Polimorfismos IL1B-511 y TNF-A-308 en una población infectada con Helicobacter pylori de una zona de bajo riesgo de cáncer gástrico en Nariño-Colombia / IL1B-511 and TNF-A-308 polymorphisms in a population infected with Helicobacter pylori from a low-risk area of gastric cancer in Nariño-Colombia

Objetivo: Estudiar los polimorfismos IL1B-511 y TNF-A-308 asociaciados a lesiones precursoras de cáncer gástrico (CG) en una población infectada con Helicobacter pylori (H. pylori) de bajo riesgo de CG de Nariño. Material y método: De 105 pacientes con síntomas de dispepsia se incluyeron 81 infectados por H. pylori, (n=63) con gastritis no atrófica y (n=18) con lesiones precursoras de CG de Tumaco: población de bajo riesgo de CG. Las lesiones gástricas se clasificaron por el sistema de Sydney y H. pylori por tinción de Giemsa. Los polimorfismos de IL1B-511 y TNF-A-308 se genotipificaron por PCR-RFLP's. Los polimorfismos y su asociación con lesiones gastricas se evaluaron por análisis bivariado y regresión logística binomial. Resultados: Los pacientes portadores del alelo mutante T (IL-1B-511) no se encontraron a riesgo de lesiones precursoras de malignidad (OR=0,7). No se calculó el OR para TNF-A-308, por fijación del alelo normal G. Ser hombre y estar infectado por H. pylori incrementa 4,3 veces el riesgo de presentar lesiones precursoras de CG y no estar vinculado al régimen de salud aumenta 6,7 veces el riesgo de atrofia gástrica, (OR=4,27 y OR=6,72), respectivamente. Conclusión: El alelo mutante T (IL-1B-511) es un biomarcador de resistencia de los pobladores de Tumaco, de bajo riesgo de CG e infectados con H. pylori a padecer lesiones precursoras de CG.

Aim: To study the IL1B-511 and TNF-A-308 polymorphisms and their possible association with gastric cancer (GC) precursor lesions in a population infected with Helicobacter pylori (H. pylori) of low risk area of GC of Nariño. Material/method: 105 patients with symptoms of dyspepsia were included, 81 infected with H. pylori, (n=63) with non-atrophic gastritis and (n=18) with precursor lesions of GC of Tumaco: population of low risk of GC. Gastric lesions were classified by the Sydney System an H. pylori by Giemsa staining. The IL1B-511 and TNFA-308 polymorphisms were genotyped by PCR-RFLPs. Polymorphisms and their association with gastric lesions were evaluated by bivariate analysis and binomial logistic regression. Results: Patients carryng the mutant T allele (IL-1B-511) were not at risk of precursor lesions of malignancy (OR=0,7). The OR was not calculated for TNF-A-308, by fixing the normal allele G. Being a man and being infected with H. pylori increases 4,3 times the risk of presenting precursor lesions of GC and not being linked to the health regimen increases 6,7 times the risk of gastric atrophy, (OR=4,27 and OR=6,72), respectively. Conclusion: The mutant T allele (IL-1B-511) is a resistance biomarker of Tumaco residents, low risk of GC and infected with H. pylori to suffer precursor lesions of GC.

GBA mutations p.N370S and p. L444P are associated with Parkinson's disease in patients from Northern Brazil / Mutações p.N370S e p. L444P no gene GBA estão associadas com doença de Parkinson em pacientes do norte do Brasil

ABSTRACT Mutations of the GBA gene have been reported in patients with Parkinson's disease (PD) from a number of different countries, including Brazil. In order to confirm this pattern in a sample of PD patients from northern Brazil, we conducted a case-control study of the occurrence of the two most common mutations of the GBA gene (c.1226A>G; p.N370S and c.1448T>C; p.L444P) in a group of 81 PD patients and 81 control individuals, using PCR-RFLP, confirmed by the direct sequencing of the PCR products. In the patient group, three patients (3.7%) were heterozygous for the GBA c.1226A>G; p.N370S mutation, and three (3.7%) for GBA c.1448T>C; p.L444P Neither mutation was detected in the control group (p =0.0284). Patients with the c.1448T>C; p.L444P mutation showed a tendency to have an earlier disease onset, but a larger sample number is required to confirm this observation. Our results suggest an association between the GBA c.1226A>G; p.N370S and c.1448T>C; p.L444P mutations and the development of PD in the population of patients from the Northern Brazil.

