Characterization of Patients with Breast Cancer and National Comprehensive Cancer Network Criteria for Performing BRCA1 and BRCA2 Genetic Test / Caracterização de Pacientes com Câncer de Mama e Critérios da National Comprehensive Cancer Network para Realização do Teste Genético BRCA1 e BRCA22 / Caracterización de Pacientes con Cáncer de Mama y Criterios de la National Comprehensive Cancer Network para Realizar Prueba Genética de BRCA1 y BRCA

Introduction: Approximately 10% of breast cancer cases are attibutable to germinative mutations in susceptibility genes, including BRCA1, BRCA2 and others. The National Comprehensive Cancer Network (NCCN) recommends screening women with breast cancer for mutations in BRCA1/2 in defined scenarios. However, these genetic tests are unavailable at the Brazilian Public Health System (SUS). Objective: This study aimed to characterize women with breast cancer and define the criteria for performing BRCA1/2 test. Method: Quantitative, descriptive, analytic, and retrospective study. Medical records of women diagnosed by SUS with breast cancer between January 2016 and December 2018 were analyzed through the software JAMOVI (version 2.3 - 2022). Results: A total of 245 women were diagnosed. According to NCCN guidelines, 97 women met the criteria for performing BRCA1/2 test, with mean age of 47 years old, predominantly white (90,7%), with comorbidities (55.6%), premenopausal (59.8%), diagnosed in early stages 0 - IIb (68.2%) and 48.4% had familial history of breast cancer. Most frequent histology and molecular subtype was invasive ductal carcinoma (87.2%) and luminal type (59.8%). Conclusion: A significant number of women diagnosed by SUS had indication for BRCA1/2 test. These women are younger, had fewer comorbidities, not menopausal, and differ in terms of the molecular subtype when compared with those without indication for performing the test

Introdução: Aproximadamente 10% dos casos de câncer de mama são atribuíveis a mutações germinativas em genes de suscetibilidade, incluindo BRCA1 e BRCA2. A National Comprehensive Cancer Network (NCCN) recomenda a triagem de mulheres com câncer de mama para mutações em BRCA1/2 em cenários definidos. No entanto, esses testes genéticos não estão disponíveis no Sistema Único de Saúde (SUS). Objetivo: Caracterizar as mulheres com câncer de mama e definir os critérios para realização do teste BRCA1/2. Método: Estudo quantitativo, descritivo, analítico e retrospectivo. Foram analisadosprontuários de mulheres com diagnóstico de câncer de mama pelo SUS entre janeiro de 2016 e dezembro de 2018, por meio do software JAMOVI (versão 2.3 - 2022). Resultados: Foram diagnosticadas 245 mulheres. De acordo com as diretrizes da NCCN, 97 mulheres atenderam aos critérios para realizar o teste BRCA1/2, com idade média de 47 anos, predominantemente brancas (90,7%), com comorbidades (55,6%), na pré-menopausa (59,8%), diagnosticadas nos estágios iniciais 0 - IIb (68, 2%), e 48,4% tinham histórico familiar de câncer de mama. A histologia e o subtipo molecular mais frequentes foram carcinoma ductal invasivo (87,2%) e tipo luminal (59,8%). Conclusão: Considerando os critérios da NCCN, um número significativo de mulheres diagnosticadas pelo SUS teve indicação para realização do teste BRCA1/2. Essas mulheres são mais jovens, têm menos comorbidades, estão em período pré-menopausa mais frequentemente e diferem quanto ao subtipo molecular quando comparadas àquelas sem indicação de realização do exame. Palavras-chave: neoplasias da mama; neoplasias ovarianas; síndrome hereditária de câncer de mama e ovário; genes, BRCA1

Introducción: Aproximadamente el 10% de los casos de cáncer de mama son atribuibles a mutaciones germinales en genes de susceptibilidad, incluidos BRCA1 y BRCA2. La National Comprehensive Cancer Network (NCCN) recomienda la detección de mutaciones BRCA1/2 en mujeres con cáncer de mama en entornos definidos. Sin embargo, estas pruebas genéticas no están disponibles en el Sistema Único de Salud (SUS). Objetivo: Caracterizar mujeres con cáncer de mama y definir los criterios para la realización de la prueba BRCA1/2. Método: Estudio cuantitativo, descriptivo, analítico y retrospectivo. Las historias clínicas de las mujeres diagnosticadas con cáncer de mama entre enero de 2016 y diciembre de 2018, usuarias del SUS, fueron analizadas mediante el software JAMOVI (versión 2.3 - 2022). Resultados: 245 mujeres fueron diagnosticadas. Según las pautas de NCCN, 97 mujeres cumplieron con los criterios para someterse a la prueba BRCA1/2. Las mujeres con indicación para la prueba tenían un promedio de edad de 47 años, eran predominantemente blancas (90,7%), con comorbilidades (55,6%), premenopáusicas (59,8%), diagnosticadas en estadios tempranos 0 - IIb (68,2%) y 48,4% tenía antecedentes familiares de cáncer de mama. Los subtipos histológicos y moleculares más frecuentes fueron el carcinoma ductal invasivo (87,2%) y el tipo luminal (59,8%). Conclusión: Considerando los criterios de la NCCN, un número significativo de mujeres, usuarias del SUS, fueron designadas para hacer la prueba BRCA1/2. Estas mujeres son más jóvenes, tienen menos comorbilidades, están en el periodo de la premenopausia con mayor frecuencia y difieren en el subtipo molecular en comparación con aquellas sin orden de realizarse la prueba

Tamizaje para cáncer de mama con resonancia magnética en mujeres portadoras de mutaciones BRCA y no-BRCA / Magnetic resonance imaging breast cancer screening in women who are carriers of BRCA and non-BRCA gene mutations / Rastreamento de câncer de mama com ressonância magnética em mulheres com mutações BRCA e não BRCA

