Graying hair and cancer can be two opposite results of the same cellular process. Researchers at the University of Tokyo have found that melanocyte cells (McSCs), which produce pigment in hair and skin, respond to stress in different ways. DNA damage from double-strand breaks causes senescence-related differentiation (seno-differentiation) and causes stem cells to permanently mature and lose gray hair. In contrast, exposure to certain carcinogens or UVB radiation allows McSCs to bypass this defense mechanism, continue self-renewal, and expand, increasing the risk of melanoma.
Professor Emi Nishimura says: “These findings suggest that the same population of stem cells can follow antagonistic fates, exhaustion or expansion, depending on the type of stress and microenvironmental signals.” The study, published in Nature Cell Biology, links hair graying to a natural defense that destroys damaged cells before they become cancerous, and suggests that a failure of this defense can contribute to the development of melanoma.
Source: Institute of Medical Science, University of Tokyo
This article is in Journal of Wellbeing 222
