Expression and potential role of miRNA-20a in bladder cancer / 中国肿瘤临床

ABSTRACT

Objective:To investigate microRNA-20a (miRNA-20a) expression in bladder cancer and its potential mechanism. Methods:MiRNA-20a expression was examined using quantitative reverse-transcription polymerase chain reaction (qRT-PCR) in human bladder cancer tissues and the paired adjacent non-tumor bladder tissues of 96 patients. The target gene of the miRNA-20a was predicted and validated using bioinformatics analysis and reporter gene assay, respectively. The mRNA or protein expression of the target gene in bladder cancer T24 and J82 cells transfected with miRNA-20a mimic or negative control (NC) mimics was detected via qRT-PCR, West-ern blot analysis, and cell immunofluorescence. CCK-8, Transwell chamber, and wound-healing assays were applied to test the prolifer-ation, migration, and invasion of T24 cells after miRNA-20a over-expression in vitro. Results:MiRNA-20a expression significantly in-creased in bladder cancer tissues compared with those in corresponding adjacent non-tumor tissues. High miRNA-20a expression in bladder cancer tissues was closely related to aggressive tumor phenotype, such as high histological grade, poor TNM stage, lymph node invasion, distant metastasis, and tumor recurrence (all P<0.001). Dual-luciferase reporter assay confirmed that miRNA-20a can di-rectly bind to the 3'-untranslated region (3'-UTR) of Homo sapiens longevity assurance homologue 2 (LASS2). Transfection with miRNA-20a mimics significantly inhibited mRNA and protein expression of LASS2 in T24 and J82 cells (all P<0.01) and promoted T24 cell prolif-eration, migration, and invasion in vitro. Conclusion:MiRNA-20a is highly expressed in bladder cancer tissues. MiRNA-20a enhances cell migration as well as proliferation and acts as an oncogene in bladder cancer because of the targeted inhibition of LASS2 expression.