RESUMO Mutações no gene GBA têm sido reportadas em pacientes com doença de Parkinson (DP) em diferentes países, incluindo o Brasil. Com o objetivo de confirmar esse padrão em uma amostra de pacientes com DP provenientes do Norte brasileiro, foi conduzindo esse estudo caso-controle investigando a frequência das duas mutações mais comuns do gene GBA (c.1226A>G; p.N370S e c.1448T>C; p.L444P) em um grupo de 81 pacientes com DP e 81 controles, usando PCR-RFLP e confirmado pelo sequenciamento direto de produtos de PCR. No grupo experimental, três pacientes (3,7%) foram heterozigotos para a mutação c.1226A>G; p.N370S e três (3,7%), para a mutação c.1448T>C; p.L444P Nenhuma das duas mutações foi detectada no grupo controle (p =0,0284). Pacientes com a mutação c.1448T>C; p.L444P demonstraram uma tendência a apresentar os sintomas mais precocemente, porém um número amostrai maior é necessário para confirmar essa observação. Nossos resultados sugerem uma associação entre essas duas mutações no gene GBA e o desenvolvimento de DP na população de pacientes do norte Brasileiro.

Chronic prostatitis alters the prostatic microenvironment and accelerates preneoplastic lesions in C57BL/6 mice

BACKGROUND: Chronic prostatitis has been supposed to be associated with preneoplastic lesions and cancer development. The objective of this study was to examine how chronic inflammation results in a prostatic microenvironment and gene mutation in C57BL/6 mice. METHODS: Immune and bacterial prostatitis mouse models were created through abdominal subcutaneous injection of rat prostate extract protein immunization (EAP group) or transurethral instillation of uropathogenic E. coli 1677 (E. coli group). Prostate histology, serum cytokine level, and genome-wide exome (GWE) sequences were examined 1, 3, and 6 months after immunization or injection. RESULT: In the EAP and E. coli groups, immune cell infiltrations were observed in the first and last months of the entire experiment. After 3 months, obvious proliferative inflammatory atrophy (PIA) and prostatic intraepithelial neoplasia (PIN) were observed accompanied with fibrosis hyperplasia in stroma. The decrease in basal cells (Cytokeratin (CK) 5+/p63+) and the accumulation of luminal epithelial cells (CK8+) in the PIA or PIN area indicated that the basal cells were damaged or transformed into different luminal cells. Hic1, Zfp148, and Mfge8 gene mutations were detected in chronic prostatitis somatic cells. CONCLUSION: Chronic prostatitis induced by prostate extract protein immunization or E. coli infection caused a reactive prostatic inflammation microenvironment and resulted in tissue damage, aberrant atrophy, hyperplasia, and somatic genome mutation.

A pioneering RET genetic screening study in the State of Ceará, Brazil, evaluating patients with medullary thyroid cancer and at-risk relatives: experience with 247 individuals

ABSTRACT Objective: Initial diagnosis of medullary thyroid carcinoma (MTC) is frequently associated with advanced stages and a poor prognosis. Thus, the need for earlier diagnoses and detection in relatives at risk for the disease has led to increased use of RET genetic screening. Subjects and methods: We performed RET screening in 247 subjects who were referred to the Brazilian Research Consortium for Multiple Endocrine Neoplasia (BRASMEN) Center in the State of Ceará. Direct genetic sequencing was used to analyze exons 8, 10, 11, and 13-16 in MTC index cases and specific exons in at risk relatives. Afterward, clinical follow-up was offered to all the patients with MTC and their affected relatives. Results: RET screening was performed in 60 MTC index patients and 187 at-risk family members. At the initial clinical assessment of the index patients, 54 (90%) were diagnosed with apparently sporadic disease and 6 (10%) diagnosed with hereditary disease. After RET screening, we found that 31 (52%) index patients had sporadic disease, and 29 (48%) had hereditary disease. Regarding at-risk relatives, 73/187 were mutation carriers. Mutations in RET codon 804 and the rare p.M918V mutation were the most prevalent. Conclusions: Performing RET screening in Ceará allowed us to identify a different mutation profile in this region compared with other areas. RET screening also enabled the diagnosis of a significant number of hereditary MTC patients who were initially classified as sporadic disease patients and benefited their relatives, who were unaware of the risks and the consequences of bearing a RET mutation.

