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Braz. j. biol ; 84: e255235, 2024. tab, graf
Article in English | MEDLINE, LILACS, VETINDEX | ID: biblio-1355897


Abstract In soybean breeding program, continuous selection pressure on traits response to yield created a genetic bottleneck for improvements of soybean through hybridization breeding technique. Therefore an initiative was taken to developed high yielding soybean variety applying mutation breeding techniques at Plant Breeding Division, Bangladesh Institute of Nuclear Agriculture (BINA), Bangladesh. Locally available popular cultivar BARI Soybean-5 was used as a parent material and subjected to five different doses of Gamma ray using Co60. In respect to seed yield and yield attributing characters, twelve true breed mutants were selected from M4 generation. High values of heritability and genetic advance with high genotypic coefficient of variance (GCV) for plant height, branch number and pod number were considered as favorable attributes for soybean improvement that ensure expected yield. The mutant SBM-18 obtained from 250Gy provided stable yield performance at diversified environments. It provided maximum seed yield of 3056 kg ha-1 with highest number of pods plant-1 (56). The National Seed Board of Bangladesh (NSB) eventually approved SBM-18 and registered it as a new soybean variety named 'Binasoybean-5' for large-scale planting because of its superior stability in various agro-ecological zones and consistent yield performance.

Resumo No programa de melhoramento da soja, a pressão pela seleção contínua para a resposta das características de rendimento criou um gargalo genético para melhorias da soja por meio da técnica de melhoramento por hibridação. Portanto, foi desenvolvida uma variedade de soja de alto rendimento, aplicando técnicas de reprodução por mutação, na Divisão de Melhoramento de Plantas, no Instituto de Agricultura Nuclear de Bangladesh (BINA), em Bangladesh. A cultivar popular BARI Soybean-5, disponível localmente, foi usada como material original e submetida a cinco doses diferentes de raios gama usando Co60. Em relação ao rendimento de sementes e às características de atribuição de rendimento, 12 mutantes genuínos foram selecionados a partir da geração M4. Altos valores de herdabilidade e avanço genético com alto coeficiente de variância genotípico (GCV) para altura da planta, número de ramos e número de vagens foram considerados atributos favoráveis ​​ao melhoramento da soja, garantindo, assim, a produtividade esperada. O mutante SBM-18, obtido a partir de 250Gy, proporcionou desempenho de rendimento estável em ambientes diversificados e produtividade máxima de sementes de 3.056 kg ha-1 com o maior número de vagens planta-1 (56). O Conselho Nacional de Sementes de Bangladesh (NSB) finalmente aprovou o SBM-18 e o registrou como uma nova variedade de soja, chamada 'Binasoybean-5', para plantio em larga escala por causa de sua estabilidade superior em várias zonas agroecológicas e desempenho de rendimento consistente.

Soybeans/growth & development , Soybeans/genetics , Phenotype , Bangladesh , Plant Breeding , Genotype , Mutation
Braz. j. biol ; 83: e246040, 2023. tab, graf
Article in English | MEDLINE, LILACS, VETINDEX | ID: biblio-1285610


Abstract Autosomal recessive primary microcephaly (MCPH) is a neurodevelopmental disorder characterized by a congenitally reduced head circumference (-3 to -5 SD) and non-progressive intellectual disability. The objective of the study was to evaluate pathogenic mutations in the ASPM gene to understand etiology and molecular mechanism of primary microcephaly. Blood samples were collected from various families across different remote areas of Pakistan from February 2017 to May 2019 who were identified to be affected with primary microcephaly. DNA extraction was performed using the salting-out method; the quality and quantity of DNA were evaluated using spectrophotometry and 1% agarose gel electrophoresis, respectively in University of the Punjab. Mutation analysis was performed by whole exome sequencing from the Cologne Center for Genomics, University of Cologne. Sanger sequencing was done in University of the Punjab to confirm the pathogenic nature of mutation. A novel 4-bp deletion mutation c.3877_3880delGAGA was detected in exon 17 of the ASPM gene in two primary microcephaly affected families (A and B), which resulted in a frame shift mutation in the gene followed by truncated protein synthesis (p.Glu1293Lysfs*10), as well as the loss of the calmodulin-binding IQ domain and the Armadillo-like domain in the ASPM protein. Using the in-silico tools Mutation Taster, PROVEAN, and PolyPhen, the pathogenic effect of this novel mutation was tested; it was predicted to be "disease causing," with high pathogenicity scores. One previously reported mutation in exon 24 (c.9730C>T) of the ASPM gene resulting in protein truncation (p.Arg3244*) was also observed in family C. Mutations in the ASPM gene are the most common cause of MCPH in most cases. Therefore, enrolling additional affected families from remote areas of Pakistan would help in identifying or mapping novel mutations in the ASPM gene of primary microcephaly.

Resumo Microcefalia primária autossômica recessiva (MCPH) é um distúrbio do neurodesenvolvimento caracterizado por uma redução congênita do perímetro cefálico (-3 a -5 DP) e deficiência intelectual não progressiva. O objetivo do estudo foi avaliar mutações patogênicas no gene ASPM a fim de compreender a etiologia e o mecanismo molecular da microcefalia primária. Amostras de sangue foram coletadas de várias famílias em diferentes áreas remotas do Paquistão de fevereiro de 2017 a maio de 2019, que foram identificadas como afetadas com microcefalia primária. A extração do DNA foi realizada pelo método salting-out; a qualidade e a quantidade de DNA foram avaliadas por espectrofotometria e eletroforese em gel de agarose a 1%, respectivamente, na Universidade de Punjab. A análise de mutação foi realizada por sequenciamento completo do exoma do Cologne Center for Genomics, University of Cologne. O sequenciamento de Sanger foi feito na Universidade do Punjab para confirmar a natureza patogênica da mutação. Uma nova mutação de deleção de 4 bp c.3877_3880delGAGA foi detectada no exon 17 do gene ASPM em duas famílias afetadas por microcefalia primária (A e B), que resultou em uma mutação de frame shift no gene seguida por síntese de proteína truncada (pGlu1293Lysfs * 10), bem como a perda do domínio IQ de ligação à calmodulina e o domínio do tipo Armadillo na proteína ASPM. Usando as ferramentas in-silico Mutation Taster, PROVEAN e PolyPhen, o efeito patogênico dessa nova mutação foi testado; foi previsto ser "causador de doenças", com altos escores de patogenicidade. Uma mutação relatada anteriormente no exon 24 (c.9730C > T) do gene ASPM, resultando em truncamento de proteína (p.Arg3244 *) também foi observada na família C. Mutações no gene ASPM são a causa mais comum de MCPH na maioria dos casos . Portanto, a inscrição de famílias afetadas adicionais de áreas remotas do Paquistão ajudaria a identificar ou mapear novas mutações no gene ASPM da microcefalia primária.

