C-Fos-activated circRPPH1 contributes to glioma stemness

Objective Cancer stem cells or cancer stemness has been confirmed to a major obstacle for glioma progression and it has also been reported that circRNAs play an important part in cancer progression. This study mainly focuses on revealing the role of circRPPH1 and the underlying mechanisms in glioma cell stemness. Methods In vitro experiment including RT-qPCR, Western blot, sphere-formation analysis, and ALDH1 activity, and in vivo tumorigenesis experiments were performed to evaluate the effects of circRPPH1 on glioma cell stemness. Luciferase reporter, ChIP, and DNA pull-down analysis were used to reveal the underlying mechanisms. Results It was found that circRPPH1 level was upregulated in glioma cell spheres and facilitated the stemness of glioma cells; C-FOS transcriptionally activated circRPPH1 expression via directly binding to circRPPH1 promoter in glioma cells. Moreover, circRPPH1 promoted the stemness of glioma cells dependent on c-FOS-mediated transcriptional activation. Conclusions This study indicates that c-Fos-activated circRPPH1 contributes to glioma stemness and provides a potential target for glioma progression based on the c-FOS/circRPPH1 regulatory axis (AU)

Polimorfismos en la región promotora del gen de IL10 y su asociación con la enfermedad celiaca / No disponible

INTRODUCCIÓN: en la enfermedad celiaca (EC), la activación de la respuesta inmune lleva a una alteración de la red local de citoquinas. La IL-10 es una citoquina antiinflamatoria esencial en la prevención de patologías inflamatorias. OBJETIVO: analizar la asociación de polimorfismos de nucleótido simple ubicados en el promotor del gen de interleuquina 10 con la EC, en una población de la provincia de Misiones, Argentina. PACIENTES Y MÉTODOS: se extrajo ADN de sangre entera de 40 pacientes con EC y de 80 controles y se amplificó una región en el promotor del gen de IL10 que contiene los polimorfismos rs1800896A/G, rs1800871T/C y rs1800872A/C. Se estableció el riesgo mediante el cálculo de odds ratios (OR), considerando estadísticamente significativo un p < 0,05. RESULTADOS: entre pacientes celiacos y controles no se observaron diferencias significativas en la distribución de los genotipos del polimorfismo rs1800896. La frecuencia de los genotipos CC de rs1800871T/C y rs1800872A/C fue menor en los celiacos (35 % vs. 65 %; p = 0,002). Presentaron riesgo de EC los portadores del alelo menos frecuente T del rs1800871T/C y del alelo menos frecuente A del rs1800872A/C con un modelo dominante (OR = 2,79; IC 95 %: 1,27-6,09; p = 0,01). Se encontró un efecto de riesgo del haplotipo ATA (OR = 3,05; IC 95 %: 1,25-7,46; p = 0,01). CONCLUSIÓN: los portadores del alelo menos frecuente T del rs1800871T/C y del alelo menos frecuente A del rs1800872A/C en el promotor del gen IL10 presentan riesgo elevado de EC con un modelo dominante, sin mostrar riesgo para el rs1800896A/G. El haplotipo ATA muestra asociación para el desarrollo de EC

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La epigenética como herramienta diagnóstica y pronóstica en la estenosis pieloureteral / Epigenetics as a diagnostic and prognostic tool for pyeloureteral stenosis

Objetivo: En los últimos años, numerosos estudios se han centrado en la genética del sistema renal. Betchel et al. en 2010, demostraron como la metilación, fenómeno epigenético, estaría implicado en la perpetuación de la fibrosis. En nuestro estudio queremos demostrar si la epigenética tiene relación con la estenosis pieloureteral y en caso de ser así, si podría ser utilizada como material pronóstico y diagnóstico. Material y métodos: Se ha realizado un estudio descriptivo observacional o transversal en el que se analizó la metilación en el ADN extraído de las muestras de unión pieloureteral en pacientes pediátricos obtenidas durante la cirugía entre 1999 y 2015, resultando un total de 20 pacientes. Los datos clínicos-radiológicos se analizaron según correlación y agrupación de los mismos mediante un paquete software filogenético/estadístico denominado PHYLIP de acceso libre gratuito. Los genes seleccionados sobre los que se realizó la PCR específica de metilación (MSP) fueron: p16, RASSF1A, MGMT, Ciclina D-2, HIN-1, E-Cadherina y RASAL-1. Resultados: Los datos clínico-radiológicos analizados filogenéticamente mediante el programa PHYLIP establecieron 7 grupos de pacientes. Los resultados con respecto a la metilación mostraron una proporción considerable de metilación aberrante en la región del promotor de los genes p16 (25%), MGMT (15%), E-Cadherina (25%),HIN-1 (25%) y RASAL-1 (35%). Se analizó la asociación de los grupos clínico-radiológicos con los estados de metilación/no metilación de cada gen. Conclusiones: Se demuestra que la metilación sí tiene un papel en la fibrosis desarrollada en la estenosis pieloureteral destacando dos patrones clínicos de mal pronóstico asociados a dos clusters epigenéticos de metilación. RASAL-1, E-Cadherina, HIN-1 y p16 serían los candidatos para desarrollar estudios futuros sobre sus implicaciones pronósticas en la estenosis pieloureteral

