G3BP is a RasGAP binding protein that is overexpressed in many human cancers. We 
previously reported that downregulation of G3BP suppressed cell growth and 
induced apoptosis in HCT116 cells. Here we report that both transient and stable 
knockdown of G3BP suppressed the growth, migration and invasion capability of 
human lung carcinoma H1299 cells. Moreover, downregulation of G3BP significantly 
inhibited the phosphorylation of Src, FAK and ERK, and the levels of NF-κB were 
also markedly decreased in H1299 cells. Knockdown of G3BP also decreased the 
expression of matrix metalloproteinase-2 (MMP-2), MMP-9 and plasminogen 
activator (uPA), and in vivo data demonstrated that downregulation of G3BP 
markedly inhibited the growth of H1299 tumor xenografts. Together, these data 
revealed that knockdown of G3BP inhibited the migration and invasion of human 
lung carcinoma cells through the inhibition of Src, FAK, ERK and NF-κB and 
decreased levels of MMP-2, MMP-9 and uPA.