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1.
Transl Vis Sci Technol ; 12(12): 8, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-38060234

RESUMO

Purpose: Latinx populations have the highest rates of visual impairment and blindness of any ethnic group in the United States, with most cases of diabetic retinopathy remaining undiagnosed. We aimed to identify factors influencing adherence with diabetic eye screening in Latinx communities. Methods: We conducted semistructured individual interviews with adult Latinx patients in Dane County, WI. Interviews were transcribed verbatim, translated from Spanish to English, and analyzed using QSR NVivo software. We performed both inductive open coding and deductive coding using the National Institute on Minority Health and Health Disparities Research Framework, as well as the Campbell and Egede Model. Results: All participants (n = 20) self-identified as Latinx and were diagnosed with type 2 diabetes. The mean age was 61.5 years (range 33-79 years). Most participants were uninsured (60%), self-reported low or moderate health literacy (60%), and preferred to speak Spanish during their clinic appointments (75%). Individual-level barriers to diabetic eye screening included limited eye health literacy, lack of insurance coverage, and low self-efficacy with diabetes management. Health system-level facilitators included a recommendation to obtain eye screening from a primary care provider and the use of nonwritten forms of patient education. Community-level barriers included social isolation, concerns about inconveniencing others, machismo, and immigration status. Conclusions: We identified several health system- and community-level factors, in addition to individual-level factors, influencing adherence with diabetic eye screening in Latinx communities. Translational Relevance: Strategies addressing these factors may enhance the effectiveness of interventions to prevent blindness from diabetes and contribute to advancing health equity in Latinx communities.


Assuntos
Diabetes Mellitus Tipo 2 , Retinopatia Diabética , Adulto , Humanos , Estados Unidos , Pessoa de Meia-Idade , Idoso , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/epidemiologia , Hispânico ou Latino , Cegueira
2.
J Adv Res ; 50: 145-158, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36323370

RESUMO

INTRODUCTION: Whole-genome sequencing using nanopore technologies can uncover structural variants, which are DNA rearrangements larger than 50 base pairs. Nanopore technologies can also characterize their boundaries with single-base accuracy, owing to the kilobase-long reads that encompass either full variants or their junctions. Other methods, such as next-generation short read sequencing or PCR assays, are limited in their capabilities to detect or characterize structural variants. However, the existing software for nanopore sequencing data analysis still reports incomplete variant sets, which also contain erroneous calls, a considerable obstacle for the molecular diagnosis or accurate genotyping of populations. METHODS: We compared multiple factors affecting variant calling, such as reference genome version, aligner (minimap2, NGMLR, and lra) choice, and variant caller combinations (Sniffles, CuteSV, SVIM, and NanoVar), to find the optimal group of tools for calling large (>50 kb) deletions and duplications, using data from seven patients exhibiting gross gene defects on SERPINC1 and from a reference variant set as the control. The goal was to obtain the most complete, yet reasonably specific group of large variants using a single cell of PromethION sequencing, which yielded lower depth coverage than short-read sequencing. We also used a custom method for the statistical analysis of the coverage value to refine the resulting datasets. RESULTS: We found that for large deletions and duplications (>50 kb), the existing software performed worse than for smaller ones, in terms of both sensitivity and specificity, and newer tools had not improved this. Our novel software, disCoverage, could polish variant callers' results, improving specificity by up to 62% and sensitivity by 15%, the latter requiring other data or samples. CONCLUSION: We analyzed the current situation of >50-kb copy number variants with nanopore sequencing, which could be improved. The methods presented in this work could help to identify the known deletions and duplications in a set of patients, while also helping to filter out erroneous calls for these variants, which might aid the efforts to characterize a not-yet well-known fraction of genetic variability in the human genome.


Assuntos
Sequenciamento por Nanoporos , Nanoporos , Humanos , Análise de Sequência de DNA/métodos , Variações do Número de Cópias de DNA/genética , Genoma Humano
3.
Cancers (Basel) ; 14(16)2022 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-36011023