Introducción: la predisposición hereditaria causada por mutaciones patogénicas de la línea germinal (MPG) explica hasta el 10% de los cánceres de mama. Para reducir su impacto en mujeres mutadas se han propuesto diferentes estrategias, tales como las cirugías reductoras de riesgo o el screening con resonancia magnética (RM) de mamas. Métodos: en este estudio observacional retrospectivo se analizaron los registros de mujeres portadoras de MPG para evaluar las diferentes acciones tomadas luego del test genético. A las pacientes no mastectomizadas se les recomendó ingresar a un programa anual de cribado con RM y se evaluó el porcentaje de adherencia al plan, el número de biopsias efectuadas y el número de cánceres de mama detectados. Resultados: se incluyeron 134 mujeres con MPG, con una distribución en tercios iguales de los genes BRCA1, BRCA2 y genes no-BRCA. Entre las mutadas con indicación de seguimiento, 64% ingresaron al programa de cribado con RM. Las razones que llevaron a las mujeres a no ingresar al programa de seguimiento fueron: la oposición del médico tratante (53%), oposición de la paciente (38%), y falta de recursos (9%). Se realizaron seis biopsias por hallazgos en la RM entre las cuales se detectó un cáncer de mama. La incidencia de cáncer fue de 11 cada 1.000 mujeres-años de riesgo. Conclusiones: nuestro programa de seguimiento con RM de pacientes mutadas logró captar un porcentaje alto de candidatas. Una proporción significativa de las mujeres no ingresó debido la desaprobación del médico tratante o de la propia paciente. La evidencia obtenida revela una necesidad imperiosa de reforzar los programas educativos que destaquen la importancia del seguimiento con RM de las pacientes de alto riesgo en nuestro país.

Summary: Introduction: genetic propensity caused by germline pathogenic mutations explain up to 10% of breast cancer cases. Different strategies have been proposed to reduce its impact on women who are carriers of mutations, such as risk-reducing surgeries or breast magnetic resonance screening. Method: observational, retrospective study analyzing the medical records of women who are carriers of germline pathogenic mutations to assess the different measures taken after the genetic test. Non-mastectomized patients were advised to join an annual MRI screening program and the percentage of adherence to plan was evaluated, along with biopsies performed and the number of breast cancer cases detected. Results: 134 women carriers of germline pathogenic mutations were included in the study, with equal distributions in thirds for BRCA1, BRCA2 and non-BRCA genes. 64% of carriers of mutations who were subject to follow-up checkups joined the RMI screening program. The reasons why women failed to join the follow-up program were: the treating physician objected to the program (53%), the patients opposed to program (38%) and lack of resources (9%). Six biopsies were performed as a consequence of findings in the RMI, and one case of breast cancer was detected. Cancer incidence was 11 out of 1000 women - risk years. Conclusions: our RMI follow-up program for women who are carriers of mutations managed to attract a high percentage of candidates. A significant amount of women failed to join the program because of their treating physician's or their own disapproval. Evidence obtained reveals the dramatic need to reinforce educational programs that emphasize on the importance of RMI follow-up of high risk patients in our country.

Introdução: a predisposição hereditária causada por mutações germinativas patogênicas (GMP) explica até 10% dos cânceres de mama. Para reduzir seu impacto em mulheres com mutações, diferentes estratégias têm sido propostas, como cirurgias de redução de risco ou ressonância magnética (RM) das mamas. Métodos: neste estudo observacional retrospectivo, os registros de mulheres portadoras de MPG foram analisados para avaliar as diferentes ações tomadas após o teste genético. Pacientes não mastectomizadas foram recomendadas a entrar em um programa anual de triagem por ressonância magnética e foram avaliados o percentual de adesão ao plano, o número de biópsias realizadas e o número de cânceres de mama detectados. Resultados: foram incluídas 134 mulheres com MPG, com uma distribuição de terços iguais dos genes BRCA1, BRCA2 e não-BRCA. Entre as mulheres com mutações com indicação de acompanhamento, 64% entraram no programa de triagem por ressonância magnética. Os motivos que levaram as mulheres a não ingressarem ao programa de acompanhamento foram: oposição do médico assistente (53%), oposição da paciente (38%) e falta de recursos (9%). Seis biópsias foram realizadas devido a achados de ressonância magnética, entre os quais foi detectado um câncer de mama. A incidência de câncer foi de 11 por 1.000 mulheres-ano de risco. Conclusões: nosso programa de acompanhamento de ressonância magnética para pacientes com mutação conseguiu capturar uma alta porcentagem de candidatas. Uma proporção significativa de mulheres não entrou devido à falta de aprovação do médico assistente ou da própria paciente. As evidências obtidas revelam a necessidade urgente de reforçar programas educacionais que destaquem a importância do acompanhamento por RM de pacientes de alto risco no Uruguai.

Implicações éticas dos testes genéticos de suscetibilidade ao câncer de mama / Ethical implications of genetic testing of susceptibility to breast cancer / Implicaciones éticas de las pruebas genéticas de susceptibilidad al cáncer de mama

Resumo O câncer de mama representa um problema de saúde pública por ser a neoplasia maligna de maior incidência em mulheres no mundo. A forma hereditária corresponde a cerca de 5% a 10% de todos os casos e está diretamente relacionada à herança de mutações genéticas, sendo as principais nos genes supressores de tumor BRCA1 e BRCA2. A identificação dessas mutações é de extrema importância pelo elevado risco de desenvolvimento de câncer de mama nessa população, permitindo estratégias de rastreamento diferenciado e adoção de medidas de redução de risco. Entretanto, é importante e necessário refletir sobre os aspectos éticos relacionados ao uso indiscriminado de testes genéticos. O objetivo deste trabalho foi avaliar o conhecimento e a opinião de médicos de um centro de referência oncológico sobre a indicação dos testes genéticos de suscetibilidade ao câncer de mama mediante dilemas éticos aos quais são submetidos na prática médica.

Abstract Breast cancer is a public health problem because it is the malignant neoplasm with the highest incidence in women worldwide. The hereditary form corresponds to about 5% to 10% of all cases and is directly related to the inheritance of genetic mutations. The main ones occur in the BRCA1 and BRCA2 tumor suppressor genes. The identification of these mutations is extremely important because of the high risk of breast cancer development in this population, allowing differentiated screening strategies and the adoption of risk reduction measures. However, reflections on the ethical aspects related to the indiscriminate use of genetic testing are important and necessary. The objective of this study was to evaluate the knowledge and opinion of physicians of an oncology reference center on the indication of genetic tests for susceptibility to breast cancer given the ethical dilemmas to which they are submitted in medical practice.

