摘要
目的探讨缺氧诱导因子1α(HIF-1α)和基因系尾型同源盒基因2(CDX2)在人结肠癌细胞株SW480和LS174T不同缺氧时间的表达及其可能的作用机制。方法(1)MTT方法检测在不同CoCl2浓度(100,150,200μmol/L)下和不同时点(24,36,48 h)时对SW480和LS174T细胞活力以及增殖的影响,筛选适宜的CoCl2作用浓度。(2)在细胞化学缺氧培养相应时段,采用半定量RT-PCR技术检测HIF-1α,Snail和CDX2的mRNA的表达变化;同时采用Western blotting技术检测CDX2的蛋白表达。结果结肠癌细胞株在不同浓度CoCl2环境下随缺氧时间的延长,细胞活力明显受到抑制。在低浓度CoCl2(100μmol/L)干预下,随着缺氧时间的延长,HIF-1α和Snail mRNA表达逐渐上升,缺氧24 h时达到高峰,CDX2 mRNA及蛋白表达水平逐渐下降。结论缺氧诱导HIF-1α过表达可通过下调CDX2而加速结直肠癌的进展。
Objective To investigate the mechanisms and relationship between HIF-1α and CDX2 expressions in human colonic cancer cell line SW480 and LS 174 T during different time of hypoxia. Methods （ 1 ）The two tumor cell lines （ SW480 and LS174T） were respectively exposed to CoCl2 （ 100,150 and 200 μmol/ L） for different time periods （24 h ,36 h and 48 h） , and cells viability and proliferation were detected by MTT methods in order to select suitable CoCl2 concentration. （2） Semiquantitative RT-PCR were used to detect the change in mRNA level of SW480 and LS174T under CoCl2 （100μmol/L）. Total amounts of CDX2 protein in SW480 and LS174T were examined by Western blot. Results Higher concentrations of COCl2（150, 200μmol/L） significantly decreased cell survival rate （P 〈 0. 05 ）. So, we selected low concentration of CoCl2 （100 μmol/L） to construct hypoxic model. HIF-1α mRNA expression of SW480 and LS174T increased with prolongation of hypoxia time when cells were exposed to CoCl2 （100αmol/L） and reached peak at 24 hours hypoxia （ P 〈 0.05 ）. Similar results were observed in Snail mRNA expression. But mRNA and protein expression of CDX2 reduced significantly under CoCl2 （100μmol/L） and gradually declined as the time of hypoxia was prolonged. Conclusions HIF-1α might be up-stream regulator of CDX2 and its over expression may play an important role in progression of colorectal cancer.
出处
《中国普通外科杂志》
CAS
CSCD
北大核心
2010年第4期364-368,共5页
China Journal of General Surgery
基金
国家自然科学基金资助项目(30672070
30400430)
陕西省科学技术研究发展计划项目(2009K12-01)
