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1.
J Asthma ; 59(1): 23-30, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-32962473

RESUMEN

Background: Although the etiology and disease mechanisms of asthma and alpha-1 antitrypsin deficiency (AATD) are distinct, several reports indicate that asthma is common in AATD patients, however the relationships between asthma and AATD are poorly described in the literature.Objectives: The aim of the study was to investigate in a cohort of outpatients affected by mild to moderate asthma the clinical features that may differentiate asthmatic patients with and without mutation on SERPINA1 gene.Methods: Seven hundred thirty-five asthmatic outpatients underwent quantitative analysis of the serum level of alpha-1antitrypsin. According to the literature only sixty-seven out of seven hundred thirty-five asthmatic patients were submitted to genetic analysis to identify AATD and non-AATD subjects. Fifty-eight patients were studied. Clinical and functional data, including lung function, atopy and bronchial hyperactivity, were recorded.Results: The fifty-eight asthmatic patients were divided in AATD patients (n = 22) and non AATD patients (n = 36), according to genotype. The presence of atopy was significantly higher in patients with AATD than in those without AATD (91% vs. 64%; p = 0.031). AATD patients reported allergic manifestations more than non AATD patients (77% vs. 47%; p = 0.030).Conclusion: Our study shows that the presence of atopy in asthmatic patients with AATD is significantly higher than in asthmatic patients without gene mutation. In addition, a higher percentage of AATD patients self-reported allergic manifestations. No significant differences in respiratory symptoms, physical examination, disease severity or inflammation markers were found between AATD patients and non AATD patients.


Asunto(s)
Asma , Deficiencia de alfa 1-Antitripsina , Asma/diagnóstico , Pruebas Genéticas , Genotipo , Humanos , alfa 1-Antitripsina/genética , Deficiencia de alfa 1-Antitripsina/complicaciones , Deficiencia de alfa 1-Antitripsina/epidemiología , Deficiencia de alfa 1-Antitripsina/genética
2.
J Endocrinol Invest ; 44(12): 2635-2643, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33860907

RESUMEN

PURPOSE: Malignancy prediction in indeterminate thyroid nodules is still challenging. We prospectively evaluated whether the combination of ultrasound (US) risk stratification and molecular testing improves the assessment of malignancy risk in Bethesda Category IV thyroid nodules. METHODS: Ninety-one consecutively diagnosed Bethesda Category IV thyroid nodules were prospectively evaluated before surgery by both ACR- and EU-TIRADS US risk-stratification systems and by a further US-guided fine-needle aspiration cytology (FNAC) for the following molecular testing: BRAFV600E, N-RAS codons 12/13, N-RAS codon 61, H-RAS codons 12/13, H-RAS codon 61, K-RAS codons 12/13, and K-RAS codon 61 point-mutations, as well as PAX8/PPARγ, RET/PC1, and RET/PTC 3 rearrangements. RESULTS: At histology, 37% of nodules were malignant. No significant association was found between malignancy and either EU- or ACR-TIRADS. In total, 58 somatic mutations were identified, including 3 BRAFV600E (5%), 5 N-RAS 12/13 (9%), 13 N-RAS 61 (22%), 7 H-RAS 12/13 (12%), 11 H-RAS 61 (19%), 6 K-RAS 12/13 (10%), 8 K-RAS 61 (14%) mutations and 2 RET/PTC1 (4%), 0 RET/PTC 3 (0%), 3 PAX8/PPARγ (5%) rearrangements. At least one somatic mutation was found in 28% and 44% of benign and malignant nodules, respectively, although malignancy was not statistically associated with the outcome of the mutational test. However, the combination of ACR-, but not EU-, TIRADS with the presence of at least one somatic mutation, was significantly associated with malignant histology (P = 0.03). CONCLUSION: US risk stratification and FNAC molecular testing may synergistically contribute to improve malignancy risk estimate of Bethesda category IV thyroid nodules.


