Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 65
Filtrar
Más filtros

Tipo del documento
Intervalo de año de publicación
1.
Ann Hum Genet ; 88(2): 113-125, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-37807935

RESUMEN

INTRODUCTION: Next generation sequencing technology has greatly reduced the cost and time required for sequencing a genome. An approach that is rapidly being adopted as an alternative method for CNV analysis is the low-pass whole genome sequencing (LP-WGS). Here, we evaluated the performance of LP-WGS to detect copy number variants (CNVs) in clinical cytogenetics. MATERIALS AND METHODS: DNA samples with known CNVs detected by chromosomal microarray analyses (CMA) were selected for comparison and used as positive controls; our panel included 44 DNA samples (12 prenatal and 32 postnatal), comprising a total of 55 chromosome imbalances. The selected cases were chosen to provide a wide range of clinically relevant CNVs, the vast majority being associated with intellectual disability or recognizable syndromes. The chromosome imbalances ranged in size from 75 kb to 90.3 Mb, including aneuploidies and two cases of mosaicism. RESULTS: All CNVs were successfully detected by LP-WGS, showing a high level of consistency and robust performance of the sequencing method. Notably, the size of chromosome imbalances detected by CMA and LP-WGS were compatible between the two different platforms, which indicates that the resolution and sensitivity of the LP-WGS approach are at least similar to those provided by CMA. DISCUSSION: Our data show the potential use of LP-WGS to detect CNVs in clinical diagnosis and confirm the method as an alternative for chromosome imbalances detection. The diagnostic effectiveness and feasibility of LP-WGS, in this technical validation study, were evidenced by a clinically representative dataset of CNVs that allowed a systematic assessment of the detection power and the accuracy of the sequencing approach. Further, since the software used in this study is commercially available, the method can easily be tested and implemented in a routine diagnostic setting.


Asunto(s)
Aneuploidia , Variaciones en el Número de Copia de ADN , Embarazo , Femenino , Humanos , Análisis Costo-Beneficio , Secuenciación Completa del Genoma/métodos , ADN
2.
Am J Med Genet A ; 194(6): e63544, 2024 06.
Artículo en Inglés | MEDLINE | ID: mdl-38258498

RESUMEN

In this pilot study, we aimed to evaluate the feasibility of whole genome sequencing (WGS) as a first-tier diagnostic test for infants hospitalized in neonatal intensive care units in the Brazilian healthcare system. The cohort presented here results from a joint collaboration between private and public hospitals in Brazil considering the initiative of a clinical laboratory to provide timely diagnosis for critically ill infants. We performed trio (proband and parents) WGS in 21 infants suspected of a genetic disease with an urgent need for diagnosis to guide medical care. Overall, the primary indication for genetic testing was dysmorphic syndromes (n = 14, 67%) followed by inborn errors of metabolism (n = 6, 29%) and skeletal dysplasias (n = 1, 5%). The diagnostic yield in our cohort was 57% (12/21) based on cases that received a definitive or likely definitive diagnostic result from WGS analysis. A total of 16 pathogenic/likely pathogenic variants and 10 variants of unknown significance were detected, and in most cases inherited from an unaffected parent. In addition, the reported variants were of different types, but mainly missense (58%) and associated with autosomal diseases (19/26); only three were associated with X-linked diseases, detected in hemizygosity in the proband an inherited from an unaffected mother. Notably, we identified 10 novel variants, absent from public genomic databases, in our cohort. Considering the entire diagnostic process, the average turnaround time from enrollment to medical report in our study was 53 days. Our findings demonstrate the remarkable utility of WGS as a diagnostic tool, elevating the potential of transformative impact since it outperforms conventional genetic tests. Here, we address the main challenges associated with implementing WGS in the medical care system in Brazil, as well as discuss the potential benefits and limitations of WGS as a diagnostic tool in the neonatal care setting.


Asunto(s)
Pruebas Genéticas , Unidades de Cuidado Intensivo Neonatal , Secuenciación Completa del Genoma , Humanos , Brasil/epidemiología , Recién Nacido , Masculino , Femenino , Pruebas Genéticas/métodos , Proyectos Piloto , Lactante , Enfermedades Genéticas Congénitas/diagnóstico , Enfermedades Genéticas Congénitas/genética
3.
Am J Med Genet A ; : e63802, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38924610

