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1.
Rev Soc Bras Med Trop ; 49(2): 150-7, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27192582

RESUMEN

Approximately 90% of the world population is infected by Epstein-Barr virus (EBV). Usually, it infects B lymphocytes, predisposing them to malignant transformation. Infection of epithelial cells occurs rarely, and it is estimated that about to 10% of gastric cancer patients harbor EBV in their malignant cells. Given that gastric cancer is the third leading cause of cancer-related mortality worldwide, with a global annual incidence of over 950,000 cases, EBV-positive gastric cancer is the largest group of EBV-associated malignancies. Based on gene expression profile studies, gastric cancer was recently categorized into four subtypes; EBV-positive, microsatellite unstable, genomically stable and chromosomal instability. Together with previous studies, this report provided a more detailed molecular characterization of gastric cancer, demonstrating that EBV-positive gastric cancer is a distinct molecular subtype of the disease, with unique genetic and epigenetic abnormalities, reflected in a specific phenotype. The recognition of characteristic molecular alterations in gastric cancer allows the identification of molecular pathways involved in cell proliferation and survival, with the potential to identify therapeutic targets. These findings highlight the enormous heterogeneity of gastric cancer, and the complex interplay between genetic and epigenetic alterations in the disease, and provide a roadmap to implementation of genome-guided personalized therapy in gastric cancer. The present review discusses the initial studies describing EBV-positive gastric cancer as a distinct clinical entity, presents recently described genetic and epigenetic alterations, and considers potential therapeutic insights derived from the recognition of this new molecular subtype of gastric adenocarcinoma.


Asunto(s)
Adenocarcinoma/virología , Infecciones por Virus de Epstein-Barr/genética , Neoplasias Gástricas/virología , Adenocarcinoma/genética , Epigénesis Genética , Infecciones por Virus de Epstein-Barr/complicaciones , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Gástricas/genética
2.
Rev. Soc. Bras. Med. Trop ; 49(2): 150-157, Mar.-Apr. 2016. tab, graf
Artículo en Inglés | LILACS | ID: lil-782099

RESUMEN

Abstract: Approximately 90% of the world population is infected by Epstein-Barr virus (EBV). Usually, it infects B lymphocytes, predisposing them to malignant transformation. Infection of epithelial cells occurs rarely, and it is estimated that about to 10% of gastric cancer patients harbor EBV in their malignant cells. Given that gastric cancer is the third leading cause of cancer-related mortality worldwide, with a global annual incidence of over 950,000 cases, EBV-positive gastric cancer is the largest group of EBV-associated malignancies. Based on gene expression profile studies, gastric cancer was recently categorized into four subtypes; EBV-positive, microsatellite unstable, genomically stable and chromosomal instability. Together with previous studies, this report provided a more detailed molecular characterization of gastric cancer, demonstrating that EBV-positive gastric cancer is a distinct molecular subtype of the disease, with unique genetic and epigenetic abnormalities, reflected in a specific phenotype. The recognition of characteristic molecular alterations in gastric cancer allows the identification of molecular pathways involved in cell proliferation and survival, with the potential to identify therapeutic targets. These findings highlight the enormous heterogeneity of gastric cancer, and the complex interplay between genetic and epigenetic alterations in the disease, and provide a roadmap to implementation of genome-guided personalized therapy in gastric cancer. The present review discusses the initial studies describing EBV-positive gastric cancer as a distinct clinical entity, presents recently described genetic and epigenetic alterations, and considers potential therapeutic insights derived from the recognition of this new molecular subtype of gastric adenocarcinoma.