Objective: In the last few years, numerous studies have focused on the genetics of the renal system. Betchel et al in 2010 demonstrated that methylation, as a epigenetic phenomenon, would be involved in the perpetuation of fibrosis. In our study, we want to demonstrate whether epigenetics is related to pyeloureteral stenosis and, if that is the case, if it could be used as prognostic and diagnostic biomarker. Methods: This is a descriptive observational and cross-sectional study that analyzed the methylation in DNA extracted from pyeloureteral junction samples obtained from surgery in pediatric patients in the period from 1999 to 2015, resulting in a total of 20 patients. Clinical data were analyzed using correlation tests and they were grouped with a free access software statistical phylogenetic package called PHYLIP. The selected genes for methylation-specific PCR (MSP) were the following: p16, RASSF1A, MGMT, Cyclin D-2, HIN-1, E-Cadherin and RASAL-1. Results: The clinical-radiological data analyzed phylogenetically by the PHYLIP program established 7 groups of patients. The results of methylation showed a considerable proportion of aberrant methylation in the promotor region of the genes p16 (25%), MGMT (15%), E-Cadherin (25%), HIN-1 (25%) and RASAL-1 (35%). The association of the clinical-radiological groups with methylation/non-methylation states of each gene was also analyzed. Conclusions: This study demonstrates that methylation does have a role in fibrosis developed in pyeloureteral stenosis. Two clinical patterns of poor prognosis associated with two epigenetic methylation cluster. RASAL-1, E-Cadherin, HIN-1 and p16 would be candidates for future studies on their prognostic implications in pyeloureteral stenosis

The -2549 -2567 del18 polymorphism in VEGF and irreversible bronchoconstriction in asthmatics

BACKGROUND: While the importance of vascular endothelial growth factor (VEGF) in the pathogenesis of several diseases (eg, neoplasms) has been proven, its role in asthma, especially in terms of the potential associations between genetic variants of VEGF and airway remodeling, has received relatively little attention. OBJECTIVES: This study aimed to evaluate the possible connection between a genetic factor, ie, the polymorphism del/ins in the VEGF promoter region, and airway remodeling potential in asthmatics with and without irreversible bronchoconstriction. MATERIALS AND METHODS: The study population comprised 82 patients with asthma (of whom 42 had irreversible bronchoconstriction) and a group of 40 controls. DNA was isolated from peripheral blood leukocytes. Polymerase chain reaction was used to type the VEGF (18-bp deletion/insertion) gene polymorphism at loci -2549 -2567. Other factors (ie, smoking, disease duration) were also taken into consideration. RESULTS: The del/del genotype was found in 74.39% of patients with asthma (P=.031; OR=2.38), 80.95% of patients with irreversible bronchoconstriction (P=.012; OR=3.48), and 67.5% patients with reversible bronchoconstriction (P=.251; OR=1.70). The proportion of smokers to nonsmokers was higher (P=.032) and disease duration was longer (P=.041) in patients with irreversible bronchoconstriction than in those with reversible bronchoconstriction. CONCLUSIONS: Our results showed that the risk of irreversible bronchoconstriction in asthmatics was associated with the presence of the del18 genotype at the -2549 -2567 position in the promoter region of the VEGF gene, as were disease duration and other factors such as smoking

ANTECEDENTES: Aunque se ha demostrado la importancia del factor de crecimiento endotelial vascular (VEGF) en la patogénesis de varias enfermedades (p. ej. neoplasias), los datos relativos al asma son escasos, especialmente los relacionados con las posibles asociaciones entre las variantes genéticas de VEGF y la remodelación de las vías respiratorias. OBJETIVOS: En este estudio se propuso evaluar la posible relación entre un factor genético como el polimorfismo del/ins en la región promotora de VEGF y el potencial de remodelación de las vías aéreas en los asmáticos con y sin broncoconstricción irreversible. MATERIALES Y MÉTODOS: en el estudio participaron 82 pacientes con asma (42 pacientes con broncoconstricción irreversible) y un grupo de 40 controles. El ADN fue extraído de leucocitos de sangre periférica. Para la tipificación del polimorfismo del gen VEGF (delección / inserción de 18 pb) en loci -2549 -2567 se utilizó el método de reacción en cadena de la polimerasa (PCR). Se consideraron también otros factores (fumar, duración de la enfermedad). RESULTADOS: El genotipo del/del se encontró en el 74,39% de pacientes con asma (p = 0,031; OR = 2,38), el 80,95% de los pacientes con broncoconstricción irreversible (p = 0,012; OR = 3,48) y el 67,5% de los pacientes con broncoconstricción reversible (p = 0,251; OR = 1,70). La proporción de fumadores con respecto a los no fumadores fue mayor (p = 0,032) y la duración de la enfermedad fue mayor en pacientes con broncoconstricción irreversible en comparación con aquellos con broncoconstricción reversible (p = 0,041). CONCLUSIONES: Nuestros resultados mostraron que la presencia del genotipo del18 en la posición -2549 -2567, en el promotor del gen VEGF, junto con la duración de la enfermedad y otros factores como fumar cigarrillos, se asocian con el riesgo de broncoconstricción irreversible en los individuos asmáticos

Germline promoter hypermethylation in BRCA1 and BRCA2 genes is not present in hereditary breast cancer patients

Purpose: Germline promoter hypermethylation of BRCA1 and BRCA2 genes is an alternative event of gene silencing that has not been widely investigated in hereditary breast and ovarian cancer (HBOC) syndrome. Methods: We analyzed germline BRCA promoter hypermethylation in HBOC patients with and without BRCA mutations and control subjects, using a recently developed BRCA methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) assay. Results: Neither the patients tested nor the control subjects showed germline hypermethylation of the BRCA1 and BRCA2 promoter regions analyzed. Conclusions: Despite the results achieved at somatic levels by other researchers, these were not confirmed in our study at the germline level. Our results show the need to establish more predictive CpG sites in the BRCA promoter regions to optimize the MS-MLPA assay for the detection of germline hypermethylation as an effective pre-screening tool for whole-BRCA genetic analysis in HBOC, because we can not rule out the existence of germline promoter hypermethylation in BRCA

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The B2 - adrenoreceptor gene promoter polymorphisms may modulate B2 - agonist and glucocorticoid-induced IgE synthesis