Humans , Microcephaly/genetics , Nerve Tissue Proteins/genetics , Pakistan , Consanguinity , Mutation/genetics
Acta Pharmaceutica Sinica ; (12): 271-276, 2022.
Article in Chinese | WPRIM | ID: wpr-922923


KRAS is one of the most frequently mutated human oncogenes. In spite of mounting efforts on the development of direct or indirect inhibition targeting KRAS, little has been achieved because of insurmountable difficulties, titling KRAS "undruggable". Recently, subtype-specific inhibitors have shown great hope. Some KRASG12C inhibitors have entered clinical trials, including adagrasib and sotorasib, and have shown preliminary clinical effectiveness. Experiences from the inhibitors targeting the downstream factors of RAS pathways show that the anticancer activity of these drugs will be limited due to the development of drug resistance. Preclinical studies of KRASG12C inhibitors have revealed that the application of these agents might be hampered by the drug resistance issue. The current review aims to describe the current status of KRASG12C inhibitors, and discuss the mechanisms underlying KRASG12C inhibitor resistance, so as to provide the clues for the combat of drug resistance.

Journal of Clinical Hepatology ; (12): 409-414, 2022.
Article in Chinese | WPRIM | ID: wpr-920895


Objective To investigate the gene mutations of Chinese patients with pancreatic cancer in the coastal regions of Eastern China, and to provide a basis for individualized treatment. Methods A total of 40 patients who were admitted and diagnosed with malignant pancreatic tumor after surgical treatment in The Affiliated Hospital of Qingdao University, Qingdao Municipal Hospital, Yantaishan Hospital, and Yantai Sino-France Friendship Hospital from January 2017 to June 2019 were enrolled. Next-generation sequencing (NGS) was used to detect gene mutations in tumor tissue and somatic cells, and the map of gene mutations was plotted to analyze genomic alterations. The chi-square test or the Fisher's exact test was used for comparison of categorical data between groups. The Kaplan-Meier method was used to plot survival curves, and the log-rank test was used for comparison between groups. Results Among the 40 patients, 34 (85.0%) had pancreatic ductal adenocarcinoma, 3 (7.5%) had solid pseudopapillary neoplasm of the pancreas, 1 (2.5%) had pancreatic neuroendocrine tumor, and 2 (5.0%) had unclear typing. KRAS (80.0%, 32/40), TP53 (70.0%, 28/40), CDKN2A (32.5%, 13/40), SMAD4 (17.5%, 7/40), and AKT2 (17.5%, 7/40) were the most common mutations, and there was no significant difference in survival time between the patients with these five common gene mutations (all P > 0.05). Conclusion NGS technology can provide comprehensive and accurate information of genomic alterations and may provide novel potential biomarkers for the diagnosis and precise treatment of pancreatic cancer. The analysis of mutant genes also lays a foundation for the individualized treatment of pancreatic cancer.

Einstein (Säo Paulo) ; 20: eAO6450, 2022. tab, graf
Article in English | LILACS | ID: biblio-1364794


ABSTRACT Objective To understand the feasibility of FGFR3 tests in the Brazilian public health context, and to sample the mutational burden of this receptor in high-grade muscle invasive bladder cancer. Methods A total of 31 patients with high-grade muscle-invasive bladder cancer were included in the present study. Either transurethral resection of bladder tumor or radical cystectomy specimens were analyzed. Formalin-fixed paraffin-embedded tissue blocks were sectioned, hematoxylin and eosin stained, and histologic sections were reviewed. Total RNA was extracted using the RNeasy DSP formalin-fixed paraffin-embedded kit. Qualitative results were displayed in Rotor-Gene AssayManager software. Results Six patients were excluded. From the samples analyzed, four (16.7%) were considered inadequate and could not have their RNA extracted. Two patients presented FGFR3 mutations, accounting for 9.5% of material available for adequate analysis. The two mutations detected included a Y373C mutation in a male patient and a S249C mutation in a female patient. Conclusion FGFR3 mutations could be analyzed in 84% of our cohort and occurred in 9.5% of patients with high-grade muscle invasive bladder cancer in this Brazilian population. FGFR3 gene mutations are targets for therapeutic drugs in muscle-invasive bladder cancer. For this reason, know the frequency of these mutations can have a significant impact on public health policies and costs provisioning.

Urinary Bladder Neoplasms/genetics , Carcinoma, Transitional Cell/genetics , Carcinoma, Transitional Cell/metabolism , Carcinoma, Transitional Cell/pathology , Receptor, Fibroblast Growth Factor, Type 3/genetics , Receptor, Fibroblast Growth Factor, Type 3/metabolism , Brazil , RNA , Prevalence , Eosine Yellowish-(YS) , Hematoxylin , Muscles/metabolism , Muscles/pathology , Mutation
An. Fac. Cienc. Méd. (Asunción) ; 54(3): 33-40, Dec. 2021.
Article in Spanish | LILACS | ID: biblio-1352903


El estado mutacional del KRAS ha sido considerado como biomarcador para tratamientos biológicos tras varios ensayos clínicos realizados en pacientes con cáncer colorrectal metastásico. Reportes recientes indican que las frecuencias de mutación del gen KRAS en pacientes con CCR de Asia, Europa y Latinoamérica están entre el 24%, 36% y 40%, respectivamente. Paraguay no cuenta con este tipo de informes, a pesar de registrar anualmente en promedio 75 nuevos casos de pacientes diagnosticados con CCR sólo en el Servicio de Cirugía General del Hospital Central del Instituto de Previsión Social (IPS). El presente trabajo ha implementado este análisis de rutina, prerrequisito obligatorio para la administración de fármacos basados en anticuerpos terapéuticos, y revelado una frecuencia de mutación del gen KRAS del 34% en pacientes paraguayos con CCR que acuden a los Servicios del Hospital Central del IPS

