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1.
bioRxiv ; 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38746229

RESUMO

Alu elements are non-autonomous Short INterspersed Elements (SINEs) derived from the 7SL RNA gene that are present at over one million copies in human genomic DNA. Alu mobilizes by a mechanism known as retrotransposition, which requires the Long INterspersed Element-1 (LINE-1 or L1) ORF2 -encoded protein (ORF2p). Here, we demonstrate that HeLa strains differ in their capacity to support Alu retrotransposition. Human Alu elements retrotranspose efficiently in HeLa-HA and HeLa-CCL2 ( Alu -permissive) strains, but not in HeLa-JVM or HeLa-H1 ( Alu -nonpermissive) strains. A similar pattern of retrotransposition was observed for other 7SL RNA -derived SINEs and tRNA -derived SINEs. In contrast, mammalian LINE-1s, a zebrafish LINE, a human SINE-VNTR - Alu ( SVA ) element, and an L1 ORF1 -containing messenger RNA can retrotranspose in all four HeLa strains. Using an in vitro reverse transcriptase-based assay, we show that Alu RNAs associate with ORF2p and are converted into cDNAs in both Alu -permissive and Alu -nonpermissive HeLa strains, suggesting that 7SL - and tRNA -derived SINE RNAs use strategies to 'hijack' L1 ORF2p that are distinct from those used by SVA elements and ORF1 -containing mRNAs. These data further suggest ORF2p associates with the Alu RNA poly(A) tract in both Alu -permissive and Alu -nonpermissive HeLa strains, but that Alu retrotransposition is blocked after this critical step in Alu -nonpermissive HeLa strains.

2.
J Neurochem ; 168(2): 69-82, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38178803

RESUMO

N-acetylaspartate (NAA) is an abundant central nervous system amino acid derivative that is tightly coupled to mitochondria and energy metabolism in neurons. A reduced NAA signature is a prominent early pathological biomarker in multiple neurodegenerative diseases and becomes progressively more pronounced as disease advances. Because NAA synthesis requires aspartate drawn directly from mitochondria, we argued that this process is in direct competition with oxidative phosphorylation for substrate and that sustained high levels of NAA synthesis would be incompatible with pathological energy crisis. We show here that over-expression of the rate-limiting NAA synthetic enzyme in the hippocampus of the 5x familial Alzheimer's disease (5xFAD) mouse results in an exaggerated pathological ATP deficit and accelerated cognitive decline. Over-expression of NAA synthase did not increase amyloid burden or result in cell loss but did significantly deplete mitochondrial aspartate and impair the ability of mitochondria to oxidize glutamate for adenosine triphosphate (ATP) synthesis. These results define NAA as a sink for energetic substrate and suggest initial pathological reductions in NAA are part of a response to energetic crisis designed to preserve substrate bioavailability for mitochondrial ATP synthesis.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Camundongos , Animais , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Ácido Aspártico/metabolismo , Trifosfato de Adenosina/metabolismo
3.
iScience ; 26(11): 108143, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37915599

RESUMO

Studies have reported increased intestinal permeability in multiple sclerosis (MS) patients and its mouse model experimental autoimmune encephalomyelitis (EAE). However, the mechanisms driving increased intestinal permeability that in turn exacerbate neuroinflammation during EAE remain unclear. Here we showed that vancomycin preserved the integrity of the intestinal barrier, while also suppressing gut trypsin activity, enhancing the relative abundance of specific Lactobacilli and ameliorating disease during EAE. Furthermore, Lactobacilli enriched in the gut of vancomycin-treated EAE mice at day 3 post immunization negatively correlated with gut trypsin activity and EAE severity. In untreated EAE mice, we observed increased intestinal permeability and increased intestinal protease activated receptor 2 (PAR2) expression at day 3 post immunization. Prior studies have shown that trypsin increases intestinal permeability by activating PAR2. Our results suggest that the interaction between intestinal PAR2 and trypsin may be a key modulator of intestinal permeability and disease severity during EAE.

