Correlation Analysis of miR-20a Expression and Relapse in Formalin-fixed Paraffinembedded Tissue of Urothelial Carcinoma of Bladder

Objective To investigate the feasibility of extracting microRNA from formalin-fixed paraffinembedded(FFPE) tissue of bladder urothelial carcinoma(UC), and analyze the correlation among miR-20a expression, clinicopathologic feature and the relapse. Methods The expression levels of miR-20a in freshly frozen(FF) and FFPE tissues from 50 cases of bladder UC were detected by quantitative real-time PCR. The expression levels of miR-20a in FFPE tissue from 181 cases of bladder UC and its correlation with the relapse in different years were analyzed. Results The expression of miR-20a were closely correlated in FFPE and FF tissue(r=0.792,P＜0.001). The expression levels of miR-20a in FFPE tissue in different years were stable (P＞0.05). The expression of miR-20a was closely correlated with clinicopathological features. The relapse rate of patients with high expression of miR-20a was signifi cantly higher(P＜0.05). Conclusion The expression levels of miR-20a in FF and FFPE tissue of bladder UC were consistency and reliable, hence, it is feasible to extract and study the microRNA in FFPE tissues. The role of miR-20a was correlated with its expression level, and a high expression level is the independent factor of postoperative relapse.