miRNA expression pattern associated with prognosis in elderly patients with advanced OPSC and OCC.

The long-term survival for elderly patients with advanced ovarian papillary serous carcinoma (OPSC) does not exceed 30%, and the incidence and prognosis rise continuously after menopause. The aim of this study was to identify the differences in key miRNAs and their potential regulators through miRNA microarray analysis, functional target prediction, and clinical outcome between the elderly patients with advanced OPSC and ovarian clear cell carcinoma (OCC) who all suffered poor prognosis, to identify the pathogenetic basis, and to improve the understanding of the molecular basis of advanced OPCS in elderly patients. Through microarray analysis, we found 52 unique miRNAs with significant fold‑change in expression levels, of which 9 were upregulated, whereas 43 were downregulated in OCC patients compared to elderly OPSC patients with advanced stage. Among these prediction miRNAs, miR-30a, miR-30e and miR-505 were found to have some common cancer-related targets. Lower expression of these three miRNAs of advanced OPSC in elderly patients, all associated with significantly poorer survival rate, strongly suggesting that they could be critical oncogenes and take important roles in OPSC etiology in elderly patients with advantaged stage. Functional analyses support the above hypothesis. Their targets, ATF3, STMN1 and MYC suggest that OPSC also has aggressive biological behavior when presented with advanced stage, and support the epidemiology results that incidence and mortality of advanced OPSC increases continuously. miR-30a, miR-30e and miR-505 may be important pathogenetic factors for OPSC in elderly patients with advanced stage. Age could be regarded as a continuous covariate in this process. This may improve the understanding of molecular underpinnings of advanced OPSC in elderly patients, and provide improved diagnostic, prognostic and therapeutic approaches.