Prevention of DNA damage in human skin by topical sunscreens.
OBJECTIVE
There is strong evidence that topical sunscreens, designed to protect against ultraviolet radiation (UVR)-induced erythema, decrease the amount of UVR to which the skin is exposed, but their effectiveness in reducing UVR-induced DNA damage in vivo has not been well quantified.


METHODS
We systematically reviewed the published literature (1990-2015) to determine whether sunscreens prevent DNA damage in human skin when applied prior to UVR exposure. We included experimental studies measuring UVR-induced DNA damage in human skin in vivo with and without sunscreens and excluded studies conducted in animal models and cell lines. Eligible studies were identified by computerized search of bibliographic databases, supplemented by hand-searching the reference lists of retrieved articles.


RESULTS
We identified ten eligible studies. Despite heterogeneity in methodological approaches, including the sun protection factors of the sunscreens assessed, range of skin types examined, the UVR exposure time and dose, the timing of post-irradiation biopsies and in the markers of DNA damage examined, all studies reported markedly reduced (or nil) UVR-induced DNA damage on sunscreen-protected skin.


CONCLUSIONS
Our review of the experimental evidence supports a protective effect of topical sunscreens in preventing UVR-induced DNA damage in human skin cells in vivo.
Population Health Department, QIMR Berghofer Medical Research Institute, Herston, Qld, Australia.|School of Public Health, the University of Queensland, Herston, Qld, Australia.
Catherine M
http://orcid.org/0000-0003-4483-1888
CM
Olsen
Population Health Department, QIMR Berghofer Medical Research Institute, Herston, Qld, Australia.
Louise F
LF
Wilson
Population Health Department, QIMR Berghofer Medical Research Institute, Herston, Qld, Australia.|School of Public Health, the University of Queensland, Herston, Qld, Australia.|Cancer Research UK Manchester Institute and Institute of Inflammation and Repair, University of Manchester, Manchester, UK.
Adèle C
AC
Green
Population Health Department, QIMR Berghofer Medical Research Institute, Herston, Qld, Australia.
Neela
N
Biswas
Population Health Department, QIMR Berghofer Medical Research Institute, Herston, Qld, Australia.
Juhi
J
Loyalka
Population Health Department, QIMR Berghofer Medical Research Institute, Herston, Qld, Australia.|School of Public Health, the University of Queensland, Herston, Qld, Australia.
David C
DC
Whiteman
D004249:DNA Damage / Q000187:drug effects* / Q000528:radiation effects*; D006801:Humans; D013473:Sunscreening Agents / Q000494:pharmacology*; D014466:Ultraviolet Rays / Q000009:adverse effects*
D013473:Sunscreening Agents
DNA damage; melanoma; sunscreen; ultraviolet