Association of Indoor Tanning Exposure With Age at Melanoma Diagnosis and BRAF V600E Mutations.
Ontology highlight
ABSTRACT:
SUBMITTER: Burbidge TE
PROVIDER: S-EPMC6855935 | biostudies-literature |
REPOSITORIES: biostudies-literature
Similar Datasets
Project description:To examine the association between level and patterns of baseline intra-tumoural BRAF(V600E) protein expression and clinical outcome of BRAF(V600E) melanoma patients treated with selective BRAF inhibitors.Fifty-eight BRAF(V600E) metastatic melanoma patients treated with dabrafenib or vemurafenib on clinical trials had pre-treatment tumour BRAF(V600E) protein expression immunohistochemically (IHC) assessed using the BRAF V600E mutant-specific antibody VE1. Sections were examined for staining intensity (score 1-3) and percentage of immunoreactive tumour cells, and from this an immunoreactive score (IRS) was derived (intensity × per cent positive/10). The presence of intra-tumoural heterogeneity for BRAF(V600E) protein expression was also assessed. BRAF(V600E) expression was correlated with RECIST response, time to best response (TTBR), progression-free survival (PFS) and overall survival (OS).Expression was generally high (median IRS 28 (range 5-30)) and homogeneous (78%). Expression of mutated protein BRAF(V600E) as measured by intensity, per cent immunoreactive cells, or IRS did not correlate with RECIST response, TTBR, PFS or OS, including on multivariate analysis. Heterogeneity of staining was seen in 22% of cases and did not correlate with outcome.In the current study population, IHC-measured pre-treatment BRAF(V600E) protein expression does not predict response or outcome to BRAF inhibitor therapy in BRAF(V600E) metastatic melanoma patients.
| S-EPMC3590666 | biostudies-other
Project description:Here, we identify a panel of melanoma lines with non-V600E mutations in BRAF. These G469E- and D594G-mutated melanomas were found to exhibit constitutive levels of phospho-extracellular signal-regulated kinase (pERK) and low levels of phospho-mitogen-activated protein kinase/ERK kinase (pMEK) and were resistant to MEK inhibition. Upon treatment with the CRAF inhibitor sorafenib, these lines underwent apoptosis and associated with mitochondrial depolarization and relocalization of apoptosis-inducing factor, whereas the BRAF-V600E-mutated melanomas did not. Studies have shown low-activity mutants of BRAF (G469E/D594G) instead signal through CRAF. Unlike BRAF, CRAF directly regulates apoptosis through mitochondrial localization where it binds to Bcl-2 and phosphorylates BAD. The CRAF inhibitor sorafenib was found to induce a time-dependent reduction in both BAD phosphorylation and Bcl-2 expression in the D594G/G469E lines only. Knockdown of CRAF using a lentiviral shRNA suppressed both Bcl-2 expression and induced apoptosis in the D594G melanoma line but not in a V600E-mutated line. Finally, we showed in a series of xenograft studies that sorafenib was more potent at reducing the growth of tumors with the D594G mutation than those with the V600E mutation. In summary, we have identified a group of melanomas with low-activity BRAF mutations that are reliant upon CRAF-mediated survival activity.
| S-EPMC2898184 | biostudies-literature
Project description:Acral melanoma, a distinct form of cutaneous melanoma originating in the glabrous skin of the palms, soles, and nail beds, has a different genetic background from other subtypes of cutaneous melanoma. The roles of oncogenic BRAF mutations of acral melanoma in pathogenesis and patient outcomes have not been fully elucidated. We retrieved a total of 112 patients with primary acral melanoma and checked their BRAF V600E status using immunohistochemical staining of VE1 antibody. Among these cases, 21 acral melanoma samples (18.8%) showed positive BRAF V600E staining, and of those, 11 samples (9.8%) showed a heterogeneous staining pattern, with a mixture of VE1-positive and VE1-negative cells. BRAF V600E positivity was significantly associated with thicker melanoma (p = 0.0015). There was no significant difference in clinicopathological factors between homogeneous and heterogeneous VE1-positive acral melanoma. Both patients with BRAF V600E-positive acral melanoma and those with heterogeneous BRAF V600E had significantly shorter melanoma-specific survival than those with BRAF V600E-negative melanoma in Kaplan-Meier analysis (p = 0.0283 and p = 0.0065, respectively). These findings provide novel insights into the pathobiology of acral melanoma.
