CDK4 and hyperparathyroidism: miR-664 was predicted to target the CDC73 tumor suppressor gene, whose germinal inactivating mutations are responsible for the hyperparathyroidism-jaw tumor syndrome [61] and somatic mutations have been associated with the development of sporadic parathyroid carcinoma [62], and the CDKN2C tumor suppressor gene encoding the p18ink4c, an inhibitor of the cyclin kinases CDK4 and CDK6, that negatively controls the cell cycle G1 progression.