Objective: To investigate whether hepatitis B x protein (HBx) stimulates vascular endothelial growth factor (VEGF) through hypoxia inducible factor-1 (HIF-1 alpha) pathway.
Methods: Two plasmids including pIRES-EGFP-HBx and pTK-Hyg were co-transfected to a hepatocellular carcinoma cell line SMMC-7721. With fluorescence-positive and fluorescence-negative hygromycin-resistant colonies selected, expressions of VEGF and HIF-1 alpha in protein or/and mRNA level were detected.
Results: Fluorescence-positive cells were stably integrated with HBx, in which expression of HIF-1 alpha and VEGF were upregulated. Fluorescence-negative cells did not express HBx, VEGF or HIF-1 alpha.
Conclusion: HBx can activate VEGF through HIF-1 alpha pathway.