Abstract
BACKGROUND: Bladder cancer (BC) is the most common malignancy of the urinary tract in China, and the extent of tumor invasion negatively correlates with prognosis. The mechanism of tumor invasion in BC has been unclear until recent studies revealed the critical role of long noncoding RNAs (lncRNAs) in the proliferation and invasion of tumors. Several lncRNAs have been reported to be associated with pathogenesis in BC, but not specifically. METHODS: We used a microarray to screen the candidate lncRNAs with different expressions in BC. The expression of the lncRNAs in BC tissues or cells was identified by reverse transcription polymerase chain reaction (RT-PCR) or quantitative real-time PCR (qRT-PCR), and their ectopic expressions were measured via transfection experiment. The function of the lncRNAs was investigated by flow cytometry, caspase-3 enzyme linked immunosorbent assay (ELISA), Cell Counting Kit-8 (CCK-8), wound healing, transwell and colony formation experiments in vitro and xenograft experiments in vivo. RESULTS: We identified a novel sense lncRNA, NONHSAT070806, that was downregulated in BC tissues and cells and negatively correlated with level of tumor invasion in patients. Furthermore, overexpression of NONHSAT070806 induced apoptosis of T24 and 5637 cells, inhibited the proliferation, migration and invasion of BC cells, and attenuated the tumorigenesis of BC cells both in vitro and in vivo. CONCLUSIONS: NONHSAT070806 may act as a suppressor of BC and is a potential indicator of the invasiveness of BC.