HIF-1α regulated tongue squamous cell carcinoma cell growth via regulating VEGF expression in a xenograft model.

OBJECTIVE:We aimed to study the mechanism of hypoxia-inducible factor 1 alpha (HIF-1α) regulating the cell proliferation of tongue squamous cell carcinoma (TSCC) via vascular endothelial growth factor (VEGF). METHODS:We used RNA interference (RNAi) technique, transfected chemically synthesized siRNA against HIF-1α into CAL-27 cells, and detected the expression of HIF-1α and VEGF by real time-PCR and Western blotting in order to find out if HIF-1α regulated the expression of VEGF. A xenograft experiment was carried out to observe the role of HIF-1α on the tumor growth of tongue squamous cell carcinoma. RESULTS:HIF-1α and VEGF mRNA expression was significantly downregulated 36 and 48 h after transfection (P<0.05); the protein expression of HIF-1α and VEGF was also significantly suppressed by siRNA against HIF-1α. Furthermore, intratumoraly injection of HIF-1α targeting siRNA suppressed tumor growth in nude mice. CONCLUSIONS:HIF-1α regulated VEGF expression, and they may contribute to TSCC cell tumor growth.