BACKGROUND: β2-adrenoreceptor (β2-AR) agonists and glucocorticoids (GCS) were shown to induce IgE synthesis in human PBMCs. Serum total IgE levels are associated with single nucleotide polymorphisms (SNPs) of the β2-AR gene. We aimed to assess the association of the effect of fenoterol (β2-AR agonist) on IL-4-driven and budesonide-induced IgE synthesis with genetic variants of β2-AR. METHODS: The study included 25 individuals: 13 with allergic asthma and/or allergic rhinitis and 12 healthy volunteers. PBMCs were cultured with IL-4, fenoterol and/or budesonide, and IgE concentrations in supernatants were assessed. Five SNPs in positions: −47, −20, 46, 79 and 252 of β2-AR were determined by direct DNA sequencing. RESULTS: In −47 T/T and −20 T/T patients, incubation with fenoterol resulted in decreased IgE production, whereas in −47 C/T and −47 C/C as well as in −20 C/T and −20 C/C individuals, it was enhanced. In contrast to fenoterol, budesonide-induced IgE synthesis was significantly increased in −47 T/T and −20 T/T patients as compared to −47 C/T, −47 C/C, −20 C/T and −47 C/C individuals. Polymorphisms in positions 46, 79 and 252 were not associated with fenoterol- or budesonide-modulated IgE synthesis. No differences in the distribution of IgE synthesis was seen between atopic and non-atopic individuals carrying the same alleles. CONCLUSIONS: The differential effect of β2-agonists and GCS on IgE synthesis may be associated with genetic variants of promoter region of the β2-AR gene

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Association of BRCA1 promoter methylation with rs1655505 (c.2265C>T) variants and decreased gene expression in sporadic breast cancer

OBJECTIVE: Breast cancer is the most common cancer and the main cause of cancer morbidity for women worldwide and is manifestation of abnormal genetic as well as epigenetic changes. Therefore, our aim was to study the association of BRCA1 promoter methylation with rs11655505 (c.-2265C/T) variants and gene expression in sporadic breast cancer. METHODS: Twenty-nine sporadic breast cancer tissues and 26 normal biopsies were used for this study. Genomic DNA and total RNA were extracted from paraffin-embedded tissue and SNP analysis performed. Methylation status of the BRCA1 promoter region was determined by methylation-specific PCR after sodium bisulfite modification of DNA. RESULTS: Among all clinical-pathological parameters only estrogen receptor -ve and +ve samples were significantly different for methylation status (P = 0.04). The genotypic (CC, CT and TT), allelic frequencies and methylation status had not been found to be significantly different from that of healthy controls (P = 0.67, 0.71 and 0.17, respectively). Similarly, methylated BRCA1 promoter was not found to be significantly different in different genotypes from unmethylated promoters between patients and controls. Interestingly, only heterozygous (CT) genotypes with low and normal expression of BRCA1 were significantly different for the differential expression of BRCA1 compared to controls (P = 0.004). However, in tumor samples decreased expression of gene is associated with methylated state of BRCA1 promoter [OR (95 % CI) = 25.09 (2.17-29.75); P = 0.01]. CONCLUSIONS: Our data suggest that both single nucleotide variations rs11655505 (c.-2265C/T) and the methylation status of BRCA1 are not associated significantly with the occurrence of sporadic breast cancer in studied population. However, decreased expression of gene is associated with the CT genotypes and the disease. But, in case of tumor samples, an association of methylation of the promoter to the decreased expression of BRCA1 gene suggests the possible role of methylation in gene silencing (AU)

Methylation in the p53 promoter in epithelial ovarian cancer

OBJECTIVE: Ovarian cancer is a leading cause of death from gynecologic tumors, however, the molecular and especially epigenetic events underlying this transformation are poorly understood. Promoter methylation status of tumor suppressor genes may be associated with transcriptional silencing and tumor progression. It has been shown that methylation of CpG dinucleotides located in the promoter region of p53 is associated with low expression levels of this gene. The aim of this study was to investigate promoter methylation of p53 gene in ovarian cancer by comparison with normal ovarian tissue. METHODS: To search for promoter methylation of p53 gene we used methylation-specific PCR (MSP) to compare the methylation status of 66 tissue samples of ovarian cancer with 37 control samples. RESULTS: In our study methylation specific PCR revealed p53 promoter methylation in 34 of 66 (51.5 %) of specimens with ovarian cancer. CONCLUSION: These results indicate that methylation in p53 promoter region may play an important role in carcinogenesis of ovarian cancer and could potentially be used in screening of ovarian cancer, and may have implications for future chemotherapy based on epigenetic changes (AU)

Methylation status of O6-methylguanine-DNA-methyl transferase promoter region in non-small-cell lung cancer patients with brain metastasis

Background. O6-methylguanine-DNA-methyl transferase (MGMT), a DNA repair gene, is a key enzyme for predicting the response to both radiotherapy and temozolomide in glioma patients. Data on the MGMT promoter methylation status in relation to the time to develop intracranial new metastasis or local relapse at the surgical site after brain surgery followed by radiotherapy is limited in non-smallcell lung cancer (NSCLC) patients with a single brain metastasis. Methods. All 55 patients included in this analysis were NSCLC with a single brain metastasis and had undergone brain surgery followed by radiotherapy. Genomic DNA was extracted from the brain tumour. The DNA was treated with bisulphate and a methylation-specific polymerase chain reaction was performed. Survival was compared by the status of promoter region of MGMT. Results. The time to develop intracranial new metastases or local relapse at the surgical site after treatment in patients with methylation of the MGMT promoter region was 4.0 months (N=5), while that of the patients without methylation of the MGMT promoter region was 11.5 months (N=50) (p=0.37). Conclusions. NSCLC patients with brain metastasis treated by brain surgery followed by radiotherapy may have a higher chance of relapse when the tumour has methylation of the MGMT promoter region (AU)

Análisis funcional de mutaciones en el promotor del LDLR y su relación con la hipercolesterolemia familiar / Functional analysis of LDLR promoter mutations and their relationship with familial hypercholesterolemia

