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1.
Skin Res Technol ; 21(2): 144-8, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25073884

RESUMEN

BACKGROUND: The pH at the surface of healthy human skin is around 5. Cleansing the skin with soap increases the pH of the skin, which then returns to a more acidic pH within a few hours. However, the effects of skin cleansing with soap over a long time on the pH regulatory system is still unclear. OBJECT: We compared the pH of the skin between users of a soap-based cleanser and of a mild-acidic cleanser prior to and following the cleansing. METHOD: This study had two groups of subjects, one group who had used a soap-based cleanser for more than 5 years and the other group who had used a mild-acidic cleanser for more than 5 years. The pH on the inner forearm of each subject was measured prior to and for 6 h after cleansing with a soap bar. RESULT: There were no differences between the pH of the skin these two groups prior to cleansing, immediately after cleansing or in the pH recovery rate for 6 h. CONCLUSION: These results suggest that long-term continuous use of a soap-based cleanser does not affect the pH-maintaining mechanism of human skin.


Asunto(s)
Detergentes/química , Cuidados de la Piel/métodos , Piel/química , Piel/efectos de los fármacos , Jabones/química , Jabones/farmacología , Adulto , Femenino , Humanos , Concentración de Iones de Hidrógeno , Estudios Longitudinales , Masculino , Adulto Joven
2.
Skin Res Technol ; 21(2): 247-53, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25115352

RESUMEN

BACKGROUND/PURPOSE: Washing the face with a mild cleanser is generally recommended for acne care. Occasionally, the general public has the misconception that acne is exacerbated by cleansers and furthermore it has concerns about inducing skin irritation and xerosis by intensive washing. Recently, we developed a new cleanser based on sodium laureth carboxylate and alkyl carboxylates (AEC/soap) that cleans sebum well without penetrating the stratum corneum. METHODS: We designed a controlled clinical trial conducted on adult Japanese males with moderate or less acne. Twenty subjects washed their faces with AEC/soap base cleanser twice a day for 4 weeks. Assessment of the efficacy was conducted prior to the start of the study, and at the end of weeks 2 and 4. RESULTS: Significant improvement of the acne was observed within 2 weeks, and acne lesions were not detectable in 25% of the subjects at week 4. Sebum secretion levels on the skin significantly increased on the forehead, but significantly decreased on the cheek which correlated with the improvement. No complaints of dryness or irritation occurred during the study. CONCLUSION: Washing the face twice a day with facial cleanser based on AEC/soap is an effective care for moderate or less grade facial acne.


Asunto(s)
Acné Vulgar/tratamiento farmacológico , Ácidos Carboxílicos/administración & dosificación , Detergentes/administración & dosificación , Dermatosis Facial/tratamiento farmacológico , Jabones/administración & dosificación , Acné Vulgar/patología , Administración Tópica , Adulto , Ácidos Carboxílicos/química , Fármacos Dermatológicos/administración & dosificación , Detergentes/química , Composición de Medicamentos/métodos , Dermatosis Facial/patología , Humanos , Japón , Masculino , Cuidados de la Piel/métodos , Resultado del Tratamiento , Adulto Joven
3.
Int J Cosmet Sci ; 36(4): 305-11, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24617572

