Understanding the molecular profiling of diffuse gliomas classification: A brief overview.

Background: Gliomas represent almost 30% of all primary brain tumors and account for 80% of malignant primary ones. In the last two decades, significant progress has been made in understanding gliomas' molecular origin and development. These advancements have demonstrated a remarkable improvement in classification systems based on mutational markers, which contribute paramount information in addition to traditional histology-based classification. Methods: We performed a narrative review of the literature including each molecular marker described for adult diffuse gliomas used in the World Health Organization (WHO) central nervous system 5. Results: The 2021 WHO classification of diffuse gliomas encompasses many molecular aspects considered in the latest proposed hallmarks of cancer. The outcome of patients with diffuse gliomas relies on their molecular behavior and consequently, to determine clinical outcomes for these patients, molecular profiling should be mandatory. At least, the following molecular markers are necessary for the current most accurate classification of these tumors: (1) isocitrate dehydrogenase (IDH) IDH-1 mutation, (2) 1p/19q codeletion, (3) cyclin-dependent kinase inhibitor 2A/B deletion, (4) telomerase reverse transcriptase promoter mutation, (5) α-thalassemia/ mental retardation syndrome X-linked loss, (6) epidermal growth factor receptor amplification, and (7) tumor protein P53 mutation. These molecular markers have allowed the differentiation of multiple variations of the same disease, including the differentiation of distinct molecular Grade 4 gliomas. This could imply different clinical outcomes and possibly impact targeted therapies in the years to come. Conclusion: Physicians face different challenging scenarios according to the clinical features of patients with gliomas. In addition to the current advances in clinical decision-making, including radiological and surgical techniques, understanding the disease's molecular pathogenesis is paramount to improving the benefits of its clinical treatments. This review aims to describe straightforwardly the most remarkable aspects of the molecular pathogenesis of diffuse gliomas.

Coexpression network analysis identified lncRNAs-mRNAs with potential relevance in African ancestry prostate cancer.

AIM: This study aims to investigate similarities and differences using lncRNA and mRNA coexpression network analysis in African ancestry (AA) and European ancestry (EA) among prostate cancer (PCa) patients. METHODS: We performed weighted gene coexpression network analysis of the expression from 49 of AA and 49 of EA to identify lncRNAs-mRNAs. RESULTS: 27 lncRNAs and 36 mRNAs were highly expressed in patients of AA. Two mRNAs and their antisense lncRNAs were expressed. Additionally, seven mRNAs were DE or coexpressed and had an impact on survival. CONCLUSION: We present a list of lncRNAs and mRNAs that were DE and coexpressed when comparing patients of AA and EA, and these data are a resource for future studies to understand the role of lncRNAs.

Generation, characterization, and drug sensitivities of 12 patient-derived IDH1-mutant glioma cell cultures.

BACKGROUND: Mutations of the isocitrate dehydrogenase (IDH) gene occur in over 80% of low-grade gliomas and secondary glioblastomas. Despite considerable efforts, endogenous in vitro IDH-mutated glioma models remain scarce. Availability of these models is key for the development of new therapeutic interventions. METHODS: Cell cultures were established from fresh tumor material and expanded in serum-free culture media. D-2-Hydroxyglutarate levels were determined by mass spectrometry. Genomic and transcriptomic profiling were carried out on the Illumina Novaseq platform, methylation profiling was performed with the Infinium MethylationEpic BeadChip array. Mitochondrial respiration was measured with the Seahorse XF24 Analyzer. Drug screens were performed with an NIH FDA-approved anti-cancer drug set and two IDH-mutant specific inhibitors. RESULTS: A set of twelve patient-derived IDHmt cell cultures was established. We confirmed high concordance in driver mutations, copy numbers and methylation profiles between the tumors and derived cultures. Homozygous deletion of CDKN2A/B was observed in all cultures. IDH-mutant cultures had lower mitochondrial reserve capacity. IDH-mutant specific inhibitors did not affect cell viability or global gene expression. Screening of 107 FDA-approved anti-cancer drugs identified nine compounds with potent activity against IDHmt gliomas, including three compounds with favorable pharmacokinetic characteristics for CNS penetration: teniposide, omacetaxine mepesuccinate, and marizomib. CONCLUSIONS: Our twelve IDH-mutant cell cultures show high similarity to the parental tissues and offer a unique tool to study the biology and drug sensitivities of high-grade IDHmt gliomas in vitro. Our drug screening studies reveal lack of sensitivity to IDHmt inhibitors, but sensitivity to a set of nine available anti-cancer agents.