Resumen El cáncer de mama representa un problema de salud pública, ya que es la neoplasia maligna con mayor incidencia en las mujeres de todo el mundo. La forma hereditaria corresponde a entre el 5% y el 10% de todos los casos y está directamente relacionada con la herencia de mutaciones genéticas, y las principales se dan en los genes supresores de tumores BRCA1 y BRCA2. La identificación de estas mutaciones es extremadamente importante debido al elevado riesgo de esta población de desarrollar cáncer de mama, además de permitir estrategias de rastreo diferenciadas y la adopción de medidas de reducción del riesgo. Sin embargo, es importante y necesario reflexionar sobre los aspectos éticos relacionados con el uso indiscriminado de las pruebas genéticas. El objetivo de este estudio fue evaluar el conocimiento y la opinión de los médicos de un centro oncológico de referencia sobre la indicación de las pruebas genéticas de susceptibilidad al cáncer de mama mediante los dilemas éticos a los que se ven sometidos en la práctica médica.

Presentación de Caso Clínico: Carcinoma de mama luego de mastectomía de reducción de riesgo en paciente con mutación BRCA1 / Case report: Breast carcinoma after risk reducing mastectomy in a BRCA+ patient

Las pacientes sanas portadoras de mutaciones patogénicas del gen BRCA1 tiene un riesgo muy elevado de desarrollar cáncer de mama y ovario, con cifras reportadas que ascienden a 84% y 59% respec- tivamente.¹ Esto motivó a implementar distintas medidas de segui- miento y de reducción de riesgo, como la mastectomía bilateral de reducción de riesgo (MRR) y la salpingo-ooforectomía de reducción de riesgo (SORR). Pero aún así, distintas experiencias publicadas re- fieren que en pacientes portadoras de mutacion BRCA1 sometidas a MRR, el riesgo subsiguiente de desarrollar un cáncer primario de mama puede llegar al 10%.2 Por otro lado, las técnicas de mastectomías en general han experi- mentado modificaciones en menos, conservando las estructuras te- gumentarias y el tejido adiposo que la recubre. Últimamente se ha expuesto que, con la guía de las imágenes, se puede resecar menos tejido aun, fundamentalmente en los contornos mamarios donde se observa tejido adiposo y nada (o muy escaso) tejido glandular.3 Esta recomendación hoy es empírica, ya que no hay evidencia de la segu- ridad oncológica de conservar estos tejidos

Correlation between the number of false positive variants and the quality of results using Ion Torrent PGM™ sequencing to screen BRCA genes / Correlación entre el número de variantes de falsos positivos y la calidad de los resultados en la secuenciación con Ion Torrent PGM™ para seleccionar genes BRCA

Abstract | Introduction: Next Generation Sequencing (NGS) is cost-effective and a faster method to study genes, but its protocol is challenging. Objective: To analyze different adjustments to the protocol for screening the BRCA genes using Ion Torrent PGM sequencing and correlate the results with the number of false positive (FP) variants. Materials and methods: We conducted a library preparation process and analyzed the number of FP InDels, the library concentration, the number of cycles in the target amplification step, the purity of the nucleic acid, the input, and the number of samples/Ion 314 chips in association with the results obtained by NGS. Results: We carried out 51 reactions and nine adjustments of protocols and observed eight FP InDels in homopolymer regions. No FP Single-Nucleotide Polymorphism variant was observed; 67.5% of protocol variables were jointly associated with the quality of the results obtained (p<0.05). The number of FP InDels decreased when the quality of results increased. Conclusion: The Ion AmpliSeq BRCA1/BRCA2 Community Panel had a better performance using four samples per Ion-314 chip instead of eight and the optimum number of cycles in the amplification step, even when using high-quality DNA, was 23. We observed better results with the manual equalization process and not using the Ion Library Equalizer kit. These adjustments provided a higher coverage of the variants and fewer artifacts (6.7-fold). Laboratories must perform internal validation because FP InDel variants can vary according to the quality of results while the NGS assay should be validated with Sanger.

Resumen | Introducción. La secuenciación de nueva generación es un método rentable y rápido para el estudio de los genes, pero su protocolo entraña desafíos. Objetivo. Investigar diferentes ajustes del protocolo de selección de los genes BRCAmediante secuenciación de Ion Torrent PGM™ y correlacionar los resultados con el número de variantes de falso positivo. Materiales y métodos. El proceso de preparación de la biblioteca, el número de falsos positivos InDels, la concentración de la biblioteca, el número de ciclos en el paso de amplificación de objetivos, la pureza del ácido nucleico, la entrada y el número de muestras por chip del Ion-314 se analizaron en asociación con los resultados obtenidos por secuenciación de nueva generación secuenciación de nueva generación. Resultados. Se hicieron 51 reacciones y nueve ajustes de los protocolos, y se observaron ocho falsos positivos InDels en las regiones de homopolímeros. No se observó ninguna variante de polimorfismo de nucleótido simple falso positivo. En 67,5 % de los casos, las variables de protocolo en su conjunto se asociaron con la calidad de los resultados obtenidos (p<0,05). El número de falsos positivos InDels disminuyó al aumentar la calidad de los resultados. Conclusiones. El panel comunitario Ion AmpliSeq BRCA1/BRCA2 tuvo un mejor rendimiento, con cuatro muestras por chip Ion-314 en lugar de ocho, y el número de ciclos en el paso de amplificación, incluso con ADN de alta calidad, fue mejor con 23. Se observaron mejores resultados con el proceso de ecualización manual y sin el uso del kit Ion Library Equalizer. Estos ajustes proporcionaron una mayor cobertura de las variantes y menos artefactos. Los laboratorios deben realizar la validación interna porque las variantes de falsos positivos InDel pueden variar según la calidad de los resultados. La secuenciación de próxima generación debe validarse con Sanger.

