[show abstract][hide abstract] ABSTRACT: Dysplastic nevi (DN) is a strong risk factor for cutaneous malignant melanoma (CMM), and it frequently occurs in melanoma-prone families. To identify genetic variants for DN, we genotyped 677 tagSNPs in 38 melanoma candidate genes that are involved in pigmentation, DNA repair, cell cycle control, and melanocyte proliferation pathways in a total of 504 individuals (310 with DN, 194 without DN) from 53 melanoma-prone families (23 CDKN2A mutation positive and 30 negative). Conditional logistic regression, conditioning on families, was used to estimate the association between DN and each SNP separately, adjusted for age, sex, CMM and CDKN2A status. P-values for SNPs in the same gene were combined to yield gene-specific p-values. Two genes, CDK6 and XRCC1, were significantly associated with DN after Bonferroni correction for multiple testing (P=0.0001 and 0.00025, respectively), whereas neither gene was significantly associated with CMM. Associations for CDK6 SNPs were stronger in CDKN2A mutation positive families (rs2079147, Pinteraction=0.0033), whereas XRCC1 SNPs had similar effects in mutation-positive and negative families. The association for one of the associated SNPs in XRCC1 (rs25487) was replicated in two independent datasets (random effect meta-analysis: P<0.0001). Our findings suggest that some genetic variants may contribute to DN risk independently of their association with CMM in melanoma-prone families.Journal of Investigative Dermatology accepted article preview online, 26 July 2013. doi:10.1038/jid.2013.316.
Journal of Investigative Dermatology 07/2013; · 6.19 Impact Factor
[show abstract][hide abstract] ABSTRACT: We report the results of an association study of melanoma that is based on the genome-wide imputation of the genotypes of 1,353 cases and 3,566 controls of European origin conducted by the GenoMEL consortium. This revealed an association between several SNPs in intron 8 of the FTO gene, including rs16953002, which replicated using 12,313 cases and 55,667 controls of European ancestry from Europe, the USA and Australia (combined P = 3.6 × 10-12, per-allele odds ratio for allele A = 1.16). In addition to identifying a new melanoma-susceptibility locus, this is to our knowledge the first study to identify and replicate an association with SNPs in FTO not related to body mass index (BMI). These SNPs are not in intron 1 (the BMI-related region) and exhibit no association with BMI. This suggests FTO's function may be broader than the existing paradigm that FTO variants influence multiple traits only through their associations with BMI and obesity.
[show abstract][hide abstract] ABSTRACT: BACKGROUND: Features associated with an increased frequency of cyclin-dependent kinase inhibitor 2A (CDKN2A) mutations have been identified in families with 3 or more patients with cutaneous melanoma (CM). However, in families with 2 patients with CM, which represent the majority of familial melanoma, these factors have been rarely studied. OBJECTIVE: We investigated association of 3 clinical features with the presence of a CDKN2A mutation in a family by extent of CM family clustering (2 vs ≥3 patients with CM among first-degree relatives in a family). METHODS: We included 483 French families that comprised 387 families with 2 patients with CM (F2 families) and 96 families with 3 or more patients with CM (F3+ families). Three clinical factors were examined individually and in a joint analysis: median age at diagnosis younger than 50 years, and 1 or more patient in a family with multiple primary melanoma or with pancreatic cancer. RESULTS: The frequency of CDKN2A mutations was higher in F3+ families (32%) than in F2 families (13%). Although early age at melanoma diagnosis and occurrence of multiple primary melanoma in 1 or more patient were significantly associated with the risk of a CDKN2A mutation in F2 families, early age at melanoma diagnosis and occurrence of pancreatic cancer in a family were significantly associated with CDKN2A mutations in F3+ families. LIMITATIONS: The study was not population based. CONCLUSIONS: This study shows that factors associated with CDKN2A mutations differ by extent of CM family clustering. It indicates that, in France, families with 2 patients with CM are eligible for genetic testing especially when there is an early age at CM diagnosis and/or 1 or more patients with multiple primary melanoma.
