Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 83
Filtrar
Mais filtros

Bases de dados
Tipo de documento
Intervalo de ano de publicação
1.
Biometrics ; 80(2)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38819308

RESUMO

Multi-gene panel testing allows many cancer susceptibility genes to be tested quickly at a lower cost making such testing accessible to a broader population. Thus, more patients carrying pathogenic germline mutations in various cancer-susceptibility genes are being identified. This creates a great opportunity, as well as an urgent need, to counsel these patients about appropriate risk-reducing management strategies. Counseling hinges on accurate estimates of age-specific risks of developing various cancers associated with mutations in a specific gene, ie, penetrance estimation. We propose a meta-analysis approach based on a Bayesian hierarchical random-effects model to obtain penetrance estimates by integrating studies reporting different types of risk measures (eg, penetrance, relative risk, odds ratio) while accounting for the associated uncertainties. After estimating posterior distributions of the parameters via a Markov chain Monte Carlo algorithm, we estimate penetrance and credible intervals. We investigate the proposed method and compare with an existing approach via simulations based on studies reporting risks for two moderate-risk breast cancer susceptibility genes, ATM and PALB2. Our proposed method is far superior in terms of coverage probability of credible intervals and mean square error of estimates. Finally, we apply our method to estimate the penetrance of breast cancer among carriers of pathogenic mutations in the ATM gene.


Assuntos
Teorema de Bayes , Predisposição Genética para Doença , Penetrância , Humanos , Predisposição Genética para Doença/genética , Proteínas Mutadas de Ataxia Telangiectasia/genética , Neoplasias da Mama/genética , Feminino , Proteína do Grupo de Complementação N da Anemia de Fanconi/genética , Simulação por Computador , Cadeias de Markov , Neoplasias/genética , Neoplasias/epidemiologia , Proteínas Supressoras de Tumor/genética , Medição de Risco/métodos , Medição de Risco/estatística & dados numéricos , Método de Monte Carlo , Metanálise como Assunto , Mutação em Linhagem Germinativa , Modelos Estatísticos
2.
Diabetes ; 73(8): 1361-1371, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38776413

RESUMO

Genetic determinants of interindividual differences in energy expenditure (EE) are largely unknown. Sphingolipids, such as ceramides, have been implicated in the regulation of human EE via mitochondrial uncoupling. In this study, we investigated whether genetic variants within enzymes involved in sphingolipid synthesis and degradation affect EE and insulin-related traits in a cohort of American Indians informative for 24-h EE and glucose disposal rates during a hyperinsulinemic-euglycemic clamp. Association analysis of 10,084 genetic variants within 28 genes involved in sphingolipid pathways identified a missense variant (rs267738, A>C, E115A) in exon 4 of CERS2 that was associated with higher sleeping EE (116 kcal/day) and increased rates of endogenous glucose production during basal (5%) and insulin-stimulated (43%) conditions, both indicators of hepatic insulin resistance. The rs267738 variant did not affect ceramide synthesis in HepG2 cells but resulted in a 30% decrease in basal mitochondrial respiration. In conclusion, we provide evidence that the CERS2 rs267738 missense variant may influence hepatic glucose production and postabsorptive sleeping metabolic rate.


Assuntos
Metabolismo Energético , Indígenas Norte-Americanos , Resistência à Insulina , Fígado , Proteínas de Membrana , Esfingosina N-Aciltransferase , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metabolismo Energético/genética , Técnica Clamp de Glucose , Células Hep G2 , Indígenas Norte-Americanos/genética , Resistência à Insulina/genética , Fígado/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Mutação de Sentido Incorreto , Sono/genética , Sono/fisiologia , Esfingosina N-Aciltransferase/genética , Esfingosina N-Aciltransferase/metabolismo , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
3.
Eur Radiol ; 34(9): 5802-5815, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38308012

RESUMO

OBJECTIVES: To evaluate the methodological quality and diagnostic accuracy of MRI-based radiomic studies predicting O6-methylguanine-DNA methyltransferase (MGMT) promoter methylation status in gliomas. METHODS: PubMed Medline, EMBASE, and Web of Science were searched to identify MRI-based radiomic studies on MGMT methylation in gliomas published until December 31, 2022. Three raters evaluated the study methodological quality with Radiomics Quality Score (RQS, 16 components) and Transparent Reporting of a Multivariable Prediction Model for Individual Prognosis Or Diagnosis (TRIPOD, 22 items) scales. Risk of bias and applicability concerns were assessed with QUADAS-2 tool. A meta-analysis was performed to estimate the pooled area under the curve (AUC) and to assess inter-study heterogeneity. RESULTS: We included 26 studies, published from 2016. The median RQS total score was 8 out of 36 (22%, range 8-44%). Thirteen studies performed external validation. All studies reported AUC or accuracy, but only 4 (15%) performed calibration and decision curve analysis. No studies performed phantom analysis, cost-effectiveness analysis, and prospective validation. The overall TRIPOD adherence score was between 50% and 70% in 16 studies and below 50% in 10 studies. The pooled AUC was 0.78 (95% CI, 0.73-0.83, I2 = 94.1%) with a high inter-study heterogeneity. Studies with external validation and including only WHO-grade IV gliomas had significantly lower AUC values (0.65; 95% CI, 0.57-0.73, p < 0.01). CONCLUSIONS: Study RQS and adherence to TRIPOD guidelines was generally low. Radiomic prediction of MGMT methylation status showed great heterogeneity of results and lower performances in grade IV gliomas, which hinders its current implementation in clinical practice. CLINICAL RELEVANCE STATEMENT: MGMT promoter methylation status appears to be variably correlated with MRI radiomic features; radiomic models are not sufficiently robust to be integrated into clinical practice to accurately predict MGMT promoter methylation status in patients with glioma before surgery. KEY POINTS: • Adherence to the indications of TRIPOD guidelines was generally low, as was RQS total score. • MGMT promoter methylation status prediction with MRI radiomic features provided heterogeneous diagnostic accuracy results across studies. • Studies that included grade IV glioma only and performed external validation had significantly lower diagnostic accuracy than others.