Asunto(s)
Biopsia con Aguja Fina/métodos , Técnicas de Diagnóstico Molecular/métodos , Medición de Riesgo/métodos , Glándula Tiroides , Neoplasias de la Tiroides , Nódulo Tiroideo/diagnóstico , Ultrasonografía/métodos , Femenino , Genes ras/genética , Humanos , Biopsia Guiada por Imagen/métodos , Italia/epidemiología , Masculino , Persona de Mediana Edad , Mutación , Pronóstico , Proteínas Proto-Oncogénicas B-raf/genética , Glándula Tiroides/diagnóstico por imagen , Glándula Tiroides/metabolismo , Glándula Tiroides/patología , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/patología , Nódulo Tiroideo/epidemiología , Factores de Transcripción/genética
3.
Reumatismo ; 71(2): 85-87, 2019 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-31309779

RESUMEN

Familial mediterranean fever (FMF) is an inherited autoinflammatory disorder characterized by recurrent episodes of fever and painful inflammation involving the intra-abdominal organs, the lungs and the joints, which is highly prevalent in specific ethnic groups including the Iranians. We report a 12-year-old boy from Iran, with a clinical history of recurrent fever. Based on the suggestive clinical data, mutational analysis revealed the presence of the novel c.1945C>T heterozygous variant in exon 10, which leads to a leucine to phenylalanine change at position 649 of the protein. The mutation was inherited from the mother. This novel mutation lies in exon 10 of the MEFV gene, which encodes for a domain called B30.2-SPRY, located in the C-terminal region of the pyrin protein and contains the most frequent mutations associated with FMF. The present report expands the spectrum of MEFV gene mutations associated with FMF. The uniqueness of this study, compared with other published case reports, consists in the new mutation found in the MEFV gene. In fact, new mutations in this gene are of high interest, in order to better understand the role of this gene in autoinflammation.


Asunto(s)
Fiebre Mediterránea Familiar/genética , Mutación , Pirina/genética , Niño , Humanos , Irán , Masculino
4.
Int J Immunogenet ; 45(1): 22-25, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29227030

RESUMEN

The FCGR locus is characterized by high polymorphism and sequence homology. In particular, the Ile232Thr polymorphism in the FCGR2B gene results in inaccurate genotyping in most published papers. The purpose of the study was to develop an accurate genotyping assay able to discriminate this polymorphism.


Asunto(s)
Técnicas de Genotipaje/métodos , Polimorfismo Genético , Receptores de IgG/genética , Femenino , Humanos , Masculino
5.
Clin Genet ; 87(6): 507-16, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25345868

RESUMEN

Founder mutations in specific populations are common in several Mendelian disorders. They are shared by apparently unrelated families that inherited them from a common ancestor that existed hundreds to thousands of years ago. They have been proven to impact in molecular diagnostics strategies in specific populations, where they can be assessed as the first screening step and, if positive, avoid further expensive gene scanning. In Lynch syndrome (LS), a dominantly inherited colorectal cancer disease, more than 50 founder pathogenic mutations have been described so far in the mismatch repair (MMR) genes (MLH1, MSH2, MSH6 and PMS2). We here provide a comprehensive summary of the founder mutations found in the MMR genes and an overview of their main characteristics. At a time when high-throughput strategies are being introduced in the molecular diagnostics of cancer, genetic testing for founder mutations can complement next generation sequencing (NGS) technologies to most efficiently identify MMR gene mutations in any given population. Additionally, special attention is paid to MMR founder mutations with interesting anthropological significance.


Asunto(s)
Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Reparación de la Incompatibilidad de ADN/genética , Efecto Fundador , Mutación , Proteínas Adaptadoras Transductoras de Señales/genética , Antígenos de Neoplasias/genética , Moléculas de Adhesión Celular/genética , Neoplasias Colorrectales Hereditarias sin Poliposis/diagnóstico , Neoplasias Colorrectales Hereditarias sin Poliposis/epidemiología , Manejo de la Enfermedad , Epigénesis Genética , Molécula de Adhesión Celular Epitelial , Genética de Población , Mutación de Línea Germinal , Humanos , Judíos/genética , Homólogo 1 de la Proteína MutL , Proteína 2 Homóloga a MutS/genética , Proteínas Nucleares/genética , Vigilancia de la Población , Pronóstico
6.
Br J Dermatol ; 173(3): 731-8, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25913354

