title: Octyl methoxycinnamate modulates gene expression and prevents cyclobutane pyrimidine dimer formation but not oxidative DNA damage in UV-exposed human cell lines.
abstract: Octyl methoxycinnamate (OMC) is one of the most widely used sunscreen ingredients. To analyze biological effects of OMC, an in vitro approach was used implying ultraviolet (UV) exposure of two human cell lines, a primary skin fibroblast (GM00498) and a breast cancer (MCF-7) cell lines. End points include cell viability assessment, assay of cyclobutane pyrimidine dimers (CPDs) and oxidated DNA lesions using alkaline elution and lesion-specific enzymes, and gene expression analysis of a panel of 17 DNA damage-responsive genes. We observed that OMC provided protection against CPDs, and the degree of protection correlated with the OMC-mediated reduction in UV dose. No such protection was found with respect to oxidative DNA lesions. Upon UV exposure in the presence of OMC, the gene expression studies showed significant differential changes in some of the genes studied and the expression of p53 protein was also changed. For some genes, the change in expression seemed to be delayed in time by OMC. The experimental approach applied in this study, using a panel of 17 genes in an in vitro cellular system together with genotoxicity assays, may be useful in the initial screening of active ingredients in sunscreens.
authors.affiliation: Department of Chemical Toxicology, Division of Environmental Medicine, Norwegian Institute of Public Health, Nydalen, NO-0403 Oslo, Norway.
authors.forename: Nur
authors.initials: N
authors.lastname: Duale
authors.forename: Ann-Karin
authors.initials: AK
authors.lastname: Olsen
authors.forename: Terje
authors.initials: T
authors.lastname: Christensen
authors.forename: Shamas T
authors.initials: ST
authors.lastname: Butt
authors.forename: Gunnar
authors.initials: G
authors.lastname: Brunborg
mesh_terms: D001943:Breast Neoplasms / Q000188:drug therapy / Q000235:genetics / Q000532:radiotherapy; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects / Q000528:radiation effects; D002934:Cinnamates / Q000494:pharmacology*; D004249:DNA Damage / Q000187:drug effects*; D004273:DNA, Neoplasm / Q000187:drug effects / Q000528:radiation effects; D005260:Female; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects; D005786:Gene Expression Regulation / Q000187:drug effects* / Q000528:radiation effects; D006801:Humans; D018384:Oxidative Stress / Q000187:drug effects / Q000528:radiation effects; D011740:Pyrimidine Dimers / Q000378:metabolism* / Q000528:radiation effects; D013473:Sunscreening Agents / Q000494:pharmacology*; D014466:Ultraviolet Rays
chemical_list: D002934:Cinnamates; D004273:DNA, Neoplasm; D011740:Pyrimidine Dimers; D013473:Sunscreening Agents; C118580:octylmethoxycinnamate