Journal of the American Academy of Dermatology 07/2012; · 4.91 Impact Factor
[show abstract][hide abstract] ABSTRACT: So far, no common environmental and/or phenotypic factor has been associated with melanoma and renal cell carcinoma (RCC). The known risk factors for melanoma include sun exposure, pigmentation and nevus phenotypes; risk factors associated with RCC include smoking, obesity and hypertension. A recent study of coexisting melanoma and RCC in the same patients supports a genetic predisposition underlying the association between these two cancers. The microphthalmia-associated transcription factor (MITF) has been proposed to act as a melanoma oncogene; it also stimulates the transcription of hypoxia inducible factor (HIF1A), the pathway of which is targeted by kidney cancer susceptibility genes. We therefore proposed that MITF might have a role in conferring a genetic predisposition to co-occurring melanoma and RCC. Here we identify a germline missense substitution in MITF (Mi-E318K) that occurred at a significantly higher frequency in genetically enriched patients affected with melanoma, RCC or both cancers, when compared with controls. Overall, Mi-E318K carriers had a higher than fivefold increased risk of developing melanoma, RCC or both cancers. Codon 318 is located in a small-ubiquitin-like modifier (SUMO) consensus site (ΨKXE) and Mi-E318K severely impaired SUMOylation of MITF. Mi-E318K enhanced MITF protein binding to the HIF1A promoter and increased its transcriptional activity compared to wild-type MITF. Further, we observed a global increase in Mi-E318K-occupied loci. In an RCC cell line, gene expression profiling identified a Mi-E318K signature related to cell growth, proliferation and inflammation. Lastly, the mutant protein enhanced melanocytic and renal cell clonogenicity, migration and invasion, consistent with a gain-of-function role in tumorigenesis. Our data provide insights into the link between SUMOylation, transcription and cancer.
[show abstract][hide abstract] ABSTRACT: Patients with melanoma (MM) have an increased risk of kidney cancer, and there is an excess risk of MM among patients with renal cell carcinoma (RCC). The objective of the current study was to analyze a series of 42 patients with both MM and RCC to identify clinical and pathologic features as well as risk factors of this association.
Clinical and pathologic characteristics of 42 patients who developed both MM and RCC (the MM + RCC series) were compared with 2 published series in each cancer alone: a series of 293 patients with MM (MM series) and a series of 1527 patients with RCC (RCC series).
RCC was diagnosed concomitantly or after MM in 83% of patients in the MM + RCC series. Those patients displayed a high proportion of asymptomatic RCC at diagnosis (70%) and a higher frequency of stage I tumors (61%) than patients in the RCC series. Compared with the MM series, patients in the MM + RCC series more often were men, had a higher frequency of blond/red hair, had poor tanning ability, and had a higher number of nevi. In addition, patients in the MM + RCC series had a high aggregation of other malignancies (mainly skin cancers) and a significantly higher frequency of family history of MM (P = .005). Only 2 cyclin-dependent kinase 2A gene (CDKN2A) germline mutations were identified among patients in the MM + RCC series who also were members of MM-prone families.
The high aggregation of cancers among patients in the MM + RCC series and the familial clustering of MM argued for a genetic predisposition that may be partly independent of CDKN2A.
Cancer 12/2010; 116(24):5716-24. · 5.20 Impact Factor
[show abstract][hide abstract] ABSTRACT: Carrying the cyclin-dependent kinase inhibitor 2A (CDKN2A) germline mutations is associated with a high risk for melanoma. Penetrance of CDKN2A mutations is modified by pigmentation characteristics, nevus phenotypes, and some variants of the melanocortin-1 receptor gene (MC1R), which is known to have a role in the pigmentation process. However, investigation of the associations of both MC1R variants and host phenotypes with melanoma risk has been limited.
We included 815 CDKN2A mutation carriers (473 affected, and 342 unaffected, with melanoma) from 186 families from 15 centers in Europe, North America, and Australia who participated in the Melanoma Genetics Consortium. In this family-based study, we assessed the associations of the four most frequent MC1R variants (V60L, V92M, R151C, and R160W) and the number of variants (1, ≥2 variants), alone or jointly with the host phenotypes (hair color, propensity to sunburn, and number of nevi), with melanoma risk in CDKN2A mutation carriers. These associations were estimated and tested using generalized estimating equations. All statistical tests were two-sided.
