结直肠癌中缺氧诱导因子-1α与Survivin表达的关系

Hypoxia inducible factor 1α expression in colorectal cancer and its correlation with Survivin

目的探讨结肠癌LSl74T细胞及结直肠腺癌组织中缺氧诱导因子-1α（HIF-1α）的表达及与Survivin的关系。方法构建靶向HIF-1α的质粒pSilence-2．1-U6-siRNA并鉴定，采用阳离子脂质体转染法将其转染LS174T细胞，低氧培养24h，应用逆转录-聚合酶链反应（RT—PCR）、West。eTnblot检测siRNA对HIF-1α的抑制作用。WesternMot检测Survivin蛋白表达。应用免疫组织化学方法检测69例人结直肠腺癌组织中HIF-1α、Survivin蛋白的表达。结果LSl74T细胞转染靶向HIF-1α的siRNA表达载体后，HIF-1α、Survivin表达显著下降。69例结直肠腺癌组织中，HIF-1α、Survivin蛋白的阳性表达率为66．7％（46／69）和56．5％（39／69）。腺癌组HIF-1α蛋白阳性表达率显著高于腺瘤组（P〈0．01）。Ⅲ期腺癌HIF-1α蛋白表达显著高于Ⅰ～Ⅱ患者（P〈0．05）。结直肠腺癌中HIF-1α表达与Survivin显著正相关。结论结直肠腺癌发展过程中HIF-1α与Survivin表达密切相关。

Objective To investigate the correlation between the expression levels of hypoxia inducible factor-1α （HIF-1α） and Survivin in human the colorectal carcinomas （CRCs）. Methods Plasmid expressing small interfering RNA （siRNA） targeting HIF-1α mRNA （pSilence-2. 1-U6-siRNA） was constructed and transfected into LS174T cells by Lipofectamine methods. The effect of YIIF-1α on the expression of survivin by siRNA targeting HIF-1α mRNA was studied. The expression of survivin and HIF-1α was detected by reverse transcription-polymerase chain reaction （RT-PCR） and Western blotting. The expres sion of HIF-1α and Survivin was investigated by immunohistochemistry in 69 patients with CRCs. Results The successful construction of pSilence-2. 1-U6-siRNA plasmid was confirmed by sequencing analysis. HIF-1α and Survivin expression levels were markedly down-regulated after the siRNA expression vector targeting HIF--1α was transfected into the LS174T cells. The positive rate of HIF-1α protein in CRCs was significantly higher than that in colorectal adenoma lesions （ P 〈 0.05 ）. There was significant difference in the expression of HIF-1α protein between stage III and stage Ⅰ-Ⅱ CRCs （P 〈0. 01）. The level of HIF-1α was positively correlated with that of Survivin protein （ P 〈 0. 05 ） during colorectal tumor progression. Conclusion There is a positive correlation between the expression levels of HIF-1α and Survivin in tumor progression of human CRCs.