Prevalence and Demographic Characteristics of Prostate Cancer Patients in Colombia: data from the National Health Registry from 2015 to 2019 / Prevalencia y características demográficas de pacientes con cáncer de próstata en Colombia: datos del Registro de Salud Nacional de 2015 a 2019

Background and Objective Prostate cancer is a multifactorial disease and is among the top five causes of death in men worldwide. The Colombian Ministry of Health has adopted the Integrated Information System on Social Protection (Sistema Integrado de Información de la Protección Social, SISPRO, by its Spanish acronym) registry to collect comprehensive information from the Colombian health system. The system provides close to universal coverage (around 95%). We aimed to establish the prevalence of prostate cancer in Colombia and to describe its demographics, based on data provided by SISPRO, openly available for scientific analysis. Methods Using the SISPRO data from 2015 through 2019, we analyzed the prevalence and demographic characteristics of patients diagnosed with prostate cancer. Results We identified a total of 43,862 patients with prostate cancer in the 5-year period and estimated a prevalence of 4.54 cases per 1,000 habitants, using as denominator males over 35 years old. We calculated a prevalence of early-onset prostate cancer (i.e., 35­54 years) of 0.14 per 1,000 habitants (791 cases in 5 years). The highest prevalence was observed in patients>80 years (33.45 per 1,000 habitants). The departments with the highest prevalence were Bogotá, Valle del Cauca, Risaralda, and Boyacá, and the region with the lowest prevalence was Amazonas.

Antecedentes y Objetivo El cáncer de próstata es una enfermedad multifactorial, y se encuentra entre las cinco principales causas de muerte en hombres a nivel mundial. El Ministerio de Salud de Colombia ha adoptado el Sistema Integrado de Información de la Protección Social (SISPRO) para la recopilación de la información integral del sistema de salud colombiano. El sistema proporciona una cobertura casi universal (alrededor del 95%). El objetivo de este estudio fue establecer la prevalencia del cáncer de próstata en Colombia y describir su demografía, con base en los datos proporcionados por el SISPRO, disponibles de forma abierta para el análisis científico. Métodos Utilizando los datos del SISPRO de 2015 a 2019, se analizaron la prevalencia y las características demográficas de los pacientes diagnosticados con cáncer de próstata. Resultados Se identificó un total de 43,862 pacientes con cáncer de próstata en el período de 5 años, con una prevalencia de 4,54 casos por cada mil habitantes, utilizando como denominador hombres mayores de 35 años. La prevalencia de cáncer de próstata de inicio temprano (es decir, paciente de 35 a 54 años) fue de 0.14 por mil habitantes (791 casos en 5 años). La mayor prevalencia se observó en pacientes > 80 años (33,45 por mil habitantes). Los departamentos con mayor prevalencia fueron Bogotá, Valle del Cauca, Risaralda, y Boyacá. Y la región con menor prevalencia fue Amazonas. Conclusión Describimos la prevalencia y la demografía del cáncer de próstata y el cáncer de próstata de inicio temprano en Colombia utilizando la base de datos del sistema nacional de salud. Observamos una distribución desigual de la prevalencia entre las regiones, que puede estar relacionada con factores raciales, ambientales, o de acceso, que justifican más estudios.

Optic nerve coloboma as extension of the phenotype of 22q11.23 duplication syndrome: a case report.