Assuntos
Neoplasias Encefálicas , Metilação de DNA , Metilases de Modificação do DNA , Enzimas Reparadoras do DNA , Glioma , Imageamento por Ressonância Magnética , Regiões Promotoras Genéticas , Proteínas Supressoras de Tumor , Humanos , Glioma/diagnóstico por imagem , Glioma/genética , Enzimas Reparadoras do DNA/genética , Imageamento por Ressonância Magnética/métodos , Metilases de Modificação do DNA/genética , Proteínas Supressoras de Tumor/genética , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/genética , Radiômica
4.
Hum Mol Genet ; 33(5): 426-434, 2024 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-37956408

RESUMO

BACKGROUND: Pathogenic germline variants in BRCA1-Associated Protein 1 (BAP1) cause BAP1 tumor predisposition syndrome (BAP1-TPDS). Carriers run especially a risk of uveal (UM) and cutaneous melanoma, malignant mesothelioma, and clear cell renal carcinoma. Approximately half of increasingly reported BAP1 variants lack accurate classification. Correct interpretation of pathogenicity can improve prognosis of the patients through tumor screening with better understanding of BAP1-TPDS. METHODS: We edited five rare BAP1 variants with differing functional characteristics identified from patients with UM in HAP1 cells using CRISPR-Cas9 and assayed their effect on cell adhesion/spreading (at 4 h) and proliferation (at 48 h), measured as cell index (CI), using xCELLigence real-time analysis system. RESULTS: In BAP1 knockout HAP1 cultures, cell number was half of wild type (WT) cultures at 48 h (p = 0.00021), reaching confluence later, and CI was 78% reduced (p < 0.0001). BAP1-TPDS-associated null variants c.67+1G>T and c.1780_1781insT, and a likely pathogenic missense variant c.281A>G reduced adhesion (all p ≤ 0.015) and proliferation by 74%-83% (all p ≤ 0.032). Another likely pathogenic missense variant c.680G>A reduced both by at least 50% (all p ≤ 0.032), whereas cells edited with likely benign one c.1526C>T grew similarly to WT. CONCLUSIONS: BAP1 is essential for optimal fitness of HAP1 cells. Pathogenic and likely pathogenic BAP1 variants reduced cell fitness, reflected in adhesion/spreading and proliferation properties. Further, moderate effects were quantifiable. Variant modelling in HAP1 with CRISPR-Cas9 enabled functional analysis of coding and non-coding region variants in an endogenous expression system.


Assuntos
Neoplasias Renais , Melanoma , Neoplasias Cutâneas , Neoplasias Uveais , Humanos , Melanoma/patologia , Virulência , Predisposição Genética para Doença , Mutação em Linhagem Germinativa/genética , Ubiquitina Tiolesterase/genética , Ubiquitina Tiolesterase/metabolismo , Proteínas Supressoras de Tumor/genética
5.
Zhonghua Yi Xue Za Zhi ; 103(7): 526-529, 2023 Feb 21.
Artigo em Chinês | MEDLINE | ID: mdl-36800777

