EIF2C, Dicer, and Drosha are up-regulated along tumor progression and associated with poor prognosis in bladder carcinoma.

ABSTRACT

EIF2C, Dicer, and Drosha are microRNA-regulating machinery components, which participate in microRNA intracellular process and transfer. Our research demonstrated the expression and clinical role of the microRNA-regulating machinery in bladder cancer. EIF2C1, EIF2C2, Dicer, and Drosha mRNA and protein levels were analyzed in 100 bladder carcinomas and 50 normal bladder tissues using quantitative polymerase chain reaction and Western blotting. EIF2C2, Dicer, and Drosha mRNAs and proteins were overexpressed in carcinoma compared with normal tissues, whereas EIF2C1 mRNA and protein were not obviously different. Moreover, immunohistochemistry was used to detect the expressions of EIF2C2, Dicer, and Drosha in 100 bladder carcinomas. There were higher EIF2C2, Dicer, and Drosha expressions in carcinomas than in the adjacent normal tissues, positive correlations being noted with clinical stage, histopathologic grade, and recurrence. Higher EIF2C2, Dicer, and Drosha expressions were related to shorter cancer-specific survival and shorter recurrence-free survival. Multivariate Cox analysis showed that EIF2C2 was an important risk factor in bladder cancer. In conclusion, EIF2C2, Dicer, and Drosha are more highly expressed in bladder carcinoma, promote the development of bladder cancer, and suggested a poor prognosis. Their clinical role in bladder carcinoma merits further research.