ABSTRACT
@#[Abstract] Objective: To observe the expression of long-chain non-coding RNA (lncRNA) TPTEP1 in bladder cancer tissues and cells, and to observe its effect on the proliferation and invasion of bladder cancer cells and its molecular mechanism. Methods: From August 2017 to October 2019, 43 cases of bladder cancer tissues and paracancer tissues from the patients treated by surgery in the Department Urology, People's Hospital of Dongxihu Distric of Wuhan City. Real-time fluorescence quantitative polymerase chain reaction (qPCR) was used to detect the expression of lncRNA TPTEP1 in bladder cancer tissues and bladder cancer cell lines (T24, BIU-87, 5637, J82, UM-UC-3). The bladder cancer cells with the lowest lncRNA TPTEP1 expression were selected as the experimental object, and transfected with the negative control plasmid (the control group) and lncRNA TPTEP1 over-expression plasmid (the experimental group), respectively. The effect of lncRNA TPTEP1 upregulation on cell proliferation and invasion was detected by MTT method and Transwell experiment. Bioinformatics techniques were used to predict the possible target molecules of lncRNA TPTEP1. qPCR and WB were used to detect the expression levels of lncRNA TPTEP1 downstream molecules. Results: Compared with adjacent tissues, the expression of lncRNA TPTEP1 in bladder cancer tissues was down-regulated (P<0.01). Compared with normal bladder epithelial cells, the expression of lncRNA TPTEP1 in bladder cancer cell lines was down-regulated (P<0.05), and its expression in T24 cells was the lowest (P<0.01). Up-regulation of lncRNA TPTEP1 could inhibit the proliferation (P<0.05) and invasion (P<0.01) of T24 cells. Bioinformatics technology showed that lncRNA TPTEP1 could bind with miR-129-5p, and miR-129-5p could bind with EMP3; up-regulating lncRNA TPTEP1 could inhibit the expression of miR-129-5p in T24 cells (P<0.01), and indirectly promote the mRNA and protein expressions of EMP3 (P<0.01) in T24 cells. The expression of MAPK/ERK signaling pathway related proteins such as p-MEK, p-ERK1/2, p-AKT and p-PI3K decreased (P<0.01). Conclusion: Up-regulating the low-expressed lncRNA TPTEP1 in bladder cancer cell lines can inhibit the proliferation and invasion of bladder cancer T24 cells, and its mechanism is related to indirect promotion of EMP3 gene expression by down-regulating the expression of miR-129-5p.