In the model for the development of pancreatic cancer, the pancreatic ducts undergo a progressive series of architectural, cytologic, and genetic changes that are defined by degrees of pancreatic intraepithelial neoplasia (PanIN). The evaluation of PanIN has been challenging due to limited in vitro and in vivo models. The recent development of a mouse PanIN model through targeted endogenous expression of a K-ras mutant allele, the earliest recognized human genetic aberrancy, recapitulates human PanIN and provides a necessary tool to study its mechanisms. Recently, our laboratory was the first to identify a potential role for chemokine receptor CXCR4 in the growth and proliferation of PanIN. Using mouse and human PanIN tissues, we observed absence of CXCR4 expression in histologically normal pancreatic ducts, but increased CXCR4 expression in PanIN lesions. We also noted that activation of the CXCR4 receptor, by its specific ligand CXCL12, resulted in enhanced PanIN cell proliferation (Gut, 2008). Dysregulated K-Ras signaling transforms pancreatic ducts into PanIN lesions, but it also appears that these K-Ras dependent changes may be further driven by activated CXCR4. The establishment and use of a mouse PanIN model is a necessary and uniquely available preclinical tool for the investigation of human PanIN. It will allow us to explore and modify CXCR4 signaling pathways and its mediators. We hypothesize that CXCR4 signaling is requisite for PanIN proliferation and progression. Since discrete CXCR4 signaling leading to enhanced PanIN and pancreatic cancer proliferation has not been defined, our objectives are to define CXCR4 signal transduction in this regard and to assess in vivo therapeutic targeting of specific CXCR4 signaling mediators to prevent the initial development of PanIN or prevent its progression to invasive and metastatic pancreatic cancer. We propose the following Aims: 1) Aim I: Characterize CXCR4 signaling associated with enhanced proliferation and identify optimal targets to antagonize CXCR4-enhanced proliferation. 2) Aim II: Determine whether downstream CXCR4 signaling is regulated by K-Ras. 3) Aim III: Determine whether therapeutic targeting of CXCR4 prevents or abrogates progression of PanIN into pancreatic cancer in an in vivo murine PanIN model.

Public Health Relevance

Pancreatic cancer is a major cause of cancer-related deaths. Poor survival results from frequent recurrence after curative surgery and resistance to chemoradiation therapies. A better understanding of the pathogenesis of pancreatic cancer is clearly needed to improve clinical outcomes. The results of our proposed research studies can be applied to the prevention and/or treatment of human pancreatic disease.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Career Transition Award (K22)
Project #
5K22CA134637-03
Application #
8117218
Study Section
Subcommittee G - Education (NCI)
Program Officer
Jakowlew, Sonia B
Project Start
2009-09-18
Project End
2012-08-31
Budget Start
2011-09-01
Budget End
2012-08-31
Support Year
3
Fiscal Year
2011
Total Cost
$191,700
Indirect Cost
Name
City of Hope/Beckman Research Institute
Department
Type
DUNS #
027176833
City
Duarte
State
CA
Country
United States
Zip Code
91010
Heinrich, Eileen L; Arrington, Amanda K; Ko, Michelle E et al. (2013) Paracrine Activation of Chemokine Receptor CCR9 Enhances The Invasiveness of Pancreatic Cancer Cells. Cancer Microenviron 6:241-5
Kim, Joseph; Yip, M L Richard; Shen, Xiaoming et al. (2012) Identification of anti-malarial compounds as novel antagonists to chemokine receptor CXCR4 in pancreatic cancer cells. PLoS One 7:e31004
Heinrich, Eileen L; Lee, Wendy; Lu, Jianming et al. (2012) Chemokine CXCL12 activates dual CXCR4 and CXCR7-mediated signaling pathways in pancreatic cancer cells. J Transl Med 10:68