Background: Colorectal cancer (CRC) is the third most diagnosed malignancy and the second leading cause of cancer-related mortality worldwide. Recent therapeutic advancements have significantly improved clinical management, underscoring the importance of routine molecular profiling to guide personalised treatment strategies. This study aims to evaluate the prognostic impact of main molecular alterations-including allele frequency (AF) of RAS mutations-on survival outcomes in a real-world hospital-based cohort of patients with metastatic CRC. Methods: A total of 208 consecutive patients with a histologically confirmed diagnosis of CRC and complete clinical, molecular, and survival data were retrospectively analysed. Somatic mutations in KRAS, NRAS, BRAF, and the occurrence of microsatellite instability (MSI) were assessed using pyrosequencing and real-time PCR assays, respectively, on formalin-fixed, paraffin-embedded tumour samples. Associations between mutational status, clinicopathological parameters, and overall survival (OS) were evaluated. Results: Overall, 138 patients (66.3%) harboured at least one somatic mutation: 115 (55.3%) in KRAS, 8 (3.8%) in NRAS, and 15 (7.2%) in BRAF. MSI was detected in 17/208 (8.2%) patients. A statistically significant improvement in OS was observed in patients lacking mutations in any of the three genes-referred to as wild-type (WT) patients-with BRAF mutated cases showing the worst survival (p = 0.041). Increasing age at the time of first-line therapy for advanced disease stage was associated with a statistically significant increase in the hazard of death (p = 0.031). Conclusions: In the advanced disease stage, RAS/BRAF wild-type colorectal cancers were significantly associated with a survival advantage.

Mutations in the KRAS gene are prominent oncogenic drivers in non-small cell lung cancer (NSCLC), with multiple pathophysiological, clinical and prognostic implications. Although historically considered an "undruggable" target, recent research led to the development of specific KRAS-G12C inhibitors, like sotorasib and adagrasib which are currently approved for clinical use in patients affected by advanced NSCLC. However, the clinical utility of these drugs is often limited by resistance development through several biological mechanisms, including additional KRAS mutations, activation of compensatory pathways and metabolic reprogramming. In addition, the immunosuppressive tumor microenvironment (TME) in KRAS-mutant NSCLC reduces the efficacy of immune checkpoint inhibitors (ICIs), further complicating treatment and clinical outcomes. Combination therapy with KRAS inhibitors, ICIs, and other agents appears currently as an attractive option for overcoming resistance and improving survival in these patients. This review provides a detailed overview of KRAS genetic alterations in NSCLC, focusing on the involved molecular pathways, current and potential targeted therapies, challenges related to tumor heterogeneity, as well as ongoing research and future perspectives. In addition, the role of TME in generating treatment resistance is discussed, along with emerging therapeutic options that target non-G12C KRAS mutations or combine different pharmacological approaches to disrupt both oncogenic signaling and immune evasion.

Background Patients with pancreatic ductal adenocarcinoma (PDCA) carrying impaired mismatch repair mechanisms seem to have an outcome advantage under treatment with conventional chemotherapy, whereas the role for the tumor mutation burden on prognosis is controversial. In this study, we evaluated the prognostic role of the mutated genes involved in genome damage repair in a real-life series of PDAC patients in a hospital-based manner from the main Institution deputed to surgically treat such a disease in North Sardinia. Methods A cohort of fifty-five consecutive PDAC patients with potentially resectable/border line resectable PDAC (stage IIB-III) or oligometastatic disease (stage IV) and tumor tissue availability underwent next-generation sequencing (NGS)-based analysis using a panel containing driver oncogenes and tumor suppressor genes as well as genes controlling DNA repair mechanisms. Results Genes involved in the both genome damage repair (DR) and DNA mismatch repair (MMR) were found mutated in 17 (31%) and 15 (27%) cases, respectively. One fourth of PDAC cases (14/55; 25.5%) carried tumors presenting a combination of mutations in repair genes (DR and MMR) and the highest mutation load rates (MLR-H). After correction for confounders (surgery, adjuvant therapy, stage T, and metastasis), multivariate Cox regression analysis indicated that mutations in DR genes (HR = 3.0126, 95% CI 1.0707 to 8.4764, p = 0.0367) and the MLR (HR = 1.0018, 95%CI 1.0005 to 1.0032, p = 0.009) were significantly related to worse survival. Conclusions The combination of mutated repair genes and MLR-H, which is associated with a worse survival in our series of PDAC patients treated with conventional chemotherapy protocols, might become a predictive biomarker of response to immunotherapy in addition to its prognostic role in predicting survival.

