Abstract 200: EGCG inhibits pancreatic cancer stem cell characteristics in human primary tumors, and carcinogenesis in KrasG12D transgenic mice.

Abstract

Abstract EGCG, a component of green tea, exerts antiproliferative and proapoptotic actions on a number of different cancer cell lines through diverse mechanisms. However, the mechanisms by which EGCG inhibits cell proliferation and induces apoptosis are poorly understood. The objectives of this study were to examine the molecular mechanisms by which EGCG inhibits stem cell characteristics of pancreatic cancer stem cells (CSCs) derived from human primary tumors and carcinogenesis in KrasG12D transgenic mice. Human pancreatic CSCs (CD133+CD44+CD24+ESA+) are highly tumorigenic and form subcutaneous tumors in NOD/SCID IL2R gamma mice. Human pancreatic CSCs expressing high levels of CD133, CD24, CD44, ESA, and aldehyde dehydrogenase also express significantly more Nanog, Oct-4, Notch1, MDR1 and ABCG2 than normal pancreatic tissues and primary pancreatic cancer cells. Similarly, CSCs from KrasG12D mice express significantly high levels of pluripotency maintaining factors than pancreatic tissues from Pdx-Cre mice. EGCG inhibits the growth (size and weight) and development (PanIN lesions) of pancreatic cancer in KrasG12D mice by suppressing the activation of Kras, ERK, AKT and FoxO. EGCG inhibits the self-renewal capacity of pancreatic CSCs derived from human primary tumors and KrasG12D mice. EGCG inhibits pluripotency maintaining factors (Nanog, Sox-2, c-Myc and Oct-4) and drug resistance gene ABCG2 in CSCs. Inhibition of Nanog by shRNA enhances the inhibitory effects of EGCG on self-renewal capacity of CSCs. Finally, EGCG inhibits CSC's migration and invasion and markers of epithelial-mesenchymal transition (Zeb-1, Slug and Snail). These data suggest that EGCG can inhibit pancreatic cancer development in human and KrasG12D transgenic mice by inhibiting stem cell characteristics. In conclusion, EGCG can be used for the management of pancreatic cancer. Citation Format: Luke Marsh, Su-Ni Tang, Dara Nall, Chris Jackman, Sharmila Shankar, Rakesh K. Srivastava. EGCG inhibits pancreatic cancer stem cell characteristics in human primary tumors, and carcinogenesis in KrasG12D transgenic mice. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 200. doi:10.1158/1538-7445.AM2013-200