Effect of HMGB1 expression knockdown on invasion ability of breast cancer cells induced by TNF-α / 中国病理生理杂志

ABSTRACT

AIM:To investigate the effect of high-mobility group box-1 (HMGB1) expression knockdown on the invasion ability of breast cancer cells induced by tumor necrosis factor-α (TNF-α).METHODS:HMGB1 siRNA was used to transfect into the breast cancer MDA-MB-231 cells.The expression of HMGB1 at mRNA and protein levels was determined by RT-qPCR and Western blot.After the MDA-MB-231 cells with HMGB1 expression knockdown were treated with TNF-α, the apoptosis rate was analyzed by flow cytometry, the cell invasion ability was measured by Transwell assay, and the cell migration ability was detected by cell scratch test.The protein expression of E-cadherin, MMP-2, N-cadherin, MMP-9 and Bax was determined by Western blot.RESULTS:The expression of HMGB1 at mRNA and protein levels in the MDA-MB-231 cells transfected with HMGB1 siRNA was significantly lower than that in the non-transfected cells (P<0.05).The apoptosis rate in the cells was increased after TNF-αtreatment, and the cell invasion and migration abilities were also increased.The protein level of E-cadherin in the cells was decreased, the protein level of N-cadherin was increased, and the protein levels of MMP-2, MMP-9 and Bax were also increased (P<0.05).After the MDA-MB-231 cells with HMGB1 expression knockdown were induced by TNF-α, the apoptotic rate was increased, the invasion and migration abilities were decreased, the protein levels of E-cadherin and Bax were increased, and the protein levels of N-cadherin, MMP-2 and MMP-9 were decreased, as compared with the cells only induced by TNF-αwithout knockdown of HMGB1 expression (P<0.05).CONCLUSION:Knockdown of HMGB1 expression enhances the apoptosis of breast cancer cells induced by TNF-α, and inhibited the cell invasion, migration and epithelial-mesenchymal transition induced by TNF-α.The mechanism may be related with the changes of protein expression of MMP-2, MMP-9 and Bax.