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1.
Hum Mutat ; 42(3): 290-299, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33326660

RESUMEN

The current study aimed to identify new breast and/or ovarian cancer predisposition genes. For that, whole-exome sequencing (WES) was performed in the germline DNA of 52 non-BRCA1/BRCA2/TP53 mutation carrier women at high-risk for hereditary breast and ovarian cancer (HBOC). All variants were classified using information from population and disease specific databases, in silico prediction tools and the American College of Medical Genetics and Genomics (ACMG) criteria. Loss of heterozygosity (LOH) of tumor samples and segregation analyses were performed whenever possible. The variants identified were investigated in a second, independent cohort of 17 BC cases. Pathogenic/Likely Pathogenic variants were identified in known cancer genes such as CHEK2, MUTYH, PMS2, and RAD51C. Rare and potentially pathogenic variants were identified in DNA repair genes (FAN1, POLQ, and RAD54L) and other cancer-related genes such as DROSHA and SLC34A2. Interestingly, the variant c.149T>G in the FAN1 gene was identified in two unrelated families, and exhibited LOH in the tumor tissue of one of them. In conclusion, this is the largest Brazilian WES study involving families at high-risk for HBOC which has brought novel insights into the role of potentially new genetic risk factors for hereditary breast and ovarian cancer.


Asunto(s)
Neoplasias de la Mama , Síndrome de Cáncer de Mama y Ovario Hereditario , Neoplasias Ováricas , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias de la Mama/patología , Femenino , Genes BRCA2 , Predisposición Genética a la Enfermedad , Mutación de Línea Germinal , Síndrome de Cáncer de Mama y Ovario Hereditario/genética , Humanos , Pérdida de Heterocigocidad , Mutación , Neoplasias Ováricas/genética , Secuenciación del Exoma
2.
J Pathol ; 251(1): 87-99, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32154590

RESUMEN

The oncogene brachyury (TBXT) is a T-box transcription factor that is overexpressed in multiple solid tumors and is associated with tumor aggressiveness and poor patient prognosis. Gliomas comprise the most common and aggressive group of brain tumors, and at the present time the functional and clinical impact of brachyury expression has not been investigated previously in these neoplasms. Brachyury expression (mRNA and protein) was assessed in normal brain (n = 67), glioma tissues (n = 716) and cell lines (n = 42), and further in silico studies were undertaken using genomic databases totaling 3115 samples. Our glioma samples were analyzed for copy number (n = 372), promoter methylation status (n = 170), and mutation status (n = 1569 tissues and n = 52 cell lines) of the brachyury gene. The prognostic impact of brachyury expression was studied in 1524 glioma patient tumors. The functional impact of brachyury on glioma proliferation, viability, and cell death was evaluated both in vitro and in vivo. Brachyury was expressed in the normal brain, and significantly downregulated in glioma tissues. Loss of brachyury was associated with tumor aggressiveness and poor survival in glioma patients. Downregulation of brachyury was not associated with gene deletion, promoter methylation, or inactivating point mutations. Brachyury re-expression in glioma cells was found to decrease glioma tumorigenesis by induction of autophagy. These data strongly suggest that brachyury behaves as a tumor suppressor gene in gliomas by modulating autophagy. It is important to note that brachyury constitutes an independent positive biomarker of patient prognosis. Our findings indicate that the role of brachyury in tumorigenesis may be tissue-dependent and demands additional investigation to guide rational interventions. © 2020 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Asunto(s)
Neoplasias Encefálicas/patología , Proteínas Fetales/metabolismo , Regulación Neoplásica de la Expresión Génica , Glioma/genética , Proteínas de Dominio T Box/metabolismo , Animales , Biomarcadores de Tumor/genética , Neoplasias Encefálicas/genética , Línea Celular Tumoral , Proteínas Fetales/genética , Genes Supresores de Tumor/fisiología , Glioma/patología , Humanos , Ratones , Pronóstico , Regiones Promotoras Genéticas , Proteínas de Dominio T Box/genética , Factores de Transcripción/metabolismo
3.
Int J Cancer ; 139(2): 414-23, 2016 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-26914704