4.
Eur J Neurol ; 30(10): 3032-3046, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37340928

RESUMO

BACKGROUND: Neuroinflammation in the cerebral cortex of patients who died with liver cirrhosis and neuroinflammation, and neuronal death in the cerebellum of patients who died with steatohepatitis or cirrhosis, were reported. Hippocampal neuroinflammation could contribute to cognitive decline in patients with liver disease, but this has yet to be studied. The study aims were to assess if hippocampus from patients who died with steatohepatitis or cirrhosis showed: (i) glial activation, (ii) altered cytokine content, (iii) immune cell infiltration, (iv) neuronal apoptosis and (v) neuronal loss. METHODS: Post-mortem hippocampus was obtained from 6 controls, 19 patients with steatohepatitis (SH) and 4 patients with liver cirrhosis. SH patients were divided into SH1 (n = 9), SH2 (n = 6) and SH3 (n = 4) groups depending on disease severity. Glial activation, IL-1ß and TNFα content, CD4 lymphocyte and monocyte infiltration, neuronal apoptosis and neuronal loss were analyzed by immunohistochemistry. RESULTS: Patients who died in SH1 showed astrocyte activation, whereas those who died in SH2 also showed microglial activation, CD4 lymphocyte and monocyte infiltration, neuronal apoptosis and neuronal loss. These changes remained in patients in SH3, who also showed increased IL-1ß and TNFα. Patients who died of liver cirrhosis did not show CD4 lymphocyte infiltration, neuronal apoptosis or increase in TNFα, but still showed glial activation, increased IL-1ß and neuronal loss. CONCLUSIONS: Patients with steatohepatitis showed glial activation, immune cell infiltration, apoptosis and neuronal loss. Glial activation and neuronal loss remained in cirrhotic patients. This may explain the irreversibility of some cognitive alterations in hepatic encephalopathy. Cognitive reserve may contribute to different grades of cognitive impairment despite similar neuronal loss.


Assuntos
Fígado Gorduroso , Fator de Necrose Tumoral alfa , Humanos , Doenças Neuroinflamatórias , Cirrose Hepática/complicações , Fígado Gorduroso/patologia , Hipocampo/patologia
5.
Biomedicines ; 10(6)2022 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-35740285

RESUMO

Patients with non-alcoholic fatty liver disease (NAFLD) may show mild cognitive impairment. Neuroinflammation in the hippocampus mediates cognitive impairment in rat models of minimal hepatic encephalopathy (MHE). Treatment with rifaximin reverses cognitive impairment in a large proportion of cirrhotic patients with MHE. However, the underlying mechanisms remain unclear. The aims of this work were to assess if rats with mild liver damage, as a model of NAFLD, show neuroinflammation in the hippocampus and impaired cognitive function, if treatment with rifaximin reverses it, and to study the underlying mechanisms. Mild liver damage was induced with carbon-tetrachloride. Infiltration of immune cells, glial activation, and cytokine expression, as well as glutamate receptors expression in the hippocampus and cognitive function were assessed. We assessed the effects of daily treatment with rifaximin on the alterations showed by these rats. Rats with mild liver damage showed hippocampal neuroinflammation, reduced membrane expression of glutamate N-methyl-D-aspartate (NMDA) receptor subunits, and impaired spatial memory. Increased C-C Motif Chemokine Ligand 2 (CCL2), infiltration of monocytes, microglia activation, and increased tumor necrosis factor α (TNFα) were reversed by rifaximin, that normalized NMDA receptor expression and improved spatial memory. Thus, rifaximin reduces neuroinflammation and improves cognitive function in rats with mild liver damage, being a promising therapy for patients with NAFLD showing mild cognitive impairment.

