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Oncogenic mutations in the EGFR gene are targets of tyrosine kinase inhibitors (TKIs) in lung adenocarcinoma (LC) patients, and their search is mandatory to make decisions on treatment strategies. Liquid biopsy of circulating tumour DNA (ctDNA) is increasingly used to detect EGFR mutations, including main activating alterations (exon 19 deletions and exon 21 L858R mutation) and T790M mutation, which is the most common mechanism of acquired resistance to first- and second-generation TKIs. In this study, we prospectively compared three different techniques for EGFR mutation detection in liquid biopsies of such patients. Fifty-four ctDNA samples from 48 consecutive advanced LC patients treated with TKIs were tested for relevant EGFR mutations with Therascreen® EGFR Plasma RGQ-PCR Kit (Qiagen). Samples were subsequently tested with two different technologies, with the aim to compare the EGFR detection rates: real-time PCR based Idylla™ ctEGFR mutation assay (Biocartis) and next-generation sequencing (NGS) system with Ion AmpliSeq Cancer Hotspot panel (ThermoFisher). A high concordance rate for main druggable EGFR alterations was observed with the two real-time PCR-based assays, ranging from 100% for T790M mutation to 94% for L858R variant and 85% for exon 19 deletions. Conversely, lower concordance rates were found between real-time PCR approaches and the NGS method (L858R: 88%; exon19-dels: 74%; T790M: 37.5%). Our results evidenced an equivalent detection ability between PCR-based techniques for circulating EGFR mutations. The NGS assay allowed detection of a wider range of EGFR mutations but showed a poor ability to detect T790M.

Supplemental Digital Content is available in the text., Gastrointestinal stromal tumor (GIST) is the most common mesenchymal malignancy of the gastrointestinal tract. We provide in the present article the molecular characterization of a series of primary GISTs in a cohort of Sardinian patients (Italy), with the aim to describe the patterns of KIT and PDGFRa mutations and the corresponding clinical features. Ninety-nine Sardinian patients with histologically-proven diagnosis of GIST were included in the study. Medical records and pathology reports were used to assess the demographic and clinical features of the patients and the disease at the time of the diagnosis. Formalin-fixed, paraffin-embedded tissue samples were retrieved for each case, and mutation analysis of the KIT and PDGFRa genes was performed. KIT and PDGFRa mutations were detected in 81.8% and 5% of the cases, respectively. The most common KIT mutation was W557_K558del in exon 11, while D842V in exon 18 was the most common PDGFRa genetic alteration; V561D was the only PDGFRa mutation found in exon 12. The global “wild-type” cases, with no mutations in either the KIT or PDGFRa genes, were 13 (13.1%). The mean survival of those patients was approximately 46.9 (±43.9) months. Globally, 86.9% of Sardinian patients with GIST had a KIT or PDGFRa mutation; the former were more frequent in comparison with other Italian cohorts, while PDGFRa mutations were rare. No statistical differences in survival between mutated and wild-type cases, and between KIT and PDGFRa mutated cases were detected in our study.

Background Advanced lung adenocarcinoma (LAC) is one of the most lethal malignancies worldwide. The aim of this study was to evaluate the global survival in a real-life cohort of patients with LAC harboring driver genetic alterations. Methods A series of 1282 consecutive Sardinian LAC patients who underwent genetic testing from January 2011 through July 2016 was collected. Molecular tests were based on the clinical needs of each single case (EGFR-exon18/19/21, ALK, and, more recently, BRAF-exon15), and the availability of tissue (KRAS, MET, and presence of low-frequency EGFR-T790M mutated alleles at baseline). Results The mean follow-up time of the patients was 46 months. EGFR, KRAS, and BRAF mutations were detected in 13.7%, 21.3%, and 3% of tested cases, respectively; ALK rearrangements and MET amplifications were found respectively in 4.7% and 2% of tested cases. As expected, cases with mutations in exons 18–21 of EGFR, sensitizing to anti-EGFR tyrosine kinase inhibitors (TKIs) agents, had a significantly longer survival in comparison to those without (p

The improvement of the immunotherapeutic potential in most human cancers, including melanoma, requires the identification of increasingly detailed molecular features underlying the tumor immune responsiveness and acting as disease-associated biomarkers. In recent past years, the complexity of the immune landscape in cancer tissues is being steadily unveiled with a progressive better understanding of the plethora of actors playing in such a scenario, resulting in histopathology diversification, distinct molecular subtypes, and biological heterogeneity. Actually, it is widely recognized that the intracellular patterns of alterations in driver genes and loci may also concur to interfere with the homeostasis of the tumor microenvironment components, deeply affecting the immune response against the tumor. Among others, the different events linked to genetic instability—aneuploidy/somatic copy number alteration (SCNA) or microsatellite instability (MSI)—may exhibit opposite behaviors in terms of immune exclusion or responsiveness. In this review, we focused on both prevalence and impact of such different types of genetic instability in melanoma in order to evaluate whether their use as biomarkers in an integrated analysis of the molecular profile of such a malignancy may allow defining any potential predictive value for response/resistance to immunotherapy.

The development and progression of melanoma, like that of all other malignancies, are based on the progressive acquisition of alterations affecting specific genes and pathways regulating melanocytic cell functions. Such molecular changes are determining the biological and clinical behavior of the disease, in terms of pathogenesis, prognosis, and propensity or resistance to therapeutic responses. As consequence, a detailed classification of the intrinsic intratumor heterogeneity of melanoma may identify patients with different molecular subtypes. The aim of the present review is to provide an update about all current advancements toward the definition of the main molecular profiles associated with tumor cell proliferation, invasion, survival, and migration underlying the different clinical phenotypes in patients with melanoma. In this sense, next-generation sequencing (NGS) approaches are extremely useful in unveiling the mutation landscapes in driver genes and pathways. Putting together all recent data, the melanoma pathogenesis scenario appears to be highly more complicated than hypothesized before. A molecular classification strategy based on such in-depth knowledge is becoming mandatory in order to discriminate melanoma patients for their clinical behavior and outcome. In other words, a more extensive molecular classification will increasingly be an integral part of the management of patients with melanoma.