Asunto(s)
Humanos , Neoplasias Gástricas/virología , Adenocarcinoma/virología , Infecciones por Virus de Epstein-Barr/genética , Neoplasias Gástricas/genética , Adenocarcinoma/genética , Regulación Neoplásica de la Expresión Génica , Infecciones por Virus de Epstein-Barr/complicaciones , Epigénesis Genética
3.
Braz. j. infect. dis ; 18(3): 315-326, May-June/2014. tab, graf
Artículo en Inglés | LILACS, Sec. Est. Saúde SP | ID: lil-712950

RESUMEN

Kaposi's sarcoma is a multifocal vascular lesion of low-grade potential that is most often present in mucocutaneous sites and usually also affects lymph nodes and visceral organs. The condition may manifest through purplish lesions, flat or raised with an irregular shape, gastrointestinal bleeding due to lesions located in the digestive system, and dyspnea and hemoptysis associated with pulmonary lesions. In the early 1980s, the appearance of several cases of Kaposi's sarcoma in homosexual men was the first alarm about a newly identified epidemic, acquired immunodeficiency syndrome. In 1994, it was finally demonstrated that the presence of a herpes virus associated with Kaposi's sarcoma called HHV-8 or Kaposi's sarcoma herpes virus and its genetic sequence was rapidly deciphered. The prevalence of this virus is very high (about 50%) in some African populations, but stands between 2% and 8% for the entire world population. Kaposi's sarcoma only develops when the immune system is depressed, as in acquired immunodeficiency syndrome, which appears to be associated with a specific variant of the Kaposi's sarcoma herpes virus. There are no treatment guidelines for Kaposi's sarcoma established in Brazil, and thus the Brazilian Society of Clinical Oncology and the Brazilian Society of Infectious Diseases developed the treatment consensus presented here.


Asunto(s)
Femenino , Humanos , Masculino , Sarcoma de Kaposi , Brasil , Estadificación de Neoplasias , Pronóstico , Factores de Riesgo , Sarcoma de Kaposi/diagnóstico , Sarcoma de Kaposi/epidemiología , Sarcoma de Kaposi/terapia , Sociedades Médicas
4.
Braz J Infect Dis ; 18(3): 315-26, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24525061

RESUMEN

Kaposi's sarcoma is a multifocal vascular lesion of low-grade potential that is most often present in mucocutaneous sites and usually also affects lymph nodes and visceral organs. The condition may manifest through purplish lesions, flat or raised with an irregular shape, gastrointestinal bleeding due to lesions located in the digestive system, and dyspnea and hemoptysis associated with pulmonary lesions. In the early 1980s, the appearance of several cases of Kaposi's sarcoma in homosexual men was the first alarm about a newly identified epidemic, acquired immunodeficiency syndrome. In 1994, it was finally demonstrated that the presence of a herpes virus associated with Kaposi's sarcoma called HHV-8 or Kaposi's sarcoma herpes virus and its genetic sequence was rapidly deciphered. The prevalence of this virus is very high (about 50%) in some African populations, but stands between 2% and 8% for the entire world population. Kaposi's sarcoma only develops when the immune system is depressed, as in acquired immunodeficiency syndrome, which appears to be associated with a specific variant of the Kaposi's sarcoma herpes virus. There are no treatment guidelines for Kaposi's sarcoma established in Brazil, and thus the Brazilian Society of Clinical Oncology and the Brazilian Society of Infectious Diseases developed the treatment consensus presented here.


Asunto(s)
Sarcoma de Kaposi , Brasil , Femenino , Humanos , Masculino , Estadificación de Neoplasias , Pronóstico , Factores de Riesgo , Sarcoma de Kaposi/diagnóstico , Sarcoma de Kaposi/epidemiología , Sarcoma de Kaposi/terapia , Sociedades Médicas
5.
World J Gastroenterol ; 19(38): 6438-46, 2013 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-24151362