6.
Front Pediatr ; 9: 788997, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34956989

RESUMO

Background: Delirium, bed immobilization, and heavy sedation are among the major contributors of pediatric post-intensive care syndrome. Recently, the Society of Critical Care Medicine has proposed the implementation of daily interventions to minimize the incidence of these morbidities and optimize children functional outcomes and quality of life. Unfortunately, these interventions require important clinical and economical efforts which prevent their use in many pediatric intensive care units (PICU). Aim: First, to evaluate the feasibility and safety of a PICU bundle implementation prioritizing delirium screening and treatment, early mobilization (<72 h from PICU admission) and benzodiazepine-limited sedation in a human resource-limited PICU. Second, to evaluate the incidence of delirium and describe the early mobilization practices and sedative drugs used during the pre- and post-implementation periods. Third, to describe the barriers and adverse events encountered during early mobilization. Methods: This observational study was structured in a pre- (15th November 2019-30th June 2020) and post-implementation period (1st July 2020-31st December 2020). All patients admitted in PICU for more than 72 h during the pre and post-implementation period were included in the study. Patients were excluded if early mobilization was contraindicated. During the pre-implementation period, a rehabilitation program including delirium screening and treatment, early mobilization and benzodiazepine-sparing sedation guidelines was developed and all PICU staff trained. During the post-implementation period, delirium screening with the Connell Assessment of Pediatric Delirium scale was implemented at bedside. Early mobilization was performed using a structured tiered protocol and a new sedation protocol, limiting the use of benzodiazepine, was adopted. Results: Two hundred and twenty-five children were enrolled in the study, 137 in the pre-implementation period and 88 in the post-implementation period. Adherence to delirium screening, benzodiazepine-limited sedation and early mobilization was 90.9, 81.1, and 70.4%, respectively. Incidence of delirium was 23% in the post-implementation period. The median cumulative dose of benzodiazepines corrected for the total number of sedation days (mg/kg/sedation days) was significantly lower in the post-implementation period compared with the pre-implementation period: [0.83 (IQR: 0.53-1.31) vs. 0.74 (IQR: 0.55-1.16), p = 0.0001]. The median cumulative doses of fentanyl, remifentanil, and morphine corrected for the total number of sedation days were lower in the post-implementation period, but these differences were not significant. The median number of mobilizations per patient and the duration of each mobilization significantly increased in the post-implementation period [3.00 (IQR: 2.0-4.0) vs. 7.00 (IQR: 3.0-12.0); p = 0.004 and 4 min (IQR: 3.50-4.50) vs. 5.50 min (IQR: 5.25-6.5); p < 0.0001, respectively]. Barriers to early mobilization were: disease severity and bed rest orders (55%), lack of physicians' order (20%), lack of human resources (20%), and lack of adequate devices for patient mobilization (5%). No adverse events related to early mobilization were reported in both periods. Duration of mechanical ventilation and PICU length of stay was significantly lower in the post-implementation period as well as the occurrence of iatrogenic withdrawal syndrome. Conclusion: This study showed that the implementation of a PICU liberation bundle prioritizing delirium screening and treatment, benzodiazepine-limited sedation and early mobilization was feasible and safe even in a human resource-limited PICU. Further pediatric studies are needed to evaluate the clinical impact of delirium, benzodiazepine-limited sedation and early mobilization protocols on patients' long-term functional outcomes and on hospital finances.

