Abstract 2264: Lumican as a new target to develop molecularly-targeted drugs for pancreatic cancer

Proceedings: AACR 101st Annual Meeting 2010‐‐ Apr 17‐21, 2010; Washington, DC Background: Lumican is a member of a small leucine-rich proteoglycan family and its overexpression has been reported in breast, colorectal, neuroendocrine cell, uterine cervical and pancreatic cancers. The expression of lumican in stromal tissues in breast cancer is associated with a high tumor grade, a low estrogen receptor expression level, and young age. Lumican expression in the cytoplasm in advanced colorectal cancer is correlated with a poor prognosis. Lumican expression was previously reported in pancreatic cancer, but the role of lumican in pancreatic cancer is still not well understood. In this study, we clarified the role of lumican in pancreatic cancer. Methods: Immunohistochemical analysis using anti-lumican antibody was performed in 65 pancreatic cancer patients. Lumican mRNA and protein were examined in pancreatic cancer cell lines (i.e. PANC-1, MIA PaCa-2, KLM-1) by real-time PCR and western blot. Lumican stably transfected PANC-1 cells were prepared. Then, the growth rates in vitro and in vivo were compared with mock cells. The lumican expression of PANC-1 cell was knocked down using siRNA. Then, the growth rate in vitro was compared with the control cell. Results: Immunohistochemically, lumican was localized in the cytoplasm of cancer cells in 33 of 65 patients (51%). Lumican expression in cancer cells did not correlated with clinicopathological factors. However, the survival rate of patients with lumican-positive cancer cells was significantly lower than those with lumican-negative cancer cells in the surgery-only group. Lumican mRNA and the protein were detected in all pancreatic cancer cell lines and PANC-1 cells expressed median level of lumican in the cancer cell lines examined. The growth rate of lumican-transfected PANC-1 cells was significantly higher than that of mock cells both in vitro and in vivo. Moreover, the growth rate of lumican-knocked down PANC-1 cell was significantly lower than that of the control cell. Conclusion: Lumican might regulate pancreatic cancer cell growth and become a new target to develop anti-cancer drug for pancreatic cancer patients. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2264.