Abstract
BACKGROUND: Long noncoding RNAs (lncRNAs) play critical and complex roles in regulating various biological processes of cancers. Our study aimed to investigate the involvement of lncRNA NCK1-AS1 in urinary bladder cancer (UBC). METHODS: qRT-PCR was used to detect the expression of lncRNA NCK1-AS1 and miR-143 in UBC tissues and cells. The dual-luciferase reporter system assays were used to confirm the interaction between NCK1-AS1 and miR-143, and flow cytometry assays were applied to examine the behavioral changes in HT-1376 and HT-1197 cell lines. RESULTS: It was observed that NCK1-AS1 was up-regulated, while miR-143 was down-regulated in tumor tissues than in adjacent healthy tissues of urinary bladder cancer (UBC) patients. A 5-year survival analysis showed that the survival rate of patients with high NCK1-AS1 level or low miR-143 level in tumor tissues appears relatively low. Correlation analysis revealed a significant inverse correlation between NCK1-AS1 and miR-143 in tumor tissues. Over-expression NCK1-AS1 reduced the expression level of miR-143, while elevating the level of miR-143 failed to affect NCK1-AS1 expression. NCK1-AS1 over-expression led to promoted proliferation and increased percentage of CD133+ (stemness) cells. CONCLUSION: Therefore, NCK1-AS1 promotes cancer cell proliferation and increases cell stemness in UBC patients by down-regulating miR-143.