Abstract 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 < 0.0001); conversely, KRAS mutations were associated with a significantly lower survival (p = 0.0058). Among LAC patients with additional tissue section available for next-generation sequencing (NGS)-based analysis, 26/193 (13.5%) patients found positive for even low-rate EGFR-T790M mutated alleles at baseline were associated with a highly significant lower survival in comparison to those without (8.7 vs. 47.4 months, p < 0.0001). Conclusions In addition to its predictive value for addressing targeted therapy approaches, the assessment of as more inclusive mutation analysis at baseline may provide clues about factors significantly impacting on global survival in advanced LAC patients.

Background Rechallenge with EGFR inhibitors represents a promising strategy for patients with RAS wild type (WT) colorectal cancer (CRC) but definitive selection criteria are lacking. Recently, the RAS WT status on circulating tumor DNA (ct-DNA) emerged as a potential watershed for this strategy. Our study explored the liquid biopsy-driven cetuximab rechallenge in a RAS and BRAF WT selected population. Methods CRC patients with RAS and BRAF WT both on tumor tissue and on ct-DNA at baseline receiving rechallenge with cetuximab were eligible for our analysis. Ct-DNA was analyzed for RAS-BRAF mutations with pyro-sequencing and nucleotide sequencing assays. Real-time PCR and droplet digital PCR were performed to confirm the RAS-BRAF mutational status. Results A total of 26 patients were included in our analysis. In the global population, RR was 25.0%, median overall survival (mOS) was 5.0 months, and median progression-free survival (mPFS) was 3.5 months. Previous response to anti-EGFR was associated with improved mPFS (5.0 vs. 2.0 months, HR: 0.26, p = 0.048); anti-EGFR free interval > 14 months and anti-EGFR free interval > 16 months were associated with improved mPFS (respectively 7.0 vs. 3.0 months, HR: 0.27, p = 0.013 and not reached vs. 3.0 months, HR: 0.20, p = 0.002) and with improved mOS (respectively 13.0 vs. 5.0 months, HR: 0.27, p = 0.013 and 13.0 vs. 5.0 months, HR: 0.20, p = 0.002). Previous lines >2 were correlated with improved mPFS (4.0 vs. 1.0 month, HR: 0.05, p = 0.041) and with improved mOS (7.0 vs. 1.0 month, HR: 0.045, p = 0.034). In a multiple logistic regression model, only the anti-EGFR free interval was confirmed to be a significant predictor for mOS and mPFS. Conclusions Liquid biopsy-driven cetuximab rechallenge was confirmed to be effective. The clinical outcome was consistent with available results from phase II studies. In addition to the molecular selection through the analysis of ct-DNA for RAS, the long anti-EGFR free interval is confirmed as a prospective selection criterion for this therapeutic option.

