结肠癌组织中差异表达基因的筛选和鉴定

目的 筛选和克隆结肠癌和正常结肠组织差异表达的基因片段，为探讨结肠癌的发病机制提供线索。方法 应用基因差异显示技术（DD—PCR），比较结肠癌和正常结肠组织基因表达的差异，对其中一条有明显差异的基因片段进行克隆、测序，测序结果提交GenBank数据库中进行同源性分析，并用半定量RT—PCR进行初步鉴定。结果 同源性分析表明，该片段与已知基因DDX32高度同源（99％）。RT—PCR结果显示，在结肠癌组织中该基因mRNA的表达水平显著高于正常结肠组织（P〈0．05）。结论 DD—PCR是筛选差异表达基因的有效手段；在结肠癌组织中DDX32基因的表达显著高于正常结肠组织，此结果为研究DDX32基因在结肠癌发病中的作用提供了线索。

Screening and identification of differentially expressed genes in colorectal carcinoma

Objective To screen and identify differentially expressed genes in colorectal carcinoma and explore the possible molecular pathogenesis of colorectal carcinoma.Methods The differentially expressed cDNA bands in colorectal carcinoma specimens and matched adjacent normal tissues were isolated by fluorescent mRNA differential display.Following differential display PCR (DD-PCR),all cDNA fragments were sequenced.By using BLAST software,the sequencing results were compared with Genebank database for homologue analysis.RT-PCR was used to detect the expression of one of the differentially expressed genes in colorectal carcinoma samples were identified by semi-RT-PCR.Results BLAST analysis revealed that the cDNA band was homologous to DDX32 (99%) and its up-regulated expression in colorectal carcinoma tissues was confirmed by RT-PCR (P<0.05).Conclusion Differential Display should be an available method for Screening differentially expressed genes.DDX32 gene expression was much higher in colorectal carcinoma tissues than that in matched adjacent normal tissues.Its up-regulated expression in colorectal carcinoma tissues was probably related to the carcinogenesis of colorectal carcinoma.