RARB (Retinoic Acid Receptor Beta): RARB is a nuclear receptor that binds retinoic acid, a metabolite of vitamin A. It plays a crucial role in regulating gene expression during development, particularly in epithelial tissue growth, cell differentiation, and the formation of the nervous system. Altered RARB activity has been linked to cancers such as skin, lung, and breast cancer, as well as developmental disorders, and is being investigated for potential retinoid-based therapies.