| S-EPMC7141227 | biostudies-literature
Project description:Although ultraviolet radiation (UV) exposure from indoor tanning has been linked to an increased risk of melanoma, the role of DNA repair genes in this process is unknown. We evaluated the association of 92 single nucleotide polymorphisms (SNPs) in 20 DNA repair genes with the risk of melanoma and indoor tanning among 929 patients with melanoma and 817 controls from the Minnesota Skin Health Study. Significant associations with melanoma risk were identified for SNPs in ERCC4, ERCC6, RFC1, XPC, MGMT, and FBRSL1 genes; with a cutoff of P < 0.05. ERCC6 and FBRSL1 gene variants and haplotypes interacted with indoor tanning. However, none of the 92 SNPs tested met the correction criteria for multiple comparisons. This study, based on an a priori interest in investigating the role of DNA repair capacity using variants in base excision and nucleotide excision repair, identified several genes that may play a role in resolving UV-induced DNA damage.
| S-EPMC3752318 | biostudies-literature
Project description:ObjectiveTo assess whether an association exists between financial links to the indoor tanning industry and conclusions of indoor tanning literature.DesignSystematic review.Data sourcesPubMed, Embase, and Web of Science, up to 15 February 2019.Study selection criteriaArticles discussing indoor tanning and health were eligible for inclusion, with no article type restrictions (original research, systematic reviews, review articles, case reports, editorials, commentaries, and letters were all eligible). Basic science studies, articles describing only indoor tanning prevalence, non-English articles, and articles without full text available were excluded.Results691 articles were included in analysis, including empiric articles (eg, original articles or systematic reviews) (357/691; 51.7%) and non-empiric articles letters (eg, commentaries, letters, or editorials) (334/691; 48.3%). Overall, 7.2% (50/691) of articles had financial links to the indoor tanning industry; 10.7% (74/691) articles favored indoor tanning, 3.9% (27/691) were neutral, and 85.4% (590/691) were critical of indoor tanning. Among the articles without industry funding, 4.4% (27/620) favored indoor tanning, 3.5% (22/620) were neutral, and 92.1% (571/620) were critical of indoor tanning. Among the articles with financial links to the indoor tanning industry, 78% (39/50) favored indoor tanning, 10% (5/50) were neutral, and 12% (6/50) were critical of indoor tanning. Support from the indoor tanning industry was significantly associated with favoring indoor tanning (risk ratio 14.3, 95% confidence interval 10.0 to 20.4).ConclusionsAlthough most articles in the indoor tanning literature are independent of industry funding, articles with financial links to the indoor tanning industry are more likely to favor indoor tanning. Public health practitioners and researchers need to be aware of and account for industry funding when interpreting the evidence related to indoor tanning.Systematic review registrationPROSPERO CRD42019123617.
| S-EPMC7190068 | biostudies-literature
Project description:The discovery of activating BRAF V600E mutations in 50% of all cutaneous melanomas has revolutionized the understanding of melanoma biology and provided new strategies for the therapeutic management of this deadly disease. Highly potent small molecule inhibitors of BRAF are now showing great promise as a novel therapeutic strategy for melanomas harboring activating BRAF V600E mutations and are associated with high levels of response. This commentary article discusses the latest data on the role of mutated BRAF in the development and progression of melanoma as the basis for understanding the mechanism of action of BRAF inhibitors in the preclinical and clinical settings. We further address the issue of BRAF inhibitor resistance and outline the latest insights into the mechanisms of therapeutic escape as well as describing approaches to prevent and abrogate the onset of both intrinsic and acquired drug resistance. It is likely that our evolving understanding of melanoma genetics and signaling will allow for the further personalization of melanoma therapy with the goal of improving clinical responses.