RESUMO

The incidence of early-onset colorectal cancer (EOCRC; age younger than 50 years) has been progressively increasing over the last decades globally, with causes unexplained. A distinct molecular feature of EOCRC is that compared with cases of late-onset colorectal cancer, in EOCRC cases, there is a higher incidence of Nodal Modulator 1 (NOMO1) somatic deletions. However, the mechanisms of NOMO1 in early-onset colorectal carcinogenesis are currently unknown. In this study, we show that in 30% of EOCRCs with heterozygous deletion of NOMO1, there were pathogenic mutations in this gene, suggesting that NOMO1 can be inactivated by deletion or mutation in EOCRC. To study the role of NOMO1 in EOCRC, CRISPR/cas9 technology was employed to generate NOMO1 knockout HCT-116 (EOCRC) and HS-5 (bone marrow) cell lines. NOMO1 loss in these cell lines did not perturb Nodal pathway signaling nor cell proliferation. Expression microarrays, RNA sequencing, and protein expression analysis by LC-IMS/MS showed that NOMO1 inactivation deregulates other signaling pathways independent of the Nodal pathway, such as epithelial-mesenchymal transition and cell migration. Significantly, NOMO1 loss increased the migration capacity of CRC cells. Additionally, a gut-specific conditional NOMO1 KO mouse model revealed no subsequent tumor development in mice. Overall, these findings suggest that NOMO1 could play a secondary role in early-onset colorectal carcinogenesis because its loss increases the migration capacity of CRC cells. Therefore, further study is warranted to explore other signalling pathways deregulated by NOMO1 loss that may play a significant role in the pathogenesis of the disease.

4.
J Mol Diagn ; 24(5): 462-475, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35218943

RESUMO

Inherited antithrombin deficiency, the most severe form of thrombophilia, is predominantly caused by variants in SERPINC1. Few causal structural variants have been described, usually detected by multiplex ligation-dependent probe amplification or cytogenetic arrays, which only define the gain or loss and the approximate size and location. This study has done a complete dissection of the structural variants affecting SERPINC1 of 39 unrelated patients with antithrombin deficiency using multiplex ligation-dependent probe amplification, comparative genome hybridization array, long-range PCR, and whole genome nanopore sequencing. Structural variants, in all cases only affecting one allele, were deleterious and caused a severe type I deficiency. Most defects were deletions affecting exons of SERPINC1 (82.1%), but the whole cohort was heterogeneous, as tandem duplications, deletion of introns, or retrotransposon insertions were also detected. Their size was also variable, ranging from 193 bp to 8 Mb, and in 54% of the cases involved neighboring genes. All but two structural variants had repetitive elements and/or microhomologies in their breakpoints, suggesting a common mechanism of formation. This study also suggested regions recurrently involved in structural variants causing antithrombin deficiency and found three structural variants with a founder effect: the insertion of a retrotransposon, duplication of exon 6, and a 20-gene deletion. Finally, nanopore sequencing was determined to be the most appropriate method to identify and characterize all structural variants at nucleotide level, independently of their size or type.


Assuntos
Deficiência de Antitrombina III , Retroelementos , Deficiência de Antitrombina III/genética , Antitrombinas , Éxons/genética , Humanos , Íntrons
5.
Sci Rep ; 11(1): 2202, 2021 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-33500439

RESUMO

Rectal cancer (RC) appears to behave differently compared with colon cancer. We aimed to analyze existence of different subtypes of RC depending on distinct features (age of onset and the presence of synchronous primary malignant neoplasms). We compared the clinicopathological, familial and molecular features of three different populations diagnosed with RC (early-onset RC [EORC], late-onset RC, and synchronous RC [SRC]). Eighty-five RCs were identified and were evaluated according to their microsatellite instability, CpG Island Methylator Phenotype (CIMP) and chromosomal instability, as assessed by Next Generation Sequencing and microarray-based comparative genomic hybridization approaches. The results were subjected to cluster analysis. SRCs displayed the most specific characteristics including a trend for the development of multiple malignant neoplasms, a greater proportion of CIMP-High tumors (75%) and more frequent genomic alterations. These findings were confirmed by a clustering analysis that stratified RCs according to their genomic alterations. We also found that EORCs exhibited their own features including an important familial cancer component and a remarkable rate of mutations in TP53 (53%). Together, heterogeneity in RC characteristics by age of disease-onset and SRC warrants further study to optimize tailored prevention, detection and intervention strategies-particularly among young adults.


