Abstract 4351: Targeting miRNA-driven aggressive behavior of pancreatic cancer stem cells by a novel drug

Abstract

Abstract Pancreatic cancer (PC) is a lethal malignant disease, which is in part due to lack of early detection biomarkers. Once diagnosed, the majority of PC patients are already in advanced stages. Currently there are no effective treatments in improving the overall survival. Therefore, the majority of PC patients die within 5-6 months due to therapeutic resistance and early metastatic disease. Recently, a sub-population of cancer stem cells (CSCs) (<0.1%) have been identified from many different tumors including PC, and these cells are believed to be responsible for treatment resistance, tumor recurrence and metastasis. Many studies have shown that the existence of CSCs has important clinical implications because CSCs are involved in cell migration/invasion, drug resistance, and metastasis, which leads to poor clinical outcome. Therefore, selective killing or complete elimination of CSCs by novel approaches would likely become newer treatment strategy for PC in the improvement of overall survival. However, the regulation of CSC characteristics during tumor development and progression has not been well understood. In this study, cell and molecular biology techniques were used to investigate the CSC characteristics and its regulation to find a new effective approach for the treatment of PC. We found that cancer stem-like cells (CSLCs) which is reminiscent of CSCs isolated from human PC cell line, MiaPaCa-2 cells as triple-marker positive cells (CD44+/CD133+/EpCAM+ cells) cells displayed aggressive phenotypes, such as increased clonogenicity, cell migration, and self-renewal capacity, along with over-expression of CSC marker microRNAs (miRNAs) such as miR-21 and miR-210. Under-expression of miR-21 and miR-210 by transfection of anti-miRNAs led to decreased clonogenicity, cell migration and self-renewal capacity, along with reduced expression of CSC-associated markers/mediators such as CD44, EpCAM, EZH2, Notch-1, and Snail in CSLCs. Similarly, under-expression of CSC-associated mediator Notch-1 led to decreased cell migration, self-renewal capacity, and expression of EpCAM and Snail in CSLCs. Finally, CDF, a novel synthetic small molecule showed reduced aggressive behavior of CSLCs such as cell survival/growth, migration, clonogenicity, self-renewal capacity, and decreased expression of miR-21 and miR-210. From these results, we conclude that CDF may serve as an effective anti-tumor agent via targeting miRNA-driven aggressive behavior of CSLCs. Citation Format: Evan Bao, Asfar Azmi, Ellen Zhang, Shadan Ali, Aamir Ahmad, Feras Zaiem, Bin Bao, Fazlul H. Sarkar. Targeting miRNA-driven aggressive behavior of pancreatic cancer stem cells by a novel drug. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4351. doi:10.1158/1538-7445.AM2014-4351