Tamoxifen treatment of breast cancer cells: Impact on Hedgehog/GLI1 signaling

The selective estrogen receptor (ER) modulator tamoxifen (TAM) has become the standard therapy for the treatment of ER+ breast cancer patients. Despite the obvious benefits of TAM, a proportion of patients acquire resistance to treatment, and this is a significant clinical problem. Consequently, the identification of possible mechanisms involved in TAM-resistance should help the development of new therapeutic targets. In this study, we present in vitro data using a panel of different breast cancer cell lines and demonstrate the modulatory effect of TAM on cellular proliferation and expression of Hedgehog signaling components, including the terminal effector of the pathway, the transcription factor GLI1. A variable pattern of expression following TAM administration was observed, reflecting the distinctive properties of the ER+ and ER− cell lines analyzed. Remarkably, the TAM-induced increase in the proliferation of the ER+ ZR-75-1 and BT474 cells parallels a sustained upregulation of GLI1 expression and its translocation to the nucleus. These findings, implicating a TAM-GLI1 signaling cross-talk, could ultimately be exploited not only as a means for novel prognostication markers but also in efforts to effectively target breast cancer subtypes

Determinación del polimorfismo C677T de metilentetrahidrofolato reductasa (MTHFR) en una población piloto de estudiantes de la Universidad del Rosario

 Introduction: the 5, 10-methylenetetrahydrofolate reductase (MTHFR) is an essential enzyme in folate metabolism; their polymorphisms have been associated with heart disease risk increase, obstetric problems, neural tube defects in fetuses and cancer susceptibility. This gene has a single nucleotide polymorphism, a C-T change at nucleotide 677, which affects significantly its enzymatic activity. Objective: because of the biological importance of this enzyme and the Colombian population genetic heterogeneity characteristic, a study was performed to determine allele and genotype frequencies of MTHFR C677T polymorphism in healthy individuals, taking into account that in Colombia there are only studies that have involved case-control methodology. Methods: we analyzed this polymorphism trough the amplification of the DNA of a 206 students sample population. Additionally, Colombian overall frequencies were calculated, using data from healthy controls reported in other studies. Results: a Hardy-Weinberg disequilibri m was found in the sample tested. For the Colombian data, we found that the global population was in equilibrium. Conclusion: T allele population frequency seems to be under positive selection pressure, which is reflected in the population allele increase, despite its deleterious effect. A Spanish study reported similar results and identified folic acid supplementation on expectant mothers as a probably cause of this change. Introducción: la 5, 10-metilentetrahidrofolato reductasa (MTHFR) es una enzima clave en el metabolismo del folato; sus polimorfismos se han asociado al aumento de riesgo de padecer enfermedad coronaria, problemas obstétricos en mujeres gestantes, desarrollo de fetos con defectos de cierre del tubo neural y susceptibilidad a algunos tipos de cáncer. Este gen presenta una variación polimórfica de nucleótido único, que consiste en un cambio de C por T en la posición 677 el cual afecta de manera notable su actividad enzimática. Objetivo: Dada la importancia de esta enzima y la heterogeneidad genética de la población colombiana se realizó un estudio para determinar las frecuencias alélicas y genotípicas del polimorfismo C677T de MTHFR en individuos sanos, debido a que en el país sólo se han realizado estudios que involucran metodología de casos y controles. Materiales y métodos: Este polimorfismo se estudió a partir de ADN de una muestra poblacional de 206 estudiantes. Adicionalmente, se calcularon las frecuencias globales de Colombia utilizando los datos de controles sanos reportados en otros estudios. Resultados: En la muestra evaluada se detectó un desequilibrio Hardy-Weinberg, mientras que en los datos globales colombianos se encontró que la población está en equilibrio. Conclusión: la frecuencia poblacional del alelo T parece estar sometida a una presión de selección positiva, dado su incremento en la población a pesar de su efecto deletéreo. Un estudio español reporta resultados similares y argumenta como causa probable de este cambio en la frecuencia alélica de T la suplementación con ácido fólico a futuras madres