The mutational status of the KRAS has been consider as a biomarker for biological treatments after several clinical trials carried out in patient with metastatic colorectal cancer. Recent reports indicate that the KRAS gene mutation frequencies in CRC patients from Asia, Europe, and Latin America are between 24%, 36%, and 40%, respectively. Paraguay does not have this kind of reports, despite registering an average of 75 new cases of patients diagnosed with CRC per year only in the General Surgery Service of the "Central Hospital - Instituto de Prevision Social (IPS)". The present work has implemented this routine analysis, a mandatory prerequisite for the administration of drugs based on therapeutic antibodies and revealed a KRAS gene mutation frequency of 34% in Paraguayan patients with CRC who attend the IPS Central Hospital Services

Colorectal Neoplasms , Mutation , Cross-Sectional Studies , Determination , Genes
Medisan ; 25(6)2021. ilus
Article in Spanish | LILACS, CUMED | ID: biblio-1356477


El SARS-CoV-2, agente causal de la actual pandemia de la COVID-19, va sufriendo mutaciones como consecuencia de su ciclo evolutivo, lo que ha originado diferentes variantes genéticas, que han sido agrupadas en dos categorías: preocupante (alfa o británica, beta o sudafricana, gamma o brasileña y delta o india) y de interés (lamdba, mu, épsilon, eta, iota, kappa, zeta, theta); estas conllevan implicaciones clínicas en la transmisibilidad, virulencia y resistencia del SARS-CoV-2 a la inmunidad natural y adquirida, lo que representa un serio desafío para los servicios de salud en todo el mundo. En este artículo se describen dichas variantes genéticas, con énfasis en su probable impacto clínico, y además se plantea la posibilidad de que aparezcan otras, como fenómeno natural en la evolución de los virus.

The SARS-CoV-2, causal agent of the COVID-19 current pandemic, is suffering mutations as a consequence of its evolutive cycle, what has originated different genetic variants that have been grouped in two categories: worrying (alpha or British, beta or South African, gamma or Brazilian and delta or Indian) and of interest (lamdba, mu, epsilon, eta, iota, kappa, zed, theta); these categories bear clinical implications in the transmissibility, virulence and resistance from SARS-CoV-2 to the natural and acquired immunity, what represents a serious challenge in health services worldwide. These genetic variants are described in this work, with emphasis in its probable clinical impact, and the possibility that other variants could appear is also explained, as natural phenomenon in the evolution of viruses.

Coronavirus , SARS-CoV-2/genetics , COVID-19 , Drug Resistance, Viral , Mutation
Rev. peru. med. exp. salud publica ; 38(4): 577-586, oct.-dic. 2021. tab, graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1365926


RESUMEN Objetivo. Determinar la estructura genética de las cepas drogorresistentes de Mycobacterium tuberculosis que circularon en todo el Perú durante los años 2011-2015 a través de haplotipos obtenidos de un ensayo con sondas en línea. Materiales y métodos. Se analizaron 6589 muestras que ingresaron al Instituto Nacional de Salud para el diagnóstico rutinario mediante el ensayo GenoType® MTBDRplus v2, durante el periodo de estudio. Se crearon haplotipos resistentes mediante la concatenación de 21 sitios polimórficos de los genes evaluados por el ensayo con sondas en línea, y se realizó el análisis de asociación con fenotipos obtenidos por el método de proporciones agar 7H10. Resultados. Las mutaciones de mayores frecuencias fueron: rpoB S531L (55,4%) y rpoB D516V (18,5%) para la resistencia a rifampicina, y katG S315T (59,5%) e inhA c-15t (25,7%) para la resistencia a isoniacida. Se obtuvieron 13 haplotipos representativos (87,8% de muestras analizadas) de los cuales seis correspondieron al genotipo multidrogorresistente, cuatro al genotipo monorresistente a isoniacida y tres al genotipo monorresistente a rifampicina. Dieciocho departamentos, y la provincia del Callao, presentaron una alta diversidad haplotípica; cuatro presentaron moderada diversidad y dos presentaron baja diversidad. Conclusiones. Existe una alta diversidad haplotípica en la mayoría de los departamentos, además de una concentración de las cepas de Mycobacterium tuberculosis drogorresistentes en las ciudades de Lima y Callao. Asimismo, las cepas de Mycobacterium tuberculosis con perfil drogorresistente que circulan en el Perú contienen principalmente los marcadores genéticos de mayor prevalencia a nivel mundial asociados con la resistencia frente a rifampicina e isoniacida.

ABSTRACT Objective. To determine the genetic structure of drug-resistant strains of Mycobacterium tuberculosis that circulated throughout Peru during the years 2011-2015, by using haplotypes obtained from a line probe assay. Materials and methods. A total of 6589 samples that were admitted to the Instituto Nacional de Salud for routine diagnosis using the GenoType® MTBDRplus v2 assay were analyzed during the study period. Resistant haplotypes were created by concatenating 21 polymorphic sites of the evaluated genes using the line probe assay; and the association analysis was carried out with phenotypes obtained by the 7H10 agar ratio method. Results. The most frequent mutations were: rpoB S531L (55.4%) and rpoB D516V (18.5%) for rifampicin resistance, and katG S315T (59.5%) and inhA c-15t (25.7%) for isoniazid resistance. We obtained 13 representative haplotypes (87.8% of analyzed samples), 6 corresponded to the multidrug-resistant genotype, 4 to the isoniazid mono-resistant genotype and 3 to the rifampicin mono-resistant genotype. Eighteen regions and the province of Callao showed high haplotype diversity; four showed moderate diversity and two showed low diversity. Conclusions. Most regions showed high haplotype diversity; in addition, most drug-resistant strains of Mycobacterium tuberculosis were concentrated in the cities of Lima and Callao. Likewise, drug-resistant Mycobacterium tuberculosis strains circulating in Peru mainly contain the genetic markers with the highest prevalence worldwide, which are associated with resistance to rifampicin and isoniazid.

