Differential Inductive Signaling of CD90 Prostate Cancer-Associated Fibroblasts Compared to Normal Tissue Stromal Mesenchyme Cells.

UNLABELLED: Prostate carcinomas are surrounded by a layer of stromal fibroblastic cells that are characterized by increased expression of CD90. These CD90(+) cancer-associated stromal fibroblastic cells differ in gene expression from their normal counterpart, CD49a(+)CD90(lo) stromal smooth muscle cells; and were postulated to represent a less differentiated cell type with altered inductive properties. CD90(+) stromal cells were isolated from tumor tissue specimens and co-cultured with the pluripotent embryonal carcinoma cell line NCCIT in order to elucidate the impact of tumor-associated stroma on stem cells, and the 'cancer stem cell.' Transcriptome analysis identified a notable decreased induction of smooth muscle and prostate stromal genes such as PENK, BMP2 and ChGn compared to previously determined NCCIT response to normal prostate stromal cell induction. CD90(+) stromal cell secreted factors induced an increased expression of CD90 and differential induction of genes involved in extracellular matrix remodeling and the RECK pathway in NCCIT. These results suggest that, compared to normal tissue stromal cells, signaling from cancer-associated stromal cells has a markedly different effect on stem cells as represented by NCCIT. Given that stromal cells are important in directing organ-specific differentiation, stromal cells in tumors appear to be defective in this function, which may contribute to abnormal differentiation found in diseases such as cancer. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s12307-010-0061-4) contains supplementary material, which is available to authorized users.