7.
Monaldi Arch Chest Dis ; 92(3)2021 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-34964575

RESUMO

Six minute walk test (6MWT) is a field exercise test widely used in clinical practice, both in adults and in pediatric patients. The primary aim of the study is to evaluate the physical performance of the subjects and compare them with the predicted Italian values. The secondary aim is to verify the possible relationship between the 6MWT distance (6MWD) and the clinical variables of the sample. Italian children between 6-11 years affected by CF were recruited from 9 regional centers for CF. Short questionnaire assessments about their health state and physical activity routine was administered. Anthropometric characteristics were measured before the test and, peripheral oxygen saturation (SpO2), heart and respiratory rate were measured before and after a 6-minute walk test. The tests were performed according to the American Thoracic Society (ATS) guidelines. 6MWD was compared with the predicted distance calculated by the reference equation for healthy subjects of the same age. A total of 132 children were recruited (70 male) and completed the assessment. The mean (±SD) for 6MWD was 557.4 (±69.9), male = 551.4 (±80.0), female = 560.4 (±63.3), however the predicted distance mean was 605 m. A total of 101(76.5%) subjects practice regular physical activity. A total of 31 (23%) had a FEV1 lower than their lower limits of normal (LLN). Functional performance on the 6MWT was poorer among the CF patients than among the predicted distance estimated with Italian values. The correlation with the amount of physical activity and 6MWD has been verified.


Assuntos
Fibrose Cística , Adulto , Criança , Fibrose Cística/diagnóstico , Fibrose Cística/epidemiologia , Exercício Físico , Teste de Esforço , Feminino , Humanos , Masculino , Teste de Caminhada , Caminhada
8.
Biomedicines ; 9(8)2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34440206

RESUMO

In patients with liver cirrhosis, minimal hepatic encephalopathy (MHE) is triggered by a shift in peripheral inflammation, promoting lymphocyte infiltration into the brain. Rifaximin improves neurological function in MHE by normalizing peripheral inflammation. Patients who died with steatohepatitis showed T-lymphocyte infiltration and neuroinflammation in the cerebellum, suggesting that MHE may already occur in these patients. The aims of this work were to assess, in a rat model of mild liver damage similar to steatohepatitis, whether: (1) the rats show impaired motor coordination in the early phases of liver damage; (2) this is associated with changes in the immune system and infiltration of immune cells into the brain; and (3) rifaximin improves motor incoordination, associated with improved peripheral inflammation, reduced infiltration of immune cells and neuroinflammation in the cerebellum, and restoration of the alterations in neurotransmission. Liver damage was induced by carbon tetrachloride (CCl4) injection over four weeks. Peripheral inflammation, immune cell infiltration, neuroinflammation, and neurotransmission in the cerebellum and motor coordination were assessed. Mild liver damage induces neuroinflammation and altered neurotransmission in the cerebellum and motor incoordination. These alterations are associated with increased TNFa, CCL20, and CX3CL1 in plasma and cerebellum, IL-17 and IL-15 in plasma, and CCL2 in cerebellum. This promotes T-lymphocyte and macrophage infiltration in the cerebellum. Early treatment with rifaximin prevents the shift in peripheral inflammation, immune cell infiltration, neuroinflammation, and motor incoordination. This report provides new clues regarding the mechanisms of the beneficial effects of rifaximin, suggesting that early rifaximin treatment could prevent neurological impairment in patients with steatohepatitis.

9.
J Evol Biol ; 34(10): 1624-1636, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34378263

RESUMO

Understanding how species can thrive in a range of environments is a central challenge for evolutionary ecology. There is strong evidence for local adaptation along large-scale ecological clines in insects. However, potential adaptation among neighbouring populations differing in their environment has been studied much less. We used RAD sequencing to quantify genetic divergence and clustering of ten populations of the field cricket Gryllus campestris in the Cantabrian Mountains of northern Spain, and an outgroup on the inland plain. Our populations were chosen to represent replicate high and low altitude habitats. We identified genetic clusters that include both high and low altitude populations indicating that the two habitat types do not hold ancestrally distinct lineages. Using common-garden rearing experiments to remove environmental effects, we found evidence for differences between high and low altitude populations in physiological and life-history traits. As predicted by the local adaptation hypothesis, crickets with parents from cooler (high altitude) populations recovered from periods of extreme cooling more rapidly than those with parents from warmer (low altitude) populations. Growth rates also differed between offspring from high and low altitude populations. However, contrary to our prediction that crickets from high altitudes would grow faster, the most striking difference was that at high temperatures, growth was fastest in individuals from low altitudes. Our findings reveal that populations a few tens of kilometres apart have independently evolved adaptations to their environment. This suggests that local adaptation in a range of traits may be commonplace even in mobile invertebrates at scales of a small fraction of species' distributions.