Presença da mutação do gene BRCA1 em cadelas com tumores mamários malignos / Presence of BRCA1 gene mutation in bitches with malignant mammary tumors

Mammary tumors (MTs) in bitches are similar to breast cancers in women. Thus, they can be used as a model for human breast cancer and findings can be extrapolated for use in human medicine. BRCA1 is a tumor suppressor gene. When the gene has a mutation, it cannot repair damaged DNA, which causes genetic instability and tumorigenesis. Therefore, we aimed to study the frequency of single nucleotide polymorphisms (SNPs) in the BRCA1 gene that are associated with distinct histological types of malignant MT in bitches. The study population consisted of 91 bitches, including a control group of 6 animals with healthy mammary glands and 85 animals with MTs. All animals underwent a presurgery evaluation consisting of a questionnaire administered to the person responsible for the animal, a physical examination, collection of peripheral blood for hematological and serum biochemistry evaluations, an electrocardiogram, and a preanesthesia evaluation. In addition, distant metastasis was studied via chest radiography and abdominal ultrasound. After evaluations were complete, the animals that could undergo surgery were administered general anesthesia and underwent a mastectomy or mammary gland sample collection. Histopathological examination and molecular analysis were performed to identify mutations in the BRCA1 gene. Histopathological examinations found 10 different types of malignant tumors in 36 sick animals. Tumor samples plus samples from the 6 control animals were subjected to DNA extraction, polymerase chain reaction (PCR) analysis, and genetic sequencing. The tumor with the highest incidence (33.33%) was a complex carcinoma, followed by carcinoma in mixed tumor (13.88), tubular carcinoma (13.88) and carcinosarcoma (13.88). Molecular analysis revealed 3 different SNP points in 5 samples (4006G>A, 3619A>G, and 3761C>T). The allelic variant 4006G>A (1/36) resulted in the alteration of the amino acid valine by isoleucine (V1336 I). The mutation 3619A>G (2/36) inserted the amino acid alanine instead of threonine (T1207 A). The mutation 3761C>T (2/36) led to the alteration of the amino acid serine by phenylalanine (S1254 F), a mutation for which there are no published reports. The histological types that showed BRCA1 mutations were complex carcinoma (1/5), carcinoma in mixed tumor (1/5), papillary carcinoma (1/5) and tubular carcinoma (2/5). Software analysis identified the new SNP (nucleotide 3761) in BRCA1 and 2 point mutations in nucleotides 4006 and 3619 and responsible for genetic instability. The development of breast cancer is caused by many endogenous and exogenous factors. The results of our study show that these factors have a greater presence in female, mixed breed, uncastrated, and older dogs, confirming the data in the veterinary literature. In the present study, we found different histological types of malignant breast tumors with mutations in the BRCA1 gene, as other authors have reported. However, we also found the mutation 3761C>T, which, to the best of our knowledge, has not been reported in the literature. This shows the need for studies in veterinary medicine that assess mutations in the BRCA1 gene and the most common histological types. In conclusion, SNPs in the BRCA1 gene cause genetic instability, resulting in additional mutations that lead to the development of breast tumors. They are point mutations that affect transcription, resulting in truncated proteins. These proteins may have a loss of function, leading to carcinogenesis.(AU)

Cáncer de mama en seis familias del Tolima y el Huila: mutación BRCA1 3450del4 / Breast cancer in six families from Tolima and Huila: BRCA1 3450del4 mutation

Introducción. El cáncer de mama es un problema mundial de salud pública; entre el 5 y el 10 % de los casos presentan agregación familiar, lo que se explicaría por la presencia de mutaciones en genes de alto riesgo como el BRCA1 y el BRCA2. El origen fundador de la deleción BRCA1 3450del4 en Colombia ya fue reportado. Objetivo. Hacer un análisis descriptivo de seis familias del del Tolima y del Huila con la deleción BRCA1 3450del4 de la asociación de la mutación germinal, con el cáncer de mama y la agregación familiar. Materiales y métodos. Se hizo un estudio descriptivo y transversal de seis casos índice con cáncer de mama positivos para BRCA1 3450del4, que cumplían tres de los criterios establecidos por Jalkh, et al. A partir de la información de las entrevistas, se realizaron los árboles genealógicos (GenoPro™, versión 2016). Se tipificó la mutación en familiares sanos y afectados que aceptaron participar. Resultados. De los 78 individuos seleccionados por conveniencia en las seis familias, 30 presentaron la mutación BRCA1 3450del4; de ellos, seis tenían cáncer de mama, uno, cáncer de ovario, uno, cáncer de mama y ovario, y otro, cáncer de próstata; 21 no presentaban neoplasias. De los 30 individuos portadores de la variante patogénica, seis eran hombres y 24 mujeres, 13 de ellas menores de 30 años. Conclusiones. En este estudio se confirmó la asociación de la deleción BRCA1 3450del4 con el cáncer de mama de agregación familiar.

Introduction: Breast cancer is a worldwide public health problem; between 5% and 10% of the cases present familial aggregation explained by genes of high risk such as BRCA1and BRCA2. The founding origin of the deletion BRCA1 3450del4 in Colombia has been previously reported. Objective: To carry out in six families from Tolima and Huila departments a descriptive analysis of the presence of the BRCA1 3450del4 mutation associated with breast cancer and familial aggregation. Materials and methods: We conducted a descriptive and cross-sectional study of six index cases with breast cancer positive for BRCA1 3450del4 that fulfilled three of the criteria established by Jalkh, et al. The genealogical trees were made using the information of the interview data (GenoPro™, version 2016). The mutation was typified in healthy and affected relatives who agreed to participate. Results: Thirty of the 78 individuals selected by convenience in the six families presented the mutation BRCA1 3450del4 six of whom developed breast cancer, one, ovarian cancer, one ovarian and breast cancer, and one prostate cancer; 21 did not present any type of neoplasm at the time of the study. Of the 30 individuals carrying the pathogenic variant, six were men, 24 were women, and 13 of these were under 30. Conclusions: In this study of families with the deletion BRCA1 3450del4 in Tolima and Huila we confirmed its association with familial aggregation of breast cancer.

Aspectos moleculares envolvidos no surgimento do Tumor Triplo-Negativo de Mama em pacientes portadoras ou não de mutação germinativa em BRCA1 / Molecular aspects involved in development of triple-negative breast cancer in patients with or without germline mutation in BRCA1