Rev. bras. neurol ; 57(3): 16-23, jul.-set. 2021. ilus
Article in English | LILACS | ID: biblio-1342511


Amyloidosis are characterized by mutations in the gene coding for transthyretin (TTR), located on chromosome 18. TTR is a set of four 127-aminoacid polypeptides structured as homotetrameric protein of 56 kDa with a secondary ß sheet structure. It plays the role of thyroxin (T4) carrier, and has a binding domain for retinol (vitamin A). It is synthesized in the liver, although a small quantity is also produced by the choroid plexus, and retinal cells. Mutations of this gene result in loss of tetramer stability. Insoluble amyloid fibrils (AF) are formed and deposited in tissues and organs. The abnormal aggregation of TTR protein trigger several syndromes, such as familial amyloid polyneuropathy (FAP-TTR), cardiomyopathies (CMP), and senile systemic amyloidosis (SSA). It is estimated there are 5,000 to 10,000 cases of FAP-TTR globally. OBJECTIVE: The study intends to develop an online platform for the diagnosis of FAP-TTR. The aim is to facilitate the diagnosis process and promote a tool for epidemiological study. METHODS: The project was based on a literature review featuring clinical and epidemiological evidence for the development of a practical platform (applied research). RESULTS: It was elaborated a platform containing a questionnaire to allow a more dynamic, cheaper, and efficient operation, mediated by a better characterization of the disease to enable its early diagnosis. CONCLUSION: The platform might become a valuable resource for the characterization, diagnosis, and future epidemiological study of FAP-TTR

As amiloidoses se caracterizam por mutações no gene codificante da transtirretina (TTR) no cromossomo 18. A proteína TTR compõe-se de uma corrente de polipeptídios de 127 resíduos, que constituem uma proteína homotetramérica de 56kDa com estrutura secundária de folha ß, que serve como proteína de deslocamento para a tiroxina (T4), e uma proteína de ligação ao retinol (vitamina A). O principal local de produção dessa proteína é o fígado, embora uma pequena quantidade seja produzida pelo plexo coroide e pelas células retinianas. O gene codificante da TTR (18q11.2-12) é pequeno (7 kb) e contém quatro éxons. As mutações convertem-se em perda do equilíbrio do tetrâmero proteico. Surgem assim, fibrilas amiloides (FA) em cadeias não ramificadas de 10 a 12 nm de diâmetro e fibrilas indissolúveis, que se condensam nos tecidos e órgãos. As síndromes concernentes ao acúmulo da proteína TTR são: polineuropatia amiloidótica familiar (PAFTTR), miocardiopatias (MCP) e amiloidose sistêmica senil (ASS). Estimativa recente relatou a existência de 5.000 a 10.000 casos de PAFTTR no mundo. OBJETIVO: O estudo objetiva elaborar uma plataforma de diagnóstico PAFTTR on-line para auxiliar como ferramenta de contribuição para o estudo da epidemiologia e facilitar o diagnóstico. MÉTODOS: O projeto baseou-se em uma pesquisa bibliográfica capaz de levantar evidências clínicas e epidemiológicas na elaboração de uma plataforma facilitadora (pesquisa aplicada). RESULTADOS: O resultado alcançado foi a elaboração da plataforma contendo um questionário, que tornará o trabalho dos profissionais mais dinâmico, barato e eficiente, caracterizando melhor a doença e promovendo um diagnóstico precoce. CONCLUSÃO: A plataforma poderá tornar-se recurso valioso para caracterização, diagnóstico e futuro estudo epidemiológico da PAF-TTR

Humans , Male , Female , Prealbumin/genetics , Epidemiologic Studies , Amyloid Neuropathies, Familial/diagnosis , Amyloid Neuropathies, Familial/genetics , Amyloidosis , Mutation/genetics , Genetic Testing , Surveys and Questionnaires
Braz. j. biol ; 81(3): 719-727, July-Sept. 2021. tab, graf
Article in English | LILACS | ID: biblio-1153409


Abstract Six different bread wheat genotypes; two Egyptian commercial varieties (control); Giza-168 and Gemmeiza-11, and four promising lines; L84 and L148, resulted via hybridization and M10 and M34 via radiation mutation program) were rheologically evaluated using extensograph and for protein, analysis using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The radiation mutant M10 and M34 had the highest maximum resistance which is a very good indicator of strong gluten. The amount of gluten content was higher in M10, L148, and M34 compared to the control samples Gz168 and Gm11. Sulfide amino acids (CYS and MET) are slightly higher in M10. The electrophoretic results and amino acid analyzers show that the best technological quality was exhibited by M10. Radiation mutants wheat genotypes have a protein with good characteristics, mainly gluten which is significantly higher compared to control samples. The rheological properties measured as extensograph and gel electrophoresis were much better in irradiated lines M10 and M34.

Resumo Seis diferentes genótipos de trigo de pão, duas variedades comerciais egípcias (controle) - Giza-168 e Gemmeiza-11 - e quatro linhas promissoras - L84 e L148, obtidas via hibridação, e M10 e M34, via programa de mutação por radiação - foram avaliados reologicamente por meio de extensógrafo, enquanto, para proteínas, foram feitas análises utilizando eletroforese em gel de poliacrilamida com dodecilsulfato de sódio (SDS-PAGE). Os mutantes de radiação M10 e M34 apresentaram a maior resistência máxima, o que é um indicador muito bom de glúten forte. A quantidade de glúten foi maior em M10, L148 e M34 em comparação com as amostras de controle Gz168 e Gm11. Os aminoácidos sulfurados (CYS e MET) são um pouco mais altos no M10. Os resultados eletroforéticos e analisadores de aminoácidos mostram que a melhor qualidade tecnológica foi exibida pelo M10. Os genótipos de trigo mutantes da radiação possuem uma proteína com boas características, principalmente o glúten, que é significativamente maior em comparação às amostras do grupo controle. As propriedades reológicas medidas, como extensógrafo e eletroforese em gel, foram muito melhores nas linhas irradiadas M10 e M34.

