Deciphering the role of vitamin D on skin cancers and tumour microenvironment

Skin cancer is a significant health burden being the fourth most common cancer globally and accounts for 6.2% of the total combined cancer cases. However, mortality rates due to skin cancer are less when compared with other cancers, but it is significantly high in the Asian population (43%). DNA mutations and environmental and genetic factors are linked with skin cancer prognosis; however, long-term exposure to ultraviolet (UV) radiation remains one of the leading factors worldwide. Sun exposure is a major environmental risk factor for skin cancers but is also an essential source of vitamin D. On the other hand, studies exploring the relationship between skin cancer risk and vitamin D show mixed, somewhat conflicting results. This study investigates the role of vitamin D and skin carcinogenesis to clarify the associations. Moreover, in addition to suppressing cancer stem cells, it has been observed that vitamin D also regulates tumor initiation and metastasis. In conclusion, the incorporation of well-designed studies on the metabolism of vitamin D from a genotypic and phenotypic perspective is required to understand the intricate mechanisms linking the role of vitamin D in skin carcinogenesis. These new findings will open up new pathways in targeting the disease and lead to novel opportunities for its treatment and cure.