Down-regulated microRNA-101 in bladder transitional cell carcinoma is associated with poor prognosis

Down-regulation of microRNA-101 (miR-101) expression has been linked to bladder transitional cell carcinoma (BTCC) development. However, the relationship between the expression of miR-101 in BTCC and a patient's prognosis has not yet been studied. Thus, we attempted to explore the correlation of miR-101 and clinicopathological factors of BTCC patients, and evaluate the impact of miR-101 on prognosis of BTCC.

In 88 samples of BTCC (n=72) and normal tissues (n=16), the expressions of miR-101 were detected by quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR). The relationship of miR-101 and clinicopathological factors in BTCC was analyzed statistically. Survival analysis was performed to assess the prognostic significance of miR-101.

Down-regulation of miR-101 was found in BTCC tissues, compared with normal tissues (P<0.05). MiR-101 expression was significantly associated with tumor diameter, tumor stage, tumor grade, lymph node involvement, and lymph node metastasis (all P<0.05). Low-level expression of miR-101 was significantly correlated with shortened survival time (P<0.01). Multivariate Cox regression analysis revealed this significant prognostic impact was independent of other clinicopathologic factors (P<0.01).

Our results suggest that the expression of miR-101 is down-regulated in BTCC, which consequently favored tumor progression. MiR-101 may play an important role as a diagnostic and prognostic marker in BTCC.