RESUMEN

Low-pass whole genome sequencing (LP-WGS) has been applied as alternative method to detect copy number variants (CNVs) in the clinical setting. Compared with chromosomal microarray analysis (CMA), the sequencing-based approach provides a similar resolution of CNV detection at a lower cost. In this study, we assessed the efficiency and reliability of LP-WGS as a more affordable alternative to CMA. A total of 1363 patients with unexplained neurodevelopmental delay/intellectual disability, autism spectrum disorders, and/or multiple congenital anomalies were enrolled. Those patients were referred from 15 nonprofit organizations and university centers located in different states in Brazil. The analysis of LP-WGS at 1x coverage (>50kb) revealed a positive testing result in 22% of the cases (304/1363), in which 219 and 85 correspond to pathogenic/likely pathogenic (P/LP) CNVs and variants of uncertain significance (VUS), respectively. The 16% (219/1363) diagnostic yield observed in our cohort is comparable to the 15%-20% reported for CMA in the literature. The use of commercial software, as demonstrated in this study, simplifies the implementation of the test in clinical settings. Particularly for countries like Brazil, where the cost of CMA presents a substantial barrier to most of the population, LP-WGS emerges as a cost-effective alternative for investigating copy number changes in cytogenetics.

4.
Breast Cancer Res Treat ; 199(1): 127-136, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36881271

RESUMEN

We determined the frequency and mutational spectrum of BRCA1 and BRCA2 in a series of patients at high risk for developing breast cancer from Brazil. A total of 1267 patients were referred for BRCA genetic testing, and no obligation of fulfilling criteria of mutation probability methods for molecular screening was applied. Germline deleterious mutations in BRCA1/2 (i.e., pathogenic/likely pathogenic variants) were identified in 156 out of 1267 patients (12%). We confirm recurrent mutations in BRCA1/2, but we also report three novel mutations in BRCA2, not previously reported in any public databases or other studies. Variants of unknown significance (VUS) represent only 2% in this dataset and most of them were detected in BRCA2. The overall mutation prevalence in BRCA1/2 was higher in patients diagnosed with cancer at age > 35 years old, and with family history of cancer. The present data expand our knowledge of BRCA1/2 germline mutational spectrum, and it is a valuable clinical resource for genetic counseling and cancer management programs in the country.


Asunto(s)
Proteína BRCA1 , Proteína BRCA2 , Neoplasias de la Mama , Adulto , Femenino , Humanos , Brasil/epidemiología , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Predisposición Genética a la Enfermedad , Mutación de Línea Germinal , Mutación , Neoplasias Ováricas/genética
5.
J Aging Phys Act ; 27(2): 242-251, 2019 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-30117347

RESUMEN

This study compared functional demand (FD) between older and younger women walking at habitual and fast speed and determined strength thresholds necessary to maintain FD below 80%. FD was calculated by expressing walking flexion and extension joint torques of the ankle, knee, and hip as a percentage of maximal strength. Young women had an average FD of 65% across joint actions and speeds, whereas older women had FD of 90%. In older women, the greatest FD occurred in the hip musculature. The hip, knee, and ankle extensor strengths required to maintain FD below 80% were 1.66, 1.86, and 0.57 Nm/kg, and flexor strengths were 1.24, 0.49, and 0.69 Nm/kg, respectively. Older women have limited functional reserve to increase gait speed and rely heavily on available hip strength during walking. This study identifies strength targets for the hip, knee, and ankle that will assist in maintaining FD of older women at a sustainable level.


Asunto(s)
Articulación del Tobillo/fisiología , Articulación de la Cadera/fisiología , Articulación de la Rodilla/fisiología , Fuerza Muscular , Caminata/fisiología , Adolescente , Adulto , Factores de Edad , Anciano , Femenino , Humanos , Persona de Mediana Edad , Rango del Movimiento Articular , Torque , Velocidad al Caminar , Adulto Joven
6.
J Pathol ; 233(2): 124-37, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24615332

RESUMEN

The heterogeneous nature of mammary tumours may arise from different initiating genetic lesions occurring in distinct cells of origin. Here, we generated mice in which Brca2, Pten and p53 were depleted in either basal mammary epithelial cells or luminal oestrogen receptor (ER)-negative cells. Basal cell-origin tumours displayed similar histological phenotypes, regardless of the depleted gene. In contrast, luminal ER-negative cells gave rise to diverse phenotypes, depending on the initiating lesions, including both ER-negative and, strikingly, ER-positive invasive ductal carcinomas. Molecular profiling demonstrated that luminal ER-negative cell-origin tumours resembled a range of the molecular subtypes of human breast cancer, including basal-like, luminal B and 'normal-like'. Furthermore, a subset of these tumours resembled the 'claudin-low' tumour subtype. These findings demonstrate that not only do mammary tumour phenotypes depend on the interactions between cell of origin and driver genetic aberrations, but also multiple mammary tumour subtypes, including both ER-positive and -negative disease, can originate from a single epithelial cell type. This is a fundamental advance in our understanding of tumour aetiology.


