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1.
Int J Cancer ; 2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33527407

RESUMO

Incidence of differentiated thyroid carcinoma (DTC) varies considerably between ethnic groups, with particularly high incidence rates in Pacific Islanders. DTC is one of the cancers with the highest familial risk suggesting a major role of genetic risk factors, but only few susceptibility loci were identified so far. In order to assess the contribution of known DTC susceptibility loci and to identify new ones, we conducted a multiethnic genome-wide association study (GWAS) in individuals of European ancestry and of Oceanian ancestry from Pacific Islands. Our study included 1554 cases/1973 controls of European ancestry and 301 cases/348 controls of Oceanian ancestry from seven population-based case-control studies participating to the EPITHYR consortium. All participants were genotyped using the OncoArray-500K Beadchip (Illumina). We confirmed the association with the known DTC susceptibility loci at 2q35, 8p12, 9q22.33 and 14q13.3 in the European ancestry population and suggested two novel signals at 1p31.3 and 16q23.2, which were associated with thyroid-stimulating hormone levels in previous GWAS. We additionally replicated an association with 5p15.33 reported previously in Chinese and European populations. Except at 1p31.3, all associations were in the same direction in the population of Oceanian ancestry. We also observed that the frequencies of risk alleles at 2q35, 5p15.33 and 16q23.2 were significantly higher in Oceanians than in Europeans. However, additional GWAS and epidemiological studies in Oceanian populations are needed to fully understand the highest incidence observed in these populations.

2.
Invest New Drugs ; 2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33300108

RESUMO

Objectives Malignant pleural mesothelioma (MPM) is an occupational disease mainly due to asbestos exposure. Effective therapies for MPM are lacking, making this tumour type a fatal disease. Materials and Methods In order to meet this need and in view of a future "drug repositioning" approach, here we screened five MPM (Mero-14, Mero-25, IST-Mes2, NCI-H28 and MSTO-211H) and one SV40-immortalized mesothelial cell line (MeT-5A) as a non-malignant model, with a library of 1170 FDA-approved drugs. Results Among several potential compounds, we found that fludarabine (F-araA) and, to a lesser extent, risedronic acid (RIS) were cytotoxic in MPM cells, in comparison to the non-malignant Met-5A cells. In particular, F-araA reduced the proliferation and the colony formation ability of the MPM malignant cells, in comparison to the non-malignant control cells, as demonstrated by proliferation and colony formation assays, in addition to measurement of the phospho-ERK/total-ERK ratio. We have shown that the response to F-araA was not dependent upon the expression of DCK and NT5E enzymes, nor upon their functional polymorphisms (rs11544786 and rs2295890, respectively). Conclusion This drug repositioning screening approach has identified that F-araA could be therapeutically active against MPM cells, in addition to other tumour types, by inhibiting STAT1 expression and nucleic acids synthesis. Further experiments are required to fully investigate this.

3.
Thyroid ; 2020 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-33308024

RESUMO

BACKGROUND: Galectin-3 (LGALS3) is an important glycoprotein involved in the malignant transformation of thyrocytes acting in the extracellular matrix, cytoplasm and nucleus where it regulates TTF-1 and TCF4 transcription factors. Within LGALS3 gene, a common genetic polymorphism (c.191C>A, p.Pro64His; rs4644) encoding for the variant Proline to Histidine at codon 64 has been extensively studied. However, data on rs4644 in the context of thyroid cancer are lacking. Thus, the aim of the present work was to evaluate the role of the SNP rs4644 as risk factor for differentiated thyroid cancer (DTC) and to verify the effect on the transcriptome in thyrocytes. METHODS: A case-control association study on 1223 controls and 1142 unrelated consecutive DTC patients was carried out to evaluate the association between rs4644-P64H and the risk of DTC. Moreover, we employed the non-malignant cell line Nthy-Ori (rs4644-C/A) and the CRISPR/Cas9 technique to generate isogenic cells carrying either the rs4644-A/A or rs4644-C/C homozygosis. Then, the transcriptome of the derivative and unmodified parental cells was analyzed by RNA-seq. Genes differentially expressed in a statistically significant way were validated by RT-qPCR and further tested in the parental Nthy-Ori cells after LGALS3 gene silencing, to investigate whether the expression of target genes was dependent also upon the galectin-3 levels. RESULTS: Rs4644 AA genotype was associated with a reduced risk of DTC (compared to CC, ORadj=0.66; 95%CI=0.46-0.93; Pass=0.02). Moreover, we showed that rs4644 affects galectin-3 as transcriptional co-regulator. Among 34 genes affected by rs4644 HES1, HSPA6, SPC24, and NHS were of particular interest since their expression was rs4644-dependent (CC>AA for the first and AA>CC for the others) also in 574 thyroid tissues of GTex biobank (https://gtexportal.org/home/index.html). Moreover, the expression of these genes was sensible to LGALS3-silencing. We hypothesized that rs4644 could alter the transcription of target genes by modulating the interaction with TTF-1. Indeed, the proximity ligation assay in Nthy-Ori cells showed that the interaction was genotype-dependent. CONCLUSIONS: Our data showed that in thyroid rs4644 is a trans-expression quantitative trait locus that can modify the transcriptional expression of downstream genes, through the modulation of TTF-1 and, likely, also of other transcriptional factors such as TCF4.