Sporadic Creutzfeldt-Jakob disease: Clinical, pathological and molecular study

Generalidades. Las encefalopatías espongiformes transmisibles son enfermedades neurodegenerativas ocasionadas por la acumulación anormal de una variante mal plegada de la proteína priónica, lo cual induce la formación de conglomerados proteicos resistentes a la degradación. Además, son responsables de la disfunción sináptica, daño neuronal y de la sintomatología clásica acompañante. Esta proteína de membrana es codificada por el exón 2 del gen PRNP, ubicado en el brazo corto del cromosoma 20 y parece estar involucrada en la trasmisión sináptica, la transducción de señales, la actividad antioxidante de la superoxidodismutasa, neuroplasticidad y sobrevida celular. Un polimorfismo en el codón 129 se asocia con una susceptibilidad diferencial a la enfermedad Creutzfeldt-Jakob esporádica. Objetivo. Estudio clínico, patológico y molecular de un caso de una mujer de 58 años con diagnóstico de enfermedad de Creutzfeldt- Jakob esporádica. Métodos y resultados. Se presenta el caso de una mujer en quien aparece un trastorno depresivo del afecto con demencia progresiva y sintomatología general. Al final de la enfermedad, el cuadro progresó a un déficit neurológico focalizado en el área visual. La RMN mostró hiperintensidades inespecíficas córtico-subcorticales en el núcleo estriado; en el EEG se encontró pérdida de ritmos de fondo, patrón de descargas periódicas generalizadas y complejos trifásicos; en la biopsia cerebral postmorten se evidenció pérdida severa de la población neuronal en todas las capas, vacuolas en el neuropil, en el soma neuronal y en la glía. El análisis de secuencia del gen PRNP, a partir de extracción de DNA de sangre periférica, identificó homocigosis para metionina en el codón 129. La paciente fallece a los 3 meses del inicio de la sintomatología. Conclusión. Por epidemiología, curso clínico y exámenes paraclínicos se confirma el diagnóstico de enfermedad de Creutzfeldt- Jakob esporádica.La determinación del genotipo para los polimorfismos de riesgo se convierte en una herramienta útil para complementar por medios moleculares el diagnóstico y para profundizar la comprensión de la fisiopatología de la enfermedad de Creutzfeldt-Jakob, tanto para formas esporádicas como para la nueva variante.Background: Transmissible spongiform encephalopathies are neurodegenerative diseases caused by abnormal accumulation of pathogenic isoform the prion protein, which induces the formation of conglomerates protein resistant to degradation. They are also responsible for synaptic dysfunction, neuronal damage and the classic symptoms of disease. This membrane protein is encoded by exon 2 of the gene PRNP, located on the short arm of chromosome 20 and appears to be involved in synaptic transmission, signal transduction, the antioxidant activity of the superoxid dismutasa, neuroplasticity and cell survival. One polymorphism at codon 129 is associated with differential susceptibility to disease sporadic Creutzfeldt-Jakob disease. Aim: Clinical, pathological and molecular report on an 58 year-old woman with pathological diagnosis of Creutzfeldt-Jakob sporadic disease. Methods and results. The clinic course appears with a behavior depressive disorder with progressive dementia and symptoms. At the end of the disease, the scenario progressed to a neurological deficit focused on the visual area. The MRI showed nonspecific hyperintensity in cortiço-subcortical nucleus in the striatum, the EEG showed patterns of recurrent generalized discharges and complex three-phase, the brain biopsy post-morten showed severe loss of the neuronal population in all the layers, vacuoles in the neuropil, in the neuronal soma and the glial. The analysis of sequence of the gene PRNP identified homozygotes for methionine at codon 129. The patient died at 3 months of the onset of symptoms. Conclusions: Epidemiology, clinical course and paraclinical examinations confirmed the diagnosis of Creutzfeldt-Jakob sporadic. The genotyping for polymorphisms of risk becomes useful tool to complement through molecular diagnosis and to deepen the understanding of the pathophysiology of Creutzfeldt- Jakob disease, both for sporadic forms and for the new variant