Bread , Flour , Triticum/genetics , Genotype , Glutens
Rev. colomb. obstet. ginecol ; 72(3): 307-318, July-Sept. 2021. tab, graf
Article in Spanish | LILACS | ID: biblio-1351955


Objetivo: describir el caso de una paciente con Síndrome de Li-Fraumeni (SLF) y cáncer de mama, en quien se cuestionó el beneficio en la supervivencia de la mastectomía profiláctica contralateral (MPC); asimismo, se pretende hacer una discusión crítica acerca de la evidencia que soporta este procedimiento en esta población. Presentación del caso: mujer de 37 años con cáncer de mama y múltiples antecedentes familiares de cánceres de temprana aparición del espectro del SLF, en quien, durante la adyuvancia hormonal, se confirmó una variante patogénica en el gen TP53. La paciente fue presentada en la Junta Multidisciplinaria del Servicio de Mama de un Centro Oncológico de referencia en Colombia, con el fin de discutir el beneficio de la MPC. La decisión de la junta fue no realizar la MPC. Después de 30 meses de seguimiento la paciente se encuentra libre de enfermedad. Conclusión: no existe evidencia que analice, de forma particular, el impacto de la MPC en la supervivencia de las pacientes con SLF y cáncer de mama. Sin embargo, a la luz del conocimiento actual no es posible generalizar la conducta de omitir esta cirugía profiláctica. Es importante reportar los casos en los que se decida realizar u omitir este procedimiento con el fin de incrementar el cuerpo de la evidencia, dado que existen limitaciones para construir grandes cohortes o estudios experimentales exclusivos para esta alteración genética.

Objective: To describe the case of a patient with Li-Fraumeni syndrome (LFS) and breast cancer in whom the benefit of contralateral prophylactic mastectomy (CPM) was challenged; and to offer a critical discussion regarding the evidence supporting this procedure in this patient population. Case presentation: A 37-year-old woman with breast cancer and a family history of multiple early onset cancer of the LFS spectrum in whom a pathogenic variant of the TP53 gene was confirmed during adjuvant hormonal therapy. The case was presented during the multidisciplinary meeting of the Breast Service of a referral oncology center in Colombia, in order to discuss the benefit of CPM. The decision of the board meeting was not to perform CPM. After 30 months of follow-up, the patient is disease-free. Conclusion: There is no evidence on the impact of CPM on survival of patients with LFS and breast cancer in particular. However, in light of the current knowledge, it is not possible to generalize the approach of withholding this prophylactic surgery. It is important to report those cases in which the decision is made to either perform or omit this procedure in order to increase the body of evidence, considering the limitations that make it difficult to build large cohorts or conduct trials exclusively for this genetic disorder.

Female , Adult , Breast Neoplasms , Li-Fraumeni Syndrome , Genes, p53 , Prophylactic Mastectomy
Int. j. med. surg. sci. (Print) ; 8(3): 1-11, sept. 2021. tab
Article in Spanish | LILACS | ID: biblio-1292528


El cáncer constituye la segunda de causa de muerte a nivel mundial y se estima será la primera, superando a las cardiovasculares. El estudio de sus bases moleculares ha permitido el desarrollo de la quimioterapia clásica, como de nuevas terapias biológicas. Si bien estos avances han redundado en un aumento en la sobrevida, no ha impactado en una menor incidencia de los casos. Esto último se debe, en parte, al desconocimiento de los múltiples factores carcinogénicos existentes y los efectos de sus interacciones para cada uno de los tumores. En este sentido, es interesante notar que, en los currículos de las escuelas de salud de las universidades chilenas, el cáncer u oncología como tal, no constituye una cátedra en sí misma, siendo sus contenidos tangencialmente abordados en distintos momentos de la formación; en biología celular, medicina interna y cirugía, entre otros. Con estos antecedentes, el propósito de este trabajo es ofrecer un propuesta sencilla y accesible para los estudiantes, respecto de los contenidos que, a nuestro juicio, son esenciales para comprender las bases biológicas de esta enfermedad y enfrentar con mejores conocimientos el ciclo clínico posterior. A continuación, el lector se encontrará con principios fundamentales de la biología humana normal (como el ciclo celular y el dogma central de la biología molecular), que permiten obtener una visión global de los mecanismos fisiológicos cuya desregulación conlleva a una neoplasia maligna. Luego se entregarán algunas definiciones amplias en relación con los conceptos de neoplasia, tumor benigno y maligno. Para, finalmente, abordar las principales etapas que permiten el desarrollo del cáncer; (i) iniciación, (ii) promoción y (iii) progresión. En esta última, se profundizará por separado, en angiogénesis, degradación de la matriz extracelular, migración y evasión de la respuesta inmune. Este trabajo no aborda materias relacionadas con la hipótesis metabólica del cáncer.

Cancer constitutes the second most common cause of death worldwide and is expected to become the leading one, even above cardiovascular diseases. The understanding of the cellular and molecular basis of cancer has led not only to the proper development of chemotherapy but also of target therapies. Although these advances are related with improved survival rates among cancer patients, it has poorly impacted its incidences. In this regard, the lack of knowledge regarding the impact that the several carcinogenic factors and their interactions have on different types of cancers may explain at least in part the difficulties to reduce incidence rates. However, is worth noticing that in several health schools of chilean universities, cancer does not constitute a formal course, being only partially approached during other courses, such as cell biology, internal medicine, and surgery. Thus, the aim of our work is to provide students a simple and resumed manuscript about essential topics necessary to understand the biological basis of cancer. First, the reader will find some fundamentals about human biology including the cell cycle and the central dogma of molecular biology, which offers an overview of the physiological mechanisms leading to malignant neoplasia. Then, we will provide current definitions of neoplasia, benign and malignant tumors are provided. Finally, the different stages of tumor progression will be approached to allow the understanding of cancer development. These stages include (i) initiation, (ii) promotion, and (iii) progression. For the last one, metastasis, angiogenesis, extracellular matrix degradation, migration, and immune evasion will also be addressed. This work will not consider the metabolic hypothesis of cancer.