3577 Background: The rechallenge with EGFR inhibitors represents an emerging strategy for anti-EGFR pre-treated patients with RAS wild type colorectal cancer (CRC). Unfortunately definitive selection criteria for anti-EGFR rechallenge in this setting are lacking. Very recently RAS wild type status on circulating tumor DNA (ct-DNA) at the time of rechallenge along with already known clinical criteria emerged as a potential watershed for this strategy. In the present study we explored liquid biopsy-driven anti-EGFR rechallenge strategy in the clinical practice for patients with metastatic colorectal cancer. Methods: Ct-DNA from RAS and BRAF wild type metastatic CRC patients previously treated with an anti-EGFR containing therapy was analyzed for RAS/BRAF mutations with the aim to evaluate the rechallenge strategy with anti-EGFR. The ct-DNA was analyzed for RAS-BRAF mutations using pyro-sequencing (PyroMark Q24 MDx Workstation) and nucleotide sequencing (Genetic Analyzer ABI3130) assays. Real-time PCR (Idylla) and droplet digital PCR (QX200 System) were performed to confirm the RAS-BRAF mutation status. Several clinical variables including previous response to anti EGFR containing therapy, tumor sidedness and anti-EGFR free interval were evaluated in relation to outcome. Tumor response evaluation was performed according to RECIST 1.1. Differences between categorical variables were evaluated using the Fisher’s exact test. Survival probability over time was estimated by the Kaplan–Meier method. Significant differences in the probability of survival between the strata were evaluated by log-rank test. Results: Twenty patients were included in the study. All patients were tested for RAS-BRAF mutations in ct-DNA. Fourteen patients (70%) showed a RAS-BRAF WT molecular profile, six patients (30%) showed a KRAS mutation. All the patients with ct-DNA RAS-BRAF WT profile underwent rechallenge with anti-EGFR. In details 11 patients (78.6%) underwent irinotecan+ cetuximab treatment, whereas 3 patients (21.4%) underwent panitumumab monotherapy. As for the outcome results to the rechallenge strategy, the median OS was 7 months (95% CI 5.0 to 13.0), the median PFS was 3 months (95% CI 2.0 to 6.0), the ORR was 27.3% with a DCR of 54.5%. Among the clinical variables evaluated as putative predictive/prognostic factors, previous response to anti-EGFR treatment was related to a not statistically significant improved OS (12 months vs 5 months HR:0.19 p: 0.06) and to a statistically significant improved ORR (75% vs 0% p:0.03). Conclusions: The rechallenge strategy with anti-EGFR confirmed to be feasible in clinical practice. The clinical outcome resulted consistent with the literature data. In addition to the molecular selection through the analysis of ct-DNA for RAS, previous response to anti EGFR treatment is confirmed as a prospective selection criteria for this therapeutic option.

Background: Next-generation sequencing (NGS) needs to be validated and standardized to ensure that cancer patients are reliably selected for target treatments. In Italy, NGS is performed in several institutions and harmonization of wet and dry procedures is needed. To this end, a consortium of five different laboratories, covering the most part of the Italian peninsula, was constituted. A narrow gene panel (SiRe®) covering 568 clinically relevant mutations in six different genes (EGFR, KRAS, NRAS, BRAF, cKIT, and PDGFRα) with a predictive role for therapy selection in non-small cell lung cancer (NSCLC), gastrointestinal stromal tumor, colorectal carcinoma (CRC), and melanoma was evaluated in each participating laboratory. Methods: To assess the NGS inter-laboratory concordance, the SiRe® panel, with a related kit and protocol for library preparation, was used in each center to analyze a common set of 20 NSCLC and CRC routine samples. Concordance rate, in terms of mutation detected and relative allelic frequencies, was assessed. Then, each institution prospectively analyzed an additional set of 40 routine samples (for a total of 160 specimens) to assess the reproducibility of the NGS run parameters in each institution. Results: An inter-laboratory agreement of 100% was reached in analyzing the data obtained from the 20 common sample sets; the concordance rate of allelic frequencies distribution was 0.989. The prospective analysis of the run metric parameters obtained by each center locally showed that the analytical performance of the SiRe® panel in the different institutions was highly reproducible. Conclusions: The SiRe® panel represents a robust diagnostic tool to harmonize the NGS procedure in different Italian laboratories.

Maria Cristina Sini*, Grazia Palomba*, Marina Pisano, Carla Rozzo, Antonella Manca, Ivana Persico, Laura Frogheri, Maria Grazia Doro, Giuseppe Palmieri Collaborating Institutions: Università degli Studi di Sassari; Azienda Ospedaliero Universitaria (AOU), Sassari; Senologia Multidisciplinare Aziendale Coordinata (SMAC), AOU Sassari; Ospedale Mater Olbia, Olbia; Italy. *These authors contributed equally

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.