Friedreich’s Ataxia: Phenotype and Genotype in Eleven Patients

Introducción: La ataxia de Friedreich (FRDA) es una enfermedad autosómica recesiva debida a una mutación en el gen X25. Dicho gen está localizado en el cromosoma 9 y codifica para la proteína frataxina. La enfermedad es causada por la repetición del trinucleótido GAA. En individuos normales la secuencia GAA se encuentra repetida entre siete y veintidós veces, mientras que, en pacientes con ataxia de Friedreich GAA puede estar repetida cientos o miles de veces.Objetivos: Evaluar si existe correlación entre el tamaño de la expansión, la edad de inicio de FRDA y su severidad en la muestra seleccionada.Métodos:- Se estudiaron once pacientes con fenotipo típico de ataxia de Friedreich. El análisis molecular por PCR determinó la expansión del trinucleótido GAA. Se analizó la correlación entre la edad de inicio de FRDA y su progresión con el número de repeticiones GAA.Resultados y conclusiones:- El análisis molecular por PCR mostró ocho pacientes homocigotos para la expansión, y tres negativos. El promedio del tamaño de las expansiones en los alelos es 622±5 con un promedio correspondiente de la edad inicio de FRDA 13±8. Para el tamaño de la muestra no se observó una correlación estadística significativa entre la edad de inicio de la enfermedad y el número de repeticiones, pero sí una tendencia a correlacionarse de forma inversa (p<0.11). El diagnóstico molecular de FRDA, sumado a la comprensión de su fisiología y a la utilización de los criterios de inclusión de Harding, constituye un paso importante en el logro de un tratamiento óptimo de la enfermedad.Introduction:- Friedreich’s ataxia is an autosomal recessive disease due to a mutation in gene X25. This gene codes for frataxin and it is located on chromosome 9. The disease is caused by a triplet particular sequence of bases (GAA). Normally, the GAA sequence is repeated 7 to 22 times, but in people with Friedreich’s ataxia, it can be repeated hundreds or even over thousand times. Objectives:To determine if there is a correlation between clinical and molecular findings in our FRDA patients. Methods: Eleven patients with the typical Friedreich´s ataxia phenotype were studied by PCR we determined the size of the GAA expansions, and analyzed the correlation of age at onset and rate of disease progression with the number of GAA repetitions. Results and conclusions: Molecular analysis by PCR showed eight homozygous patients for the expansion and three negative. The average of the size of the expansions in the allele was of 622±5 with an average in the age of beginning of 13±8. For the sample size, there was no significant statistical correlation between the age of beginning of the disease and the number of repetitions, although there was like an inverse correlation. Besides understanding of FRDA physiology and the Harding clinical inclusion criteria, molecular diagnosis is an important step in the achievement of an optimal therapeutic treatment

Vaccination of Gilthead Seabream After Continuous Xenoestrogen Oral Exposure Enhances the Gut Endobolome and Immune Status via GPER1

In fish culture settings, the exogenous input of steroids is a matter of concern. Recently, we unveiled that in the gilthead seabream (Sparus aurata), the G protein-coupled estrogen receptor agonist G-1 (G1) and the endocrine disruptor 17α-ethinylestradiol (EE2) are potent modulators in polyreactive antibody production. However, the integral role of the microbiota upon immunity and antibody processing in response to the effect of EE2 remains largely unexplored. Here, juvenile seabreams continuously exposed for 84 days to oral G1 or EE2 mixed in the fish food were intraperitoneally (i.p.) immune primed on day 42 with the model antigen keyhole limpet hemocyanin (KLH). A critical panel of systemic and mucosal immune markers, serum VTG, and humoral, enzymatic, and bacteriolytic activities were recorded and correlated with gut bacterial metagenomic analysis 1 day post-priming (dpp). Besides, at 15 dpp, animals received a boost to investigate the possible generation of specific anti-KLH antibodies at the systemic and mucosal interphases by the end of the trial. On day 43, EE2 but not G1 induced a significant shift in the serum VTG level of naive fish. Simultaneously, significant changes in some immune enzymatic activities in the serum and gut mucus of the EE2-treated group were recorded. In comparison, the vaccine priming immunization resulted in an attenuated profile of most enzymatic activities in the same group. The gut genes qPCR analysis exhibited a related pattern, only emphasized by a significant shift in the EE2 group’s il1b expression. The gut bacterial microbiome status underwent 16S rRNA dynamic changes in alpha diversity indices, only with the exposure to oral G1, supporting functional alterations on cellular processes, signaling, and lipid metabolism in the microbiota. By the same token, the immunization elevated the relative abundance of Fusobacteria only in the control group, while this phylum was depleted in both the treated groups. Remarkably, the immunization also promoted changes in the bacterial class Betaproteobacteria and the estrogen-associated genus Novosphingobium. Furthermore, systemic and mucosal KLH-specific immunoglobulin (Ig)M and IgT levels in the fully vaccinated fish showed only slight changes 84 days post-estrogenic oral administration. In summary, our results highlight the intrinsic relationship among estrogens, their associated receptors, and immunization in the ubiquitous fish immune regulation and the subtle but significant crosstalk with the gut endobolome.Versión del edito

