Abstract: Objective To investigate the effect of hypoxia inducible transcription factor 1α(HIF-1α) on proliferation of rectal cancer HT-29 cells and to clarify its mechanism.Methods The wild type HT-29 cells(Wt-HT-29) and Si-HT-29 cells transfected with HIF-1α small interfering RNA  were cultivated  under normoxia and hypoxia conditions.The expressions of HIF-1α and hexokinase-Ⅱ(HK-Ⅱ) under normoxia and hypoxia conditions were detected by using Western blotting method．The survival rates of cells in various groups were detected by using MTT method.Furthermore，theATP content was detected by using ATP Kit.Results Western blotting showed that the  expressions of HIF-1α and HK-Ⅱ in Wt-HT-29 cells were higher than those in  Si-HT-29 cells under hypoxia condition. The amount of ATP and the number of  wild-type cells generated under normoxic conditions were regarded as 100%.The percentages of the ratios of the amount of ATP and the number of Si-HT-29 cells under normoxia condition and the amount of ATP and the number of the two cell lines under hypoxia condition to the  amount of ATP and  the number of  Wt-HT-29 cells under normoxia condition were regarded as the respective amount of ATP and the surrival rate of cells.Under normoxia condition the ATP amount and cell survival rate of HT-29 cels were 93.6% and 92.0%， respectively；and there  was no significant difference compared with Wt-HT-29 cells (P> 0.05).But under hypoxia condition the survival rates  of Wt-HT-29 cells  and Si-NT-29  cells were 85.0% and 61.3%，respectively,and there was significant difference(P<0.05).At the same time the ATP amounts  of Wt-HT-29 cells and Si-HT-29 cells were 81.2% and 42.9%,respectively;and  significant difference was observed (P<0.05).Conclusion HIF-1α can improve ATP production of rectal cancer cells by inducing HK-Ⅱ expression to increase the proliferation,and it may become a new therapy target of rectal cancer.

Key words:  , hypoxia inducible transcription factor 1&, alpha, rectal neoplasms, adenosine triphosphate, hypoxia