BACKGROUND: 22q11.2 duplication syndrome (Dup22q11.2) has reduced penetrance and variable expressivity. Those affected may have intellectual disabilities, dysmorphic facial features, and ocular alterations such as ptosis, hypertelorism, nystagmus, and chorioretinal coloboma. The prevalence of this syndrome is unknown, there are only approximately 100 cases reported. However Dup22q11.2 should have a similar prevalence of DiGeorge syndrome (1 in each 4000 new-borns), in which the same chromosomal region that is duplicated in Dup22q11.2 is deleted. CASE PRESENTATION: We report a patient with intellectual disability, psychomotor development delay, hearing loss with disyllable pronunciation only, hyperactivity, self-harm, hetero-aggressive behaviour, facial dysmorphism, left facial paralysis, post-axial polydactyly, and for the first time in patients with Dup22q11.2, optic nerve coloboma and dysplasia in optic nerve. Array comparative genomic hybridization showed a 22q11.23 duplication of 1.306 million base pairs. CONCLUSIONS: New ocular findings in Dup22q11.2 syndrome, such as coloboma and dysplasia in the optic nerve, are reported here, contributing to the phenotypic characterization of a rarely diagnosed genetic syndrome. A complete characterization of the phenotype is necessary to increase the rate of clinical suspicion and then the genetic diagnostic. In addition, through bioinformatics analysis of the genes mapped to the 22q11.2 region, it is proposed that deregulation of the SPECC1L gene could be implicated in the development of ocular coloboma.

Identification of candidate miRNAs in early-onset and late-onset prostate cancer by network analysis.

The incidence of patients under 55 years old diagnosed with Prostate Cancer (EO-PCa) has increased during recent years. The molecular biology of PCa cancer in this group of patients remains unclear. Here, we applied weighted gene coexpression network analysis of the expression of miRNAs from 24 EO-PCa patients (38-45 years) and 25 late-onset PCa patients (LO-PCa, 71-74 years) to identify key miRNAs in EO-PCa patients. In total, 69 differentially expressed miRNAs were identified. Specifically, 26 and 14 miRNAs were exclusively deregulated in young and elderly patients, respectively, and 29 miRNAs were shared. We identified 20 hub miRNAs for the network built for EO-PCa. Six of these hub miRNAs exhibited prognostic significance in relapse-free or overall survival. Additionally, two of the hub miRNAs were coexpressed with mRNAs of genes previously identified as deregulated in EO-PCa and in the most aggressive forms of PCa in African-American patients compared with Caucasian patients. These genes are involved in activation of immune response pathways, increased rates of metastasis and poor prognosis in PCa patients. In conclusion, our analysis identified miRNAs that are potentially important in the molecular pathology of EO-PCa. These genes may serve as biomarkers in EO-PCa and as possible therapeutic targets.

DNA damage and transcription stress cause ATP-mediated redesign of metabolism and potentiation of anti-oxidant buffering.

Accumulation of DNA lesions causing transcription stress is associated with natural and accelerated aging and culminates with profound metabolic alterations. Our understanding of the mechanisms governing metabolic redesign upon genomic instability, however, is highly rudimentary. Using Ercc1-defective mice and Xpg knock-out mice, we demonstrate that combined defects in transcription-coupled DNA repair (TCR) and in nucleotide excision repair (NER) directly affect bioenergetics due to declined transcription, leading to increased ATP levels. This in turn inhibits glycolysis allosterically and favors glucose rerouting through the pentose phosphate shunt, eventually enhancing production of NADPH-reducing equivalents. In NER/TCR-defective mutants, augmented NADPH is not counterbalanced by increased production of pro-oxidants and thus pentose phosphate potentiation culminates in an over-reduced redox state. Skin fibroblasts from the TCR disease Cockayne syndrome confirm results in animal models. Overall, these findings unravel a mechanism connecting DNA damage and transcriptional stress to metabolic redesign and protective antioxidant defenses.

Co-Expression Network Analysis Identifies Possible Hub Genes in Aging of the Human Prefrontal Cortex / Análisis de redes de coexpresión identifica posibles genes clave en el envejecimiento de la corteza prefrontal humana / Análise de redes de co-expressão identifica possíveis genes chave no envelhecimento do córtex pré-frontal humano