RESUMEN

OBJECTIVE: Sodium laureth sulphate (SLES) is an anionic detergent, which has been used globally for personal care products because of its mildness and good foaming ability. However, SLES is somewhat invasive and stimulatory to the skin, and many consumers with sensitive skin desire milder detergents for daily use skin cleansers. We enhanced the mildness of SLES by formulating it with sodium laureth carboxylate (AEC) and lauryl glucoside (LG). METHODS: In skin soak tests, 5% detergent solutions were applied to the forearms of 10 Japanese healthy volunteers for 30 min followed by washing with tap water once a day for 4 days. Twenty-four hours after the last treatment, cutaneous capacitance measurements and visual analyses were performed. In a controlled usage study, 16 Japanese healthy volunteers used the test body cleanser for 4 weeks. Assessment of efficacy and mildness was conducted prior to the start of the study and at the end of week 4 by cutaneous conductance, dermoscopic evaluation of the stratum corneum and visual assessment by a dermatologist. RESULTS: In soak tests, cutaneous capacitance was significantly decreased on the soap-treated region and on the SLES-treated region. No significant decrease was identified on the SLES/AEC/LG-treated region with less induction of erythema or dryness. In the controlled usage study, no significant changes in cutaneous conductance or texture or damage of corneocytes on the forearm and lower thigh were found. However, visual assessment revealed a significant decrease in scaling and erythema on the lower thigh after 4 weeks of usage with an improvement of the discomfort of the consumer. The favourability rating of this formulated detergent in several questionnaire items was very good. CONCLUSION: The newly formulated skin cleanser with the combination of anionic surfactants SLES and AEC and the non-ionic surfactant LG provides a mild surfactant with a satisfactory cleansing activity for body washing.


Asunto(s)
Ácidos Carboxílicos/farmacología , Glucósidos/farmacología , Piel/efectos de los fármacos , Jabones/farmacología , Dodecil Sulfato de Sodio/análogos & derivados , Ácidos Carboxílicos/administración & dosificación , Eritema/etiología , Respuesta Galvánica de la Piel/fisiología , Glucósidos/administración & dosificación , Humanos , Japón , Masculino , Dodecil Sulfato de Sodio/administración & dosificación , Dodecil Sulfato de Sodio/farmacología , Estadísticas no Paramétricas , Encuestas y Cuestionarios , Pérdida Insensible de Agua/fisiología
4.
Ann Oncol ; 17(5): 842-7, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16524972

RESUMEN

BACKGROUND: Loss of TP53 function through gene mutation is a critical event in the development and progression of many tumour types including colorectal cancer (CRC). In vitro studies have found considerable heterogeneity amongst different TP53 mutants in terms of their transactivating abilities. The aim of this work was to evaluate whether TP53 mutations classified as functionally inactive (< or=20% of wildtype transactivation ability) had different prognostic and predictive values in CRC compared with mutations that retained significant activity. MATERIALS AND METHODS: TP53 mutations within a large, international database of CRC (n = 3583) were classified according to functional status for transactivation. RESULTS: Inactive TP53 mutations were found in 29% of all CRCs and were more frequent in rectal (32%) than proximal colon (22%) tumours (P < 0.001). Higher frequencies of inactive TP53 mutations were also seen in advanced stage tumours (P = 0.0003) and in tumours with the poor prognostic features of vascular (P = 0.006) and lymphatic invasion (P = 0.002). Inactive TP53 mutations were associated with significantly worse outcome only in patients with Dukes' stage D tumours (RR = 1.71, 95%CI 1.25-2.33, P < 0.001). Patients with Dukes' C stage tumours appeared to gain a survival benefit from 5-fluorouracil-based chemotherapy regardless of TP53 functional status for transactivation ability. CONCLUSIONS: Mutations that inactivate the transactivational ability of TP53 are more frequent in advanced CRC and are associated with worse prognosis in this stage of disease.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Colorrectales/genética , Mutación , Proteína p53 Supresora de Tumor/genética , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/genética , Adenocarcinoma/patología , Anciano , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/patología , Análisis Mutacional de ADN , Exones , Femenino , Estudios de Seguimiento , Humanos , Agencias Internacionales , Masculino , Persona de Mediana Edad , Invasividad Neoplásica/genética , Invasividad Neoplásica/patología , Estadificación de Neoplasias , Tasa de Supervivencia
5.
Gut ; 55(7): 984-90, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16407375

