Molecular mechanisms of UV-induced apoptosis

Sunburn cells, single standing cells with typical morphologic features occu rring in UV-exposed skin, have been recognized as keratinocytes undergoing apoptosis following UV irradiation, Induction of apoptosis following UV exp osure appears to be a protective mechanism, getting rid off severely damage d cells that bear the risk of malignant transformation. UV-mediated apoptos is is a highly complex process in which different molecular pathways are in volved. These include DNA damage, activation of the tumor suppressor gene p 53, triggering of cell death receptors either directly by UV or by autocrin e release of death ligands, mitochondrial damage and cytochrome C release. Detailed knowledge about the interplay between these pathways will increase our understanding of photocarcinogenesis. This review briefly discusses re cent findings concerning the molecular mechanisms underlying UV-induced apo ptosis.