Asunto(s)
Proteína BRCA2/genética , Neoplasias de la Mama/genética , Carcinoma Ductal de Mama/genética , Células Epiteliales/metabolismo , Regulación Neoplásica de la Expresión Génica , Glándulas Mamarias Animales/metabolismo , Fosfohidrolasa PTEN/genética , Proteína p53 Supresora de Tumor/genética , Animales , Proteína BRCA2/deficiencia , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/metabolismo , Carcinoma Ductal de Mama/patología , Proliferación Celular , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/metabolismo , Transformación Celular Neoplásica/patología , Claudinas/metabolismo , Modelos Animales de Enfermedad , Células Epiteliales/patología , Femenino , Predisposición Genética a la Enfermedad , Humanos , Glándulas Mamarias Animales/patología , Ratones , Ratones Noqueados , Fosfohidrolasa PTEN/deficiencia , Fenotipo , Receptores de Estrógenos/metabolismo , Factores de Tiempo , Proteína p53 Supresora de Tumor/deficiencia
7.
Nat Cell Biol ; 9(8): 961-9, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17643115

RESUMEN

Cell migration driven by the epidermal growth factor receptor (EGFR) propels morphogenesis and involves reorganization of the actin cytoskeleton. Although de novo transcription precedes migration, transcript identity remains largely unknown. Through their actin-binding domains, tensins link the cytoskeleton to integrin-based adhesion sites. Here we report that EGF downregulates tensin-3 expression, and concomitantly upregulates cten, a tensin family member that lacks the actin-binding domain. Knockdown of cten or tensin-3, respectively, impairs or enhances mammary cell migration. Furthermore, cten displaces tensin-3 from the cytoplasmic tail of integrin beta1, thereby instigating actin fibre disassembly. In invasive breast cancer, cten expression correlates not only with high EGFR and HER2, but also with metastasis to lymph nodes. Moreover, treatment of inflammatory breast cancer patients with an EGFR/HER2 dual-specificity kinase inhibitor significantly downregulated cten expression. In conclusion, a transcriptional tensin-3-cten switch may contribute to the metastasis of mammary cancer.


Asunto(s)
Neoplasias de la Mama/metabolismo , Movimiento Celular/fisiología , Factor de Crecimiento Epidérmico/metabolismo , Proteínas de Microfilamentos/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Inhibidores Enzimáticos/metabolismo , Receptores ErbB , Femenino , Humanos , Proteínas de Microfilamentos/genética , Análisis de Secuencia por Matrices de Oligonucleótidos , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Tensinas
8.
J Pathol ; 226(1): 84-96, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22015727

RESUMEN

Adenoid cystic carcinoma (AdCC) is a rare form of triple-negative and basal-like breast cancer that has an indolent clinical behaviour. Four breast AdCCs were recently shown to harbour the recurrent chromosomal translocation t(6;9)(q22-23;p23-24), which leads to the formation of the MYB-NFIB fusion gene. Our aims were (i) to determine the prevalence of the MYB-NFIB fusion gene in AdCCs of the breast; (ii) to characterize the gene copy number aberrations found in AdCCs; and (iii) to determine whether AdCCs are genomically distinct from histological grade-matched or triple-negative and basal-like invasive ductal carcinomas of no special type (IDC-NSTs). The presence of the MYB-NFIB fusion gene was investigated in 13 AdCCs of the breast by fluorescence in situ hybridization (FISH) and reverse transcriptase-PCR (RT-PCR), and MYB and BRCA1 RNA expression was determined by quantitative RT-PCR. Fourteen AdCCs, 14 histological grade-matched IDC-NSTs, and 14 IDC-NSTs of triple-negative and basal-like phenotype were microdissected and subjected to high-resolution microarray-based comparative genomic hybridization (aCGH). The MYB-NFIB fusion gene was detected in all but one AdCC. aCGH analysis demonstrated a relatively low number of copy number aberrations and a lack of recurrent amplifications in breast AdCCs. Contrary to grade-matched IDC-NSTs, AdCCs lacked 1q gains and 16q losses, and in contrast with basal-like IDC-NSTs, AdCCs displayed fewer gene copy number aberrations and expressed MYB and BRCA1 at significantly higher levels. Breast AdCCs constitute an entity distinct from grade-matched and triple-negative and basal-like IDC-NSTs, emphasizing the importance of histological subtyping of triple-negative and basal-like breast carcinomas.