Carrying any one of the four most frequent MC1R variants (V60L, V92M, R151C, R160W) in CDKN2A mutation carriers was associated with a statistically significantly increased risk for melanoma across all continents (1.24 × 10(-6) ≤ P ≤ .0007). A consistent pattern of increase in melanoma risk was also associated with increase in number of MC1R variants. The risk of melanoma associated with at least two MC1R variants was 2.6-fold higher than the risk associated with only one variant (odds ratio = 5.83 [95% confidence interval = 3.60 to 9.46] vs 2.25 [95% confidence interval = 1.44 to 3.52]; P(trend) = 1.86 × 10(-8)). The joint analysis of MC1R variants and host phenotypes showed statistically significant associations of melanoma risk, together with MC1R variants (.0001 ≤ P ≤ .04), hair color (.006 ≤ P ≤ .06), and number of nevi (6.9 × 10(-6) ≤ P ≤ .02).
Results show that MC1R variants, hair color, and number of nevi were jointly associated with melanoma risk in CDKN2A mutation carriers. This joint association may have important consequences for risk assessments in familial settings.
[show abstract][hide abstract] ABSTRACT: The effect of CDKN2A, the major high-risk melanoma susceptibility gene, has been shown to be modified by host-related phenotypes and variants of MC1R gene. The glutathione S-transferase (GSTs) genes, implicated in detoxification of metabolites after UV exposure, are candidates for modulating CDKN2A penetrance. Few case-control studies have investigated the effect of GSTs on melanoma risk, and have led to controversial results while these genes have not yet been studied in CDKN2A melanoma-prone families. We examined the effect of GSTP1, GSTM1 and GSTT1 genotypes on melanoma risk in 25 multi-generational melanoma-prone families with CDKN2A mutations, in presence of MC1R gene variants, sun exposure, and host-related phenotypes. These data included 195 genotyped subjects for all studied genes. We applied the GEE (Generalized Estimating Equations) approach to test for the effect of GSTs while adjusting for age, sex and CDKN2A mutation status and including successively MC1R, sun exposure and host factors in the model. No significant effect of null GSTM1 allele and GSTP1 variants (p.I105V, p.A114V) on melanoma risk was found. However, a significant protective effect of carrying >or=1 null GSTT1 allele was shown: OR(adjusted for age,sex,CDKN2A ) = 0.41 (0.18-0.94) and OR(adjusted for age,sex,CDKN2A,MC1R ) = 0.24 (0.15-0.58). Altogether, the factors modifying significantly the melanoma risk associated with CDKN2A mutations (stepwise procedure) were: MC1R and dysplastic nevi (increasing the risk) and GSTT1 (decreasing the risk). This study shows that even when a high-risk gene (CDKN2A) has been identified, multiple genetic modifiers influence melanoma risk.
Familial Cancer 05/2009; 8(4):371-7. · 1.94 Impact Factor
[show abstract][hide abstract] ABSTRACT: To evaluate the contribution of MC1R variants to malignant melanoma risk in Israeli Jews, sequencing of the MC1R gene was performed in 132 melanoma patients and 184 ethnically matched controls. Overall, 22 MC1R variants were detected, two were novel (M73I and 496_497insG). Using age and sex-adjusted logistic regression, one specific variant, R151C, conferred significantly increased melanoma risk among Ashkenazim (OR=2.6, 95% CI: 1.3-5.3; p=0.05 after Bonferroni correction). A gene dosage effect was noted, with significantly increased melanoma risk being observed in subjects with at least two variants whether when all variants are pooled (OR=4.8, 95% CI: 2.0-11.2; p=0.002 after Bonferroni correction) or when red hair colour (RHC) variants and non-RHC variants are distinguished (OR=7.6, 95% CI: 2.8-20.3; p=0.0004 after Bonferroni correction). If further studies support these findings, the assessment of MC1R status may be useful in identifying Jewish Israeli individuals at high risk for melanoma.
