Bortezomib suppresses renal tubular epithelial-mesenchymal transition induced by TNF-α through downregulation of Smurf2 in HK-2 cells / 中华器官移植杂志

ABSTRACT

Objective To investigate the effect of Bortezomib on renal tubular epithelialmesenchymal transition (EMT),and to determine whether Smad ubiquitin regulatory factor 2 (Smurf2) expression induced by tumor necrosis factor-α (TNF-α) can be reversed by Bortezomib in human renal tubular epithelial cells (HK-2).Methods The HK-2 cells were divided into control group (cultured with fetal bovine serum),TNF-α group (cultured with TNF-α),Bortezomib group (cultured with Bortezomib) and experimental group (treated with Bortezomib and TNF-α together).Each group of cells was observed under an inverted microscope,and then the cells of each group were collected.RT-PCR and Western blotting were performed to detect the expression levels of fibronectin (FN),Smurf2,E-cadherin and α-smooth muscle actin (α-SMA).Results As compared with the TNF-α-treated group,the morphology of HK-2 cells was still cobblestone-like after intervention with bortezomib;however,the cellular morphology did not change significantly in the bortezomib-treated group as compared with the control group.As compared with the control group,the expression of FN mRNA and protein in the TNF-α group was significantly increased (P＜0.05).As compared with the TNF-α group,bortezomib inhibited the expression of FN induced by TNF-α (P＜0.05) There was no significant difference in the expression of FN between bortezomib-treated group and control group (P ＞0.05).As compared with the control group,E cadherin was significantly decreased in HK-2 cellsafter treatment with TNF-α,and α-SMA was significantly increased (P＜0.05).As compared with TNFα group,co-stimulation with bortezomib reversed the expression of E cadherin and α-SMA induced by TNF-α (P ＜ 0.05),but the expression of E-cadherin and α-SMA did not change significantly in the bortezomib-treated group as compared with the control group (P ＞ 0.05).As compared with the control group,TNF-α could increase the expression of Smurf2 mRNA and protein (P＜0.05),and bortezomib could inhibit the increase in Smurf2 induced by TNFα (P＜0.05).As compared with the control group,the expression of Smurf2 did not change significantly in the bortezomib-treated group (P＞0.05).Conclusion Bortezomib can antagonize the expression of Smurf2 and EMT induced by TNF-α in HK-2 cells.