Pancreatic ductal adenocarcinoma (PDAC) has the highest mortality rate of all cancers, is rapidly becoming the second leading cause of cancer deaths in the U.S., and is estimated to cost the health care system $2.4 billion each year. Patients with PDAC have a 5-year survival rate of 7% and that number drops to 2% for individuals with metastatic disease. Unfortunately, there has been little progress in shifting patient outcome over the past 40 years, highlighting the need for innovative approaches to define the molecular pathways that influence PDAC development. PDAC can be initiated in exocrine epithelial cells that acquire an activating mutation in the KRAS protooncogene, causing the cells to transition to pancreatic intraepithelial neoplasia (PanIN) lesions that can progress into PDAC. A key transcriptional response to KRAS activity is increased expression of the physiological activator of the coagulation system, Tissue Factor (TF). TF mediates conversion of prothrombin to the active protease thrombin that in turn promotes extensive fibrin deposits within the tumor microenvironment (TME) and activates G-protein coupled protease-activated receptors (PARs) on target cells, including PDAC tumor cells, tumor-associated macrophages (TAMs) and cancer-associated fibroblasts (CAFs). The scientific premise is based on a known relationship between pancreatic cancer and high-level blood coagulation system activity, but is unique in that it will define newly discovered mechanisms of crosstalk by which specific coagulation factors in the TME promote PDAC pathogenesis. Our central hypothesis is that thrombin drives early PanIN development as well as advanced PDAC tumor growth and metastasis by mechanisms linked to both fibrin matrix deposition in the TME and PAR-1 signaling on tumor and TME cells promoting a feed forward pathway of PDAC disease. This hypothesis will be tested by utilizing a combination of unique genetically engineered mouse models, cutting-edge pharmaceutical reagents, and patient-derived PDAC tumor cells to pursue three Specific Aims - (1) determine how the thrombin-fibrin axis contributes to early PanIN development and late stage PDAC tumor growth and metastasis; (2) determine the individual mechanisms by which thrombin receptor PAR-1 signaling on tumor cells, TAMs and CAFs exacerbates distinct aspects of PDAC pathogenesis; and (3) determine the efficacy of pharmacological fibrin and PAR-1 inhibition in halting the progression of established mouse PDAC and human patient-derived xenograft tumors. These studies are significant because they will (i) be the first to define the impact of thrombin throughout PDAC disease; (ii) identify specific mechanisms of thrombin-dependent PDAC disease progression; and (iii) provide novel opportunities to target PDAC tumors using specific state-of-the-art inhibitors of fibrin matrix and PAR-1 signaling pathways. The discoveries made will greatly advance the understanding of mechanisms underlying PDAC disease and are expected to highlight novel therapeutic opportunities for developing improved treatment options - a long-term goal with the greatest benefit to patient outcome.

Public Health Relevance

Pancreatic ductal adenocarcinoma (PDAC) is expected to become the second leading cause of cancer deaths in the U.S. within the next 4 years, costing the health care system $2.4 billion each year. The primary goal of the proposed research is to define the mechanisms by which blood coagulation factors influence both the tumor microenvironment and primary and metastatic tumor cells in promoting PDAC disease. This research program is highly relevant to public health because it will foster creative discoveries in exploiting the coagulation system, leading to greatly improved therapies for PDAC patients

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
7R01CA211098-03
Application #
9946911
Study Section
Tumor Microenvironment Study Section (TME)
Program Officer
Ault, Grace S
Project Start
2017-06-19
Project End
2022-05-31
Budget Start
2019-06-01
Budget End
2020-05-31
Support Year
3
Fiscal Year
2019
Total Cost
Indirect Cost
Name
University of North Carolina Chapel Hill
Department
Pathology
Type
Schools of Medicine
DUNS #
608195277
City
Chapel Hill
State
NC
Country
United States
Zip Code
27599
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