RESUMEN

BACKGROUND: Epidermolysis bullosa (EB) is caused by mutations in genes that encode proteins belonging to the epidermal-dermal junction assembly. Due to the extreme clinical/genetic heterogeneity of the disease, the current methods available for diagnosing EB involve immunohistochemistry of biopsy samples and transmission electron microscopy followed by single-candidate gene Sanger sequencing (SS), which are labour-intensive and expensive clinical pathways. OBJECTIVES: According to the recently published recommendations for the diagnosis and treatment of EB, the assessment of the mutational landscape is now a fundamental step for developing a comprehensive diagnostic path. We aimed to develop a customized, cost-effective amplicon panel for the complete and accurate sequencing of all the pathogenic genes already identified in EB, and to minimize the processing time required for the execution of the test and to refine the analysis pipeline to achieve cost-effective results from the perspective of a routine laboratory set-up. Next-generation sequencing (NGS) via the parallel ultra-deep sequencing of many genes represents a proper method for reducing the processing time and costs of EB diagnostics. MATERIALS AND METHODS: We developed an EB disease-comprehensive AmpliSeq panel to accomplish the NGS on an Ion Torrent Personal Genome Machine platform. The panel was performed on 10 patients with known genetic diagnoses and was then employed in eight family trios with unknown molecular footprints. RESULTS: The panel was successful in finding the causative mutations in all 10 patients with known mutations, fully confirming the SS data and providing proof of concept of the sensitivity, specificity and accuracy of this procedure. In addition to being consistent with the clinical diagnosis, it was also effective in the trios, identifying all of the variants, including ones that the SS missed or de novo mutations. CONCLUSIONS: The NGS and AmpliSeq were shown to be an effective approach for the diagnosis of EB, resulting in a cost- and time-effective 72-h procedure.


Asunto(s)
Epidermólisis Ampollosa/diagnóstico , Mutación/genética , Análisis de Secuencia de ADN/métodos , Moléculas de Adhesión Celular/genética , Colágeno Tipo VII/genética , Análisis Costo-Beneficio , ADN/genética , Epidermólisis Ampollosa/economía , Epidermólisis Ampollosa/genética , Femenino , Heterocigoto , Humanos , Queratina-5/genética , Masculino , Análisis de Secuencia de ADN/economía , Kalinina
7.
Eur J Paediatr Neurol ; 23(3): 410-417, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30837194

RESUMEN

AIM: The COL4A1 gene (13q34) encodes the α1 chain of type IV collagen, a crucial component of the basal membrane. COL4A1 mutations have been identified as a cause of a multisystem disease. Brain MRI in COL4A1-mutated patients typically shows vascular abnormalities and white matter lesions. Cortical malformations (specifically schizencephaly) have also recently been described in these patients, suggesting that these, too, could be part of the phenotypic spectrum of COL4A1 mutations. The aim of our work was to retrospectively evaluate COL4A1-mutated subjects diagnosed at our centers in order to assess the frequency and define the type of cortical malformations encountered in these individuals. METHOD: We retrospectively reviewed MRI data of 18 carriers of COL4A1 mutations diagnosed in our centers between 2010 and 2016. RESULTS: We identified polymicrogyria in two patients, and schizencephaly in the mother of a further patient. INTERPRETATION: Our findings confirm that cortical malformations should be considered to fall within the phenotypic spectrum of COL4A1 mutations and show that not only schizencephaly but also polymicrogyria can also be found in mutated individuals. Although further studies are needed to clarify the underlying pathogenetic mechanism, independently of this, the timing of the brain damage could be the crucial factor determining the type of lesion.


Asunto(s)
Colágeno Tipo IV/genética , Malformaciones del Desarrollo Cortical/genética , Malformaciones del Desarrollo Cortical/patología , Adulto , Niño , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Mutación , Estudios Retrospectivos
9.
Acta Otorhinolaryngol Ital ; 37(4): 308-311, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28872160

RESUMEN

Dominant GJB2 mutations are known to cause a syndromic form of sensorineural hearing loss associated with palmo-plantar skin manifestations. We present the genotype/phenotype correlations of a new GJB2 mutation identified in three generations of an Italian family (proband, mother and grandfather) whose members are affected by sensorineural hearing impairment associated with adult-onset palmoplantar keratoderma. In all affected members we identified a new heterozygous GJB2 mutation (c.66G > T, p.Lys22Asn) whose segregation, population frequency and in silico prediction analysis have suggested a pathogenic role. The p.Lys22Asn GJB2 mutation causes a dominant form of hearing loss associated with variable expression of palmoplantar keratoderma, representing a model of full penetrance, with an age-dependent effect on the phenotype.


