Fig. 1.

Exogenous VEGF and conditioned media from Bcl-2 expressing prostate tumor cells induce endothelial cell proliferation and Bcl-2 expression. a Cell proliferation analysis (MTT assay) of non-treated control HMVEC cells and HMVEC cells treated for 4 days with 25 or 50 ng/ml VEGF and with media conditioned by either PC-3-Neo or PC-3-Bcl-2 cells. Each assay was performed in triplicate, and the mean for all three experiments was calculated. Cellular viability was confirmed by means of the Trypan blue exclusion test. (HUVEC cells subjected to exogenous VEGF or conditioned media from Bcl-2 expressing prostate cancer cells were noted to have an increase in proliferation, data not shown). b Bcl-2 transcript and protein expression in HMVEC cells treated with: A control media; B 50 ng/ml VEGF; C 50 ng/ml VEGF + 125 μg/ml bevacizumab; D PC-3-Neo conditioned media; E PC-3-Bcl-2 conditioned media; F PC-3-Bcl-2 conditioned media + 125 μg/ml bevacizumab. A:B, P < 0.05; A:E P < 0.05; B:C P < 0.05; E:F, P < 0.05. Results represent the mean of triplicates ± SD. The lower panel shows levels of Bcl-2 protein expression compared to that of tubulin by Western analysis (data not shown, HUVEC cells subjected to exogenous VEGF or conditioned media from Bcl-2 expressing prostate cancer cells were not found to over-express Bcl-2 at the RNA or protein level)