Expression and clinical significance of microRNA-7 in serum of ovarian cancer patients

Abstract

Objective To explore the expression and clinical significance of microRNA-7 (miR-7) in serum of ovarian cancer patients. Methods Serum samples of 42 ovarian patients confirmed by pathological histology and 40 healthy women who underwent a physical exam were collected from January 2011 to January 2012 in the Sixth People′s Hospital of Foshan Nanhai District of Guangdong Province. Expression levels of miR-7 in the serum samples of the two groups were examined using reverse transcription-real time polymerase chain reaction (RT-PCR). The relationship between the expression of miR-7 and the clinicopathologic feature of ovarian was analyzed. Results Compared with the controls, the expression of miR-7 in the serum of ovarian cancer patients was significantly reduced (0.246±0.017 vs. 0.488±0.042), with a significant difference (t=11.23, P=0.01). The expression of miR-7 in the serum of ovarian cancer patients was related to the clinical stage (t=10.12, P=0.01), pathological type (t=6.90, P=0.02), differentiation degree (t=4.46, P=0.03), regional lymph node or distant metastasis (t=5.62, P=0.02), but it was not related to the age (t=0.03, P=0.83). The patients with high miR-7 expression had better overall survival than the patients with low miR-7 expression (36.7 months vs. 24.3 months), with a significant difference (χ2=6.04, P=0.02). Conclusion The expression of miR-7 in serum of ovarian cancer patients is down regulated, which may be helpful for the overall assessment of ovarian carcinoma. miR-7 may be one of the important prognostic indicators for ovarian carcinoma. Key words: Ovarian neoplasms; MicroRNAs; Reverse transcriptase polymerase chain reaction