RESUMO
The present study was carried out to investigate the effects of vascular endothelial growth inhibitor 174 (VEGI174) and its functional domains (V7 and V8) on epithelialmesenchymal transition (EMT) in renal cell carcinoma (RCC) cells in vitro. The RCC cell lines A498 and 786O were used in this study. Based on our preliminary study, we selected fulllength VEGI174 and its functional domains (V7 and V8) as the target genes in this study. Plasmids containing VEGI174, V7 or V8 transgenes were constructed and transfected into A498 and 786O cell lines. Cytological activity was tested during cell culture. Quantitative PCR and western blot analysis were performed to determine the expression levels of EMT markers (Ecadherin, vimentin, ßcatenin and Slug). Overexpression of VEGI174, V7 or V8 did not have a significant influence on cell viability (P>0.05). The mRNA level of Ecadherin was significantly upregulated, while that of vimentin was downregulated in A498VEGIexp, A498V7exp, A498V8exp, 786OVEGIexp, 786OV7exp and 786OV8exp cells compared with the cells containing the empty plasmid controls (P<0.05). The western blot results showed that changes in protein expression levels were consistent with the changes in mRNA expression. Both the mRNA and protein expression levels of ßcatenin and Slug were downregulated in the A498VEGIexp, A498V7exp, A498V8exp, 786OVEGIexp, 786OV7exp and 786OV8exp cells. In conclusion, overexpression of VEGI174, V7 or V8 inhibited EMT in A498 and 786O cells. Notably, V7 and V8 are two effective functional domains of VEGI174 that have the potential to be studied for peptide synthesis and the treatment of RCC.