RESUMEN

BACKGROUND AND AIMS: Germline mutations in the LKB1 gene are known to cause Peutz-Jeghers syndrome, which is an autosomal dominant disorder characterised by hamartomatous polyposis and mucocutaneous pigmentation. This syndrome is associated with an increased risk of malignancies in different organs but there is a lack of data on cancer range and risk in LKB1 germline mutation carriers. PATIENTS AND METHODS: The cumulative incidence of cancer in 149 Peutz-Jeghers syndrome patients with germline mutation(s) in LKB1 was estimated using Kaplan-Meier time to cancer onset analyses and compared between relevant subgroups with log rank tests. RESULTS: Thirty two cancers were found in LKB1 mutation carriers. Overall cancer risks at ages 30, 40, 50, 60, and 70 years were 6%, 18%, 31%, 41%, and 67%, respectively. There were similar overall cancer risks between male and female carriers. However, there were overall cancer risk differences for exon 6 mutation carriers versus non-exon 6 mutation carriers (log rank p=0.022 overall, 0.56 in males, 0.0000084 in females). Most (22/32) of the cancers occurred in the gastrointestinal tract, and the overall gastrointestinal cancer risks at ages 40, 50, 60, and 70 years were 12%, 24%, 34%, and 63%, respectively. In females, the risks for developing gynaecologic cancer at ages 40 and 50 years were 13% and 18%, respectively. CONCLUSIONS: Mutations in exon 6 of LKB1 are associated with a higher cancer risk than mutations within other regions of the gene. Moreover, this study provides age related cumulative risks of developing cancer in LKB1 mutation carriers that should be useful for developing a tailor made cancer surveillance protocol for Peutz-Jeghers syndrome patients.


Asunto(s)
Mutación de Línea Germinal , Neoplasias/genética , Síndrome de Peutz-Jeghers/genética , Proteínas Serina-Treonina Quinasas/genética , Quinasas de la Proteína-Quinasa Activada por el AMP , Distribución por Edad , Neoplasias de la Mama/genética , Distribución de Chi-Cuadrado , Estudios de Cohortes , Análisis Mutacional de ADN , Femenino , Neoplasias Gastrointestinales/genética , Predisposición Genética a la Enfermedad , Heterocigoto , Humanos , Masculino , Neoplasias/complicaciones , Síndrome de Peutz-Jeghers/complicaciones , Medición de Riesgo , Distribución por Sexo
6.
Gut ; 52(2): 304-6, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12524418

RESUMEN

During a search for causative genes in patients with concurrent multiple primary colon tumours, we found a novel case with a germline mutation of the p53 gene, from GCC (Ala) to GTC (Val) at codon 189. Of the six primary colon tumours that this patient had, one large advanced carcinoma exhibited a somatic p53 mutation and a somatic APC mutation, in addition to the germline p53 mutation. Two early carcinomas and three adenomas had somatic APC mutations but no somatic p53 mutation or loss of the p53 allele. K-ras-2 mutations were detected in an advanced carcinoma and an early carcinoma. The present results suggest that a patient with a certain type of germline p53 mutation is predisposed to concurrent multiple colon tumours. It is also suggested that in such a patient, a somatic APC mutation is involved in tumour formation and that an additional somatic p53 mutation contributes to tumour progression.


Asunto(s)
Neoplasias del Colon/genética , Genes p53/genética , Mutación de Línea Germinal/genética , Neoplasias Primarias Múltiples/genética , Anciano , Neoplasias del Colon/patología , Pólipos del Colon/genética , Pólipos del Colon/patología , Análisis Mutacional de ADN/métodos , Humanos , Masculino , Neoplasias Primarias Múltiples/patología
7.
Oncogene ; 20(37): 5215-8, 2001 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-11526511