Simple Summary The recent WHO classification of melanocytic tumors requires the implementation of combined phenotypic–genotypic diagnostics. For rare tumors, such as atypical deep penetrating nevi, there is insufficient information regarding genetic status, and it is not yet clear whether the observed unusual morphological cyto-architectures reflect a distinct genomic profile or are associated with an increased metastatic potential and aggressive clinical behavior. We report herein a comprehensive next-generation sequencing (NGS) analysis of a series of atypical DPNs, showing their mutational profile with some specific signatures for these rare and diagnostically challenging tumors. Abstract Deep penetrating nevi (DPNs) are rare melanocytic neoplasms consisting of pigmented spindled or epithelioid melanocytes with a distinctive wedge-shaped configuration showing activation of the WNT pathway, with unusual cyto-architectural features. It is unclear whether they show a distinct genomic profile associated with a diverse metastatic potential. We describe herein a cohort of 21 atypical DPNs analyzed by next-generation sequencing using the Ion AmpliSeq™ Comprehensive Cancer Panel. We found that β-catenin exon 3 was mutated in 95% and MAP kinase pathway genes in 71% of the cases. Less frequent mutations were observed in HRAS (19%) and MAP2K1 (24%). Isocitrate dehydrogenases 1 (IDH1) mutations, including R132C, V178I, and S278L, were identified in 38% of cases and co-existed with BRAF/HRAS mutations. The only case with progressive nodal disease carried alterations in the β-catenin pathway and mutations in IDH1 and NRAS (codon 61). By a comprehensive mutation analysis, we found low genetic heterogeneity and a lack of significant associations between specific gene mutations and histopathological features, despite atypical features. Whether the acquisition of an NRAS or IDH1 mutation in an atypical DPN may represent a molecular evolution implying a pathway to melanoma progression should be confirmed in a larger series.

Malignant melanoma (MM) is one of the deadliest skin cancers. BRAF mutation status plays a predominant role in the management of MM patients. The aim of this study was to compare BRAF mutational testing performed by conventional nucleotide sequencing approaches with either real-time polymerase chain reaction (rtPCR) or next-generation sequencing (NGS) assays in a real-life, hospital-based series of advanced MM patients. Consecutive patients with AJCC (American Joint Committee on Cancer) stage IIIC and IV MM from Sardinia, Italy, who were referred for molecular testing, were enrolled into the study. Initial screening was performed to assess the mutational status of the BRAF and NRAS genes, using the conventional methodologies recognized by the nationwide guidelines, at the time of the molecular classification, required by clinicians: at the beginning, Sanger-based sequencing (SS) and, after, pyrosequencing. The present study was then focused on BRAF mutation detecting approaches only. BRAF wild-type cases with available tissue and adequate DNA were further tested with rtPCR (Idylla™) and NGS assays. Globally, 319 patients were included in the study; pathogenic BRAF mutations were found in 144 (45.1%) cases examined with initial screening. The rtPCR detected 11 (16.2%) and 3 (4.8%) additional BRAF mutations after SS and pyrosequencing, respectively. NGS detected one additional BRAF-mutated case (2.1%) among 48 wild-type cases previously tested with pyrosequencing and rtPCR. Our study evidenced that rtPCR and NGS were able to detect additional BRAF mutant cases in comparison with conventional sequencing methods; therefore, we argue for the preferential utilization of the aforementioned assays (NGS and rtPCR) in clinical practice, to eradicate false-negative cases and improve the accuracy of BRAF detection.

Il carcinoma cutaneo a cellule squamose è il secondo tumore della pelle per incidenza, ma ancora poco conosciuto. L'A.I.Ma.Me (Associazione Italiana Malati di Melanoma e Tumori della Pelle), a partire dal 2019, ha dato vita a un Gruppo di lavoro specifico sul Carcinoma Cutaneo a Cellule Squamose (CSCC) e, per sensibilizzare tutti i cittadini sulle regole di prevenzione e dar voce ai pazienti, ha realizzato il Libro Bianco su questa patologia. Il presente capitolo introduttivo affronta le caratteristiche di questo tumore partendo dalla descrizione delle caratteristiche dei tumori cutanei: melanoma e tumori non-melanoma. Vengono poi descritte le caratteristiche del CSCC, le modalità di sviluppo, i fattori di rischio, i sottotipi istologici del CSCC, i fattori prognostici per recidiva/avanzamento di malattia. I meccanismi molecolari alla base del CSCC sono scarsamente chiariti e i driver della progressione della malattia non sono stati completamente definiti e vengono prese inconsiderazione le attuali conoscenze in questo campo.