RESUMO

The data of 1 268 newly diagnosed gliomas from the Fourth Ward of Neurosurgery Department of Beijing Tiantan Hospital between April 2013 and March 2022 were retrospectively analyzed. Based on postoperative pathology, the gliomas were divided into groups: oligodendrogliomas (n=308), astrocytomas (n=337) and glioblastomas (n=623). According to the O6-methylguanine-DNA methyl transferase (MGMT) promoter status defined by the 12% of best cut-off value in previous research results, patients were divided into methylation group (n=763) and non-methylation group (n=505). Methylation level [M (Q1, Q3)] in patients with glioblastoma, astrocytoma and oligodendroglioma was 6% (2%, 24%), 17% (10%, 28%) and 29% (19%, 40%), respectively (P<0.001). Compared with non-methylation patients, the progression-free survival (PFS) and overall survival (OS) of glioblastomas patients with methylation of MGMT promoter demonstrated more favorable prognosis [M (Q1, Q3)]) of PFS: 14.0 (6.0, 36.0) months vs 8.0 (4.0, 15.0) months, P<0.001; M (Q1, Q3) of OS: 29.0 (17.0, 60.5) months vs 16.0 (11.0, 26.5) months, P<0.001]. In astrocytomas patients, the PFS was much longer for those with methylation [the median PFS of patients with methylation was not observed at the end of follow-up, but those without methylation showed a median PFS of 46.0 (29.0, 52.0) months] (P=0.001). However, no statistically significant difference was observed in OS [the median OS of patients with methylation was not observed at the end of follow-up, but those without methylation had a median OS of 62.0 (46.0, 98.0) months] (P=0.085). In oligodendrogliomas patients, no statistically significant differences of PFS and OS were observed between patients with methylation and those without methylation. MGMT promoter status was a related factor affecting PFS and OS in glioblastomas (PFS: HR=0.534,95%CI: 0.426-0.668, P<0.001; OS: HR=0.451, 95%CI: 0.353-0.576, P<0.001). Moreover, MGMT promoter status was also a related factor affecting PFS in astrocytomas (HR=0.462, 95%CI: 0.221-0.966, P=0.040), but not for OS (HR=0.664, 95%CI: 0.259-1.690, P=0.389). The methylation level of MGMT promoter differed substantially in different types of gliomas, and the status of MGMT promoter profoundly affected the prognosis of glioblastomas.


Assuntos
Astrocitoma , Glioblastoma , Glioma , Oligodendroglioma , Humanos , Estudos Retrospectivos , Glioma/genética , Prognóstico , Metilases de Modificação do DNA/genética , Proteínas Supressoras de Tumor/genética , Enzimas Reparadoras do DNA/genética
6.
Adv Protein Chem Struct Biol ; 130: 375-397, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35534113

RESUMO

Breast cancer type 1 susceptibility protein (BRCA1) is closely related to the BRCA2 (breast cancer type 2 susceptibility protein) and BARD1 (BRCA1-associated RING domain-1) proteins. The homodimers were formed through their RING fingers; however they form more compact heterodimers preferentially, influencing BRCA1 residues 1-109 and BARD1 residues 26-119. We implemented an integrative computational pipeline to screen all the mutations in BRCA1 and identify the most significant mutations influencing the Protein-Protein Interactions (PPI) in the BRCA1-BARD1 protein complex. The amino acids involved in the PPI regions were identified from the PDBsum database with the PDB ID: 1JM7. We screened 2118 missense mutations in BRCA1 and none in BARD1 for pathogenicity and stability and analyzed the amino acid sequences for conserved residues. We identified the most significant mutations from these screenings as V11G, M18K, L22S, and T97R positioned in the PPI regions of the BRCA1-BARD1 protein complex. We further performed protein-protein docking using the ZDOCK server. The native protein-protein complex showed the highest binding score of 2118.613, and the V11G mutant protein complex showed the least binding score of 1992.949. The other three mutation protein complexes had binding scores between the native and V11G protein complexes. Finally, a molecular dynamics simulation study using GROMACS was performed to comprehend changes in the BRCA1-BARD1 complex's binding pattern due to the mutation. From the analysis, we observed the highest deviation with lowest compactness and a decrease in the intramolecular h-bonds in the BRCA1-BARD1 protein complex with the V11G mutation compared to the native complex or the complexes with other mutations.


Assuntos
Proteína BRCA1 , Neoplasias da Mama , Sequência de Aminoácidos , Proteína BRCA1/química , Proteína BRCA1/genética , Proteína BRCA1/metabolismo , Neoplasias da Mama/genética , Feminino , Humanos , Mutação , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina-Proteína Ligases/química , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
7.
Pharmacol Ther ; 232: 108009, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34619284

RESUMO

The breast cancer type 1 susceptibility protein (BRCA1) and its partner - the BRCA1-associated RING domain protein 1 (BARD1) - are key players in a plethora of fundamental biological functions including, among others, DNA repair, replication fork protection, cell cycle progression, telomere maintenance, chromatin remodeling, apoptosis and tumor suppression. However, mutations in their encoding genes transform them into dangerous threats, and substantially increase the risk of developing cancer and other malignancies during the lifetime of the affected individuals. Understanding how BRCA1 and BARD1 perform their biological activities therefore not only provides a powerful mean to prevent such fatal occurrences but can also pave the way to the development of new targeted therapeutics. Thus, through this review work we aim at presenting the major efforts focused on the functional characterization and structural insights of BRCA1 and BARD1, per se and in combination with all their principal mediators and regulators, and on the multifaceted roles these proteins play in the maintenance of human genome integrity.