Hepatitis B virus subgenotype C2- and B2-associated mutation patterns may be responsible for liver cirrhosis and hepatocellular carcinoma, respectively

The objective of this study was to examine hepatitis B virus (HBV) subgenotypes and mutations in enhancer II, basal core promoter, and precore regions of HBV in relation to risks of liver cirrhosis (LC) and hepatocellular carcinoma (HCC) in Southeast China. A case-control study was performed, including chronic hepatitis B (CHB; n=125), LC (n=120), and HCC (n=136). HBV was genotyped by multiplex polymerase chain reaction and subgenotyped by restriction fragment length polymorphism. HBV mutations were measured by DNA sequencing. HBV genotype C (68.2%) predominated and genotype B (30.2%) was the second most common. Of these, C2 (67.5%) was the most prevalent subgenotype, and B2 (30.2%) ranked second. Thirteen mutations with a frequency >5% were detected. Seven mutation patterns (C1653T, G1719T, G1730C, T1753C, A1762T, G1764A, and G1799C) were associated with C2, and four patterns (C1810T, A1846T, G1862T, and G1896A) were associated with B2. Six patterns (C1653T, G1730C, T1753C, A1762T, G1764A, and G1799C) were obviously associated with LC, and 10 patterns (C1653T, G1730C, T1753C, A1762T, G1764A, G1799C, C1810T, A1846T, G1862T, and G1896A) were significantly associated with HCC compared with CHB. Four patterns (C1810T, A1846T, G1862T, and G1896A) were significantly associated with HCC compared with LC. Multivariate regression analyses showed that HBV subgenotype C2 and C2-associated mutation patterns (C1653T, T1753C, A1762T, and G1764A) were independent risk factors for LC when CHB was the control, and that B2-associated mutation patterns (C1810T, A1846T, G1862T, and G1896A) were independent risk factors for HCC when LC was the control.

Hepatitis B virus infection in children, adolescents, and their relatives: genotype distribution and precore and core gene mutations / Infecção pelo vírus da hepatite B em crianças, adolescentes e seus familiares: distribuição dos genótipos e mutações no gene pré-core e core

INTRODUCTION:The objectives of this study were evaluate hepatitis B virus (HBV) serological markers in children and adolescents followed up at the Child Institute of the Hospital das Clínicas, Faculdade de Medicina de São Paulo, Universidade de São Paulo; identify chronic HBV carriers and susceptible individuals in the intrafamilial environment; characterize HBV genotypes; and identify mutations in the patients and household contacts. METHODS: Ninety-five hepatitis B surface antigen-positive children aged <19 years and 118 household contacts were enrolled in this study. Commercial kits were used for the detection of serological markers, and PCR was used for genotyping. RESULTS: Hepatitis B e antigen (HBeAg) was detected in 66.3% (63/95) of cases. Three of the 30 HBeAg-negative and anti-HBeAg-positive patients presented with precore mutations and 11 presented with mutations in the basal core promoter (BCP). Genotype A was identified in 39 (43.8%) patients, genotype D in 45 (50.6%), and genotype C in 5 (5.6%). Of the 118 relatives, 40 were chronic HBV carriers, 52 presented with the anti-HBc marker, 19 were vaccinated, and 7 were susceptible. Among the relatives, genotypes A, D, and C were the most frequent. One parent presented with a precore mutation and 4 presented with BCP mutations. CONCLUSIONS: Genotypes A and D were the most frequent among children, adolescents, and their relatives. The high prevalence of HBV in the families showed the possibility of its intrafamilial transmission.