Our group is long evaluating epidemiological and genetic features of breast-ovarian cancers and other BRCA-related tumor in North Sardinia, Italy. Individuals carrying a predisposing mutation in one or both of the BRCA (BRCA1 or BRCA2) genes have a significantly increased risk of developing breast/ovarian cancer (BOC) and other BRCA-related tumors such as pancreatic and prostate cancer. Epidemiological data on incidence and distribution of such cancers are obtained from the local tumor registry; 411 genetic testing for BRCA gene mutations have been performed. Germline NGS-based analysis were performed in all young breast cancer patients or all women (over 50 years) with a strong family history of BOC (total of 384 cases), males with sporadic breast cancer (6 cases) and one with prostate cancer, and lately patients with pancreatic cancer (20 cases). Genetic testing for breast and ovarian cancer has clinical importance for identification of potentially affected families and for cancer prevention. Approximately, 5-10% of breast and ovarian cancer are familiar while about 90% are sporadic tumor cases. BRCA germline mutations account for approximately 10-15% of BOC cancers. Confirming previous results from our group, a higher prevalence of the BRCA2 mutation was observed in North Sardinia as compared to the general population and highlight the presence of specific germline mutation associated with the "founder effect" in distinct genetic subgroups reflecting genetic drift. Conversely, BRCA1 mutations are much more strongly associated at higher rates of BOC cancer in South Sardinia. Heterozygous BRCA mutations determine loss of function of the remaining wild-type allele, resulting in deficient homologous recombination DNA repair, which causes genetic aberrations that drive carcinogenesis. PARP inhibition in mutated tumor cells with deficient homologous-recombination repair generates unrepaired DNA single-strand breaks that are likely to cause the accumulation of DNA double-strand breaks and collapsed replication forks. Currently, analysis performed on somatic tissue allows to identify a greater number of mutations in BRCA-related tumor (additional 5-7% of cases as compared to germline testing). As consequence, the current mutational analysis is based on the use of multigenic NGS customized "Oncomine Cancer panels" that allow to analyze additional genes involved in the onset of cancer (SMAD4, ATM, CHEK2, APC, NF, KRAS, CDKN2A) as well as in maintaining the genome integrity (POLE, PALB2, PTEN, TP53, PIK3CA). Notably, detection of three PIK3CA hot spot mutations - E545K, E542K, H1047R (detected in about 40% cases) - is a new targeted therapy with PIK3CA inhibitors and represent a new strategy to overcome resistance in mutated advanced breast cancer. Analogously, combination of PARP and AR (androgen receptor) inhibitors was demonstrated to exert a benefit into the treatment of prostate cancer. The androgen receptor promotes DNA damage repair and upregulates PARP-mediated repair pathways, thus increasing the effectiveness of the PARP inhibitor. Finally, in pancreatic adenocarcinoma, the presence of mutations in cancer susceptibility genes and the involvement of external factors (such as those underlying local inflammation) play a role in pathogenesis along with the occurrence of somatic mutation in KRAS and other "driver" genes (SMAD4 and CDKN2A), leading to the use of new targeted therapies.

Idiopathic Pulmonary Fibrosis (IPF) is a specific, chronic and progressive form of interstitial pneumonia with sever prognosis and poor survival rates (2/3 years from diagnosis). IPF incidence is estimated in 2/30 cases per 100.000 persons/years, mainly affecting over 65 years old individuals. Although pathophysiological mechanisms are not fully understood, environmental and occupational factors, smoking, viral infections, and traction injury of the lung are recognized as causative elements leading to chronic damage to the alveolar epithelium. IPF is considered an epithelium-driven disease where recurring micro-injuries in lung epithelia promote an imbalance between profibrotic (TGF-?, PDGF, bFGF, IL-1, TNF-?) and anti-fibrotic (KGF, HGF, EPC) mediators. In this scenario, chronic fibrosis replaces normal repair mechanisms: excessive fibroblasts proliferation and aberrant extracellular matrix remodeling determine an irreversible distortion of lungs architecture and subsequent evolution in honeycombing areas. IPF shares several molecular, pathophysiological and clinical aspects with lung cancer, including high mortality rates; in particular, both diseases share genetic and epigenetic factors, enhanced proliferation and abnormal activation of specific signaling transduction pathways. The prevalence of lung cancer, particularly adenocarcinoma, in patients with IPF in clinical studies ranges from 31% in older reports to 10-17% in more recent reports. Nevertheless, these figures were consistently lower in epidemiological studies, ranging from 4% to 7%. IPF patients affected by lung cancer are commonly male, smokers or ex-smokers, at their 6th or 7th decade of life; lung cancer arises generally 2-3 years after the diagnosis of IPF, and affects mostly the peripheral aspect of the lower lobes of the lungs where fibrosis is more frequent and consistent Considering the above-mentioned similarities, we started a comparative study of the mutational landscape in IPF and lung cancer tissue biopsies. We have already collected formalin-fixed, paraffin embedded (FFPE) IPF tissues samples (28 cases over 49 recorded in our database), 15% of which has progressed to lung cancer (IPF/K). In addition, we aim to carry out further comparisons using as a reference sample a previously analyzed cohort of IPF-unrelated lung adenocarcinomas. Our study is structured in 3 steps: a) clinical and pathological data collection: comorbidity, lifestyle (e.g. smokers/non-smokers), respiratory parameters (PFT, FEV, FVC, TLC, DLCO, BPCO, chronic respiratory failure degree and pulmonary hypertension); b) histopathologic classification and centralized FFPE sections processing; c) DNA and RNA extraction from FFPE followed by NGS mutational analysis using a multi-genic panel (52 main oncogenes and tumor suppressor genes involved in tumorigenesis). Our preliminary results on 28 DNA/RNA from FFPE IPF tissue biopsies, we found 16 missense variants spreading on 11 genes. Among them, 3 are filtered out as pathogenic by prediction algorithms in FGFR3, MTOR and PIK3CA genes respectively, that play a pivotal role in cellular growth and proliferation mechanisms. Once completed the mutational analyses in all collected samples (IPF and IPF/K), we plan to evaluate correlation between different molecular profiles and clinical-pathological parameters in order to define potential patients subgroups. Furthermore, all results will be compared with the reference sample of lung adenocarcinoma previously processed using the the same panel. Defining consistent patients sub-groups is indeed crucial for better understanding the molecular mechanisms underlying the IPF pathogenesis and its progression to lung cancer.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive human pancreatic cancer type accounting for about 90% of all malignant pancreatic neoplasms. It represents the fourth leading cause of cancer death in the Western World, projected to become the second cause by 2030. In our country, the PDAC incidence is about 14,000 new cases per year and represents 3% of all cancer cases (AIRTUM 2019), equally distributed between the sexes. Up to 15-20% of patients are eligible for resection at diagnosis. The 5 years overall survival for PDAC patients is around 8%; even for patients eligible for resection, the 5 years survival is no more than 15-20%. At least 25% of pancreatic cancers harbor "actionable" molecular alterations, defined as molecular alterations for which there is clinical evidence of a predictive benefit from a specific therapy (targeted therapy). We started a study by Next Generation Sequencing (NGS) analysis in primitive and metastatic PDAC tissues from the same patients, to define the molecular alterations pattern underlying neoplastic progression in pancreatic cancer. Tumor samples - 50 primitive PDAC cases and 50 related lymph node metastases - have been selected from archived formalin-fixed and paraffin-embedded (FFPE) samples, of which clinical-pathological data are available. To date have been analyzed 11 samples (4 primitive/metastasis matched cases and 3 primitive tumors) by NGS screening using "Oncomine Tumor specific panel", including main genes involved in onset and progression of PDAC (KRAS, CDKN2A, SMAD4, CHEK2, APC, NF1), in genome damage repair (POLE, PALB2, PTEN, TP53), and in mismatch repair mechanism (MLH1, MSH2.MSH3, MSH6). Preliminary data of mutational analysis are shown in the following Tables. The main endpoint for the analysis of all of cases is to identify mutational patterns to relate to clinical-pathological parameters of PDAC, as a starting point for finding novel tumor biomarkers associated with the disease.

