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1.
EMBO Rep ; 25(7): 2974-3007, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38816514

RESUMO

ATP2B1 is a known regulator of calcium (Ca2+) cellular export and homeostasis. Diminished levels of intracellular Ca2+ content have been suggested to impair SARS-CoV-2 replication. Here, we demonstrate that a nontoxic caloxin-derivative compound (PI-7) reduces intracellular Ca2+ levels and impairs SARS-CoV-2 infection. Furthermore, a rare homozygous intronic variant of ATP2B1 is shown to be associated with the severity of COVID-19. The mechanism of action during SARS-CoV-2 infection involves the PI3K/Akt signaling pathway activation, inactivation of FOXO3 transcription factor function, and subsequent transcriptional inhibition of the membrane and reticulum Ca2+ pumps ATP2B1 and ATP2A1, respectively. The pharmacological action of compound PI-7 on sustaining both ATP2B1 and ATP2A1 expression reduces the intracellular cytoplasmic Ca2+ pool and thus negatively influences SARS-CoV-2 replication and propagation. As compound PI-7 lacks toxicity in vitro, its prophylactic use as a therapeutic agent against COVID-19 is envisioned here.


Assuntos
COVID-19 , Cálcio , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , SARS-CoV-2 , Transdução de Sinais , Replicação Viral , Humanos , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/fisiologia , Replicação Viral/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , COVID-19/virologia , COVID-19/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Cálcio/metabolismo , Animais , Proteína Forkhead Box O3/metabolismo , Proteína Forkhead Box O3/genética , Chlorocebus aethiops , Tratamento Farmacológico da COVID-19 , Células Vero , Feminino , ATPases Transportadoras de Cálcio/metabolismo , ATPases Transportadoras de Cálcio/genética , Masculino
2.
Hum Mol Genet ; 31(6): 863-874, 2022 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-34605909

RESUMO

The 10q24.33 locus is known to be associated with susceptibility to cutaneous malignant melanoma (CMM), but the mechanisms underlying this association have been not extensively investigated. We carried out an integrative genomic analysis of 10q24.33 using epigenomic annotations and in vitro reporter gene assays to identify regulatory variants. We found two putative functional single nucleotide polymorphisms (SNPs) in an enhancer and in the promoter of OBFC1, respectively, in neural crest and CMM cells, one, rs2995264, altering enhancer activity. The minor allele G of rs2995264 correlated with lower OBFC1 expression in 470 CMM tumors and was confirmed to increase the CMM risk in a cohort of 484 CMM cases and 1801 controls of Italian origin. Hi-C and chromosome conformation capture (3C) experiments showed the interaction between the enhancer-SNP region and the promoter of OBFC1 and an isogenic model characterized by CRISPR-Cas9 deletion of the enhancer-SNP region confirmed the potential regulatory effect of rs2995264 on OBFC1 transcription. Moreover, the presence of G-rs2995264 risk allele reduced the binding affinity of the transcription factor MEOX2. Biologic investigations showed significant cell viability upon depletion of OBFC1, specifically in CMM cells that were homozygous for the protective allele. Clinically, high levels of OBFC1 expression associated with histologically favorable CMM tumors. Finally, preliminary results suggested the potential effect of decreased OBFC1 expression on telomerase activity in tumorigenic conditions. Our results support the hypothesis that reduced expression of OBFC1 gene through functional heritable DNA variation can contribute to malignant transformation of normal melanocytes.


Assuntos
Melanoma , Neoplasias Cutâneas , Predisposição Genética para Doença , Humanos , Melanoma/patologia , Polimorfismo de Nucleotídeo Único/genética , Neoplasias Cutâneas/patologia , Melanoma Maligno Cutâneo
3.
J Transl Med ; 22(1): 151, 2024 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-38351008

