Knockdown of MMP2 or MMP9 or pretreatment with the MMP2/9 inhibitor BiPs inhibits IL-1β-induced GA cell migration and invasion in vitro. A: RT-PCR confirmed the efficiency of the MMP2 or MMP9 siRNAs, which significantly reduced MMP2 or MMP9 expression, respectively, by up to more than 75%. B: IL-1β increased GA cell migration and invasion in vitro; these effects were inhibited by MMP2 or MMP9 siRNA or the MMP2/9 inhibitor BiPs. **P < 0.05 vs. scramble siRNA (control siRNA)-transfected cells stimulated with IL-1β. Bars are the mean ± SD fold changes normalized to control group in the migration and invasion assays. C: Representative light microscopy images of AGS and MKN-45 cell migration and invasion in the Transwell migration and invasion assays.