RESUMEN

One of the characteristics of tumors from patients with germline mutations of DNA mismatch repair genes is instability at microsatellite regions (MSI). We analysed alterations at repeated sequences of coding regions, as well as those of 5' upstream regions, in 29 MSI-High colorectal tumors from patients with hereditary nonpolyposis colorectal cancer (HNPCC) and Turcot syndrome. We found that repeated sequences in 5' upstream regions were altered in these tumors, at considerable frequencies. The (A)10 repeat in the promoter region (position -178 to approximately -169) of the GAPDH gene was altered in 17% of the tumors. The (A)10(TA)9 in the 5' upstream region (position -318 to approximately -291) of the mitochondrial isoleucyl tRNA synthetase gene (IleRS-A), coded in nuclear DNA, was altered in 59% of the tumors, whereas (A)9 in the 5' upstream region (position -859 to approximately -851) of cytoplasmic isoleucyl tRNA synthetase gene (IleRS-B) was not altered. Alteration at repeated sequences in the coding regions were 72% at TGFbetaRII(A)10, 24% at IGFIIR(G)8, 45% at BAX(G)8, 55% at E2F4(CAG)13, 66% at caspase-5 (A)10, 31% at MBD4(A)10, 55% at hMSH3(A)8 and 34% at hMSH6(C)8. The number of altered genes increased with the advancement of carcinoma according to Dukes categories: mean numbers of altered genes within these 10 genes were 2.6 for Dukes A, 4.7 for Dukes B and 7.8 for Dukes C. The mean number for adenomas was 2.0. These results suggest that the MSI phenotype also causes alteration of 5' upstream regions which may affect apoptosis and some mitochondrial functions in HNPCC and Turcot tumors, and that accumulation of altered genes with repeated sequences is associated with the progression of HNPCC and Turcot colorectal tumors.


Asunto(s)
Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Neoplasias Colorrectales/genética , Secuencias Repetitivas de Ácidos Nucleicos , Adenoma/genética , Adolescente , Adulto , Disparidad de Par Base , Citoplasma/metabolismo , Reparación del ADN , Progresión de la Enfermedad , Humanos , Persona de Mediana Edad , Fenotipo , Síndrome
8.
Genes Chromosomes Cancer ; 30(1): 32-7, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11107173

RESUMEN

It has been reported that wild-type APC protein forms a complex with beta-Catenin and GSK3beta, inducing degradation of beta-Catenin in normal cells. Both beta-Catenin and APC gene mutations have recently been shown to activate the same signaling pathway. Frequent mutations of beta-Catenin in hereditary nonpolyposis colorectal carcinomas have also been reported. It was, however, controversial whether the mutation of the beta-Catenin gene was frequent in nonfamilial colorectal carcinomas with high-frequency microsatellite instability (MSI-H). We analyzed the mutations of the APC and beta-Catenin genes in 56 nonfamilial colorectal carcinomas stratified according to the presence or absence of microsatellite instability (MSI). APC mutations were identified in 11 of 22 (50%) cases of MSI-H and 14 of 34 (41%) cases of microsatellite-stable (MSS)/low-frequency microsatellite instability (MSI-L). In contrast, the frequency of beta-Catenin mutations was significantly higher in MSI-H (6/22; 27%) than in MSS/MSI-L (1/34; 3%) (P = 0.01). beta-Catenin mutations were not detected in carcinomas with APC mutation. APC mutation occurred irrespective of MSI status. beta-Catenin mutation, however, occurred frequently in MSI-H carcinomas. Our data suggest that activation of the beta-Catenin-Tcf signaling pathway, through either beta-Catenin or APC mutation, frequently contributes to MSI-H nonfamilial colorectal carcinomas (17/22; 77%).


Asunto(s)
Neoplasias Colorrectales/genética , Proteínas del Citoesqueleto/genética , Regulación Neoplásica de la Expresión Génica , Repeticiones de Microsatélite/genética , Transducción de Señal/genética , Transactivadores , Cadherinas/genética , Proteínas de Unión al ADN/genética , Genes APC/genética , Humanos , Factor de Unión 1 al Potenciador Linfoide , Mutación/genética , Reacción en Cadena de la Polimerasa , Polimorfismo Conformacional Retorcido-Simple , Factores de Transcripción/genética , beta Catenina
9.
Am J Pathol ; 157(6): 1825-7, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11106555

RESUMEN

Familial adenomatous polyposis is characterized by multiple colorectal adenomas and an increased incidence of colorectal carcinomas. Patients also develop various extracolonic tumors, of which, thyroid carcinoma is common in young females. The occurrence of multiple carcinomas in one thyroid is frequently observed, although some carcinomas are solitary. To clarify whether each carcinoma develops independently or metastatically spreads from the first one formed, we analyzed the adenomatous polyposis coli (APC) gene mutation in each carcinoma. We found that each carcinoma had a different somatic mutation of the APC gene. This is molecular confirmation for the multicentric development of thyroid carcinomas in familial adenomatous polyposis through biallelic inactivation of the APC gene.