INTRODUÇÃO: Os objetivos deste estudo foram: avaliar os marcadores sorológicos nas crianças e adolescentes acompanhadas no Instituto da Criança do Hospital das Clínicas, Faculdade de Medicina da Universidade de São Paulo (HC-FMUSP); identificar portadores crônicos do VHB e indivíduos suscetíveis no ambiente intrafamiliar; caracterizar o genótipo do VHB; observar a presença de cepas mutantes entre os pacientes e familiares estudados. MÉTODOS: Noventa e cinco crianças e adolescentes positivas para o antígeno de superfície do vírus da Hepatite B (AgHBs), menores de 19 anos, e 118 familiares foram envolvidos neste estudo. Foram utilizados kits comerciais para a pesquisa dos marcadores sorológicos e a PCR foi utilizada para genotipagem. RESULTADOS: O antígeno e do vírus da hepatite B (AgHBe) foi detectado em 66,3% (63/95) dos casos. Três dos 30 pacientes AgHBe negativo e anti-HBe positivo apresentaram mutação na região pré-core e 11 na região BCP. Em 39 (43,8%) pacientes, foi identificado o genótipo A, 45 (50,6%)o genótipo D e cinco (5,6%) o genótipo C. Dos 118 familiares estudados, 40 eram portadores crônicos do VHB, 52 tinham marcador sorológico de contato prévio e sete eram suscetíveis. Dentre os familiares AgHBs positivos, os genótipos A, D e C foram os mais frequentes. Um familiar apresentou mutação na região pré-core e quatro apresentaram mutação na região do BCP. CONCLUSÕES: Os genótipos A e D foram os mais frequentes dentre as crianças adolescentes e seus familiares. Alta frequência do VHB nos familiares mostrou a possibilidade de transmissão intrafamiliar.

Investigação de variantes gênicas de canais iônicos em pacientes com síndrome do QT longo / Investigation of ion channel gene variants in patients with long QT syndrome / Investigación de variantes génicas de canales iónicos en pacientes con síndrome del QT largo

FUNDAMENTO: A síndrome do QT longo (SQTL) é uma síndrome arrítmica herdada com aumento do intervalo QT e risco de morte súbita. Mutações nos genes KCNQ1, KCNH2 e SCN5A respondem por 90 por cento dos casos com genótipo determinado, e a genotipagem é informativa para aconselhamento genético e melhor manejo da doença. OBJETIVO: Investigação molecular e análise computacional de variantes gênicas de KCNQ1, KCNH2 e SCN5A associadas à SQTL em famílias portadoras da doença. MÉTODOS: As regiões codificantes dos genes KCNQ1, KCNH2 e SCN5A de pacientes com SQTL e familiares foram sequenciadas e analisadas utilizando o software Geneious ProTM. RESULTADOS: Foram investigadas duas famílias com critérios clínicos para SQTL. A probanda da Família A apresentava QTC = 562 ms, Escore de Schwartz = 5,5. A genotipagem identificou a mutação G1714A no gene KCNH2. Foi observado QTC = 521 ± 42 ms nos familiares portadores da mutação contra QTC = 391 ± 21 ms de não portadores. A probanda da Família B apresentava QTc = 551 ms, Escore de Schwartz = 5. A genotipagem identificou a mutação G1600T, no mesmo gene. A análise dos familiares revelou QTC = 497 ± 42 ms nos portadores da mutação, contra QTC = 404 ± 29 ms nos não portadores. CONCLUSÃO: Foram encontradas duas variantes gênicas previamente associadas à SQTL em duas famílias com diagnóstico clínico de SQTL. Em todos os familiares portadores das mutações foi observado o prolongamento do intervalo QT. Foi desenvolvida uma estratégia para identificação de variantes dos genes KCNQ1, KCNH2 e SCN5A, possibilitando o treinamento de pessoal técnico para futura aplicação na rotina diagnóstica.