RESUMO

BACKGROUND: Neuroblastoma (NB) represents the most frequent and aggressive form of extracranial solid tumor of infants. Although the overall survival of patients with NB has improved in the last years, more than 50% of high-risk patients still undergo a relapse. Thus, in the era of precision/personalized medicine, the need for high-risk NB patient-specific therapies is urgent. METHODS: Within the PeRsonalizEd Medicine (PREME) program, patient-derived NB tumors and bone marrow (BM)-infiltrating NB cells, derived from either iliac crests or tumor bone lesions, underwent to histological and to flow cytometry immunophenotyping, respectively. BM samples containing a NB cells infiltration from 1 to 50 percent, underwent to a subsequent NB cells enrichment using immune-magnetic manipulation. Then, NB samples were used for the identification of actionable targets and for the generation of 3D/tumor-spheres and Patient-Derived Xenografts (PDX) and Cell PDX (CPDX) preclinical models. RESULTS: Eighty-four percent of NB-patients showed potentially therapeutically targetable somatic alterations (including point mutations, copy number variations and mRNA over-expression). Sixty-six percent of samples showed alterations, graded as "very high priority", that are validated to be directly targetable by an approved drug or an investigational agent. A molecular targeted therapy was applied for four patients, while a genetic counseling was suggested to two patients having one pathogenic germline variant in known cancer predisposition genes. Out of eleven samples implanted in mice, five gave rise to (C)PDX, all preserved in a local PDX Bio-bank. Interestingly, comparing all molecular alterations and histological and immunophenotypic features among the original patient's tumors and PDX/CPDX up to second generation, a high grade of similarity was observed. Notably, also 3D models conserved immunophenotypic features and molecular alterations of the original tumors. CONCLUSIONS: PREME confirms the possibility of identifying targetable genomic alterations in NB, indeed, a molecular targeted therapy was applied to four NB patients. PREME paves the way to the creation of clinically relevant repositories of faithful patient-derived (C)PDX and 3D models, on which testing precision, NB standard-of-care and experimental medicines.


Assuntos
Variações do Número de Cópias de DNA , Neuroblastoma , Lactente , Humanos , Animais , Camundongos , Recidiva Local de Neoplasia , Neuroblastoma/genética , Neuroblastoma/tratamento farmacológico , Neuroblastoma/patologia , Modelos Animais de Doenças , Citometria de Fluxo
4.
Am J Hematol ; 99(8): 1511-1522, 2024 08.
Artigo em Inglês | MEDLINE | ID: mdl-38666530

RESUMO

Congenital Dyserythropoietic Anemia type I (CDA I) is a rare hereditary condition characterized by macrocytic/normocytic anemia, splenomegaly, iron overload, and distinct abnormalities during late erythropoiesis, particularly internuclear bridges between erythroblasts. Diagnosis of CDA I remains challenging due to its rarity, clinical heterogeneity, and overlapping phenotype with other rare hereditary anemias. In this case series, we present 36 patients with suspected CDA I. A molecular diagnosis was successfully established in 89% of cases, identifying 16 patients with CDA I through the presence of 18 causative variants in the CDAN1 or CDIN1 genes. Transcriptomic analysis of CDIN1 variants revealed impaired erythroid differentiation and disruptions in transcription, cell proliferation, and histone regulation. Conversely, 16 individuals received a different diagnosis, primarily pyruvate kinase deficiency. Comparisons between CDA I and non-CDA I patients revealed no significant differences in erythroblast morphological features. However, hemoglobin levels and red blood cell count differed between the two groups, with non-CDA I subjects being more severely affected. Notably, most patients with severe anemia belonged to the non-CDA I group (82% non-CDA I vs. 18% CDA I), with a subsequent absolute prevalence of transfusion dependency among non-CDA I patients (100% vs. 41.7%). All patients exhibited reduced bone marrow responsiveness to anemia, with a more pronounced effect observed in non-CDA I patients. Erythropoietin levels were significantly higher in non-CDA I patients compared to CDA I patients. However, evaluations of erythroferrone, soluble transferrin receptor, and hepcidin revealed no significant differences in plasma concentration between the two groups.


Assuntos
Anemia Diseritropoética Congênita , Humanos , Anemia Diseritropoética Congênita/genética , Anemia Diseritropoética Congênita/diagnóstico , Anemia Diseritropoética Congênita/sangue , Masculino , Feminino , Estudos Retrospectivos , Adulto , Adolescente , Criança , Pré-Escolar , Eritroblastos/patologia , Eritroblastos/metabolismo , Eritropoese/genética , Lactente , Adulto Jovem , Glicoproteínas , Proteínas Nucleares
5.
Hum Genet ; 142(6): 785-808, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37079061

RESUMO

Deleterious variants in collagen genes are the most common cause of hereditary connective tissue disorders (HCTD). Adaptations of the American College of Medical Genetics and Genomics/Association for Molecular Pathology (ACMG/AMP) criteria are still lacking. A multidisciplinary team was set up for developing specifications of the ACMG/AMP criteria for COL1A1, COL1A2, COL2A1, COL3A1, COL5A1, COL5A2, COL11A1, COL11A2 and COL12A1, associated with various forms of HCTD featuring joint hypermobility, which is becoming one of the most common reasons of referral for molecular testing in this field. Such specifications were validated against 209 variants, and resulted effective for classifying as pathogenic and likely pathogenic null alleles without downgrading of the PVS1 level of strength and recurrent Glycine substitutions. Adaptations of selected criteria reduced uncertainties on private Glycine substitutions, intronic variants predicted to affect the splicing, and null alleles with a downgraded PVS1 level of strength. Segregation and multigene panel sequencing data mitigated uncertainties on non-Glycine substitutions by the attribution of one or more benignity criteria. These specifications may improve the clinical utility of molecular testing in HCTD by reducing the number of variants with neutral/conflicting interpretations. Close interactions between laboratory and clinicians are crucial to estimate the a priori utility of molecular test and to improve medical reports.


