title: Expression of miR-136 is associated with the primary cisplatin resistance of human epithelial ovarian cancer.
abstract: MicroRNAs (miRNAs) are involved in regulating the response of cancer cells to various therapeutic interventions, yet their involvement in the chemoresistance of human epithelial ovarian cancer is not fully understood. We found that miR-136 was significantly downregulated in specimens from patients with chemoresistant epithelial ovarian cancer. In the present study, we aimed to clarify the role of miR-136 in regulating the chemoresistance of ovarian cancer. Thirty-four tumor bank specimens and 2 well-established human ovarian cancer cell lines, C13 and OV2008, were used. We found that miR-136 expression was significantly reduced in primary platinum-resistant patients and the ovarian cancer OVC cell line. Enforced expression of miR-136 decreased the chemoresistance to cisplatin in OVC cells through inhibition of cell survival. In addition, we found no association between miR-136 and migration or invasion potential in the ovarian cancer cell lines. However, in the platinum-resistant C13 cell line, the overexpression of miR-136 markedly promoted an apoptotic response to cisplatin. Furthermore, the levels of adducts corrected with their extent of DNA damage/repair, in terms of the percentage of DNA in comet tails, tail length, tail moment (TM), and olive tail moment (OTM), revealed that miR-136 is essential for the repair of cisplatin-induced DNA damage. Our findings suggest that miR-136 may function as an anti-oncogene and deficiency of miR-136 expression in ovarian cancer can induce chemoresistance at least in part by downregulating apoptosis and promoting the repair of cisplatin-induced DNA damage. Thus, miR-136 may provide a biomarker for predicting the chemosensitivity to cisplatin in patients with epithelial ovarian cancer.
authors.affiliation: Dalian Medical University, Dalian, Liaoning 116044, P.R. China.
authors.forename: Henan
authors.initials: H
authors.lastname: Zhao
authors.affiliation: Dalian Medical University, Dalian, Liaoning 116044, P.R. China.
authors.forename: Sha
authors.initials: S
authors.lastname: Liu
authors.affiliation: Dalian Medical University, Dalian, Liaoning 116044, P.R. China.
authors.forename: Guang
authors.initials: G
authors.lastname: Wang
authors.affiliation: Dalian Medical University, Dalian, Liaoning 116044, P.R. China.
authors.forename: Xian
authors.initials: X
authors.lastname: Wu
authors.affiliation: Dalian Medical University, Dalian, Liaoning 116044, P.R. China.
authors.forename: Yanfang
authors.initials: Y
authors.lastname: Ding
authors.affiliation: Department of Radiation Oncology, University of Manitoba, Winnipeg, MB R37 2N2, Canada.
authors.forename: Gordon
authors.initials: G
authors.lastname: Guo
authors.affiliation: Obstetrics and Gynecology Hospital, Dalian, Liaoning 116003, P.R. China.
authors.forename: Jiyong
authors.initials: J
authors.lastname: Jiang
authors.affiliation: Dalian Medical University, Dalian, Liaoning 116044, P.R. China.
authors.forename: Shiying
authors.initials: S
authors.lastname: Cui
mesh_terms: D000970:Antineoplastic Agents / Q000008:administration & dosage*; D000077216:Carcinoma, Ovarian Epithelial; D045744:Cell Line, Tumor; D002465:Cell Movement; D002945:Cisplatin / Q000008:administration & dosage*; D004249:DNA Damage / Q000187:drug effects; D004260:DNA Repair; D015536:Down-Regulation; D019008:Drug Resistance, Neoplasm; D005260:Female; D006801:Humans; D035683:MicroRNAs / Q000235:genetics*; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009375:Neoplasms, Glandular and Epithelial / Q000188:drug therapy* / Q000235:genetics; D010051:Ovarian Neoplasms / Q000188:drug therapy* / Q000235:genetics
chemical_list: D000970:Antineoplastic Agents; C577037:MIRN136 microRNA, human; D035683:MicroRNAs; D002945:Cisplatin