Abstract A91: Stage-specific transcriptome analysis of human pancreatic cancer progression

Abstract

Abstract Our goals are to discover gene networks that control the progression of pancreatic intraepithelial neoplasias (PanINs) to invasive stage pancreatic ductal adenocarcinoma (PDAC) and to understand how the pluripotency regulatory network can temporarily suppress the transition. Certain cancer cells are amenable to reprogramming to pluripotency by somatic cell nuclear transfer (SCNT) or defined transcription factors (iPS). Prior work showed that SCNT-cancer cells develop into normal appearing blastocysts, but later the cancer genome in SCNT-chimeric mice was reactivated during embryogenesis, re-expressing the cancer phenotype of the lineage from which they originated. We previously showed that when an iPS-like line, designated 10-22, derived from human pancreatic ductal adenocarcinoma (PDAC), was injected into immunodeficient mice, they consistently recapitulated pre-invasive, PanIN to invasive stages of PDAC (Kim et al., 2013 Cell Reports). Specifically, the PDAC-iPS cells differentiated into a ductal, PanIN2/3 epithelium with a collagen basement membrane, followed by progression to an invasive stage phenotype with basement membrane breakdown. Furthermore, the ductal cell lesions were surrounded by stroma that co-differentiated from the pluripotent 10-22 cells, indicative of signaling interactions with the epithelium. With this system, we now ask: 1) What gene regulatory networks for pluripotency can transiently attenuate the cancer genome; 2) Upon loss of pluripotency and differentiation, what are the regulatory network transitions during human PDAC progression? 3) What are the reciprocal signals between the PDAC epithelial cells and their surrounding stromal cells during pancreatic cancer progression? To address these questions, we have genetically tagged the PDAC-iPS 10-22 line with a lentiviral vector expressing a ubiquitous promoter driving GFP and a ductal K19 promoter driving infrared protein (iRFP), so that cells can be retrieved by FACS. While GFP+iRFP- cells include stroma derived from the 10-22 cells, GFP+iRFP+ allows isolation of precursor and invasive stages of PDAC. The tagged lines were injected into immunodeficient mice, the lesions were monitored in vivo by iRFP flourescence, and RNA was isolated in triplicate at multiple time points and subjected to RNA-Seq analysis. The human PDAC 10-22 cell system is being used to discover effectors and networks whereby pluripotency can dominate over cancer and new features of human PDAC progression, which would be ultimately used for developing novel cancer therapies. Citation Format: Jungsun Kim, Greg Donahue, Wenli Yang, Kenneth S. Zaret.{Authors}. Stage-specific transcriptome analysis of human pancreatic cancer progression. [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer: Advances in Science and Clinical Care; 2016 May 12-15; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2016;76(24 Suppl):Abstract nr A91.