Aberrant DNA methylation is an epigenetic hallmark of melanoma, known to play important roles in melanoma formation and progression.,Recent advances in genome-wide methylation methods have provided the means to identify differentially methylated genes, methylation signatures, and potential biomarkers.,However, despite considerable effort and advances in cataloging methylation changes in melanoma, many questions remain unanswered.,The aim of this review is to summarize recent developments, emerging trends, and important unresolved questions in the field of aberrant DNA methylation in melanoma.,In addition to reviewing recent developments, we carefully synthesize the findings in an effort to provide a framework for understanding the current state and direction of the field.,To facilitate clarity, we divided the review into DNA methylation changes in melanoma, biomarker opportunities, and therapeutic developments.,We hope this review contributes to accelerating the utilization of the diagnostic, prognostic, and therapeutic potential of DNA methylation for the benefit of melanoma patients.
Objective To synthesise the literature on indoor tanning and non-melanoma skin cancer.,Design Systematic review and meta-analysis.,Data sources PubMed (1966 to present), Embase (1974 to present), and Web of Science (1898 to present).,Study selection All articles that reported an original effect statistic for indoor tanning and non-melanoma skin cancer were included.,Articles that presented no data, such as review articles and editorials, were excluded, as were articles in languages other than English.,Data extraction Two investigators independently extracted data.,Random effects meta-analysis was used to summarise the relative risk of ever use versus never use of indoor tanning.,Dose-response effects and exposure to indoor tanning during early life were also examined.,The population attributable risk fraction for the United States population was calculated.,Results 12 studies with 9328 cases of non-melanoma skin cancer were included.,Among people who reported ever using indoor tanning compared with those who never used indoor tanning, the summary relative risk for squamous cell carcinoma was 1.67 (95% confidence interval 1.29 to 2.17) and that for basal cell carcinoma was 1.29 (1.08 to 1.53).,No significant heterogeneity existed between studies.,The population attributable risk fraction for the United States was estimated to be 8.2% for squamous cell carcinoma and 3.7% for basal cell carcinoma.,This corresponds to more than 170 000 cases of non-melanoma skin cancer each year attributable to indoor tanning.,On the basis of data from three studies, use of indoor tanning before age 25 was more strongly associated with both squamous cell carcinoma (relative risk 2.02, 0.70 to 5.86) and basal cell carcinoma (1.40, 1.29 to 1.52).,Conclusions Indoor tanning is associated with a significantly increased risk of both basal and squamous cell skin cancer.,The risk is higher with use in early life (<25 years).,This modifiable risk factor may account for hundreds of thousands of cases of non-melanoma skin cancer each year in the United States alone and many more worldwide.,These findings contribute to the growing body of evidence on the harms of indoor tanning and support public health campaigns and regulation to reduce exposure to this carcinogen.