Objective To study the effects of factors secreted by mouse embryonic stem cells( ESC) on the biological characteristics of prostate cancer cells RM-1 and to explore the mechanism. Methods A non-contact co-culture system was established with Transw ell chambers in vitro. The chambers connecting ESC combined with mouse embryonic fibroblasts( MEF) and RM-1 cells served as experimental group,while the chambers connecting MEF and RM-1 cells were negative controls. After cells were co-cultured for 72 h,the proli...