4.
Int J Cancer ; 2020 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-33038278

RESUMO

Myeloproliferative neoplasms (MPNs) are a group of diseases that cause myeloid hematopoietic cells to overproliferate. Epidemiological and familial studies suggest that genetic factors contribute to the risk of developing MPN, but the genetic susceptibility of MPN is still not well known. Indeed, only few loci are known to have a clear role in the predisposition to this disease. Some studies reported a diagnosis of MPNs and multiple myeloma (MM) in the same patients, but the biological causes are still unclear. We tested the hypothesis that the two diseases share at least partly the same genetic risk loci. In the context of a European multicenter study with 460 cases and 880 controls, we analyzed the effect of the known MM risk loci, individually and in a polygenic risk score (PRS). The most significant result was obtained among patients with chronic myeloid leukemia (CML) for PS0RS1C1-rs2285803, which showed to be associated with an increased risk (OR = 3.28, 95% CI 1.79-6.02, P = .00012, P = .00276 when taking into account multiple testing). Additionally, the PRS showed an association with MPN risk when comparing the last with the first quartile of the PRS (OR = 2.39, 95% CI 1.64-3.48, P = 5.98 × 10-6 ). In conclusion, our results suggest a potential common genetic background between MPN and MM, which needs to be further investigated.

5.
Front Genet ; 11: 975, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33014022

RESUMO

Soluble mesothelin-related peptide (SMRP) is a promising biomarker for malignant pleural mesothelioma (MPM), but several confounding factors can reduce SMRP-based test's accuracy. The identification of these confounders could improve the diagnostic performance of SMRP. In this study, we evaluated the sequence of 1,000 base pairs encompassing the minimal promoter region of the MSLN gene to identify expression quantitative trait loci (eQTL) that can affect SMRP. We assessed the association between four MSLN promoter variants and SMRP levels in a cohort of 72 MPM and 677 non-MPM subjects, and we carried out in vitro assays to investigate their functional role. Our results show that rs2235503 is an eQTL for MSLN associated with increased levels of SMRP in non-MPM subjects. Furthermore, we show that this polymorphic site affects the accuracy of SMRP, highlighting the importance of evaluating the individual's genetic background and giving novel insights to refine SMRP specificity as a diagnostic biomarker.

6.
Blood Cancer J ; 10(8): 89, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32873778

RESUMO

Telomere length measured in leukocyte (LTL) has been found to be associated with the risk of developing several cancer types, including myeloproliferative neoplasms (MPNs). LTL is genetically determined by, at least, 11 SNPs previously shown to influence LTL. Their combination in a score has been used as a genetic instrument to measure LTL and evaluate the causative association between LTL and the risk of several cancer types. We tested, for the first time, the "teloscore" in 480 MPN patients and 909 healthy controls in a European multi-center case-control study. We found an increased risk to develop MPNs with longer genetically determined telomeres (OR = 1.82, 95% CI 1.24-2.68, P = 2.21 × 10-3, comparing the highest with the lowest quintile of the teloscore distribution). Analyzing the SNPs individually we confirm the association between TERT-rs2736100-C allele and increased risk of developing MPNs and we report a novel association of the OBFC1-rs9420907-C variant with higher MPN risk (ORallelic = 1.43; 95% CI 1.15-1.77; P = 1.35 × 10-3). Consistently with the results obtained with the teloscore, both risk alleles are also associated with longer LTL. In conclusion, our results suggest that genetically determined longer telomeres could be a risk marker for MPN development.

