Abstract: Objective To study the relationship between the expression of MiR-31 and the efficacy of paclitaxel combined with cisplatin chemotherapy in elderly women with ovarian cancer. Methods Fifty two elderly inpatients with ovarian cancer were treated with paclitaxel combined with cisplatin chemotherapy from 2011 to 2014. The therapeutic effect was followed up for analysis of the expression of MiR-31 in cancer tissues of pre- and post-treatments. Results The 3-year survival rate was 25% （13/52） and the progression-free survival rate was 15.4% （8/52）. The median overall survival time of patients with low expression of MiR-31 before treatment was 12 months, significantly shorter than 28 months in the patients high MiR-31 expression （P<0.05）. Additionally, the median progression-free survival time of patients with low MiR-31 expression was 8 months, much lower than 16 months with high MiR-31 expression （P<0.05）. After treatments, the patients with high expression of MiR-31 （>65%） presented as long as 34 months of median overall survival time when compared with those who had low MiR-31 expression and short survival time （12 months） （P<0.05）. The median progression-free survival time of MiR-31 （>65%） was 24 months, which was significantly longer than 8 months in those with low MiR-31 expresion （P<0.05）. Paclitaxel-cisplatin chemotherapy and MiR-31 expression are independent prognostic factors of ovarian cancer. Conclusions The level of MiR-31 expression is helpful for assessment of the treatment efficacy and prognosis of elderly women with ovarian cancer.

Key words: MicroRNA-31, Ovarian cancer, Paclitaxel and cisplatin, Prognosis, Elderly women