Asunto(s)
Conexinas/genética , Pérdida Auditiva Sensorineural/genética , Queratodermia Palmoplantar/genética , Mutación , Anciano , Niño , Conexina 26 , Femenino , Humanos , Masculino , Persona de Mediana Edad , Linaje , Fenotipo , Adulto Joven
10.
Cancer Res ; 61(21): 7798-802, 2001 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-11691795

RESUMEN

Hereditary nonpolyposis colorectal cancer (HNPCC) is attributable to a deficiency of mismatch repair. Inactivation of DNA mismatch repair underlies the genesis of microsatellite instability in colorectal cancer. Germline mutations in three DNA mismatch repair genes, hMSH2, hMLH1, and hMSH6, have been found to segregate in HNPCC and HNPCC-like families. The two DNA mismatch repair genes hPMS1 and hPMS2 have also been suggested to predispose to HNPCC. In this study, 84 HNPCC and HNPCC-like kindreds without known mutations in the other three known DNA mismatch repair genes were screened for germline mutations in the hPMS1 or hPMS2 gene. No clear-cut pathogenic mutations were identified. Conversion technology was used to detect a large hMSH2 deletion in two affected members of the kindred in which the hPMS1 mutation was originally reported, whereas the hPMS1 mutation was only present in one of these two individuals. Since the hPMS1 and hPMS2 genes were first reported, germline mutations in hPMS2 have been demonstrated primarily in patients with Turcot's syndrome. However, no mutation in any of the two genes has been found to segregate in HNPCC families. Until there is better evidence for an increased colorectal cancer risk associated with germline mutations in these genes, a conservative interpretation of the role of mutations in these genes is advised.


Asunto(s)
Adenosina Trifosfatasas/genética , Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Neoplasias Colorrectales/genética , Enzimas Reparadoras del ADN , Proteínas de Unión al ADN/genética , Proteínas de Neoplasias/genética , Adulto , Femenino , Predisposición Genética a la Enfermedad , Mutación de Línea Germinal , Humanos , Masculino , Persona de Mediana Edad , Endonucleasa PMS2 de Reparación del Emparejamiento Incorrecto , Proteínas MutL , Linaje , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
11.
Cancer Res ; 61(3): 896-9, 2001 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-11221877

RESUMEN

Aberrant crypt foci (ACF) are microscopic clusters of altered colonic crypts considered premalignant lesions in the large bowel. Genomic instability at short tandem repeats in the DNA, referred to as microsatellite instability (MSI) is the hallmark of hereditary nonpolyposis colorectal carcinoma (HNPCC) caused by mutations in DNA mismatch-repair genes, mostly hMLH1 and hMSH2. In this study, we evaluated for MSI ACF (n = 16), adenomas (n = 18), carcinomas (n =22), and lymph node metastases (n = 3) from 17 patients with colorectal cancer positive for MSI. Ten patients were members of HNPCC families; 7 patients had no family history of cancer. MSI was found in 7 of 7 (100%) ACF and 11 of 12 (91%) adenomas from patients with HNPCC. MSI was not related to histology and size of ACF. A progressive increase in instability as estimated by the number of shifted bands was observed along the ACF-adenoma-carcinoma sequence. In contrast, two of nine (22%) ACF and none of six adenomas from patients with MSI sporadic carcinoma were unstable at microsatellite loci. hMLH1 or hMSH2 protein expression was altered only in MSI-positive premalignant lesions (ACF and/or adenomas), but not in all MSI-positive lesions in patients with HNPCC. These observations provide evidence of the premalignant nature of ACF in HNPCC and suggest that MSI is a very early event both in HNPCC and in sporadic colorectal carcinogenesis, although in the latter it seems infrequent.


Asunto(s)
Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Neoplasias Colorrectales Hereditarias sin Poliposis/metabolismo , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Proteínas de Unión al ADN , Proteínas de Neoplasias/biosíntesis , Proteínas Proto-Oncogénicas/biosíntesis , Proteínas Adaptadoras Transductoras de Señales , Adenoma/genética , Adenoma/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Disparidad de Par Base , Proteínas Portadoras , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Repeticiones de Microsatélite/genética , Persona de Mediana Edad , Homólogo 1 de la Proteína MutL , Proteína 2 Homóloga a MutS , Proteínas de Neoplasias/genética , Proteínas Nucleares , Lesiones Precancerosas/genética , Lesiones Precancerosas/metabolismo , Proteínas Proto-Oncogénicas/genética
12.
Oncogene ; 17(2): 157-63, 1998 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-9674699