Asunto(s)
Neoplasias de la Mama/genética , Carcinoma Adenoide Quístico/genética , Proteínas de Fusión Oncogénica/genética , Neoplasias de la Mama/patología , Carcinoma Adenoide Quístico/patología , Carcinoma Ductal de Mama/genética , Carcinoma Ductal de Mama/patología , Femenino , Dosificación de Gen , Perfilación de la Expresión Génica , Humanos , Inmunohistoquímica , Hibridación Fluorescente in Situ , Microdisección , Receptor ErbB-3/biosíntesis , Receptor ErbB-3/genética , Receptores de Estrógenos/biosíntesis , Receptores de Estrógenos/genética , Receptores de Progesterona/biosíntesis , Receptores de Progesterona/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Matrices Tisulares
9.
Diagnostics (Basel) ; 13(21)2023 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-37958189

RESUMEN

Homologous recombination deficiency (HRD) has become an important prognostic and predictive biomarker for patients with high-grade serous ovarian cancer who may benefit from poly-ADP ribose polymerase inhibitors (PARPi) and platinum-based therapies. HRD testing provides relevant information to personalize patients' treatment options and has been progressively incorporated into diagnostic laboratories. Here, we assessed the performance of an in-house HRD testing system deployable in a diagnostic clinical setting, comparing results from two commercially available next-generation sequencing (NGS)-based tumor tests (SOPHiA DDMTM HRD Solution and AmoyDx® (HRD Focus Panel)) with the reference assay from Myriad MyChoice® (CDx). A total of 85 ovarian cancer samples were subject to HRD testing. An overall strong correlation was observed across the three assays evaluated, regardless of the different underlying methods employed to assess genomic instability, with the highest pairwise correlation between Myriad and SOPHiA (R = 0.87, p-value = 3.39 × 10-19). The comparison of the assigned HRD status to the reference Myriad's test revealed a positive predictive value (PPV) and negative predictive value (NPV) of 90.9% and 96.3% for SOPHiA's test, while AmoyDx's test achieved 75% PPV and 100% NPV. This is the largest HRD testing evaluation using different methodologies and provides a clear picture of the robustness of NGS-based tests currently offered in the market. Our data shows that the implementation of in-house HRD testing in diagnostic laboratories is technically feasible and can be reliably performed with commercial assays. Also, the turnaround time is compatible with clinical needs, making it an ideal alternative to offer to a broader number of patients while maintaining high-quality standards at more accessible price tiers.

10.
Hum Mol Genet ; 19(13): 2554-66, 2010 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-20385540

RESUMEN

CDH3/P-cadherin is a classical cadherin. Overexpression of which has been associated with proliferative lesions of high histological grade, decreased cell polarity and poor survival of patients with breast cancer. In vitro studies showed that it can be up-regulated by ICI 182,780, suggesting that the lack of ERalpha signalling is responsible for the aberrant P-cadherin overexpression and for its role in inducing breast cancer cell invasion and migration. However, the mechanism by which ER-signalling inhibition leads to P-cadherin expression is still unknown. The aim of this study was to explore the molecular mechanism linking the ERalpha-signalling and P-cadherin-regulated expression in breast cancer cell lines. This study showed that ICI 182,780 is able to increase CDH3 promoter activity, inducing high levels of the active chromatin mark H3 lysine 4 dimethylation. We also observed, for the first time, that the transcription factor C/EBPbeta is able to up-regulate CDH3 promoter activity in breast cancer cells. Moreover, we showed that the expression of P-cadherin and C/EBPbeta are highly associated in human breast carcinomas and linked with a worse prognosis of breast cancer patients. This study demonstrates the existence of an epigenetic regulation by which ICI 182,780 up-regulates P-cadherin expression in MCF-7/AZ breast cancer cells through chromatin remodelling at CDH3 promoter, bringing forward the growing evidence that ERalpha signalling-abrogation by anti-oestrogens is able to induce the expression of ERalpha-repressed genes which, in the appropriate cell biology context, may contribute to a breast cancer cell invasion phenotype.CDH3 GenBank accession no. NT_010498.


