The increased expression of miR-19a in the plasma of bladder cancer patients suggested that miR-19a can be developed as a potential diagnostic marker #Salubrinal supplier randurls[1|1|,|CHEM1|]# which can be combined with other miRNAs’ expression to detect bladder cancer. Figure 5 Expression of miR-19a in the plasma of patients with bladder cancer. (A) Normalized expression of miR-19a in the plasma of 50 patients with bladder cancer and 50 healthy individuals. (B) Correlation of miR-19a expression in the plasma with the tumor grades of bladder cancer. Discussion The up-regulated
expression of miR-17–92 cluster has been reported in a variety of cancers including multiple myeloma, leukemia, colorectal cancer and breast cancer [22–24]. The miRNA cluster produces a single primary transcript yielding the six mature miRNAs: miR-17, miR-18a, miR-19a, miR-20a, miR-19b, and miR-92a. miR-19 has been identified GSK1904529A mouse as the key member responsible for the oncogenic activity [25,26]. However, the role of miR-19 in bladder cancer remains unknown. In this study, we investigated the expression of miR-19a in a great deal of patients with bladder cancer and dissected the roles and mechanisms of miR-19a in bladder cancer carcinogenesis. We found that miR-19a was significantly up-regulated in bladder cancer tissues and the high
expression of miR-19a was associated with the more aggressive phenotypes of bladder cancer. Gain or loss of function of miR-19a in bladder cancer cells also indicated that miR-19a can promote cell growth which click here was consistent with its role in other cancer types. The important role of miR-19a in regulating bladder cancer cell invasion, migration and in vivo carcinogenesis needs to be further confirmed. In case anti-miRs of miR-19a can suppress tumor growth in vivo significantly, miR-19a can be further developed as new target for bladder cancer therapy as
miRNAs has advantages of being small and easy to delivery, safer than other gene therapy methods [27,28]. To further dissect the mechanism by which miR-19a functioned as an oncogenic miRNA in bladder cancer, we analyzed the relationship of miR-19a and PTEN in bladder cancer and found that the regulatory role of miR-19a in bladder cancer cells was dependent on targeting PTEN. PTEN is identified as a tumor suppressor that is mutated in a large number of cancers at high frequency. It negatively regulates intracellular levels of phosphatidylinositol-3,4,5-trisphosphate in cells and functions as a tumor suppressor by negatively regulating AKT/PKB signaling pathway [29–31]. AKT/PKB signaling pathways answer to growth factors and other extracellular stimuli to regulate several cellular functions including nutrient metabolism, cell growth, apoptosis and survival. miR-19a may repress the expression of PTEN which further lead to the unlimited cell proliferation of bladder cancer cells.