Sinonasal mucosal melanoma (SNM) is a rare and aggressive type of melanoma, and because of this, we currently have a limited understanding of its genetic and molecular constitution. The incidence among SNMs of somatic mutations in the genes involved in the main molecular pathways, which have been largely associated with cutaneous melanoma, is not yet fully understood. Through a next-generation sequencing (NGS) approach using a panel of 25 genes involved in melanoma pathogenesis customized by our group, we performed a mutation analysis in a cohort of 25 SNM patients. Results showed that pathogenic mutations were found in more than 60% of SNM cases at a somatic level, with strikingly 32% of them carrying deleterious mutations in the BRAF gene. The identified mutations mostly lack the typical UV signature associated with cutaneous melanomas and showed no significant association with any histopathological parameter. Oncogenic activation of the BRAF-depending pathway, which may induce immune tolerance into the tumour microenvironment (i.e., by increasing the VEGF production) was poorly associated with mutations in genes that have been related to diminished clinical benefit of the treatment with BRAF inhibitors. Screening for mutations in BRAF and other MAPK genes should be included in the routine diagnostic test for a better classification of SNM patients.

In the present study, the phenotype of melanoma cells resistant to dabrafenib (a B-RAF inhibitor) was investigated, to shed more light on melanoma resistance to B-RAF inhibition. Melanoma cells resistant to dabrafenib were generated using 3 different cell lines, A375, 397 and 624.38, all carrying B-RAFV600E, and they were characterized by cytofluorometric analysis, Ion Torrent technology, immunofluorescence and biochemistry. All dabrafenib-resistant cells showed, in addition to a re-activation of MAPK signaling, morphological changes compared to their sensitive counterparts, accompanied by an increase in CD90 (mesenchymal marker) expression and a decrease in E-cadherin (epithelial marker) expression, suggesting an epithelial-to-mesenchymal-like phenotypic transition. However, melanoma cells with TGF-β1-induced epithelial-to-mesenchymal transition (EMT) were more sensitive to dabrafenib treatment compared to the sensitivity noted in the non-TGF‑β1‑induced EMT melanoma cells, suggesting that TGF-β1-induced EMT was not associated with dabrafenib resistance. Although dabrafenib-resistant cells exhibited increased cell motility and E-cadherin/vimentin reorganization, as expected in EMT, all of them showed unvaried E-cadherin mRNA and unchanged Snail protein levels, while Twist1 protein expression was decreased with the exception of A375 dabrafenib-resistant melanoma cells, where it was unaffected. These findings suggest a distinct active EMT-like process adopted by melanoma cells under drug exposure. Furthermore, dabrafenib-resistant cells exhibited stem cell-like features, with Oct4 translocation from the cytoplasm to peri-nuclear sites and nuclei, and increased CD20 expression. In conclusion, our data, in addition to confirming that resistance to dabrafenib is dependent on re-activation of MAPK signaling, suggest that this resistance is linked to a distinct active EMT-like process as well as stem-cell features adopted by melanoma cells.

The Tubulin Based Polymorphism (TBP) method was used to genotype olive cultivars of different origin and to produce short-size cultivar-specific molecular probes. Both the first and the second intron of the members of the olive β-tubulin gene family were exploited as sources of DNA polymorphism. Compared with the data obtained with the use of a set of 11 SSR markers selected from an Olea europea L. database, TBP is shown to provide similar, if not better, information about the polymorphic content of the olive genomes, releasing, at the same time, a simple and discriminatory DNA barcode specific for any of the analyzed cultivars. Such a barcode is the source for the preparation of variety specific molecular probes.

High frequency of mutations seems to determine a higher occurrence of neoepitope formation and, thus, tumor immunogenicity. A somatic hypermutated status could thus act as a predictive biomarker of responsiveness to immunotherapy with recent immune checkpoint inhibitors. Among several factors involved in determining the hypermutated status, such as inactivating mutations in the DNA polymerases as well as exposure to external (cigarette smoke, UV radiation, chemicals) and endogenous (reactive oxygen species) mutagens, a defective DNA mismatch repair system may give rise to genetic instability and, particularly, to microsatellite instability (MSI). The occurrence of MSI has been associated with increased load of mutations and expression of abundant peptides that serve as neoantigens to elicit an immune response within a context of a favorable tumor microenvironment. Here we describe methodological strategies to investigate for the presence of the MSI phenotype in cancer samples, through a combination of molecular approaches performed on paraffin-embedded tissues.