Asunto(s)
Cadherinas/genética , Ensamble y Desensamble de Cromatina , Estradiol/análogos & derivados , Regiones Promotoras Genéticas , Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Proteína beta Potenciadora de Unión a CCAAT/metabolismo , Cadherinas/metabolismo , Línea Celular Tumoral , Estradiol/farmacología , Receptor alfa de Estrógeno/metabolismo , Femenino , Fulvestrant , Humanos , Transducción de Señal , Factores de Transcripción/metabolismo , Regulación hacia Arriba
11.
Hum Mol Genet ; 19(4): 697-706, 2010 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-19955118

RESUMEN

Mixed lineage kinase 3 (MLK3) is a serine/threonine kinase, regulating MAPkinase signalling, in which cancer-associated mutations have never been reported. In this study, 174 primary gastrointestinal cancers (48 hereditary and 126 sporadic forms) and 7 colorectal cancer cell lines were screened for MLK3 mutations. MLK3 mutations were significantly associated with MSI phenotype in primary tumours (P = 0.0005), occurring in 21% of the MSI carcinomas. Most MLK3 somatic mutations identified were of the missense type (62.5%) and more than 80% of them affected evolutionarily conserved residues. A predictive 3D model points to the functional relevance of MLK3 missense mutations, which cluster in the kinase domain. Further, the model shows that most of the altered residues in the kinase domain probably affect MLK3 scaffold properties, instead of its kinase activity. MLK3 missense mutations showed transforming capacity in vitro and cells expressing the mutant gene were able to develop locally invasive tumours, when subcutaneously injected in nude mice. Interestingly, in primary tumours, MLK3 mutations occurred in KRAS and/or BRAF wild-type carcinomas, although not being mutually exclusive genetic events. In conclusion, we have demonstrated for the first time the presence of MLK3 mutations in cancer and its association to mismatch repair deficiency. Further, we demonstrated that MLK3 missense mutations found in MSI gastrointestinal carcinomas are functionally relevant.


Asunto(s)
Reparación de la Incompatibilidad de ADN , Neoplasias Gastrointestinales/genética , Quinasas Quinasa Quinasa PAM/genética , Mutación Missense , Secuencia de Aminoácidos , Animales , Línea Celular Tumoral , Neoplasias Gastrointestinales/enzimología , Humanos , Quinasas Quinasa Quinasa PAM/química , Quinasas Quinasa Quinasa PAM/metabolismo , Ratones , Ratones Desnudos , Datos de Secuencia Molecular , Proteina Quinasa Quinasa Quinasa 11 Activada por Mitógeno
12.
Sci Rep ; 12(1): 15184, 2022 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-36071085

RESUMEN

Chromosomal microarray analysis (CMA) has been recommended and practiced routinely since 2010 both in the USA and Europe as the first-tier cytogenetic test for patients with unexplained neurodevelopmental delay/intellectual disability, autism spectrum disorders, and/or multiple congenital anomalies. However, in Brazil, the use of CMA is still limited, due to its high cost and complexity in integrating the results from both the private and public health systems. Although Brazil has one of the world's largest single-payer public healthcare systems, nearly all patients referred for CMA come from the private sector, resulting in only a small number of CMA studies in Brazilian cohorts. To date, this study is by far the largest Brazilian cohort (n = 5788) studied by CMA and is derived from a joint collaboration formed by the University of São Paulo and three private genetic diagnostic centers to investigate the genetic bases of neurodevelopmental disorders and congenital abnormalities. We identified 2,279 clinically relevant CNVs in 1886 patients, not including the 26 cases of UPD found. Among detected CNVs, the corresponding frequency of each category was 55.6% Pathogenic, 4.4% Likely Pathogenic and 40% VUS. The diagnostic yield, by taking into account Pathogenic, Likely Pathogenic and UPDs, was 19.7%. Since the rational for the classification is mostly based on Mendelian or highly penetrant variants, it was not surprising that a second event was detected in 26% of those cases of predisposition syndromes. Although it is common practice to investigate the inheritance of VUS in most laboratories around the world to determine the inheritance of the variant, our results indicate an extremely low cost-benefit of this approach, and strongly suggest that in cases of a limited budget, investigation of the parents of VUS carriers using CMA should not be prioritized.


Asunto(s)
Discapacidad Intelectual , Trastornos del Neurodesarrollo , Brasil/epidemiología , Niño , Discapacidades del Desarrollo/diagnóstico , Discapacidades del Desarrollo/epidemiología , Discapacidades del Desarrollo/genética , Humanos , Discapacidad Intelectual/diagnóstico , Discapacidad Intelectual/genética , Análisis por Micromatrices , Trastornos del Neurodesarrollo/epidemiología , Trastornos del Neurodesarrollo/genética
13.
Breast Cancer Res ; 13(3): 212, 2011 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-21787441

RESUMEN

Breast cancer comprises a collection of diseases with distinctive clinical, histopathological, and molecular features. Importantly, tumors with similar histological features may display disparate clinical behaviors. Gene expression profiling using microarray technologies has improved our understanding of breast cancer biology and has led to the development of a breast cancer molecular taxonomy and of multigene 'signatures' to predict outcome and response to systemic therapies. The use of these prognostic and predictive signatures in routine clinical decision-making remains controversial. Here, we review the clinical relevance of microarray-based profiling of breast cancer and discuss its impact on patient management.


