Angiogenesis is an essencial event in organ growth and tumor progression. Likewise, it has been shown that prostatic regression following androgen deprivation by castration is largely dependent on the behavior of endothelial cells. Indeed, endothelial cell death takes place much earlier than the epithelial cells in response to the testosterone drop. In this work we have investigated whether endothelial cell from the rat ventral prostate respond to soluble factors produced by both rat smooth muscle cells (SMC) and human epithelial tumor cells, testing the effect of conditioned culture medium and co-culturing. Endothelial cells (EC) were isolated by immunomagnetic procedure and cultured on plastic, collagen type I or matrigel. SMC were grown from explants in selective medium and tumor cell lineages PC-3 and LNCaP were obtained from ATCC. It was observed that the conditioned medium (1:3; v:v) from LNCaP, but not PC-3 and SMC stimulated the proliferation of endothelial cells grown in plastic.  On the other hand, the SMC, but not the tumor cells stimulated the proliferation of EC on matrigel. None of the cells showed significant effect on EC cultured on collagen substratum.  We have also investigated the effect of the same cell on the EC proliferation and death using co-culturing in transwells. In this culture condition, SMC, PC-3 and LNCaP had no effect on EC proliferation, but caused significant reduction in the number of apoptotic cells. Together, the results suggest the SMC and tumor cells produce proliferation and/or survival factors that control the behavior of EC in the rat ventral prostate. Funded by FAPESP and CNPq.