Figure 2

Mitogenic and survival effect of L-lactate. A) Proliferation assay in prostate cell lines cultured for 48 h in decreasing glucose concentrations (1, 0.6, 0.2, 0 g/L) and in presence or not of 5 mM L-lactate (lac). Cells cultured in 0.6 g/L glucose without L-lactate were chosen as reference (100%). B) LNCaP cells were cultured at low density for 2 weeks in decreasing glucose concentrations (0.6, 0.2, 0 g/L) in presence or not of 5 mM L-lactate (lac). At the endpoint the number of colonies and the total area covered by cells were evaluated. Representative images from LNCaP cells cultured in 0.2 g/L glucose are reported. Data represent mean values ± SD from at least three independent experiments. C) Western blot analysis of MCT1 in whole cell lysate from PCa cell lines, LNCaP and PC3, and from transformed epithelial cell lines, RWPE-1 and WPE1. Beta-actin detection was utilized as loading control. *P < 0.01 according to Student’s t test.