Molecular identification of miR-145 and miR-9 expression level as prognostic biomarkers for early-stage cervical cancer detection

Background: MicroRNAs (miRNAs) may act as carcinogen or tumor suppressor genes by targeting various biological molecules. Therefore, it is important to identify significant markers for prognosis, diagnosis treatment strategies of cancers. Objective: To evaluate the clinical importance and prognostic value of miR-9 and miR-145 in cervical cancer. Method: miRNAs expression was detected using quantitative real-time polymerase chain reaction in cervical cancer specimens and adjacent normal tissues. Results: MiR-9 up-regulated in cervical cancer specimens than adjacent normal tissues (9.743 +/- 2.172 vs. 2.131 +/- 1.083; P < 0.05). MiR-145 was decreased in cervical cancer specimens compared to corresponding normal tissues (2.189 +/- 0.724 vs. 7.173 +/- 1.558 P < 0.05). In addition, increased expression of miR-9 was strongly linked to lymph node metastasis (P = 0.017) and vascular invasion (P = 0.011). On the other hand, the low expression of miR-145 was related to advanced FIGO stage (P = 0.007), lymph node metastasis (P = 0.02) and vascular invasion (0.026). Kaplan-Meier survival and log-rank analysis suggested that patients with high expression of miR-9 had shorter overall survival compared with those with low expression (log-rank test P = 0.028; P < 0.001). In addition, shorter overall survival time was remarkably linked to decreased expression of miR-145 (log-rank test P < 0.001). Multivariate Cox proportional hazards model analysis of miR-9 and miR-145 showed that FIGO stage (P = 0.011) high expression of miR-9 and low expression of miR-145 (P = 0.023; P = 0.031) were independent prognostic factors for overall survival of patients. Conclusions: miRNA-145 and 9 may be as potential prognostic marker in patients suffering from cervical cancer.