7.
J Transl Med ; 18(1): 341, 2020 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-32887638

RESUMO

BACKGROUND: Malignant pleural mesothelioma (MPM) is an aggressive neoplasm of the pleura, mainly related to asbestos exposure. As in other solid tumors, malignant cells exhibit high glucose uptake and glycolytic rates with increased lactic acid efflux into the interstitial space. Lactate transport into and out of cells, crucial to maintaining intracellular pH homeostasis and glycolysis, is carried out by monocarboxylate transporters (MCTs) and the chaperone basigin (CD147). We set out to examine the clinical significance of basigin, MCT1 and MCT4 in the context of MPM and to evaluate their expression in relation to the evolution of the disease. METHODS: We used immunohistochemistry to measure the expression of basigin, MCT1 and MCT4 in a cohort of 135 individuals with MPM compared to a series of 15 non-MPM pleura specimens. Moreover, by Kaplan-Meier and Cox analyses we evaluated whether an expression over the average of these markers could be associated with the patients' overall survival (OS). RESULTS: We detected positive staining of basigin, MCT1, and MCT4 in most MPM specimens. In particular, MCT4 was always positive in malignant tissues but undetectable in the 4 normal pleural specimens incorporated within the tissue microarray. This was confirmed in the additional series of 15 normal pleural samples. Moreover, MCT4 expression was significantly associated with reduced OS. CONCLUSION: In this study, the tissue expression of basigin did not prove to be exploitable as a diagnostic or prognostic marker for MPM patients. The expression of MCT1 was not informative either, being tightly correlated with that of basigin. However, the expression of MCT4 showed promise as a diagnostic/therapeutic and prognostic biomarker.

8.
Semin Cancer Biol ; 2020 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-32818625

RESUMO

Pancreatic cancer (PC), particularly its most common form, pancreatic ductal adenocarcinoma (PDAC), is relatively rare but highly lethal. Knowledge about PC risk factors could in the long term contribute to early diagnosis and mortality reduction. We review the current status of research on germline genetic factors for PC risk. Genome-wide association studies (GWAS) successfully identified common loci convincingly associated with PC risk, an endeavor that is still ongoing. The function of only a handful of risk loci has being thoroughly characterized so far. Secondary analyses of existing GWAS data are being used to discover novel loci. GWAS data have also been used to study additional risk factors with a Mendelian randomization approach. Polygenic/multifactorial risk scores show much larger risks than individual variants, but their use for risk stratification in the population is not warranted yet. At the other end of the spectrum of inherited PC risk factors, rare high-penetrance variants co-segregating with the disease have been observed in familial cancer syndromes that include PC, or in families with multiple recurrence of PC alone. Rare variants predicted to have a deleterious effect on function are studied also with a case-control approach, by resequencing candidate genes or whole-exomes/whole-genomes. Telomere length and mitochondrial DNA copy number are useful additional DNA-based markers of PC susceptibility. The role of common variants in prognosis of PC patients has also been explored, albeit with more limited success than risk. Finally, genetics of pancreatic neuroendocrine tumors (PNET), a rarer and heterogeneous form of PC, is still understudied.

9.
Int J Mol Sci ; 21(14)2020 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-32659970

RESUMO

For malignant pleural mesothelioma (MPM) novel therapeutic strategies are urgently needed. In a previous study, we identified 51 putative cancer genes over-expressed in MPM tissues and cell lines. Here, we deepened the study on nine of them (ASS1, EIF4G1, GALNT7, GLUT1, IGF2BP3 (IMP3), ITGA4, RAN, SOD1, and THBS2) to ascertain whether they are truly mesothelial cancer driver genes (CDGs) or genes overexpressed in an adaptive response to the tumoral progression ("passenger genes"). Through a fast siRNA-based screening, we evaluated the consequences of gene depletion on migration, proliferation, colony formation capabilities, and caspase activities of four MPM (Mero-14, Mero-25, IST-Mes2, and NCI-H28) and one SV40-immortalized mesothelial cell line (MeT-5A) as a non-malignant model. The depletion of EIF4G1 and RAN significantly reduced cell proliferation and colony formation and increased caspase activity. In particular, the findings for RAN resemble those observed for other types of cancer. Thus, we evaluated the in vitro effects of importazole (IPZ), a small molecule inhibitor of the interaction between RAN and importin-ß. We showed that IPZ could have effects similar to those observed following RAN gene silencing. We also found that primary cell lines from one out of three MPM patients were sensitive to IPZ. As EIF4G1 and RAN deserve further investigation with additional in vitro and in vivo studies, they emerged as promising CDGs, suggesting that their upregulation could play a role in mesothelial tumorigenesis and aggressiveness. Furthermore, present data propose the molecular pathways dependent on RAN as a putative pharmacological target for MPM patients in the view of a future personalized medicine.

