Single-nucleotide polymorphisms of GSK3B, GAB2 and SORL1 in late-onset Alzheimer's disease: interactions with the APOE genotype

In this study, we investigated the associations between single-nucleotide polymorphisms in GAB2 (rs2373115), GSK3B (rs6438552) and SORL1 (rs641120) and Alzheimer's disease (AD), both alone and in combination with the APOE*4 allele.

Epidermal growth factor receptor and KRAS mutations in Brazilian lung cancer patients

OBJECTIVE: Epidermal growth factor receptor is involved in the pathogenesis of non-small cell lung cancer and has recently emerged as an important target for molecular therapeutics. The KRAS oncogene also plays an important role in the development of lung cancer. The aim of this study was to evaluate the frequency of epidermal growth factor receptor and KRAS mutations in a population of Brazilian patients with non-small cell lung cancer. METHODS: A total of 207 specimens from Brazilian patients with non-small cell lung cancer were analyzed for activating epidermal growth factor receptor and KRAS somatic mutations, and their associations with clinicopathological characteristics (including age, gender, ethnicity, smoking habits, and histological subtype) were examined. RESULTS: We identified 63 cases (30.4%) with epidermal growth factor receptor mutations and 30 cases (14.6%) with KRAS mutations. The most frequent epidermal growth factor receptor mutation we detected was a deletion in exon 19 (60.3%, 38 patients), followed by an L858R amino acid substitution in exon 21 (27%, 17 patients). The most common types of KRAS mutations were found in codon 12. There were no significant differences in epidermal growth factor receptor or KRAS mutations by gender or primary versus metastatic lung cancer. There was a higher prevalence of KRAS mutations in the non-Asian patients. Epidermal growth factor receptor mutations were more prevalent in adenocarcinomas than in non-adenocarcinoma histological types. Being a non-smoker was significantly associated with the prevalence of epidermal growth factor receptor mutations, but the prevalence of KRAS mutations was significantly associated with smoking. CONCLUSIONS: This study is the first to examine the prevalence of epidermal growth factor receptor and KRAS mutations in a Brazilian population sample with non-small cell lung cancer.

MammaGene: ensaio quantitativo de 21 genes para prognóstico do câncer de mama receptor de estrogênio positivo / MammaGene®: a quantitative 21-gene assay for prognostic of breast cancer estrogen receptor-positive

Objetivos: Padronizar em nosso meio um ensaio que analisa, por RT-PCR, 21 genes e descrever a experiência inicial com 95 casos consecutivos de carcinoma inicial de mama receptor de estrogênio positivo. Métodos: O teste foi desenvolvido a partir dos relatos publicados por Cronin et al. (2004) e Paik et al. (2004) para a avaliação da expressão de genes em tecido fixado em formalina e incluído em parafina. O teste foi aplicado em uma coorte consecutiva de 95 amostras de câncer de mama receptor de estrogênio positivo e os escores finais foram comparados com a idade da paciente, O tamanho do tumor, o tipo e o grau histológico, expressão imunoistoquímica do receptor de estrogênio, índice de Ki67 e subtipo molecular. Resultados: Os escores finais variaram de 3 a 90 e as categorias de risco de recorrência em dez anos foram: baixa (34 casos), intermediária (38 casos) e alta (23 casos). Não houve associação das categorias de risco com idade, comprometimento linfonodal e tipo histológico. A media do tamanho dos tumores foi maior no grupo de alto escore (2,0 versus 1,2 cm). Observou-se associação entre o escore obtido pelo teste e grau histológico, Ki-67, nível de expressão de receptor de estrogênio e subtipo molecular. Conclusão: A realização do teste de 21 genes foi factível em nosso meio. Alem disso, os dados preliminares, aliados aos dados da literatura, sugerem que tal teste pode ser uma ferramenta útil na avaliação do risco de recorrência a distância em câncer de mama receptor de estrogênio positivo. No entanto, estudos adicionais são necessários para comparar os resultados deste trabalho com séries amplas publicadas na literatura.

