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Background: Most of large epidemiological studies on melanoma susceptibility have been conducted on fair skinned individuals (US, Australia and Northern Europe), while Southern European populations, characterized by high UV exposure and dark‐skinned individuals, are underrepresented. Objectives: We report a comprehensive pooled analysis of established high‐ and intermediate‐penetrance genetic variants and clinical characteristics of Mediterranean melanoma families from the MelaNostrum Consortium. Methods: Pooled epidemiological, clinical and genetic (CDKN2A, CDK4, ACD, BAP1, POT1, TERT, and TERF2IP and MC1R genes) retrospective data of melanoma families, collected within the MelaNostrum Consortium in Greece, Italy and Spain, were analysed. Univariate methods and multivariate logistic regression models were used to evaluate the association of variants with characteristics of families and of affected and unaffected family members. Subgroup analysis was performed for each country. Results: We included 839 families (1365 affected members and 2123 unaffected individuals). Pathogenic/likely pathogenic CDKN2A variants were identified in 13.8% of families. The strongest predictors of melanoma were ≥2 multiple primary melanoma cases (OR 8.1; 95% CI 3.3–19.7), >3 affected members (OR 2.6; 95% CI 1.3–5.2) and occurrence of pancreatic cancer (OR 4.8; 95% CI 2.4–9.4) in the family (AUC 0.76, 95% CI 0.71–0.82). We observed low frequency variants in POT1 (3.8%), TERF2IP (2.5%), ACD (0.8%) and BAP1 (0.3%). MC1R common variants (≥2 variants and ≥2 RHC variants) were associated with melanoma risk (OR 1.4; 95% CI 1.0–2.0 and OR 4.3; 95% CI 1.2–14.6, respectively). Conclusions: Variants in known high‐penetrance genes explain nearly 20% of melanoma familial aggregation in Mediterranean areas. CDKN2A melanoma predictors were identified with potential clinical relevance for cancer risk assessment. [ABSTRACT FROM AUTHOR]

Background: A polygenic inheritance involving high, medium and low penetrance genes has been suggested for melanoma susceptibility in adults, but genetic information is scarce for paediatric patients. Objective: We aim to analyse the major high and intermediate melanoma risk genes, CDKN2A, CDK4, POT1, MITF and MC1R, in a large multicentre cohort of Italian children and adolescents in order to explore the genetic context of paediatric melanoma and to reveal potential differences in heritability between children and adolescents. Methods: One‐hundred‐twenty‐three patients (<21 years) from nine Italian centres were analysed for the CDKN2A, CDK4, POT1, MITF, and MC1R melanoma predisposing genes. The rate of gene variants was compared between sporadic, familial and multiple melanoma patients and between children and adolescents, and their association with clinico‐pathological characteristics was evaluated. Results: Most patients carried MC1R variants (67%), while CDKN2A pathogenic variants were found in 9% of the cases, the MITF E318K in 2% of patients and none carried CDK4 or the POT1 S270N pathogenic variant. Sporadic melanoma patients significantly differed from familial and multiple cases for the young age at diagnosis, infrequent red hair colour, low number of nevi, low frequency of CDKN2A pathogenic variants and of the MC1R R160W variant. Melanoma in children (≤12 years) had more frequently spitzoid histotype, were located on the head/neck and upper limbs and had higher Breslow thickness. The MC1R V92M variant was more common in children than in adolescents. CDKN2A common polymorphisms and MC1R variants were associated with a high number of nevi. Conclusion: Our results confirm the scarce involvement of the major high‐risk susceptibility genes in paediatric melanoma and suggest the implication of MC1R gene variants especially in the children population. Linked Commentary: H. Helgadottir. J Eur Acad Dermatol Venereol 2022; 36: 167–168. https://doi.org/10.1111/jdv.17879. [ABSTRACT FROM AUTHOR]

Trichilemmal cysts (TCs) can occur as sporadic lesions or in hereditary-familial settings with autosomal dominant transmission. These entities have not been widely analyzed in their peculiar aspects yet. The aim of this study was to describe a cohort of patients with diagnosis of TCs through a clinical and biomolecular characterization, intended to highlight some effective diagnostic criteria for their identification. Among 149 cases of this study, 24 cases of TCs (16.1%) arose in patients with at least one first-degree relative with diagnosis of TCs. Peculiar findings concerning hereditary lesions included the multiple presentation with an early onset age. On the basis of clinical evaluation, we propose a panel of clinical and histologic criteria for the diagnosis of hereditary TCs, which includes: (i) the diagnosis of TCs in at least two first-degree relatives or in three first- or second-degree relatives in two consecutive generations; (ii) at least one of the patients with TCs diagnosed <45 years; and (iii) the diagnosis of multiple or giant (>5-cm lesions) or rare histopathologic features (proliferating and ossifying) TCs. [ABSTRACT FROM AUTHOR]

