Molecular cystoscopy: Micro-RNAs could be a marker for identifying genotypic changes for transitional cell carcinoma of the urinary bladder

INTRODUCTION: Normal-looking mucosa may harbor genetic changes preceding a visible tumor. This study was aimed at exploring the role of the quantitative expression of micro-RNAs (miRNAs) in bladder cancer tissue in comparison with normal mucosa and healthy controls (HCs) as a molecular marker. MATERIALS AND METHODS: Between October 2011 to December 2012, tissue from the bladder tumor of 21 patients (cases tumor, CT), normal mucosa (case control, CC) of the same patients (n-21) and normal bladder mucosa from 10 HCs were obtained. miRNAs of angiogenesis, endothelial mesenchymal transition and apoptosis were quantified using stem–loop RT Taq Man polymerase chain reaction. Statistical analysis was performed using the Chi square and independent sample T tests by using SPSS version 16. RESULTS: The mean age of the patients and controls were 55.41 ± 11.03 and 52.14 ± 13.04 years. miR-21, miR-205, miR-126, miR-10b and miR-200a were highly expressed in CT (P < 0.027, <0.048, <0.025, <0.029 and < 0.005) as compared with HC. Expression of miR-21 and miR-129 were both correlated with grade and stage (P = 0.001 and < 0.009, respectively) and the level of expression was different in the same grade of non-muscle invasive tumors. The fold change of miR129, miR205 and miR200a was significantly higher in the normal-looking mucosa of bladder tumor patients than the HC (P < 0.005). CONCLUSION: Expression of miR129, miR205 and miR200a in the normal-looking mucosa of bladder cancer patients was significantly higher than the normal mucosa of a HC. This may help in predicting recurrence and formulating the follow-up strategy.