Assuntos
Variação Genética , Instabilidade Articular , Humanos , Estados Unidos , Testes Genéticos/métodos , Instabilidade Articular/diagnóstico , Instabilidade Articular/genética , Análise de Sequência de DNA/métodos
6.
Blood Cells Mol Dis ; 103: 102779, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37558589

RESUMO

BACKGROUND: Reaching a precise diagnosis in rare inherited anemia is extremely difficult and challenging, especially in areas with limited use of genetic studies, which makes undiagnosed anemia a unique clinical entity in tertiary hematology centers. In this study, we aim at plotting a stepwise diagnostic approach in children with undiagnosed anemia while identifying indications for genetic testing. PATIENTS AND METHODS: A one-year cross-sectional study involved 44 children and adolescents with undiagnosed anemia after undergoing an initial routine panel of investigations. They were classified based on mean corpuscular volume (MCV) into 3 groups: microcytic (n = 19), normocytic (n = 14) and macrocytic (n = 11). An algorithm that included four levels of investigations was devised for each category. RESULTS: After applying a systematic diagnostic approach, 33 patients (75 %) were diagnosed of whom 7 (15 %) had combined diagnoses, while 11 (25 %) patients remained undiagnosed. Based on the first, second, third and fourth levels of investigations, patients were diagnosed, respectively, as follows: of the 11 patients, 7 were microcytic, 3 normocytic and 1 macrocytic; of the 7 patients, 2 were microcytic, 2 normocytic, and 3 macrocytic; of 10 patients, 5 were microcytic, 4 normocytic and 1 macrocytic; finally, of the 16 patients, 8 were microcytic, 6 normocytic and 2 macrocytic. Numbers recorded appear higher than the actual number of the patients because some of them were diagnosed by more than one level of investigation. The diagnoses obtained in the microcytic group showed hemoglobinopathies, iron refractory iron deficiency anemia (IRIDA), membrane defects, sideroblastic anemia, hypo-transferrinemia, a combined diagnosis of sickle cell trait and pyropoikilocytosis. The diagnoses also showed a combined diagnosis of hereditary spherocytosis (HS) and alpha thalassemia minor, and a combined diagnosis of iron deficiency anemia and beta thalassemia minor, while 15 % remained undiagnosed. In the normocytic group, the diagnosis revealed autosomal recessive (AR) HS, vitamin B12 deficiency, pyruvate kinase deficiency (PKD), congenital dyserythropoietic anemia (CDA) type I, Diamond Blackfan anemia and beta thalassemia major. In addition, it showed a combined diagnosis of AR HS and CDA type II, a combined diagnosis of AR HS and PKD, and a combined diagnosis of dehydrated stomatocytosis (DHS) and G6PD carrier, meanwhile 20 % remained undiagnosed. Finally, the macrocytic group was diagnosed by vitamin B12 deficiency, sideroblastic anemia, PKD, a combined diagnosis of PKD and G6PD deficiency carrier, while 45 % remained undiagnosed. CONCLUSION: Conducting a stepwise approach with different levels of investigations may help reach the diagnosis of difficult anemia without having to resort to unnecessary investigations. Combined diagnosis is an important cause of undiagnosed anemia, especially in countries with high frequency of consanguinity. The remaining 25 % of the patients continued to be undiagnosed, requiring more sophisticated investigations.


Assuntos
Anemia Ferropriva , Anemia Sideroblástica , Deficiência de Vitamina B 12 , Talassemia beta , Adolescente , Humanos , Criança , Anemia Ferropriva/diagnóstico , Estudos Transversais , Países em Desenvolvimento
7.
Haematologica ; 108(5): 1335-1348, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36700398