Assuntos
Proteína BRCA1 , Neoplasias , Proteína BRCA1/genética , Proteína BRCA1/metabolismo , Reparo do DNA , Bolsas de Estudo , Humanos , Neoplasias/genética , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
8.
JAMA Netw Open ; 4(11): e2132615, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34767027

RESUMO

Importance: In BAP1 tumor predisposition syndrome, clear cell renal cell carcinoma (RCC) is frequently associated with melanoma and/or mesothelioma, while germline MITF p.E318K alterations are being increasingly reported in melanoma/RCC. Limited data exist on the co-occurrence of melanoma and/or mesothelioma with renal neoplasia and the prevalence of associated germline alterations. Objective: To assess the frequency of melanoma and/or mesothelioma co-occurring with renal neoplasia using our institutional nephrectomy registry and to determine the prevalence of BAP1 and MITF alterations within this cohort. Design, Setting, and Participants: In this genetic association study, medical records from 8295 patients from 1970 to 2018, renal neoplasia co-occurring with melanoma and/or mesothelioma within a single institutional nephrectomy registry was reevaluated based on contemporary histopathologic criteria and the medical records were reviewed. Data were analyzed from September 2019 to May 2021. Main Outcomes and Measures: Identified cases were screened for BAP1 loss using immunohistochemistry; while patients with melanoma and clear cell RCC were screened for MITF p.E318K alterations. Tumors from patients with potential germline alterations were analyzed with comprehensive molecular profiling using a 514-gene next generation sequencing panel. Results: Of a total of 8295 patients, 93 (1.1%; 95% CI, 0.9%-1.4%) had melanoma and/or mesothelioma co-occurring with renal neoplasia (cutaneous melanoma, n = 76; uveal melanoma, n = 11; mesothelioma, n = 6). A total of 69 (74.2%) were male; 24 (25.8%) were female; median age at diagnosis of renal neoplasia was 63 years (IQR, 58-70 years) and the median duration of follow-up was 8.5 years (IQR, 5.0-14.6 years). Two patients with clear cell RCC had germline BAP1 alterations in the setting of cutaneous melanoma and mesothelioma. Two patients with hybrid oncocytic tumors had biallelic inactivation of FLCN in a setting of Birt-Hogg-Dubé (BHD) syndrome associated with uveal melanoma and mesothelioma. Tumor-only screening of clear cell RCC associated with cutaneous (n = 53) and uveal melanoma (n = 6) led to the identification of 1 patient with a likely germline MITF p.E318K alteration. After excluding benign renal neoplasia (such as oncocytoma and angiomyolipoma), alterations of BAP1, FLCN, and MITF were identified in 5 of 81 patients (6.2%) with melanoma and/or mesothelioma and renal neoplasia. In contrast to hybrid oncocytic tumors in BHD, no unique genotype-phenotype correlations were seen for clear cell RCC with pathogenic BAP1/ MITF alterations and VHL loss of function variants. Four of 5 cases (80%) met current National Comprehensive Cancer Network criteria for germline testing based on a combination of age, multifocality, histologic findings, and family history. Conclusions and Relevance: In this genetic association study, findings support the continued use of these National Comprehensive Cancer Network criteria and suggest more stringent screening may be warranted in this patient population.


Assuntos
Predisposição Genética para Doença/epidemiologia , Neoplasias Renais/genética , Melanoma/genética , Mesotelioma/genética , Fator de Transcrição Associado à Microftalmia/genética , Proteínas Supressoras de Tumor/genética , Ubiquitina Tiolesterase/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Mutação em Linhagem Germinativa , Humanos , Neoplasias Renais/complicações , Neoplasias Renais/epidemiologia , Neoplasias Renais/patologia , Masculino , Melanoma/complicações , Melanoma/epidemiologia , Melanoma/patologia , Mesotelioma/complicações , Mesotelioma/epidemiologia , Mesotelioma/patologia , Pessoa de Meia-Idade , Minnesota/epidemiologia , Proteínas Proto-Oncogênicas , Sistema de Registros
9.
J Cell Mol Med ; 25(14): 6652-6663, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34080290

RESUMO

Lung cancer is a very aggressive cancer characterized with molecular heterogeneities in different subtypes, including lung adenocarcinoma and lung squamous cell carcinoma. However, few related molecular signatures have been established for the treatment of lung cancer subtypes. Polo-like kinase (PLK) family is a crucial regulator during cell division. Aberrant genetic and epigenetic alteration of PLK members plays a controversial role among different cancers. In this study, we performed an analysis of transcriptional and protein expression to identify overexpressed PLK1/4 and under-expressed PLK2/3 in lung cancer subtypes. We then analysed biological function of PLKs and related genes. Besides, we estimated a correlation of PLKs with patient's genders and TP53 mutation in lung cancer. Higher PLK1/4 expression was significantly associated with male patient and TP53 mutant status, separately. Moreover, we carried out a methylation profile analysis including methylation level, DNA methyltransferases correlation and survival analysis of global methylation. Global methylation survival analysis showed that prognostic value of PLK1/2/4 methylation remained the same significant trend between two lung cancer subtypes, whereas prognostic value of PLK3 methylation lacked consistency. Taken together, these results provided instructive insights into a comprehensive evaluation for advanced therapeutic strategy based on epigenetic evidences.