Assuntos
Neoplasias Primárias Múltiplas/genética , Neoplasias Primárias Múltiplas/patologia , Neoplasias Retais/genética , Neoplasias Retais/patologia , Adulto , Idade de Início , Idoso , Instabilidade Cromossômica/genética , Análise por Conglomerados , Ilhas de CpG/genética , Metilação de DNA/genética , Família , Feminino , Genoma Humano , Humanos , Masculino , Instabilidade de Microssatélites , Pessoa de Meia-Idade , Mutação/genética , Fenótipo
7.
Int J Mol Sci ; 21(12)2020 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-32585800

RESUMO

Complex neurodevelopmental syndromes frequently have an unknown etiology, in which genetic factors play a pathogenic role. This study utilizes whole-exome sequencing (WES) to examine four members of a family with a son presenting, since birth, with epileptic-like crises, combined with cerebral palsy, severe neuromotor and developmental delay, dystonic tetraparexia, axonal motor affectation, and hyper-excitability of unknown origin. The WES study detected within the patient a de novo heterozygous in-frame duplication of thirty-six nucleotides within exon 7 of the human KCNQ2 gene. This insertion duplicates the first twelve amino acids of the calmodulin binding site I. Molecular dynamics simulations of this KCNQ2 peptide duplication, modelled on the 3D structure of the KCNQ2 protein, suggest that the duplication may lead to the dysregulation of calcium inhibition of this protein function.


Assuntos
Deficiências do Desenvolvimento/patologia , Síndromes Epilépticas/patologia , Éxons , Duplicação Gênica , Canal de Potássio KCNQ2/genética , Mutação , Transtornos do Neurodesenvolvimento/patologia , Criança , Deficiências do Desenvolvimento/complicações , Deficiências do Desenvolvimento/genética , Síndromes Epilépticas/complicações , Síndromes Epilépticas/genética , Humanos , Masculino , Transtornos do Neurodesenvolvimento/complicações , Transtornos do Neurodesenvolvimento/genética , Fenótipo , Prognóstico
8.
Sci Rep ; 9(1): 10516, 2019 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-31324877

RESUMO

Colorectal cancer (CRC) with CpG island methylator phenotype (CIMP) is recognized as a subgroup of CRC that shows association with particular genetic defects and patient outcomes. We analyzed CIMP status of 229 individuals with CRC using an eight-marker panel (CACNA1G, CDKN2A, CRABP1, IGF2, MLH1, NEUROG1, RUNX3 and SOCS1); CIMP-(+) tumors were defined as having ≥ 5 methylated markers. Patients were divided into individuals who developed a "unique" CRC, which were subclassified into early-onset CRC (EOCRC) and late-onset CRC (LOCRC), and patients with multiple primary CRCs subclassified into synchronous CRC (SCRC) and metachronous CRC (MCRC). We found 9 (15.2%) CIMP-(+) EOCRC patients related with the proximal colon (p = 0.008), and 19 (26.8%) CIMP-(+) LOCRC patients associated with tumor differentiation (p = 0.045), MSI status (p = 0.021) and BRAF mutation (p = 0.001). Thirty-five (64.8%) SCRC patients had at least one CIMP-(+) tumor and 20 (44.4%) MCRC patients presented their first tumor as CIMP-(+). Thirty-nine (72.2%) SCRC patients showed concordant CIMP status in their simultaneous tumors. The differences in CIMP-(+) frequency between groups may reflect the importance of taking into account several criteria for the development of multiple primary neoplasms. Additionally, the concordance between synchronous tumors suggests CIMP status is generally maintained in SCRC patients.


Assuntos
Adenocarcinoma/genética , Neoplasias Colorretais/genética , Ilhas de CpG , Metilação de DNA , Neoplasias Primárias Múltiplas/genética , Adenoma/genética , Adulto , Idade de Início , Idoso , Diferenciação Celular , Feminino , Genes Neoplásicos , Genes ras , Mutação em Linhagem Germinativa , Humanos , Masculino , Instabilidade de Microssatélites , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética
9.
PLoS One ; 14(5): e0216472, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31095598

RESUMO

Comparative studies of colorectal cancer (CRC) according to the age of onset have found differences between early-onset CRC (EOCRC) and late-onset CRC (LOCRC). Using this as a starting point, we wished to determine whether intermediate-onset CRC (IOCRC) might also be considered as an independent group within CRC. We performed a retrospective comparative study of the clinicopathological and familial features, as well as of the symptoms and their duration, of a total of 272 subjects diagnosed with CRC classified into three groups according to the age-of-onset (98 EOCRC, 83 IOCRC and 91 LOCRC). The results show that from a clinicopathological point of view, IOCRC shared certain features with EOCRC (gender, prognosis), and with LOCRC (multiple primary CRCs), whereas it also had characteristics that were specific for IOCRC (mean number of associated polyps). A gradual progression was observed from EOCRC to LOCRC from a greater family aggregation to sporadic cases, in parallel with a change of Lynch Syndrome cases to the sporadic microsatellite instability pathway, with the IOCRC being a boundary group that is more related to EOCRC. With respect to symptoms, duration and correlation with stages, IOCRC appeared more similar to EOCRC. Clinically, IOCRC behaves as a transitional group between EOCRC and LOCRC, with features in common with both groups, but also with IOCRC-specific features. Excluding cases with familial cancer history, the awareness for EOCRC diagnosis should be extended to IOCRC.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais Hereditárias sem Polipose , Instabilidade de Microssatélites , Adulto , Idade de Início , Idoso , Neoplasias do Colo/genética , Neoplasias do Colo/mortalidade , Neoplasias do Colo/patologia , Neoplasias Colorretais Hereditárias sem Polipose/genética , Neoplasias Colorretais Hereditárias sem Polipose/mortalidade , Neoplasias Colorretais Hereditárias sem Polipose/patologia , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Taxa de Sobrevida
10.
Rev. neurol. (Ed. impr.) ; 68(7): 295-300, 1 abr., 2019. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-183314