European journal of cancer (Oxford, England: 1990) 04/2009; 45(11):2015-22. · 4.12 Impact Factor
[show abstract][hide abstract] ABSTRACT: The G101W founder mutation is the most common CDKN2A mutation in Italy, Spain, and France. As the background of modifying genes, environmental exposures, and sun behavior vary across countries, studying G101W carriers from distinct countries offers a unique opportunity to evaluate possible modifying factors in melanoma development. We evaluated 76 G101W cases and 59 carrier controls from France, Italy, Spain, and the United States. Hair color and dysplastic nevi distributions differed significantly in cases and controls across the 4 study groups. Cases also varied significantly for eye color, freckling, and nevi. The distribution of MC1R variants in cases differed significantly across study groups because 12% of Italian melanoma patients had > or =2 MC1R variants vs. >50% for the other case groups. Several MC1R covariates showed significant associations with melanoma risk in all groups combined and in the American, French, and Spanish samples; no significant findings were observed in the Italian sample. In multiple-case families, the number and type of MC1R variants varied significantly between multiple-primary-melanoma and single-primary-melanoma patients from the 4 groups; there was also a significant decrease in median age at melanoma diagnosis as the number or type of MC1R variants increased. The variation in the effects of the cutaneous phenotypic and MC1R factors across the study sample suggests that these factors differentially contribute to development of melanoma even on a common genetic background of a germline CDKN2A mutation. Differences in melanoma risk across geographic regions justify the need for individual studies in each country before counseling should be considered.
International Journal of Cancer 08/2007; 121(4):825-31. · 6.20 Impact Factor
[show abstract][hide abstract] ABSTRACT: The major factors individually reported to be associated with an increased frequency of CDKN2A mutations are increased number of patients with melanoma in a family, early age at melanoma diagnosis, and family members with multiple primary melanomas (MPM) or pancreatic cancer.
These four features were examined in 385 families with > or =3 patients with melanoma pooled by 17 GenoMEL groups, and these attributes were compared across continents.
Overall, 39% of families had CDKN2A mutations ranging from 20% (32/162) in Australia to 45% (29/65) in North America to 57% (89/157) in Europe. All four features in each group, except pancreatic cancer in Australia (p = 0.38), individually showed significant associations with CDKN2A mutations, but the effects varied widely across continents. Multivariate examination also showed different predictors of mutation risk across continents. In Australian families, > or =2 patients with MPM, median age at melanoma diagnosis < or =40 years and > or =6 patients with melanoma in a family jointly predicted the mutation risk. In European families, all four factors concurrently predicted the risk, but with less stringent criteria than in Australia. In North American families, only > or =1 patient with MPM and age at diagnosis < or =40 years simultaneously predicted the mutation risk.
The variation in CDKN2A mutations for the four features across continents is consistent with the lower melanoma incidence rates in Europe and higher rates of sporadic melanoma in Australia. The lack of a pancreatic cancer-CDKN2A mutation relationship in Australia probably reflects the divergent spectrum of mutations in families from Australia versus those from North America and Europe. GenoMEL is exploring candidate host, genetic and/or environmental risk factors to better understand the variation observed.
Journal of Medical Genetics 02/2007; 44(2):99-106. · 5.70 Impact Factor
[show abstract][hide abstract] ABSTRACT: Comprehensive analysis of the 9p21 locus including the CDKN2A, ARF, and CDKN2B genes in 53 individuals from melanoma index cases considered to be at heightened risk of melanoma.
Using a combination of DNA sequencing, gene copy number by real time quantitative PCR, linkage analysis, and transcript analysis in haploid somatic cell hybrids, we found no evidence for germline alteration in either coding or non-coding domains of CDKN2A and CDKN2B. However, we identified a p14ARF exon 1beta missense germline mutation (G16D) in a melanoma-neural system tumour syndrome (CMM+NST) family and a 8474 bp germline deletion from 196 bp upstream of p14ARF exon 1beta initiation codon to 11233 bp upstream of exon 1alpha of p16(INK4A) in a family with five melanoma cases. For three out of 10 families with at least three melanoma cases, the disease gene was unlinked to the 9p21 region, while linkage analysis was not fully conclusive for seven families.