Abstract Introduction : Aging is the main risk factor for the development of chronic diseases such as cancer, diabetes, Parkinson's disease, and Alzheimer's disease. The central nervous system is particularly susceptible to progressive functional deterioration associated with age, among the brain regions the prefrontal cortex (PFC) has one of the highest involvements. Transcriptomics studies of this brain region have identified the decrease in synaptic function and activation of neuroglia cells as fundamental characteristics of the aging process. The aim of this study was to identify hub genes in the transcriptomic deregulation in the PFC aging to advance in the knowledge of this process. Materials and methods : A gene co-expression analysis was carried out for 45 people 60 to 80 years old compared with 38 people 20 to 40 years old. The networks were visualized and analyzed using Cytoscape; citoHubba was used to determine which genes had the best topological characteristics in the co-expression networks. Results : Five genes with high topological characteristics were identified. Four of them -HPCA, CACNG3, CA10, PLPPR4- were repressed and one was over-expressed -CRYAB-. Conclusion: The four repressed genes are expressed preferentially in neurons and regulate the synaptic function and the neuronal plasticity, while the overexpressed gene is typical of glial cells and is expressed as a response to neuronal damage, facilitating myelination and neuronal regeneration.

Resumen Introducción : el envejecimiento es el principal factor de riesgo para el desarrollo de enfermedades crónicas como el cáncer, la diabetes, el Parkinson y el Alzheimer. El sistema nervioso central es particularmente susceptible al deterioro funcional progresivo asociado con la edad, entre las regiones cerebrales con mayor compromiso se encuentra la corteza prefrontal (CPF). Estudios de transcriptómica de esta región han identificado como características fundamentales del proceso de envejecimiento la disminución de la función sináptica y la activación de las células de la neuroglia. No es claro cuáles son las causas iniciales, ni los mecanismos moleculares subyacentes a estas alteraciones. El objetivo de este estudio fue identificar genes clave en la desregulación transcriptómica en el envejecimiento de la CPF para avanzar en el conocimiento de este proceso. Materiales y métodos : se hizo un análisis de coexpresión de genes de los transcriptomas de 45 personas entre 60 y 80 años con el de 38 personas entre 20 y 40 años. Las redes fueron visualizadas y analizadas usando Cytoscape, se usó citoHubba para determinar qué genes tenían las mejores características topológicas en las redes de coexpresión. Resultados : se identificaron cinco genes con características topológicas altas. Cuatro de ellos -HPCA, CACNG3, CA10, PLPPR4- reprimidos y uno sobreexpresado -CRYAB-. Conclusión : los cuatro genes reprimidos se expresan preferencialmente en neuronas y regulan la función sináptica y la plasticidad neuronal, mientras el gen sobreexpresado es típico de células de la glía y se expresa como respuesta a daño neuronal facilitando la mielinización y la regeneración neuronal.

Resumo Introdução : o envelhecimento é o principal fator de risco pra o desenvolvimento de doenças crónicas como o câncer, a diabetes, o Parkinson e o Alzheimer. O sistema nervoso central é particularmente susceptível ao deterioro funcional progressivo associado à idade, uma das regiões do cérebro com maior compromisso é o pré-frontal (CPF). Estudos de transcritoma desta região têm identificado como características fundamentais do processo de envelhecimento a diminuição da função sináptica e ativação das células da neuroglia. Não é claro quais são as causas iniciais, nem os mecanismos moleculares subjacentes a estas alterações. O objetivo deste estudo foi identificar genes chave na desregulação transcritoma no envelhecimento da CPF para avançar no conhecimento deste processo. Materiais e métodos : se fez uma análise de co-expressão de genes dos transcritomas de 45 pessoas entre 60 e 80 anos com o de 38 pessoas entre 20 e 40 anos. As redes foram visualizadas e analisadas usando Cytoscape, usou-se citoHubba para determinar que genes tinham as melhores características topológicas nas redes de co-expressão. Resultados : identificaram-se cinco genes com características topológicas altas. Quatro deles -HPCA, CACNG3, CA10, PLPPR4- reprimidos e um superexpresso -CRYAB-. Conclusão : os quatro genes reprimidos se expressam preferencialmente em neurônios e regulam a função sináptica e plasticidade neuronal, enquanto o gene superexpresso é típico de células da glia e se expressa como resposta ao dano neuronal facilitado a mielinização e a regeneração neuronal.

Peripheral mitochondrial function correlates with clinical severity in idiopathic Parkinson's disease.