BACKGROUND: The long QT syndrome (LQTS) is an inherited arrhythmia syndrome with increased QT interval and risk of sudden death. Mutations in genes KCNQ1, KCNH2 and SCN5A account for 90 percent of cases with genotype determined, and genotyping is informative for genetic counseling and better disease management. OBJECTIVE: Molecular investigation and computational analysis of gene variants of KCNQ1, KCNH2 and SCN5A associated with LQTS, in families with the disease. METHODS: The coding regions of genes KCNQ1, KCNH2 and SCN5A in patients with LQTS and their family members were sequenced and analyzed using Geneious ProTM software. RESULTS: Two families with clinical criteria for LQTS were investigated. The proband of Family A had QTC = 562 ms, Schwartz Score = 5.5. The genotyping identified the G1714A mutation in the KCNH2 gene. QTC = 521 ± 42 ms was observed in family members carrying the mutation against QTC = 391 ± 21 ms for non-carriers. The proband of Family B had QTc = 551 ms, Schwartz Score = 5.5. The genotyping identified the G1600T mutation, in the same gene. The analysis of family members revealed QTC = 497 ± 42 ms in mutation carriers, compared with QTC = 404 ± 29 ms in non-carriers. CONCLUSION: Two gene variants previously associated with LQTS were found in two families clinically diagnosed with LQTS. The prolongation of the QT interval was observed in all family members carrying the mutations. A strategy was developed to identify variants of genes KCNQ1, KCNH2 and SCN5A, making it possible to train technical staff for future application to diagnosis routine.

FUNDAMENTO: El síndrome del QT largo (SQTL) es un síndrome arrítmico heredado con aumento del intervalo QT y riesgo de muerte súbita. Mutaciones en los genes KCNQ1, KCNH2 y SCN5A responden por 90 por ciento de los casos con genotipo determinado, y el genotipaje es informativo para aconsejamiento genético y mejor manejo de la enfermedad. OBJETIVO: Investigación molecular y análisis computacional de variantes génicas de KCNQ1, KCNH2 y SCN5A asociadas a la SQTL en familias portadoras de la enfermedad. MÉTODOS: Las regiones codificantes de los genes KCNQ1, KCNH2 y SCN5A de pacientes con SQTL y familiares fueron secuenciadas y analizadas utilizando el software Geneious Pro®. RESULTADOS: Fueron investigadas dos familias con criterios clínicos para SQTL. La probanda de la Familia A presentaba QT C = 562 ms, Escore de Schwartz = 5,5. El genotipaje identificó la mutación G1714A en el gen KCNH2. Fue observado QT C = 521 ± 42 ms en los familiares portadores de la mutación contra QT C = 391 ± 21 ms de no portadores. La probanda de la Familia B presentaba QT C = 551 ms, Escore de Schwartz = 5. El genotipaje identificó la mutación G1600T, en el mismo gen. El análisis de los familiares reveló QT C = 497 ± 42 ms en los portadores de la mutación, contra QT C = 404 ± 29 ms en los no portadores. CONCLUSIÓN: Fueron encontradas dos variantes génicas previamente asociadas a la SQTL en dos familias con diagnóstico clínico de SQTL. En todos los familiares portadores de las mutaciones fue observada la prolongación del intervalo QT. Fue desarrollada una estrategia para identificación de variantes de los genes KCNQ1, KCNH2 y SCN5A, posibilitando el entrenamiento de personal técnico para futura aplicación en la rutina diagnóstica.

Diagnóstico de fibrose cística através de pesquisa genética expandida em paciente adulto com apresentação atípica / Diagnosis of cystic fibrosis using expanded genetic research in adult patient with atypical presentation

A Fibrose cística (FC) é uma desordem multissistêmica, caracterizada principalmente por doença pulmonar crônica e anormalidades gastrintestinais e nutricionais, que apresenta grande variabilidade de expressão entre os acometidos, sendo transmitida geneticamente por herança autossômica recessiva. O caso clínico apresentado mostra paciente feminina com sintomas respiratórios leves, função pancreática normal, teste de suor normal/limítrofe e pesquisa da mutação F508del negativa. O diagnóstico de fibrose cística foi confirmado através de pesquisa genética expandida, com identificação de duas mutações raras (p.A559T e p.D1152H). O caso relatado demonstra a importância da investigação genética na abordagem dos casos atípicos de FC, caracterizados pelo teste do suor normal/limítrofe, associados a sintomas respiratórios leves em uma faixa etária incomum para o diagnóstico da doença.

