OBJECTIVETo identify potential miRNA involved in epithelial ovarian cancer (EOC) invasion and metastasis.

METHODSmiRNA microarray was applied to compare the miRNA expression profile between SKOV-3ip and SKOV-3 cells. Bioinformatics programs (TargetScan, MicroCosm, PicTar and GO) were used to analyze the miRNA and their potential target genes. Real-time RT-PCR was used to confirm the results of microarray and for expanding detection in another paired EOC cell lines (HO-8910 and HO-8910PM).

RESULTSTotally, expressions of 42 miRNA were found significantly different between SKOV-3ip and SKOV-3 cells. Among them, 10 miRNA were down-regulated, including let-7a, let-7f, miR-22 and miR-886-5p; while 32 were up-regulated, for example, let-7e and miR-519e. Bioinformatic analysis indicated that let-7a, let-7e, let-7f, miR-22 and miR-886-5p may be involved in cancer invasion and metastasis. Meanwhile, real-time RT-PCR confirmation and statistic analysis showed that let-7f and miR-22 expressions were significantly different between ovarian cancer cell lines with various invasive and metastatic capacity (P < 0.05).

CONCLUSIONThe expression of let-7f and miR-22 is low in ovarian cancer cells with high invasive and metastatic capacity. It suggests that they are potential tumor suppressor genes. Further research on their role and mechanism is needed.

Cell Line, Tumor ; Cystadenocarcinoma, Serous ; genetics ; metabolism ; pathology ; Female ; Gene Expression Profiling ; Humans ; MicroRNAs ; genetics ; metabolism ; Microarray Analysis ; methods ; Neoplasm Invasiveness ; Neoplasm Metastasis ; Ovarian Neoplasms ; genetics ; metabolism ; pathology