Effect of vascular endothelial growth factor C (VEGF-C) on the proliferation of FRH-0201 cholangiocarcinoma cells treated for different times, assessed by MTT assay. (A) The proliferation of cholangiocarcinoma cells treated with VEGF-C at concentrations of 1, 5, 10, 50 and 100 ng/ml for 24, 48 and 72 h, respectively; (B) The proliferation of cholangiocarcinoma cells treated with VEGF-C at concentrations of 1, 5, 10, 50 and 100 ng/ml for 24 h. Cell proliferation in the VEGF-C group was significantly different compared with that in the control group (*P<0.05, **P<0.01 vs. control), but the rate of increase in cell proliferation slowed when VEGF-C concentrations exceeded 10 ng/ml.