Effect of epidermal growth factor signal pathway on integrin alpha5 beta1 in prostate cancer cell line DU145 / 中华外科杂志

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the molecular mechanism of epidermal growth factor (EGF) signal pathway on the expression of integrin alpha5 beta1 in prostate cancer cell line DU145.</p><p><b>METHODS</b>Using flow-cytometry, the effects of EGF and the mitogen-activated protein kinase (MAPK) signal pathway inhibitor PD98059 on the expression of integrin alpha5 and beta1 subunits on DU145 cell surface were analyzed. RT-PCR and Western blot methods were used to examined the expression of mRNA and cell total protein of integrin alpha5 and beta1 subunits. And the metastatic phenotypes in DU145 cell were investigated.</p><p><b>RESULTS</b>The expression levels of integrin alpha5 beta1, which was the receptor for fibronectin, were changed. EGF up-regulated the protein and mRNA expression of beta1 subunit on DU145 cell surface, 231% and 248% (P < 0.01) compared to the control respectively, and it could significantly promote the ability of DU145 cell adhesion to fibronectin and migration. However PD98058, which was the inhibitor of MAPK signal pathway, down-regulated the protein and mRNA expression of beta1 subunit, 60% and 63% (P < 0.01) compared to the control respectively, and it had the contrary function on the adhesion and migration ability of DU145 cell. But both had no effect the expression of alpha5 subunit.</p><p><b>CONCLUSIONS</b>EGF might promote the metastatic ability mainly by up-regulating the expression of beta1 subunit by activating MAPK signal pathway in DU145 cells. Their regulation effects are on the mRNA transcriptional level.</p>