Introducción La hipercolesterolemia familiar (HF) es una enfermedad autosómica dominante, causada principalmente por mutaciones en la región codificante del gen del receptor de las LDL (LDLR). Sin embargo, varias mutaciones situadas en el promotor de LDLR se han asociado con la HF. La búsqueda de mutaciones en sujetos clínicamente diagnosticados como HF reveló la presencia en la zona promotora de LDLR de 4 mutaciones nuevas en heterocigosidad. Objetivo Estudiar la funcionalidad de las 4 mutaciones nuevas en el promotor del LDLR (c.-36T>G, c.-136C>G, c.-140C>G y c.-208A>T) encontradas en España mediante el uso de la plataforma LIPOchip® en pacientes con sospecha clínica de HF. Métodos Se realizó el análisis funcional de las mutaciones mediante ensayos de retardo de la movilidad electroforética (EMSA) y transfección de promotores mutados con el gen reportero de la luciferasa en cultivos celulares de HepG2. Resultados Las mutaciones c.-136G y c.-140G localizadas en el elemento regulador R3 mostraron un cambio significativo en el patrón de afinidad por las proteínas nucleares en los EMSA. Además, estas mutaciones produjeron una reducción de la actividad del promotor LDLR del 88-93%. Las mutaciones c.-36G y c.-208T no provocaron cambios significativos ni en los experimentos EMSA ni con genes reporteros. Conclusiones Las mutaciones localizadas en el elemento R3 se asocian con HF, mientras que las que se encuentran fuera de los elementos reguladores del promotor de LDLR no son causa directa de hipercolesterolemia. Nuestros resultados revelan la importancia de realizar análisis de funcionalidad de las variantes encontradas en la región promotora de LDLR con objeto de conocer su implicación con el fenotipo HF (AU)

Introduction: Familial hypercholesterolemia (FH) is an autosomal dominant disorder mainly caused by mutations in the coding region of the LDLR gene. However, a variety of mutations within the LDLR promoter have been associated with FH. Genetic screening in persons clinically diagnosed with HF revealed the presence of four new heterozygous mutations within the promoter region. Objective: To study the functionality of the four new LDLR promoter mutations (c.-36T>G, c.-136C>G, c.-140C>G and c.-208A>T) found in Spain, using the LIPOchip® platform in patients with clinically suspected FH. Methods: The functional analysis of mutations was carried out by using electrophoretic mobility shift assays (EMSA) and luciferase reporter gene expression in HepG2 transfected cells with the mutated promoters. Results: Two mutations, c.-136G and c.-140, located within the R3 regulatory element, showed a significant change in the pattern of nuclear binding protein affinity. Moreover, these mutations reduced the residual activity of the LDLR promoter by 88-93%. However, mutations c.-36Gand c.-208T, located outside the response elements, produced no significant changes in EMSA experiments or reporter genes. Conclusions: Mutations within the R3 element are associated with FH, while those located outside the regulatory elements of the LDLR promoter are not a direct cause of FH. Our results reveal the importance of functional analysis of the new variants in the LDLR promoter region to identify their role in the FH phenotype (AU)

Una nueva mutación en el promotor del gen del receptor de las lipoproteínas de baja densidad asociada a hipercolesterolemia familiar en homocigosis y heterocigosis / A new mutation in the LDL receptor promoter gene associated with familial hypercholesterolaemia in homo and heterozygosis

La hipercolesterolemia familiar (HF) es una enfermedad hereditaria, relativamente frecuente y asociada al desarrollo de ateroesclerosis y enfermedad coronaria prematuras. En este trabajo, describimos el hallazgo de una nueva mutación (47C>A) en la región promotora del gen del receptor de las lipoproteínas de baja densidad (rLDL), principal encargado de este fenotipo. Esta mutación se identificó en una familia uruguaya con un fenotipo típico de HF, en la cual aparecen individuos heterocigotos y homocigotos para la mutación debido a la existencia de consanguinidad. El cambio nucleotídico ocurre en un sitio conservado y funcionalmente relevante del promotor; región en la que anteriormente se han descrito diversas mutaciones que provocan descensos drásticos en la actividad transcripcional del gen. No se han detectado otras variantes en las regiones analizadas del gen. Los análisis genéticos del rLDL asociados a otros genes de susceptibilidad permiten establecer un perfil genómico de riesgo cardiovascular, de aplicación muy necesaria en el tratamiento clínico de familias con HF (AU)

Familial hypercholesterolemia (FH) is an inherited disease, relatively frequent and associated with premature development of atherosclerosis and coronary heart disease. we report a family with several members affected by FH whose phenotype was presumably caused by a substitution of a cytosine by adenine in the promoter region (¿47C>A) of the LDL receptor gene (LDLR). this mutation was identified in an uruguayan family with a typical phenotype of HF in which there are hetero and homozygous individuals for the mutation, due to inbreeding. this mutation, witch has not previously been described, is located on a conserved and functionally relevant domain of the promoter. in this region several mutations have been previously described and it has been demonstrated that they cause drastic decrease in LDLR gene transcriptional activity. No other sequence variants have been detected in the sequenced LDLR gene regions. A molecular analysis of LDLR gene together with other susceptibility genes allows establishing a genomic profile of cardiovascular risk, highly applicable in the clinical management of families with FH (AU)

Patrones de hipermetilación génica en tumores ginecológicos / Promoter Hypermethylation gene patterns in gynecological tumors