Objectives: To standardize a homemade RT-PCR-based 21-gene assay and to describe the preliminary experience with 95 early positive estrogen receptor breast cancer consecutive cases. Methods: The test was developed using the reports described by Cronin et al. (2004) and Paik et al. (2004) for the evaluation of gene expression in fixed, paraffin-embedded tumor tissue. The test was performed in a consecutive cohort of 95 positive estrogen receptor breast carcinomas, and the final scores were compared with the patient's age, tumor size, histological type, histological degree, estrogen receptor immunohistochemical expression, Ki-67 expression, and molecular luminal subtype. Results: Final scores ranged from 3 to 90 and risk categories of recurrence in ten years were: low (34 cases), intermediate (38 cases), and high (23 cases). There was no association between score categorical distribution and age, lymph node status, or histological type. Mean tumor size was higher in the high score group (2.0 versus 1.2 cm). We have observed an overall concordance between the score obtained by the test, and the histological degree, Ki-67, estrogen receptor level, and molecular subtype. Conclusion: The developed 21-gene assay is a feasible test to be performed in a homemade setting. Besides, the preliminary data from this study suggest, in comparison with data from the literature, that this test has the potential to be a useful tool to evaluate the risk of breast cancer distant recurrence. However, further data are necessary in order to compare this paper's results with larger series published in the literature.

Clinical and biological predictors of Alzheimer's disease in patients with amnestic mild cognitive impairment / Preditores clínicos e biológicos da evolução para doença de Alzheimer em pacientes com comprometimento cognitivo leve amnéstico

OBJECTIVE: To identify predictors of the progression from pre-dementia stages of cognitive impairment in Alzheimer's disease is relevant to clinical management and to substantiate the decision of prescribing antidementia drugs. METHOD: Longitudinal study of a cohort of elderly adults with amnestic mild cognitive impairment and healthy controls, carried out to estimate the risk and characterize predictors of the progression to Alzheimer's disease. RESULTS: Patients with amnestic mild cognitive impairment had a higher risk to develop Alzheimer's disease during follow-up (odds ratio = 4.5, CI95 percent [1.3-13.6], p = 0.010). At baseline, older age, lower scores on memory tests and presence of the APOE*4 allele predicted the progression from amnestic mild cognitive impairment to Alzheimer's disease. In a sub sample of amnestic mild cognitive impairment patients, those who progressed to Alzheimer's disease had lower cerebrospinal fluid concentrations of amyloid-beta peptide (Aβ42, p = 0.020) and higher concentrations of total TAU (p = 0.030) and phosphorylated TAU (p = 0.010), as compared to non-converters. DISCUSSION: This is the first Brazilian study to report cerebrospinal fluid biomarkers in the prediction of the conversion from MCI to Alzheimer's disease. Our data are in accordance with those reported in other settings. The measurement of cerebrospinal fluid total-TAU, phospho-TAU and Aβ42 may help identify patients with mild cognitive impairment at higher risk for developing Alzheimer's disease.

OBJETIVO: A identificação de preditores da conversão para a doença de Alzheimer em pacientes com comprometimento cognitivo leve é relevante para o manejo clínico e para decidir sobre a prescrição de drogas antidemência. MÉTODO: Estudo longitudinal em coorte de indivíduos idosos com comprometimento cognitivo leve amnéstico e controles saudáveis; estimativa do risco da progressão para doença de Alzheimer nos dois grupos; determinação das variáveis preditivas desse desfecho. RESULTADOS: Pacientes com comprometimento cognitivo leve amnéstico apresentaram maior risco de desenvolver doença de Alzheimer ao longo do seguimento (odds ratio = 4,5, CI95 por cento [1,3-13,6], p = 0,012). Na avaliação inicial, idade mais avançada, escores mais baixos nos testes cognitivos e do alelo APOE*4 foram preditores da conversão do comprometimento cognitivo leve amnéstico para doença de Alzheimer. Em uma subamostra de pacientes com comprometimento cognitivo leve amnéstico, aqueles que progrediram para doença de Alzheimer tinham concentrações liquóricas mais baixas do peptídeo beta-amilóide (Aβ42, p = 0,020) e mais altas da proteína TAU total (p = 0,030) e TAU fosforilada (p = 0,010) do que os pacientes que não progrediram para doença de Alzheimer. DISCUSSÃO: Este é o primeiro estudo brasileiro com biomarcadores liquóricos a relatar preditores da conversão comprometimento cognitivo leve-doença de Alzheimer. Nossos dados biológicos (aumento de TAU total e fosfo-TAU; redução de Aβ42), e podem auxiliar na identificação dos pacientes com comprometimento cognitivo leve com maior risco de evolução para demência.