BACKGROUND: Parkinson's disease is an intractable disorder with heterogeneous clinical presentation that may reflect different underlying pathogenic mechanisms. Surrogate indicators of pathogenic processes correlating with clinical measures may assist in better patient stratification. Mitochondrial function, which is impaired in and central to PD pathogenesis, may represent one such surrogate indicator. METHODS: Mitochondrial function was assessed by respirometry experiment in fibroblasts derived from idiopathic patients (n = 47) in normal conditions and in experimental settings that do not permit glycolysis and therefore force energy production through mitochondrial function. Respiratory parameters and clinical measures were correlated with bivariate analysis. Machine-learning-based classification and regression trees were used to classify patients on the basis of biochemical and clinical measures. The effects of mitochondrial respiration on α-synuclein stress were assessed monitoring the protein phosphorylation in permitting versus restrictive glycolysis conditions. RESULTS: Bioenergetic properties in peripheral fibroblasts correlate with clinical measures in idiopathic patients, and the correlation is stronger with predominantly nondopaminergic signs. Bioenergetic analysis under metabolic stress, in which energy is produced solely by mitochondria, shows that patients' fibroblasts can augment respiration, therefore indicating that mitochondrial defects are reversible. Forcing energy production through mitochondria, however, favors α-synuclein stress in different cellular experimental systems. Machine-learning-based classification identified different groups of patients in which increasing disease severity parallels higher mitochondrial respiration. CONCLUSION: The suppression of mitochondrial activity in PD may be an adaptive strategy to cope with concomitant pathogenic factors. Moreover, mitochondrial measures in fibroblasts are potential peripheral biomarkers to follow disease progression. © 2019 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.

Transcriptomic analysis of FUCA1 knock-down in keratinocytes reveals new insights into the pathogenesis of fucosidosis skin lesions.

Fucosidosis is a rare lysosomal storage disease which has been classified into two subtypes, depending on the severity of clinical signs and symptoms. Fucosidosis patients' skin abnormalities include angiokeratoma corporis diffusum, widespread telangiectasia, thick skin, hyperhidrosis and hypohidrosis, acrocyanosis and distal transverse nail bands. It has been described that >50% of fucosidosis patients have angiokeratoma. At molecular level, fucosidosis is caused by lysosomal alpha-L-fucosidase (FUCA1) gene mutations. Obtaining samples for functional studies has been challenging due to the inherent difficulty in finding affected individuals. The effect of FUCA1 dysfunction on gene expression is unknown. The aim of this study was to analyse, in keratinocytes, the transcriptomic effect of FUCA1 knock-down for a better understanding of skin lesions' pathogenesis affecting fucosidosis patients. FUCA1 knock-down (siRNA) was performed in human HaCaT immortalised keratinocytes. Affymetrix arrays and qPCR were used for analysing gene expression. Bioinformatics was used for functional clustering of modified genes. In total, 387 genes showed differential expression between FUCA1 silenced and non-silenced cells (222 up-regulated and 165 down-regulated). Up-regulated genes belonged to two major groups: keratinocyte differentiation/epidermal development (n = 17) and immune response (n = 61). Several transcription factors were up-regulated in FUCA1-siRNA transfected cells. This effect might partly have been produced by abnormal transcription factor expression, that is FOXN1. We thus propose that fucosidosis-related skin lesions (eg angiokeratoma) and those of other diseases (eg psoriasis) might be caused by dysfunctions in common aetiological overlapping molecular cascades.

Immunohistochemical and molecular profiling of histologically defined apocrine carcinomas of the breast.