O Câncer de Mama Triplo-Negativo (CMTN), caracterizado pela perda de expressão dos receptores de estrógeno (RE), de progesterona (RP) e pela não super-expressão/amplificação do receptor do fator de crescimento epidermal humano do tipo 2 (HER-2), é considerado um subtipo bastante agressivo e heterogêneo molecularmente. Clinicamente, o CMTN apresenta prognóstico ruim, altas taxas de recorrência e menor sobrevida global em relação aos outros subtipos de câncer de mama. Ele corresponde a aproximadamente 15% dos casos de câncer de mama e não apresenta nenhuma terapia alvo efetiva. Mutação patogênica germinativa nos genes BRCA1 e BRCA2 leva a um aumento de risco para o desenvolvimento de Câncer de Mama e Ovário, sendo que mutação germinativa em BRCA1 está associada ao desenvolvimento de CMTN, especialmente em pacientes diagnosticadas antes dos 50 anos. A deficiência de BRCA1 leva ao mecanismo ineficiente do reparo do DNA e ao desenvolvimento do tumor. Recentemente, nosso grupo classificou as pacientes diagnosticadas com CMTN em grupo Hereditário (com mutação patogênica germinativa em BRCA1) e grupo Esporádico (sem mutação germinativa em BRCA1). Estes foram ainda classificados em tumores BRCA1-deficiente (com hipermetilação no promotor de BRCA1) e em tumores BRCA1-proficiente (sem hipermetilação no promotor de BRCA1 e sem mutação germinativa em BRCA1). As diferenças moleculares entre esses grupos de CMTN são de grande interesse clínico e biológico, embora ainda não sejam conhecidas. Dentro desse contexto, nosso objetivo foi investigar o perfil transcricional de CMTN sob diferentes aspectos de deficiência de BRCA1. Para isso, foi avaliado o sequenciamento do RNA (RNA-Seq) de 37 casos de CMTN em idade jovem (≤ 50 anos), sendo 9 casos Hereditário (com mutação patogênica germinativa em BRCA1) e 28 casos Esporádico. Dos casos Esporádicos, 9 foram BRCA1-deficiente (com o promotor de BRCA1 hipermetilado) e 19 BRCA1-proficiente (com o promotor de BRCA1 não hipermetilado). Utilizamos o RNA total a partir das 37 amostras tumorais e 25 amostras normais pareadas adjacentes ao tumor. As bibliotecas de cDNA foram construídas a partir do RNA total através do método de depleção do rRNA e sequenciadas na plataforma NextSeq (Illumina). Para a normalização dos dados de expressão de cada gene, foi aplicada a medida FPKM. Os critérios para a obtenção dos genes diferencialmente expressos (GDEs), nas amostras tumorais em relação às normais, foram fold change ≥ 4,0 e ≤ - 4,0 e p valor ajustado ≤ 0,05). Para classificação molecular dos tumores TN, foi utilizada a ferramenta online TNBCtype. As curvas de sobrevida global de acordo com essa classificação molecular foram calculadas através do método de Kaplan-Meier. Para verificar os processos biológicos envolvidos com a tumorigênese do CMTN, os GDEs foram submetidos a uma análise funcional in silico através do programa Ingenuity Pathway Analysis (IPA). Em média, 48.627.204 milhões de sequências foram geradas por amostra, das quais 79,5% foram mapeadas no genoma humano referência, revelando, em média, 15.071 genes expressos com pelo menos 10 sequências única mapeada por amostra. O perfil transcricional das amostras CMTN permitiu a classificação nos 7 subtipos moleculares de CMTN, sendo a maioria das amostras classificadas no subtipo imunomodulador (IM) e mesenquimal (M). No grupo das amostras BRCA1-deficiente, observamos um predomínio do subtipo IM enquanto que, nas amostras BRCA1-proficiente, houve um maior número de amostras classificadas em M. Não observamos diferença nas curvas de sobrevida global entre os dois grupos de amostras. Porém, os resultados mostraram que o subtipo IM parece ter uma tendência de melhor sobrevida global comparado com os outros subtipos, independente do status de BRCA1. A expressão diferencial das amostras tumorais em relação às amostras normais no grupo de CMTN Hereditário revelou 1965 GDEs, sendo 589 mais expressos e 1376 menos expressos no tumor; e, no grupo de CMTN Esporádico, a análise revelou 1837 GDEs, sendo 645 mais expressos e 1192 menos expressos no tumor. A partir dos GDEs de cada grupo, a análise do IPA mostrou que os dois grupos apresentaram vias canônicas enriquecidas comuns significantemente ativadas e envolvidas, de forma geral, com a Regulação do ciclo celular. Entretanto, as vias canônicas significantemente inibidas mostraram-se exclusivas em cada grupo: a via de Sinalização do receptor do glutamato foi a mais significativa (z-score = -2,12) nas amostras de CMTN Hereditário; e a via de Ativação de LXR/RXR foi a mais significativa (z-score = -2,98) nas amostras CMTN Esporádico. Além disso, observamos reguladores transcricionais significantemente ativados e inibidos exclusivamente em cada grupo. Os genes TNF e E2F1 foram os mais significantemente ativados apenas nas amostras de CMTN Hereditário (z-score = 4,06) e de CMTN Esporádico (z-score = 2,22), respectivamente. Por outro lado, o microRNA mir-21 e o gene PPARG foram os reguladores inibidos exclusivamente nas amostras CMTN Hereditário (-score = -4,68) e nas amostras CMTN Esporádico (z-score = -4,24), respectivamente. Esse estudo, de forma geral, revelou potenciais vias e genes reguladores de cascatas de sinalização envolvidos na tumorigênese do CMTN no contexto da deficiência de BRCA1, contribuindo na elucidação da complexidade funcional de tumores TN

