Downregulation of microRNA-145 is associated with aggressive progression and poor prognosis in human cervical cancer

MicroRNAs (miRNAs) play important roles in the processes of tumor initiation and progression. However, miR-145 expression in cervical cancer has been rarely investigated. The aim of this study was to investigate the clinical significance and prognostic value of miR-145 expression in cervical cancer. MiR-145 expression in 114 pairs of human cervical cancer and adjacent normal tissues was detected by real-time quantitative RT-PCR assay. The results showed that miR-145 expression was significantly downregulated in cervical cancer tissues when compared with corresponding adjacent normal tissues (P < 0.001). It was also significantly lower in the cancerous tissues of patients with advanced International Federation of Gynecology and Obstetrics (FIGO) stage cervical cancer than those with early FIGO stage (P = 0.006). In addition, miR-145 was expressed at significantly lower levels in lymph node metastasis-positive patients than in lymph node metastasis-negative patients (P = 0.037). Moreover, poorly differentiated tumors expressed lower miR-145 than well or moderately differentiated tumors (P = 0.012). Patients with vascular invasion or human papillomavirus (HPV) infection also had lower miR-145 expression levels than those without (P = 0.016 and P = 0.025, respectively). Furthermore, Kaplan-Meier analysis showed that cervical cancer patients with low miR-145 expression had shorter overall survival time than those with high miR-145 expression (P < 0.001). When analyzed with a multivariate Cox regression model, miR-145 was identified as an independent prognostic factor for overall survival. Taken together, our results suggest that downregulation of miR-145 in cervical cancer is associated with aggressive progression and poor prognosis and that miR-145 may serve as a prognostic marker.