用抑制性消减杂交方法筛选人肾癌相关基因

目的 应用抑制性消减杂交技术构建人肾癌差异表达基因文库并进行差异表达基因筛选.方法 以肾癌细胞株RLC-310和肾近曲小管细胞株HK-2互为实验组和对照组,提取mRNA,应用抑制性消减杂交技术进行正反两向消减杂交,获得人肾癌细胞差异表达基因文库,结合反向Northern斑点印迹杂交,筛选差异基因克隆,并进行测序分析.结果 正向和反向文库共包含1200多个阳性克隆,经斑点杂交筛选后,对213个差异克隆进行测序并经BLAST分析,得到144个差异表达基因,与肾癌相关的高表达基因67个,低表达基因77个,其中新EST 14个,未知功能基因21个;对测序基因进行聚类分析发现与细胞生长、黏附、凋亡等肿瘤细胞生物学行为相关.结论 该文库质量可靠,所筛选出的差异基因和新的基因为进一步筛选肾癌特异性相关基因,绘制肾癌差异基因表达谱,最终阐明肾癌发生、发展、转移机制提供了实验材料和研究靶点.

Screening of differentially expressed genes in human renal cell carcinoma using suppression subtractive hybridization

OBJECTIVE: To suppress COL1A1 and COL3A1 gene expressions in human skin fibroblasts (HSFs) by means of RNA interference (RNAi). METHODS: SSH was performed in two directions to isolate the differentially expressed genes between human a RCC cell line RLC-310 and a normal renal cell line HK-2 (ATCC). The cDNAs obtained from the final nested PCR were directly inserted into T/A cloning vector to establish a subtractive cDNA library of specifically or highly expressed genes in RCC. Reverse Northern dot blotting was performed to screen the truly differentially expressed genes, and 200 positive genes were randomly selected for sequencing. RESULTS: The two-directional subtractive libraries contained more than 1200 clones, and 213 positive clones were obtained using reverse Northern blotting. Sequence analysis of these clones identified 144 differentially expressed genes, including 67 up-regulated and 77 down-regulated genes, in which 14 novel ESTs and 21 functionally unknown genes were found. Cluster analysis indicated the involvement of the sequenced genes in cell growth, cell adhesion and apoptosis.CONCLUSION: Reliable subtractive cDNA libraries of human RCC have been constructed successfully with SSH. The identification of the gene expression profile in RCC may help clarify the mechanism of tumorigenesis and development of RCC, and also sheds light on new targets for prevention, diagnosis and therapy of this malignancy.