Fundamento y objetivo: El silenciamiento génico mediado por la metilación aberrante de la región promotora del ácido desoxirribonucleico está implicado en la inactivación de genes involucrados en diversas vías metabólicas y se ha constituido en un marcador molecular útil en el diagnóstico, tratamiento y seguimiento de sujetos oncológicos. El objetivo de este trabajo es analizar los patrones de hipermetilación génica en mujeres con tumores ginecológicos. Sujetos y método: Se seleccionaron 115 mujeres con cánceres ginecológicos: 22 mujeres con cáncer de ovario (CO), 13 mujeres con cáncer de endometrio (CE), 11 mujeres con cáncer de cuello uterino y 69 mujeres con cáncer de mama. Mediante prueba de metilación específica por reacción en cadena de la polimerasa, se estudió el estado de metilación de los genes CDNK2A (p16), APC1A, FHIT, CDH1 y hMLH1.ResultadosLas frecuencias de metilación génica para los genes CDNK2A (p16), APC1A, FHIT, CDH1 y hMLH1 fueron del 29,2; 34; 60,4; 10,9, y 79,8%, respectivamente. El 70% de los casos presentó al menos 2 genes metilados, es decir, un índice de metilación superior a 0,4. La frecuencia de metilación más baja se observó en el CO, mientras que la frecuencia de metilación más alta se presentó en el CE. Conclusiones: Los resultados indican que la metilación aberrante de la región promotora es un acontecimiento importante en la carcinogénesis de los tumores ginecológicos y que el patrón de metilación génica se asocia a la naturaleza tumoral. Estas características particulares pueden entregar información relevante acerca de las principales vías metabólicas alteradas en cada tipo tumoral, información que sumada a estudios complementarios de pérdida de expresión o de función representa una herramienta clínica para el tratamiento adecuado de la enfermedad (AU)

Background and objective: Gene silencing mediated by the aberrant methylation of the promoter region of DNA is involved in the inactivation of genes implicated in various metabolic pathways. Such a gene hypermethylation has become a useful molecular marker for the diagnosis, treatment and follow-up of cancer patients. Our objective is to analyze the patterns of gene hypermethylation in patients with gynecological tumors. Patients and methods: We selected 115 patients with gynecological cancers: 22 ovarian; 13 endometrial, 11 cervical-uterine and 69 breast cancers. By testing methylation-specific PCR, we studied the methylation status of genes CDNK2A (p16), APC1A, FHIT, CDH1 and hMLH1.ResultsThe frequencies of gene methylation in genes p16, APC1A, FHIT, hMLH1 and CDH1 were 29.2%, 34%, 60.4%, 10.9% and 79.8%, respectively. 70% of cases showed at least two methylated genes, which means a rate of methylation >0.4. The lowest frequency of methylation was seen in ovarian cancer, while the highest one was observed in endometrial cancer. Conclusions: The results indicate that the aberrant methylation of the promoter region is an important event in carcinogenesis of gynecological tumors and that the pattern of gene methylation is associated with the nature of the tumor. These particular characteristics can deliver relevant information on the major metabolic pathways altered in each tumor type. In addition to complementary studies (ie, loss of expression and/or function), this represents a clinical tool for the proper management of the disease (AU)

Polimorfismos genéticos en la catecol-Ometiltransferasa y riesgo de esquizofrenia en población española / Effect of polymorphisms of the cathecol-O-methyltransferase on schizophrenia risk in a Spanish population

FUNDAMENTO Y OBJETIVO: Uno de los genes susceptibles de ser considerado candidato para los estudiosde asociación con esquizofrenia es, a priori, el de la catecol-O-metiltransferasa (COMT).La variante genética más estudiada (G158A o rs4680) es funcional. Además, se ha propuestoque las variantes genéticas que afectan al promotor P2 podrían producir cambios en los valoresde COMT en el cerebro. Recientemente, se ha relacionado una variante en este promotor(–278A/G o rs1800706) con los trastornos psicóticos. El objetivo de este trabajo es estudiar sipolimorfismos genéticos del gen COMT (G158A) y su promotor (–278A/G) influyen en la susceptibilidada la esquizofrenia en la población española.PACIENTES Y MÉTODO: Participaron en este estudio de asociación 243 pacientes diagnosticados deesquizofrenia y trastornos relacionados según los criterios del DSM-IV (Diagnostic and StatisticalManual of Mental Disorders, cuarta edición) y 291 sujetos de un grupo control de base hospitalaria.RESULTADOS: No se encontraron diferencias significativas entre casos y controles para las frecuenciasalélicas de los polimorfismos estudiados, ni tampoco cuando se analizaron los genotiposdel polimorfismo COMT G158A. Sin embargo, los individuos heterocigotos para el polimorfismoCOMT –278A/G presentaban una reducción del 60% en el riesgo de presentaresquizofrenia (odds ratio = 0,4, intervalo de confianza del 95%, 0,2-0,8, p = 0,009).CONCLUSIONES: Los datos de este estudio exploratorio están de acuerdo con resultados recientesen este campo, que indican una menor influencia del polimorfismo clásico COMT G158A en elriesgo de esquizofrenia y una mayor importancia de los polimorfismos que afectan al promotorP2 del gen, como -278A/G

BACKGROUND AND OBJECTIVE: Cathecol-O-methyl transferase (COMT) is one of the most plausiblesusceptibility genes of schizophrenia risk. The main genetic variant (G158A or rs4680) studiedis functional. It has been shown that G-A transition at COMT codon 158 makes COMT morethermolabile and less active at physiological temperature. Genetic variants in the P2 promoterhave been suggested to cause alterations in brain COMT protein levels. A variant in the P2 promoter(–278A/G or rs1800706) has recently been associated with psychotic disorders. We studiedwhether polymorphisms in COMT (G158A, –278A/G) are risk factors for schizophrenia in aSpanish population.PATIENTS AND METHOD: 243 subjects diagnosed of schizophrenia and related disorders followingthe DSM-IV criteria and 291 hospital-based controls participated in an association study.RESULTS: The heterozygotes for the COMT –278A/G polymorphism showed a 60% reduction inthe schizophrenia risk (p = 0.009). No significant differences were observed between the otherCOMT genotypes or haplotypes in cases and controls.CONCLUSIONS: Our results suggest that the COMT –278A/G polymorphism may have a role inschizophrenia. The results are in agreement with recent findings in this field that indicate a minorinfluence of COMT G158A on schizophrenia risk and a greater importance of polymorphismsin the P2 promoter regions of COMT, such as –278A/G

Characterization of the promoter region of ftsZ from Corynebacterium glutamicum and controlled overexpression of FtsZ