Assuntos
Adenocarcinoma de Pulmão/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Proteínas de Ciclo Celular/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Supressoras de Tumor/genética , Adenocarcinoma de Pulmão/diagnóstico , Adenocarcinoma de Pulmão/patologia , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/patologia , Metilação de DNA/genética , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Masculino , Prognóstico , Proteína Supressora de Tumor p53/genética , Quinase 1 Polo-Like
11.
BMC Urol ; 21(1): 36, 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33691672

RESUMO

BACKGROUND: WW Domain Containing Oxidoreductase (WWOX) belongs to the unusual tumor suppressors, whose molecular function is not fully understood in bladder cancer, especially regarding interaction with Activator Protein 2 (AP-2) α/γ transcription factors. Thus, using lentiviral systems we created an in vitro model overexpressing or downregulating WWOX in CAL-29 cell line to assess invasiveness pathways. Surprisingly, while WWOX overexpression was accompanied with increased expression of both AP-2 factors, its downregulation only affected AP-2α level but not AP-2γ which remained high. METHODS: Using cellular models and unpaired t-test or Wilcoxon test, we investigated significant changes in biological processes: clonogenicity, extracellular matrix adhesion, metalloproteinases activity, 3D culture growth, proliferation, mitochondrial redox potential and invasiveness. Relative gene expression acquired through Real-Time qPCR has been analyzed by Welch's t-test. Additionally, using oncoprint analysis we distinguished groups for bioinformatics analyzes in order to perform a follow-up of in vitro experiments. RESULTS: Downregulation of WWOX in bladder cancer cell line intensified ability of single cell to grow into colony, mitochondrial redox potential and proliferation rate. Moreover, these cells shown elevated pro-MMP-2/9 activity but reduced adhesion to collagen I or laminin I, as well as distinct 3D culture growth. Through global in silico profiling we determined that WWOX alters disease-free survival of bladder cancer patients and modulates vital processes through AP-2 downstream effectors. CONCLUSIONS: Our research indicates that WWOX possesses tumor suppressor properties in bladder cancer but consecutive examination is required to entirely understand the contribution of AP-2γ or AP-2α.


Assuntos
Regulação Neoplásica da Expressão Gênica , Fator de Transcrição AP-2/fisiologia , Proteínas Supressoras de Tumor/genética , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia , Oxidorredutase com Domínios WW/genética , Linhagem Celular Tumoral , Simulação por Computador , Humanos , Invasividade Neoplásica/genética
12.
JCO Clin Cancer Inform ; 5: 143-154, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33513031

RESUMO

PURPOSE: Pathogenic BAP1 germline variants cause a tumor-predisposition syndrome (BAP1-TPDS) linked to uveal melanoma, mesothelioma, cutaneous melanoma, and renal cell carcinoma. Surveillance of carriers of pathogenic BAP1 variants provides an opportunity for early tumor detection; however, there are no evidence-based guidelines for management of BAP1-TPDS, nor health economic evaluation; this study aims to provide this evidence. METHODS: We created a Markov microsimulation health state transition model of BAP1 germline carriers to predict if active surveillance for the four main tumors influences survival and improves associated economic costs with a time horizon of 100 years from the perspective of the healthcare system (N = 10,000). Model inputs were derived from data published by the BAP1 Interest Group Consortium and other studies. Management and healthcare costs were extracted from Australian costing schedules (final figures converted to US dollars [USD]), and outcomes compared for individuals receiving surveillance with those in a nonsurveillance arm. Robustness was evaluated on 10,000 iterations of a 100-sample random sampling of the model output. RESULTS: On average, surveillance of BAP1 carriers increased survival by 4.9 years at an additional cost of $6,197 USD for the healthcare system including surveillance costs ($1,265 USD per life year gained). The nonsurveillance arm had more diagnosed late tumors (62.8% v 10.7%) and a higher rate of BAP1-related deaths (50.2% v 35.4%; a 29.5% increase). The model was cost-effective under all sensitivity analyses. Our secondary robustness analysis estimated that 99.86% of 100-sample iterations were cost-effective and 19.67% of these were cost-saving. CONCLUSION: It is recommended that carriers of BAP1 germline variants are identified and undertake active surveillance, as this model suggests that this could improve survival and be cost-effective for the healthcare system.


Assuntos
Melanoma , Neoplasias Cutâneas , Proteínas Supressoras de Tumor , Ubiquitina Tiolesterase , Austrália , Análise Custo-Benefício , Mutação em Linhagem Germinativa , Humanos , Melanoma/diagnóstico , Neoplasias Cutâneas/diagnóstico , Proteínas Supressoras de Tumor/genética , Ubiquitina Tiolesterase/genética
13.
Clin Epigenetics ; 12(1): 174, 2020 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-33203454