Cystic fibrosis is a multisystemic disorder characterized by chronic lung injury and gastrointestinal and nutrition abnormalities. It has a large variability of clinical presentations, being genetically transmitted by autossomic recessive heritage. The presenting case reports a female patient with mild respiratory symptoms, normal pancreatic function, normal/borderline sweat test and negative F508del mutation. The cystic fibrosis diagnose was confirmed with expanded genetic research, with the identification of two rare mutations (p.A559T and p.D1152H). The case report demonstrates the importance of the genetic investigation in the approach of atypical cystic fibrosis cases, characterized as normal/borderline sweat test, associated with mild respiratory symptoms and unusual age for the disease's diagnosis.

Neoplasias mieloproliferativas: revisão dos critérios diagnósticos e dos aspectos clínicos / Myeloproliferative neoplasms: a review of diagnostic criteria and clinical aspects

As síndromes mieloproliferativas crônicas, atualmente denominadas neoplasias mieloproliferativas (NMP), de acordo com a 4ª. edição da classificação da Organização Mundial da Saúde (OMS), são doenças clonais de célula-tronco hematopoética, nas quais há a proliferação aumentada de uma ou mais das séries mieloides (granulocítica, eritrocítica, megacariocítica ou mastocítica) com maturação eficaz. A progressão de todas é caracterizada por fibrose medular ou transformação leucêmica. Pela classificação da OMS, as NMP incluem: leucemia mieloide crônica (LMC), policitemia vera (PV), mielofibrose idiopática crônica (MF), trombocitemia essencial (TE), leucemia neutrofílica crônica (LNC), leucemia eosinofílica crônica não especificada(LEC), mastocitose (M) e neoplasia mieloproliferativa inclassificável (NMI). É interessante notar que tanto a LMC (BCR/ABL1) como PV, MF e TE (JAK2 V617F e éxon 12, MPLW515L/K) e M (KITD816V) tiveram suas bases moleculares desvendadas e apresentam em comum a ativação constitutiva de tirosino-quinase graças às mutações adquiridas pela célula-tronco hematopoética. A mutação JAK2 V617F é observada em mais de 90 por cento dos casos de PV, mas também em cerca de 50 por cento-60 por cento das MF e TE, levando ao questionamento de como uma única lesão molecular desencadeia três manifestações clínicas diversas. Já há evidências de que eventos genéticos e epigenéticos adicionais contribuem para a patogênese, tais como MPLW515L e MPLW515K. No presente manuscrito são apresentados os aspectos clínicos, a fisiopatologia e os critérios diagnósticos das diferentes NMP.

Chronic myeloproliferative disorders, currently called myeloproliferative neoplasms (MPN), according to the 4th edition of the World Health Organization (WHO) classification are clonal diseases of hematopoietic stem cells, in which there is increased proliferation of the myeloid series (granulocytic, erythrocytic, megakaryocytic series or mast cells) with effective maturation. The progression of all is characterized by marrow fibrosis or leukemic transformation. According to the WHO classification, the MPNs include: chronic myeloid leukemia (CML), polycythemia vera (PV), essential thrombocythemia (ET), idiopathic myelofibrosis (IM), chronic neutrophilic leukemia (CNL), chronic eosinophilic leukemia not otherwise categorized (CEL-NC), mastocytosis (M) and myeloproliferative neoplasm unclassifiable (MPNU). It is worth noting that the molecular basis of CML (BCR/ABL1), as well as PV,ET, IM (JAK2V617F and exon 12, MPL W515L/K) and M (KITD816V) have been identified and have, in common, constitutive activation of tyrosine kinase due to acquired hematopoietic stem cell defects. The JAK2V617F mutation is observed in around 90 percent of PV cases and in around 50-60 percent of IM and ET leading to the question why a single molecular lesion induces three different clinical manifestations. There is already evidence that additional genetic and epigenetic events contribute to the pathogenesis, including MPL W515L/K mutation. Some clinical aspects, the pathophysiology and diagnostic criteria of MPNs are presented in this paper.

