Earlier studies discovered that extracellular miRNAs circulated in the bloodstream and the circulating miRNAs were remarkably stable. Detection of elevated levels of tumor associated miRNAs in serum of patients with diffuse large B-cell lymphoma [32] leads to widely investigation of circulating miRNAs in many human cancers, including breast cancer [33],

lung cancer [34], prostate cancer [35], and renal cell carcinoma [36] and so on. The expression profile of miRNAs in serum/plasma of the patients with bladder cancer was also investigated and some important circulating miRNAs in bladder cancer had been identified [37,38]. These studies support the use of serum/plasma miRNAs as noninvasive means of bladder cancer detection. Serum miR-19a expression has been reported STA-9090 manufacturer this website to correlate with worse prognosis of patients with non-small cell lung cancer [39]. We detected the level of miR-19a in plasma of patients with bladder cancer and found that miR-19a was also increased which was p38 MAPK phosphorylation consistent with its high level in the cancer tissues. The up-regulation of miR-19a in the plasma might origin from the tumor cells which needs to be improved further. MiRNAs can be detected easily in small amount samples and are stable against degradation and can be detectable

in bodily fluids including serum, plasma, saliva, urine and tears [40,41]. The innate properties of miRNAs make them attractive as potential biomarkers. So miR-19a can be developed as a new diagnostic marker for bladder cancer detection. Further analysis of the correlation of miR-19a expression level with clinical outcome will offer important information about the O-methylated flavonoid relationship of miR-19a levels with

the clinical diagnosis, therapy and outcome, which will be useful for individualized therapies. In consideration of the possible secretion of miR-19a from the tumor cells to the plasma, the level of miR-19a in urine samples of the patients will be examined. Voided urine can be noninvasively obtained, be designed not only for diagnosis, but also for monitoring disease recurrence and response to therapy [42,43]. So development of miR-19a as a novel urinary biomarker for bladder cancer will be urgently required for early detection of cancer and individualized therapies. Conclusion In summary, we determined the high expression of miR-19a in the cancer tissues and plasma of patients with bladder cancer and also indicated the oncogenic roles of miR19a in bladder cancer which was dependent on targeting PTEN. Our data provided the potential diagnostic and therapeutic roles of miR-19a in bladder cancer firstly. Acknowledgements This work was supported by grants from the Scientific Research Foundation of Sichuan Provincial Health Department (No.140493). References 1. Knowles MA: Molecular pathogenesis of bladder cancer. Int J Clin Oncol 2008, 13:287–297.PubMedCrossRef 2.