Calli, Aylin Orgen; Issin, Gizem; Yilmaz, Ismail; Ince, Dilek; Tural, Ersin; Guzelis, Ismail; Cecen, Refik Emre; Olgun, Hatice Nur; Gokcay, Deniz; Ozer, Erdener

Background: Wilms tumor is the most common cancer of the kidney that occurs during childhood, and histologically, it mimics renal embryogenesis. With the development and improvement of up-to-date treatment protocols, the survival rates of Wilms tumor have increased. However, metastases or local relapses are still observed in 15% of patients. The search for reliable biomarkers to identify at-risk patients is ongoing to predict the variability in treatment success. Currently, the evaluation of clinical, histopathological and genetic features are common diagnostic methods; however, epigenetic features can be examined with microRNA expression analyses and might allow us to comment on the behavior of the tumor and treatment response. Methods: In this study, we aimed to evaluate the relationship between microRNA-204 and microRNA-483-5p expression with clinicopathological data and the effect on Wilms tumor survival. For this purpose, the expression levels of RNU6B, microRNA-204 and microRNA-483-5p were evaluated in tumor and normal tissue by qreal time-polymerase chain reaction. We also investigated the relationship between microRNA expression levels with the clinicopathological and histological features of Wilms tumor. Results and conclusion: The results of our study indicate that the relative expression levels of microRNA-204 in Wilms tumor tissues were significantly lower than that in adjacent normal tissues. By contrast, tumor tissue had a higher microRNA-483-5p expression than the corresponding normal tissues. A statistically significant difference between microRNA-204 expression level with age and the presence of anaplasia was observed. The upregulation of microRNA-483-5p was found to have a significant correlation with patients after preoperative chemotherapy and complete tumor necrosis. Taken together, our data suggest that microRNA-204 could play a critical role as a tumor suppressor, whereas microRNA-483-5p acts as an oncogene in Wilms tumor progression. More importantly, microRNA-204 might be a novel predictive biomarker for anaplastic histology and could be useful for developing therapeutic interventions targeting this marker.