Nucleostemin在结直肠癌和正常结直肠组织中的表达及其意义

摘要

背景:Nucleostemin(NS)是一个与细胞增殖相关的核蛋白,部分研究显示其仅高表达于干细胞和肿瘤细胞.成体组织分化细胞中未见NS表达.目的:探讨NS在结直肠癌和正常结直肠组织中的表达及其意义.方法:收集38例结直肠癌患者的癌组织及其相应癌旁正常组织标本,以实时RT-PCR和蛋白质印迹法检测NS mRNA和蛋白表达.结果:实时PCR扩增曲线显示结直肠癌组织和正常结直肠组织均有NS基因指数式扩增,癌组织NS mRNA表达量显著高于正常组织(1.8939±0.9529对1,P=0.011).蛋白质印迹法证实NS蛋白在正常组织中表达较微弱或几乎无表达,癌组织中其表达显著增高(1.5397±0.3625对0.6336±0.3443,P=0.001).结论:结直肠癌组织和正常结直肠组织中均存在NS基因,推测其微量表达可调节细胞正常增殖,而异常高表达则可通过某些机制促进细胞恶性增殖.%Some studies revealed that nucleostemin (NS), a cell proliferation-related protein, was highly and exclusively expressed in the nucleus of stem cells and tumor cells, and was not expressed in differentiated cells of adult tissue. Aims: To investigate the expression and significance of NS in cancerous and normal colorectal tissues. Methods: Cancerous and adjacent normal tissues of 38 colorectal carcinoma patients were collected. Real-time RT-PCR and Western blotting were used to detect the expressions of NS mRNA and protein. Results: The amplification curve of real-time PCR illustrated exponential amplification of NS gene in both cancerous and normal colorectal tissues, the expression level of NS mRNA in cancerous tissue was significantly higher than that in normal tissue (1.8939±0.9529 vs. 1, P=0.011). Western blotting confirmed that NS protein was highly expressed in cancerous tissue while was weakly expressed or almost absent in normal tissue (1.5397±0.3625 vs. 0.6336±0.3443, P=0.001). Conclusions: NS gene exists in both cancerous and normal colorectal tissues. It is postulated that minute amount of NS can regulate the proliferation of normal cells, whereas aberrant overexpression of NS can promote malignant proliferation of tumor cells through some specific mechanisms.