Upregulation of miR-3658 in bladder cancer and tumor progression

Despite increasing advances in surgical techniques and adjuvant chemotherapies, bladder cancer remains the ninth leading cause of male malignancy-associated deaths worldwide. Several microRNAs (miRNAs) have been identified to be closely associated with the progression and prognosis of, and response to treatments in various human cancers. However, few studies have investigated the role of miR-3658 in bladder cancer. In this study, we examined the expression of miR-3658 in 96 pairs of bladder cancer tissues and adjacent non-tumor tissues via quantitative reverse-transcription polymerase chain reaction. Results showed that expression of miR-3658 was up-regulated in the bladder cancer tissues as compared with that in the corresponding control tissues (4.15 ± 2.78 vs 2.17 ± 1.14; P < 0.0001). Furthermore, higher miR-3658 expression was significantly associated with lymph node invasion, distant metastasis, histological grade, TNM stage, and tumor recurrence in bladder cancer (all P < 0.0001). miR-3658 expression was not associated with other clinicopathological variables such as age, gender, tumor size, and number (all P > 0.05). Our study revealed that miR-3658 overexpression is involved in tumor progression of bladder cancer, indicating that the miRNA possesses prognostic values.