Asunto(s)
Neoplasias de la Mama/clasificación , Neoplasias de la Mama/genética , Perfilación de la Expresión Génica , Neoplasias de la Mama/patología , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Resultado del Tratamiento
14.
Int J Cancer ; 128(7): 1606-13, 2011 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-20533283

RESUMEN

Microsatellite instability (MSI) is a major pathway involved in gastric carcinogenesis occurring in 20% of gastric cancer (GC). However, it is not clear whether MSI phenotype preferentially occurs in the sporadic or familial GC, when stringent inclusion criteria are used. The aim of this study was to compare the frequency of MSI and hypermethylation of MLH1 promoter in a large series of familial GC patients (non-HNPCC and non-CDH1-related) and sporadic cases. Additionally, we analysed the immunoexpression of MMR proteins in a fraction of cases. Overall, the frequency of familial GC was 7.1%, and the frequency of hereditary tumours was 4.6%. MSI phenotype and MLH1 hypermethylation frequencies were not statistical different between familial and sporadic GC settings. Further, the MSI phenotype was not associated with any clinico-pathological features studied in the familial GC setting, whereas in the sporadic setting, it was associated with older age, female gender and intestinal histotype. Using our stringent Amsterdam-based clinical criteria to select familial GC (number of cases, age of onset), we verified that sporadic and familial cases differed in gender but shared histopathological features. We verified that the frequency of MSI was similar in familial and sporadic GC settings, demonstrating that this molecular phenotype is not a hallmark of familial GC in contrast to what is verified in HNPCC. Moreover, we observed that the frequency of MLH1 hypermethylation is similar in sporadic and familial cases suggesting that in both settings MSI is not associated to MMR genetic alterations but in contrast to epigenetic deregulation.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Inestabilidad de Microsatélites , Repeticiones de Microsatélite , Regiones Promotoras Genéticas , Neoplasias Gástricas/genética , Proteínas Adaptadoras Transductoras de Señales/genética , Anciano , Proteínas de Unión al ADN/genética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Homólogo 1 de la Proteína MutL , Proteína 2 Homóloga a MutS/genética , Proteínas Nucleares/genética , Fenotipo , Neoplasias Gástricas/metabolismo
15.
BMC Cancer ; 11: 299, 2011 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-21762477

RESUMEN

BACKGROUND: A breast cancer prognostic tool should ideally be applicable to all types of invasive breast lesions. A number of studies have shown histopathological grade to be an independent prognostic factor in breast cancer, adding prognostic power to nodal stage and tumour size. The Nottingham Prognostic Index has been shown to accurately predict patient outcome in stratified groups with a follow-up period of 15 years after primary diagnosis of breast cancer. Clinically, breast tumours that lack the expression of Oestrogen Receptor, Progesterone Receptor and Human Epidermal growth factor Receptor 2 (HER2) are identified as presenting a "triple-negative" phenotype or as triple-negative breast cancers. These poor outcome tumours represent an easily recognisable prognostic group of breast cancer with aggressive behaviour that currently lack the benefit of available systemic therapy. There are conflicting results on the prevalence of lymph node metastasis at the time of diagnosis in triple-negative breast cancer patients but it is currently accepted that triple-negative breast cancer does not metastasize to axillary nodes and bones as frequently as the non-triple-negative carcinomas, favouring instead, a preferentially haematogenous spread. Hypothetically, this particular tumour dissemination pattern would impair the reliability of using Nottingham Prognostic Index as a tool for triple-negative breast cancer prognostication. METHODS: The present study tested the effectiveness of the Nottingham Prognostic Index in stratifying breast cancer patients of different subtypes with special emphasis in a triple-negative breast cancer patient subset versus non- triple-negative breast cancer. RESULTS: We demonstrated that besides the fact that TNBC disseminate to axillary lymph nodes as frequently as luminal or HER2 tumours, we also showed that TNBC are larger in size compared with other subtypes and almost all grade 3. Additionally, survival curves demonstrated that these prognostic factors are equally important to stratify different survival outcomes in non-TNBC as in TNBC. We also showed that the NPI retains the ability to stratify and predict survival of TNBC patients. CONCLUSION: The importance of this study relies on the need of prognostication improvements on TNBC, showing, at a clinical standpoint, that Nottingham Prognostic Index is as a truthful prognostic tool in TNBC.