| S-EPMC4001781 | biostudies-literature
Project description:BackgroundMost mutations in melanoma affect one critical amino acid on BRAF gene, resulting in the V600E substitution. Patient management is often based on the use of specific inhibitors targeting this mutation.MethodsDNA and RNA mutation status was assessed in 15 melanoma cell lines by Sanger sequencing and RNA-seq. We tested the cell lines responsiveness to BRAF inhibitors (vemurafenib and PLX4720, BRAF-specific and sorafenib, BRAF non-specific). Cell proliferation was assessed by MTT colorimetric assay. BRAF V600E RNA expression was assessed by qPCR. Expression level of phosphorylated-ERK protein was assessed by Western Blotting as marker of BRAF activation.ResultsThree cell lines were discordant in the mutation detection (BRAF V600E at DNA level/Sanger sequencing and BRAF WT on RNA-seq). We initially postulated that those cell lines may express only the WT allele at the RNA level although mutated at the DNA level. A more careful analysis showed that they express low level of BRAF RNA and the expression may be in favor of the WT allele. We tested whether the discordant cell lines responded differently to BRAF-specific inhibitors. Their proliferation rate decreased after treatment with vemurafenib and PLX4720 but was not affected by sorafenib, suggesting a BRAF V600E biological behavior. Yet, responsiveness to the BRAF specific inhibitors was lower as compared to the control. Western Blot analysis revealed a decreased expression of p-ERK protein in the BRAF V600E control cell line and in the discordant cell lines upon treatment with BRAF-specific inhibitors. The discordant cell lines showed a lower responsiveness to BRAF inhibitors when compared to the BRAF V600E control cell line. The results obtained from the inhibition experiment and molecular analyses were also confirmed in three additional cell lines.ConclusionCell lines carrying V600E mutation at the DNA level may respond differently to BRAF targeted treatment potentially due to a lower V600E RNA expression.
| S-EPMC7216681 | biostudies-literature
Project description:ObjectiveTo synthesise the literature on indoor tanning and non-melanoma skin cancer.DesignSystematic review and meta-analysis.Data sourcesPubMed (1966 to present), Embase (1974 to present), and Web of Science (1898 to present).Study selectionAll 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 extractionTwo 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.Results12 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).ConclusionsIndoor 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.
| S-EPMC3462818 | biostudies-literature
Project description:Although nearly half of human melanomas harbor oncogenic BRAF(V600E) mutations, the genetic events that cooperate with these mutations to drive melanogenesis are still largely unknown. Here we show that Sleeping Beauty (SB) transposon-mediated mutagenesis drives melanoma progression in Braf(V600E) mutant mice and identify 1,232 recurrently mutated candidate cancer genes (CCGs) from 70 SB-driven melanomas. CCGs are enriched in Wnt, PI3K, MAPK and netrin signaling pathway components and are more highly connected to one another than predicted by chance, indicating that SB targets cooperative genetic networks in melanoma. Human orthologs of >500 CCGs are enriched for mutations in human melanoma or showed statistically significant clinical associations between RNA abundance and survival of patients with metastatic melanoma. We also functionally validate CEP350 as a new tumor-suppressor gene in human melanoma. SB mutagenesis has thus helped to catalog the cooperative molecular mechanisms driving BRAF(V600E) melanoma and discover new genes with potential clinical importance in human melanoma.
| S-EPMC4844184 | biostudies-literature
Project description:Ameloblastoma is a benign but locally infiltrative odontogenic neoplasm. Although ameloblastomas rarely metastasise, recurrences together with radical surgery often result in facial deformity and significant morbidity. Development of non-invasive therapies has been precluded by a lack of understanding of the molecular background of ameloblastoma pathogenesis. When addressing the role of ERBB receptors as potential new targets for ameloblastoma, we discovered significant EGFR over-expression in clinical samples using real-time RT-PCR, but observed variable sensitivity of novel primary ameloblastoma cells to EGFR-targeted drugs in vitro. In the quest for mutations downstream of EGFR that could explain this apparent discrepancy, Sanger sequencing revealed an oncogenic BRAF V600E mutation in the cell line resistant to EGFR inhibition. Further analysis of the clinical samples by Sanger sequencing and BRAF V600E-specific immunohistochemistry demonstrated a high frequency of BRAF V600E mutations (15 of 24 samples, 63%). These data provide novel insight into the poorly understood molecular pathogenesis of ameloblastoma and offer a rationale to test drugs targeting EGFR or mutant BRAF as novel therapies for ameloblastoma.
| S-EPMC4255689 | biostudies-literature