Despite the marked improvement in the understanding of molecular mechanisms and classification of apocrine carcinoma, little is known about its specific molecular genetic alterations and potentially targetable biomarkers. In this study, we explored immunohistochemical and molecular genetic characteristics of 37 invasive apocrine carcinomas using immunohistochemistry (IHC), fluorescent in situ hybridization (FISH), multiplex ligation-dependent probe amplification (MLPA), and next-generation sequencing (NGS) assays. IHC revealed frequent E-cadherin expression (89%), moderate (16%) proliferation activity [Ki-67, phosphohistone H3], infrequent (~10%) expression of basal cell markers [CK5/6, CK14, p63, caveolin-1], loss of PTEN (83%), and overexpression of HER2 (32%), EGFR (41%), cyclin D1 (50%), and MUC-1 (88%). MLPA assay revealed gene copy gains of MYC, CCND1, ZNF703, CDH1, and TRAF4 in 50% or greater of the apocrine carcinomas, whereas gene copy losses frequently affected BRCA2 (75%), ADAM9 (54%), and BRCA1 (46%). HER2 gain, detected by MLPA in 38% of the cases, was in excellent concordance with HER2 results obtained by IHC/FISH (κ = 0.915, P < .001). TOP2A gain was observed in one case, while five cases (21%) exhibited TOP2A loss. Unsupervised hierarchical cluster analysis revealed two distinct clusters: HER2-positive and HER2-negative (P = .03 and .04, respectively). NGS assay revealed mutations of the TP53 (2 of 7, 29%), BRAF/KRAS (2 of 7, 29%), and PI3KCA/PTEN genes (7 of 7, 100%). We conclude that morphologically defined apocrine carcinomas exhibit complex molecular genetic alterations that are consistent with the "luminal-complex" phenotype. Some of the identified molecular targets are promising biomarkers; however, functional studies are needed to prove these observations.

El síndrome 22q11.2D S como un subtipo genético de esquizofrenia / 22q11.2 DS Syndrome as a Genetic Subtype of Schizophrenia

Introducción: El síndrome de deleción 22q11.2 (22q11.2 DS) se produce por microdeleciones del brazo largo del cromosoma 22 en la región q11.2. Después del síndrome de Down, es el segundo síndrome genético más común. En pacientes con esquizofrenia, el 22q11.2 DS tiene una prevalencia del 2%, mientras que en personas con esquizofrenia seleccionadas por características físicas específicas, aumenta un 32-53%. Objetivo: Describir las generalidades del 22q11.2 DS, sus características clínicas, los aspectos genético-moleculares y la frecuencia de la microdeleción de 22q11.2 en diferentes poblaciones. Métodos: Se hizo una revisión desde 1967 hasta 2013 en bases de datos de publicaciones científicas, orientada a recopilar artículos sobre el 22q11.2 DS y su relación con la esquizofrenia. Resultados: El 22q11.2 DS es una entidad genética que se asocia a un fenotipo variable relacionado con defectos congénitos en diferentes tejidos y órganos, así como a una alta frecuencia de trastornos psiquiátricos, particularmente la esquizofrenia. Se ha identificado alta prevalencia en grupos de personas con esquizofrenia seleccionadas por características sindrómicas comunes, como dificultades de aprendizaje, rasgos faciales típicos, anomalías palatales y defectos cardiacos congénitos. Las técnicas de FISH, qPCR, MLPA y, recientemente, aCGH y NGS se están usando para diagnosticar esta microdeleción. Conclusiones: En la práctica clínica es importante tener presente que las personas con 22q11.2 DS tienen alto riesgo de sufrir esquizofrenia, ya que la región 22q11.2 alberga genes candidatos relacionados con vulnerabilidad a esquizofrenia. Se considera que la concomitancia de esta enfermedad y 22q11.2 DS representa un subtipo genético de esquizofrenia. y métodos citogenéticos y moleculares para diagnosticar a este grupo de pacientes y optimizar un abordaje multidisciplinario en su seguimiento.

Introduction: The 22q11.2 deletion syndrome (22q11.2 DS) is associated with the microdeletion of this chromosomal region, and represents the second most common genetic syndrome after Down's syndrome. In patients with schizophrenia, 22q11.2 DS has a prevalence of 2%, and in selected groups can be increased to between 32-53%. Objective: To describe the generalities of 22q11.2 DS syndrome as a genetic subtype of schizophrenia, its clinical characteristics, molecular genetic aspects, and frequency in different populations. Methods: A review was performed from 1967 to 2013 in scientific databases, compiling articles about 22q11.2 DS syndrome and its association with schizophrenia. Results: The 22q11.2 DS syndrome has a variable phenotype associated with other genetic syndromes, birth defects in many tissues and organs, and a high rate of psychiatric disorders, particularly schizophrenia. Likewise, it has been identified in clinical populations with schizophrenia selected by the presence of common syndromic characteristics. FISH, qPCR and MLPA techniques, and recently, aCGH and NGS technologies, are being used to diagnose this microdeletion. Conclusions: It is important in clinical practice to remember that people suffering the 22q11.2 DS have a high genetic risk for developing schizophrenia, and it is considered that the simultaneous presence of this disease and 22q11.2 DS represents a genetic subtype of schizophrenia. There are clear phenotypic criteria, molecular and cytogenetic methods to diagnose this group of patients, and to optimize a multidisciplinary approach in their monitoring.

