Tanshinone IIA suppresses gastric cancer cell proliferation and migration by downregulation of FOXM1

Tanshinone IIA (TSN) exhibits a variety of anticancer effects. However, whether it inhibits gastric cancer (GC) cell proliferation and migration and the mechanism remain unclear. In the present study, different concentrations of TSN were co-incubated with SGC-7901 cells. The pcDNA-FOXM1 or FOXM1-siRNA plasmid was transfected into cells before treatment with 5 µg/l TSN. The proliferation and migration abilities of the SGC-7901 cells were tested by MTT and wound healing assays. Western blotting was used to investigate the expression levels of P21, Ki-67, PCNA, MMP-2, MMP-9 and FOXM1. We found that compared with the control, the proliferation and migration abilities of the SGC-7901 cells were decreased after incubation with different concentrations of TSN in a dose-dependent manner (p<0.01). Moreover, the expression levels of Ki-67, PCAN, MMP-2, MMP-9 and FOXM1 were decreased, and P21 was increased in the TSN-treated SGC-7901 cells (p<0.01). In addition, downregulation of FOXM1 by FOXM1-siRNA had the same effect as TSN on SGC-7901 cells, and overexpression of FOXM1 partly abrogated TSN-mediated inhibition of SGC-7901 cell proliferation and migration. These results suggested that TSN inhibits SGC-7901 cell proliferation and migration by downregulation of FOXM1.