SOX21 and neoplasm: In order to know the clinical value of SOX21-AS1 in patients with nephroblastoma, all nephroblastoma patients were classified into different groups based on clinicopathological features including tumor size (<5 cm vs. ≥5 cm), NWTS (National Wilms Tumor Study) stage (I-II vs. III-IV) and histopathological type (favorable vs. unfavorable).