Assuntos
Gryllidae , Aclimatação , Adaptação Fisiológica/genética , Altitude , Animais , Evolução Biológica , Gryllidae/genética , Humanos
10.
Exp Cell Res ; 403(1): 112594, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-33823179

RESUMO

COVID-19 was declared an international public health emergency in January, and a pandemic in March of 2020. There are over 125 million confirmed COVID-19 cases that have caused over 2.7 million deaths worldwide as of March 2021. COVID-19 is caused by the SARS-CoV-2 virus. SARS-CoV-2 presents a surface "spike" protein that binds to the ACE2 receptor to infect host cells. In addition to the respiratory tract, SARS-Cov-2 can also infect cells of the oral mucosa, which also express the ACE2 receptor. The spike and ACE2 proteins are highly glycosylated with sialic acid modifications that direct viral-host interactions and infection. Maackia amurensis seed lectin (MASL) has a strong affinity for sialic acid modified proteins and can be used as an antiviral agent. Here, we report that MASL targets the ACE2 receptor, decreases ACE2 expression and glycosylation, suppresses binding of the SARS-CoV-2 spike protein, and decreases expression of inflammatory mediators by oral epithelial cells that cause ARDS in COVID-19 patients. In addition, we report that MASL also inhibits SARS-CoV-2 infection of kidney epithelial cells in culture. This work identifies MASL as an agent with potential to inhibit SARS-CoV-2 infection and COVID-19 related inflammatory syndromes.


Assuntos
Antivirais/farmacologia , Tratamento Farmacológico da COVID-19 , Lectinas/farmacologia , Boca/efeitos dos fármacos , SARS-CoV-2/efeitos dos fármacos , Glicoproteína da Espícula de Coronavírus/efeitos dos fármacos , Progressão da Doença , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Interações entre Hospedeiro e Microrganismos/efeitos dos fármacos , Humanos , Maackia/metabolismo , SARS-CoV-2/patogenicidade , Glicoproteína da Espícula de Coronavírus/metabolismo
11.
Mol Ther Methods Clin Dev ; 20: 520-534, 2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33614826

RESUMO

Recent advances in adeno-associated viral (AAV) capsid variants with novel oligotropism require validation in models of disease in order to be viable candidates for white matter disease gene therapy. We present here an assessment of the biodistribution, tropism, and efficacy of a novel AAV capsid variant (AAV/ Olig001) in a model of Canavan disease. We first define a combination of dose and route of administration of an AAV/Olig001-GFP reporter conducive to widespread CNS oligodendrocyte transduction in acutely symptomatic animals that model the Canavan brain at time of diagnosis. Administration of AAV/Olig001-GFP resulted in >70% oligotropism in all regions of interest except the cerebellum without the need for lineage-specific expression elements. Intracerebroventricular infusion into the cerebrospinal fluid (CSF) was identified as the most appropriate route of administration and employed for delivery of an AAV/Olig001 vector to reconstitute oligodendroglial aspartoacylase (ASPA) in adult Canavan mice, which resulted in a dose-dependent rescue of ASPA activity, motor function, and a near-total reduction in vacuolation. A head-to-head efficacy comparison with astrogliotropic AAV9 highlighted a significant advantage conferred by oligotropic AAV/Olig001 that was independent of overall transduction efficiency. These results support the continued development of AAV/Olig001 for advancement to clinical application to white matter disease.