RESUMO

BACKGROUND: The utility of O6-methylguanine-DNA methyltransferase (MGMT) gene promoter methylation status as a prognostic marker in patients with glioblastoma (GBM) has been established. However, the number of CpG sites that must be methylated to cause transcriptional silencing remains unclear, and no significant consensus exists on the optimal method of assessing MGMT methylation. We developed a new high-performance liquid chromatography (HPLC) method that enables accurate analysis of DNA methylation levels using long PCR products. In the present study, we analyzed the MGMT methylation status of 28 isocitrate dehydrogenase-wild-type GBMs treated with temozolomide using ion-exchange HPLC and set the optimal cutoff values. RESULTS: We designed three primers for separate regions (regions 1-3) that had 21 to 38 CpGs for PCR and validated the MGMT promoter methylation status using frozen samples. There was a strong correlation between HPLC and bisulfite sequencing results (R = 0.794). The optimal cutoff values for MGMT methylation in HPLC were determined to allow differentiation of patient prognosis by receiver operating characteristic curve analysis. The cutoff values were 34.15% for region 1, 8.84% for region 2, and 36.72% for region 3. Kaplan-Meyer curve analysis estimated that the most differentiated prognosis was enabled in the setting of 8.84% methylation of MGMT in region 2. Progression-free survival and overall survival were significantly longer for patients in this setting of region 2 methylation (p = 0.00365 and p = 0.00258, respectively). CONCLUSIONS: The combination of our HPLC method and the original primer setting provides a new standard method for determination of MGMT methylation status in patients with GBM and is useful for refining MGMT-based drug selection.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Glioblastoma/genética , Regiões Promotoras Genéticas/genética , Proteínas Supressoras de Tumor/genética , Idoso , Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Encefálicas/patologia , Ilhas de CpG , Metilação de DNA , Epigenômica , Feminino , Glioblastoma/diagnóstico , Glioblastoma/tratamento farmacológico , Humanos , Masculino , Reação em Cadeia da Polimerase/métodos , Prognóstico , Intervalo Livre de Progressão , Proteínas Repressoras/genética , Temozolomida/uso terapêutico
15.
J Neurol Sci ; 418: 117102, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32866816

RESUMO

Temozolomide (TMZ) therapy is the standard of care for patients with glioblastoma (GBM). Clinical studies have shown that elevated levels of DNA repair protein O (6)-methylguanine-DNA methyltransferase (MGMT) or deficiency/defect of DNA mismatch repair (MMR) genes is associated with TMZ resistance in some, but not all, GBM tumors. Another reason for GBM treatment failure is signal redundancy due to coactivation of several functionally linked receptor tyrosine kinases (RTKs), including anaplastic lymphoma kinase (ALK) and c-Met (hepatocyte growth factor receptor). As such, these tyrosine kinases serve as potential targets for GBM therapy. Thus, we tested two novel drugs: INC280 (Capmatinib: a highly selective c-Met receptor tyrosine kinase-RTK inhibitor) and LDK378 (Ceritinib: a highly selective anaplastic lymphoma kinase-ALK inhibitor), aiming to overcome TMZ resistance in MGMT-unmethylated GBM cells in in vitro cell culture models. Treatments were examined using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, caspase-3 assay and western blot analysis. Results obtained from our experiments demonstrated that preconditioning with INC280 and LDK378 drugs exhibit increased MMR protein expression, specifically MMR protein MLH1 (MutL Homolog 1) and MSH6 (MutS Homolog 6) and sensitized TMZ in MGMT-unmethylated GBM cells via suppression of ALK and c-Met expression. INC280 and LDK378 plus TMZ also induced apoptosis by modulating downstream signaling of PI3K/AKT/STAT3. Taken together, this data indicates that co-inhibition of ALK and c-MET can enhance growth inhibitory effects in MGMT-unmethylated cells and enhance TMZ sensitivity in-vitro, suggesting c-Met inhibitors combined with ALK-targeting provide a therapeutic benefit in MGMT-unmethylated GBM patients.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Preparações Farmacêuticas , Antineoplásicos Alquilantes/farmacologia , Antineoplásicos Alquilantes/uso terapêutico , Benzamidas , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Linhagem Celular Tumoral , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Resistencia a Medicamentos Antineoplásicos/genética , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Humanos , Imidazóis , Fosfatidilinositol 3-Quinases , Pirimidinas , Sulfonas , Temozolomida/farmacologia , Temozolomida/uso terapêutico , Triazinas , Proteínas Supressoras de Tumor/genética
16.
Clin Epigenetics ; 12(1): 131, 2020 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-32859265