Prevalence of BRCA1 and BRCA2 germline mutations in patients of african descent with early-onset and familial Colombian breast cancer

Q2Q1Familias afrocolombianas afectadas por cáncer de mama y ovarioBackground: Pathogenic germline mutations in the BRCA1 and BRCA2 (BRCA1/2) genes contribute to hereditary breast/ovarian cancer (OC) in White/mestizo Colombian women. As there is virtually no genetic data on breast cancer (BC) in Colombians of African descent, we conducted a comprehensive BRCA1/2 mutational analysis of 60 Afro-Colombian families affected by breast/OC. Materials and Methods: Mutation screening of the complete BRCA1/2 genes for small-scale mutations and large genomic alterations was performed in these families using next-generation sequencing and multiplex ligation-dependent probe amplification analysis. Results: Four pathogenic germline mutations, including one novel mutation, were identified, comprising 3 in BRCA1 and one in BRCA2. The prevalence of BRCA1/2 mutations, including one BRCA1 founder mutation (c.5123C>A) previously identified in this sample set, was 3.9% (2/51) in female BC-affected families and 33.3% (3/9) in those affected by both breast and OC. Haplotype analysis of 2 BRCA2_c.2701delC carriers (one Afro-Colombian and one previously identified White/mestizo Colombian patient with BC) suggested that the mutation arose in a common ancestor. Conclusion: Our data showed that 2/5 (40%) mutations (including the one previously identified in this sample set) are shared by White/mestizo Colombian and Afro-Colombian populations. This suggests that these 2 populations are closely related. Nevertheless, variations in the BRCA1/2 mutational spectrum among Afro-Colombian subgroups from different regions of the country were observed, suggesting that specific genetic risk assessment strategies need to be developed.https://orcid.org/0000-0002-1903-9621https://orcid.org/0000-0001-6444-7248https://orcid.org/0000-0002-3649-9515https://orcid.org/0000-0002-9879-9775Revista Internacional - IndexadaA1N

Microbiological testing of adults hospitalised with community-acquired pneumonia: An international study

This study aimed to describe real-life microbiological testing of adults hospitalised with community-acquired pneumonia (CAP) and to assess concordance with the 2007 Infectious Diseases Society of America (IDSA)/American Thoracic Society (ATS) and 2011 European Respiratory Society (ERS) CAP guidelines. This was a cohort study based on the Global Initiative for Methicillin-resistant Staphylococcus aureus Pneumonia (GLIMP) database, which contains point-prevalence data on adults hospitalised with CAP across 54 countries during 2015. In total, 3702 patients were included. Testing was performed in 3217 patients, and included blood culture (71.1%), sputum culture (61.8%), Legionella urinary antigen test (30.1%), pneumococcal urinary antigen test (30.0%), viral testing (14.9%), acute-phase serology (8.8%), bronchoalveolar lavage culture (8.4%) and pleural fluid culture (3.2%). A pathogen was detected in 1173 (36.5%) patients. Testing attitudes varied significantly according to geography and disease severity. Testing was concordant with IDSA/ATS and ERS guidelines in 16.7% and 23.9% of patients, respectively. IDSA/ATS concordance was higher in Europe than in North America (21.5% versus 9.8%; p&lt;0.01), while ERS concordance was higher in North America than in Europe (33.5% versus 19.5%; p&lt;0.01). Testing practices of adults hospitalised with CAP varied significantly by geography and disease severity. There was a wide discordance between real-life testing practices and IDSA/ATS/ERS guideline recommendations

Prevalence and etiology of community-acquired pneumonia in immunocompromised patients