RESUMO

Introducción. La amnesia aguda aislada es una forma excepcional de presentación del ictus talámico. Se analizan el perfil clínico, el diagnóstico, el tratamiento y el pronóstico de estos pacientes. Casos clínicos. Revisión retrospectiva de los casos de infarto talámico que se presentaron exclusivamente como amnesia aguda en nuestro hospital terciario universitario (n = 3) y revisión de casos similares en PubMed (n = 20). El 48% presentaba al menos un factor de riesgo de ictus (hipertensión arterial, dislipidemia, diabetes mellitus, fibrilación auricular o ictus previo). La amnesia fue anterógrada en tres casos (13%) y global en los otros 20 (87%). El infarto se detectó en estudio de neuroimagen en las primeras 24 horas en un paciente (4%) y posteriormente en los demás, y la media de días hasta el diagnóstico fue de 11. La tomografía computarizada inicial fue normal en cinco (22%) pacientes. Precisaron estudio por resonancia magnética ocho (35%) casos para detectar el infarto. De éstos, cuatro sujetos se estudiaron directamente con resonancia magnética. La amnesia presentó una mejoría clara en ocho (35%) pacientes, y la recuperación fue completa en tres (13%). Las secuelas mnésicas que interferían la capacidad funcional se presentaron en 15 pacientes (65%). La clínica persistió menos de 24 horas en dos pacientes (9%). Ningún caso recibió tratamiento revascularizador en fase aguda. Conclusión. Los infartos talámicos que comienzan de forma exclusiva con amnesia presentan notables dificultades diagnósticas que repercuten negativamente en su tratamiento en la fase aguda. Estos infartos pueden producir un déficit mnésico funcionalmente discapacitante en un porcentaje elevado de pacientes


Introduction. Isolated acute amnesia is an exceptional presenting symptom of thalamic stroke. This study analyses the clinical profile, the diagnosis, the treatment and the prognosis of these patients. Case reports. We conducted a retrospective review of the cases of thalamic infarct that presented exclusively as acute amnesia in our university tertiary hospital (n = 3) and a review of similar cases in PubMed (n = 20). 48% presented at least one risk factor of stroke (arterial hypertension, dyslipidaemia, diabetes mellitus, atrial fibrillation or a previous stroke). Amnesia was anterograde in three cases (13%) and global in the remaining 20 (87%). The infarct was detected in neuroimaging studies carried out within the first 24 hours in one patient (4%) and later in all the others; the average time until a diagnosis was established was 11 days. The initial CT scan was normal in five patients (22%). Eight cases (35%) required magnetic resonance imaging to detect the infarct. Of these, four subjects were studied directly with MR imaging. Amnesia clearly improved in eight patients (35%), and three of them (13%) made a full recovery. Fifteen patients (65%) presented mnemonic sequelae that interfered with their functional capacity. The clinical picture lasted less than 24 hours in two patients (9%). None of the cases received revasculisation therapy in the acute phase. Conclusion. The diagnosis of thalamic infarcts that begin exclusively with amnesia is very difficult and this has negative repercussions on their treatment in the acute phase. These infarcts can produce a functionally disabling memory deficit in a high percentage of patients


Assuntos
Humanos , Masculino , Idoso , Doenças Talâmicas/complicações , Doenças Talâmicas/diagnóstico , Infarto Cerebral/complicações , Infarto/diagnóstico por imagem , Amnésia/etiologia , Tomografia Computadorizada por Raios X , Imageamento por Ressonância Magnética , Infarto/terapia , Doença Aguda , Prognóstico
11.
Int J Mol Sci ; 20(4)2019 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-30813366

RESUMO

Our aim was to characterize and validate that the location and age of onset of the tumor are both important criteria to classify colorectal cancer (CRC). We analyzed clinical and molecular characteristics of early-onset CRC (EOCRC) and late-onset CRC (LOCRC), and we compared each tumor location between both ages-of-onset. In right-sided colon tumors, early-onset cases showed extensive Lynch syndrome (LS) features, with a relatively low frequency of chromosomal instability (CIN), but a high CpG island methylation phenotype. Nevertheless, late-onset cases showed predominantly sporadic features and microsatellite instability cases due to BRAF mutations. In left colon cancers, the most reliable clinical features were the tendency to develop polyps as well as multiple primary CRC associated with the late-onset subset. Apart from the higher degree of CIN in left-sided early-onset cancers, differential copy number alterations were also observed. Differences among rectal cancers showed that early-onset rectal cancers were diagnosed at later stages, had less association with polyps, and more than half of them were associated with a familial LS component. Stratifying CRC according to both location and age-of-onset criteria is meaningful, not only because it correlates the resulting categories with certain molecular bases, but with the confirmation across larger studies, new therapeutical algorithms could be defined according to this subclassification.


Assuntos
Neoplasias Colorretais/classificação , Neoplasias Colorretais/patologia , Idade de Início , Neoplasias Colorretais/genética , Dosagem de Genes , Humanos
12.
Int J Cancer ; 144(7): 1596-1608, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30151896

RESUMO

To analyze the possible clonal origin of a part of Synchronous colorectal cancer (SCRC), we studied 104 paired-SCRCs from 52 consecutive patients without hereditary forms of CRC. We used a Single-Nucleotide Polymorphism array to characterize the genomic profiles, and subsequently used a statistical application to define them according to clonality within the same individual. We categorized the ensuing groups according to colonic location to identify differential phenotypes. The SCRC Monoclonal group (M) (19 cases) was divided into Monosegmental (MM) and Pancolonic (MP) groups. The SCRC Polyclonal group (P) (33 cases) was also divided into Monosegmental (PM) and Pancolonic (PP), the first exhibiting preference for left colon. The MM group showed a high rate of mucinous tumors, the lowest mean-number of tumors and associated-polyps, and the worst prognosis. The MP group included the largest mean-number of associated-polyps, best prognosis and familial cancer component. The PM group seemed to be a "frontier" group. Finally, the PP group also exhibited a mucin component, the highest mean-number of tumors (4.6) compared with the mean-number of polyps (7.7), poor prognosis and sporadic cases. Most relevant differential genomic regions within M groups were gains on 1q24 and 8q24, and deletions on 1p21 and 1p23 for MM, while within P were the gains on 7q36 and deletions on 1p36 for PM. The statistical application employed seems to define clonality more accurately in SCRC -more likely to be polyclonal in origin-, and together with the tumor locations, helped us to configure a classification with prognostic and clinical value.


Assuntos
Neoplasias Colorretais/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Neoplasias Primárias Múltiplas/genética , Polimorfismo de Nucleotídeo Único , Sequenciamento Completo do Genoma/métodos , Idoso , Idoso de 80 Anos ou mais , Evolução Clonal , Neoplasias Colorretais/classificação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Primárias Múltiplas/classificação , Prognóstico
13.
Neoplasia ; 19(1): 28-34, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27987438

RESUMO

AIM: To investigate whether chromosomal instability (CIN) is associated with tumor phenotypes and/or with global genomic status based on MSI (microsatellite instability) and CIMP (CpG island methylator phenotype) in early-onset colorectal cancer (EOCRC). METHODS: Taking as a starting point our previous work in which tumors from 60 EOCRC cases (≤45 years at the time of diagnosis) were analyzed by array comparative genomic hybridization (aCGH), in the present study we performed an unsupervised hierarchical clustering analysis of those aCGH data in order to unveil possible associations between the CIN profile and the clinical features of the tumors. In addition, we evaluated the MSI and the CIMP statuses of the samples with the aim of investigating a possible relationship between copy number alterations (CNAs) and the MSI/CIMP condition in EOCRC. RESULTS: Based on the similarity of the CNAs detected, the unsupervised analysis stratified samples into two main clusters (A, B) and four secondary clusters (A1, A2, B3, B4). The different subgroups showed a certain correspondence with the molecular classification of colorectal cancer (CRC), which enabled us to outline an algorithm to categorize tumors according to their CIMP status. Interestingly, each subcluster showed some distinctive clinicopathological features. But more interestingly, the CIN of each subcluster mainly affected particular chromosomes, allowing us to define chromosomal regions more specifically affected depending on the CIMP/MSI status of the samples. CONCLUSIONS: Our findings may provide a basis for a new form of classifying EOCRC according to the genomic status of the tumors.


Assuntos
Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Hibridização Genômica Comparativa , Estudos de Associação Genética , Predisposição Genética para Doença , Fenótipo , Adolescente , Adulto , Carcinoma in Situ/genética , Carcinoma in Situ/patologia , Aberrações Cromossômicas , Análise por Conglomerados , Neoplasias Colorretais/mortalidade , Ilhas de CpG , Metilação de DNA , Feminino , Instabilidade Genômica , Humanos , Estimativa de Kaplan-Meier , Masculino , Instabilidade de Microssatélites , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Regiões Promotoras Genéticas , Adulto Jovem
14.
Clin Colorectal Cancer ; 16(1): 31-37, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27600984

RESUMO

BACKGROUND: Two or more primary colorectal tumors coexisting at the time of diagnosis are considered to be synchronous tumors. It is estimated that synchronous colorectal cancer (SCRC) only accounts for 1.1% to 8.1% of all colorectal cancers (CRCs), and its molecular basis is still poorly understood. PATIENTS AND METHODS: We evaluated the microsatellite instability (MSI) and the CpG island methylator phenotype (CIMP) statuses in a series of 49 patients (98 tumors) diagnosed with sporadic SCRC at the 12 de Octubre University Hospital with the aim of improving the molecular characterization of this type of tumor. We considered Lynch syndrome, familial adenomatous polyposis, and MUTYH-associated polyposis (MAP) as exclusion criteria. RESULTS: Molecular subgrouping on the basis of MSI and CIMP enabled us to define 4 groups that corresponded to the molecular classification proposed for single-tumor CRC. We observed a significant predominance of MSI tumors at the right side regardless of the methylation pattern, and a significant prevalence of microsatellite-stable tumors either at the left side or throughout the entire colon (P = .026). Furthermore, we defined some molecular features frequently observed in sporadic SCRC such as a low-frequency of MSI (8.2%). We observed a high concordance in terms of MSI between simultaneous tumors (93.9%) and a lower concordance in terms of CIMP (51%) between such tumors. CONCLUSION: Our findings support the hypothesis that SCRC involves an environmental rather than a genetic component in which various etiologic factors might modify tumor progression. Further studies are required to refine the molecular characterization of SCRC.


Assuntos
Adenocarcinoma/genética , Neoplasias Colorretais/genética , Ilhas de CpG/genética , Metilação de DNA/genética , Instabilidade de Microssatélites , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino
15.
Oncotarget ; 7(49): 80664-80679, 2016 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-27811368

RESUMO

Multiple myeloma (MM) remains incurable despite the introduction of novel agents, and a relapsing course is observed in most patients. Although the development of genomic technologies has greatly improved our understanding of MM pathogenesis, the mechanisms underlying relapse have been less thoroughly investigated. In this study, an integrative analysis of DNA copy number, DNA methylation and gene expression was conducted in matched diagnosis and relapse samples from MM patients. Overall, the acquisition of abnormalities at relapse was much more frequent than the loss of lesions present at diagnosis, and DNA losses were significantly more frequent in relapse than in diagnosis samples. Interestingly, copy number abnormalities involving more than 100 Mb of DNA at relapse significantly affect the gene expression of these samples, provoking a particular deregulation of the IL-8 pathway. On the other hand, no significant modifications of gene expression were observed in those samples with less than 100 Mb affected by chromosomal changes. Although several statistical approaches were used to identify genes whose abnormal expression at relapse was regulated by methylation, only two genes that were significantly deregulated in relapse samples (SORL1 and GLT1D1) showed a negative correlation between methylation and expression. Further analysis revealed that DNA methylation was involved in regulating SORL1 expression in MM. Finally, relevant changes in gene expression observed in relapse samples, such us downregulation of CD27 and P2RY8, were most likely not preceded by alterations in the corresponding DNA. Taken together, these results suggest that the genomic heterogeneity described at diagnosis remains at relapse.


Assuntos
Biomarcadores Tumorais/genética , Biologia Computacional/métodos , Variações do Número de Cópias de DNA , Metilação de DNA , Dosagem de Genes , Regulação Neoplásica da Expressão Gênica , Mieloma Múltiplo/genética , Integração de Sistemas , Linhagem Celular Tumoral , Bases de Dados Genéticas , Perfilação da Expressão Gênica/métodos , Estudos de Associação Genética , Predisposição Genética para Doença , Glicosiltransferases/genética , Humanos , Proteínas Relacionadas a Receptor de LDL/genética , Proteínas de Membrana Transportadoras/genética , Mieloma Múltiplo/patologia , Mieloma Múltiplo/terapia , Análise de Sequência com Séries de Oligonucleotídeos , Fenótipo , Polimorfismo de Nucleotídeo Único , Receptores Purinérgicos P2Y/genética , Recidiva , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/genética
16.
PLoS One ; 11(10): e0164370, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27741277

RESUMO

To explore novel genetic abnormalities occurring in myelodysplastic syndromes (MDS) through an integrative study combining array-based comparative genomic hybridization (aCGH) and next-generation sequencing (NGS) in a series of MDS and MDS/myeloproliferative neoplasms (MPN) patients. 301 patients diagnosed with MDS (n = 240) or MDS/MPN (n = 61) were studied at the time of diagnosis. A genome-wide analysis of DNA copy number abnormalities was performed. In addition, a mutational analysis of DNMT3A, TET2, RUNX1, TP53 and BCOR genes was performed by NGS in selected cases. 285 abnormalities were identified in 71 patients (23.6%). Three high-risk MDS cases (1.2%) displayed chromothripsis involving exclusively chromosome 13 and affecting some cancer genes: FLT3, BRCA2 and RB1. All three cases carried TP53 mutations as revealed by NGS. Moreover, in the whole series, the integrative analysis of aCGH and NGS enabled the identification of cryptic recurrent deletions in 2p23.3 (DNMT3A; n = 2.8%), 4q24 (TET2; n = 10%) 17p13 (TP53; n = 8.5%), 21q22 (RUNX1; n = 7%), and Xp11.4 (BCOR; n = 2.8%), while mutations in the non-deleted allele where found only in DNMT3A (n = 1), TET2 (n = 3), and TP53 (n = 4). These cryptic abnormalities were detected mainly in patients with normal (45%) or non-informative (15%) karyotype by conventional cytogenetics, except for those with TP53 deletion and mutation (15%), which had a complex karyotype. In addition to well-known copy number defects, the presence of chromothripsis involving chromosome 13 was a novel recurrent change in high-risk MDS patients. Array CGH analysis revealed the presence of cryptic abnormalities in genomic regions where MDS-related genes, such as TET2, DNMT3A, RUNX1 and BCOR, are located.


Assuntos
Aberrações Cromossômicas , Síndromes Mielodisplásicas/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Cromossomos Humanos Par 13 , Hibridização Genômica Comparativa , Subunidade alfa 2 de Fator de Ligação ao Core/genética , DNA/química , DNA/isolamento & purificação , DNA/metabolismo , DNA (Citosina-5-)-Metiltransferases/genética , Variações do Número de Cópias de DNA , DNA Metiltransferase 3A , Análise Mutacional de DNA , Proteínas de Ligação a DNA/genética , Dioxigenases , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Cariótipo , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/diagnóstico , Síndromes Mielodisplásicas/patologia , Proteínas Proto-Oncogênicas/genética , Recidiva , Risco , Proteína Supressora de Tumor p53/genética , Adulto Jovem
17.
Br J Haematol ; 172(3): 428-38, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26567765

RESUMO

The introduction of Rituximab has improved the outcome and survival rates of Burkitt lymphoma (BL). However, early relapse and refractoriness are current limitations of BL treatment and new biological factors affecting the outcome of these patients have not been explored. This study aimed to identify the presence of genomic changes that could predict the response to new therapies in BL. Forty adolescent and adult BL patients treated with the Dose-Intensive Chemotherapy Including Rituximab (Burkimab) protocol (Spanish Programme for the Study and Treatment of Haematological Malignancies; PETHEMA) were analysed using array-based comparative genomic hybridization (CGH). In addition, the presence of TP53, TCF3 (E2A), ID3 and GNA13 mutations was assessed by next-generation sequencing (NGS). Ninety-seven per cent of the patients harboured genomic imbalances. Losses on 11q, 13q, 15q or 17p were associated with a poor response to Burkimab therapy (P = 0·038), shorter progression-free survival (PFS; P = 0·007) and overall survival (OS; P = 0·009). The integrative analysis of array-CGH and NGS showed that 26·3% (5/19) and 36·8% (7/19) of patients carried alterations in the TP53 and TCF3 genes, respectively. TP53 alterations were associated with shorter PFS (P = 0·011) while TCF3 alterations were associated with shorter OS (P = 0·032). Genetic studies could be used for risk stratification of BL patients treated with the Burkimab protocol.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfoma de Burkitt/tratamento farmacológico , Linfoma de Burkitt/genética , Aberrações Cromossômicas , Adolescente , Adulto , Idoso , Hibridização Genômica Comparativa/métodos , Feminino , Genoma , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Rituximab/administração & dosagem , Resultado do Tratamento , Adulto Jovem
18.
Mol Carcinog ; 55(5): 705-16, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-25808986