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.

The objective of this population-based study is to describe epidemiological and genetic features of breast and ovarian cancer in North Sardinia, Italy.Patients who carry a high-risk mutation in one or both of the BRCA genes (BRCA1 or BRCA2) have a significantly increased risk of developing breast/ovarian cancer (BOC) and other cancers (e.g., prostate cancer in male).Epidemiological data on incidence distribution of breast/ovarian cancer from 2016 to 2019 in North Sardinia are obtained from the local tumor registry and from the cumulative results of 209 genetic testing for BRCA gene mutations performed in all young breast cancer patients and all women (over 50 years) with family history of BOC (total of 164 cases); further, 45 genetic testing is performed, on ovarian cancer patients, at any age.The results provide a different distribution of fraction mutations carried by women and a higher prevalence of the BRCA2 mutation in the north of Sardinia than the entire population and highlight the presence of specific germline mutation associated with the "founder effect" in distinct genetic subgroups reflecting genetic drift.Advances in next-generation sequencing technology, data analysis, and clinical investigation have revolutionized efforts to identify potential targets for BRCA molecular-based therapeutic agents.

Maria Colombino*, Antonella Manca*, Milena Casula, Carla Rozzo, Marina Pisano, Giambattista Maestrale, Stefania Casula, Giuseppina Casu, Grazia Palomba, Giuseppe Palmieri Collaborating Institutions: Università degli Studi di Sassari e di Cagliari; Azienda Ospedaliero Universitaria (AOU), Sassari; Università degli Studi di Cagliari, Cagliari; Istituto Nazionale Tumori “Fondazione Pascale”, Napoli; Italy The Italian Melanoma Intergroup (IMI). *These authors contributed equally

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:Lung cancer is one of the most incident neoplastic diseases, and a leading cause of death for cancer worldwide. Knowledge of the incidence of druggable genetic alterations, their correlation with clinical and pathological features of the disease, and their interplay in cases of co-occurrence is crucial for selecting the best therapeutic strategies of patients with non-small cell lung cancer. In this real-life study, we describe the molecular epidemiology of genetic alterations in five driver genes and their correlations with the demographic and clinical characteristics of Sardinian patients with lung adenocarcinoma. METHODS:Data from 1440 consecutive Sardinian patients with a histologically proven diagnosis of lung adenocarcinoma from January 2011 through July 2016 were prospectively investigated. EGFR mutation analysis was performed for all of them, while KRAS and BRAF mutations were searched in 1047 cases; ALK alterations were determined with fluorescence in situ hybridization in 899 cases, and cMET amplifications in 788 cases. RESULTS:KRAS mutations were the most common genetic alterations involving 22.1% of the cases and being mutually exclusive with the EGFR mutations, which were found in 12.6% of them. BRAF mutations, ALK rearrangements, and cMET amplifications were detected in 3.2, 5.3, and 2.1% of the cases, respectively. Concomitant mutations were detected only in a few cases. CONCLUSIONS:Almost all the genetic alterations studied showed a similar incidence in comparison with other Caucasian populations. Concomitant mutations were rare, and they probably have a scarce impact on the clinical management of Sardinians with lung adenocarcinoma. The low incidence of concomitant cMET amplifications at diagnosis suggests that these alterations are acquired in subsequent phases of the disease, often during treatment with TKIs.

Cutaneous malignant melanoma is a heterogeneous disease, being the consequence of specific genetic alterations along several molecular pathways. Despite the increased knowledge about the biology and pathogenesis of melanoma, the incidence has grown markedly worldwide, making it extremely important to develop preventive measures. The beneficial role of correct nutrition and of some natural dietary compounds in preventing malignant melanoma has been widely demonstrated. This led to numerous studies investigating the role of several dietary attitudes, patterns, and supplements in the prevention of melanoma, and ongoing research investigates their impact in the clinical management and outcomes of patients diagnosed with the disease. This article is an overview of recent scientific advances regarding specific dietary compounds and their impact on melanoma development and treatment.

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.