Asunto(s)
Poliposis Adenomatosa del Colon/genética , Carcinoma/genética , Carcinoma/patología , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/patología , Adulto , Alelos , Cromosomas Humanos Par 5/genética , Femenino , Silenciador del Gen , Genes APC/genética , Humanos , Pérdida de Heterocigocidad , Mutación , Reacción en Cadena de la Polimerasa , Polimorfismo Conformacional Retorcido-Simple
10.
J Clin Pathol ; 53(11): 841-5, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11127266

RESUMEN

AIMS: Microsatellite instability (MSI) was first observed in hereditary non-polyposis colorectal carcinoma (HNPCC) and was subsequently seen in non-familial colorectal carcinoma. The relation between MSI and cancer associated genes in non-familial colorectal carcinomas has yet to be evaluated. To clarify this matter, changes in cancer associated genes were examined in non-familial colorectal carcinomas. METHODS: Alterations in the adenomatous polyposis coli (APC), p53, and Ki-ras genes were analysed in 24 MSI high (alterations in four to seven of seven loci), nine MSI low (alterations in one to three of seven loci), and 31 MSI negative non-familial carcinomas. The hMSH2 and hMLH1 genes were also analysed in 24 MSI high carcinomas. RESULTS: Both the frequencies and types of alterations in the APC and p53 genes in MSI high carcinomas were the same as those in MSI low and MSI negative carcinomas; however, they were different from those seen in HNPCC. The frequency of Ki-ras mutation was significantly lower in the MSI high cases (two of 24; 8%) than in the others (15 of 38; 39%). Somatic mutation of hMSH2 or hMLH1 was detected in six of 24 (25%) of the MSI high cases. CONCLUSIONS: These results suggest that APC and p53 alterations occur irrespective of microsatellite instability status in non-familial colorectal carcinomas, and that Ki-ras mutation is not involved in MSI high non-familial colorectal carcinoma. The pathogenesis of these carcinomas may differ from both the usual adenoma-carcinoma sequence and HNPCC carcinogenesis.


Asunto(s)
Neoplasias Colorrectales/genética , Proteínas de Unión al ADN , Repeticiones de Microsatélite/genética , Secuencia de Bases , Neoplasias Colorrectales/patología , Genes APC , Genes p53 , Genes ras , Humanos , Persona de Mediana Edad , Proteína 2 Homóloga a MutS , Mutación , Invasividad Neoplásica , Proteínas Proto-Oncogénicas/genética
11.
Cancer Res ; 60(22): 6311-3, 2000 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-11103790

RESUMEN

Peutz-Jeghers syndrome (PJS) is characterized by multiple gastrointestinal hamartomatous polyps, mucocutaneous melanin deposition, and increased risk of cancer, mainly in the gastrointestinal tract. We examined mutations of the LKB1, beta-catenin, APC, K-ras, and p53 genes in 27 gastrointestinal hamartomatous polyps from 10 patients in nine PJS families. Of these hamartomatous polyps, one intestinal polyp had an adenomatous lesion, and one gastric polyp contained adenomatous and carcinomatous lesions. Germ-line mutations of the LKB1 gene were detected in six PJS families. Somatic mutations of the LKB1 gene were found in 5 polyps, whereas loss of heterozygosity (LOH) at the LKB1 locus at 19p was seen in 14 other polyps. In adenomatous lesions microdissected from hamartomatous polyps, both beta-catenin mutation and 19p LOH were detected. Furthermore, a carcinomatous lesion in a gastric hamartomatous polyp was found to contain a mutation of the p53 gene and LOH at the p53 locus in addition to LOH at the LKB1 locus and a beta-catenin mutation. K-ras mutations were detected in a few polyps, whereas no APC mutation or 5q LOH was detected in hamartomatous polyps. These results suggest that gastrointestinal hamartomatous polyps in PJS patients develop through inactivation of the LKB1 gene by germ-line mutation plus somatic mutation or LOH of the unaffected LKB1 allele, and that additional mutations of the beta-catenin gene and p53 gene convert hamartomatous polyps into adenomatous and carcinomatous lesions.