Triple-negative breast cancer (TNBC), characterized by lack of expression of the estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2), results in aggressive biology, early peak of recurrence, and shorter overall survival than other subtypes. It comprises approximately 15% of breast cancer cases and yet there is no effective therapy. Mutations in the BRCA1 and BRCA2 genes are associated with increased risk of breast and ovarian cancers since germline mutation in BRCA1 is associated with the development of TNBC, especially in patients diagnosed before age 50. BRCA deficiency leads to impaired DNA repair and tumor development. Recently, our group classified TNBC patients into hereditary BRCA1-mutated and sporadic BRCA1-proficient. These were further classified into BRCA1-deficient tumors (with BRCA1 promotor hypermethylation) and BRCA1-proficient tumors (no BRCA1 promoter hypermethylation neither BRCA1 germline mutation). Molecular differences between hereditary and sporadic TNBC groups are clinically and biologically interesting although it remains unclear. In this context, we aimed to investigate the transcriptional profile of TNBC-associated or not with BRCA1 deficiency. For that, RNA sequencing (RNA-seq) from 37 early-onset TNBC (≤ 50 years old) was evaluated, comprising 9 Hereditary (with BRCA1 germline pathogenic mutation) and 28 Sporadic cases, of which 9 BRCA1-deficient and 19 BRCA1-proficient. Total RNA from 37 tumors samples and 25 adjacent normal samples of paired cases were used to constructed RNAseq libraries by depleting ribosomal RNA and sequenced on Illumina NextSeq 500 platform. Expression values were normalized by FPKM. Differentially expressed genes (DEGs) between tumor and normal samples were obtained using fold-change ≥ |4| and p value adjusted ≤ 0.05 as statistical criteria. The TNBC samples were subtyping using the web-based prediction tool TNBCType. Overall survival curves were calculated using the Kaplan.Meir method. IPA software was used to detect activated/inactivated canonical pathways and relevant upstream regulators, considering a z-score ≤-2.0 and ≥ 2.0, respectively. On average, 49 million reads were generated per sample, of which 79.5% were mapped to the human reference genome revealing 15,071 expressed genes with at least 10 reads per sample. From the transcriptional profile of TNBC samples we classified into seven TNBC subtypes being the majority of tumors classified as immunomodulatory (IM) and mesenchymal (M) subtype. We detected no difference in overall survival for both groups. However, trends towards better overall were observed for TNBC samples classified as IM compared with other subtypes, without associations with BRCA1 status. Differential gene expression analysis between tumor and normal samples in the hereditary group revealed 1,965 DEGs, being 589 upregulated and 1,376 downregulated; and in the sporadic group, the analysis revealed 1,837 DEGs, being 645 upregulated and 1,192 downregulated. Using the DEGs of each group, the IPA analysis revealed that Cell Cycle Regulation signaling was activated in both groups. Regarding inactivated pathways, we detected the Glutamate Receptor signaling (z-score = -2,12) in hereditary TNBC and the LXR/RXR activation in sporadic TNBC (z-score = -2,98). Also, the IPA analysis revealed relevant specific transcription regulators of each group. The TNF and E2F1 were the most significantly activated genes in hereditary- and sporadic-TNBC, respectively. On the other hand, the mir-21 and PPARG were the most significantly unique inhibited regulators in hereditary and sporadic, respectively. In general, this study unveiled potential pathways and regulatory genes for signaling cascades involved in TNBC tumorigenesis considering the deficiency of BRCA1, contributing to the elucidation of the functional complexity of the tumorigenic process of TNBC patients

Predisposição hereditária ao câncer de mama e sua relação com os genes BRCA1 e BRCA2: revisão da literatura / Hereditary predisposition to breast cancer and its relation to the BRCA1 and BRCA2 genes: literature review

O câncer de mama é o principal câncer que atinge a população feminina no mundo, com maior taxa de incidência e mortalidade, sendo que de 5% a 10% de todos os casos são relacionados à herança de mutações genéticas. A identificação precoce dos casos de câncer de mama e ovário é importante, pois um indivíduo afetado pode herdar propriedade de antecedentes familiares que indicam uma predisposição hereditária. O efeito cancerígeno pode ocorrer quando dois genes supressores de maior importância, como BRCA1 e BRCA2, perdem suas funções nos dois alelos decorrentes de mutações na linhagem germinativa. Desta forma, foi realizada uma revisão da literatura sobre câncer de mama hereditário e suas correlações com mutações germinativas nos genes BRCA1 e BRCA2 que aumentam o risco para o desenvolvimento de câncer de mama.

Costo efectividad de la cirugía reductora de riesgo en trompas y ovarios en casos con mutación del gen BRCAI en Colombia / Cost-effectiveness of risk-reducing salpingo-oophorectomy in cases of BRCA1 gene mutation in Colombia

RESUMEN Objetivo Evaluar la utilidad de la cirugía reductora de riesgo en trompas y ovarios en casos con mutación del gen BRCA1 en Colombia Material y Métodos Análisis de costo-efectividad en el que se incorporan tres procesos: a. Pacientes con pruebas de tamización para cáncer de mama y ovario. b. cirugía reductora de riesgo en trompas y ovarios c. cirugía reductora de riesgo en trompas y ovarios con mastectomía bilateral. Se evalúa como desenlace la ganancia en años de supervivencia. Resultados La cohorte con cirugía reductora de riesgo en trompas y ovarios y mastectomía bilateral es la de mayor ganancia con 13 años mientras que la cirugía reductora de riesgo en trompas y ovarios gana 4,95 años con respecto al grupo de seguimiento. Conclusiones Las tres opciones evaluadas son aceptables, pero de ellas la de mayor ganancia en la supervivencia es la combinación de cirugía reductora de riesgo en trompas y ovarios con mastectomía bilateral.(AU)

ABSTRACT Objective To assess the usefulness of risk reduction salpingo-oophorectomy in cases with mutation of the BRCA1 gene in Colombia. Material and Methods Cost-effectiveness analysis in which three processes are incorporated: a. Patients with screening tests for breast and ovarian cancer. b. Risk reduction surgery in the fallopian tubes and ovaries c. Reductive surgery in the fallopian tubes and ovaries with bilateral mastectomy. The outcome is evaluated as the gain in years of survival. Results The cohort with risk reduction surgery in the fallopian tubes and ovaries and bilateral mastectomy is the one with the highest gain with 13 years, while the risk reduction surgery in the fallopian tubes and ovaries gain 4.95 years with respect to the follow-up group. Conclusions The three options evaluated are acceptable, but of them the one with the greatest gain in survival is the combination of risk-reducing surgery in the fallopian tubes and ovaries with bilateral mastectomy.(AU)

Downregulation of TGF-ß1 suppressed proliferation and increased chemosensitivity of ovarian cancer cells by promoting BRCA1/Smad3 signaling

BACKGROUND: Studies have demonstrated that transforming growth factor beta-1 (TGF-ß1) exhibits oncogenic activity in different types of cancer, including ovarian cancer (OC). However, its regulatory mechanism in OC and whether TGF-ß1 is involved in chemosensitivity regulation remains unclear. Thus, the aim of this study was to investigate the role of TGF-ß1 in OC. METHODS: The OC cell line SKOV3 was employed, and TGF-ß1 overexpression or knockdown vectors were constructed. The cell proliferation of SKOV3 was evaluated with the cell counting kit (CCK8) kit after treatment with different concentrations of cis-platinum. Western blot and protein immunoprecipitation were employed to detect changes in BRCA1 and Smad3 expression and their interactions. Tumor growth in nude mice was evaluated. RESULTS: The results showed that TGF-ß1 knockdown increased chemosensitivity by promoting BRCA1 expression and Smad3 phosphorylation. In vivo studies showed that TGF-ß1 knockdown significantly inhibited the growth of tumors, also by upregulating BRCA1 expression and Smad3 phosphorylation. CONCLUSION: Taken together, our results suggest that TGF-ß1 knockdown inhibits tumor growth and increases chemosensitivity by promotion of BRCA1/Smad3 signaling.

