从卵巢癌cDNA文库中筛选新的肿瘤标志物

采用SEREX法筛选了自行构建的中国人卵巢癌cDNA表达文库 ,得到 2 7个阳性克隆 ,其中 3个为全长cDNA。序列分析和同源性比对结果表明所获得的 2 7个克隆分属于分化抗原、细胞结构蛋白及功能未知三类。选择其中一个全长cDNAMY OVA 13(该基因编码的蛋白是MAD2 ) ,利用基因工程方法克隆、表达和纯化得到目的蛋白 ,采用点杂交方法检测了MY OVA 13目的蛋白与正常人和肿瘤患者中的血清学反应。MY OVA 13抗体只在肿瘤组中检测到 (5 / 74 ) ,在正常组中均为阴性 ;间接ELISA测定结果显示 ,MY OVA 13抗体的水平在肿瘤组中均高于正常组 ,其中肝癌和前列腺癌组与正常组相比 ,在统计学上有显著差异 ,P值分别 <0 0 1和 <0 0 5。我们的初步结果表明MY OVA 13及其抗体具有一定的肿瘤特异性 ,有可能作为肿瘤诊断的标志物

Screening New Tumor Markers from cDNA Expression Library of Ovarian Cancer

In order to search for new candidate tumor markers,we have utilized the method of SEREX to screen a cDNA library of an ovarian cancer cell constructed by ourselves with autologous serum In this way,we have identified 24 distinct gene clones (MY-OVA-1 to MY-OVA-27) Sequence analysis has showed that all gene clones could be classified to 3 catagories:those encoding differential antigens,those encoding structure proteins and those with unknown properties Then we evaluated the immunogenicity of MY-OVA-13 antigen using bacterially synthesized and purified proteins Serological analysis with dot-blot showed that auto-antibodies against MY-OVA-13 was only detected in tumor patients (5/74) and not detected in normal subjects (0/13) To determine the levels of these autoantibodies in sera,we further examined the sera of 84 tumor patients and 36 normal subjects with ELISA method Judged by a cut-off value of 0 620 A 490 ,none of normal subjects were positive with anti-MY-OVA-13 au to-antibody,whereas 11 patients (11/84) reached positive level for the antibody reaction Our findings indicated that the autoant ibody against MY-OVA-13 displayed some tumor-specificity If our results are confirmed by further studies,it could be potential for clinical use as a tumor marker -