Análise de pacientes com leucemia mieloide crônica com resistência primária ou secundária ao mesilato de imatinibe / Analysis of chronic myelogenous leukemia patients with primary or secondary resistance to imatinib mesylate

O mesilato de imatinibe, como terapia alvo, se revelou altamente eficiente na leucemia mielóide crônica. Um desafio é a resistência primária ou secundária, principalmente nas fases avançadas da doença. Na secundária, as mutações pontuais no domínio quinase ABL são o mecanismo mais frequente. Estudou-se no período de outubro de 2000 a dezembro de 2005, 112 pacientes no Serviço de Hematologia e Hemoterapia da Santa Casa de São Paulo. O objetivo foi caracterizar o perfil dos resistentes e pesquisar a presença de mutação. Encontrou-se maior porcentagem de resistentes nas fases mais avançadas. Foram fatores de risco para resistência na fase crônica o número de plaquetas superior a 450.000/mm³ pré-imatinibe ou plaquetas inferior a 50.000/mm³ durante o tratamento. A taxa de resposta hematológica completa e o tempo para obtenção foram semelhantes entre os resistentes e não resistentes. Observou-se menor sobrevida global nos resistentes. Destacaram-se dez pacientes resistentes com resposta citogenética completa pós 12 meses, "responsivos tardios", cuja freqüência de resposta hematológica e citogenética foi semelhante aos não resistentes (100 por cento). A sobrevida livre de progressão foi similar até aos 40 meses e a sobrevida global até aos 70 meses. A sobrevida global e as respostas foram superiores aos demais resistentes. Referente à pesquisa de mutação, analisou-se 22 resistentes, dos quais oito apresentaram mutação (36,4 por cento). Caracterizou-se maior risco para a condição de mutação, a presença de blastos no sangue periférico ao diagnóstico nos pacientes em fase crônica.

Imatinib mesylate, as target therapy, is highly efficient in chronic myelogenous leukemia. A challenge is primary and secondary resistance, particularly in the advanced phases of the disease. In secondary resistance, point mutations in the ABL dominion are the most common mechanism. From October 2000 to December 2005, 112 patients were investigated in the Hematology and Hemotherapy Service of Santa Casa of Sao Paulo. The aim was to characterize the profile of resistance and study the presence of the mutation. The majority of resistant patients were in the most advanced phases of the disease. Risk factors for resistance in the chronic phase were a platelet count higher than 450,000/mm3 before imatinib treatment or less than 50,000/mm3 during treatment. The total hematological response rate and the time to achieve this were similar between resistant and non-resistant patients. Lower overall survival was observed with resistance. It was notable that ten resistant patients had complete cytogenetic responses after 12 months (late responses) with both hematological and cytogenetic response rates similar to non-resistant patients (100 percent). Survival free from progression was similar up to 40 months and the overall survival rate was comparable up to 70 months. The overall survival and response to treatment were better than for the other resistant patients. In respect to the investigation of mutations, 22 resistant patients were investigated with eight presenting with the mutation (36.4 percent) The presence of blast cells in the peripheral blood at diagnosis of patients in the chronic phase was characterized as a higher risk factor for this mutation.

Fibrosis quística: la frontera del conocimiento molecular y sus aplicaciones clínicas / Cystic fibrosis: molecular update and clinical implications

Cystic fibrosis (CF) is an autosomal recessive disorder characterized by chronic pneumopathy, pancreatic insufficiency, elevated sweat chloride levels and male infertility. It is caused by defects in the CF trans membrane conductance regulator (CFTR) gene, which encodes a protein that functions as a chloride channel. The identification of the CF-causing gene was a landmark in molecular medicine. Currently, over 1,300 disease-causing mutations have been reported to the Cystic fibrosis genetic analysis consortium. ÁF508 mutation is the most common CF alíele, however a high heterogeneity of the CFTR mutations spectrum has been observed in populations, particularly in southern Europe and Latin America. Depending on the effect at the protein level, CFTR mutations can be divided in at least 5 classes. These mutations could cause totally (classes I-III) or partially (classes IV and V) loss of the protein function. The molecular defects resulting from different mutations in CFTR partially explain the clinical heterogeneity of the disease, suggesting the existence of modifier genes that are involved in modulating the phenotype and severity of the CF. In this review, we discuss the fundamental aspects and the recent progress that could give to the lector, the knowledge to understand the CFTR gene structure, the function of the CFTR protein, how CF mutations disrupt it, its phenotype consequences and finally, the strategies to design new therapies for the disease.

