Song Ying, Wang Wenxia, Qu Xun, Sun Shanzhen
Department of Pathology, Stomatology College of Shandong University, Jinan, China.
Indian J Med Res. 2009 Feb;129(2):154-63.
BACKGROUND & OBJECTIVES: Hypoxia-inducible factor-1 alpha (HIF-1alpha) is a central transcriptional regulator of hypoxic response. Suppression of HIF-1alpha is important for exploring hypoxia-induced pathophysiological events. This study was carried out to analyze the hypoxia-induced changes of biological characteristics in the human tongue squamous cell carcinoma cell line Tca8113 and evaluate the effects of HIF-1alpha on the phenotype of the tongue squamous cell carcinoma.
HIF-1alpha gene was silenced with synthesized short interfering ribonucleic acids (siRNA). HIF-1alpha expression was measured on mRNA level by real-time reverse transcription (RT)-PCR and protein level by Western blot and immunofluorescence. The cell cycle and apoptosis of Tca8113 cells were analyzed by FACS. The proliferation and adhesion of Tca8113 cells were determined by MTT colorimetric assay.
Tca8113 could survive and showed a more aggressive phenotype under hypoxic condition. Exposure to hypoxia induced a prolonged elevation of HIF-1alpha protein and transfection of siRNA targeting HIF-1alpha (siRNA(HIF-1alpha)) reduced HIF-1alpha synthesis as measured on mRNA and protein level. Under normoxic or hypoxic conditions, treatment of Tca8113 cells with siRNA(HIF-1alpha) induced cell apoptosis and inhibited the growth and adhesion.
INTERPRETATION & CONCLUSION: siRNA(HIF-1alpha) could attenuate the tolerance against hypoxia in Tca8113 cells and inhibit their aggressive potential. Interfering with HIF-1alpha pathways by siRNA strategy may provide a therapeutic target for human tongue squamous cell carcinomas.
缺氧诱导因子-1α（HIF-1α）是缺氧反应的核心转录调节因子。抑制HIF-1α对于探索缺氧诱导的病理生理事件具有重要意义。本研究旨在分析缺氧诱导的人舌鳞状细胞癌细胞系Tca8113生物学特性的变化，并评估HIF-1α对舌鳞状细胞癌表型的影响。
用合成的小干扰核糖核酸（siRNA）沉默HIF-1α基因。通过实时逆转录（RT）-PCR在mRNA水平以及通过蛋白质印迹和免疫荧光在蛋白质水平检测HIF-1α的表达。通过流式细胞术分析Tca8113细胞的细胞周期和凋亡。通过MTT比色法测定Tca8113细胞的增殖和黏附。
Tca8113在缺氧条件下能够存活并表现出更具侵袭性的表型。暴露于缺氧环境会导致HIF-1α蛋白长时间升高，而转染靶向HIF-1α的siRNA（siRNA（HIF-1α））可降低mRNA和蛋白质水平上检测到的HIF-1α合成。在常氧或缺氧条件下，用siRNA（HIF-1α）处理Tca8113细胞可诱导细胞凋亡并抑制其生长和黏附。
siRNA（HIF-1α）可减弱Tca8113细胞对缺氧的耐受性并抑制其侵袭潜能。通过siRNA策略干扰HIF-1α途径可能为人类舌鳞状细胞癌提供治疗靶点。
