论文部分内容阅读
目的:探讨在体内外环境下缺氧诱导因子1α(HIF-1α)过表达对前列腺癌细胞发生上皮间质转化(EMT)并导致肿瘤侵袭能力升高的影响。方法:对已构建的稳定表达HIF-1α的人前列腺癌LNCaP细胞(LN-CaP/HIF-1α)复苏后培养,对HIF-1α过表达进行鉴定。MTT法测定细胞增殖;检测转染前后培养液上清PSA水平;软琼脂成瘤实验比较两种细胞体外成瘤能力;将转染前后的LNCaP细胞注射免疫裸鼠皮下建立皮下肿瘤模型,观察肿瘤生长情况;收集肿瘤标本进一步行免疫组化处理。结果:免疫荧光和Western印迹证实LNCaP/HIF-1α细胞中HIF-1α过表达。同LNCaP细胞相比,转染HIF-1α的人前列腺癌LNCaP细胞培养液中PSA水平明显降低;MTT法显示其更具有增殖活性,体外成瘤能力更强。体内实验显示皮下肿瘤成瘤率提高,成瘤时间提前。肿瘤标本免疫组化提示转染组E钙粘蛋白表达下调,波形蛋白表达上调。结论:HIF-1α过表达能够封闭E钙粘蛋白,上调波形蛋白表达,提示HIF-1α过表达可能通过诱导EMT增强LNCaP细胞侵袭能力。
Objective: To investigate the effect of over-expression of hypoxia-inducible factor-1α (HIF-1α) on epithelial-mesenchymal transition (EMT) in prostate cancer cells induced by in vivo and in vitro environment and the invasion of tumor cells. Methods: The human prostate cancer LNCaP cells (LN-CaP / HIF-1α) stably expressing HIF-1α were revived and the expression of HIF-1α was identified. The cell proliferation was measured by MTT assay. The level of PSA in supernatants was detected before and after transfection. The soft agar assay was used to compare the tumorigenicity of the two cells in vitro. LNCaP cells before and after transfection were injected subcutaneously into nude mice to establish a subcutaneous tumor model. Growth conditions; collection of tumor specimens further line immunohistochemical treatment. Results: Immunofluorescence and Western blot confirmed HIF-1α overexpression in LNCaP / HIF-1α cells. Compared with LNCaP cells, the level of PSA in LNCaP cells transfected with HIF-1α was significantly lower than that of LNCaP cells. The MTT assay showed that it had more proliferative activity and stronger ability of in vitro tumorigenesis. In vivo experiments show that subcutaneous tumor growth rate, tumor formation ahead of schedule. Immunohistochemistry of tumor specimens suggested that E-cadherin expression was down-regulated and vimentin expression was up-regulated in transfection group. Conclusion: Overexpression of HIF-1α can block E-cadherin and up-regulate the expression of vimentin, which suggests that HIF-1α overexpression may enhance the invasiveness of LNCaP cells by inducing EMT.