10.
Semin Cancer Biol ; 2020 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-32659257

RESUMO

Immune checkpoint inhibitors (ICIs) have shown unprecedented benefits in various adult cancers, and this success has prompted the exploration of ICI therapy even in childhood malignances. Although the use of ICIs as individual agents has achieved disappointing response rates, combinational therapies are likely to promise better results. However, only a subset of patients experienced prolonged clinical effects, thus suggesting the need to identify robust bio-markers that predict individual clinical response or resistance to ICI therapy as the main challenge. In this review, we focus on how the use of ICIs in adult cancers can be translated into pediatric malignances. We discuss the physiological mechanism of action of each IC, including PD-1, PD-L1 and CTLA-4 and the new emerging ones, LAG-3, TIM-3, TIGIT, B7-H3, BTLA and IDO-1, and evaluate their prognostic value in both adult and childhood tumors. Furthermore, we offer an overview of preclinical models and clinical trials currently under investigation to improve the effectiveness of cancer immunotherapies in these patients. Finally, we outline the main predictive factors that influence the efficacy of ICIs, in order to lay the basis for the development of a pan-cancer immunogenomic model, able to direct young patients towards more specific immunotherapy.

11.
Thyroid ; 30(11): 1579-1588, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32228166

RESUMO

Background: Sporadic medullary thyroid carcinoma (sMTC) is an uncommon neoplasia arising from the calcitonin-producing parafollicular cells of the thyroid. Previous studies evaluated whether single nucleotide polymorphisms (SNPs) within RET (a pivotal proto-oncogene for this disease) are associated with the risk for developing sMTC, but the results are inconclusive. Methods: In this work, we evaluated the association of RET-SNPs c.74-126G>T (rs2565206), p.Gly691Ser (rs1799939, G>A), p.Leu769 = (rs1800861, G>T), p.Ser836 = (rs1800862, C>T), and p.Ser904 = (rs1800863, C>G) (listed in the order of their chromosomal location) with sMTC. This is one of the largest case-control association studies carried out on sMTC, including 585 sMTC cases (negative for germline mutations within RET), 1529 patients affected by sporadic nonmedullary thyroid carcinoma (sNMTC), and 989 healthy controls, from central and southern Italy and collected in the period 2000-2017. Results: sNMTC patients showed similar genotype and allele frequencies compared with healthy controls. On the other hand, among sMTC patients, the T-allele of p.Leu769 = was less frequent (OR = 0.70 [CI 0.58-0.84], p = 1.9 × 10-4) and rare homozygotes TT showed an OR = 0.32 ([CI 0.17-0.60], p = 2.3 × 10-4). Moreover, a statistically significant excess of the haplotype 2 (characterized by the alleles T-G-G-C-C of the listed SNPs) was observed (p = 3.9 × 10-3). The SNPs were not associated with the expression of RET mRNA, that is, they did not exert an effect in cis as quantitative trait locus (cis-eQTL). However, a strong eQTL association was found for p.Leu769 = and the neighboring gene CSGALNACT2 (p = 9.3 × 10-50; effect-size = -0.65), whose function in cancer is unknown. Conclusions: This study shows that specific RET haplotypes, in particular haplotype 2 and the T-allele of p.Leu769 = , are associated with a reduced risk of sMTC in Italians.

12.
Ann Clin Transl Neurol ; 7(4): 584-589, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32216065

RESUMO

Autosomal recessive spastic paraplegia 52 is caused by biallelic mutations in AP4S1 which encodes a subunit of the adaptor protein complex 4 (AP-4). Using next-generation sequencing, we identified three novel unrelated SPG52 patients from a cohort of patients with cerebral palsy. The discovered variants in AP4S1 lead to reduced AP-4 complex formation in patient-derived fibroblasts. To further understand the role of AP4S1 in neuronal development and homeostasis, we engineered the first zebrafish model of AP-4 deficiency using morpholino-mediated knockdown of ap4s1. In this model, we discovered several phenotypes mimicking SPG52, including altered CNS development, locomotor deficits, and abnormal neuronal excitability.

