Knockdown of long noncoding RNA FGFR3- AS1 induces cell proliferation inhibition, apoptosis and motility reduction in bladder cancer.

OBJECTIVES: To study the expression pattern of long non-coding RNA FGFR3 antisense transcript 1(FGFR3-AS1) and the cell proliferation inhibition, apoptosis, and motility changes induced by silencing FGFR3-AS1 in bladder cancer. METHODS: The differential expression levels of FGFR3-AS1 and FGFR3 in tumor tissues and paired normal tissues were determined using Real-Time qPCR in a total of 36 patients diagnosed with bladder cancer (urothelial carcinoma). Pearson's coefficient correlation was used for expression correlation assay. Expression differences of FGFR3-AS1 were analyzed according to grading and staging. FGFR3 protein was detected by western blot assay. Human bladder cancer T24 and 5637 cell lines were transiently transfected with FGFR3-AS1-specific siRNA or negative control siRNA. The cell proliferation changes of transfected bladder cancer cells were determined using CCK-8 assay. Apoptosis caused by knockdown of FGFR3-AS1 was evaluated using ELISA assay. Motility changes induced by knockdown of FGFR3-AS1 were measured using wound healing assay and transwell assay. RESULTS: Both FGFR3-AS1 and FGFR3 were overexpressed in bladder cancer tissues compared to matched normal tissues. They were also positively expressed in bladder cancer. FGFR3-AS1 expression levels were higher in high grade tumors than those in low grade tumors. FGFR3-AS1 expression levels were higher in invasive tumors than those in non-invasive tumors. Cell proliferation inhibition, increased apoptosis, and decreased motility were observed in FGFR3-AS1 siRNA-transfected T24 and 5637 cell lines. CONCLUSIONS: FGFR3-AS1 plays an oncogenic role in human bladder cancer. Knockdown of FGFR3-AS1 may provide a potential new therapeutic approach to this disease.