RESUMEN
Objective To investigate the regulatory effect of TNF-α on netrin-1 expression and the related mechanism. Methods The expression of netrin-1 was examined by RT-PCR and Western blotting analysis in HEK-293 cells treated with TNF-α. The netrin-1 gene promoter was amplified by PCR and was cloned into pGL3 basic vector. Then the purified pGL3-netrin-1-promoter was transfected into HEK-293 cells, the luciferase activity of netrin-1 gene promoter was detected by luminometer, and the regulatory effect of TNF-α on netrin-1 expression was observed. Results It was confirmed that TNF-α increased expression of netrin-1. pGL3-netrin-l-promoter vector was successfully constructed as confirmed by sequencing. The pGL3-netrin-l-promoter vector was confirmed to have the promoter activity as confirmed by the luciferase system. The activity of netrin-1 promoter was increased significantly in HEK-293 cells after treated with TNF-a (P<0. 05), and the increase was in a time-and concentration-dependent manner. Conclusion TNF-α can regulate netrin-1 expression through modulating netrin-1 promoter activity.