregulated expression and activation of Sp1 may be responsible for aberrant expression of multiple angiogenic molecules, leading, in turn, to the onset of the angiogenic phenotype and sustained tumor growth and metastasis. Therefore, Sp1 may be a critical marker for pancreatic cancer diagnosis and prognosis as well as a novel therapeutic target. This projecet will test this hypothesis by: 1) defining the prognostic value of Sp1 activation in human pancreatic cancer development and progression. Blood vessel density, expression of angiogenic molecules, and Sp1 expression and activity will be evaluated by examining tissues from normal pancreas and from different PanIN stages of pancreatic adenocarcinoma and pancreatic adenocarcinoma metastases. The relationship between the Sp1 activity, angiogenic phenotype, and various clinicopathologic characteristics of pancreatic cancer will be analyzed. The angiogenic phenotype is predicted to correlates with elevated Sp1 activity and with overexpression of angiogenic molecules, both of which have direct impacts on cancer development and progression. 2) providing evidence of a causal relationship between Sp1 overexpression and the angiogenic phenotype . The angiogenic, tumorigenic, and metastatic potential of various human pancreatic cancer cell lines differing in Sp1 expression will be systematically compared and Sp1 expression in highly and poorly angiogenic human pancreatic epithelial cell lines will be genetically modified to determine the effects of altered Sp1 activity on the expression of angiogenic molecules, angiogenesis, growth, and metastasis of pancreatic cancer in well-established orthotopic animal models. The level of Sp1 activity is expected to correlate directly with the tumorigenic and metastatic potential of human pancreatic cancer, and the alteration of Sp1 activity is expected to directly change the angiogenic phenotype of tumor cells in vitro and in vivo . 3) exploring the therapeutic effect of targeting Sp1 . This exploration will involve two distinct approaches, including a newly generated adenoviral delivery system of the dominant negative Sp1 gene and small molecule inhibitors of Sp1 binding activity. The Sp1 activity, expression of angiogenic molecules, and tumor vessel formation, growth, and metastasis will then be determined with preclinical models. Decreased Sp1 activity is anticipated to inhibit multiple angiogenic molecule expression, decrease angiogenesis, hence suppression of tumor growth and metastasis.Therefore, completion of these studies using molecular and cell biology techniques, animal models, and human specimens will provide insightful information for the development of potential diagnostic and therapeutic strategies for pancreatic cancer. Keping Xie, M.D., Ph. D. Project 5 Pancreatic cancer is the fourth leading cause of cancer deaths in the United States. Although risk factors for this cancer have not been well characterized, cigarette smoking is implicated in approximately one quarter to one third of pancreatic cancers, and long-term smoking, (more than 20 years), doubles the risk. We hypothesize that DNA repair capacity influences risk for pancreatic cancer, and that polymorphisms in DNA repair and cell cycle genes modulate the efficiency of DNA repair capacity, and therefore influence an individual's risk of developing pancreatic cancer. In order to address these questions, we will conduct a case-control study of 400 pancreatic cancer cases and 400 cousin controls who will be identified by their respective relatives. We will determine if selected polymorphisms in nucleotide excision repair (NER) genes and cell cycle genes, either alone, or in combination with smoking status, influence risk for pancreatic cancer. The polymorphisms are ERCC1, XPC, XPD / ERCC2, XPA, XPG/ERCC5, XPB/ERCC3 and XPF/ERCC4 for the NER pathway, and cyclin D1, p16, p21 and p53 for the cell cycle genes. The NER pathway is involved in repair of DNA damage caused by smoking, while cell cycle control genes are important in cellular response to DNA damage caused by smoking. We will assess the DNA repair capacity phenotype using the host cell reactivation assay and the tobacco carcinogen, benzo[a]pyrene (BPDE) as the mutagen, on cases and cousin controls. A complementary assay, BPDE-induced DNA adduct assay will also be carried out on the cases and cousin controls. We will determine if polymorphisms in cell cycle genes or genes in the NER pathway modulate the DNA repair capacity phenotype or the BPDE-induced DNA adducts phenotype. This will be achieved by correlating these phenotypes with the genotypes in cases