RESUMO

BACKGROUND: The number of tumor suppressor genes for which germline mutations have been linked to cancer risk is steadily increasing. However, while recent reports have linked constitutional normal tissue promoter methylation of BRCA1 and MLH1 to ovarian and colon cancer risk, the role of epigenetic alterations as cancer risk factors remains largely unknown, presenting an important area for future research. Currently, we lack fast and sensitive methods for assessment of promoter methylation status across known tumor suppressor genes. RESULTS: In this paper, we present a novel NGS-based approach assessing promoter methylation status across a large panel of defined tumor suppressor genes to base-pair resolution. The method omits the limitations related to commonly used array-approaches. Our panel includes 565 target regions covering the promoters of 283 defined tumor suppressors, selected by pre-specified criteria, and was applied for rapid targeted methylation-specific NGS. The feasibility of the method was assessed by analyzing normal tissue DNA (white blood cells, WBC) samples from 34 healthy postmenopausal women and by performing preliminary assessment of the methylation landscape of tumor suppressors in these individuals. The mean target coverage was 189.6x providing a sensitivity of 0.53%, sufficient for promoter methylation assessment of low-level methylated genes like BRCA1. Within this limited test-set, we detected 206 regions located in the promoters of 149 genes to be differentially methylated (hyper- or hypo-) at > 99% confidence level. Seven target regions in gene promoters (CIITA, RASSF1, CHN1, PDCD1LG2, GSTP1, XPA, and ZNF668) were found to be hyper-methylated in a minority of individuals, with a > 20 percent point difference in mean methylation across the region between individuals. In an exploratory hierarchical clustering analysis, we found that the individuals analyzed may be grouped into two main groups based on their WBC methylation profile across the 283 tumor suppressor gene promoters. CONCLUSIONS: Methylation-specific NGS of our tumor suppressor panel, with detailed assessment of differential methylation in healthy individuals, presents a feasible method for identification of novel epigenetic risk factors for cancer.


Assuntos
Metilação de DNA/genética , Regiões Promotoras Genéticas/genética , Proteínas Supressoras de Tumor/genética , Epigênese Genética/genética , Feminino , Humanos , Pós-Menopausa , Valores de Referência
17.
PLoS One ; 15(8): e0237248, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32790723

RESUMO

Despite enzalutamide's efficacy in delaying the progression of metastatic castration-resistant prostate cancer (CRPC), resistance to this anti-androgen inevitably occurs. Several studies have revealed that the signal transducer and activator of transcription (STAT) 5 plays a role in tumour progression and development of drug resistance such as enzalutamide. Data mining revealed heterogeneous expression of STAT5 in enzalutamide-treated mCRPC patients and enzalutamide-resistant prostate cancer (PCa). Isobologram analysis revealed that the STAT5 inhibitor pimozide combined with enzalutamide has? additive and synergistic inhibitory effects on cell viability in the used models. Functional analysis with siRNA-mediated STAT5 knockdown yielded divergent results. The LNCaP-derived cell line MR49F could be resensitised to enzalutamide by siRNA-mediated STAT5b-knock-down. In contrast, neither STAT5a nor STAT5b knockdown resensitised enzalutamide-resistant LAPC4-EnzaR cells to enzalutamide. In conclusion, our results indicate that STAT5 may be a possible target in a subgroup of enzalutamide-resistant PCa. However, based on the data presented here, a general role of STAT5 in enzalutamide-resistance and its potential as a therapeutic target could not be shown.


Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos , Feniltioidantoína/análogos & derivados , Neoplasias da Próstata/tratamento farmacológico , Fator de Transcrição STAT5/genética , Proteínas Supressoras de Tumor/genética , Benzamidas , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Nitrilas , Feniltioidantoína/farmacologia , Neoplasias da Próstata/genética
18.
Biochim Biophys Acta Mol Basis Dis ; 1866(8): 165822, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32360590

RESUMO

Lung cancer is one of the most common cancer types worldwide and causes more than one million deaths annually. Lung adenocarcinoma (AC) and lung squamous cell cancer (SCC) are two major lung cancer subtypes and have different characteristics in several aspects. Identifying their differentially expressed genes and different gene expression patterns can deepen our understanding of these two subtypes at the transcriptomic level. In this work, we used several machine learning algorithms to investigate the gene expression profiles of lung AC and lung SCC samples retrieved from Gene Expression Omnibus. First, the profiles were analyzed by using a powerful feature selection method, namely, Monte Carlo feature selection. A feature list, ranking all features according to their importance, and some informative features were obtained. Then, the feature list was used in the incremental feature selection method to extract optimal features, which can allow the support vector machine (SVM) to yield the best performance for classifying lung AC and lung SCC samples. Some top genes (CSTA, TP63, SERPINB13, CLCA2, BICD2, PERP, FAT2, BNC1, ATP11B, FAM83B, KRT5, PARD6G, PKP1) were extensively analyzed to prove that they can be differentially expressed genes between lung AC and lung SCC. Meanwhile, a rule learning procedure was applied on informative features to construct the classification rules. These rules provide a clear procedure of classification and show some different gene expression patterns between lung AC and lung SCC.