Asunto(s)
Proteínas del Citoesqueleto/genética , Mutación , Síndrome de Peutz-Jeghers/genética , Proteínas Serina-Treonina Quinasas/genética , Transactivadores , Quinasas de la Proteína-Quinasa Activada por el AMP , Adenoma/genética , Adenoma/patología , Carcinoma/genética , Carcinoma/patología , Neoplasias Gastrointestinales/genética , Neoplasias Gastrointestinales/patología , Mutación de Línea Germinal , Hamartoma/genética , Hamartoma/patología , Humanos , Pérdida de Heterocigocidad , Síndrome de Peutz-Jeghers/complicaciones , Síndrome de Peutz-Jeghers/patología , beta Catenina
12.
Jpn J Cancer Res ; 91(11): 1100-2, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11092973

RESUMEN

Thyroid carcinoma is the first symptom in some patients with familial adenomatous polyposis (FAP). We evaluated the cellular localization of beta-catenin in thyroid carcinomas associated (n = 4) or not associated (n = 173) with FAP, since loss of functional protein of the adenomatous polyposis coli (APC) gene leads to nuclear accumulation of beta-catenin in adenomas and carcinomas of the FAP colon. Immunoreactive beta-catenin was demonstrated at the cell membrane of glandular cells of the non-neoplastic thyroid and non-FAP carcinomas. On the other hand, cytoplasmic and nuclear accumulation of beta-catenin is specific to FAP-associated papillary carcinomas. The abnormality in the APC / beta-catenin pathway is thus also important in FAP-associated thyroid carcinoma, and beta-catenin immunohistochemistry is a feasible screening method to identify occult FAP in young patients with thyroid tumors.


Asunto(s)
Poliposis Adenomatosa del Colon/metabolismo , Carcinoma Papilar/metabolismo , Proteínas del Citoesqueleto/metabolismo , Neoplasias de la Tiroides/metabolismo , Transactivadores , Poliposis Adenomatosa del Colon/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Papilar/genética , Núcleo Celular/metabolismo , Femenino , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Neoplasias de la Tiroides/genética , beta Catenina
13.
J Gastroenterol ; 35(10): 779-83, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11063223

RESUMEN

Gastrointestinal stromal tumor (GIST) in the distal third of the rectum was detected in a 57-year-old man who underwent an abdominoperineal resection of the rectum. Because the tumor expressed CD34 and c-kit gene product, but did not express smooth muscle actin or S-100 protein, it was diagnosed as an uncommitted type of GIST. Moreover, a specific mutation in the sequence coding the juxtamembrane domain in exon 11 of the c-kit proto-oncogene was revealed by a polymerase chain reaction-single-strand conformation polymorphism method. One year after resection, the patient developed multiple liver metastases. It is suggested that a specific mutation in exon 11 of the c-kit proto-oncogene may have played an essential role in the development of the liver metastases.


Asunto(s)
Exones/genética , Mutación , Proteínas Proto-Oncogénicas c-kit/genética , Proto-Oncogenes/genética , Neoplasias del Recto/genética , Humanos , Neoplasias Hepáticas/secundario , Masculino , Persona de Mediana Edad , Proto-Oncogenes Mas
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.
Nihon Rinsho ; 58(7): 1400-4, 2000 Jul.
Artículo en Japonés | MEDLINE | ID: mdl-10921312

