VEGF signal transduction in MM cells. VEGF mediates MM cell proliferation via MEK-1/ERK signaling and MM cell survival via up-regulation of survivin and Mcl-1. VEGF-induced MM cell migration on fibronectin is dependent on the localization of VEGFR-1 within caveolae, followed by Src tyrosine kinase family–dependent phosphorylation of caveolin-1, PI3-kinase, and PKCα.