Background. The correct management of immunocompromised patients with pneumonia is debated. We evaluated the prevalence, risk factors, and characteristics of immunocompromised patients coming from the community with pneumonia. Methods. We conducted a secondary analysis of an international, multicenter study enrolling adult patients coming from the community with pneumonia and hospitalized in 222 hospitals in 54 countries worldwide. Risk factors for immunocompromise included AIDS, aplastic anemia, asplenia, hematological cancer, chemotherapy, neutropenia, biological drug use, lung transplantation, chronic steroid use, and solid tumor. Results. At least 1 risk factor for immunocompromise was recorded in 18% of the 3702 patients enrolled. The prevalences of risk factors significantly differed across continents and countries, with chronic steroid use (45%), hematological cancer (25%), and chemotherapy (22%) the most common. Among immunocompromised patients, community-acquired pneumonia (CAP) pathogens were the most frequently identified, and prevalences did not differ from those in immunocompetent patients. Risk factors for immunocompromise were independently associated with neither Pseudomonas aeruginosa nor non\u2013community-acquired bacteria. Specific risk factors were independently associated with fungal infections (odds ratio for AIDS and hematological cancer, 15.10 and 4.65, respectively; both P = .001), mycobacterial infections (AIDS; P = .006), and viral infections other than influenza (hematological cancer, 5.49; P < .001). Conclusions. Our findings could be considered by clinicians in prescribing empiric antibiotic therapy for CAP in immunocompromised patients. Patients with AIDS and hematological cancer admitted with CAP may have higher prevalences of fungi, mycobacteria, and noninfluenza viruses

Atypical pathogens in hospitalized patients with community-acquired pneumonia: A worldwide perspective

Background: Empirical antibiotic coverage for atypical pathogens in community-acquired pneumonia (CAP) has long been debated, mainly because of a lack of epidemiological data. We aimed to assess both testing for atypical pathogens and their prevalence in hospitalized patients with CAP worldwide, especially in relation with disease severity. Methods: A secondary analysis of the GLIMP database, an international, multicentre, point-prevalence study of adult patients admitted for CAP in 222 hospitals across 6 continents in 2015, was performed. The study evaluated frequency of testing for atypical pathogens, including L. pneumophila, M. pneumoniae, C. pneumoniae, and their prevalence. Risk factors for testing and prevalence for atypical pathogens were assessed through univariate analysis. Results: Among 3702 CAP patients 1250 (33.8%) underwent at least one test for atypical pathogens. Testing varies greatly among countries and its frequency was higher in Europe than elsewhere (46.0% vs. 12.7%, respectively, p &lt; 0.0001). Detection of L. pneumophila urinary antigen was the most common test performed worldwide (32.0%). Patients with severe CAP were less likely to be tested for both atypical pathogens considered together (30.5% vs. 35.0%, p = 0.009) and specifically for legionellosis (28.3% vs. 33.5%, p = 0.003) than the rest of the population. Similarly, L. pneumophila testing was lower in ICU patients. At least one atypical pathogen was isolated in 62 patients (4.7%), including M. pneumoniae (26/251 patients, 10.3%), L. pneumophila (30/1186 patients, 2.5%), and C. pneumoniae (8/228 patients, 3.5%). Patients with CAP due to atypical pathogens were significantly younger, showed less cardiovascular, renal, and metabolic comorbidities in comparison to adult patients hospitalized due to non-atypical pathogen CAP. Conclusions: Testing for atypical pathogens in patients admitted for CAP in poorly standardized in real life and does not mirror atypical prevalence in different settings. Further evidence on the impact of atypical pathogens, expecially in the low-income countries, is needed to guidelines implementation

Burden and risk factors for Pseudomonas aeruginosa community-acquired pneumonia:a Multinational Point Prevalence Study of Hospitalised Patients

Pseudornonas aeruginosa is a challenging bacterium to treat due to its intrinsic resistance to the antibiotics used most frequently in patients with community-acquired pneumonia (CAP). Data about the global burden and risk factors associated with P. aeruginosa-CAP are limited. We assessed the multinational burden and specific risk factors associated with P. aeruginosa-CAP. We enrolled 3193 patients in 54 countries with confirmed diagnosis of CAP who underwent microbiological testing at admission. Prevalence was calculated according to the identification of P. aeruginosa. Logistic regression analysis was used to identify risk factors for antibiotic-susceptible and antibiotic-resistant P. aeruginosa-CAP. The prevalence of P. aeruginosa and antibiotic-resistant P. aeruginosa-CAP was 4.2% and 2.0%, respectively. The rate of P. aeruginosa CAP in patients with prior infection/colonisation due to P. aeruginosa and at least one of the three independently associated chronic lung diseases (i.e. tracheostomy, bronchiectasis and/or very severe chronic obstructive pulmonary disease) was 67%. In contrast, the rate of P. aeruginosa-CAP was 2% in patients without prior P. aeruginosa infection/colonisation and none of the selected chronic lung diseases. The multinational prevalence of P. aeruginosa-CAP is low. The risk factors identified in this study may guide healthcare professionals in deciding empirical antibiotic coverage for CAP patients