Of the five promoters detected for the ftsZ gene in Corynebacterium glutamicum, three were located within the coding region of the upstream ftsQ gene and two within the intergenic ftsQ-ftsZ region. The most distant ftsZ promoter showed activity in Escherichia coli and controlled high-level transcriptional expression of ftsZ in C. glutamicum. Quantitative Western blotting showed that all five promoters were active during the exponential growth phase and down-regulated during stationary phase. This tightly controlled expression of ftsZ in C. glutamicum indicated that small changes in the amount of FtsZ protein strongly affect bacterial cell viability. The controlled overexpression of ftsZ in C. glutamicum, using the promoter of the gntK gene (PgntK), resulted in approximately 5-fold overproduction of FtsZ, an increase in cell diameter, and a highly variable localization of the protein as spirals or tangles throughout the cell. These results suggest that the intracellular concentration of FtsZ is critical for productive septum formation in C. glutamicum. Our observations provide insight into the mechanisms used by the coryneform group, which lacks actin homologs and many regulators of cell division, to control cell morphology (AU)

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Hipermetilación del promotor del gen reparador hMLH1 en la patogenia del carcinoma de células renales esporádico / Promoter hypermethylation status of the mismatch repair gene hMLH1 in patients with sporadic renal cell carcinoma

Fundamento y objetivo: La metilación de los islotes CpG (secuencias del genoma ricas en guanina y citosina) presentes en las regiones promotoras constituye la forma de inactivación epigenética más común y es una alteración en el mecanismo de regulación de los genes que no requiere cambios en la secuencia del ADN. Se ha descrito hipermetilación del promotor del gen hMLH1 en algunas líneas celulares procedentes de carcinoma de células renales (CCR). Nuestro objetivo ha sido determinar la existencia de hipermetilación en el promotor del gen hMLH1 en muestras de ADN tumoral de pacientes con CCR esporádico. Material y método: Se recogieron consecutivamente 65 muestras de tejido tumoral procedente de pacientes diagnosticados de CCR. Tras la obtención y purificación del ADN se procedió a su digestión con las enzimas de restricción HpaII y MspI, seguido de amplificación mediante reacción en cadena de la polimerasa de 3 regiones del promotor del gen hMLH1, electroforesis en gel de agarosa y análisis densitométrico de las bandas amplificadas. Resultados: La edad media de los pacientes fue de 63,7 años. El tipo celular más frecuente fue el carcinoma de células claras (67,7%). Un 73,9% de los tumores se diagnosticaron en estadios inferiores a pT2, un 9,3% tenían afectación ganglionar y un 20%, metástasis a distancia. No se detectó hipermetilación somática en la región promotora del gen hMLH1 en ninguno de los pacientes estudiados. Conclusiones: La hipermetilación del promotor del gen hMLH1 no parece intervenir en la patogenia del CCR esporádico, y es necesario analizar la existencia de otro tipo de mutaciones, inestabilidad de microsatélites y/o pérdida de heterocigosis para determinar el posible papel de este gen en la patogenia del CCR esporádico

Background and objective: Epigenetic inactivation is a gene function abnormality that produces no changes in the DNA sequence, with the most frequent epigenetic alteration being hypermethylation of CpG islands in the promoter regions of the genes. Based on recent indications of a potential relationship between mismatch repair genes and renal cell carcinoma (RCC), we were interested in investigating the existence of promoter hypermethylation of the hMLH1 gene in tumor DNA samples from patients with sporadic RCC. Material and method: Sixty-five tumor tissue specimens were collected consecutively. The DNA was first obtained and purified, then digested with the restriction enzymes Hpa II and Msp I, followed by polimerase chain reaction amplification of 3 promoter regions of the hMLH1 gene, agarose gel electrophoresis, and densitometric analysis of the images of the amplified bands. Results: Mean patient age was 63.7 years. The most frequent cell type was clear cell carcinoma (67.7%). 73.9% of tumors were diagnosed in stages below pT2, 9.3% had gland involvement and 20%, distant metastasis. No somatic hypermethylation was detected in the promoter region of the hMLH1 gene in any of the patients studied. Conclusions: Our data indicate that promoter hypermethylation of the hMLH1 gene is not implicated in the pathogenesis of sporadic RCC, and therefore the existence of another type of mutation, microsatellite instability and/or loss of heterozygosity should be examined to determine the possible role of this gene in sporadic RCC

Frecuencia y distribución de las variantes alélicas del gen de la tiopurina S-metiltransferasa en distintos grupos étnicos españoles / Frequency of thiopurine S-methyltransferase alleles in different ethnic groups living in Spain

Fundamento y objetivo: La tiopurina S-metiltransferasa (TPMT) participa en el metabolismo de diversos fármacos. La presencia de diferentes alelos del gen de la TPMT se relaciona con la actividad de dicha enzima. La existencia de un número variable de repeticiones en tándem en la región promotora del gen de la TPMT parece modular la actividad enzimática. En este trabajo se estudian la frecuencia y la distribución de las variantes alélicas del gen de la TPMT en distintos grupos étnicos españoles. Sujetos y método: Se han analizado 4 variantes alélicas del gen de la TPMT y se define el genotipo en la región promotora del gen en población española (n = 138) y en 2 grupos étnicos diferenciados residentes en España: población gitana (n = 95) y población vasca (n = 51). Resultados: En el grupo de 138 donantes de sangre españoles se encontraron 13 heterocigotos de un alelo TPMT mutado (*3A, *3B, *3C), un homocigoto TPMT*3B y un caso de doble heterocigotia TPMT*3A/ TPMT*3B. En la población de origen vasco (n = 51) se detectaron 3 portadores del alelo TPMT*3A y un sujeto heterocigoto para el alelo TPMT*3B. El estudio de la población gitana (n = 95) mostró un individuo con un alelo TPMT*3A y 3 individuos heterocigotos compuestos TPMT*3A/TPMT*3B. El alelo mutante más prevalente fue el TMPT*3A. En referencia al número de repeticiones en tándem de la región 5' del gen de la TPMT, los alelos con 4 o 5 repeticiones representan el 96,4% de los cromosomas en el grupo de control de población española. Esta cifra desciende hasta el 75% en los vascos y hasta un 62% en el grupo de población gitana. En estos últimos, el 37% de los alelos contienen más de 5 repeticiones en la región promotora del gen. Conclusiones: Las frecuencias alélicas del gen de la TPMT observadas en los 3 grupos estudiados han sido similares a las descritas en otras poblaciones caucásicas

Background and objective: Thiopurine S-methyltransferase (TPMT) metabolizes thiopurine drugs regulating their cytotoxicity and clinical response. TPMT activity is inherited as an autosomal recessive trait and several mutations in the TPMT gene have been identified which correlate with a low activity phenotype. A variable number of tandem repeat within the TPMT promoter has been reported to modulate the levels of this enzyme activity. The allelic variants of the TPMT gene were analyzed in ethnic groups living in Spain. Subjects and method: The frequency of 4 allelic variants of the TPMT gene as well as the genotype in the promoter region were analyzed in 138 Spanish blood donors, 95 gypsies and 51 Basque subjects. Results: In the group of 138 blood donors, we identified: 13 carriers of a mutated TPMT allele (*3A, *3B, *3C), one homozygous TPMT*3B and a compound heterozygote (TPMT*3A/TPMT*3B). In the Basque group, 3 subjects were TPMT*3A carriers and one case was a TPMT*3B heterozygote. In the gypsy group one subject carried a TPMT*3A allele and 3 were compound heterozygotes TPMT*3A/TPMT*3B. The TMPT*3A was the most frequent mutant alelle. As for the polymorphic tandem repeat in the 5' flanking region of the TPMT gene, alleles with 4 or 5 repeats made up the vast majority (96%) of the chromosomes in the control group of Spanish subjects. This figure decreased to 75% in Basques and to 62% in gypsies, in whom 37% of the alleles contained more than 5 tandem repeats. Conclusions: The frequencies of the mutant TPMT alleles observed in the 3 groups are similar to those reported in Caucasian populations

Polimorfismos de nucleótido único (SNPs) en la región promotora CDH1 en cáncer gástrico familiar / Single nucleotide polymorphisms (SNPs) at CDH1 promoter region in familial gastric cancer

Introducción: el cáncer gástrico es la neoplasia más frecuentedel tracto gastrointestinal en México y la proporción de pacientesmenores de 40 años es una de las más altas reportadas en la literaturamundial. Recientemente se han identificado en el InstitutoNacional de Ciencias Médicas y Nutrición varias familias con cáncergástrico difuso familiar. Múltiples mutaciones germinales delgene de E-cadherina (CHD1) han sido descritas en relación al desarrollode cáncer gástrico difuso hereditario en pacientes jóvenes.Métodos: la secuencia codificadora completa exones 1 al 16y la región promotora de CDH1 fueron amplificadas mediantereacción en cadena de la polimerasa en muestras de sangre periféricade dos pacientes con diagnósticos de cáncer gástrico deaparición temprana familiar.Resultados: en ninguno de los 2 pacientes se detectaron mutacionesgerminales inactivadoras de CDH1. Se encontraron polimorfismosde nucleotido único C→A en la región promotora deCDH1 en la posición –160 en ambos pacientes.Conclusiones: el polimorfismo –160 C→A confiere teóricamenteun aumento en el riesgo de desarrollar cáncer gástrico difuso.Los miembros de las familias presentan un riesgo mayor paracáncer gástrico difuso al igual que otras neoplasias. No existe actualmenteevidencia suficiente para considerar al polimorfismo–160 C→A como un factor etiológico determinante de cáncergástrico difuso debido a que la frecuencia y tipo de alteraciones enel gen CDH1 en población mexicana se desconocen. Será necesariollevar a cabo estudios epidemiológicos en población mexicanaque determinen la influencia de diversas alteraciones genéticasen la génesis de esta neoplasia

Introduction: gastric cancer is the most frequent gastrointestinalmalignancy in Mexico and the proportion of patientsyounger than 40 years is one of the highest reported in theworld literature. Recently several families with familial diffusegastric cancer have been identified at the National Institute ofMedical Sciences and Nutrition. Germline mutations in theE-cadherin gene (CHD1) have been described that result in thedevelopment of diffuse hereditary gastric cancer in young patients.Methods: the complete coding sequence at exons 1 to 16 andthe promoter region of CDH1 was amplified by polymerase chainreaction in peripheral blood samples of two patients with early onsetfamilial diffuse gastric cancer.Results: no germline inactivating mutations of CHD1were found on either patient. Single nucleotide polymorphisms-160 C→A were detected in the promoter region ofCDH1 in both patients.Conclusions: the polymorphism -160 C→Α theoreticallyconfers an increased risk of developing diffuse gastric cancer.The relatives of these patients may an increased risk of gastriccancer among other tumors. There is presently not enough evidenceto consider the -160 C→Α polymorphism an etiologicfactor of diffuse gastric cancer in these patients since the frequencyand type of genetic alterations of CDH1 are largely unknownin the Mexican population. It will be necessary to conductepidemiologic studies in the Mexican population todetermine the influence that genetic alterations have on thegenesis of diffuse gastric carcinoma

Fuerte modulación del sexo sobre el riesgo conferido por el gen de la apolipoproteína E para la enfermedad de Alzheimer en la población de las Islas Canarias, España / Gender has a strong modulating effect on the risk of Alzheimer's disease conferred by the apolipoprotein e gene in the population of the canary islands, Spain

Objetivos. En la mayoría de las poblaciones estudiadas se ha encontrado que el gen de la apolipoproteína E (ApoE) es un factor de riesgo para la enfermedad de Alzheimer (EA). El objetivo del presente trabajo es el estudio de los polimorfismos de dicho gen, tanto de las variantes exónicas como los polimorfismos de promotor, en nuestra población canaria. Sujetos y métodos. Hemos analizado, por medio de técnicas de PCR-RFLP, tanto las variantes exónicas como tres de los polimorfismos de promotor más comunes del gen de la ApoE, sobre el ADN de 131 pacientes diagnosticados clínicamente de probable EA, según criterios NINCS-ADRDA, y 85 controles sin déficit cognitivo medido por el test de CAMCOG. Resultados. Hemos encontrado que las variantes alélicas exónicas del gen de la ApoE se relacionan fuertemente con la EA, presentan un claro efecto de dosis sobre la susceptibilidad a la enfermedad, mientras que no muestran ninguna asociación con la enfermedad las variantes de promotor. En nuestra muestra analizada, el gen de la ApoE no parece influir en la edad de presentación de la enfermedad, mientras que el sexo de los pacientes confiere características de susceptibilidad distintivas. Conclusión. En nuestra población, el gen de la ApoE se relaciona con la EA, y está condicionado por una fuerte modulación del sexo de los pacientes (AU)

Objectives. Apolipoprotein E (ApoE) gen has been found to confer risk for Alzheimer disease in every population studied. We are interested in analyzed the exonic variants and the promoter polymorphisms in our Canary population. Subjects and methods. By means of PCR-RFLP analysis of DNA from patients (NINCS-ADRDA criteria) and controls (cognitive state CAMCOG test measured) we analyzed the known exonic and promoter polymorphism of ApoE gen. Results. We have found an association of Alzheimer disease risk based on exonic variants of ApoE gen, with a clear cut dose-effect on susceptibility and no risk conferred by the promoter polymorphisms. Age at onset are not affected by variants of ApoE gen, and patients gender strongly modulate the disease susceptibility. Conclusion. We have found in our Canary population an association between Alzheimer disease with exonic variants of ApoE gen with a strong modulation by the patients gender (AU)

Genetic variants of Fc RI and Il-4 and atopy in a Polish population

Background: Atopy results from the interaction between genetic and environmental factors. The aim of our study was to clarify the association between the FcRIint2 polymorphic variant, the Glu237Gly mutation in exon 7 of FcεRIβ and (-590 C/T) Il-4 gene promoter polymorphism with atopy in a randomized Polish sample. Subjects and methods: Unrelated subjects aged 18-45 years who were residents of an urban area (Lodz, Poland) were included in the study: 98 patients with asthma and/or allergic rhinitis, and 87 non-atopic, non-asthmatic controls. We used common criteria for atopy and asthma. Atopic status was determined by positive skin prick tests (SPT) and IgE levels. The severity of asthma was assessed in spirometric measurements; SPTs to house dust mite (HDM) and mixed grass pollen (MGP) were performed. Total and specific IgE were measured in each subject. Genotypic analysis was performed by PCR for FcRIint2 and (­590 C/T) Il-4 gene promoter polymorphism and ARMS-PCR was performed for the Glu237Gly mutation. Results: We found a statistically significant association between atopy and FcRIint2 variant polymorphism (OR = 2.96), a correlation between positive skin prick tests to MGP and raised MGP-specific IgE concentrations in patients bearing this variant (OR = 4.0). We did not observe that the FcRIint2 variant was associated with positive SPTs to HDM or high levels of HDM-specific IgE (OR = 1.0). The intronic variant of FcεRIβ was strongly correlated with elevated total serum IgE (OR = 4.74). No statistically significant association was found between atopy and the Glu237Gly mutation of FcεRIβ (OR = 1.36) or (-590 C/T) Il-4 gene promoter polymorphism (OR = 0.88). Conclusions: The results suggest that FcRIint2 polymorphism is related to atopy and may influence its development (AU)

Información básica: Resultados de atopia de la interacción de factores genéticos y ambientales. El objetivo de nuestro estudio era esclarecer la asociación entre la Fc€RIBeta variante polimorfa de Fc int2, la mutación Glu237Gly en el exón 7 de Fc€RIBeta y el polimorfismo del promotor génico (-590 C/T) Il-4 con atopia en una muestra polaca aleatorizada. Sujetos y métodos: Se incluyó en el estudio a sujetos de 18-45 años no emparentados, residentes en el área urbana (Lodz, Polonia): 98 pacientes con asma, rinitis alérgica o ambas y 87 controles no asmáticos y no atópicos. Utilizamos los criterios habituales para la atopia y el asma. El estado atópico se determinó por pruebas de punción cutánea positivas (spts) y las concentraciones de IgE. La gravedad del asma se evaluó con mediciones espirométricas; se realizaron spts frente a ácaros del polvo doméstico (hdm) y mezcla de polen de gramíneas (mgp). Se cuantificaron en cada sujeto los valores de IgE total y específica. Se efectuó un análisis de genotipo mediante PCR para Fc€RIBetaint2 y el polimorfismo del promotor génico (-590 C/T) Il-4, y ARMS-PCR para la mutación Glu237Gly. Resultados: Observamos una asociación estadísticamente significativa entre la atopia y el polimorfismo variante FcRIint2 (razón de posibilidades (RP = 2,96) y una correlación entre las pruebas de punción cutánea positivas frente a mgp y el aumento de las concentraciones de IgE específica para mgp en pacientes que albergaban la variante (RP = 4,0). No observamos que la variante FcRIint2 se asociase a spts positivas frente a hdm ni a concentraciones elevadas de IgE para hdm (RP = 1,0). La variante intrónica de Fc€RIBeta guardó una estrecha relación con la elevación de la IgE sérica total (RP = 4,74). No hubo una asociación estadísticamente significativa entre la atopia y la mutación Glu237Gly de Fc€RIBeta (RP = 1,36) o el polimorfismo del promotor génico (-590 C/T) Il-4 (RP = 0,88). Conclusiones: Los resultados indican que el polimorfismo de Fc€RIBeta int2 se relaciona con la atopia y puede influir en su desarrollo (AU)