siRNA敲减缺氧诱导因子1α表达对口腔鳞癌细胞活力及癌胚抗原相关细胞黏附分子1表达的影响

目的:探究缺氧诱导因子1α(HIF-1α)与口腔鳞癌细胞活力和凋亡的关系以及作用机制。方法:采用RT-PCR和Western blot检测口腔鳞癌细胞系Tca8113和CAL27以及正常口腔上皮细胞NOK中HIF-1α和癌胚抗原相关细胞黏附分子1(CEACAM1)的mRNA和蛋白表达量; RNA干扰技术沉默口腔鳞癌CAL27细胞中HIF-1α的表达,实验分为空白对照组、无义对照组和siRNA-HIF1-α组,MTT实验检测敲减HIF-1α表达对细胞活力的影响,流式细胞术检测细胞凋亡率的变化,Western blot检测HIF-1α、P21、血管内皮生长因子(VEGF)、Bcl-2和Bax的蛋白水平。结果:HIF-1α和CEACAM1在口腔鳞癌细胞中的表达量显著高于正常口腔细胞(P 0. 05),且二者表达量呈正相关; HIF-1α和CEACAM1在CAL27细胞中的表达量显著高于Tca8113细胞(P 0. 05)。siRNA-HIF-1α组细胞中的HIF-1α蛋白表达量显著低于空白对照组(P 0. 05)。敲减HIF-1α表达显著抑制CAL27细胞的活力(P 0. 05),促进其凋亡(P 0. 05),显著增加P21和Bax的蛋白水平(P 0. 05),明显降低VEGF和Bcl-2的蛋白水平(P 0. 05)。结论:HIF-1α在口腔鳞癌中高表达,干扰HIF-1α的表达可显著抑制细胞的活力,促进其凋亡。这可能是通过调控HIF-1α下游靶基因的表达以及肿瘤血管的生成来发挥作用的。

Effect of hypoxia-inducible factor-1α knockdown by siRNA on viability and CEACAM1 expression in oral squamous cell carcinoma

AIM: To investigate the relationship between hypoxia-inducible factor-1α (HIF-1α) and viability and apoptosis of oral squamous cell carcinoma and its mechanism. METHODS: The expression of HIF-1α and carcinoembryonic antigen-related cell adhesion molecular 1 (CEACAM1) at mRNA and protein levels in oral squamous cell carcinoma cell lines Tca8113 and CAL27 and normal epithelial cell line NOK was determined by RT-PCR and Western blot. The expression of HIF-1α in CAL27 cells was silenced by RNA interference (RNAi) technique. The cells were divided into blank control group, non-sense control group and siRNA-HIF-1α group. The viability of CAL27 cells was measured by MTT assay and the apoptotic rate was analyzed by flow cytometry. The protein levels of HIF-1α, P21, vascular endothelial growth factor (VEGF), Bcl-2 and Bax were examined by Western blot. RESULTS: The expression of HIF-1α and CEACAM1 in oral squamous cell carcinoma cells was significantly higher than that in normal cells (P<0.05), and the expression of HIF-1α and CEACAM1 was positively correlated. The protein expression of HIF-1α in siRNA-HIF-1α group was significantly lower than that in blank control group (P<0.05). Knockdown of HIF-1α significantly inhibited CAL27 cell viability (P<0.05), promoted apoptosis (P<0.05), increased the protein levels of P21 and Bax (P<0.05), and significantly decreased the levels of VEGF and Bcl-2 (P<0.05). CONCLUSION: HIF-1α is over-expressed in oral squamous cell carcinoma. Knockdown of HIF-1α significantly inhibits cell viability and promotes apoptosis possibly through regulating the expression of HIF-1α downstream target genes and tumor angiogenesis.