Assuntos
Adenocarcinoma de Pulmão/genética , Carcinoma de Células Escamosas/genética , Biologia Computacional/métodos , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/genética , Aprendizado de Máquina/estatística & dados numéricos , Adenocarcinoma de Pulmão/diagnóstico , Adenocarcinoma de Pulmão/metabolismo , Adenocarcinoma de Pulmão/patologia , Adenosina Trifosfatases/genética , Adenosina Trifosfatases/metabolismo , Caderinas/genética , Caderinas/metabolismo , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Cistatina A/genética , Cistatina A/metabolismo , Conjuntos de Dados como Assunto , Diagnóstico Diferencial , Perfilação da Expressão Gênica , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Método de Monte Carlo , Serpinas/genética , Serpinas/metabolismo , Terminologia como Assunto , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcriptoma , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
19.
J Mol Diagn ; 22(4): 457-466, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32036091

RESUMO

Pleural effusions are among the first clinical manifestations of malignant pleural mesothelioma (MPM) and often constitute the only available material for diagnosis. Although an MPM diagnosis can be reliable on cytology, the reported sensitivity is low (30% to 75%). Particularly, it can be hard to discriminate epithelioid MPM, the most common histotype, from reactive mesothelial hyperplasia (MH). Currently, BRCA1-associated protein 1 (BAP1) and CDKN2A (p16), evaluated by immunohistochemistry and fluorescent in situ hybridization, respectively, are the most valuable markers to discriminate MPM and MH. Both markers have a high specificity, but their sensitivity is not always satisfying, even when used together. We have recently developed a 117-gene expression panel, based on Nanostring technology, able to differentiate epithelioid MPM from MH pleural tissues better than BAP1 and p16. Herein, we evaluated the efficacy of the same panel on an independent retrospective cohort of 23 MPM and 11 MH pleural effusions (cell blocks and smears). The overall sensitivity and specificity of the panel were equal to 0.9565 and 1, respectively. Moreover, the panel performance was compared with BAP1 and p16 on 25 cell blocks. Sensitivity levels of gene panel, BAP1 alone, p16 alone, and BAP1 plus p16 were 1, 0.5882, 0.4706, and 0.7647, respectively. Specificity was always 1. Although further validation is needed, this gene panel could really facilitate patients' management, allowing a definitive MPM diagnosis directly on pleural effusions.


Assuntos
Mesotelioma Maligno/diagnóstico , Neoplasias Pleurais/diagnóstico , Idoso , Biomarcadores Tumorais , Inibidor p16 de Quinase Dependente de Ciclina/genética , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Citodiagnóstico , Diagnóstico Diferencial , Feminino , Perfilação da Expressão Gênica/métodos , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Masculino , Mesotelioma Maligno/genética , Pessoa de Meia-Idade , Neoplasias Pleurais/genética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina Tiolesterase/genética , Ubiquitina Tiolesterase/metabolismo
20.
World Neurosurg ; 137: e213-e220, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32001415

RESUMO

BACKGROUND: Patients of lower socioeconomic status (SES) may experience barriers to their oncologic care, but current data conflict over whether SES affects the prognosis of patients with glioblastoma (GB). OBJECTIVE: We sought to determine whether SES disparities impaired delivery of neuro-oncologic care and affected the prognosis of GB patients. METHODS: The records of GB patients treated from 2010 to 2014 at a safety-net hospital (SNH) or private hospital (PH), both served by 1 academic medical institution, were retrospectively reviewed and compared. Overall survival (OS) and progression-free survival (PFS) were estimated using the Kaplan-Meier method. RESULTS: A total of 55 SNH and 39 PH GB patients were analyzed with median 11-month follow-up. SNH patients were predominantly Hispanic, low income, enrolled in Medicaid, were less likely to receive radiation (89% vs. 100%), took longer to start radiation (41 vs. 29 days), and were less likely to complete radiation treatment (80% vs. 95%). Concurrent and adjuvant temozolomide use were also lower (85% vs. 94% and 60% vs. 71%, respectively). OS and PFS were not significantly different (15 vs. 16 months and 8 vs. 11 months, respectively). On multivariate analysis, adjuvant chemotherapy and RT completion predicted for better OS, whereas hospital type, income, and insurance did not. CONCLUSION: Although GB patients at our SNH received less adjuvant treatment compared with PH, outcomes were similar. Access to multidisciplinary care staffed by academic physicians may play an important role in overcoming socioeconomic barriers to treatment availability and quality at SNHs.


Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Encefálicas/terapia , Glioblastoma/terapia , Disparidades em Assistência à Saúde/estatística & dados numéricos , Hospitais Privados , Procedimentos Neurocirúrgicos , Provedores de Redes de Segurança , Temozolomida/uso terapêutico , Tempo para o Tratamento/estatística & dados numéricos , Idoso , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Quimiorradioterapia Adjuvante/estatística & dados numéricos , Quimioterapia Adjuvante/estatística & dados numéricos , Estudos de Coortes , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Etnicidade/estatística & dados numéricos , Feminino , Glioblastoma/genética , Glioblastoma/patologia , Humanos , Isocitrato Desidrogenase/genética , Estimativa de Kaplan-Meier , Masculino , Medicaid , Pessoa de Meia-Idade , Pobreza/estatística & dados numéricos , Intervalo Livre de Progressão , Radioterapia Adjuvante/estatística & dados numéricos , Estudos Retrospectivos , Classe Social , Padrão de Cuidado , Taxa de Sobrevida , Carga Tumoral , Proteínas Supressoras de Tumor/genética , Estados Unidos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA