卵巢癌相关抗原cDNA表达文库的筛选

SCREENING AND IDENTIFYING OF THE ASSOCIATED ANTIGENS OF EPITHELIAL OVARIAN CANCER

目的:从卵巢癌腹腔积液肿瘤细胞cDNA表达文库中筛选卵巢癌相关抗原。方法:采用SEREX方法从卵巢癌腹腔积液肿瘤细胞构建的cDNA表达文库中筛选阳性克隆。血清学筛选出的阳性克隆与SSH所得的差异表达基因探针进行杂交,最终得到特异性较高的阳性克隆。对这些克隆进行酶切鉴定、测序分析。结果:经二轮血清学筛选和DotBlot杂交,最终得到55个在血清中有相应IgG和(或)IgM自身抗体的卵巢癌差异表达的候选肿瘤抗原克隆。经核苷酸测序、序列分析和相似性比对,结果表明这55个EST片段代表45个基因,可分为6类:①3个与已知卵巢癌相关基因相似的基因,如BARD1等;②15个与其它肿瘤相关基因相似的基因,如TM4SF1等;③6个在一些特殊组织中表达的基因,如FXR1(fragileX-relatedgene1,脆性X染色体相关基因1)等;④8个与一些特殊功能蛋白基因相似的基因,如TIZ;⑤5个与胚胎来源的基因相似的基因,如PKHD1等;⑥8个在GenBank中无相似序列的新基因,如OV-189等。结论:SEREX方法与SSH方法相结合筛选肿瘤抗原的技术路线是一种行之有效的、能筛选具有较高特异性肿瘤抗原的策略。本研究为进一步研究这些抗原在卵巢癌的发生、发展及诊断方面的应用奠定了基础。

Objective：The goal of the study was to screen and identify epithelial ovarian cancer associated antigens from epithelial ovarian cancer cDNA expression library. Methods： A strategy of eombined SEREX（serological identification of antigen by recombinant eDNA expression libraries, SEREX） and SSH（suppression subtractive hybridization,SSH） was used for screening cDNA library. All of the positive clones were sequenced and bioinformatively analyzed with BLAST software in GenBank. Result： 55 positive clones were identified after two cycles detection of seroimmunoscreening and Dot Blot hybridization with probes derived from SSH. It showed that these 55 clones derived from 45 distinct genes and these genes could be grouped into six classes as following according to homology with known EST.（1）Known ovarian carcinoma related genes. BARDI,et al. （2）Homologous genes with other tumors：TM4SFl,et al. （3） Homologous genes with special tissues. FXRI,et al. （4） Homologous genes with special functional： TIZ,et al. （5） Embryo originating genes：PKHDl,et al. （6） Novel genes.. OV-189, et al. Conclusion：It showed that the strategy of combined SEREX and SSH was a potent tool to identify tumor-associated antigens. The association of these antigens with epithelial ovarian cancer and the role that they played in the pathogenesis, development and diagnoses of epithelial ovarian cancer should be further studied.