12.
Front Endocrinol (Lausanne) ; 11: 585130, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33329391

RESUMO

Polycystic ovary syndrome (PCOS) is a heterogeneous endocrine disorder characterized by hyperandrogenism, ovulatory dysfunction, and polycystic ovaries. Epidemiological findings revealed that women with PCOS are prone to develop certain cancer types due to their shared metabolic and endocrine abnormalities. However, the mechanism that relates PCOS and oncogenesis has not been addressed. Herein, in this review article the genomic status, transcriptional and protein profiles of 264 strongly PCOS related genes (PRG) were evaluated in endometrial cancer (EC), ovarian cancer (OV) and breast cancer (BC) exploring oncogenic databases. The genomic alterations of PRG were significantly higher when compared with a set of non-diseases genes in all cancer types. PTEN had the highest number of mutations in EC, TP53, in OC, and FSHR, in BC. Based on clinical data, women older than 50 years and Black or African American females carried the highest ratio of genomic alterations among all cancer types. The most altered signaling pathways were p53 in EC and OC, while Fc epsilon RI in BC. After evaluating PRG in normal and cancer tissue, downregulation of the differentially expressed genes was a common feature. Less than 30 proteins were up and downregulated in all cancer contexts. We identified 36 highly altered genes, among them 10 were shared between the three cancer types analyzed, which are involved in the cell proliferation regulation, response to hormone and to endogenous stimulus. Despite limited PCOS pharmacogenomics studies, 10 SNPs are reported to be associated with drug response. All were missense mutations, except for rs8111699, an intronic variant characterized as a regulatory element and presumably binding site for transcription factors. In conclusion, in silico analysis revealed key genes that might participate in PCOS and oncogenesis, which could aid in early cancer diagnosis. Pharmacogenomics efforts have implicated SNPs in drug response, yet still remain to be found.


Assuntos
Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/genética , Mutação , Neoplasias/tratamento farmacológico , Neoplasias/genética , Farmacogenética , Síndrome do Ovário Policístico/fisiopatologia , Feminino , Humanos , Neoplasias/patologia
13.
Mol Cytogenet ; 13(1): 46, 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33292387

RESUMO

BACKGROUND: Turner syndrome is a genetic disorder that affects women. It is caused by an absent or incomplete X chromosome, which can be presented in mosaicism or not. There are 12 cases of Turner syndrome patients who present structural alterations in autosomal chromosomes. CASE PRESENTATION: The present case report describes a patient with a reciprocal, maternally inherited translocation between chromosomes 2 and 12 with a mosaicism of X monosomy 45,X,t(2;12)(p13;q24)[95]/46,XX,t(2;12)(p13;q24)[5]. Through genetic mapping arrays, altered genes in the patient were determined within the 23 chromosome pairs. These genes were associated with the patient's clinical features using a bioinformatics tool. CONCLUSION: To our knowledge, this is the first case in which a translocation (2;12) is reported in a patient with Turner syndrome and confirmed by conventional cytogenetics, FISH and molecular genetics. Clinical features of our patient are closely related with the loss of one X chromosome, however mild intellectual disability can be likely explained by autosomal genes. The presence of familial translocations was a common finding, thus emphasizing the need for familiar testing for further genetic counselling.

14.
Res Sq ; 2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33106801

RESUMO

COVID-19 was declared an international public health emergency in January, and a pandemic in March of 2020. There are over 23 million confirmed COVID-19 cases that have cause over 800 thousand deaths worldwide as of August 19th, 2020. COVID-19 is caused by the SARS-CoV-2 virus. SARS-CoV-2 presents a surface "spike" protein that binds to the ACE2 receptor to infect host cells. In addition to the respiratory tract, SARS-Cov-2 can also infect cells of the oral mucosa, which also express the ACE2 receptor. The spike and ACE2 proteins are highly glycosylated with sialic acid modifications that direct viral-host interactions and infection. Maackia amurensis seed lectin (MASL) has a strong affinity for sialic acid modified proteins and can be used as an antiviral agent. Here, we report that MASL targets the ACE2 receptor, decreases ACE2 expression and glycosylation, suppresses binding of the SARS-CoV-2 spike protein, and decreases expression of inflammatory mediators by oral epithelial cells that cause ARDS in COVID-19 patients. This work identifies MASL as an agent with potential to inhibit SARS-CoV-2 infection and COVID-19 related inflammatory syndromes.