High frequency of mutations seems to determine a higher occurrence of neoepitope formation and, thus, tumor immunogenicity. A somatic hypermutated status could thus act as a predictive biomarker of responsiveness to immunotherapy with recent immune checkpoint inhibitors. Among several factors involved in determining the hypermutated status, such as inactivating mutations in the DNA polymerases as well as exposure to external (cigarette smoke, UV radiation, chemicals) and endogenous (reactive oxygen species) mutagens, a defective DNA mismatch repair system may give rise to genetic instability and, particularly, to microsatellite instability (MSI). The occurrence of MSI has been associated with increased load of mutations and expression of abundant peptides that serve as neoantigens to elicit an immune response within a context of a favorable tumor microenvironment. Here we describe methodological strategies to investigate for the presence of the MSI phenotype in cancer samples, through a combination of molecular approaches performed on paraffin-embedded tissues.

SUMMARY Among human cancers, melanoma remains one of the malignancies with an ever-growing incidence in white populations. Recent advances in biological and immunological therapeutic approaches as well as increased efforts for secondary prevention are contributing to improve the survival rates. It is likely that a significant fall in mortality rates for melanoma will be achieved by further increase of the early detection through a more accurate selection of the higher-risk individuals (i.e., carriers of predisposing genetic alterations). A similar scenario occurs in Italy. In the present review, we have considered data on incidence, survival and mortality rates of melanoma in Italian population, including evaluation of the main risk factors and genetic mutations underlying disease susceptibility.

Purpose of Review Conventional clinico-pathological features in melanoma patients should be integrated with new molecular diagnostic, predictive, and prognostic factors coming from the expanding genomic profiles. Cutaneous melanoma (CM), even differing in biological behavior according to sun-exposure levels on the skin areas where it arises, is molecularly heterogeneous. The next-generation sequencing (NGS) approaches are providing data on mutation landscapes in driver genes that may account for distinct pathogenetic mechanisms and pathways. The purpose was to group and classify all somatic driver mutations observed in the main NGS-based studies. Recent Findings Whole exome and whole genome sequencing approaches have provided data on spectrum and distribution of genetic and genomic alterations as well as allowed to discover new cancer genes underlying CM pathogenesis. Summary After evaluating the mutational status in a cohort of 686 CM cases from the most representative NGS studies, three molecular CM subtypes were proposed: BRAFmut , RASmut , and non-BRAFmut /non-RASmut .

Background: Cutaneous melanoma is one of the most frequent malignancies of the skin in Caucasian populations. Patients who develop cutaneous melanoma are at increased risk of developing a second primary melanoma. The estimated incidence of multiple primary melanoma (MPM) ranges from 1.2% to 8.2% of cases, with a high preponderance of melanomas occurring metachronously. Objectives: The aim of this study was to describe dermoscopic, microscopic, clinical, and molecular correlations between first and subsequent melanomas in patients with metachronous MPMs. Materials & methods: Twenty-four paired melanomas from 12 MPM patients were evaluated for architectural characteristics based on dermoscopy and confocal microscopy, as well as for mutations in BRAF and NRAS genes by Sanger-based sequencing analysis. Specific scores used for classifying features of dermoscopy (global pattern; 7-point check list; ABCD Stolz score) and confocal microscopy (Segura and Pellacani) were compared with genetic and histological data. Results: Consistency in dermoscopic patterns between the primary and subsequent cutaneous melanomas were observed in about two thirds of cases, whereas concordant features based on confocal microscopy were found in only about two fifths of cases. The majority of patients (7/12; 58%) presented consistent BRAF/NRAS mutation patterns between first and subsequent primary melanomas. A significant association between BRAF mutations and Pellacani score was evident. Conclusions: Similarities between the index melanoma and subsequent cutaneous melanomas were observed with regards to dermoscopic features and, to a much less extent, confocal microscopy findings. Our data further indicate that the Pellacani score may be used to predict BRAF mutations.

Interest on the genus Camelina has recently increased due to the biofuel, or jet fuel, potential of the oil extracted from seeds of the cultivated species Camelina sativa (L.) Crantz. While our knowledge on C. sativa is constantly augmenting, only few studies have been performed on the other species of the genus, which could be a potentially useful material for the genetic improvement of C. sativa. The genus Camelina consists of 11 species, but only six (C. sativa, C. microcarpa, C. alyssum, C. rumelica, C. hispida and C. laxa) could be retrieved from germplasm banks to carry out genomic fingerprinting studies based on the use of the cTBP molecular marker. Each species, with the exception of C. alyssum that is proposed to be a subspecies of C. sativa, shows a distinct cTBP profile resulting from multiple DNA length polymorphisms present in the second intron of the members of the β-tubulin gene family. In contrast to the high level of genetic diversity detected among the six Camelina species, low variability is observed among and within the accessions of the same species, except for C. hispida that is characterized by an intra-accession high number of cTBP polymorphic bands. In addition, cTBP is also able to identify incorrectly classified accessions and provide information on the ploidy level of each species.

Cutaneous melanoma is a common and aggressive human skin cancers. Much is actually known about the molecular mechanisms underlying melanoma pathogenesis. The aim of the study was to evaluate any possible correlation between mutations in main growth-controlling genes (BRAF, NRAS, CDKN2A) and copy number variations in frequently amplified candidate genes (MITF, EGFR, CCND1, cMET, and cKIT) during melanoma initiation and progression. A large series of primary and secondary melanoma tissue samples (N = 274) from 232 consecutively-collected patients of Italian origin as well as 32 tumor cell lines derived from primary and metastatic melanomas underwent mutation screening and fluorescence in situ hybridization (FISH) analysis. Overall, BRAF, NRAS, and CDKN2A were found mutated in 62.5%, 12.5% and 59% cell lines and in 47%, 16%, 12% tumor tissues, respectively. Quite identical mutation patterns between primary tumors and metastatic lesions were found for BRAF and NRAS genes; mutations of CDKN2A gene appeared to be instead selected during tumor progression. In cell lines, high rates of gene amplifications were observed (varying from 12.5% for cKIT to 50% for MITF); vast majority of cell lines (75%) presented at least one amplified gene. Conversely, prevalence of gene amplification was significantly and progressively decreasing in melanoma metastases (12%) and primary melanomas (4%). Our findings suggest that gene amplifications may be acquired during the late phases of melanoma evolution and mostly act as "passenger" or "non-causative" alterations.

Long non-coding RNAs cover large part of the non-coding information of the human DNA, which represents more than 90% of the whole genome. They constitute a wide and complex group of molecules with more than 200 nucleotides, which generally lack an open reading frame, and are involved in various ways in the pathophysiology of cancer. Their roles in the regulation of gene expression, imprinting, transcription, and post-translational processing have been described in several types of cancer. CASC2 was discovered in 2004 in patients with endometrial carcinoma as a potential tumor suppressor. Since then, additional studies in other types of neoplasia have been carried out, and both mechanisms and interactions of CASC2 in cancer have been better elucidated. In this review, we summarize the current knowledge on the role of CASC2 in the genesis, progression, and clinical management of human cancer.

Background: Racial and geographic factors seem to affect the incidence of cutaneous and mucosal melanoma. Objective: To investigate the occurrence of BRAF and cKIT impairments in patients with sinonasal melanoma in Southern Italy. Methods: Eleven sinonasal melanomas were screened for BRAF mutations and cKIT alterations by immunohistochemistry (CD117), fluorescence in situ hybridization and sequencing analyses. Results: A high prevalence (4/11; 36%) of BRAF mutations and lack of cKIT mutations were observed. Amplification of cKIT was found in 18% of cases; cKIT expression was detectable in 18% non-overlapping cases. No correlation between CD117 and cKIT alterations was observed. One (6%) cKIT and two (12%) BRAF mutations were detected in an additional series of 17 acral/mucosal melanomas from the same geographic areas. Conclusion: Mutations of cKIT are infrequent in sinonasal melanoma in Southern Italy.

Background Activation of oncogenes downstream the EGFR gene contributes to colorectal tumorigenesis and determines the sensitivity to anti-EGFR treatments. The aim of this study was to evaluate the prognostic value of KRAS, BRAF, NRAS and PIK3CA mutations in a large collection of CRC patients from genetically-homogeneous Sardinian population. Methods A total of 1284 Sardinian patients with histologically-proven diagnosis of colorectal carcinoma (CRC) and presenting with metastatic disease were included into the study. Genomic DNA was isolated from formalin-fixed, paraffin-embedded primary tumour tissue samples of CRC patients and screened for mutations in RAS and BRAF genes, using pyrosequencing assays, and in PIK3CA gene, using automated DNA sequencing assays. Results Overall, mutation rates were 35.6 % for KRAS, 4.1 % for NRAS, and 2.1 % for BRAF. Among available DNA samples, 114/796 (14.3 %) primary CRCs were found to carry a mutation in the PIK3CA gene. In this subset of patients analysed in all four genes, a pathogenetic mutation of at least one gene was discovered in about half (378/796; 47.5 %) of CRC cases. A mutated BRAF gene was found to steadily act as a negative prognostic factor for either time to progression as metastatic disease (from detection of primary CRC to diagnosis of first distant metastasis; p = 0.009) or partial survival (from diagnosis of advanced disease to the time of death or last control; p = 0.006) or overall survival (p

We have developed a new version of the cTBP (combinatorial tubulin-based polymorphism) method, a previously described approach based on intron-length polymorphism (ILP), to rapidly characterize the β-tubulin gene family of Camelina sativa (L.) Crantz, a plant species of importance for oil production but still largely unexplored at genomic level. The method, named h-TBP, allows the rapid cloning of the β-tubulin genomic sequences that encompass the two introns, invariantly present at fixed positions within the coding region of the vast majority of the plant species. The β-tubulin sequences cloned by h-TBP also comprise part of exon1 and exon3 and the whole sequence of exon2. The h-TBP method has then been used to isolate, clone and characterize the β-tubulin gene family of C. sativa, composed of at least 20 different β-tubulin isotypes, named CsTUB1 through CsTUB20. The relatively high number of β-tubulin genes has been further substantiated by Southern-blot analysis. Comparison of the β-tubulin exon sequences of C. sativa with those of Arabidopsis thaliana, the closest relative among crucifers, defines distinct groups of putative orthologous genes, identified by a UPMGA cluster analysis. Analysis of the C. sativa β-tubulin intron sequences reveals some molecular features that can provide the first hints for the understanding of intron plasticity and evolution. From a more immediate perspective, these data provide the first substantial contribution to the characterization of the largely unexplored genome of C. sativa, and the tools for assisting programmes of breeding and selection of the most productive plants.

e21554Background: The prevalence of mutations in main genes involved in tumorigenesis during melanoma progression remains a controversial issue. Different melanoma tissues from the same patients we...

There seem to be a certain degree of reluctance in accepting ILP-based methods as part of the range of molecular markers that are classically used for plant genotyping. Indeed, since DNA polymorphism results from difference in length of fragments amplified from specific gene loci, not anonymous sequences, the number of markers that can be generated is sometime inadequate for classical phylogeny studies. Yet, ILP-based markers have many other useful advantages that should not go neglected. We support this statement by presenting a large variety of data we have been collecting for a long while regarding the use of cTBP, an ILP marker based on difference in length of the introns present within the members of the plant beta-tubulin gene family.

Molecular mechanisms involved in pathogenesis of malignant melanoma have been widely studied and novel therapeutic treatments developed in recent past years. Molecular targets for therapy have mostly been recognized in the RAS-RAF-MEK-ERK and PI3K-AKT signaling pathways; small-molecule inhibitors were drawn to specifically target key kinases. Unfortunately, these targeted drugs may display intrinsic or acquired resistance and various evidences suggest that inhibition of a single effector of the signal transduction cascades involved in melanoma pathogenesis may be ineffective in blocking the tumor growth. In this sense, a wider comprehension of the multiple molecular alterations accounting for either response or resistance to treatments with targeted inhibitors may be helpful in assessing, which is the most effective combination of such therapies. In the present review, we summarize the known molecular mechanisms underlying either intrinsic and acquired drug resistance either alternative roads to melanoma pathogenesis, which may become targets for innovative anticancer approaches.

Background: Activated PI3K-AKT pathway may contribute to decrease sensitivity to inhibitors of key pathogenetic effectors (mutated BRAF, active NRAS or MEK) in melanoma. Functional alterations are deeply involved in PI3K-AKT activation, with a minimal role reported for mutations in PIK3CA, the catalytic subunit of the PI3K gene. We here assessed the prevalence of the coexistence of BRAF/NRAS and PIK3CA mutations in a series of melanoma samples. Methods: A total of 245 tumor specimens (212 primary melanomas and 33 melanoma cell lines) was screened for mutations in BRAF, NRAS, and PIK3CA genes by automated direct sequencing. Results: Overall, 110 (44.9%) samples carried mutations in BRAF, 26 (10.6%) in NRAS, and 24 (9.8%) in PIK3CA. All identified PIK3CA mutations have been reported to induce PI3K activation; those detected in cultured melanomas were investigated for their interference with the antiproliferative activity of the BRAF-mutant inhibitor vemurafenib. A reduced suppression in cell growth was observed in treated cells carrying both BRAF and PIK3CA mutations as compared with those presenting a mutated BRAF only. Among the analysed melanomas, 12/245 (4.9%) samples presented the coexistence of PIK3CA and BRAF/NRAS mutations. Conclusions: Our study further suggests that PIK3CA mutations account for a small fraction of PI3K pathway activation and have a limited impact in interfering with the BRAF/NRAS-driven growth in melanoma.

Background: Assessment of the mutational status in EGFR, KRAS, BRAF has become crucial in recent years for the molecular classification of patients with non small cell lung cancer (NSCLC). In this population-based study, we evaluated the incidence rates and distribution of such somatic mutations among NSCLC patients in genetically isolated population from Sardinia. Material and methods: From July 2010, a total of 1,047 formalin-fixed paraffin-embedded tumor tissues from patients with NSCLC and ascertained Sardinian origin was prospectively collected at clinics across the entire island. Genomic DNA was isolated from tissue sections and screened for somatic mutations in EGFR, KRAS, and BRAF genes by automated DNA sequencing. Results: Overall, 112 (10.7%) analyzed patients carried an EGFR mutation. Somatic mutations in EGFR gene were quite equally distributed between exon 19 (57/112; 51%) and exon 21 (52/112; 46%), with few mutations (3/112; 3%) in exon 18 of EGFR. No significant difference in distribution of EGFR mutations according to the age at diagnosis was observed [EGFR mutant: median age, 67 (range, 37-85); EGFR wild-type: median age, 65 (range, 35-89)]. Females presented a significantly higher frequency of EGFR mutations in comparison to males (23.6% vs. 5.7%, respectively] (p = 0.003). According to the smoking history, a significant preponderance of EGFR mutations were observed in never smokers (43.2%) as compared to former smokers (5.8%) and smokers (3.6%) (p < 0.001). Among 634 patients whose somatic DNA was available for further analyses [71 (11.2%) cases carried EGFR mutations], we detected 138 cases (21.8%) with KRAS mutations and 3 (0.5%) with BRAF mutation (V600E). KRAS and BRAF mutations were significantly more prevalent in males than females (22.4% vs. 10.3%, respectively; p = 0.012) as well as in smokers (31.8%) than in former smokers (17.6%) or never smokers (4.5%) (p = 0.023). In this series, no concomitant mutations in EGFR, KRAS, and BRAF genes were detected. Therefore, two thirds (422/ 634; 66.6%) of such patients lacked somatic mutations in all three analyzed genes. Conclusions: Although the prevalence of mutations in the three main candidate gens among NSCLC patients from Sardinia was consistent with that reported in literature for Western populations, their distribution varied into the different clinical subgroups

Interest on the genus Camelina has recently increased due to the biofuel, or jet fuel, potential of the oil extracted from seeds of the cultivated species Camelina sativa (L.) Crantz. While our knowledge on C. sativa is constantly augmenting, only few studies have been performed on the other species of the genus, which could be a potentially useful material for the genetic improvement of C. sativa. The genus Camelina consists of 11 species, but only six (C. sativa, C. microcarpa, C. alyssum, C. rumelica, C. hispida and C. laxa) could be retrieved from germplasm banks to carry out genomic fingerprinting studies based on the use of the cTBP molecular marker. Each species, with the exception of C. alyssum that is proposed to be a subspecies of C. sativa, shows a distinct cTBP profile resulting from multiple DNA length polymorphisms present in the second intron of the members of the ?-tubulin gene family. In contrast to the high level of genetic diversity detected among the six Camelina species, low variability is observed among and within the accessions of the same species, except for C. hispida that is characterized by an intra-accession high number of cTBP polymorphic bands. In addition, cTBP is also able to identify incorrectly classified accessions and provide information on the ploidy level of each species.