Education, Medical, Undergraduate , Neoplasms/microbiology , Curriculum
Hematol., Transfus. Cell Ther. (Impr.) ; 43(3): 377-381, July-Sept. 2021. tab, ilus
Article in English | LILACS | ID: biblio-1346260


Myelodysplastic syndromes (MDS) are a heterogeneous group of hematological malignancies characterized by dysplasias, ineffective hematopoiesis and risk of acute myeloid leukemia transformation. Approximately 90% of MDS patients present mutations in genes involved in various cell signaling pathways. Specialized DNA polymerases, such as POLN, POLI, POLK, POLQ, POLH, POLL and REV3L, insert a nucleotide opposite replication-blocking DNA lesions in an error-prone manner and, in this way, sometimes can actively promote the generation of mutation. For the best of our knowledge, has not been described the mutations of these genes in MDS. DNA target sequencing CDS regions of the REV3L gene was performed in a 58-year-old man diagnosed as High Risk Myelodysplastic Syndrome. The patient presented very low hemoglobin, increased number of blasts, karyotype:47,XY,+8[6]/47,XY,del(7)(q32),+8[7], no response to hypomethylating therapy (decitabine), all markers of poor prognosis. Target sequencing identified a mutation c.9253-6T>C REV3L (Substitution - intronic) with VAF (variant allele frequency) = 16% considered pathogenic according to Functional Analysis through. Hidden Markov Models (FATHMM). This is the first evidence of REV3L mutation in MDS and, of utmost importance, associated with poor prognosis.

Humans , Male , Middle Aged , Myelodysplastic Syndromes , Prognosis
Rev. bras. cir. plást ; 36(3): 315-326, jul.-set. 2021. tab, graf
Article in Portuguese | LILACS-Express | LILACS | ID: biblio-1365553


RESUMO Introdução: As neoplasias cutâneas não melanoma representam o tipo mais frequente em ambos os sexos no mundo, sendo o carcinoma basocelular o mais prevalente, representando de 75 a 80% dos casos. No Brasil, o número de casos novos esperados para o triênio 2020-2022, será de 83.770 em homens e 93.160 em mulheres, correspondendo a um risco estimado de 80,12 casos novos para 100 mil homens e de 86,65 casos novos para 100 mil mulheres. Este dado demonstra a grande importância do conhecimento genômico na gênese do carcinoma basocelular esporádico. Objetivo: Descrever os principais genes e marcadores moleculares envolvidos na predisposição e na patogênese do carcinoma basocelular não sindrômico. Métodos: Revisão da literatura nas principais bases de dados NCBI-GTR, ClinVar, ClinGen, MedGen, OMIM e GeneReviews , utilizando como descritores: "BCC" e " basal cell carcinoma ". Critérios de inclusão: língua portuguesa ou inglesa, artigos sobre CBC esporádico. Resultados: Foram selecionados treze artigos para análise. A análise revelou uma robusta ligação da via hedgehog na gênese do carcinoma basocelular esporádico, com os principais genes envolvidos representados por PATCH1, PATCH2 e smoothened . As variantes com maior significância clínica foram SMO-M2, PTCH1 e PTCH2-∆22. A mutação mais encontrada fora a relacionada à ação do UVB, sendo representada pela substituição de C>T ou CC>TT no sítio das pirimidinas, tanto no PTCH, quanto no SMO. Conclusão: Extremamente importante aos profissionais que atuam no diagnóstico e tratamento do CBC, dentre os quais os cirurgiões plásticos, pois assim poderão melhor conduzir seus casos, com diagnósticos mais precisos e condutas de prevenção baseadas na suscetibilidade individual de cada paciente, bem como terapêuticas direcionadas e individualizadas com melhores taxas de sucesso.

ABSTRACT Introduction: Non-melanoma skin neoplasms represent the most frequent type in both sexes globally, with basal cell carcinoma being the most prevalent, representing 75 to 80% of cases. In Brazil, the number of new cases expected for the triennium 2020-2022 will be 83,770 in men and 93,160 in women, corresponding to an estimated risk of 80.12 new cases for 100,000 men and 86.65 new cases for 100,000 women. This data demonstrates the great importance of genomic knowledge in the genesis of sporadic basal cell carcinoma. Objective: To describe the main genes and molecular markers involved in the predisposition and pathogenesis of non-syndromic basal cell carcinoma. Methods: Literature review in the main databases NCBI-GTR, ClinVar, ClinGen, MedGen, OMIM and GeneReviews , using as descriptors: "BCC" and " basal cell carcinoma ". Inclusion criteria: Portuguese or EnGLIsh language, articles on sporadic BCC. Results: Thirteen articles were selected for analysis. The analysis revealed a robust hedgehog pathway link in the genesis of sporadic basal cell carcinoma, with the main genes involved represented by PATCH1, PATCH2 and smoothened . The variants with the highest clinical significance were SMO-M2, PTCH1 and PTCH2-∆22. The mutation most found was related to the action of UVB, being represented by the substitution of C>T or CC>TT at the pyrimidine site, both in PTCH and in SMO. Conclusion: Extremely important to professionals working in the diagnosis and treatment of BCC, including plastic surgeons, as this way they can better conduct their cases, with more accurate diagnoses and prevention approaches based on the individual susceptibility of each patient, as well as targeted therapies and individualized with better success rates.

Rev. bras. ginecol. obstet ; 43(6): 457-466, June 2021. tab, graf
Article in English | LILACS | ID: biblio-1341145


Abstract Objective Abnormalities in the eutopic endometrium of women with endometriosis may be related to disease-associated infertility. Although previous RNA-sequencing analysis did not show differential expression in endometrial transcripts of endometriosis patients, other molecular alterations could impact protein synthesis and endometrial receptivity. Our aim was to screen for functional mutations in the transcripts of eutopic endometria of infertile women with endometriosis and controls during the implantation window. Methods Data from RNA-Sequencing of endometrial biopsies collected during the implantation window from 17 patients (6 infertile women with endometriosis, 6 infertile controls, 5 fertile controls) were analyzed for variant discovery and identification of functional mutations. A targeted study of the alterations found was performed to understand the data into disease's context. Results None of the variants identified was common to other samples within the same group, and no mutation was repeated among patients with endometriosis, infertile and fertile controls. In the endometriosis group, nine predicted deleterious mutations were identified, but only one was previously associated to a clinical condition with no endometrial impact. When crossing the mutated genes with the descriptors endometriosis and/or endometrium, the gene CMKLR1 was associated either with inflammatory response in endometriosis or with endometrial processes for pregnancy establishment. Conclusion Despite no pattern of mutation having been found, we ponder the small sample size and the analysis on RNA-sequencing data. Considering the purpose of the study of screening and the importance of the CMKLR1 gene on endometrial