15.
J Med Case Rep ; 14(1): 136, 2020 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-32867815

RESUMO

BACKGROUND: Anaplastic astrocytoma is a rare disorder in children from 10 to 14 years of age, with an estimated 0.38 new cases per 100,000 people per year worldwide. Panel-based next-generation sequencing opens new possibilities for diagnosis and therapy of rare diseases such as this one. Because it has never been genetically studied in the Ecuadorian population, we chose to genetically characterize an Ecuadorian pediatric patient with anaplastic astrocytoma for the first time. Doing so allows us to provide new insights into anaplastic astrocytoma diagnosis and treatment. CASE PRESENTATION: Our patient was a 13-year-old Mestizo girl with an extensive family history of cancer who was diagnosed with anaplastic astrocytoma. According to ClinVar, SIFT, and PolyPhen, the patient harbored 354 genomic alterations in 100 genes. These variants were mostly implicated in deoxyribonucleic acid (DNA) repair. The top five most altered genes were FANCD2, NF1, FANCA, FANCI, and WRN. Even though TP53 presented only five mutations, the rs11540652 single-nucleotide polymorphism classified as pathogenic was found in the patient and her relatives; interestingly, several reports have related it to Li-Fraumeni syndrome. Furthermore, in silico analysis using the Open Targets Platform revealed two clinical trials for pediatric anaplastic astrocytoma (studying cabozantinib, ribociclib, and everolimus) and 118 drugs that target the patient's variants, but the studies were not designed specifically to treat pediatric anaplastic astrocytoma. CONCLUSIONS: Next-generation sequencing allows genomic characterization of rare diseases; for instance, this study unraveled a pathogenic single-nucleotide polymorphism related to Li-Fraumeni syndrome and identified possible new drugs that specifically target the patient's variants. Molecular tools should be implemented in routine clinical practice for early detection and effective preemptive intervention delivery and treatment.


Assuntos
Astrocitoma , Glioblastoma , Síndrome de Li-Fraumeni , Adolescente , Astrocitoma/genética , Criança , Equador , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos
16.
BMC Med Genomics ; 13(1): 113, 2020 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-32807182

RESUMO

BACKGROUND: Congenital insensitivity to pain with anhidrosis (CIPA) is an extremely rare autosomal recessive disorder characterized by insensitivity to pain, inability to sweat and intellectual disability. CIPA is caused by mutations in the neurotrophic tyrosine kinase receptor type 1 gene (NTRK1) that encodes the high-affinity receptor of nerve growth factor (NGF). CASE PRESENTATION: Here, we present clinical and molecular findings in a 9-year-old girl with CIPA. The high-altitude indigenous Ecuadorian patient presented several health problems such as anhidrosis, bone fractures, self-mutilation, osteochondroma, intellectual disability and Riga-Fede disease. After the mutational analysis of NTRK1, the patient showed a clearly autosomal recessive inheritance pattern with the pathogenic mutation rs763758904 (Arg602*) and the second missense mutation rs80356677 (Asp674Tyr). Additionally, the genomic analysis showed 69 pathogenic and/or likely pathogenic variants in 46 genes possibly related to phenotypic heterogeneity, including the rs324420 variant in the FAAH gene. The gene ontology enrichment analysis showed 28 mutated genes involved in several biological processes. As a novel contribution, the protein-protein interaction network analysis showed that NTRK1, SPTBN2 and GRM6 interact with several proteins of the pain matrix involved in the response to stimulus and nervous system development. CONCLUSIONS: This is the first study that associates clinical, genomics and networking analyses in a Native American patient with consanguinity background in order to better understand CIPA pathogenesis.


