MAPK3 and glioblastoma: Importantly, cell proliferation and invasion analysis showed that blockade of Src or ERK1/2 with the inhibitors significantly reduced GBP5-promoted cell proliferation and invasion in U87 and U251 cells (Fig. 4B, C), suggesting that GBP5 promoted GBM aggressiveness via the Src/ERK1/2 MAPK/MMP3 pathway.