RESUMEN

Microsatellite instability occurs in 15% of colorectal carcinomas and may be due to replication errors (RER). The pattern of instability--'severe' vs 'mild'--and the tumorigenic pathway, as reflected by the involvement of functionally important genes, may vary according to the underlying gene(s). We defined 'mild' RER as mono- or tetranucleotide repeat instability in the absence of widespread instability at dinucleotide repeats and studied 15 colorectal tumors with this phenotype for mutations in the DNA mismatch repair genes MSH2, MLH1, MSH3, and MSH6. No mutations were found, suggesting that these genes were not implicated. We then compared colorectal cancers with 'mild' RER (n = 15), and those with 'severe' RER without (n = 11) or with (n = 22) detectable mutations in MSH2 or MLH1 to assess the involvement of mononucleotide repeats contained in the coding regions of MSH3, MSH6, BAX, and TGFbeta RII. The combined mutation rates of the above mentioned loci varied significantly between the three groups of tumors, being 0%, 25% and 52%, respectively. Furthermore, the individual genes showed specific patterns of involvement; for example, among tumors with 'severe' RER, TGFbeta RII displayed uniformly high mutation rates while MSH3, MSH6, and BAX were more frequently altered in tumors that also showed MSH2 or MLH1 mutations. Our findings suggest that different subcategories exist among unstable tumors, defined by the RER pattern on the one hand and tumorigenic pathway on the other, and structural changes of MSH2 and MLH1 are likely to explain only a proportion of these cases.


Asunto(s)
Neoplasias Colorrectales/genética , Reparación del ADN , ADN de Neoplasias/metabolismo , Repeticiones de Microsatélite , Proteínas Asociadas a Resistencia a Múltiples Medicamentos , Mutagénesis/genética , Proteínas Proto-Oncogénicas c-bcl-2 , Proteínas Adaptadoras Transductoras de Señales , Proteínas Portadoras , Neoplasias Colorrectales/clasificación , Replicación del ADN/genética , Proteínas de Unión al ADN/genética , Humanos , Homólogo 1 de la Proteína MutL , Proteína 2 Homóloga a MutS , Proteína 3 Homóloga de MutS , Proteínas de Neoplasias/genética , Proteínas Nucleares , Proteínas Proto-Oncogénicas/genética , Factor de Crecimiento Transformador beta/genética , Proteína X Asociada a bcl-2
13.
J Clin Oncol ; 19(19): 3944-50, 2001 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-11579115

RESUMEN

PURPOSE: Germline mutations in mismatch repair genes predispose to hereditary nonpolyposis colorectal cancer (HNPCC). To address effective screening programs, the true incidence of the disease must be known. Previous clinical investigations reported estimates ranging between 0.5% and 13% of all the colorectal cancer (CRC) cases, whereas biomolecular studies in Finland found an incidence of 2% to 2.7% of mutation carriers for the disease. The aim of the present report is to establish the frequency of the disease in a high-incidence area for colon cancer. PATIENTS AND METHODS: Through the data of the local CRC registry, we prospectively collected all cases of CRC from January 1, 1996, through December 31, 1997 (N = 391). Three hundred thirty-six CRC cases (85.9% of the incident cases) were screened for microsatellite instability (MSI) with six to 12 mono- and dinucleotide markers. MSI cases were subjected to MSH2 and MLH1 germline mutation analysis and immunohistochemistry; the methylation of the promoter region was studied for MLH1. RESULTS: Twenty-eight cases (8.3% of the total) showed MSI. MSI cases differed significantly from microsatellite-stable (MSS) cases for their proximal location (P <.01), high mucinous component (P <.01), and poor differentiation (P =.002). Of MSI cases studied (n = 12), only one with a family history compatible with HNPCC had a germline mutation (in MSH2). Five other patients with a family history of HNPCC (two with MSI and three with MSS tumors) did not show germline mutations. CONCLUSION: We conclude that the incidence of molecularly confirmed HNPCC (one [0.3%] of 336) in a high-incidence area for CRC is lower than in previous biomolecular and clinical estimates.


Asunto(s)
Neoplasias Colorrectales Hereditarias sin Poliposis/epidemiología , Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Proteínas de Unión al ADN , Proteínas Adaptadoras Transductoras de Señales , Adulto , Anciano , Anciano de 80 o más Años , Proteínas Portadoras , Neoplasias Colorrectales Hereditarias sin Poliposis/metabolismo , Análisis Mutacional de ADN , Femenino , Predisposición Genética a la Enfermedad , Pruebas Genéticas , Mutación de Línea Germinal , Humanos , Inmunohistoquímica , Incidencia , Masculino , Repeticiones de Microsatélite/genética , Persona de Mediana Edad , Homólogo 1 de la Proteína MutL , Proteína 2 Homóloga a MutS , Proteínas de Neoplasias/biosíntesis , Proteínas de Neoplasias/genética , Proteínas Nucleares , Estudios Prospectivos , Proteínas Proto-Oncogénicas/biosíntesis , Proteínas Proto-Oncogénicas/genética , Sistema de Registros
14.
J Med Genet ; 37(9): 646-52, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10978353