Potential economic impact of the 21-gene expression assay on the treatment of breast cancer in brazil / Potencial impacto econômico do painel de expressão de 21 genes no tratamento adjuvante do câncer de mama no Brasil

OBJECTIVE: The 21-gene expression assay may support the decision regarding use of chemotherapy in early breast cancer. We sought to investigate the potential impact of incorporating the 21-gene expression assay into private practice in Brazil, from the perspective of third party payers. METHODS: We conducted a web-based survey with 30 (of a total of approximately 700) Brazilian medical oncologists, who were stratified by State according to the proportion of patients with breast cancer and private health insurance. We evaluated the possible treatment of first choice for patients with lymph-node-negative, estrogen-receptor-positive breast cancer, regardless of menopausal status. Interviewees were not aware of the objective of the study. Responses permitted a quantitative assessment of the care patterns regarding use of different chemotherapy regimens, type of premedication, use of growth factors, and use of intravenous antibiotics for febrile neutropenia. We calculated medication costs using the manufacturer's recommended prices. Other direct medical expenses, indirect medical costs, and non-medical costs were not included. RESULTS: Considering a hypothetical cohort of 100 patients without access to the 21-gene expression assay, the survey showed that 84 patients would receive chemotherapy. Reclassifying patient eligibility for chemotherapy according to the 21-gene expression assay would lower this number to 49. For a hypothetical cohort of 100 patients with access to the test, US$ 79,361.43 would be saved in main direct medical costs. Such results, however, would greatly vary according to tumor size: the 21-gene expression assay could increase direct medical costs in T1 tumors, and decrease costs in cases with T >2 cm. CONCLUSION: Considering the current price for the 21-gene expression assay in Brazil, our economic analysis suggests that such testing is an overall cost-saving, from the perspective of third party payers. Further, optimal ...

OBJETIVO: O índice de recorrência (IR), também conhecido como painel de 21 genes, pode apoiar decisões com relação ao uso de quimioterapia (QT) no câncer de mama precoce. Procuramos investigar o impacto potencial da incorporação do IR na prática privada no Brasil, a partir da perspectiva das fontes pagadoras. MÉTODOS: Conduzimos uma pesquisa com 30 oncologistas brasileiros (de um total de aproximadamente 700), que foram estratificados por Estado de acordo com a proporção de pacientes com câncer de mama e com cobertura pelo sistema de saúde suplementar. Avaliamos o tratamento de primeira escolha para pacientes com câncer de mama com axila negativa e expressão positiva do receptor de estrógeno, independente do estado menopausal. Os entrevistados não estavam cientes do objetivo do estudo. As respostas permitiram uma avaliação quantitativa dos padrões de cuidado, considerando o uso de diferentes regimes de QT, o tipo de pré-medicações, o uso de fatores de crescimento e o tratamento hospitalar da neutropenia febril. Calculamos o custo dos medicamentos usando o Brasíndice, e o custo do IR foi fixado em R$ 3.900,00 (MammaGene®). Outras despesas médicas diretas, custos médicos indiretos e custos não-médicos não foram considerados. RESULTADOS: Numa corte hipotética de 100 pacientes sem acesso ao teste de IR, 84 iriam receber quimioterapia. Reclassificando a elegibilidade das pacientes para QT de acordo com o IR, esse número cairia para 49. Para uma coorte hipotética de 100 pacientes com acesso ao IR, seriam economizados R$ 134.915,00 em despesas médicas diretas. CONCLUSÃO: Considerando o preço atual para avaliação do IR no Brasil, nossa análise econômica sugere que este teste economizaria custos, pela perspectiva das fontes pagadoras do setor privado. Além disso, o uso otimizado de recursos poderia requerer o emprego do painel de 21 genes de forma racional.