RESUMEN

Human hotspot TERT promoter (TERTp) mutations have been reported in a wide range of tumours. Several studies have shown that TERTp mutations are associated with clinicopathological features; in some instances, TERTp mutations were considered as biomarkers of poor prognosis. The rs2853669 SNP, located in the TERT promoter region, was reported to modulate the increased TERT expression levels induced by the recurrent somatic mutations. In this study we aimed to determine the frequency and prognostic value of TERTp mutations and TERT rs2853669 SNP in 504 gliomas from Portuguese and Brazilian patients. TERTp mutations were detected in 47.8% of gliomas (216/452). Glioblastomas (GBM) exhibited the highest frequency of TERTp mutations (66.9%); in this glioma subtype, we found a significant association between TERTp mutations and poor prognosis, regardless of the population. Moreover, in a multivariate analysis, TERTp mutations were the only independent prognostic factor. Our data also showed that the poor prognosis conferred by TERTp mutations was restricted to GBM patients carrying the rs2853669 A allele and not in those carrying the G allele. In conclusion, the presence of TERTp mutations was associated with worse prognosis in GBM patients, although such association depended on the status of the rs2853669 SNP. The status of the rs2853669 SNP should be taken in consideration when assessing the prognostic value of TERTp mutations in GBM patients. TERTp mutations and the rs2853669 SNP can be used in the future as biomarkers of glioma prognosis.


Asunto(s)
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/mortalidad , Glioblastoma/genética , Glioblastoma/mortalidad , Mutación , Polimorfismo de Nucleótido Simple , Regiones Promotoras Genéticas , Telomerasa/genética , Adolescente , Adulto , Anciano , Alelos , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/terapia , Niño , Preescolar , Femenino , Genotipo , Glioblastoma/patología , Glioblastoma/terapia , Humanos , Lactante , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Pronóstico , Adulto Joven
4.
Artículo en Inglés | MEDLINE | ID: mdl-37608030

RESUMEN

PURPOSE: Evaluate overall survival (OS), RAS, BRAF, and MSI frequencies in patients with metastatic colorectal cancer (mCRC), refractory to chemotherapy, and finally treated with cetuximab. METHODS: A retrospective cohort study to evaluate 211 mCRC patients with wild-type KRAS treated with cetuximab. BRAF V600E, KRAS, NRAS gene mutations, and MSI status were identified using PCR techniques in a population of pre-treated patients who were refractory to fluoropyrimidines, oxaliplatin, and irinotecan. In addition, we evaluated the mutation frequency of the BRAF and NRAS genes and the MSI status of this population. Uni- and multivariate analyses were performed for independent prognostic factors of OS. RESULTS: The median OS was 10.4 months, 6.6 months for patients with right and 11.5 months for left colon cancers (p = 0.02). The frequencies of mutations were BRAF at 3.9% (median OS of 4.9 months), NRAS at 3.38% (median OS of 6.9 months), and MSI-High status at 3.3% (median OS of 4.6 months). The OS, NRAS, and MSI frequencies were similar to those found in other studies that evaluated cetuximab in poly-treated patients and were associated with lower survival rates in univariate analyses. The frequency of BRAF mutations was lower than that found in previous studies. The only variable that remained significant for OS in the multivariate model was tumour laterality, with patients with right colon cancer presenting a worse prognosis (HR = 2.81). CONCLUSION: Although BRAF, NRAS mutations, and MSI-High status were associated with shorter OS in univariate analyses, only tumour laterality remained an independent prognostic factor in the multivariate analysis.

5.
GED gastroenterol. endosc. dig ; GED gastroenterol. endosc. dig;28(4): 142-144, jul.-set. 2009. ilus
Artículo en Inglés | LILACS | ID: lil-776763

RESUMEN

A úlcera solitária benigna do ceco (USBC) é uma doença rara que normalmente se apresenta como uma massa abdominal ou por sangramento digestivo baixo. O diagnóstico definitivo se dá pelo exame anatomopatológico da peça cirúrgica. Os autores reportam caso de paciente jovem que procurou a Unidade de Pronto-Socorro do Hospital Unimar - Marília com quadro clínico, exame físico e testes laboratoriais compatíveis com o diagnóstico de apendicite aguda. Foi indicada laparotomia com abordagem abdominal pela incisão de McBurney. Durante inventário da cavidade peritoneal, foi constatada massa palpável em região cecal e apêndice normal. Uma vez que não se conseguiu afastar uma neoplasia maligna do ceco, optou-se pela hemicolectomia direita seguindo preceitos oncologicos os, O diagnóstico de USBC se deu pelo exame histológico do espécime cirúrgico. Assim como descrito neste caso clínico, usualmente o diagnóstico de USBC se dá pelo exame histológico. Além disso, cerca de 60% a 80% dos pacientes se apresentam inicialmente com quadro clínico de apendicite aguda. O diagnóstico clínico da USBC por meio de uma colonoscopia é muito raro. Devido a isso, o tratamento, na grande maioria das vezes, é a hemicolectomia direita,uma vez que durante o intraoperatório não é possível afastar um câncer do ceco.


Asunto(s)
Humanos , Femenino , Adulto , Ciego/cirugía , Laparotomía , Apendicitis , Enfermedades del Ciego , Colitis Ulcerosa , Diagnóstico Diferencial
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