RESUMEN

INTRODUCTION: An intronic germline mutation in the MSH2 gene, A-->T at nt942+3, interferes with the exon 5 donor splicing mechanism leading to a mRNA lacking exon 5. This mutation causes typical hereditary non-polyposis colorectal cancer (HNPCC) and has been observed in numerous probands and families world wide. Recurrent mutations either arise repeatedly de novo or emanate from ancestral founding mutational events. The A-->T mutation had previously been shown to be enriched in the population of Newfoundland where most families shared a founder mutation. In contrast, in England, haplotypes failed to suggest a founder effect. If the absence of a founder effect could be proven world wide, the frequent de novo occurrence of the mutation would constitute an unexplored predisposition. METHODS: We studied 10 families from England, Italy, Hong Kong, and Japan with a battery of intragenic and flanking polymorphic single nucleotide and microsatellite markers. RESULTS: Haplotype sharing was not apparent, even within the European and Asian kindreds. Our marker panel was sufficient to detect a major mutation arising within the past several thousand generations. DISCUSSION: As a more ancient founder is implausible, we conclude that the A-->T mutation at nt942+3 of MSH2 occurs de novo with a relatively high frequency. We hypothesise that it arises as a consequence of misalignment at replication or recombination caused by a repeat of 26 adenines, of which the mutated A is the first. It is by far the most common recurrent de novo germline mutation yet to be detected in a human mismatch repair gene, accounting for 11% of all known pathogenic MSH2 mutations.


Asunto(s)
Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Proteínas de Unión al ADN , Mutación de Línea Germinal , Proteínas Proto-Oncogénicas/genética , ADN/química , ADN/genética , Salud de la Familia , Femenino , Pruebas Genéticas , Genotipo , Haplotipos , Humanos , Masculino , Repeticiones de Microsatélite , Proteína 2 Homóloga a MutS , Polimorfismo de Nucleótido Simple , Análisis de Secuencia de ADN
15.
Cancer Epidemiol Biomarkers Prev ; 7(7): 639-41, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9681535

RESUMEN

In hereditary nonpolyposis colorectal cancer (HNPCC, or Lynch syndrome) a close surveillance is usually proposed to high-risk family members with the ultimate goal of reducing cancer incidence and mortality. Through a specialized registry, between 1984 and 1996, we identified 31 families with clinical features of HNPCC. A total of 390 first-degree relatives of affected patients were considered at high risk for colorectal cancer. The main purposes of this study were: (a) to assess overall compliance; and (b) to evaluate the frequency and morphological features of tumors detected at endoscopy. Two hundred twenty-three subjects could be directly interviewed and colonoscopy strongly recommended. Each of the 86 individuals who underwent colonoscopy was matched to a control of the same age (+/-3 years) and sex (control subjects were seeking endoscopy for constipation, rectal bleeding or abdominal discomfort). Of the 390 individuals traced as "at risk," 223 (57.2%) could be contacted, and, of these, 86 (38.6%, or 22.0% of the total) underwent colonoscopy. One or more colorectal lesions were found in 35 of 86 (40.7%) HNPCC asymptomatic family members and in 15 (17.4%; P < 0.001) controls. In the former group, 29 adenomas were detected in 20 individuals as opposed to 11 adenomas in 9 subjects among controls (P < 0.03). Moreover, adenomas in family members were significantly larger [9.1 +/- 5.9 mm (mean +/- SD) versus 5.8 +/- 3.7 mm; P < 0.02] and more frequently showed a tubulovillous histological type and a high degree of dysplasia. Five colorectal carcinomas (in four patients) were detected among cases (four of which were located between the cecum and the hepatic flexure); only one was detected among controls. Surveillance of high-risk subjects in HNPCC families can be carried out only in a fraction of them, because the majority cannot be reached or refuse to collaborate. On the other hand, the frequency of newly detected lesions among family members and the possible aggressive behavior of the lesions render pancolonoscopy necessary at regular intervals of time.