Cost effectiveness of the cancer prevention program for carriers of the BRCA1/2 mutation

ABSTRACT OBJECTIVE: To analyze the cost effectiveness of the diagnostic program for the germline mutation in BRCA1/2 genes and of preventative strategies for the relatives of patients diagnosed with ovarian cancer associated with this mutation. METHODS: The study analyzed the cost effectiveness by developing an analysis of the Markov decision process from the perspective of the National Health System. The strategies compared reflect upon the adoption of genetic testing and preventative strategies for relatives or the usual care currently proposed. The incremental cost-effectiveness ratio was expressed in terms of cost per case avoided. The sensitivity analysis was performed in a univariate and deterministic manner. RESULTS: The study showed increments for effectiveness and for costs when performing genetic testing and adopting prophylactic measures for family members. The incremental cost-effectiveness ratio was estimated at R$908.58 per case of cancer avoided, a figure considered lower than the study's cost-effectiveness threshold (R$7,543.50). CONCLUSIONS: The program analyzed should be considered a cost-effective strategy for the national situation. Studies in various other countries have reached similar conclusions. One possible ramification of this research might the need to perform a budgetary-impact analysis of making the program one of the country's health policies.

Cáncer de mama y ovario hereditario en Uruguay: resultados del screening para mutaciones en genes de susceptibilidad por secuenciación de nueva generación / Hereditary breast and ovary cancer in Uruguay: screening results for mutations in susceptibility genes by new generation sequencing

Introducción: el cáncer de mama representa la primera causa de muerte por cáncer en mujeres de Uruguay. Se estima que cerca de 7% son causados por mutaciones en el ácido desoxirribonucleico germinal. Los costos de la secuenciación genética han descendido dramáticamente gracias a la aparición de la secuenciación de nueva generación (NGS). El cambio tecnológico abrió una nueva etapa en el estudio del cáncer hereditario en nuestro país. Objetivo: comunicar los resultados de la utilización de tecnología NGS y paneles multigénicos en familias uruguayas con alto riesgo de cáncer de mama hereditario. Pacientes y método: se secuenciaron 135 familias de alto riesgo que provenían de la consulta de consejería genética que funciona en el Grupo Colaborativo Uruguayo: Investigación de afecciones oncológicas hereditarias. Cuando la historia familiar sugería claramente un síndrome de cáncer de mama y ovario hereditario se efectuó secuenciación NGS exclusiva de los genes BRCA1 y 2; cuando el patrón familiar no configuraba claramente se utilizó un panel multigénico. Resultados: se efectuó NGS exclusiva de genes BRCA1 y 2 en 62 familias y un panel multigénico en 73 familias. Se identificaron en total 29 mutaciones patógenas (21 en genes BRCA y 8 en otros genes). Dos de ellas fueron noveles y tres pueden considerarse recurrentes en la población uruguaya. Conclusiones: este trabajo es el primero en Uruguay en reportar el resultado de esta nueva tecnología en el cáncer de mama hereditario. El hallazgo de 29 mutaciones patógenas nos ayuda a delinear el perfil mutacional de nuestro país.

Introduction: breast cancer is women's first cause of death in Uruguay. According to estimations, around 7% of cases result from germinal mutations by deoxyribonucleic acid. The cost of genetic sequencing has dramatically dropped thanks to the arrival of next-generation sequencing (NGS). This technological change opened a new era in the study of hereditary cancer in our country. Objective:to communicate the results of using NGS technology and multigenic panels in Uruguayan families with high risk of hereditary breast cancer. Method: 135 high risk families referred by the genetic counselling consultation that is provided at the Uruguayan Collaborative Group (Hereditary Oncological Conditions Research) were sequenced. When the family history clearly suggested hereditary breast and ovary cancer was a possibility, exclusive NGS sequencing was done for BRCA1 and BRCA2 genes; when the family pattern was not clear to this respect, multigenic panels were used. Results: exclusive NGS sequencing for BRCA1 and BRCA2 genes was done in 62 families, and multigenic panels were used in 73 families. 29 pathogenic mutations were identified (21 in BRCA genes and 8 in other genes). Two of them were new to the disease and three could be considered recurrent in the Uruguayan population. Conclusions:this study is the first one in Uruguay to report the results of this new technology in hereditary breast cancer. The finding of 29 pathogenic mutations contributes to outlining the mutational profile of our country.

Introdução: o câncer de mama é a primeira causa de morte por câncer em mulheres no Uruguai. Estima-se que aproximadamente 7% sejam causados por mutações no ácido desoxirribonucleico germinal. Os custos da sequenciação genética diminuíram dramaticamente graças ao aparecimento da sequenciação de nova geração (NGS). Esta nova tecnologia deu inicio a uma nueva etapa no estudo do câncer hereditário no nosso país. Objetivo: comunicar os resultados da utilização de tecnologia NGS e painéis mutagênicos em famílias uruguaias com alto risco de câncer de mama hereditário. Pacientes e método: 135 famílias de alto risco originárias do aconselhamento genético que funciona no Grupo Colaborativo Uruguaio: Pesquisa de afecções oncológicas hereditárias foram sequenciadas. Quando a história familiar sugeria uma síndrome de câncer de mama e ovário hereditários fez-se a secuenciacao NGS exclusivamente dos genes BRCA1 e 2; quando o padrão familiar não era claro foi utilizado um painel multigênico. Resultados: realizou-se NGS exclusivamente de genes BRCA1 e 2 em 62 famílias e um painel multigênico em 73 famílias. Foram identificadas 29 mutações patogênicas (21 em genes BRCA e 8 em outros genes). Duas eram novas e três podem ser consideradas como recorrentes na população uruguaia. Conclusões: este trabalho é o primeiro que apresenta os resultados desta nova tecnologia aplicada ao câncer de mama hereditário no Uruguai. O achado de 29 mutações patogênicas ajuda a definir o perfil mutacional do nosso país.