Resumo Objetivo Anormalidades no endométrio eutópico de mulheres com endometriose podem estar relacionadas à infertilidade associada à doença. Embora a análise prévia de sequenciamento de RNA não tenha evidenciado expressão diferencial em transcritos endometriais de pacientes com endometriose, outras alterações moleculares poderiam afetar a síntese de proteínas e a receptividade endometrial. Nosso objetivo foi rastrear mutações funcionais em transcritos de endométrios eutópicos de mulheres inférteis com endometriose e de controles durante a janela de implantação. Métodos Os dados do sequenciamento de RNA de biópsias endometriais coletados durante a janela de implantação de 17 pacientes (6 mulheres inférteis com endometriose, 6 controles inférteis, 5 controles férteis) foram analisados para a descoberta de variantes e a identificação de mutações funcionais. Um estudo direcionado das alterações encontradas foi realizado para compreender os dados no contexto da doença. Resultados Nenhuma das variantes identificadas foi comuma outras amostras dentro do mesmo grupo, assim como nenhuma mutação se repetiu entre pacientes com endometriose, controles inférteis e férteis. No grupo de endometriose, foram identificadas nove mutações deletérias preditas, mas apenas uma foi previamente associada a uma condição clínica sem impacto endometrial. Ao cruzar os genes mutados com os descritores endometriose e/ou endométrio, o gene CMKLR1 foi associado a resposta inflamatória na endometriose e a processos endometriais para estabelecimento da gravidez. Conclusão Apesar de nenhum padrão de mutação ter sido encontrado, ponderamos o pequeno tamanho da amostra e a análise dos dados de sequenciamento de RNA. Considerando o objetivo do estudo de triagem e a importância do gene CMKLR1 na modulação endometrial, este poderia ser um gene candidato para estudos adicionais que avaliem mutações no endométrio eutópico de pacientes com endometriose.

Humans , Female , Pregnancy , Embryo Implantation , Sequence Analysis, RNA , Endometriosis/complications , Endometriosis/genetics , Endometrium/metabolism , Infertility, Female/etiology , Mutation , Computer Simulation , Case-Control Studies , Prospective Studies , Receptors, Chemokine/genetics , Infertility, Female/metabolism
Rev. invest. clín ; 73(3): 132-137, May.-Jun. 2021. graf
Article in English | LILACS-Express | LILACS | ID: biblio-1280449


ABSTRACT Background: Fukuyama congenital muscular dystrophy (FCMD) is the most common form of a group of autosomal recessive disorders characterized by altered α-dystroglycan glycosylation and caused by FKTN gene mutations. However, mutations of this gene may cause a broad range of phenotypes, including Walker-Warburg syndrome, muscle-brain-eye disease, FCMD, limb-girdle muscular dystrophy without mental retardation, and cardiomyopathy with no or minimal skeletal muscle weakness. Objective: Our purpose was to describe two siblings who died at a young age with dilated cardiomyopathy (DCM), no muscle weakness, or atrophy, and were homozygous for a FKTN missense mutation. Methods: Site-directed next-generation sequencing (NGS) was performed. Pathogenicity of variants of interest was established according to the American College of Medical Genetics (ACMG) criteria, and all available first-degree relatives were screened for mutations by Sanger sequencing. Results: NGS revealed a homozygous FKTN variant in the index case (p.Gly424Ser, rs752358445), classified as likely pathogenic by ACMG criteria. Both parents and an unaffected brother were heterozygous carriers. Since the siblings had no apparent skeletal muscle weakness or central nervous system involvement, FKTN mutations were not initially suspected. Conclusions: This is the first report demonstrating that heterozygous individuals for the FKTN p.Gly424Ser mutation were healthy, while two homozygous brothers suffered severe DCM, strongly suggesting that this FKTN mutation is a rare cause of autosomal recessive DCM.

J. bras. nefrol ; 43(2): 279-282, Apr.-June 2021. graf
Article in English | LILACS-Express | LILACS | ID: biblio-1286942


Abstract Phosphopenic rickets may be caused by mutations in the PHEX gene (phosphate regulating endopeptidase homolog X-linked). Presently, more than 500 mutations in the PHEX gene have been found to cause hypophosphatemic rickets. The authors report a clinical case of a 4-year-old girl with unremarkable family history, who presented with failure to thrive and bowing of the legs. Laboratory tests showed hypophosphatemia, elevated alkaline phosphatase, normal calcium, mildly elevated PTH and normal levels of 25(OH)D and 1.25(OH)D. The radiological study showed bone deformities of the radius and femur. Clinical diagnosis of phosphopenic rickets was made and the genetic study detected a heterozygous likely pathogenic variant of the PHEX gene: c.767_768del (p.Thr256Serfs*7). This variant was not previously described in the literature or databases. Knowledge about new mutations can improve patient's outcome. Genetic analysis can help to establish a genotype-phenotype correlation.

Resumo O raquitismo fosfopênico pode ser causado por mutações no gene PHEX (ligado ao X do homólogo da endopeptidase que regula o fosfato). Atualmente, mais de 500 mutações no gene PHEX causam raquitismo hipofosfatêmico. Os autores relatam um caso clínico de uma menina de 4 anos com histórico familiar sem relevância, que apresentou falha no crescimento e arqueamento das pernas. Os exames laboratoriais mostraram hipofosfatemia, fosfatase alcalina elevada, cálcio normal, PTH levemente elevado e níveis normais de 25(OH)D e 1,25(OH)D. O estudo radiológico mostrou deformidades ósseas no rádio e no fêmur. O diagnóstico clínico do raquitismo fosfopênico foi realizado e o estudo genético detectou uma provável variante patogênica heterozigótica do gene PHEX: c.767_768del (p.Thr256Serfs*7). Esta variante não foi descrita anteriormente na literatura ou nas bases de dados. O conhecimento sobre novas mutações pode melhorar o desfecho de pacientes. A análise genética pode ajudar a estabelecer uma correlação genótipo-fenótipo.

