Influence Of Hypoxia On The Expression Of HIF-1α And GLUT-1 In Cervical Cancer Hela Cell And Its Relationship With The Cell Proliferation In Vitro

Objctive:To investigate the expression of hypoxia-inducible factor 1α(HIF-1α) and glucose transporter-1 (GLUT-1) in cervical cancer Hela cell line under hypoxia environment, and explore the relationship between hypoxia environment and the cell proliferation in vitro. We will discuss the mechanism of tumor cell proliferation which were accelerated by hypoxia in the mass of human cervical cancer, in order to provide ideas for a new target gene therapy which aims at hypoxia-inducible factor1α.Methods:Hypoxia environment of Hela cell line was induced by Chlorid hexahadrate CoCl2. MTT assay was used to test the effect of CoCl2-induced hypoxia environment on the growth activity of human cervical cancer Hela cell line in vitro. Reverse transcription polymerase chain reaction analysis and immunocytochemistry were used to determine the changes of hypoxia-inducible factor 1α(HIF-1α) and glucose transporter-1 (GLUT-1) in human cervical cancer Hela cell line in vitro under hypoxia. Agarose gel electrophoresis confirmed the specificity of the amplification product.Result:MTT results showed that the growth activity of human cervical cancer Hela cell line was enhanced when cells were cultured in 50μmol/L and 100μmol/L CoCl2 for 24 hours(P<0.05). And then,along with hypoxia prolonged, cell viability was decreased compared with the control group(P<0.05).The proliferation was inhibited by higher concentration of CoCl2(P<0.01). Quantitative real time RT-PCR results shows that the mRNA expression of HIF-1αafter hypoxia exposure for 72h was higher than that of control group(P <0.01). The mRNA expression of GLUT-1 was significantly increased after hypoxia exposure (P<0.05). Immunofluorescence analysis results showed that either normoxia or hypoxia, the expression of HIF-1αand GLUT-1 shows positive in human cervical cancer cell lines Hela. both the HIF-1αprotein and the GLUT-1 protein were increased in hypoxia conditions compared with the normoxia control group(P<0.01), Under hypoxic conditions, HIF-1αprotein increased to peak at 24 hours; GLUT-1 protein peaked at 48 hours with prolonged hypoxia.Conclusion:Acute or mild hypoxia conditions may promote human cervical cancer Hela cell line proliferation. Hypoxia conditions which was induced by CoCl2 can up-regulate the expressions of HIF-1αand GLUT-1 in human cervical cancer Hela cell line, Both of the two accelerated the growth of cervical cancer cell line Hela and leaded to hypoxia tolerance. The expression of GLUT-1 protein elevated later than HIF-1a protein suggested that GLUT-1 gene and protein expression was upregulated by HIF-1αprotein.