Mutations in BRCA1, BRCA2 and other breast and ovarian cancer susceptibility genes in Central and South American populations

Breast cancer (BC) is the most common malignancy among women worldwide. A major advance in the understanding of the genetic etiology of BC was the discovery of BRCA1 and BRCA2 (BRCA1/2) genes, which are considered high-penetrance BC genes. In non-carriers of BRCA1/2 mutations, disease susceptibility may be explained of a small number of mutations in BRCA1/2 and a much higher proportion of mutations in ethnicity-specific moderate- and/or low-penetrance genes. In Central and South American populations, studied have focused on analyzing the distribution and prevalence of BRCA1/2 mutations and other susceptibility genes that are scarce in Latin America as compared to North America, Europe, Australia, and Israel. Thus, the aim of this review is to present the current state of knowledge regarding pathogenic BRCA variants and other BC susceptibility genes. We conducted a comprehensive review of 47 studies from 12 countries in Central and South America published between 2002 and 2017 reporting the prevalence and/or spectrum of mutations and pathogenic variants in BRCA1/2 and other BC susceptibility genes. The studies on BRCA1/2 mutations screened a total of 5956 individuals, and studies on susceptibility genes analyzed a combined sample size of 11,578 individuals. To date, a total of 190 different BRCA1/2 pathogenic mutations in Central and South American populations have been reported in the literature. Pathogenic mutations or variants that increase BC risk have been reported in the following genes or genomic regions: ATM, BARD1, CHECK2, FGFR2, GSTM1, MAP3K1, MTHFR, PALB2, RAD51, TOX3, TP53, XRCC1, and 2q35.

Síndrome de cáncer hereditario de mama y ovario: aplicación clínica / Hereditary breast and ovarian cancer syndrome: Clinical application

Aportar al ginecólogo herramientas para la identificación de pacientes con riesgo de síndrome de cáncer hereditario de mama y ovario (SCHMO), y brindar consejería en el manejo preventivo de pacientes con este síndrome.Materiales y métodos: a partir de un caso hipotético se formulan preguntas relacionadas con el riesgo de desarrollar cáncer de mama y ovario en pacientes con SCHMO. Para responder estas preguntas se realizó una revisión de la literatura pertinente en las bases de datos Medline vía PubMed, ScienceDirect y SciELO. Se utilizaron los términos MESH "Síndrome de cáncer de mama y ovario hereditario", "Neoplasias ováricas", "Neoplasias de la mama", "Genes BRCA1", "Genes BRCA2" y su equivalente en inglés. Los resultados se restringieron a artículos publicados entre el 2005 y 2015.Resultados: a través de la búsqueda en PubMed se obtuvieron 56 artículos, de los cuales se seleccionaron 45. En ScienceDirect y SciELO se encontraron 7 artículos. Además, se incluyeron 4 artículos de fuentes no ligadas a estas bases de datos.Conclusiones: el ginecoobstetra debe identificar pacientes con riesgo de presentar el síndrome de cáncer hereditario de mama y ovario, y explicar a los pacientes la importancia de la realización de las pruebas moleculares de los genes BRCA1 y BRCA2 y de participar en equipos multidisciplinarios que además deben incluir al genetista, cirujano, los oncólogos y al paciente para la toma de decisiones médicas de acuerdo con los resultados moleculares...

To provide gynaecologists with tools for the identification of patients at risk of hereditary breast and ovarian cancer syndrome (HBOC) and present advise regarding the preventive management of patients with this syndrome.Materials and methods: Questions were asked in relation to the risk of patients with HBOC developing breast and ovarian cancer. To answer those questions, a review of the relevant literature was conducted in the Medline database via PubMed, and in ScienceDirect and SciELO. The MESH terms used were Breast and Ovarian Cancer Syndrome, Ovarian Neoplasms, Breast Neoplasms, BRCA1 Genes, BRCA2 Genes, and their equivalent in English. Results were limited to articles published between 2005 and 2015.Results: Overall, 56 articles were found in PubMed, of which 45 were selected. The search in ScienceDirect and SciELO resulted in 7 articles. Additionally, 4 articles from other sources not linked to these data bases were also included.Conclusions: Obstetric gynaecologists must identify patients at risk of presenting Hereditary Breast and Ovarian Cancer Syndrome, and explain to the patients the importance of performing molecular testing for BRCA1 and BRCA2 genes; and they must participate in multi-disciplinary teams consisting also of geneticists, surgeons, oncologists and patients for medical decision-making in accordance with the molecular results...

Pesquisa e propriedade intelectual envolvendo material humano: afinal,de quem são nossos genes? / /Research and intellectual property involving human material: after all,from whom are our genes? / /La investigación y la propiedad intelectual implicando material humano:¿al final, a quien pertenecen nuestros genes?

O presente artigo discute aspectos éticos, científicos e jurídicos sobre o patenteamento de genes humanos,partindo de um contexto histórico sobre propriedade intelectual de seres vivos e passando pela decisão da Suprema Corte dos EUA relativa ao caso Myriad Genetics, conflito em torno da patente dos genes BRCA1e BRCA2, relacionados ao câncer de mama e de ovário. Além disso, o artigo aborda diplomas normativos sobre o assunto, considerando tanto a legislação brasileira quanto a internacional. Por fim, contrapõe posições distintas sobre patente de genes humanos, adotando posicionamento crítico que o assunto merece...

This article discusses ethical, scientific and legal aspects of the patenting of human genes, startingfrom a historical context of intellectual property of living beings and passing through the decision ofthe US Supreme Court in Myriad Genetics case, conflict over patent of the genes BRCA1 and BRCA2,related to breast cancer and ovarian cancer. Moreover, the article discusses regulatory instrumentson the subject, considering both the Brazilian and international legislation. Finally, it contrastsdifferent positions on patent of human genes, adopting critical position that this matter deserves...

Este artículo aborda los aspectos éticos, científicos y legales de las patentes de genes humanos, a partir de uncontexto histórico de la propiedad intelectual de los seres vivos y pasando por la decisión de la Corte Suprema deEstados Unidos en el caso Myriad Genetics, el conflicto sobre patentes de los genes BRCA1 y BRCA2 relacionadoscon el cáncer de mama y cáncer de ovario. Además, el artículo analiza los instrumentos normativos sobre eltema, teniendo en cuenta tanto la legislación brasileña como internacional. Por último, contrasta diferentesposiciones sobre las patentes de los genes humanos, y adopta una posición crítica que este asunto merece...