Bioenergetic and proteolytic defects in fibroblasts from patients with sporadic Parkinson's disease.

BACKGROUND: Parkinson's disease (PD) is a complex disease and the current interest and focus of scientific research is both investigating the variety of causes that underlie PD pathogenesis, and identifying reliable biomarkers to diagnose and monitor the progression of pathology. Investigation on pathogenic mechanisms in peripheral cells, such as fibroblasts derived from patients with sporadic PD and age/gender matched controls, might generate deeper understanding of the deficits affecting dopaminergic neurons and, possibly, new tools applicable to clinical practice. METHODS: Primary fibroblast cultures were established from skin biopsies. Increased susceptibility to the PD-related toxin rotenone was determined with apoptosis- and necrosis-specific cell death assays. Protein quality control was evaluated assessing the efficiency of the Ubiquitin Proteasome System (UPS) and protein levels of autophagic markers. Changes in cellular bioenergetics were monitored by measuring oxygen consumption and glycolysis-dependent medium acidification. The oxido-reductive status was determined by detecting mitochondrial superoxide production and oxidation levels in proteins and lipids. RESULTS: PD fibroblasts showed higher vulnerability to necrotic cell death induced by complex I inhibitor rotenone, reduced UPS function and decreased maximal and rotenone-sensitive mitochondrial respiration. No changes in autophagy and redox markers were detected. CONCLUSIONS: Our study shows that increased susceptibility to rotenone and the presence of proteolytic and bioenergetic deficits that typically sustain the neurodegenerative process of PD can be detected in fibroblasts from idiopathic PD patients. Fibroblasts might therefore represent a powerful and minimally invasive tool to investigate PD pathogenic mechanisms, which might translate into considerable advances in clinical management of the disease.

Differences and homologies of chromosomal alterations within and between breast cancer cell lines: a clustering analysis.

BACKGROUND: The MCF7 (ER+/HER2-), T47D (ER+/HER2-), BT474 (ER+/HER2+) and SKBR3 (ER-/HER2+) breast cancer cell lines are widely used in breast cancer research as paradigms of the luminal and HER2 phenotypes. Although they have been subjected to cytogenetic analysis, their chromosomal abnormalities have not been carefully characterized, and their differential cytogenetic profiles have not yet been established. In addition, techniques such as comparative genomic hybridization (CGH), microarray-based CGH and multiplex ligation-dependent probe amplification (MLPA) have described specific regions of gains, losses and amplifications of these cell lines; however, these techniques cannot detect balanced chromosomal rearrangements (e.g., translocations or inversions) or low frequency mosaicism. RESULTS: A range of 19 to 26 metaphases of the MCF7, T47D, BT474 and SKBR3 cell lines was studied using conventional (G-banding) and molecular cytogenetic techniques (multi-color fluorescence in situ hybridization, M-FISH). We detected previously unreported chromosomal changes and determined the content and frequency of chromosomal markers. MCF7 and T47D (ER+/HER2-) cells showed a less complex chromosomal make up, with more numerical than structural alterations, compared to BT474 and SKBR3 (HER2+) cells, which harbored the highest frequency of numerical and structural aberrations. Karyotype heterogeneity and clonality were determined by comparing all metaphases within and between the four cell lines by hierarchical clustering. The latter analysis identified five main clusters. One of these clusters was characterized by numerical chromosomal abnormalities common to all cell lines, and the other four clusters encompassed cell-specific chromosomal abnormalities. T47D and BT474 cells shared the most chromosomal abnormalities, some of which were shared with SKBR3 cells. MCF7 cells showed a chromosomal pattern that was markedly different from those of the other cell lines. CONCLUSIONS: Our study provides a comprehensive and specific characterization of complex chromosomal aberrations of MCF7, T47D, BT474 and SKBR3 cell lines.The chromosomal pattern of ER+/HER2- cells is less complex than that of ER+/HER2+ and ER-/HER2+ cells. These chromosomal abnormalities could influence the biologic and pharmacologic response of cells. Finally, although gene expression profiling and aCGH studies have classified these four cell lines as luminal, our results suggest that they are heterogeneous at the cytogenetic level.