and controls separately. A second goal (in cases only) will be to evaluate genetic predictors of response to therapy. For this case series approach, we will enroll 250 cases from the total group of 400 patients whom we estimate will have received pre-operative treatment with gemcitabine and radiation. We will determine if DNA repair capacity, BPDE-induced DNA adduct levels, polymorphisms in DNA repair genes, and/or polymorphisms in cell cycle genes modulate response to this treatment. The proposed studies were designed to elucidate genetic factors that may modulate risk for development of sporadic pancreatic cancer as well as response to chemoradiotherapy, and will provide important information that may lead to new strategies for the prevention, early detection and treatment of the disease. The proposed studies may also help to determine which subset of patients is more likely to respond to combined preoperative treatment with gemcitabine and radiation. Marsha L. Frazier, Ph.D. Core A The Administrative Core is critical to the success of the Pancreatic Cancer SPORE. The specific objectives of the Administrative Core are to:
The Administrative Core will be led by Drs. James L. Abbruzzese, Mien-Chie Hung and Douglas B. Evans, all of whom has extensive expertise in the successful and productive management of large, multidisciplinary research programs. The Core leaders maintain good working relationships with members of the National Cancer Institute and National Institutes of Health and are very familiar and in full compliance with all policies and procedures required of NCI- and NIH-funded research programs. James L. Abbruzzese, M.D., F.A.C.P. CORE B The Biostatistics and Information Management Core for the University of Texas M.D. Anderson Cancer Center Pancreas SPORE will be a comprehensive resource for data acquisition and management, designing clinical and basic science experiments, statistical analysis, and publishing translational research generated through the SPORE program. The Biostatistics and Information Management Core will incorporate sound experimental design principles within each project that will increase the clarity and enhance interpretability of study results. Each project will be provided with tailored analyses, accompanied by novel statistical development as necessary, to reveal apparent and hidden relationships among data. The Biostatistics and Data Management Core will provide expertise in the design of an integrated data management system to facilitate communication among all projects and cores. This process includes prospective data collection, data quality control, data security, and assurance of patient confidentiality. The Biostatistics and Data Management Core will collaborate with all project investigators to facilitate the timely publication of all data collected under the SPORE research program. The main objectives of the Biostatistics and Data Management Core are:
Core C Effective tissue procurement and utilization is vital for meaningful translational research activities. The Tissue Procurement and Distribution Core will work with each SPORE project and the Biostatistics and Information Management Core to ensure efficient and highly-coordinated procurement, use and storage of human tissue samples. The Core will obtain and maintain a repository of tissue samples (including tumor tissue, premalignant tissue (in the case of mucinous neoplasms including intraductal papillary mucinous neoplasms), adjacent non-malignant tissue, peripheral blood lymphocytes, and plasma) for laboratory use, with an effective coding system for all laboratory specimens to ensure patient confidentiality and prevent experimental bias. Standardized operating procedures will provide for optimal tissue collection and accurate processing, analysis and storage of each sample. Thus, the functions of the Tissue Procurement and Distribution Core are to facilitate acquisition, preservation, analysis and dispersal of clinical samples and to provide histopathologic characterization of tumor tissues for all project investigators. The Tissue Procurement, and Distribution Core has the following objectives:
Douglas B. Evans, M.D. M.D. Anderson Cancer Center James Abbruzzese, M.D., F.A.C.P. Douglas B. Evans M.D., F.A.C.S. Mien-Chie Hung, Ph.D. Kenneth R. Hess, Ph.D. Asif Rashid, M.D. N. Volkan Adsay, M.D. David McConkey Ph.D. Henry Q. Xiong, M.D., Ph.D. Paul J. Chiao, Ph.D. Fazlul H. Sarkar, Ph.D. Razelle Kurzrock, M.D., F.A.C.P. Keping Xie, M.D., Ph.D. Linus Ho, M.D., Ph.D. Marsha L. Frazier, Ph.D. Donghui Li, Ph.D. |
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