13.
Int J Cancer ; 146(2): 363-372, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31209889

RESUMO

Interindividual differences in DNA repair systems may play a role in modulating the individual risk of developing colorectal cancer. To better ascertain the role of DNA repair gene polymorphisms on colon and rectal cancer risk individually, we evaluated 15,419 single nucleotide polymorphisms (SNPs) within 185 DNA repair genes using GWAS data from the Colon Cancer Family Registry (CCFR) and the Genetics and Epidemiology of Colorectal Cancer Consortium (GECCO), which included 8,178 colon cancer, 2,936 rectum cancer cases and 14,659 controls. Rs1800734 (in MLH1 gene) was associated with colon cancer risk (p-value = 3.5 × 10-6 ) and rs2189517 (in RAD51B) with rectal cancer risk (p-value = 5.7 × 10-6 ). The results had statistical significance close to the Bonferroni corrected p-value of 5.8 × 10-6 . Ninety-four SNPs were significantly associated with colorectal cancer risk after Binomial Sequential Goodness of Fit (BSGoF) procedure and confirmed the relevance of DNA mismatch repair (MMR) and homologous recombination pathways for colon and rectum cancer, respectively. Defects in MMR genes are known to be crucial for familial form of colorectal cancer but our findings suggest that specific genetic variations in MLH1 are important also in the individual predisposition to sporadic colon cancer. Other SNPs associated with the risk of colon cancer (e.g., rs16906252 in MGMT) were found to affect mRNA expression levels in colon transverse and therefore working as possible cis-eQTL suggesting possible mechanisms of carcinogenesis.


Assuntos
Neoplasias do Colo/genética , Reparo do DNA/genética , Predisposição Genética para Doença , Neoplasias Retais/genética , Adulto , Idoso , Variação Biológica da População/genética , Carcinogênese/genética , Estudos de Casos e Controles , Colo/patologia , Neoplasias do Colo/patologia , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Proteínas de Ligação a DNA/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteína 1 Homóloga a MutL/genética , Polimorfismo de Nucleotídeo Único , Neoplasias Retais/patologia , Reto/patologia , Sistema de Registros/estatística & dados numéricos , Medição de Risco , Proteínas Supressoras de Tumor/genética , Adulto Jovem
14.
Fertil Steril ; 112(2): 343-352.e1, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31256999

RESUMO

OBJECTIVE: To investigate whether nucleoporin 210 (GP210, encoded by NUP210 gene) is involved in endometriosis. DESIGN: Immunohistofluorescence analysis for assessing whether GP210 is expressed in endometrial tissues from patients and controls; genotyping and case-control study for assessing the association between rs354476 within NUP210 and risk of endometriosis; in vitro luciferase assay for assessing the functional activity of rs354476. SETTING: University. PATIENT(S): Histologically diagnosed cases (n = 175) of endometriosis: minimal or mild (stage I-II) in 48 cases (28%), moderate (stage III) in 69 cases (39%), and severe (stage IV) in 58 cases (33%). Controls (n = 557) were female blood donors collected at Meyer Hospital of Florence. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): GP210 tissue expression; genotype distribution and risk of endometriosis; in vitro gene expression measurements. RESULT(S): GP210 had positive nuclear immunohistofluorescence staining in endometrial glandular epithelium. Carriers of the variant allele were associated with increased risks: C/T, odds ratio (OR) 1.83, 95% confidence interval (CI) 1.04-3.21; T/T, OR 2.55, 95% CI 1.36-4.80. In vitro, luciferase assay showed that rs354476 is a bona fide target for hsa-miR-125b-5p. CONCLUSION(S): Nucleoporin GP210 is involved in endometriosis. Rs354476 polymorphism affects the regulation of NUP210 gene expression by altering the binding with hsa-miR-125b-5p, a microRNA already known as playing an important role for endometriosis. This provides the rationale for the observed increased risk of endometriosis in carriers of the variant allele.