RESUMO

Cardiomyopathy deeply affects quality of life and mortality of patients with b-thalassemia or with transfusion-dependent myelodysplastic syndromes. Recently, a link between Nrf2 activity and iron metabolism has been reported in liver ironoverload murine models. Here, we studied C57B6 mice as healthy control and nuclear erythroid factor-2 knockout (Nrf2-/-) male mice aged 4 and 12 months. Eleven-month-old wild-type and Nrf2-/- mice were fed with either standard diet or a diet containing 2.5% carbonyl-iron (iron overload [IO]) for 4 weeks. We show that Nrf2-/- mice develop an age-dependent cardiomyopathy, characterized by severe oxidation, degradation of SERCA2A and iron accumulation. This was associated with local hepcidin expression and increased serum non-transferrin-bound iron, which promotes maladaptive cardiac remodeling and interstitial fibrosis related to overactivation of the TGF-b pathway. When mice were exposed to IO diet, the absence of Nrf2 was paradoxically protective against further heart iron accumulation. Indeed, the combination of prolonged oxidation and the burst induced by IO diet resulted in activation of the unfolded protein response (UPR) system, which in turn promotes hepcidin expression independently from heart iron accumulation. In the heart of Hbbth3/+ mice, a model of b-thalassemia intermedia, despite the activation of Nrf2 pathway, we found severe protein oxidation, activation of UPR system and cardiac fibrosis independently from heart iron content. We describe the dual role of Nrf2 when aging is combined with IO and its novel interrelation with UPR system to ensure cell survival. We open a new perspective for early and intense treatment of cardiomyopathy in patients with b-thalassemia before the appearance of heart iron accumulation.


Assuntos
Cardiomiopatias , Sobrecarga de Ferro , Talassemia , Animais , Masculino , Camundongos , Cardiomiopatias/etiologia , Cardiomiopatias/genética , Cardiomiopatias/metabolismo , Hepcidinas , Ferro/metabolismo , Sobrecarga de Ferro/complicações , Sobrecarga de Ferro/genética , Sobrecarga de Ferro/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Qualidade de Vida , Talassemia/complicações , Talassemia/genética , Talassemia/metabolismo
9.
Genet Med ; 24(8): 1653-1663, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35511137

RESUMO

PURPOSE: Emerging evidence suggest that infection-dependent hyperactivation of complement system (CS) may worsen COVID-19 outcome. We investigated the role of predicted high impact rare variants - referred as qualifying variants (QVs) - of CS genes in predisposing asymptomatic COVID-19 in elderly individuals, known to be more susceptible to severe disease. METHODS: Exploiting exome sequencing data and 56 CS genes, we performed a gene-based collapsing test between 164 asymptomatic subjects (aged ≥60 years) and 56,885 European individuals from the Genome Aggregation Database. We replicated this test comparing the same asymptomatic individuals with 147 hospitalized patients with COVID-19. RESULTS: We found an enrichment of QVs in 3 genes (MASP1, COLEC11, and COLEC10), which belong to the lectin pathway, in the asymptomatic cohort. Analyses of complement activity in serum showed decreased activity of lectin pathway in asymptomatic individuals with QVs. Finally, we found allelic variants associated with asymptomatic COVID-19 phenotype and with a decreased expression of MASP1, COLEC11, and COLEC10 in lung tissue. CONCLUSION: This study suggests that genetic rare variants can protect from severe COVID-19 by mitigating the activity of lectin pathway and prothrombin. The genetic data obtained through ES of 786 asymptomatic and 147 hospitalized individuals are publicly available at http://espocovid.ceinge.unina.it/.


Assuntos
COVID-19 , Idoso , COVID-19/genética , Colectinas/genética , Colectinas/metabolismo , Células Germinativas , Humanos , Lectinas/genética , SARS-CoV-2 , Sequenciamento do Exoma
10.
Blood ; 136(11): 1274-1283, 2020 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-32702750

RESUMO

Congenital dyserythropoietic anemias (CDAs) are a heterogeneous group of inherited anemias that affect the normal differentiation-proliferation pathways of the erythroid lineage. They belong to the wide group of ineffective erythropoiesis conditions that mainly result in monolinear cytopenia. CDAs are classified into the 3 major types (I, II, III), plus the transcription factor-related CDAs, and the CDA variants, on the basis of the distinctive morphological, clinical, and genetic features. Next-generation sequencing has revolutionized the field of diagnosis of and research into CDAs, with reduced time to diagnosis, and ameliorated differential diagnosis in terms of identification of new causative/modifier genes and polygenic conditions. The main improvements regarding CDAs have been in the study of iron metabolism in CDAII. The erythroblast-derived hormone erythroferrone specifically inhibits hepcidin production, and its role in the mediation of hepatic iron overload has been dissected out. We discuss here the most recent advances in this field regarding the molecular genetics and pathogenic mechanisms of CDAs, through an analysis of the clinical and molecular classifications, and the complications and clinical management of patients. We summarize also the main cellular and animal models developed to date and the possible future therapies.


