Circulating miR-205: a promising biomarker for the detection and prognosis evaluation of bladder cancer

MicroRNA (miRNA) expression profile analysis indicated that miR-205 was upregulated in bladder cancer tissue compared to healthy tissue. The aim of this study is to analyze value of circulating miR-205 for the detection and prognosis evaluation of bladder cancer (BC). Eighty-nine patients with BC and 56 healthy controls (HC) were enrolled in the study. miR-205 expression was determined using TaqMan quantitative real-time polymerase chain reaction assay and further correlated with patients’ clinicopathological parameters and follow-up data. The results indicated that plasma miR-205 was upregulated in BC compared with HC (P < 0.001) and in muscle invasive BC (MIBC) compared to nonmuscle invasive BC (NMIBC) (P = 0.016). miR-205 yielded an area under the receiver-operating characteristic curve of 0.950 with 76.4 % sensitivity and 96.4 % specificity in discriminating BC from HC, and 0.668 with 57.1 % sensitivity and 77.0 % specificity in distinguishing MIBC from NMIBC. Plasma miR-205 expression was significantly associated with tumor stage (P < 0.001) and pathological grade (P = 0.048). The results indicated that BC patients with high miR-205 expression experienced shorter disease-free survival and disease-specific survival (P = 0.022 and P = 0.026; P = 0.027 and P = 0.034; respectively), which was not proven by multivariate Cox regression analysis (multi-Cox) (P = 0.0765 and P = 0.279, respectively). Log-rank test showed that NMIBC patients with high miR-205 expression experienced shorter cancer-free survival (P = 0.044). Log-rank test and univariate and multivariate Cox regression analyses did not indicate that high miR-205 expression in NMIBC patients was associated with cancer-specific survival (P = 0.079, P = 0.089, and P = 0.201, respectively). In conclusion, miR-205 may be a promising biomarker for the detection and prognosis evaluation of BC.