缺氧对DEC1在肝癌细胞中表达的影响

Expression of DEC1in hepatocellular carcinoma cell lines and effect of hypoxia

目的探讨肝癌中分化型胚胎软骨发育基因1(differentiated embryo-chondrocyte expressed gene 1,DEC1)的表达水平,并评价缺氧对其表达的影响。方法选取人正常肝细胞系QSG-7701及肝癌细胞系BEL-7402、SMMC-7721,分别进行正常氧培养和缺氧培养(0、2、4、6、24和48 h),用RT-PCR和western blot检测各组缺氧诱导因子1α(hypoxia-inducible factor-1α,HIF-1α)、DEC1 mRNA及蛋白质的水平,并进行相关性分析。结果正常氧培养时,BEL-7402、SMMC-7721细胞DEC1 mRNA和蛋白质表达均明显高于QSG-7701细胞(P均<0.01)。不同时相缺氧时HIF-1αmRNA表达无明显变化(F=1.995,P>0.05),但随缺氧时间延长,HIF-1α蛋白、DEC1 mRNA及DEC1蛋白表达显著增加(F分别为18.950、92.567和15.775,P均<0.01)。HIF-1α蛋白与DEC1 mRNA及DEC1蛋白的表达均呈正相关(r分别为0.885、0.826,P均<0.05)。结论 DEC1在人肝癌细胞中高表达,缺氧可诱导肝癌细胞中DEC1表达升高。

Objective To investigate the expression of differentiated embryo-chondrocyte expressed gene1（DEC1） in hepatocellular carcinoma cell lines and estimate the influence of hypoxia on DEC1 expression.Methods Normal liver cell line QSG-7701 and two HCC cell lines,i.e.,BEL-7402 and SMMC-7721,were cultured for 0,2,4,6,24 and 48 hours under the conditions of normoxia and hypoxia respectively.The levels of mRNA and protein of hypoxia-inducible factor-1α（HIF-1α） and DEC1 were determined by RT-PCR and western blot and their correlations were analyzed.Results The expressions of both mRNA and protein of DEC1 in HCC cell lines were upregulated significantly compared with those in QSG-7701 cell line（P＆lt;0.01）.Hypoxia could not affect the transcription of HIF-1α（F=1.995,P＆gt;0.05）.However,the expressions of mRNA and protein of HIF-1α were upregulated under hypoxia in a time-dependent manner,which could also be observed in DEC1 and protein levels（F=18.950,92.567,15.775,P＆lt;0.01）.The expression of HIF-1α protein positively correlated with both mRNA and protein of DEC1 according to Pearson correlation analysis（r=0.885,0.826,P＆lt;0.05）.Conclusion The high expression of DEC1 was observed in hepatocellular carcinoma cell lines.Hypoxia may induce the over-expression of DEC1.