Asunto(s)
Adenoma/epidemiología , Carcinoma/epidemiología , Neoplasias Colorrectales Hereditarias sin Poliposis/epidemiología , Adenoma/genética , Adenoma/patología , Adulto , Anciano , Carcinoma/genética , Carcinoma/patología , Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Neoplasias Colorrectales Hereditarias sin Poliposis/patología , Femenino , Humanos , Italia/epidemiología , Masculino , Persona de Mediana Edad , Sistema de Registros/estadística & datos numéricos
16.
Eur J Cancer ; 32A(11): 1957-62, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8943681

RESUMEN

The main aim of this study was, through the data of a population-based Registry, to establish the incidence of Dukes' A lesions by year of registration and the main clinical features, and to assess cancer-specific survival. One hundred and eighteen Dukes' A colorectal tumours were diagnosed (in 117 patients) out of 1337 registered between 1984 and 1992 in the Health Care District of Modena, Northern Italy; 94 patients were treated with surgery and 23 with endoscopic polypectomy. The frequency of Dukes' A tumours ranged between 4.8% and 18% by year of registration. Dukes' A carcinomas were significantly more frequent in the distal colon. Only 5 patients (4%) died of their cancer, and in all patients the tumour was localised in the rectum. Carcinomas associated with a poor prognosis did not show any of the biological variables usually associated with an unfavourable outcome, but, our data suggest the possibility of incomplete removal of tumours at surgery.


Asunto(s)
Neoplasias del Colon/epidemiología , Neoplasias del Recto/epidemiología , Anciano , Neoplasias del Colon/patología , Neoplasias del Colon/cirugía , Endoscopía , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Italia/epidemiología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Estudios Prospectivos , Neoplasias del Recto/patología , Neoplasias del Recto/cirugía , Tasa de Supervivencia
17.
Fam Cancer ; 1(2): 93-9, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-14574004

RESUMEN

Mutations of the mismatch repair (MMR) genes MLH1 and MSH2 are associated with hereditary nonpolyposis colorectal cancer (HNPCC), a highly penetrant autosomal dominant condition characterized by hypermutability of short tandemly repeated sequences in tumor DNA. Mutations of another MMR gene, MSH6, seem to be less common than MLH1 and MSH2 defects, and have been mostly observed in atypical HNPCC families, characterized by a weaker tumor family history, higher age at disease onset, and low degrees of microsatellite instability (MSI), predominantly involving mononucleotide runs. We have investigated the MSH6 gene sequence in the peripheral blood of 4 HNPCC and 20 atypical HNPCC probands. Two frameshift mutations within exon 4 were detected in 2 patients. One mutation was found in a proband from a typical HNPCC family, who had developed a colorectal cancer (CRC), a gastric cancer and a rectal adenoma. The CRC and the adenoma showed mild MSI limited to mononucleotide tracts, while the gastric carcinoma was microsatellite stable. The other mutation was detected in an atypical HNPCC proband, whose CRC showed widespread MSI involving both mono- and dinucleotide repeats. The phenotypic variability associated with MSH6 constitutional mutations represents a complicating factor for the optimization of strategies aimed at identifying candidates to MSH6 genetic testing.


Asunto(s)
Disparidad de Par Base , Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Neoplasias Colorrectales Hereditarias sin Poliposis/patología , Reparación del ADN , Proteínas de Unión al ADN/genética , Mutación del Sistema de Lectura , Pruebas Genéticas , Adulto , Secuencia de Bases , Análisis Mutacional de ADN , ADN de Neoplasias/análisis , Femenino , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Fenotipo , Reacción en Cadena de la Polimerasa , Neoplasias del Recto/genética , Neoplasias Gástricas/genética , Secuencias Repetidas en Tándem
18.
Dig Liver Dis ; 32(9): 807-21, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11215564

RESUMEN

The development of colorectal cancer has been viewed as an ordered process in which three main phases can be identified: initiation, promotion and progression. There is definite proof that stable alterations of the structure or sequence of DNA (mutations) represent the initiating event; these are followed by an uncontrolled expansion of the neoplastic clones which characterizes tumoural growth. Several classes of genes have been identified foncogenes, tumour suppressor genes and "mutator" genes) the alterations of which are important in the initiation as well as in the promotion and progression of tumours. Colorectal cancer, therefore, results from a series of genetic changes which lead to the progressive and irreversible loss of normal control of cell growth and differentiation. Available evidence is consistent with the hypothesis that there are several molecular pathways underlying the passage from normal mucosa to colorectal carcinoma, thus explaining the existence of intestinal tumours with a different biological nature, which may represent specific targets for prevention and cure. Well-defined molecular pathways have been identified for: A) sporadic colorectal cancer ("Loss of heterozygosity pathway"); B) familial adenomatous polyposis and related polyposis syndromes; C) hereditary non-polyposis colorectal cancer ("mutator genes/microsatellite instability pathway"); D) cancer developing in inflammatory bowel diseases; E) familial colorectal cancer. Thus, there is consistent and considerable evidence suggesting the existence of several biological pathways leading to the same phenotypical expression (i.e., colorectal cancer), and it is likely that additional pathways will be clarified in the future. From a practical point of view, tumours with a diverse biology might offer different and more effective preventive and curative approaches.


