Decreased expression of long noncoding RNA NBAT1 indicates a poor prognosis and promotes cell proliferation and EMT in bladder cancer

Objective: Dysregulation of long non-coding RNAs (lncRNAs) may exert critical roles in tumor progression in human. In the current research, we focused on lncRNA NBAT1 and explored its expression pattern and biological function in bladder cancer (BCa). Methods: NBAT1 expression in 79 BCa tissues was assessed through quantitative Real-time PCR (qRT-PCR) and its correlation with clinicopathological features and prognosis was later analyzed. Moreover, in vitro assays, including MTT assay, transwell migration and invasion assays, Annexin V-binding assay and Cleaved Caspase-3 ELISA assay were performed to measure the effect of NBAT1 overexpression in BCa cell lines. Protein levels of epithelial-mesenchymal transition (EMT) markers were determined by western blot. Results: NBAT1 expression was remarkably decreased in BCa tissues and cell lines, and NBAT1 levels were closely associated with tumor grade, tumor stage, and unfavorable overall survival. Besides, the results of in vitro experiments demonstrated that up-regulation of NBAT1 significantly inhibited BCa cell proliferation, migration, invasion, and promoted cell apoptosis. Overexpression of NBAT1 was observed to suppress EMT through the regulation of E-cadherin and N-cadherin expression. Conclusion: Our present study suggested that lncRNA NBAT1 might be a novel molecule involved in BCa progression, which provide a potential diagnostics or predictive biomarker and therapeutic approach.