LncRNA PTAR activates the progression of bladder cancer by modulating miR-299-3p/CD164 axis

Bladder cancer (BC) occurs in the urinary system which has high incidence and mortality. During past decades, lots of long noncoding RNAs (lncRNAs) have been identified to function in cancer progression, including BC. In our research, we targeted at investigating the functions and mechanisms of lncRNA pro-transition associated RNA (PTAR) in BC. Functional assays were implemented to access the changes of BC cell phenotype. Mechanistic assays were applied for confirming the interaction between RNAs. Based on the collected data, PTAR expression was high in BC cells and silenced PTAR repressed BC cell proliferative, migratory and invasive abilities but improved cell apoptotic ability. In vivo study also verified PTAR depletion inhibited BC tumor growth. Furthermore, miR-299-3p was confirmed to bind with PTAR and its overexpression suppressed malignant behaviors of BC cells. Cluster of differentiation 164 (CD164) was proved to be miR-299-3p target. Rescue experiments implied overexpressed CD164 offset the inhibitory function of PTAR depletion on BC cell phenotype. Additionally, CD164 was uncovered to combine with C-X-C motif chemokine receptor 4 (CXCR4) to switch on PI3K/AKT pathway. To conclude, PTAR facilitates BC development via regulating miR-299-3p/CD164 axis and activating PI3K/AKT pathway.