An explanation of assymetric distribution of melanin in the epidermis !

The skin performs important function, including sun protection. Melanin distribution in the epidermis plays a role in photoprotection. Solar radiations induced epidermal DNA damages, mostly in the basal layer, and is an established caused of keratinocytes cancers. Melanin distribution in human epidermis is essentialy located in the basal layer. However, Read more…

3D reconstruction X63

P. acnes inhibits human melanocytes survival after UVB radiation which could prevent melanoma-genesis causes by DNA damage

Melanoma is a type of skin cancer that develops from cells called melanocytes, is one of the fastest-growing and deadliest cancer in the world. It usually caused by DNA damage resulting from exposure to ultraviolet (UV) light from the sun. P. acnes is a ubiquitous gram-positive anaerobic bacterium present in Read more…

A representative hematoxylin and eosin staining of UV-induced skin tumor or skin obtained from SKH-1 mice colonized by S. epidermidis 1457 or MO34, respectively, treated with UV-B for 12 weeks.

Could skin microbiota reduce cancer risk?

Researchers from the Department of Dermatology of the University of California have a commensal strain of Staphylococcus epidermidis that protects against skin neoplasia. This strain produces 6-N-hydroxyaminopurine (6-HAP), a molecule that inhibits DNA polymerase activity. Mice colonized with this strain have a reduced incidence of ultraviolet-induced tumors compared to control mice (colonized with Read more…