Screening for germline BRCA1, BRCA2, TP53 and CHEK2 mutations in families at-risk for hereditary breast cancer identified in a population-based study from Southern Brazil

Abstract In Brazil, breast cancer is a public health care problem due to its high incidence and mortality rates. In this study, we investigated the prevalence of hereditary breast cancer syndromes (HBCS) in a population-based cohort in Brazils southernmost capital, Porto Alegre. All participants answered a questionnaire about family history (FH) of breast, ovarian and colorectal cancer and those with a positive FH were invited for genetic cancer risk assessment (GCRA). If pedigree analysis was suggestive of HBCS, genetic testing of the BRCA1, BRCA2, TP53, and CHEK2 genes was offered. Of 902 women submitted to GCRA, 214 had pedigrees suggestive of HBCS. Fifty of them underwent genetic testing: 18 and 40 for BRCA1/BRCA2 and TP53 mutation screening, respectively, and 7 for CHEK2 1100delC testing. A deleterious BRCA2 mutation was identified in one of the HBOC probands and the CHEK2 1100delC mutation occurred in one of the HBCC families. No deleterious germline alterations were identified in BRCA1 or TP53. Although strict inclusion criteria and a comprehensive testing approach were used, the suspected genetic risk in these families remains unexplained. Further studies in a larger cohort are necessary to better understand the genetic component of hereditary breast cancer in Southern Brazil

Characterisation of Innate Fungal Recognition in the Lung

The innate recognition of fungi by leukocytes is mediated by pattern recognition receptors (PRR), such as Dectin-1, and is thought to occur at the cell surface triggering intracellular signalling cascades which lead to the induction of protective host responses. In the lung, this recognition is aided by surfactant which also serves to maintain the balance between inflammation and pulmonary function, although the underlying mechanisms are unknown. Here we have explored pulmonary innate recognition of a variety of fungal particles, including zymosan, Candida albicans and Aspergillus fumigatus, and demonstrate that opsonisation with surfactant components can limit inflammation by reducing host-cell fungal interactions. However, we found that this opsonisation does not contribute directly to innate fungal recognition and that this process is mediated through non-opsonic PRRs, including Dectin-1. Moreover, we found that pulmonary inflammatory responses to resting Aspergillus conidia were initiated by these PRRs in acidified phagolysosomes, following the uptake of fungal particles by leukocytes. Our data therefore provides crucial new insights into the mechanisms by which surfactant can maintain pulmonary function in the face of microbial challenge, and defines the phagolysosome as a novel intracellular compartment involved in the innate sensing of extracellular pathogens in the lung

Full-Exon Pyrosequencing Screening of BRCA Germline Mutations in Mexican Women with Inherited Breast and Ovarian Cancer

Hereditary breast cancer comprises 10% of all breast cancers. The most prevalent genes causing this pathology are BRCA1 and BRCA2 (breast cancer early onset 1 and 2), which also predispose to other cancers. Despite the outstanding relevance of genetic screening of BRCA deleterious variants in patients with a history of familial cancer, this practice is not common in Latin American public institutions. In this work we assessed mutations in the entire exonic and splice-site regions of BRCA in 39 patients with breast and ovarian cancer and with familial history of breast cancer or with clinical features suggestive for BRCA mutations by massive parallel pyrosequencing. First we evaluated the method with controls and found 41–485 reads per sequence in BRCA pathogenic mutations. Negative controls did not show deleterious variants, confirming the suitability of the approach. In patients diagnosed with cancer we found 4 novel deleterious mutations (c.2805_2808delAGAT and c.3124_3133delAGCAATATTA in BRCA1; c.2639_2640delTG and c.5114_5117delTAAA in BRCA2). The prevalence of BRCA mutations in these patients was 10.2%. Moreover, we discovered 16 variants with unknown clinical significance (11 in exons and 5 in introns); 4 were predicted as possibly pathogenic by in silico analyses, and 3 have not been described previously. This study illustrates how massive pyrosequencing technology can be applied to screen for BRCA mutations in the whole exonic and splice regions in patients with suspected BRCA-related cancers. This is the first effort to analyse the mutational status of BRCA genes on a Mexican-mestizo population by means of pyrosequencing

RELATO DE CASO: TRANSFUSÃO DE HEMOCOMPONENTE RH POSITIVO EM PACIENTE TRANSPLANTADA RH NEGATIVO

Introdução: O sistema Rh é considerado o sistema eritrocitário mais polimórfico de todos os já identificados , devido a imunogenicidade de seus antígenos, especialmente o antígeno D, até mesmo um pequeno volume de glóbulos vermelhos D-positivo, transfundidos em indivíduo D-negativo, predispõe a uma grande chance de desenvolver anticorpos. Aproximadamente, 80% dos indivíduos Rh negativo que recebem sangue Rh positivo irão produzir anticorpos anti-D após o primeiro contato Acredita-se na importância da rotina de investigação pré-tranfusional para o sucesso clínico e hematológico do paciente, entretanto, erros durante este processo, podem acarretar riscos e comprometer de forma significativa a vida do paciente. Objetivos: Relatar o caso de uma paciente Rh Negativo, submetida à transplante hepático, que recebeu transfusão de concentrado de hemácias (CH) Rh positivo em seu pós operário. Relato de caso: Paciente do sexo feminino, 42 anos, transplantada de fígado, realizou exames laboratoriais e constatou a queda da hemoglobina, no pós-operatório imediato. Paciente com tipagem A Negativo, resultados de Pesquisa de Anticorpo Irregular (PAI) negativo Teste de Coombs direto (TAD) positivo. Transfundiu, aproximadamente, 100 ml de CH. Após a infusão deste volume, foi constatado erro ao enviar CH de Rh Positivo, sendo então, suspensa imediatamente a transfusão. A notificação foi realizada em tempo real, sinalizada pela equipe médica e de enfermagem. Paciente foi monitorada pelo período de 30 dias, com a avaliação médica e laboratorial, testes de compatibilidade e reação transfusional, alimentados diariamente nos canais de sistema informatizado. Nao houve necessidade de transfusao de qualquer hecomponente durante a internaçao- Nao houve alteraçao em provas de hemolise. Discussão: Mesmo com ferramentas de segurança do processo transfusional, tivemos um evento que culminou com a transfusao de hemacias RhD incompativeis. Houve revisao deste processo com toda equipe e solicitado alteraçao em nosso sistema (SBS) para que em situaçoes de extrema urgência, haja sinalizaçao de incompatibilidade de RhD. Entretanto, não foi sensibilizada por hemacias RhD+ e nem apresentou PAI positivo, contrariando a alta frequência de sensibilização presente na literatura. Entedemos que o momento relacionado a supressao imune pos transplante possa ter corroborado o nosso resultado de PAI negativo. Conclusão: Sabe-se da importância de novas ferramentas que possam prevenir e garantir a segurança do paciente. Desta forma, erros muitas vezes corroboram para uma melhora de processo laboratorial e sistemático, proporcionando evolução significativa na qualidade da conduta transfusional