Asunto(s)
Neoplasias de la Mama/metabolismo , Receptor ErbB-2/metabolismo , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Mama/metabolismo , Mama/patología , Neoplasias de la Mama/diagnóstico , Femenino , Humanos , Inmunohistoquímica/estadística & datos numéricos , Estimación de Kaplan-Meier , Metástasis Linfática , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Modelos de Riesgos Proporcionales , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Análisis de Matrices Tisulares , Carga Tumoral
16.
Mol Syndromol ; 12(5): 312-320, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34602959

RESUMEN

Duplication of the distal 1q and 4p segments are both characterized by the presence of intellectual disability/neurodevelopmental delay and dysmorphisms. Here, we describe a male with a complex chromosome rearrangement (CCR) presenting with overlapping clinical findings between these 2 syndromes. In order to better characterize this CCR, classical karyotyping, FISH, and chromosomal microarray analysis were performed on material from the patient and his parents, which revealed an unbalanced karyotype with duplications at 1q41q43 and 4p15.2p14 in the proband. The rearrangements, which were derived from a maternal balanced karyotype, included an insertion of a segment from the long to the short arm of chromosome 1, a balanced translocation involving chromosomes 14 and 18, and an insertion of a segment from the short arm of chromosome 4 into the derived chromosome 14. This study aimed to better define the clinical history and prognosis of a patient with this rare category of chromosomal aberration. Our results suggest that the frequency of CCR in the general population may be underestimated; when balanced, they may not have a phenotypic effect. Moreover, they emphasize the need for cytogenetic techniques complementary to chromosomal microarray for proper genetic counseling.

17.
Eur J Med Genet ; 64(5): 104195, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33746038

RESUMEN

The cytochrome c-oxidase (COX) enzyme, also known as mitochondrial complex IV (MT-C4D), is a transmembrane protein complex found in mitochondria. COX deficiency is one of the most frequent causes of electron transport chain defects in humans. Therefore, high energy demand organs and tissues are affected in patients with mutations in the COX15 gene, with variable phenotypic expressiveness. We describe the case of a male newborn with hypertrophic cardiomyopathy and serum and cerebrospinal fluid hyperlacticaemia, whose exome sequencing revealed two variants in a compound heterozygous state: c.232G > A; p.(Gly78Arg), classified as likely pathogenic, and c.452C > G; p.(Ser151Ter), as pathogenic; the former never previously described in the literature.


Asunto(s)
Cardiomiopatía Hipertrófica/genética , Deficiencia de Citocromo-c Oxidasa/genética , Complejo IV de Transporte de Electrones/genética , Encefalomiopatías Mitocondriales/genética , Cardiomiopatía Hipertrófica/patología , Deficiencia de Citocromo-c Oxidasa/patología , Heterocigoto , Humanos , Recién Nacido , Masculino , Encefalomiopatías Mitocondriales/patología , Mutación , Fenotipo
18.
BMC Cancer ; 10: 483, 2010 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-20831823

RESUMEN

BACKGROUND: Breast cancer is a heterogeneous disease associated with different patient prognosis and responses to therapy. Vitamin D has been emerging as a potential treatment for cancer, as it has been demonstrated that it modulates proliferation, apoptosis, invasion and metastasis, among others. It acts mostly through the Vitamin D receptor (VDR) and the synthesis and degradation of this hormone are regulated by the enzymes CYP27B1 and CYP24A1, respectively. We aimed to study the expression of these three proteins by immunohistochemistry in a series of breast lesions. METHODS: We have used a cohort comprising normal breast, benign mammary lesions, carcinomas in situ and invasive carcinomas and assessed the expression of the VDR, CYP27B1 and CYP24A1 by immunohistochemistry. RESULTS: The results that we have obtained show that all proteins are expressed in the various breast tissues, although at different amounts. The VDR was frequently expressed in benign lesions (93.5%) and its levels of expression were diminished in invasive tumours (56.2%). Additionally, the VDR was strongly associated with the oestrogen receptor positivity in breast carcinomas. CYP27B1 expression is slightly lower in invasive carcinomas (44.6%) than in benign lesions (55.8%). In contrast, CYP24A1 expression was augmented in carcinomas (56.0% in in situ and 53.7% in invasive carcinomas) when compared with that in benign lesions (19.0%). CONCLUSIONS: From this study, we conclude that there is a deregulation of the Vitamin D signalling and metabolic pathways in breast cancer, favouring tumour progression. Thus, during mammary malignant transformation, tumour cells lose their ability to synthesize the active form of Vitamin D and respond to VDR-mediated Vitamin D effects, while increasing their ability to degrade this hormone.