Cutaneous malignant melanoma (CMM) is one of the most common skin cancers worldwide. Limited information is available in the current scientific literature on the concordance of genetic alterations between primary and metastatic CMM. In the present study, we performed next-generation sequencing (NGS) analysis of the main genes participating in melanoma pathogenesis and progression, among paired primary and metastatic lesions of CMM patients, with the aim to evaluate levels of discrepancies in mutational patterns. Paraffin-embedded tumor tissues of the paired lesions were retrieved from the archives of the institutions participating in the study. NGS was performed using a specific multiple-gene panel constructed by the Italian Melanoma Intergroup (IMI) to explore the mutational status of selected regions (343 amplicons; amplicon range: 125–175 bp; coverage 100%) within the main 25 genes involved in CMM pathogenesis; sequencing was performed with the Ion Torrent PGM System. A discovery cohort encompassing 30 cases, and a validation cohort including eleven Sardinian patients with tissue availability from both the primary and metachronous metastatic lesions were identified; the global number of analyzed tissue specimens was 90. A total of 829 genetic non-synonymous variants were detected: 101 (12.2%) were pathogenic/likely pathogenic, 131 (15.8%) were benign/likely benign, and the remaining 597 (72%) were uncertain/unknown significance variants. Considering the global cohort, the consistency in pathogenic/pathogenic like mutations was 76%. Consistency for BRAF and NRAS mutations was 95.2% and 85.7% respectively, without statistically significant differences between the discovery and validation cohort. Our study showed a high level of concordance in mutational patterns between primary and metastatic CMM, especially when pathogenic mutations in driver genes were considered.

e21554 Background: The prevalence of mutations in main genes involved in tumorigenesis during melanoma progression remains a controversial issue. Different melanoma tissues from the same patients were investigated for prevalence and distribution of mutations in these genes. Methods: Ninety-eight tumor tissues from 36 patients with metastatic melanoma patients were screened for sequence variants in a panel of 25 genes associated with cell cycle progression, cell differentiation, angiogenesis, and tumor growth by next generation sequencing (NGS) assays. Paired samples of primary melanomas (n = 36) and synchronous or asynchronous metastases from the same patients (n = 62) were included. Secondary lesions included lymph nodal (n = 28), subcutaneous (n = 19), and visceral (n = 15) tumor samples. Results: BRAF, CDKN2A, RAS, and TP53 genes were the most frequently mutated genes. Deleterious mutations were also found in also in ARID2, CDK4, NF1, CCND1, and PTEN genes. Of 28 patients with lymph node metastases, 23 (82%) presented consistent mutation patterns in paired primary and secondary tumor samples. For visceral metastases, 11/15 (73%) patients showed a similar mutation spectrum between primary and secondary tumors. A significantly less consistency was observed in skin metastases (11/19; 58%). Conclusions: Our findings are consistent with previous studies from our group (Colombino, JCO 2012; Casula JID 2016) indicating a low heterogeneity in matched primary and lymph node metastatic samples. Assessment of the prevalence of mutations in genes involved in melanomagenesis among paired tumor lesions from patients with metastatic melanoma may further improve the management of such a disease.

Female adnexal tumors of probable Wolffian origin are rare gynecologic tumors with <90 cases reported in the current scientific literature. Their clinical features have been described extensively; less is known about the pathophysiological mechanisms and the molecular alterations underlying their development and growth. We performed a complete histopathologic examination and a systematic mutation analysis using a next-generation sequencing approach on 3 female adnexal tumors of probable Wolffian origin from the archives of our institution to detect possible genetic alterations and to explore their role in the development of these rare tumors. The 3 cases contained missense mutations in different genes belonging to distinct molecular pathways: CTNNB1 and MET mutations for the first case, PIK3CA for the second one, and BRAF and CDKN2A for the third one. Two variants with an unknown functional effect on the protein were found in KDR and TP53 genes. In conclusion, genetic heterogeneity was found in our series. No constant involvement of the most common pathways involved in tumorigenesis was found; nevertheless, further studies are necessary to confirm the results of this pilot study.

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.