RESUMEN

Peutz-Jeghers syndrome(PJS) is an autosomal dominant disease which is characterized by melanin spots on lips and buccal mucosa, and multiple gastrointestinal hamartomatous polyps. Patients are at risk of forming carcinomas in the gastrointestinal tract, uterus, ovary, breast and other organs. The LKB1(STK11) gene at chromosome 19p13.3 has been identified in 1998 as the causative gene for PJS, and germline mutations of this gene have been detected in about 50 PJS families. These mutations include nonsense mutations, frameshift mutations and missense mutations, all of which are assumed to inactivate the LKB1 gene. LKB1 gene appears to be a tumor suppressor gene, and inactivation of this gene through germline mutation and loss of normal allele may develop hamartomatous polyps. However, the function of LKB1 and mechanism of carcinoma formation are still unclear.


Asunto(s)
Síndrome de Peutz-Jeghers/genética , Quinasas de la Proteína-Quinasa Activada por el AMP , Cromosomas Humanos Par 19/genética , Mutación de Línea Germinal , Humanos , Síndrome de Peutz-Jeghers/patología , Proteínas Serina-Treonina Quinasas/genética
16.
Nihon Rinsho ; 58(6): 1225-30, 2000 Jun.
Artículo en Japonés | MEDLINE | ID: mdl-10879045

RESUMEN

Germline mutations in one of two alleles of c-ret, c-met and c-kit protooncogenes have been revealed to be the causes of three autosomal dominant hereditary tumors; multiple endocrine neoplasia type 2(MEN2), hereditary papillary renal cell carcinoma (HPRCC), and familial gastrointestinal stromal tumor(FGIST), respectively. Patients with MEN2A have missense mutations at extracellular cysteine rich domain of c-ret, those with MEN2B have missense mutations at tyrosine kinase domain of c-ret, those with HPRCC have missense mutations at tyrosine kinase domain of c-met, and those with FGIST have in-frame deletion mutations at juxtamembrane domain of c-kit. All of these mutations are assumed to cause constitutive activation of protooncogenes without binding to ligands, resulting in tumor formation.


Asunto(s)
Mutación de Línea Germinal , Síndromes Neoplásicos Hereditarios/genética , Proto-Oncogenes/genética , Alelos , Cisteína , Genes Dominantes/genética , Humanos , Mutación Missense , Estructura Terciaria de Proteína/genética , Proteínas Tirosina Quinasas
17.
Jpn J Clin Oncol ; 30(2): 82-8, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10768871

RESUMEN

BACKGROUND: Familial adenomatous polyposis (FAP) patients develop various extracolonic lesions; however, the relationship between germline mutation of the APC gene and extracolonic manifestations is mostly unknown. To examine the genotype-phenotype relationship, we compared the APC mutation and clinical data. METHODS: Germline mutations from codon 157 to 1465 of the APC gene were identified in 39 families of FAP and clinical data were collected from 80 patients of these families. Germline mutations were classified into two groups: mutations from exon 4 to 9 (codon 157 to 416, Group 1) and those from exon 10 to 15H (codon 564 to 1465, Group 2). The complication rates of extracolonic manifestations were compared between these two groups. RESULTS: Frequencies of duodenal polyps and gastric adenomas in Group 2 were higher than those in Group 1 (p < 0.0001 and p < 0.0004, respectively) and development of osteoma was more frequent in Group 2 (p = 0.01). The number of colorectal polyps and retinal pigments also correlated with the germline mutation, which was consistent with previous reports. However, such correlations were less obvious with regard to gastric fundic polyps, desmoid tumors, soft tissue tumors and colorectal cancer. CONCLUSION: There are two types with regard to extracolonic manifestations of FAP: one is more severely affected according to the position of germline mutation of the APC gene and the other is not affected.