RESUMEN

AIM: To compare the performance of three commercially available anti-human epidermal growth factor receptor 2 (HER2) antibodies in whole-tissue sections and tissue microarrays (TMAs) of a series of gastric tumors. METHODS: We present a comparative analysis of three anti-HER2 antibodies (HercepTest, 4B5 and SP3) using TMA and whole-tissue sections prepared from the same paraffin blocks of 199 gastric adenocarcinomas operated upon between January 2004 and December 2008 at a Brazilian cancer hospital. The data on the patients' age, sex, the anatomical location of the tumor and the Lauren's histological classification were collected from clinical and pathological records. The immunohistochemical (IHC) results were examined by two pathologists and the cases were classified as positive (3+), equivocal (2+) and negative (0 or 1+), according to the criteria of the IHC scoring system of gastric cancer. TMAs and whole-tissue sections were evaluated separately and independently. All cases yielding discordant IHC results and/or scored as 2+ were subjected to dual-color in situ hybridization in order to determine the final HER2 status. Besides determining the sensitivity and predictive value for HER2-positive status, we measured the accuracy of each antibody by calculating the area under the receiver operating characteristic (ROC) curve. The agreement between the results obtained using the TMAs and those obtained using the whole-tissue sections was assessed by means of Kappa coefficient. RESULTS: Intratumoral heterogeneity of HER2 expression was observed with all antibodies. HER2-positive expression (3+) in the whole-tissue sections was observed in 23 cases (11.6%) using the 4B5 antibody, in 18 cases (9.1%) using the SP3 antibody and in 10 cases (5.1%) using the HercepTest antibody. In the TMAs, 11 positive cases (5.6%) were identified using SP3 antibody, 9 (4.6%) using the 4B5 antibody and 6 (3%) using the HercepTest antibody. The sensitivity using whole-tissue sections and TMA, respectively, was 95.2% and 42.9% with 4B5, 90.5% and 66.7% with SP3 and 47.6% and 42.9% with HercepTest. The accuracy, calculated from the area under the ROC curve, using whole-tissue sections and TMA, respectively, was 0.91 and 0.79 by 4B5, 0.86 and 0.80 by SP3 and 0.73 and 0.71 by HercepTest. The concordance of the results obtained using whole-tissue sections and TMA was 97.4% (Kappa 0.75) using HercepTest, 85.6% (Kappa 0.56) using SP3 and 84.1% (Kappa 0.38) using 4B5. CONCLUSION: The use of the 4B5 antibody on whole-tissue sections was the most accurate IHC method for evaluating HER2 expression in gastric adenocarcinoma.


Asunto(s)
Adenocarcinoma/enzimología , Anticuerpos , Biomarcadores de Tumor/análisis , Inmunohistoquímica , Microtomía , Receptor ErbB-2/análisis , Neoplasias Gástricas/enzimología , Análisis de Matrices Tisulares , Adenocarcinoma/genética , Adenocarcinoma/inmunología , Adenocarcinoma/patología , Adulto , Anciano , Anciano de 80 o más Años , Área Bajo la Curva , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/inmunología , Brasil , Femenino , Humanos , Hibridación in Situ , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Valor Predictivo de las Pruebas , Curva ROC , Receptor ErbB-2/genética , Receptor ErbB-2/inmunología , Reproducibilidad de los Resultados , Neoplasias Gástricas/genética , Neoplasias Gástricas/inmunología , Neoplasias Gástricas/patología
6.
Rev. méd. Minas Gerais ; 13(4 supl.2): 30-34, dez.2003. tab
Artículo en Portugués | LILACS | ID: lil-776052

RESUMEN

A anemia por deficiência de ferro é a doença nutricional mais prevalente no mundo, sobretudo na infância, constituindo-se sério problema de Saúde Pública. No Brasil, os dados disponíveis apresentam ampla variação de cunho regional, com tendência a aumento de prevalência em seus índices mais recentes. Neste estudo de revisão, seus aspectos epidemiológicos, fatores causais, grupos de risco e seus impactos sobre o indivíduo são salientados. Novas estratégias de prevenção e intervenções de caráter populacional são apresentadas como formas alternativas na sua abordagem, com resultados promissores.


lron deficiency anemia is the most prevalent nutritonal disorder of the world, speciafly on the infancy, becoming a Public Health 's serius problem. In Brazif, available works about the subject have wide regional variations, with the tendency of a prevalence's increase in these most recent representa tive datas. In this revision 's paper epidemiological aspects, cause factors, risk groups, individual consequences of iron deficiency and new pre- vention strategies was emphasized.


Asunto(s)
Humanos , Lactante , Preescolar , Niño , Anemia Ferropénica , Factores de Riesgo , Anemia Ferropénica , Deficiencias de Hierro
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