Figure 2-6914.

PlGF does not directly promote melanoma cell proliferation. A: Reverse transcription and real-time PCR was performed on total RNA extracted from B16-BL6 cells treated or not with rmPlGF for 3 hours. Results are expressed as relative fold induction of the VEGFR-1 mRNA in treated (+PlGF) versus untreated cells (C). B: Western blot analysis of cell extracts from B16-BL6 cells, treated or not with rmPlGF for 4, 12, and 24 hours was done by using a polyclonal antibody against the C-terminus of VEGFR-1. Bar and arrow highlight the VEGFR-1-related signal. HUVECs and M14 cells were used as positive and negative controls, respectively. Molecular weight marker is reported in kd. C: B16-BL6 proliferation assay. Cells were incubated with or without the indicated concentrations of rmPlGF in the presence or absence of 10 ng/ml of rmVEGF. HUVECs were used as a positive control in the same proliferation assay. Bars represent the mean of eight replicates ± SEM of a representative experiment. *P < 0.05 and **P < 0.001 versus untreated cells, unpaired Student’s t-test.