A French and an Australian study have recently identified a rare germline functional variant in the microphthalmia-associated transcription factor ( MITF) ( E318 K) that predisposes to familial and sporadic melanoma and to renal cell carcinoma ( RCC), showing a new link between two tumour types with different risk factors and between deregulated sumoylation and cancer. The aim of this study was to test the prevalence of the MITF E318 K mutation in 667 Italian melanoma patients. We observed significant associations between histological subtypes and family cancer history. Carriers exhibited a nearly threefold higher risk of developing melanoma compared with controls. Carriers were also more likely to have developed multiple primary melanomas (6.40-fold), compared with wt patients. Carriers with a personal and/or family history of pancreatic cancer and kidney cancer had a nearly 31- and eightfold higher risk of developing melanoma compared with wt patients. Our findings further support MITF as a medium-penetrance melanoma susceptibility gene, highlight a potential association with histological subtypes and suggest that MITF may predispose to pancreatic cancer. [ABSTRACT FROM AUTHOR]

The article discusses a report on the first molecular analysis of six consenting Italian patients with histologically confirmed multiple cylindromas. It is stated that the researchers identified five novel germline CYLD mutations. It mentions that The Brooke-Spiegler syndrome is an autosomal dominant disorder with variable penetrance.

We evaluated the contribution of germline CDKN2A mutations and MC1R variants to the development of melanoma in a hospital-based study of single (SPM, n = 398) and multiple primary melanoma (MPM, n = 95). The overall frequency of CDKN2A mutations was 15.2%, and four-fold higher in MPM than in SPM cases (OR = 4.27; 95% CI 2.43–7.53). The likelihood of identifying a CDKN2A mutation increased with family history of melanoma and younger age at diagnosis in MPM cases. Compared to SPM patients, the risk of harboring a CDKN2A mutation rose as the number of primary melanomas increased and was not influenced by family history. The G101W and E27X founder mutations were the most common. Several other mutations (W15X, Q50X, R58X, A68L, A127P and H142R) were detected for the first time in Italian patients. One novel mutation, T77A, was identified. Several non-coding variants with unknown functional significance were also found (5′UTR −25C > T, −21C > T, −67G > C, IVS1 +37G > C); the novel 5′UTR −21C > T variant was not detected in controls. The CDKN2A A148T polymorphism was more frequent in MPM patients than in the control population (15.7% versus 6.6%). Compared to the SPM patients, MPM cases had a 2-fold increased probability of being MC1R variant carriers and a higher probability of carrying two or more variants. No specific association was observed between the type of variant and the number of melanomas, suggesting that the number rather than the type of MC1R variant increases the risk of MPM. We observed no interaction between CDKN2A status and the presence of MC1R variants. The high frequency of CDKN2A mutations in our MPM cases, independent of their family history, is of relevance to genetic counseling and testing in our population. [ABSTRACT FROM AUTHOR]

Diagnosis of Nevoid Basal Cell Carcinoma Syndrome (NBCCS) in infants may pose significant challenges to clinicians owing to its variable expressivity and age-related manifestations.We report two paediatric cases of NBCCS who presented initially with a non-specific phenotype.In case 1, a diagnosis of NBCCS was possible only after the father was interviewed and found to present with two major criteria for the disease. Subsequent molecular testing confirmed the diagnosis. In case 2, molecular testing of the infant and his father had diagnostic value as neither satisfied fully the current diagnostic criteria for NBCCS.Presence of the few clinical manifestations of NBCCS that appear in infants, typically congenital malformations and skeletal abnormalities, should prompt clinicians to conduct in-person interviews with both parents. In general, paediatricians should refer both parents of infants who are suspected of having an inherited condition to clinical geneticists for expert examination, given the potential unreliability of reported medical history. [ABSTRACT FROM AUTHOR]