Assuntos
Altitude , Marcadores Genéticos , Hipo-Hidrose/patologia , Mutação , Insensibilidade Congênita à Dor/patologia , Dor/patologia , Criança , Análise Mutacional de DNA , Feminino , Genômica , Humanos , Hipo-Hidrose/genética , Hipo-Hidrose/metabolismo , Dor/genética , Dor/metabolismo , Insensibilidade Congênita à Dor/genética , Insensibilidade Congênita à Dor/metabolismo , Mapas de Interação de Proteínas
17.
Genes (Basel) ; 11(7)2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32708340

RESUMO

Telomere maintenance mechanisms (TMM) are used by cancer cells to avoid apoptosis, 85-90% reactivate telomerase, while 10-15% use the alternative lengthening of telomeres (ALT). Due to anti-telomerase-based treatments, some tumors switch from a telomerase-dependent mechanism to ALT; in fact, the co-existence between both mechanisms has been observed in some cancers. Although different elements in the ALT pathway are uncovered, some molecular mechanisms are still poorly understood. Therefore, with the aim to identify potential molecular markers for the study of ALT, we combined in silico approaches in a 411 telomere maintenance gene set. As a consequence, we conducted a genomic analysis of these genes in 31 Pan-Cancer Atlas studies from The Cancer Genome Atlas and found 325,936 genomic alterations; from which, we identified 20 genes highly mutated in the cancer studies. Finally, we made a protein-protein interaction network and enrichment analysis to observe the main pathways of these genes and discuss their role in ALT-related processes, like homologous recombination and homology directed repair. Overall, due to the lack of understanding of the molecular mechanisms of ALT cancers, we proposed a group of genes, which after ex vivo validations, could represent new potential therapeutic markers in the study of ALT.


Assuntos
Neoplasias/genética , Homeostase do Telômero , Predisposição Genética para Doença , Humanos , Neoplasias/metabolismo , Mapas de Interação de Proteínas , Proteínas de Ligação a Telômeros/genética , Proteínas de Ligação a Telômeros/metabolismo
18.
Biomed Res Int ; 2020: 9074760, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32596391

RESUMO

The incidence of cystic fibrosis (CF) and the frequency of the variants reported for CFTR depend on the population; furthermore, CF symptomatology is characterized by obstructive lung disease and pancreatic insufficiency among other symptoms, which are reliant on the individual's genotype. The Ecuadorian population is a mixture of Native Americans, Europeans, and Africans. That population admixture could be the reason for the new mutations reported in a previous study by Ruiz et al. (2019). A panel of 46 Ancestry Informative Markers was used to estimate the ancestral proportions of each available sample (12 samples in total). As a result, the Native American ancestry proportion was the most prevalent in almost all individuals, except for three patients from Guayaquil with the mutation [c.757G>A:p.Gly253Arg; c.1352G>T:p.Gly451Val] who had the highest European composition.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Fibrose Cística/genética , Mutação/genética , Equador , Genótipo , Humanos , Análise de Componente Principal , Grupos Raciais/genética
20.
J Pediatr Genet ; 9(1): 69-75, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31976149

RESUMO

Trisomy 9p syndrome is the fourth most frequent chromosome aberration seen in infants. Duplication of the critical region 9p22p24 leads to mental retardation, psychomotor delay, and craniofacial and digital anomalies. We report a 2-year-old Ecuadorian girl with Trisomy 9p syndrome. Although her phenotype shares characteristics of Noonan syndrome, Giemsa trypsin banding technique shows there is an extra chromosomal segment on chromosome 14, and array analysis shows that it belongs to a duplication of 38 Mb of 9p13.1p24.3. Fluorescence in situ hybridization analysis detected three signals from 9p chromosome. The duplication is de novo, being another unique case of the few reported in the literature.

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