These data reinforce the hypothesis that ARF is a melanoma susceptibility gene and suggest that germline deletions specifically affecting p14ARF may not be solely responsible for NST susceptibility. Predisposition to CMM+NST could either be due to complete disruption of the CDKN2A locus or be the result of more complex genetic inheritance. In addition, the absence of any genetic alteration in 50 melanoma prone families or patients suggests the presence of additional tumour suppressor genes possibly in the 9p21 region, and on other chromosomes.
Journal of Medical Genetics 02/2006; 43(1):39-47. · 5.70 Impact Factor
[show abstract][hide abstract] ABSTRACT: Germline mutations in CDKN2A gene predispose to melanoma with high but incomplete penetrance. Penetrance of CDKN2A gene was found to be significantly influenced by host factors (nevus phenotypes and sunburn) on one hand and by variants of MC1R gene (RHC variants consistently associated with red hair and fair skin) on the other hand. Our goal was to examine the joint effects of MC1R variants and other potential risk factors [total nevi, dysplastic nevi, pigmentary traits (skin, hair and eye color), skin reactions to sunlight, and degree of sun exposure] on CDKN2A penetrance. Clinical, genetic, and covariate data were recorded in 20 French melanoma-prone families with cosegregating CDKN2A mutations. Analysis of the cotransmission of melanoma and CDKN2A mutations was conducted by likelihood-based methods using the regressive logistic models, which can account for a variation of disease risk with age and can include the aforementioned risk factors as covariates. RHC variants, considered either alone or in the presence of pigmentation and nevus phenotypes, were found to increase significantly CDKN2A penetrance. Multivariate analysis, using a stepwise selection procedure, showed significant effects of two factors on melanoma risk in CDKN2A mutations carriers: RHC variants [odds ratio of hazard function (OR), 2.21; P = 0.03] and dysplastic nevi (OR, 2.93; P < 0.01). Such results may have important consequences to improve the prediction of melanoma risk in families.
[show abstract][hide abstract] ABSTRACT: Asthma is a complex disease, associated with biological and physiological phenotypes including immunoglobulin E (IgE) levels, sum of positive skin prick tests to allergens (SPTQ), eosinophil counts (EOS) and percent predicted forced expiratory volume in 1 s (%FEV1). We investigated the patterns of familial correlations and the inter-relationships of these four quantitative phenotypes, using the general class D regressive model, in 320 French EGEA nuclear families ascertained through 204 offspring (set A) and 116 parents (set B). Familial correlations of IgE and SPTQ were consistent with a model including no spouse correlation and equal parent-offspring and sib-sib correlations (rhoPO = rhoSS = 0.25 for IgE and 0.15 for SPTQ), this model being compatible with an additive polygenic model in the whole sample and the two family subsets A and B. Different patterns of familial correlations of EOS and %FEV1 were observed in these two sets. In set A, the best fitting model included no spouse correlation and equality of parent-offspring and sib-sib correlations (rhoPO = rhoSS = 0.14 for EOS and 0.23 for %FEV1). In set B, EOS had only a significant rhoSS of 0.28, while %FEV1 had significant rhoMO of 0.28 and rhoSS of 0.16. Analysis of shared familial determinants between these phenotypes indicated an overlap of at most 30% in rhoFO for IgE and SPTQ and in both rhoFO and rhoMO for IgE and EOS, while determinants of %FEV1 and atopy-related phenotypes appear distinct. These results may have implications for further linkage and association studies with genetic markers.
European Journal of HumanGenetics 12/2004; 12(11):955-63. · 4.32 Impact Factor
[show abstract][hide abstract] ABSTRACT: Few family studies have investigated the effects of genetic, environmental, and host factors on melanoma risk, and most have been restricted to high-risk families. We assessed the role of these factors on melanoma risk in two types of families: families ascertained through melanoma probands but unselected by family history and melanoma-prone families.
Data on pigmentary traits, nevus phenotypes, exposure to sun, and reactions to sunlight were collected from 295 families unselected by family history and 53 melanoma-prone families. We modeled melanoma risk using a logistic regressive model incorporating the effect of a melanoma-predisposing gene, familial dependence, and potential risk factors (e.g., pigmentary traits, nevus phenotypes, history of sun exposure, skin reactions to sunlight). Maximum-likelihood estimates of the parameters of the regressive model were used to compute odds ratios associated with each risk factor and age-specific melanoma risk depending on the genotype at the melanoma-predisposing gene and the effects of risk factors. All statistical tests were two-sided.
In the families unselected by family history, there was statistically significant evidence (P<.001) for a dominant gene, with melanoma risk reaching 0.49 and 0.67 by age 80 years in male and female gene carriers, respectively. Melanoma risk was statistically significantly influenced by total nevi (odds ratio of hazard function [OR] = 5.81, 95% confidence interval [CI] = 3.47 to 8.99), sun exposure (OR = 5.37, 95% CI = 4.44 to 6.36), and sunburn interacting with the gene (OR = 26.31, 95% CI = 7.56 to 99.22 in gene carriers and OR = 1.67, 95% CI = 1.36 to 2.03 in noncarriers). Twenty of the 53 melanoma-prone families had cosegregating mutations in CDKN2A, a gene known to be associated with melanoma. In these 53 families, three risk factors in addition to CDKN2A mutations increased melanoma risk: dysplastic nevi (OR = 2.32, 95% CI = 2.08 to 2.58), total nevi (OR = 1.99, 95% CI = 1.61 to 2.20) and sunburn (OR = 5.16, 95% CI = 4.82 to 5.52).
Together, a melanoma-predisposing gene (identified as being CDKN2A in melanoma-prone families), number of nevi and/or dysplastic nevi, and sun-related covariates influence melanoma risk in both families unselected by family history and melanoma-prone families.
[show abstract][hide abstract] ABSTRACT: Incidence of breast cancer (BC) varies among ethnic groups, with higher rates in white than in African-American women. Until now, most epidemiological and genetic studies have been carried out in white women. To investigate whether interactions between genetic and reproductive risk factors may explain part of the ethnic disparity in BC incidence, a genetic epidemiology study was conducted, between 1989 and 1994, at the Howard University Cancer Center (Washington, DC), which led to the recruitment of 245 African-American families. Segregation analysis of BC was performed by use of the class D regressive logistic model that allows for censored data to account for a variable age of onset of disease, as implemented in the REGRESS program. Segregation analysis of BC was consistent with a putative dominant gene effect (P < 0.000001) and residual sister-dependence (P < 0.0001). This putative gene was found to interact significantly with age at menarche (P = 0.048), and an interaction with a history of spontaneous abortions was suggested (P = 0.08). A late age at menarche increased BC risk in gene carriers but had a protective effect in non-gene carriers. A history of spontaneous abortions had a protective effect in gene carriers and increased BC risk in non-gene carriers. Our findings agree partially with a similar analysis of French families showing a significant gene x parity interaction and a suggestive gene x age at menarche interaction. Investigating gene x risk factor interactions in different populations may have important implications for further biological investigations and for BC risk assessment.
[show abstract][hide abstract] ABSTRACT: Parent-of-origin effects for atopy were investigated by a model-free affected sib-pair (ASP) method and two model-based approaches in the Busselton nuclear families. Among the regions showing potential linkages to atopy by the ASP method, a significant excess of paternal allele sharing as compared with maternal allele sharing was observed for a cluster of three markers on chromosome 13. The two model-based methods, which specify either sex-specific recombination rates or different penetrances for heterozygotes according to the parental origin of disease allele (imprinting), led to the same results, both suggesting a paternal effect. Thus, these two ways of modelling parent-of-origin effects appear equivalent in nuclear family data. Further simulations are needed to investigate whether the mechanisms underlying parent-of-origin effects can be distinguished in larger pedigree structures.