Pancreatic cancer is a devastating disease characterized by the progressive accumulation of genetic mutations resulting in an untreatable condition. Pancreatic cancer is the eighth leading cause of cancer death worldwide and it is the fourth leading cause of cancer deaths in USA. Nearly 30,000 deaths each year in the United States are due to pancreatic cancer. The prognosis for pancreatic cancer is extremely poor with less than 5% of diagnosed patients surviving for 5 years due to the aggressiveness of the disease and the lack of effective therapies. Even combination therapy, such as surgery with radiation and chemotherapy, has not significantly improved the survival rate for patients with pancreatic cancer. Therefore, novel therapeutic strategies are required to treat this aggressive malignancy. Dysregulation of signaling pathways, including glycogen synthase kinase-3 (GSK-3), may lead to uncontrolled cell growth and hence tumor development. Thus, manipulation of these various cellular signaling pathways may be a potential therapeutic target. In this proposal, we plan to investigate the isoform specific growth inhibition and the mechanism of growth suppression utilizing shRNA against GSK-3 isoforms and small molecule inhibitors. In our preliminary studies, pancreatic cancer cells treated with GSK-3 inhibitor showed growth suppression which is associated with a significant reduction in active Notch1 and Notch3 proteins. Given the importance of the various pathways impacted by Notch, it is possible that Notch may be positively regulated by GSK-3. Thus, we hypothesize that Notch1 and/or Notch3 is most likely a key downstream target of GSK-3 inhibition in pancreatic cancer cells. In order to validate the effects seen in in vitro studies on pancreatic cancer cell lines with small molecule inhibitors, we will develop a xenograft model of tumor progression using GSK-3 isoform knock-out human pancreatic cancer cell lines. Since the activations and regulations of GSK-3??and GSK-3? have not been well established, the results from this proposal will determine the functional role of GSK-3 isoforms in regulating Notch.

Public Health Relevance

Pancreatic cancer is the eighth leading cause of cancer death worldwide and it is the fourth leading cause of cancer deaths in USA. The prognosis for pancreatic cancer is extremely poor and nearly 30,000 deaths each year in the United States. Less than 5% of patients with pancreatic cancer survive for 5 years due to the aggressiveness of the disease and the lack of effective therapies. Even combination therapy such as surgery with radiation and chemotherapy has not significantly improved the survival rate for patients with pancreatic cancer. Therefore, novel therapeutic strategies are required to treat this aggressive malignancy.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Small Research Grants (R03)
Project #
1R03CA155691-01A1
Application #
8191435
Study Section
Tumor Cell Biology Study Section (TCB)
Program Officer
Yassin, Rihab R,
Project Start
2011-07-06
Project End
2013-06-30
Budget Start
2011-07-06
Budget End
2012-06-30
Support Year
1
Fiscal Year
2011
Total Cost
$74,250
Indirect Cost
Name
University of Wisconsin Madison
Department
Surgery
Type
Schools of Medicine
DUNS #
161202122
City
Madison
State
WI
Country
United States
Zip Code
53715
Kunnimalaiyaan, Selvi; Trevino, Jose; Tsai, Susan et al. (2015) Xanthohumol-Mediated Suppression of Notch1 Signaling Is Associated with Antitumor Activity in Human Pancreatic Cancer Cells. Mol Cancer Ther 14:1395-403
Kunnimalaiyaan, Selvi; Gamblin, T Clark; Kunnimalaiyaan, Muthusamy (2015) Glycogen synthase kinase-3 inhibitor AR-A014418 suppresses pancreatic cancer cell growth via inhibition of GSK-3-mediated Notch1 expression. HPB (Oxford) 17:770-6
Somnay, Yash; Chen, Herbert; Kunnimalaiyaan, Muthusamy (2013) Synergistic effect of pasireotide and teriflunomide in carcinoids in vitro. Neuroendocrinology 97:183-92
Somnay, Yash; Simon, Kevin; Harrison, April D et al. (2013) Neuroendocrine phenotype alteration and growth suppression through apoptosis by MK-2206, an allosteric inhibitor of AKT, in carcinoid cell lines in vitro. Anticancer Drugs 24:66-72
Somnay, Yash R; Kunnimalaiyaan, Muthusamy (2012) The Phosphatidylinositol 3-kinase/Akt Signaling Pathway in Neuroendocrine Tumors. Glob J Biochem 3: