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2.
Pulmonology ; 26(1): 10-17, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31630986

RESUMO

OBJECTIVE: The main aim of the study was to evaluate the efficacy and safety profile of Nivolumab, an immune-checkpoint-inhibitor antibody, in advanced, previously treated, Non-Small Cell Lung Cancer (NSCLC) patients, in a real world setting. METHODS: We performed a retrospective, multicentre data analysis of patients who were included in the Portuguese Nivolumab Expanded Access Program (EAP). Eligibility criteria included histologically or citologically confirmed NSCLC, stage IIIB and IV, evaluable disease, sufficient organ function and at least one prior line of chemotherapy. The endpoints included Overall Response Rate (ORR), Disease Control Rate (DCR), Progression Free Survival (PFS) and Overall Survival (OS). Safety analysis was performed with the National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE), version 4.0, and immune-related Adverse Events (irAEs) were treated according to protocol treatment guidelines. Tumour response was assessed using the Response Evaluation Criteria in Solid Tumours (RECIST) version 1.1. Data was analysed using SPSS, version 21.0 (IBM Statistics). RESULTS: From June 2015 to December 2016, a total of 229 patients with advanced NSCLC were enrolled at 30 Portuguese centres. Clinical data were collected up to the end of July 2018. The baseline median age was 64 years (range 37-83) and the majority of patients were males (70.3%) and former/current smokers (69.4%). Patients with non-squamous histology predominated (88.1%), and 67.6% of the patients had received 2 or more prior lines of chemotherapy. Out of 229 patients, data was available for 219 patients (3 patients did not start treatment, while data was unavailable in 7 patients); of the 219 patients, 15.5% were not evaluated for radiological tumour assessment, 1.4% had complete response (CR), 21% partial response (PR), 31% stable disease (SD) and 31.1% progressive disease (PD). Thus, the ORR was 22.4% and DCR was 53.4% in this population. At the time of survival analysis the median PFS was 4.91 months (95% CI, 3.89-6.11) and median OS was 13.21 months (95% CI, 9.89-16.53). The safety profile was in line with clinical trial data. CONCLUSIONS: Efficacy and safety results observed in this retrospective analysis were consistent with observations reported in clinical trials and from other centres.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Nivolumabe/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Imunológicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/epidemiologia , Feminino , Humanos , Incidência , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/epidemiologia , Masculino , Pessoa de Meia-Idade , Portugal/epidemiologia , Intervalo Livre de Progressão , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Resultado do Tratamento
3.
Neotrop Entomol ; 47(5): 598-609, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28971341

RESUMO

We report on Asphondylia poss. swaedicola Kieffer & Jörgensen inducing apical stem galls on Suaeda divaricata Moquin-Tandon in the Monte region of Argentina. The putative inquiline gelechiid Scrobipalpula patagonica Povolný is confirmed as an associate of A. poss. swaedicola galls. The following hymenopteran parasitoids are associated with this system: Torymus nr swaedicola (Kieffer & Jörgensen), Aprostocetus sp., Horismenus sp., Bracon (Bracon) sp., Chelonus (Microchelonus) sp., Apanteles sp., Zaeucoila robusta (Ashmead), and Goniozus nigrifemur Ashmead. The Horismenus sp., Z. robusta, and G. nigrifemur are reported as associates of Suaeda for the first time. A total of 28 genera and 31 species of parasitoids known to be associated with Suaeda spp. worldwide and their associations are tabulated.


Assuntos
Chenopodiaceae , Dípteros/parasitologia , Himenópteros , Lepidópteros/parasitologia , Tumores de Planta , Animais , Argentina , Interações Hospedeiro-Parasita
4.
Clin Genet ; 76(3): 242-55, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19793053

RESUMO

Patients presenting familial adenomatous polyposis (FAP), attenuated familial adenomatous polyposis (AFAP) or multiple colorectal adenomas (MCRAs) phenotype are clinically difficult to distinguish. We aimed to genetically characterize 107 clinically well-characterized patients with FAP-like phenotype, and stratified according to the recent guidelines for the clinical management of FAP: FAP, AFAP, MCRA (10-99 colorectal adenomas) without family history of colorectal cancer or few adenomas (FH), MCRA (10-99) with FH, MCRA (3-9) with FH. Overall, APC or MUTYH mutations were detected in 42/48 (88%), 14/20 (70%) and 10/38 (26%) of FAP, AFAP and MCRA patients, respectively. APC and MUTYH mutations accounted for 81% and 7% of FAP patients and for 30% and 40% of AFAP patients, respectively. Notably, MCRA patients did not present APC mutations. In 26% of these patients, an MUTYH mutation was identified and the detection rate increased with the number of adenomas, irrespectively of family history, being significantly higher in MCRA patients presenting more than 30 adenomas [7/12 (58%) vs 2/14 (14%), p = 0.023]. We validate the recently proposed guidelines in our patient's cohort and show that APC or MUTYH germline defects are responsible for the majority of clinically well-characterized patients with FAP and AFAP phenotype, and patients with more than 30 colorectal adenomas. The different mutation frequencies according to family history and to the number of adenomas underscore the importance of an adequate familial characterization, both clinically and by colonoscopy, in the management of FAP-like phenotypes. The phenotypes of the mutation-negative patients suggest distinct etiologies in these cases.


Assuntos
Adenoma/enzimologia , Adenoma/genética , Proteína da Polipose Adenomatosa do Colo/genética , Polipose Adenomatosa do Colo/enzimologia , Polipose Adenomatosa do Colo/genética , DNA Glicosilases/genética , Mutação/genética , Adolescente , Adulto , Idoso , Alelos , Estudos de Coortes , Neoplasias Colorretais/genética , Análise Mutacional de DNA , Família , Testes Genéticos , Humanos , Pessoa de Meia-Idade , Fenótipo
5.
Am J Gastroenterol ; 99(9): 1779-84, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15330918

RESUMO

BACKGROUND: Hyperplastic polyposis (HP) is a rare condition characterized by the presence of multiple hyperplastic polyps in the colon, which has been associated to an increased risk of colorectal cancer (CRC). Guidelines for management of this disease remain, so far, undefined. AIMS: To evaluate, in symptomatic patients with HP, phenotypic characteristics as well as results of a screening program in their at-risk first-degree relatives. PATIENTS: Pedigree information and clinical and endoscopic data of 14 patients with HP was studied. SEVENTEEN AND METHODS: at-risk first-degree relatives from six families were also invited to perform screening colonoscopy. RESULTS: Twelve of fourteen (86%) patients had fewer than 100 colorectal polyps. Polyps' sizes ranged from 2 to 25 mm and were uniformly distributed through the whole colon in 43% of the patients. Hyperplastic polyps predominated, but 11/14 (79%) patients also harbored serrated as well as classic adenomatous polyps. CRC was present in 6/14 (43%) of the patients at the time of diagnosis. Familial history of CRC/polyps was positive in 6/12 (50%) of cases. Colonoscopy in at-risk relatives disclosed polyps in 10/17 (59%) of cases with at least one additional patient having criteria for HP. CONCLUSIONS: Although small, this series demonstrates that a high level of suspicion is needed to diagnose the HP syndrome, in which serrated adenomas seem to be the hallmark. Although an elevated percentage of CRC was observed in this series of symptomatic patients with HP, prospective studies in asymptomatic individuals are needed to clearly quantify the risk of CRC in patients with HP. Because familial aggregation of HP was present in 3/12 (25%) of kindreds, screening colonoscopy should be offered to first-degree relatives.


Assuntos
Polipose Adenomatosa do Colo/patologia , Polipose Adenomatosa do Colo/terapia , Neoplasias Colorretais/prevenção & controle , Predisposição Genética para Doença/epidemiologia , Testes Genéticos/normas , Guias de Prática Clínica como Assunto , Polipose Adenomatosa do Colo/epidemiologia , Adulto , Distribuição por Idade , Idoso , Estudos de Coortes , Colonoscopia , Neoplasias Colorretais/patologia , Feminino , Seguimentos , Testes Genéticos/tendências , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Linhagem , Portugal/epidemiologia , Medição de Risco , Índice de Gravidade de Doença , Distribuição por Sexo
7.
Gut ; 50(3): 405-12, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11839723

RESUMO

BACKGROUND: In hereditary non-polyposis colorectal cancer, over 90% of the identified mutations are in two genes, hMSH2 and hMLH1. A large proportion of the mutations detected in these genes are of the missense type which may be either deleterious mutations or harmless polymorphisms. AIM: To investigate whether nine missense and one splice site mutation of hMLH1 and hMSH2, in 10 kindreds with a familial history of colorectal cancer or young age of onset, could be interpreted as pathogenic. METHODS: Clinical and genetic characteristics were collected: (i) evolutionary conservation of the codon involved; (ii) type of amino acid change; (iii) occurrence of mutation in healthy controls; (iv) cosegregation of mutation with disease phenotype; (v) functional consequences of gene variant; and (vi) microssatellite instability and immunoexpression of hMSH2 and hMLH1 analysis. RESULTS: Seven different missense and one splice site mutation were identified. Only 1/8 was found in the control group, 2/7 occurred in conserved residues, and 5/7 resulted in non-conservative changes. Functional studies were available for only 2/8 mutations. Segregation of the missense variant with disease phenotype was observed in three kindreds. CONCLUSION: In the majority of families included, there was no definitive evidence that the missense or splice site alterations were causally associated with an increased risk of developing colorectal cancer. Until further evidence is available, these mutational events should be regarded and interpreted carefully and genetic diagnosis should not be offered to these kindreds.


Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/genética , Proteínas de Ligação a DNA , Mutação de Sentido Incorreto , Proteínas de Neoplasias/genética , Proteínas Proto-Oncogênicas/genética , Sítios de Splice de RNA/genética , Proteínas Adaptadoras de Transdução de Sinal , Adulto , Proteínas de Transporte , Feminino , Predisposição Genética para Doença , Testes Genéticos/métodos , Humanos , Masculino , Repetições de Microssatélites/genética , Pessoa de Meia-Idade , Proteína 1 Homóloga a MutL , Proteína 2 Homóloga a MutS , Proteínas Nucleares , Linhagem , RNA Neoplásico/genética
8.
Proc Natl Acad Sci U S A ; 99(5): 2954-8, 2002 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-11867715

RESUMO

Familial adenomatous polyposis (FAP) is a dominantly inherited colorectal tumor predisposition that results from germ-line mutations in the APC gene (chromosome 5q21). FAP shows substantial phenotypic variability: classical polyposis patients develop more than 100 colorectal adenomas, whereas those with attenuated polyposis (AAPC) have fewer than 100 adenomas. A further group of individuals, so-called "multiple" adenoma patients, have a phenotype like AAPC, with 3-99 polyps throughout the colorectum, but mostly have no demonstrable germ-line APC mutation. Routine mutation detection techniques fail to detect a pathogenic APC germ-line mutation in approximately 30% of patients with classical polyposis and 90% of those with AAPC/multiple adenomas. We have developed a real-time quantitative multiplex PCR assay to detect APC exon 14 deletions. When this technique was applied to a set of 60 classical polyposis and 143 AAPC/multiple adenoma patients with no apparent APC germ-line mutation, deletions were found exclusively in individuals with classical polyposis (7 of 60, 12%). Fine-mapping of the region suggested that the majority (6 of 7) of these deletions encompassed the entire APC locus, confirming that haploinsufficiency can result in a classical polyposis phenotype. Screening for germ-line deletions in APC mutation-negative individuals with classical polyposis seems warranted.


Assuntos
Proteína da Polipose Adenomatosa do Colo/genética , Polipose Adenomatosa do Colo/genética , Genes APC/fisiologia , Adenoma/genética , Neoplasias Colorretais/genética , Primers do DNA , Éxons , Deleção de Genes , Testes Genéticos/métodos , Humanos , Reação em Cadeia da Polimerase/métodos
9.
Gynecol Oncol ; 82(2): 223-8, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11531271

RESUMO

OBJECTIVE: Hereditary nonpolyposis colorectal cancer (HNPCC) is a hereditary cancer susceptibility disorder associated with a very high risk for carcinoma of the colon and an elevated risk for certain extracolonic cancers including ovarian cancer. Our aim in this study was to describe the clinicopathologic features of ovarian cancer in HNPCC family members. METHODS: . Members of the International Collaborative Group on HNPCC collected retrospective data on 80 ovarian cancer patients who were members of HNPCC families, including 31 known mutation carriers, 35 presumptive carriers (by colorectal/endometrial cancer status), and 14 at-risk family members. RESULTS: Mean age at diagnosis of ovarian cancer was 42.7. Nonepithelial tumors made up only 6.4% of the cancers, and borderline tumors comprised just 4.1% of the epithelial cancers. Among frankly malignant epithelial cases, most cancers were well or moderately differentiated, and 85% were FIGO stage I or II at diagnosis. Synchronous endometrial cancer was reported in 21.5% of cases. CONCLUSIONS: Ovarian cancer in HNPCC differs from ovarian cancer in the general population in several clinically important respects. It occurs at a markedly earlier age. It is more likely to be epithelial. If it is a frankly invasive epithelial cancer, it is more likely to be well or moderately differentiated. HNPCC patients with ovarian cancer are more likely to have a synchronous endometrial cancer than other ovarian cancer patients and are more likely to be diagnosed at an early stage.


Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/genética , Neoplasias Colorretais Hereditárias sem Polipose/patologia , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Adulto , Fatores Etários , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Primárias Múltiplas/genética , Neoplasias Primárias Múltiplas/patologia , Segunda Neoplasia Primária/genética , Segunda Neoplasia Primária/patologia , Estudos Retrospectivos
12.
Eur J Hum Genet ; 8(1): 49-53, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10713887

RESUMO

Mutation searching was performed in the hMSH2 and hMLH1 genes in 20 Portuguese families representing 124 registered affected individuals. Of the 20, 16 fulfilled the classic 'Amsterdam' criteria for HNPCC, whereas the remaining four families satisfied a modified set of criteria. These criteria required a CRC diagnosed before age 50 years and cancers diagnosed in two other relatives within the HNPCC spectrum. A multi-method approach was performed using the protein truncation test (PTT), single strand conformation polymorphism (SSCP) with two different sets of conditions, heteroduplex analysis (HA) and denaturing gradient gel electrophoresis (DGGE). Putative phenotype-genotype correlations were also explored. Ten different germline mutations were identified. Six of these were found in hMLH1 in seven families and four in hMSH2 in four families. SSCP and DGGE had the highest diagnostic yields with the percentage of variants detected above 67% and together HA and PTT had the lowest. No single technique detected all variants. Trends for the absence of extracolonic manifestations were observed in families carrying hMLH1 germline mutations (four of seven in hMLH1 vs one of four in hMSH2). Most of the families with rectal cancer were associated with hMLH1 (six of seven in hMLH1 vs two of four in hMSH2). A multi-technique approach is necessary to identify a high percentage of germline mutations. Seven novel mutations were found in this Portuguese population.


Assuntos
Pareamento Incorreto de Bases , Neoplasias Colorretais Hereditárias sem Polipose/genética , Reparo do DNA , Proteínas de Ligação a DNA , Proteínas de Neoplasias/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Adaptadoras de Transdução de Sinal , Proteínas de Transporte , DNA/análise , DNA/sangue , Análise Mutacional de DNA/métodos , Feminino , Humanos , Masculino , Proteína 1 Homóloga a MutL , Proteína 2 Homóloga a MutS , Proteínas Nucleares , Polimorfismo Conformacional de Fita Simples , Portugal , RNA/análise , RNA/sangue
13.
Genes Chromosomes Cancer ; 26(4): 372-5, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10534773

RESUMO

Germline mutations that give rise to premature termination codons in mRNAs have frequently been associated with aberrant processing of the nascent transcripts. This can take the form either of nonsense-mediated mRNA decay or of aberrant splicing of the pre-mRNA. In a family affected by hereditary nonpolyposis colorectal cancer, a two-nucleotide deletion in codon 659, which introduces a frameshift and a new stop codon in exon 17 of the DNA mismatch repair gene MLH1, has been reported to lead to skipping of the exon. We now report that this phenomenon occurs also when there are missense or nonsense mutations in this codon. Our results thus suggest that in aberrant splicing the nature of the mutation may be less important than its position within the exon. These findings are of importance to mutation interpretation, as they imply that aberrant splicing could be associated even with silent mutations that do not lead to amino acid substitutions. Genes Chromosomes Cancer 26:372-375, 1999.


Assuntos
Processamento Alternativo/genética , Códon/genética , Neoplasias Colorretais Hereditárias sem Polipose/genética , Mutação de Sentido Incorreto/genética , Proteínas de Neoplasias/genética , Proteínas Adaptadoras de Transdução de Sinal , Proteínas de Transporte , Análise Mutacional de DNA , DNA Complementar/análise , DNA de Neoplasias/análise , Humanos , Linfócitos/química , Proteína 1 Homóloga a MutL , Proteínas Nucleares , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos
14.
Eur J Cancer Prev ; 8(4): 305-10, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10493305

RESUMO

The prooxidant/antioxidant imbalance in familial adenomatous polyposis (FAP) is suggested by (i) the intimate connection between APC and prostaglandin H synthase-2 genes, (ii) the increase of the free radical-generating enzyme xanthine oxidase, and (iii) the decrease of antioxidant defences. In this research work we evaluated lipid peroxidation measuring the thiobarbituric acid (TBA) reactive products and we studied the activities of superoxide dismutase (SOD) and catalase as well as the levels of ascorbate and tocopherols in the peripheral blood cells from a total of 27 FAP patients and 83 normal controls. TBA-reactive products were determined according to a previously published method. SOD and catalase activities were determined by the spectrophotometric monitoring of the inhibition of pyrogallol autoxidation and the hydrogen peroxide decomposition rate, respectively. Ascorbate levels were determined by a modified 2,4-dinitrophenylhydrazine method and tocopherol levels by a modified Emmerie-Engle method. The levels of TBA-reactive products were higher in FAP patients than in normal controls. Although no statistically significant differences in SOD and catalase activities were observed between FAP patients and normal controls, we found that ascorbate and tocopherol levels were significantly lower in FAP patients than in normal controls, as assessed by the Mann-Whitney test. Hence, this finding of an imbalance in the prooxidant/antioxidant status may contribute towards new strategies for prevention and therapy in FAP patients.


Assuntos
Polipose Adenomatosa do Colo/sangue , Biomarcadores Tumorais/sangue , Malondialdeído/sangue , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Adolescente , Adulto , Ácido Ascórbico/sangue , Saúde da Família , Humanos , Peroxidação de Lipídeos , Pessoa de Meia-Idade , Vitamina E/sangue
15.
J Pathol ; 188(3): 252-7, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10419591

RESUMO

Microsatellite instability (MSI) is present in most colorectal cancers (CRC) associated with hereditary nonpolyposis colorectal cancer (HNPCC). MSI testing in so-called sporadic forms of CRC may become a useful tool in identifying new HNPCC kindred. The aim of this study was to analyse the utility of BAT-26 as a marker to identify CRCs with MSI and to investigate whether sporadic CRCs with MSI have a phenotypic expression similar to HNPCC cases. MSI was detected using two methods, an association of 7 poly(CA) repeats and a poly(A) repeat alone, BAT-26, in a series of 62 patients with apparently sporadic forms of CRC. Germ-line and somatic mutations in the hMSH2, hMLH1, and hMSH6 genes were analysed in patients with MSI+ tumours. Patients with MSI+ at poly(CA) loci and at BAT-26 were younger (p=0.024 and p=0.002), had tumours more frequently right sided (p=0.017 and p=0.0001) and more often mucinous (p=0.037 and p=0.005, respectively) than patients with MSI negative tumours. Mutation analysis allowed the identification of two patients carrying germ-line mutations in the hMLH1 gene (both were BAT-26+) and two other patients who had somatic mutation in the hMSH2 and in hMLH1 genes. In conclusion, the detection of MSI using poly(CA) repeats or BAT-26 alone allowed the identification of a subset of patients with clinico-pathological characteristics similar to those associated to HNPCC. BAT-26 has the advantage of being a simple and less expensive method that might be used as a screening procedure before mutation analysis.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias Colorretais/genética , Reparo do DNA , Repetições de Microssatélites/genética , Mutação , Adulto , Idoso , Idoso de 80 Anos ou mais , Pareamento Incorreto de Bases/genética , Neoplasias Colorretais/patologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo
16.
Dis Colon Rectum ; 42(6): 788-95; discussion 795-6, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10378604

RESUMO

PURPOSE: Short chain fatty acids are the main energy source of colonocytes and their use may be impaired in chronic radiation proctitis. The aim of the present study was to evaluate the therapeutic effect of short chain fatty acid enemas in patients with chronic radiation proctitis. METHODS: A prospective, randomized, double-blind trial comparing short chain fatty acid enemas with placebo was conducted in 19 patients with chronic radiation proctitis. Short chain fatty acid enemas contained 60 mM sodium acetate, 30 mM sodium propionate, and 40 mM sodium butyrate. The treatment period lasted five weeks and patients were followed up for six months. RESULTS: On admission, both groups were similar regarding all parameters evaluated. After five weeks short chain fatty acid-treated patients showed a significant decrease in the number of days with rectal bleeding from the previous week (4.4+/-1.8 to 1.4+/-2.2; P = 0.001) and an improvement of endoscopic score (4.8+/-1.4 to 2.2+/-1.2; P = 0.001). Hemoglobin values were also significantly higher in short chain fatty acid-treated patients (13.1+/-0.9 g/dl vs. 10.7+/-2.1 g/dl; P = 0.02). Mucosal DNA and protein concentrations decreased in both groups but significantly so only in placebo-treated patients (P = 0.05). Changes in histologic parameters were not significant in either group. Although short chain fatty acid-treated patients did not get worse in the next six months, placebo-treated ones gradually improved, and at the end of six months, differences between the two groups were no longer observed. CONCLUSIONS: Short chain fatty acid enemas can accelerate the process of healing in chronic radiation proctitis, but treatment has to be continuous if a complete and sustained clinical, endoscopic, and histologic response is to be obtained.


Assuntos
Ácidos Graxos Voláteis/uso terapêutico , Proctite/tratamento farmacológico , Lesões por Radiação/tratamento farmacológico , Doença Crônica , Método Duplo-Cego , Enema , Ácidos Graxos Voláteis/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proctite/etiologia , Estudos Prospectivos , Fatores de Tempo
17.
Cancer Genet Cytogenet ; 111(2): 152-6, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10347554

RESUMO

Germ-line mutations in the adenomatous polyposis coli (APC) gene are responsible for familial adenomatous polyposis (FAP). In the present study, we have used the protein truncation test to screen for mutations in exon 15 and exons 1-14 of the APC gene and denaturing gradient gel electrophoresis to analyze exons 1-14. We have studied nine unrelated FAP kindreds, eight with the classical phenotype and one with an atypical phenotype, with several family members exhibiting fewer than 50 colonic polyps. The combined use of these two methodologies allowed the identification of seven novel mutations, with two unrelated families sharing the same mutation. All mutations were chain terminating: six resulted from small deletions, one from a small insertion, and one was a point mutation, resulting in a premature stop codon. Seven mutations were located in exon 15 of the APC gene, one was in exon 10, and the remaining one, which corresponded to the kindred with an atypical phenotype, was located in exon 4.


Assuntos
Polipose Adenomatosa do Colo/genética , Proteínas do Citoesqueleto/genética , Genes APC , Mutação , Proteína da Polipose Adenomatosa do Colo , Proteínas do Citoesqueleto/metabolismo , Análise Mutacional de DNA , Eletroforese/métodos , Feminino , Humanos , Masculino , Linhagem , Fenótipo , Portugal
18.
Cancer ; 85(4): 779-85, 1999 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-10091754

