Inhibitory effect of salinomycin on human breast cancer cells MDA-MB-231 proliferation through Hedgehog signaling pathway

Abstract

To investigate the inhibitory effect of salinomycin on human breast cancer cells in vitro, and to explore the related molecular mechanism. Human breast cancer MDA-MB-231 cells were treated with salinomycin at different concentrations and at various time points. The effect of salinomycin on MDA-MB-231 cells proliferation was studied by CCK-8 method. The cell cycle status was examined by flow cytometry. RT-PCR and Western blot were used to detect the expression of Shh, Smo and Gli1 in the Hedgehog pathway at mRNA and protein levels. Proliferation of MDA-MB-231 cells treated with salinomycin was markedly inhibited in a concentration and time dependent manner. Salinomycin at concentrations of 0, 0.4, 0.8 and 1.6 µmol/L inhibited the growth at the rates of 11.18%, 25.88%, 50.03%, 92.65%, respectively. Salinomycin prevented MDA-MB-231 cells from G1 into S phase. Salinomycin at concentrations of 0, 0.8 and 1.6 µmol/L resulted in S-phase percentage of 25.03%, 11.85% and 35.21%, respectively (P < 0.05). RT-PCR and Western blot showed that the expression of key elements Shh, Smo and Gli1 in the Hedgehog pathway was inhibited by salinomycin in a concentration dependent manner (P < 0.05). Salinomycin prevents breast cancer cell transition from G1 to S phase through downregulation of the target genes of Hedgehog signaling pathway, leading to an effective inhibition of MDA-MB-231 cells.