Asunto(s)
25-Hidroxivitamina D3 1-alfa-Hidroxilasa/metabolismo , Neoplasias de la Mama/metabolismo , Mama/metabolismo , Receptores de Calcitriol/metabolismo , Esteroide Hidroxilasas/metabolismo , Vitamina D/metabolismo , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Western Blotting , Mama/patología , Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/metabolismo , Carcinoma Ductal de Mama/patología , Carcinoma Intraductal no Infiltrante/metabolismo , Carcinoma Intraductal no Infiltrante/patología , Estudios de Cohortes , Progresión de la Enfermedad , Femenino , Perfilación de la Expresión Génica , Humanos , Técnicas para Inmunoenzimas , Redes y Vías Metabólicas , Estadificación de Neoplasias , Análisis de Secuencia por Matrices de Oligonucleótidos , Pronóstico , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal , Vitamina D3 24-Hidroxilasa
19.
Blood Coagul Fibrinolysis ; 31(1): 65-70, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31687989

RESUMEN

: The objective is to report a patient with congenital afibrinogenemia and vascular abnormalities and also review the clinical and molecular issues. The female proband, diagnosed with congenital afibrinogenemia, was admitted at a hospital due to a hemorrhagic shock. Angiotomography revealed ectasias from ascending branch to the abdominal aorta, with multiple calcifications and atheroma. Clinical exome identified a homozygous novel pathogenic variant in FGG gene. In our review the main symptom, at diagnosis, was umbilical cord bleeding and the degree of clinical involvement varied from asymptomatic to severe. The FGA gene was the most affected and possible hot spots were observed. Variants considered as loss of function were the most frequent. The association of vascular abnormalities in a patient with congenital afibrinogenemia alerts for a closer follow-up of vascular issues in these patients.


Asunto(s)
Afibrinogenemia/genética , Fibrinógeno/genética , Afibrinogenemia/sangre , Niño , Femenino , Humanos
20.
Breast Cancer Res ; 11(3): R40, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19549328

RESUMEN

INTRODUCTION: The expression of additional genes, other than oestrogen receptor (ER), may be important to the hormone-responsive phenotype of breast cancer. Microarray analyses have revealed that forkhead box A1 (FOXA1) and GATA binding protein 3 (GATA-3) are expressed in close association with ERalpha, both encoding for transcription factors with a potential involvement in the ERalpha-mediated action in breast cancer. The purpose of this study was to explore if the expression of FOXA1 and GATA-3 may provide an opportunity to stratify subsets of patients that could have better outcome, among the ERalpha-negative/poor prognosis breast cancer group. METHODS: We evaluate FOXA1 and GATA-3 expression in 249 breast carcinomas by immunohistochemistry, associating it with breast cancer molecular markers, clinicopathological features and patient's survival. The clinicopathological features and immunohistochemical markers of the tumours were compared using the chi-square test and ANOVA. Disease-free survival was analysed through Kaplan-Meier survival curves and Cox regression. RESULTS: FOXA1 expression was demonstrated in 42% of invasive carcinomas, while GATA-3 was detected in 48% of the cases. FOXA1 expression was inversely associated with tumour size, Nottingham Prognostic Index, histological grade, lymph vascular invasion, lymph node stage and human epidermal growth factor receptor-2 (HER-2) overexpression, while GATA-3 expression showed inverse association with histological grade and HER-2. Both FOXA1 and GATA-3 were directly associated with ERalpha and progesterone receptor. Among FOXA1-positive tumours, 83.1% are comprised in the luminal A subtype, similar to GATA-3 where 87.7% of positive tumours were classified within this molecular subtype. In the subset of ERalpha-negative patients, those who were FOXA1-negative had a 3.61-fold increased risk of breast cancer recurrence when compared with the FOXA1-positive. CONCLUSIONS: FOXA1 was a significant predictor of good outcome in breast cancer, whereas GATA-3 was an important luminal marker. The expression of FOXA1 may be used for risk stratification among ERalpha-negative patients.


Asunto(s)
Factor de Transcripción GATA3/biosíntesis , Regulación Neoplásica de la Expresión Génica , Factor Nuclear 3-alfa del Hepatocito/biosíntesis , Receptores de Estrógenos/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Supervivencia sin Enfermedad , Femenino , Humanos , Inmunohistoquímica/métodos , Persona de Mediana Edad , Pronóstico , Modelos de Riesgos Proporcionales , Resultado del Tratamiento
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA