Abstract 2235: Circulating microRNA-205 as a potential prognostic biomarker for recurrent ovarian cancer

Abstract

Abstract Background: Ovarian cancer is the most lethal gynecological malignancy and the fifth most common cancer in women in the U.S. Patients diagnosed in advanced-stage ovarian cancer have 70-95 % chance of relapse. Additional non-invasive approaches to monitor response to treatment and to predict recurrent disease are urgently needed. Aberrant expression levels of circulating microRNAs are diagnostic, prognostic, and predictive biomarkers in ovarian cancer. We recently published that microRNA-205 (miR-205) expression is elevated in ovarian cancer and correlates with advanced-stage disease. Here, we investigate circulating microRNA-205 as a potential biomarker for monitoring disease in patients diagnosed with advanced-stage ovarian cancer. Methods: Plasma samples from normal controls (n=12) and recurrent stage III/IV ovarian cancer patients (n=5) in our biorepository were used. Samples were collected 1 day before surgery operation and at 1 month, 2 months and 6 months after the primary surgery. All samples were from serous ovarian carcinomas. All the patients went through the standard chemotherapy and CA-125 levels were decreased to the normal range (<35U/ml) at 6 months after the surgery. All recurrent disease was detected within 2 years after primary surgery. Circulating microRNAs were extracted from plasma of ovarian cancer patients and normal controls using miRNeasy Mini Kit (Qiagen). The reverse transcriptions were conducted using qScrip microRNA cDNA Synthesis Kit. (VWR). The circulating miR-205 expression was confirmed by quantitative real-time polymerase chain reaction (qPCR). Results are reported as mean ± S.E. Student’s t-test was applied. Results: Our results confirmed that the expression of circulating miR-205 was significantly elevated in stage III/IV ovarian cancer plasma samples compared with normal controls (5.91 fold; p<0.05). Compared with levels in paired pre-operative plasma, circulating miR-205 expression was significantly lower in the post-operative plasma at 1 month (p<0.01), gradually rose to pre-operative levels at 2 months, and significantly increased by 6 months post-operation (p <0.05). Circulating miR-205 expression levels were significantly increased at 6 months in post-operative samples when CA-125 levels were at normal range, suggested the circulating miR-205 can potentially be used as a biomarker for ovarian cancer recurrence. Conclusion: Dynamic changes of the circulating miR-205 expression in pre- and post-operative plasma samples of recurrent stage III/IV ovarian cancer patients demonstrated that circulating miR-205 levels could be used as non-invasive biomarkers for monitoring disease in patients diagnosed with advanced stage ovarian cancer. Further investigation is warranted in larger cohorts of patients. Citation Format: Meghan W. Kusch, Julia A. Chapman, Carl P. Weiner, Katherine F. Roby, Dineo Khabele, Helen H. Zhou. Circulating microRNA-205 as a potential prognostic biomarker for recurrent ovarian cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 2235.