Allelic deletions, which are suggestive for the presence of tumor suppressor genes, represent a common event in endometrial cancer (EC). Previous loss-of-heterozygosity studies for human chromosome 10q identified a candidate deletion interval at 10q25-q26, which we further narrowed to a 160-kb region at 10q26, bounded by markers D10S1236 and WIAF3299. Using a positional candidate approach, we identified three alternative transcripts of a novel human gene, CASC2 (cancer susceptibility candidate 2; formely C10orf5). One of such transcripts, CASC2a, encodes a short protein of 102 amino acids with no similarity to any other known gene product. Three (7%) CASC2a mutations were identified in tumor DNA from 44 EC patients. While c.-156G>T and c.22C>T (p.Pro8Ser) are sequence variants with unknown functional significance, c.84delA is a mutation with a truncation effect on the predicted protein (p. Asn28fsX50). Expression studies by real-time RT-PCR on several normal and tumor cells revealed that CASC2a mRNA is downregulated in cancer, suggesting that it may act as a potential tumor suppressor gene. The very low mutation rate seems to also indicate that inactivation of CASC2a might probably be due to mechanisms different from genetic alterations.

Purpose Oncogenic activation of the BRAF gene has been demonstrated to be involved in the pathogenesis of malignant melanoma (MM). In this study, we investigated the contribution of BRAF to melanoma susceptibility, also making a comparison with frequency of CDKN2A germline mutations in MM patients from different areas in Italy. Patients and Methods Using a combination of denaturing high-performance liquid chromatography analysis and automated sequencing on genomic DNA from peripheral blood or tumor tissue samples, 569 MM patients (211 from northern Italy and 358 from southern Italy) were screened for BRAF mutations. Results Three BRAF germline sequence variants (M116R, V599E, and G608H) were identified in four (0.7%) of 569 MM patients. The most common BRAF mutation, V599E, was detected in one germline DNA sample only; M116R and G608H were newly described mutations. A high frequency (59%) of BRAF mutations was instead observed in tumor samples from patients also undergoing germline DNA analysis; at the somatic level, substitution of valine 599 was found to account for the majority (88%) of BRAF mutations. We then estimated the germline mutation rates in BRAF and CDKN2A among 358 consecutively collected patient samples originating in southern Italy; a low (2.5%) or very low (0.29%) prevalence of CDKN2A and BRAF mutations, respectively, was detected. Conclusion Mutation analysis of either blood DNA from a large collection of MM patients or matched MM tissues from a subset of such patients revealed that BRAF is somatically mutated and does not play a major role in melanoma susceptibility. The present study further suggests that patient origin may account for different mutation rates in candidate genes.

e21047 Background: The prevalence of mutations in driver genes during progression in cutaneous and mucosal melanomas remains inconclusive. We investigated the prevalence and distribution of mutations in main candidate genes involved in melanomagenesis among different melanoma tissues using a next-generation sequencing (NGS) approach. Methods: Forty-eight tumor samples from 36 patients with mucosal melanoma (MM) and fifty-two tumor samples from 34 patients with cutaneous melanoma (CM) were collected, after obtaining patients’ written informed consent for tissue sampling. Genomic DNA was isolated from macrodissected tumor tissues containing at least 80% neoplastic cells and analyzed for mutations in 25 most common melanoma-associated oncogenes and tumor suppressor genes, using the IMI Diagnostic Melanoma Panel on the Ion Torrent platform (Life Technologies, USA). Results: A total of 100 tumor tissues from 70 melanoma patients were analyzed. BRAF mutations were detected in 21/34 (62%) CM patients and 13/36 (36%) mm patients. The second most prevalent mutations were found in K-/N-RAS (6/34; 18%) and cKIT (6/36; 17%) genes among CM and mm patients, respectively. No concomitant mutations of BRAF, RAS, and cKIT genes were detected. Among others, mutations were more frequently found in CCND1 (20%), ARID2 (16%), and NF1(12%) genes, considering the entire series of patients. Vast majority of patients who had paired samples of primary and secondary melanomas showed consistent mutation patterns between primary tumors and metastatic lesions. Similar frequencies of mutations in driver genes were seen across metastatic sites. Conclusions: In the era of targeted therapies, assessment of the spectrum and distribution of mutations in main molecular targets among patients with melanoma is needed. Our findings about the prevalence of mutations in driver genes in paired tumor lesions from patients with cutaneous and mucosal melanoma may be useful in the management of such diseases. The Italian Melanoma Intergroup (IMI) includes the following additional members who participated as investigators in this study: Mario Mandalà, Paola Queirolo, Ignazio Stanganelli, Vanna Chiarion Sileni, Pietro Quaglino, Anna Maria Di Giacomo.

Background: Alterations in key-regulator genes of disease pathogenesis (BRAF, cKIT, CyclinD1) have been evaluated in patients with multiple primary melanoma (MPM). Methods: One hundred twelve MPM patients (96 cases with two primary melanomas, 15 with three, and 1 with four) were included into the study. Paired synchronous/asynchronous MPM tissues (N = 229) were analyzed for BRAF mutations and cKIT/CyclynD1 gene amplifications. Results: BRAF mutations were identified in 109/229 (48%) primary melanomas, whereas cKIT and CyclinD1 amplifications were observed in 10/216 (5%) and 29/214 (14%) tumor tissues, respectively. While frequency rates of BRAF mutations were quite identical across the different MPM lesions, a significant increase of cKIT (p < 0.001) and CyclinD1 (p = 0.002) amplification rates was observed between first and subsequent primary melanomas. Among the 107 patients with paired melanoma samples, 53 (49.5%) presented consistent alteration patterns between first and subsequent primary tumors. About one third (40/122; 32.8%) of subsequent melanomas presented a discrepant pattern of BRAF mutations as compared to incident primary tumors. Conclusions: The low consistency in somatic mutation patterns among MPM lesions from same patients provides further evidence that melanomagenesis is heterogeneous and different cell types may be involved. This may have implications in clinical practice due to the difficulties in molecularly classifying patients with discrepant primary melanomas.