RESUMO

BACKGROUND: Colorectal tumors with microsatellite instability (MSI) that do not comply with previously defined clinical criteria may be found in recently diagnosed hereditary nonpolyposis colorectal carcinoma families. Until recently, the indications for MSI testing were not clearly established. The objective of the current study was to validate the recently published Bethesda guidelines for MSI testing in a series of patients with apparently sporadic forms of colorectal carcinoma (CRC). METHODS: Sixty-two patients with so-called sporadic CRC were included in the current study. MSI was analyzed at seven poly(CA) repeat sequences and at one poly(A) locus. RESULTS: Nine of 62 patients (14.5%) had tumors exhibiting MSI at > or = 2 loci and 7 patients (11%) had MSI at > or = 3 loci. Patients with MSI positive tumors were younger (P < 0.05), and their tumors more frequently were right-sided (P < 0.02) and more often exhibited a mucinous component (P < 0.05). The Bethesda guidelines were positive in 18% (11 of 62) of patients. The sensitivity of these guidelines in identifying tumors with MSI at > or = 3 loci was 43% and the positive predictive value (PPV) was 27% (3 of 11 cases). Other variables were considered as alternative criteria to identify CRCs with MSI: age < 45 years and/or a right-sided tumor with a mucinous component. Using these 2 criteria alone, sensitivity increased to 85% and PPV to 46%. CONCLUSIONS: In this study group, the use of three clinical criteria as sole indicators for MSI testing in patients with apparently sporadic forms of CRC were significantly more discriminating compared with the Bethesda guidelines, in addition to being substantially easier.


Assuntos
Neoplasias do Colo/genética , Guias como Assunto , Repetições de Microssatélites/genética , Neoplasias Retais/genética , Adenocarcinoma Mucinoso/genética , Adenocarcinoma Mucinoso/patologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Colo/patologia , Feminino , Marcadores Genéticos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Retais/patologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
19.
Am J Gastroenterol ; 93(10): 1991-2, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9772075

RESUMO

It remains debatable whether young patients with colorectal tumors should undergo genetic testing with the aim of identifying new hereditary nonpolyposis colorectal cancer families. We describe a case of a young woman with colon cancer with no clinical criteria of hereditary nonpolyposis colorectal cancer, whose genetic analysis showed that the tumor displayed microsatellite instability, and in whom a truncated protein in hMSH2 gene was found, which was also present in two at-risk relatives.


Assuntos
Neoplasias do Colo/genética , Neoplasias Colorretais Hereditárias sem Polipose/genética , Reparo do DNA/genética , Proteínas de Ligação a DNA , Repetições de Microssatélites , Adulto , Feminino , Humanos , Proteína 2 Homóloga a MutS , Mutação , Linhagem , Proteínas Proto-Oncogênicas/genética , Fatores de Risco
20.
Am J Gastroenterol ; 93(9): 1572-4, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9732950

RESUMO

The Muir-Torre syndrome is a rare autosomal dominant disorder characterized by the association of visceral malignancies with typical skin lesions. This syndrome is now considered a subtype of the more common hereditary nonpolyposis colorectal cancer syndrome (HNPCC). This last condition has been ascribed to mutations in four mismatch repair genes, and similar mutations, mostly located at hMSH2 gene, are now being described in some Muir-Torre patients. We describe the case of a 64-yr-old woman with no family history of colorectal cancer, who developed two visceral malignancies belonging to the usual spectrum of hereditary nonpolyposis colorectal cancer (colon and stomach), beginning at age 41. She additionally developed several skin tumors, including multiple keratoacanthomas, thus fulfilling Muir-Torre diagnostic criteria. Because of her cutaneous phenotype, she was screened for DNA mismatch repair gene mutations by in vitro synthetized protein assay (IVSP) and a truncating mutation was identified at hMSH2. We further discuss the clinical significance of the Muir-Torre phenotype, the association of this syndrome with hMSH2 mutations and the important implications of genetic diagnosis for the patient and her offspring.


Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/genética , Proteínas de Ligação a DNA , Proteínas de Neoplasias/genética , Neoplasias Primárias Múltiplas/genética , Proteínas Proto-Oncogênicas/genética , Neoplasias Cutâneas/genética , Feminino , Humanos , Pessoa de Meia-Idade , Proteína 2 Homóloga a MutS , Fenótipo , Síndrome
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