MiR-224-5p, the most up-regulated miR in nodules (+254 fold vs. controls), was recently shown to target deiodinase 1 (Dio1), an enzyme expressed in the liver and kidney and required for the conversion of T4 to T3 in rat hepatocytes and human renal carcinoma cells (47, 48). This evidence concerns the gene DIO1 and renal carcinoma.