Role of pericytes as cancer associated fibroblasts

© 2013 Dr. Lynn ChongCancer associated fibroblasts (CAFs) are a heterogeneous population of cells with a broadly similar phenotype, but with the common ability to promote cancer growth. In this report, we have specifically studied the role of a particular stromal cell type: the pericyte, in cancer progression. Pericytes are well-known to stabilise blood-vessel endothelial cell function both during homeostasis and tumour-associated angiogenesis. Here, we demonstrate a novel role for these cells as cancer-associated fibroblasts. Specifically, ovarian cancer patients carrying the pericyte gene signature are predisposed to having a higher risk of relapse and lower overall survival suggesting that pericyte involvement is a strong predictor of recurrent cancer and mortality. Importantly this high risk patient group was distinct from the groups identified by an angiogenic signature suggesting a more direct role for pericytes in increasing tumour growth. Consistent with this, co-injection of an ovarian cancer cell line (OVCAR-5), with pericytes resulted in accelerated tumour- forming ability in vivo. Pericytes were also able to enhance the intrinsic migratory and invasive capacity of OVCAR-5 cells in vitro. Taken together, these results suggest that CAFs can originate from pericytes and the genes they express may be useful prognostic tools in predicting patient survival. Current work is aimed at identifying the cellular and molecular events by which pericytes contribute to tumour development. The data obtained will assist in developing potential targets for anti-cancer therapy