The Tumor Suppressor Actions of the Vitamin D Receptor in Skin

The study investigated the role of the vitamin D receptor (VDR) in skin tumor suppression, particularly in relation to the hedgehog (HH) and wnt/β-catenin pathways. Mice lacking VDR were more prone to tumor formation when exposed to chemical and UVB-induced mutations. Researchers created genetically modified mice to either activate or inactivate these pathways and observed significant disruptions in hair follicles and their cycling. The study found that even with the deletion of β-catenin, tumors still developed, suggesting that β-catenin deletion did not provide the anticipated protective effect against tumor formation. The acute response to UVB in these models was also evaluated, but results were not yet available.