RESUMO

Chromosomal instability resulting in copy number alterations is a hallmark of colorectal cancer (CRC). However, few studies have attempted to characterize the chromosomal changes occurring in early-onset CRC in order to compare them with those taking place within the more extensively studied late-onset CRC subset. Our aim was to characterize the genomic profiles of these two groups of colorectal tumors and to compare them to each other. Array comparative genomic hybridization profiling of 146 colorectal tumors (60 early-onset and 86 late-onset) in combination with an unsupervised analysis was used to define common and specific copy number alterations. We found a number of important differences between the chromosomal instability profiles of each age subset. Thus, losses at 1p36, 1p12, 1q21, 9p13, 14q11, 16p13, and 16p12 were significantly more frequent in younger patients, whereas gains at 7q11 and 7q22 were more frequent in older patients. Moreover, the unsupervised analysis stratified the tumors into two clusters, each one of which was enriched in patients from one of the age subsets. Our findings confirm the existence of substantial differences between the chromosomal instability profiles of the two groups which are more important from a qualitative point of view. Further studies are needed to understand the clinicopathological implications of these dissimilarities.


Assuntos
Instabilidade Cromossômica , Neoplasias Colorretais/genética , Hibridização Genômica Comparativa/métodos , Variações do Número de Cópias de DNA , Adolescente , Adulto , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/patologia , Feminino , Humanos , Masculino , Adulto Jovem
19.
Am J Cancer Res ; 5(7): 2308-13, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26328262

RESUMO

Early-onset Colorectal Cancer (ECRC) represents a significant and increasing proportion of Colorectal Cancer (CRC), but it is a heterogeneous entity that probably encompasses specific subclasses. On the premise that the carcinogenetic mechanism and progression of CRC may differ with location, we analyzed molecular and clinical characteristics of ECRC according to tumor location in order to identify more homogeneous subgroups of CRC. Right-sided ECRC is a subset in which most Lynch Syndrome cases are found, with earlier stages at diagnosis and better prognosis. At this location the CpG Island Methylator Phenotype (CIMP) is predominant and Chromosomal Instability (CI) is rare. Left-sided ECRC appears as a transitional or intermediate location, except for CI tumors, that seem to predominate at this location. Finally, rectal ECRC shows Microsatellite Stability, CIMP low-0 and low CI - with recurrent altered chromosomal regions in common with left-sided ECRC-, possibly in relation with Microsatellite And Chromosomal Stable tumors, but with an unexpected familial component and worse prognosis. All this suggest that the molecular basis of ECRC varies with tumor location, which could affect the clinical management of patients.

20.
BMC Clin Pathol ; 13(1): 23, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-24079673

RESUMO

BACKGROUND: Malignant astrocytomas are the most common primary brain tumors and one of the most lethal among human cancers despite optimal treatment. Therefore, the characterization of molecular alterations underlying the aggressive behavior of these tumors and the identification of new markers are thus an important step towards a better patient stratification and management. METHODS AND RESULTS: VRK1 and VRK2 (Vaccinia-related kinase-1, -2) expression, as well as proliferation markers, were determined in a tissue microarray containing 105 primary astrocytoma biopsies. Kaplan Meier and Cox models were used to find clinical and/or molecular parameters related to overall survival. The effects of VRK protein levels on proliferation were determined in astrocytoma cell lines. High levels of both protein kinases, VRK1 or VRK2, correlated with proliferation markers, p63 or ki67. There was no correlation with p53, reflecting the disruption of the VRK-p53-DRAM autoregulatory loop as a consequence of p53 mutations. High VRK2 protein levels identified a subgroup of astrocytomas that had a significant improvement in survival. The potential effect of VRK2 was studied by analyzing the growth characteristics of astrocytoma cell lines with different EGFR/VRK2 protein ratios. CONCLUSION: High levels of VRK2 resulted in a lower growth rate suggesting these cells are more indolent. In high-grade astrocytomas, VRK2 expression constitutes a good prognostic marker for patient survival.

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