Asunto(s)
Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Predisposición Genética a la Enfermedad , Lesiones Precancerosas/patología , Femenino , Humanos , Masculino , Biología Molecular , Medición de Riesgo , Sensibilidad y Especificidad
19.
Dig Liver Dis ; 32(4): 312-7, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-11515629

RESUMEN

BACKGROUND AND AIMS: It is still unclear whether recent advancements in colorectal cancer research have led to an improvement in management and prognosis of the disease. Through the data of a specialized colorectal cancer Registry we aimed at analysing pathological staging and 5-year survival of all patients with malignancies of large bowel diagnosed between 1984 and 1997. Main objective was to ascertain whether or not we are making progress in the control of this common neoplasm. PATIENTS AND METHODS: During the 14-year period 1984-97, a total of 2,240 colorectal cancer patients were registered, for a crude incidence rate of 64.5 and 55.2/100,000/year in males and females, respectively Tumours were staged with "Tumour, Node, Metastasis" system, corresponding to Dukes' classification, into four main groups. Survival was assessed with Life Table analysis, and statistical significance--between various subgroups--evaluated with Log-Rank Test. RESULTS: Crude incidence rates of colorectal neoplasms showed minor fluctuations during initial period of registration, increasing sharply after 1990 mainly due to localized (stage I and II) lesions and, to a lesser degree, to stage III tumours. Number of advanced (stage IV and unstaged) malignancies remained virtually stable. When results were expressed as percent of total cases, the fraction of localized lesions increased from 39% in the biennium 1984-5 to 51.6% in 1986-97, and the proportion of advanced tumours fell from 39% to 21.6% (p for trend <0.001). As expected, 5-year survival was significantly (p<0.002) more favourable for individuals diagnosed in 1990-91 than for patients registered in 1984-89. CONCLUSIONS: In Northern Italy, incidence rates of colorectal carcinoma are rising. This trend is associated with a sharp increase of newly detected localized lesions and with a significant improvement of overall 5-year survival. The result may be attributed to several concomitant factors, such as: A] wider use of colonoscopy, B) increased education of patients, C) more attention given to symptoms.


Asunto(s)
Neoplasias Colorrectales/epidemiología , Tablas de Vida , Estadificación de Neoplasias , Sistema de Registros , Adulto , Anciano , Colonoscopía , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/patología , Diagnóstico Diferencial , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Análisis de Supervivencia
20.
Ann Ist Super Sanita ; 32(4): 629-42, 1996.
Artículo en Italiano | MEDLINE | ID: mdl-9382432

RESUMEN

Gastrointestinal tumours are an excellent model for the investigation of hereditary factors in cancer. Epidemiological studies on high risk population (China, Iran) evidenced a strong familiarity for esophageal cancer with up to 60% of the affected patients reporting a positive familiary history. About 10-15% of gastric cancer patients show a positive familiary history for this neoplasm. The proportion is even higher for the "diffuse" hystological type. Gastric cancer belongs to the neoplastic spectrum of hereditary nonpolyposis colorectal cancer, a genetic disease with an autosomal dominant pattern of inheritance. Familial polyposis coli and hereditary nonpolyposis colorectal cancer are the two main hereditary colon cancer syndromes. Familiar aggregation have been observed in about 10% of colorectal cancer cases. As for pancreatic cancer, anedoctal reports and one case control study have shown an increased risk of pancreatic carcinoma in patients with a positive family history both for all cancers (relative risk, RR, 2), and specific for pancreatic cancer (RR: 5).


Asunto(s)
Neoplasias del Sistema Digestivo/genética , Biomarcadores de Tumor , Cocarcinogénesis , Pólipos del Colon/genética , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/genética , Neoplasias del Sistema Digestivo/epidemiología , Genes APC , Salud Global , Infecciones por Helicobacter/complicaciones , Helicobacter pylori , Humanos , Incidencia , Italia/epidemiología , Síndromes Neoplásicos Hereditarios/epidemiología , Neoplasias Pancreáticas/genética , Riesgo , Neoplasias Gástricas/epidemiología , Neoplasias Gástricas/etiología
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