Acta méd. peru ; 38(2): 151-153, abr.-jun 2021. tab
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1339027


RESUMEN Se reporta la frecuencia de mutaciones genéticas KatG e inhA que confieren resistencia a isoniacida en una muestra de 777 pacientes con resistencia a isoniacida. Se utilizó la prueba GenoType® MTBDRplus y la prueba de sensibilidad convencional por el método de agar en placa. Se encontró que 54 % presentó mutación en el gen KatG; este se asoció con resistencia a estreptomicina 76,6 % (p<0.05), rifampicina 66.7 % (p<0.05) y etionamida en un 33 % (p<0.05). La mutación en el gen inhA tuvo una frecuencia de 46 %, y se asoció con resistencia a etionamida en un 68,1 % (p<0.05), rifampicina 47,2 % (p<0,05) y estreptomicina 33 % (p<0,05). En estos pacientes, la presencia de genes que confieren resistencia a isoniazida se relacionó con resistencia a otros medicamentos antituberculosos.

ABSTRACT This a report of the frequency of KatG and inhA genetic mutations that confer resistance to isoniazid in a sample of 777 patients with resistance to isoniazid. GenoType® MTBDRplus test and conventional sensitivity tests by the agar plate method were used. It was found that 54% presented mutation in the KatG gene, associated with higher resistance to streptomycin 76.6% (p <0.05), rifampicin 66.7% (p <0.05) and ethionamide in 33% (p <0.05). inhA gene mutation has a frequency of 46% and was associated with resistance to ethionamide in 68.1% (p <0.05), rifampicin 47.2% (p <0.05) and streptomycin 33% (p <0.05). In this sample, the presences of mutations that confer resistance to isoniazid was associated with resistance to other antituberculosis drugs.

Rev. neuropsiquiatr ; 84(2): 113-127, abr.-jun. 2021. tab, graf
Article in Portuguese | LILACS-Express | LILACS | ID: biblio-1341577


RESUMO A doença neurodegenerativa mais comum no mundo é a doença de Alzheimer (DA), e 10% dos casos apresentam sintomas antes dos 65 anos, quase todos com associação genética, com hereditariedade autossômica dominante e penetrância entre 92 a 100% dos portadores. Na presente revisão, realizamos uma busca sobre as variantes genéticas associadas à doença de Alzheimer de início precoce (DAIP), enfatizando as características associadas mais importantes e as principais mutações já descritas. Os genes mais comumente relacionados com o surgimento da DAIP são APP, PSEN1, PSEN2 e MAPT, e mutações nestes afetam o metabolismo e a estrutura destas proteínas, resultando em acúmulos de peptídeo Aβ que causam inflamação e toxicidade no cérebro, levando à ativação da micróglia e promovendo a liberação de fatores neurotóxicos e pró-inflamatórios que aceleram a neurodegeneração. O gene PSEN1 é responsável por 70% das mutações conhecidas da DAIP, sendo a L166P associada à idade de ocorrência da doença abaixo dos 30 anos. Mutações em APP levam à agregação da proteína em placas neurodegenerativas. Todas as mutações descritas para MAPT estão associadas a um aumento dos emaranhados neurofibrilares. O polimorfismo E4 da Apolipoproteína E (APOE) influencia o aumento no risco de DAIP elevando as chances em três vezes para portadores heterozigotos e entre oito a dez vezes para os homozigotos. Apenas 5% das mutações associadas à DAIP são conhecidas, e novos estudos apresentam outros genes candidatos, bem como a importância de alterações epigenéticas na gênese desta doença.

SUMMARY The most common neurodegenerative disease in the world is Alzheimer's Disease (AD). Ten percent of Alzheimer patients experience symptoms before the age of 65, and almost all of them present genetic features of autosomal dominant inheritance nature, and penetrance of 92 to 100%. In the present review, we searched for genetic variants associated with early onset Alzheimer's disease (EOAD), emphasizing the most important characteristics and the main mutations. The genes most commonly related to the onset of EOAD are APP, PSEN1, PSEN2 and MAPT, whose mutations affect the metabolism and structure of these proteins. This process results in accumulations of Aβ peptide that leads to activation of the microglia and release of neurotoxic and pro-inflammatory factors that accelerate neurodegeneration. The PSEN1 gene is responsible for 70% of the known mutations in EOAD, while L166P is associated with below 30 years as the starting age of occurrence. APP mutations lead to protein aggregation in neurodegenerative plaques. All of the mutations described for MAPT are associated with an increase in neurofibrillary tangles. The E4 polymorphism of Apolipoprotein E (APOE) influences an increased risk of EOAD increasing up to three times the chances for heterozygous, and between eight and ten times for homozygotes carriers. Only 5% of the mutations associated with EOAD are known; new studies will show other candidate genes, as well as the importance of epigenetic factors changes in the etio-pathogenesis of this disease.

Rev. Assoc. Med. Bras. (1992) ; 67(2): 185-189, Feb. 2021. tab, graf
Article in English | LILACS | ID: biblio-1287803


SUMMARY OBJECTIVE: Colorectal cancer is the most common malignancy of the gastrointestinal tract. It is the third most common tumor in both genders and the second reason of cancer-related deaths. In recent years, tumor location has gained importance as a prognostic indicator. In this study, we aimed to analyze if there was a prognostic effect of tumor location, the pathological features, and the mutation status of patients on survival. METHODS: Two-hundred and ten colorectal cancer patients aged 18 years and older were included into the study. One-hundred and forty-two patients had left-sided tumor and 68 patients had right-sided tumor. Patients who had other malignancies rather than squamous cell skin cancer and in situ cervical cancer were excluded. All statistical tests were carried out using two-sided process, and a p≤0.05 was considered statistically significant. RESULTS: There were 140 men and 70 women in the study. The median age of the patients was 62 years old. There was no statistically significant difference according to tumor location and survival of patients. The overall survival of patients with right-sided tumors was 60.5 months and 47.2 months for left-sided tumors. Disease-free survival of patients was 63.7 months for right-sided tumors and 46 months for left-sided ones. Perineural invasion, grade and stage were crucial prognostic parameters. Disease-free survival was longer for female colorectal cancer patients. CONCLUSION: According to our study, survival of patients was similar regardless of tumor location. This can be explained by the different sequencing of treatment strategies and divergent population genetics.

Humans , Male , Female , Colorectal Neoplasms/genetics , Prognosis , Retrospective Studies , Disease-Free Survival , Middle Aged , Mutation