Asunto(s)
Adenoma/genética , Poliposis Adenomatosa del Colon/genética , Proteínas del Citoesqueleto/genética , ADN de Neoplasias/genética , Enfermedades Duodenales/genética , Genes APC , Mutación de Línea Germinal , Neoplasias Gástricas/genética , Adenoma/etiología , Poliposis Adenomatosa del Colon/complicaciones , Poliposis Adenomatosa del Colon/patología , Adolescente , Adulto , Análisis Mutacional de ADN , Enfermedades Duodenales/etiología , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Linaje , Fenotipo , Pólipos , Neoplasias Gástricas/etiología
19.
Int J Cancer ; 85(4): 518-22, 2000 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-10699924

RESUMEN

We have previously observed that all human hepatocellular carcinomas (HCCs) from HBV carriers examined had the integrated X region. In this study, HBV DNA was isolated from an integration site in one HCC that had a single, very small integrated viral DNA including the X region, but it had no expression of X gene as poly(A)RNA. It was found that HBV DNA was present between alphoid repetitive sequences, and it included Enhancer and X regions, encompassing the adr sequence from 910 to 1811. Nucleotides for 8 amino acids at the 3' end, a stop codon of X gene and a poly(A) signal downstream of X gene were lost by integration, and nucleotides for 7 amino acids and a stop codon were substituted by a connected alphoid sequence. When this cloned HBV DNA was transfected with an expression vector to an immortalized mouse liver epithelial cell line, MLE-10, malignant transformation occurred. Transformants having expressed poly(A)RNA of the X gene showed anchorage-independent growth in soft agar and tumor formation in the subcutis of nude mice. The mRNA level of EGFR was found to be remarkably enhanced in X-transformed cells, in contrast with the absence of this mRNA in parental and ras-transformed MLE-10. Our data provide evidence that the Enhancer-X region alone is the key contributor to the malignant change of pre-malignant liver cells in HBV carriers through activation of some specific genes, such as EGFR.


Asunto(s)
Carcinoma Hepatocelular/genética , Transformación Celular Neoplásica , Elementos de Facilitación Genéticos , Receptores ErbB/genética , Virus de la Hepatitis B/genética , Hepatitis B/genética , Neoplasias Hepáticas/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/virología , Portador Sano , Línea Celular , ADN de Neoplasias/genética , ADN de Neoplasias/aislamiento & purificación , ADN Viral/genética , ADN Viral/aislamiento & purificación , Regulación Neoplásica de la Expresión Génica , Humanos , Hígado , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/virología , Ratones , Datos de Secuencia Molecular , ARN Mensajero/genética , Mapeo Restrictivo , Transcripción Genética
20.
Cancer Res ; 59(18): 4506-9, 1999 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-10493496

RESUMEN

Hereditary nonpolyposis colorectal cancer (HNPCC) is characterized by defective DNA mismatch repair, which results in genetic instability of tumors; however, only a few target genes have been recognized. Our previous study detected a low frequency of APC gene mutation (21%) in colorectal tumors from HNPCC patients, in contrast to a high frequency of APC gene alteration (>70%) in non-HNPCC tumors. Because both beta-catenin and ACP gene mutations have recently been shown to activate the same signaling pathway, we analyzed beta-catenin mutation in HNPCC tumors. A notable frequency of beta-catenin gene mutation (43%, 12 of 28) was found to occur in HNPCC colorectal tumors. Beta-catenin mutations were not detected in tumors with APC mutations. All beta-catenin mutations detected in HNPCC tumors existed within the regulatory domain of beta-catenin. Immunohistochemical staining of tumors with this mutation showed accumulation of beta-catenin protein in nuclei. These and previous data from our laboratory suggest that activation of the beta-catenin-Tcf signaling pathway, through either beta-catenin or APC mutation, contributes to HNPCC colorectal carcinogenesis in approximately 65% of cases.


Asunto(s)
Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Neoplasias Colorrectales/genética , Proteínas del Citoesqueleto/genética , Proteínas de Unión al ADN , Genes APC , Mutación , Transactivadores , Disparidad de Par Base , Cadherinas/genética , Pólipos del Colon/genética , Neoplasias Colorrectales/patología , Neoplasias Colorrectales Hereditarias sin Poliposis/patología , Mutación de Línea Germinal , Humanos , Japón , Proteína 2 Homóloga a MutS , Invasividad Neoplásica , Proteínas Proto-Oncogénicas/genética , beta Catenina
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