Expression of TRF2 and GAPDH in the aging of the in vitro ovarian surface epithelial cells / Expresión de TRF2 y GAPDH en el envejecimiento de las células del epitelio superficial del ovario in vitro / Expressão de TRF2 e GAPDH no envelhecimento do epitélio superficial do ovário in vitro

GAPDH can bind single-strand telomere DNA both in vitro and in vivo. Thus, it was hypothesised that GAPDH has an important role in protecting the telomeres, role that could be shared with TRF2, a well-known telomeric protein involved in a myriad of functions related to telomere homeostasis. Objective: The aim of this study was to determine if there was a correlation between the expression of these genes in the in vitro ovarian surface epithelium. Materials and methods: The relative expression of each gene was established by qRT-PCR in primary cell cultures of the ovarian surface epithelium from 22 healthy mestizo Colombian donors. Results: The Kendall and Spearman non-parametric tests established a significant correlation between the levels of expression in subsequent passages of the cell line, in an age-independent way. Conclusion: Our findings suggest a synergistic effect between TRF2 and GAPDH that could counter telomere shortening in vitro.

Se ha demostrado que la proteína GAPDH se puede unir al ADN telomérico de cadena sencilla, tanto in vitro como in vivo. Por lo tanto, se ha planteado la hipótesis de que la GAPDH juega un papel importante en la protección de los telómeros, papel que podría ser compartido con la TRF2, proteína que participa en una gran variedad de funciones relacionadas con la homeostasis telomérica. Objetivo: el objetivo de este estudio fue determinar si existe una correlación entre la expresión de ambos genes en el epitelio superficial del ovario in vitro. Materiales y métodos: la expresión relativa de cada gen fue establecida mediante qRT-PCR, en cultivos primarios de células del epitelio superficial del ovario provenientes de un grupo de 22 donantes colombianas mestizas sanas. Resultados: las pruebas no paramétricas de Kendall y Spearman permitieron establecer que existe una correlación significativa entre los niveles de expresión de GAPDH y TRF2 a lo largo de la historia replicativa de los cultivos, en forma independiente de la edad de las donantes. Conclusión: nuestros resultados sugieren un efecto sinérgico entre TRF2 y GAPDH, que podría estar orientado a contrarrestar la reducción de los telómeros in vitro.

Tem se demonstrado que GAPDH pode-se unir ao DNA telomérico de cadeia simples, tanto in vitro quanto in vivo. Portanto, tem se apresentado a hipótese de que GAPDH joga um papel importante na proteção dos telómeros, papel que poderia ser compartilhado com TRF2, proteína que participa em uma grande variedade de funções relacionadas com a homeostase telomérica. Objetivo. O objetivo deste estudo foi determinar se existe uma correlação entre a expressão de ambos os genes no epitélio superficial do ovário in vitro. Materiais e métodos: A expressão relativa de cada gene foi estabelecida mediante qRT-PCR em cultivos primários de células do epitélio superficial do ovário provenientes de um grupo de 22 doadoras colombianas mestiças sanas. Resultados. As provas não paramétricas de Kendall e Spearman permitiram estabelecer que existe uma correlação significativa entre os níveis de expressão de GAPDH e TRF2 ao longe da história replicativa dos cultivos, em forma independente da idade das doadoras. Conclusão. Nossos resultados sugerem um efeito sinérgico entre TRF2 e GAPDH que poderia estar orientado a contra-arrestar a redução dos telómeros in vitro.