Assuntos
Endometriose/genética , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Polimorfismo de Nucleotídeo Único , Doenças Uterinas/genética , Adolescente , Adulto , Estudos de Casos e Controles , Endometriose/patologia , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Índice de Gravidade de Doença , Doenças Uterinas/patologia , Adulto Jovem
15.
Front Neurosci ; 13: 1311, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31920481

RESUMO

Hereditary spastic paraplegia (HSP) and hereditary ataxia (HA) are two groups of disorders characterized, respectively, by progressive dysfunction or degeneration of the pyramidal tracts (HSP) and of the Purkinje cells and spinocerebellar tracts (HA). Although HSP and HA are generally shown to have distinct clinical-genetic profiles, in several cases the clinical presentation, the causative genes, and the cellular pathways and mechanisms involved overlap between the two forms. Genetic analyses in humans in combination with in vitro and in vivo studies using model systems have greatly expanded our knowledge of spinocerebellar degenerative disorders. In this review, we focus on the zebrafish (Danio rerio), a vertebrate model widely used in biomedical research since its overall nervous system organization is similar to that of humans. A critical analysis of the literature suggests that zebrafish could serve as a powerful experimental tool for molecular and genetic dissection of both HA and HSP. The zebrafish, found to be very useful for demonstrating the causal relationship between defect and mutation, also offers a useful platform to exploit for the development of therapies.

16.
Oncogene ; 38(8): 1355-1366, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30237439

RESUMO

BRAFV600E is a mutant Ser-Thr protein kinase that plays a crucial role in many types of cancer, including melanoma. Despite several aspects of BRAFV600E biology have been already elucidated, the proteins that regulate its expression and activity remain largely unknown, hampering our capacity to control its unrestrained effects. Here, we propose yeast Saccharomyces cerevisiae as a model system that can be used to achieve a better understanding of the regulation of human BRAFV600E.By showing that in osmotic stress conditions hBRAFV600E can rescue the growth of strains carrying a double or triple deletion in MAPKKK belonging to the HOG pathway, we demonstrate that this oncogenic kinase is active in yeast even if it does not have an ortholog. Moreover, we report that, in the yeast ptp3∆ptc1∆ strain that is deleted in the genes encoding for two phosphatases responsible for Hog1 de-phoshorylation, hBRAFV600E mimics the toxicity observed in the presence of constitutive Hog1 activation. Finally, we exploit such a toxicity to perform a functional screening of a human cDNA library, looking for cDNAs able to rescue yeast growth. In this way, we identify SMIM10, a mitochondrial protein that in melanoma cells selectively downregulates BRAFV600E RNA and protein levels, by acting indirectly at the post-transcriptional level. Upon SMIM10 overexpression, BRAFV600E melanoma cells show disrupted mitochondrial structure/function and undergo senescence. They also show decreased ability to proliferate and form colonies, as well as increased sensitivity to the BRAF inhibitor vemurafenib. Interestingly, the analysis of TCGA melanoma samples indicates that patients with higher SMIM10 levels have a better prognosis. Therefore, these data suggest that SMIM10 exerts an oncosuppressive role in melanoma cells.Taken together, our results unveil the potential of S. cerevisiae to study hBRAFV600E, to populate the network of its functional interactors and, in doing so, to uncover new cancer-associated genes with therapeutic potential.


Assuntos
Sistema de Sinalização das MAP Quinases/genética , Melanoma/genética , Proteínas de Membrana/metabolismo , Proteínas Mitocondriais/metabolismo , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas de Saccharomyces cerevisiae/genética , Animais , Linhagem Celular Tumoral , Biblioteca Gênica , Humanos , Melanoma/tratamento farmacológico , Melanoma/patologia , Proteínas de Membrana/genética , Proteínas Mitocondriais/genética , Mutação , Inibidores de Proteínas Quinases/farmacologia , Saccharomyces cerevisiae/genética
17.
Front Neurol ; 9: 981, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30564185

RESUMO

Hereditary spastic paraplegia (HSP) refers to a group of genetically heterogeneous neurodegenerative motor neuron disorders characterized by progressive age-dependent loss of corticospinal motor tract function, lower limb spasticity, and weakness. Recent clinical use of next generation sequencing (NGS) methodologies suggests that they facilitate the diagnostic approach to HSP, but the power of NGS as a first-tier diagnostic procedure is unclear. The larger-than-expected genetic heterogeneity-there are over 80 potential disease-associated genes-and frequent overlap with other clinical conditions affecting the motor system make a molecular diagnosis in HSP cumbersome and time consuming. In a single-center, cross-sectional study, spanning 4 years, 239 subjects with a clinical diagnosis of HSP underwent molecular screening of a large set of genes, using two different customized NGS panels. The latest version of our targeted sequencing panel (SpastiSure3.0) comprises 118 genes known to be associated with HSP. Using an in-house validated bioinformatics pipeline and several in silico tools to predict mutation pathogenicity, we obtained a positive diagnostic yield of 29% (70/239), whereas variants of unknown significance (VUS) were found in 86 patients (36%), and 83 cases remained unsolved. This study is among the largest screenings of consecutive HSP index cases enrolled in real-life clinical-diagnostic settings. Its results corroborate NGS as a modern, first-step procedure for molecular diagnosis of HSP. It also disclosed a significant number of new mutations in ultra-rare genes, expanding the clinical spectrum, and genetic landscape of HSP, at least in Italy.