Abstract We have tested whether different agonists of metabotropic glutamate receptors could induce translocation of selective protein kinase C isozymes in nerve terminals. In rat cortical synaptosomes 1S,3R-1-aminocyclopentane-1,3-dicarboxylic acid (1S,3R-ACPD; 100 μm) induced an increase in translocation to 124.6 ± 5.7% of basal unstimulated conditions of the Ca++-independent protein kinase Cε, but not of the Ca++-dependent isozyme β. This effect was counteracted by 1-aminoindan-1,5-dicarboxylic acid (100 μm), an antagonist of metabotropic glutamate receptor 1. On the other hand, (+)-α-methyl-4-carboxyphenylglycine [(+)-MCPG], an antagonist of metabotropic glutamate receptors group I and II, did not antagonize the effect of 1S,3R-ACPD, and per se induced a translocation of protein kinase Cε of 164 ± 17.7% of basal unstimulated conditions. Because the (+)-MCPG induction of protein kinase Cε translocation was not antagonized by 1-aminoindan-1,5-dicarboxylic acid, it is suggested that 1S,3R-ACPD and (+)-MCPG activate this signal transduction pathway through distinct membrane receptors. Indeed (2-[2′′-carboxy-3′-phenylcyclopropyl]glycine)-13 (300 nm), a new compound known to antagonize metabotropic glutamate receptors coupled to phospholipase D, was able to antagonize protein kinase Cε translocation induced by (+)-MCPG. Moreover (+)-MCPG directly induced phospholipase D activity, measured as [3H]phosphoethanol production in cortical synaptosomes. These data suggest that in cortical nerve terminals (i) distinct metabotropic glutamate receptors, coupled to different signal transduction pathways, are present, (ii) (+)-MCPG is able to induce protein kinase Cε translocation, and that (iii) a metabotropic glutamate receptor associated to phospholipase D might influence translocation of protein kinase C in a calcium-independent manner. [ABSTRACT FROM AUTHOR]

Abstract The calcium-calmodulin-dependent protein kinase II (CaMKII) subserves activity-dependent plasticity in central neurons. To examine in vivo the implication of CaMKII activity in synaptic plasticity, we used an animal model characterized by developmentally induced targeted neuronal ablation within the cortex and the hippocampus, and showing, at presynaptic level, molecular alterations leading to facilitation of glutamate release in hippocampal synapses (methylazoxymethanol-treated rats, MAM-rats). We report here that at the postsynaptic side, the activity of CaMKII is markedly decreased in MAM-rats when compared to controls, although the concentration of the enzyme in Post Synaptic Density (PSD) is not altered. This effect is confined to PSD-associated CaMKII, as enzyme activity tested in the soluble fraction is unchanged in MAM-rats. In addition, the decreased activity is not due to inhibition by autophosphorylation in specific sites within the calmodulin-binding domain, as preincubation with purified phosphatases 1 and 2A failed to restore CaMKII activity in PSD of MAM-rats. The CaMKII-dependent phosphorylation of NR2A/B subunits of NMDA receptor is lower in MAM-rats when compared to controls (51.77 ± 7.39% of controls level), as revealed in back-phosphorylation experiments. In addition, a treatment able to restore long-term potentiation (LTP) in hippocampal slices from MAM-rats, e.g. exposure to d-serine, is able to restore CaMKII activity to the control value. [ABSTRACT FROM AUTHOR]

Mutations in the PTCH gene, the human homolog of the Drosophila patched gene, have been found to lead to the autosomal dominant disorder termed Nevoid Basal Cell Carcinoma Syndrome (NBCCS, also called Gorlin Syndrome). Patients display an array of developmental anomalies and are prone to develop a variety of tumors, with multiple Basal Cell Carcinomas occurring frequently. We provide here the results of molecular testing of a set of Italian Nevoid Basal Cell Carcinoma Syndrome patients. Twelve familial patients belonging to 7 kindreds and 5 unaffected family members, 6 non-familial patients and an additional set of 7 patients with multiple Basal Cell Carcinoma but no other criteria for the disease were examined for mutations in the PTCH gene. All of the Nevoid Basal Cell Carcinoma Syndrome patients were found to carry variants of the PTCH gene. We detected nine novel mutations (1 of which occurring twice): 1 missense mutation (c.1436T>G [p.L479R]), 1 nonsense mutation (c.1138G>T [p.E380X]), 6 frameshift mutations (c.323_324ins2, c.2011_2012dup, c.2535_2536dup, c.2577_2583del, c.3000_3005del, c.3050_3051del), 1 novel splicing variant (c.6552A>T) and 3 mutations that have been previously reported (c.3168+5G>A, c.1526G>T [p.G509V], and c.3499G>A [p.G1167R]). None of the patients with multiple Basal Cell Carcinoma but no other criteria for the syndrome, carried germline coding region mutations. © 2005 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Gorlin syndrome (GS) is inherited in an autosomal dominant pattern with high-penetrance and is characterized by a range of developmental anomalies and increased risk of developing basal cell carcinoma and medulloblastoma. Between 50% and 85% of patients with GS harbor germ line mutations in the only susceptibility gene identified to date, PTCH1, a key component in the Sonic Hedgehog signaling pathway. Another component in this pathway, SUFU, is known to be involved in susceptibility to medulloblastoma but has never been reported in GS patients to date. We have identified the known c.1022 + 1G>A SUFU germ line splicing mutation in a family that was PTCH1-negative and who had signs and symptoms of GS, including medulloblastoma. This is the first report of a germ line SUFU mutation associated with GS.