Objective: To screen novel genes related to adriamycin (Adr) resistance from human ovarian cancer resistance cell line OC3/Adr. Methods: Multidrug resistant ovarian cancer cell line OC3/Adr was induced by intermittent treatment of the human parent cell line OC3 with high concentration Adr. The difference of gene expression was screened by using different display analysis to the acquired Adr-resistance subline OC3/Adr and its parent cell line OC3. Results: OC3/Adr cell line was obtained which was more resistance to Adr than the parent cell line OC3 with the resistance index (RI) of 15.4. The OC3/Adr cell line also showed cross-resistance to other anti-cancer drugs (VP16, CDDP,5FU ). It grew slowly and exhibited changes of cell cycle. A number of differentially expressed ESTs (Expressed Sequence Tags, ESTs) were identified at mRNA level between the OC3/Adr and OC3. Four of 18 different ESTs were sequenced. The 431/432 base pair S1 was homologous to human sperm zona pellucida binding protein, while the other two ESTs, S3 and S4, were new gene segments, which were registered to GenBank with the number of AF 117656 and AF 126507 respectively. Particularly, the expression of S2 sequence increased in all the drug-resistance cell lines and S3 sequence overexpressed in human ovarian cancer tissues as compared with benign ovarian tumors. Adr in ovarian cancer OC3/Adr is involved with changes of multiple gene expressions.

单细胞凝胶电泳在检测人精子DNA损伤中的应用

单细胞凝胶电泳(single cell gel electrophoresis,SCGE)又称彗星实验,是一种在单细胞水平上检测真核细胞DNA损伤与修复的方法.由于SCGE快速、简便和灵敏,已广泛用于检测外来化学物质对体细胞DNA的损伤[1].目前,这项技术广泛应用于检测人的肿瘤细胞[2]、淋巴细胞[3]、成纤维细胞[4]等,对动物的检测则有肝细胞、血细胞[5]等,以及植物细胞[6]DNA的损伤.精子DNA是精子细胞内重要的成分,是遗传物质的直接载体.临床资料显示,精子DNA损伤与男性不育有直接的关系,精子DNA的损伤关系到子代和亲代两代的健康[7,8].然而,由于精子细胞核特有的致密结构,DNA很难与核蛋白分离,使SCGE用于检测人精子DNA损伤有一定的局限.国内学者徐德祥[9]用改进的SCGE技术,成功地在显微镜下观察到人精子细胞DNA链的断裂,使近几年SCGE技术在评估男性生殖中得到了广泛的应用和迅速的发展.全文主要就SCGE的原理、具体操作方法及其在检测人精子DNA损伤中的应用和一些注意事项作一介绍.