Abstract 4277: Comparative gene expression analysis of proliferating stromal cells from pancreatic ductal adenocarcinoma, pancreatitis and normal pancreas (2012)

Abstract Introduction: Stromal cells associated with cancer cells are considered an important component of tumor microenvironment of pancreatic cancer. The intratumoral desmoplasia characteristic of pancreatic cancer is a result of growing carcinoma paracrine action on surrounding normal tissue cells. Selective targeting of tumor stroma cells can markedly increase the effectiveness of currently used chemotherapeutic agents against pancreatic cancer. Therefore, a search for new targets in stromal cells is an important part of developing new combined therapies of this disease. Our work was aimed at comparative studying of gene expression in stromal cells of normal pancreas, pancreatitis and pancreatic ductal adenocarcinoma tissues. Methods: Cultured stromal cells were obtained from samples of normal pancreatic (n=3), pancreatitis (n=3) and ductal adenocarcinoma tissues (n=4). The cell cultures obtained were preliminary characterized by immunofluorescence, RT-PCR and western blotting. A full genome gene expression analysis was performed using a modified SAGE technique. Expression of selected dysregulated genes was analyzed by quantitative PCR. Results: Morphological and immunofluorescent analyses of the obtained primary stromal cultures indicated that they could be assigned to pancreatic stellate cells (PSC). The SAGE analysis allowed to quantitatively estimate expression of 9860 genes in normal PSC, 8744 PSC genes in pancreatitis, and 9311 genes in tumor PSC. A comparison of normal and tumor PSC revealed statistically significant (P&lt;0.001) differences in expression of 270 genes. Of them, 146 genes were upregulated and 124 genes downregulated in tumor PSC as compared to normal PSC. An expression analysis of selected dysregulated genes by RT-PCR detected changes in the activity of some genes involved in tumor progression of pancreatic cancer. In particular, the genes of two chemokines (CXCL12 and CX3CL1) and the JAG1 Notch ligand were upregulated in tumor PSC. A similar comparison of tumor PSC and PSC from pancreatitis tissue detected 68 differentially expressed genes (P&lt;0.001), 40 of which were upregulated and 28 downregulated in tumor PSC as compared to pancreatitis PSC. Expression of 23 genes was upregulated in tumor PSC as compared with PSC both from pancreas and pancreatitis. On the whole, the expression profile of tumor PSC was markedly more similar to that of PSC from pancreatitis tissues than from normal PSC. Conclusions: The results obtained in our work revealed statistically significant changes in the expression of some PSC genes in stroma of ductal pancreatic adenocarcinoma as compared to normal PSC. The similarity of tumor and pancreatitis PSC expression profiles may suggest mutual mechanisms of forming the fibrous tissue of pancreatitis and tumor stroma of pancreatic carcinomas. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4277. doi:1538-7445.AM2012-4277