La fibrosis quística (FQ) es un padecimiento autosómico recesivo que se caracteriza por neumopatía crónica, insuficiencia pancreática, elevación de cloruros en sudor e infertilidad masculina. Esta patología es causada por la presencia de mutaciones en el gen CFTR que codifica para un canal de cloro denominado proteína reguladora de la conductancia transmembranal (CFTR). Hasta la fecha se han reportado alrededor de 1,300 mutaciones diferentes, cuya frecuencia varía entre los diversos grupos étnicos. Estas mutaciones condicionan la pérdida total (clases I, II y III) o parcial (clases IV y V) de la función de la proteína y causan un defecto en el transporte de electrólitos en la membrana apical de las células epiteliales. Con excepción de la función pancreática, las manifestaciones clínicas de la FQ son variables aun en pacientes con el mismo genotipo, por lo que la presencia de las diferentes mutaciones en el CFTR explica sólo parcialmente la heterogeneidad clínica de la FQ. Recientemente se ha propuesto que otros genes denominados genes modificadores participan en la gravedad del cuadro clínico. Así, la FQ es una enfermedad genética que resulta en un amplio espectro de manifestaciones clínicas que pueden ir desde muy leves hasta conducir a la muerte durante los primeros meses de vida, por lo que en algunos casos el diagnóstico es sumamente complejo. En los últimos años, el gran alud de conocimientos ha permitido entender el defecto básico de la enfermedad y los mecanismos que la condicionan, por lo que en esta revisión se discuten los fundamentos para el entendimiento de la fisiopatología de la FQ, desde los aspectos clínicos hasta los avances moleculares más recientes.

Prevalência de genótipos e de mutantes pré-core A-1896 do vírus da hepatite B e suas implicações na hepatite crônica, em uma população da Amazônia oriental / Prevalence of hepatitis B virus genotypes and the occurrence of precore mutation A-1896 and to correlate them with the clinical presentation of chronic hepatitis, in a population group of the eastern Amazon region

A infecção pelo virus da hepatite B apresenta amplo espectro de manifestações clínicas. Objetivando conhecer os genótipos do HBV mais prevalentes e determinar a ocorrência da mutação pré-core A-1896, em uma população da Amazônia oriental, correlacionando com o diagnóstico clínico, foram selecionados 51 pacientes portadores crônicos de HBsAg e HBV-DNA positivos e divididos em três grupos: grupo A (n=14, pacientes assintomáticos); grupo B (n=20, sintomáticos HBeAg positivos) e grupo C (n=17, sintomáticos HBeAg negativos), sendo usado o sequenciador automático ABI modelo 377 para identificação de genótipos e mutantes pré-core. Os resultados evidenciaram o genótipo A como o mais prevalente, 81,8%, 89,5% e 93,7%, nos grupos A, B e C, respectivamente. A mutação pré-core A-1896 foi encontrada em 11,5% (3/26), sendo todos assintomáticos. Concluiu-se que na população estudada o genótipo A foi o mais prevalente e houve baixa ocorrência do mutante pré-core A-1896, ambos não se constituindo fatores agravantes da doença hepática.

Hepatitis B virus (HBV) infection presents itself with a variety of clinical manifestations. The present work aims to describe the prevalence of HBV genotypes and the occurrence of precore mutation A-1896 in a population group of the Eastern Amazon region of Brazil and to correlate them with the clinical presentation of chronic HBV infection. 51 HBsAg carriers (HBV-DNA positive) were selected and divided into three groups: A (14 asymptomatic subjects), B (20 HBeAg positive symptomatic patients) and C (17 HBeAg negative symptomatic patients). Using an automa ed DNA sequencer ABI model 377 by sequencing for determined of genotypes and precore mutation. The results showed that the genotype A was the most commonly found (81,1%, 89,5% and 93,7% in groups A, B and C, respectively) and precore mutation A-1896 was described in 11,5% (3/26) of group A subjects. Genotype A of HBV was the most prevalent (89,1%) and low occurrence of precore mutation A-1896, both not associate with the worst outcome of the chronic infection of HBV.