Effect of integrin-linked kinase towards matrix metalloproteinase-9/tissue inhibitor of metalloproteinase-1 in the process of TGF-β1-induced epithelial-mesenchymal transition of renal tubular cell / 中国医师杂志

ABSTRACT

Objective To investigate the possible regulating effect of integrin-linked kinase (ILK) towards matrix metalloproteinase-9/tissue inhibitor of metalloproteinase-1 (MMP-9/TIMP-1) ratio in the process of transforming growth factor-β1 (TGF-β1)-induced epithelial-mesenchymal transition (EMT) in human kidney proximal tubular epithelial (HK-2) cells.Methods HK-2 cells were cultured and stimulated with 10 ng/ml TGF-β1.Specific ILK-small interfering RNA (ILK-siRNA) was used to inhibit ILK expression.The characteristic epithelial marker (E-cadherin) and mesenchymal marker (α-SMA) of EMT were examined by Real-time reverse transcription polymerase chain reaction (real-time RT-PCR) and Western blot.The expressions of ILK,MMP-9,and TIMP-1 were also examined,to determine the regulating effect of ILK towards MMP-9/TIMP-1 ratio.Results In the HK-2 cells cultured with TGF-β1,the expression of E-cadherin decreased,and α-SMA expression increased;overexpression of ILK and an abnormal changing of MMP-9/TIMP-1 ratio were observed.ILK inhibition by ILK-siRNA could adjust MMP-9/TIMP-1 ratio to near normal.Meanwhile,the overexpressed ILK and α-SMA were decreased.Conclusions Our data indicates that ILK-siRNA successfully inhibits ILK expression,which regulates the MMP-9/TIMP-1 ratio in HK-2 cells.The inhibition of ILK expression suppresses TGF-β1-induced EMT partially.