19.
Arch Toxicol ; 92(6): 2137-2140, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29748789

RESUMO

In a recent study, we demonstrated that the variant allele of rs2480258 within intron VIII of CYP2E1 is associated with reduced levels of mRNA, protein, and enzyme activity. CYP2E1 is the most important enzyme in the metabolism of acrylamide (AA) by operating its oxidation into glycidamide (GA). AA occurs in food, is neurotoxic and classified as a probable human carcinogen. The goal of the present study was to further assess the role of rs2480258 by measuring the rate of AA > GA biotransformation in vivo. In blood samples from a cohort of 120 volunteers, the internal doses of AA and GA were assessed by AA and GA adducts to hemoglobin (Hb) measured by mass spectrometry. The rate of biotransformation was assessed by calculating the GA-Hb/AA-Hb ratio. To maximize the statistical power, 60 TT was compared to 60 CC-homozygotes and the results showed that TT homozygotes had a statistically significant reduced rate of biotransformation. Present results reinforced the notion that T-allele of rs2480258 is a marker of low functional activity of CYP2E1. Moreover, we studied the role of polymorphisms (SNPs) within glutathione-S-transferases (GSTs) enzymes and epoxide hydrolase (EPHX), verifying previous findings that SNPs within GSTs and EPHX influence the metabolism rate.


Assuntos
Acrilamida/metabolismo , Citocromo P-450 CYP2E1/genética , Compostos de Epóxi/metabolismo , Polimorfismo de Nucleotídeo Único , Acrilamida/sangue , Adulto , Biotransformação , Citocromo P-450 CYP2E1/metabolismo , Compostos de Epóxi/sangue , Feminino , Frequência do Gene , Genótipo , Voluntários Saudáveis , Humanos , Masculino
20.
J Thorac Dis ; 10(Suppl 2): S246-S252, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29507792

RESUMO

Malignant pleural mesothelioma (MPM) is a cancer of the pleural cavity whose main risk factor is exposure to asbestos. However, it has been shown that only a minority of exposed people develops MPM. In fact, the incidence among professionally exposed workers was shown to vary between 0.5% and 18.0%. Various hints suggested that other important cofactors could play a role, in particular the genetic susceptibility. Impressive is the case of Cappadocians families exposed to erionite and affected by an "epidemic" of MPM with about half of the inhabitants dying for the disease. However, no results for a "Cappadocia" gene of susceptibility to MPM have been obtained yet and more studies are needed. Among asbestos-exposed workers, several studies reported familial cases of MPM, suggesting that heredity could be important in the tumor development. However, large studies on familial clusters showed only weak increased risks that could be attributable also to indirect exposures in a contaminated household. Moreover, the risk of developing MPM is increased of a limited extent among people exposed to asbestos with a positive history of familial cancers. A particular is represented by carriers of germline mutations within BAP1 gene. In families and in animal models, mutations within BAP1 are strongly predisposing to develop MPM. However, also other types of cancer (such as uveal melanoma) are present, thus BAP1 mutations are considered as responsible for a hereditary form of a multi-cancer syndrome. In any case, among sporadic MPM, the prevalence of germline BAP1 mutations is negligible. Finally, genetic studies highlighted the presence of low-risk susceptibility alleles, such as those within XRCC3, NAT2 or GSTM1. Two different genome-wide association studies could not find positive associations reaching the genome-wide statistical significance threshold, however, both were concordant in showing a weak signal within the SDK1 gene region. Overall, it could be concluded that, as for other types of sporadic cancers, the susceptibility to develop MPM following asbestos exposure is modulated moderately by the individual genetic background. Further studies on larger series could help in a better characterization of more genes predisposing to MPM, being this tumor a rare disease.

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