Assuntos
Anemia Diseritropoética Congênita/genética , Anemia Diseritropoética Congênita/classificação , Anemia Diseritropoética Congênita/diagnóstico , Anemia Diseritropoética Congênita/terapia , Animais , Transfusão de Sangue , Diagnóstico Diferencial , Modelos Animais de Doenças , Heterogeneidade Genética , Glicoproteínas/genética , Glicoproteínas/fisiologia , Transplante de Células-Tronco Hematopoéticas , Hepcidinas , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Hidropisia Fetal/diagnóstico , Hidropisia Fetal/etiologia , Sobrecarga de Ferro/etiologia , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/fisiologia , Camundongos , Camundongos Knockout , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/fisiologia , Técnicas de Diagnóstico Molecular , Proteínas Nucleares/genética , Proteínas Nucleares/fisiologia , Hormônios Peptídicos/fisiologia , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/fisiologia , Peixe-Zebra
11.
Haematologica ; 107(11): 2650-2660, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-35443560

RESUMO

Sickle cell disease (SCD) is an inherited red blood cell disorder that occurs worldwide. Acute vaso-occlusive crisis is the main cause of hospitalization in patients with SCD. There is growing evidence that inflammatory vasculopathy plays a key role in both acute and chronic SCD-related clinical manifestations. In a humanized mouse model of SCD, we found an increase of von Willebrand factor activity and a reduction in the ratio of a disintegrin and metalloproteinase with thrombospondin type 1 motif, number 13 (ADAMTS13) to von Willebrand factor activity similar to that observed in the human counterpart. Recombinant ADAMTS13 was administered to humanized SCD mice before they were subjected to hypoxia/reoxygenation (H/R) stress as a model of vaso-occlusive crisis. In SCD mice, recombinant ADAMTS13 reduced H/R-induced hemolysis and systemic and local inflammation in lungs and kidneys. It also diminished H/R-induced worsening of inflammatory vasculopathy, reducing local nitric oxidase synthase expression. Collectively, our data provide for the firsttime evidence that pharmacological treatment with recombinant ADAMTS13 (TAK-755) diminished H/R-induced sickle cell-related organ damage. Thus, recombinant ADAMTS13 might be considered as a potential effective disease-modifying treatment option for sickle cell-related acute events.


Assuntos
Proteína ADAMTS13 , Anemia Falciforme , Doenças Vasculares , Animais , Humanos , Camundongos , Proteína ADAMTS13/uso terapêutico , Anemia Falciforme/complicações , Anemia Falciforme/tratamento farmacológico , Modelos Animais de Doenças , Eritrócitos Anormais , Hipóxia , Doenças Vasculares/tratamento farmacológico , Doenças Vasculares/etiologia , Fator de von Willebrand , Proteínas Recombinantes/uso terapêutico
12.
Cancer Cell Int ; 22(1): 174, 2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35488346

RESUMO

BACKGROUND: FGFR1 regulates cell-cell adhesion and extracellular matrix architecture and acts as oncogene in several cancers. Potential cancer driver mutations of FGFR1 occur in neuroblastoma (NB), a neural crest-derived pediatric tumor arising in sympathetic nervous system, but so far they have not been studied experimentally. We investigated the driver-oncogene role of FGFR1 and the implication of N546K mutation in therapy-resistance in NB cells. METHODS: Public datasets were used to predict the correlation of FGFR1 expression with NB clinical outcomes. Whole genome sequencing data of 19 paired diagnostic and relapse NB samples were used to find somatic mutations. In NB cell lines, silencing by short hairpin RNA and transient overexpression of FGFR1 were performed to evaluate the effect of the identified mutation by cell growth, invasion and cologenicity assays. HEK293, SHSY5Y and SKNBE2 were selected to investigate subcellular wild-type and mutated protein localization. FGFR1 inhibitor (AZD4547), alone or in combination with PI3K inhibitor (GDC0941), was used to rescue malignant phenotypes induced by overexpression of FGFR1 wild-type and mutated protein. RESULTS: High FGFR1 expression correlated with low relapse-free survival in two independent NB gene expression datasets. In addition, we found the somatic mutation N546K, the most recurrent point mutation of FGFR1 in all cancers and already reported in NB, in one out of 19 matched primary and recurrent tumors. Loss of FGFR1 function attenuated invasion and cologenicity in NB cells, whereas FGFR1 overexpression enhanced oncogenicity. The overexpression of FGFR1N546K protein showed a higher nuclear localization compared to wild-type protein and increased cellular invasion and cologenicity. Moreover, N546K mutation caused the failure in response to treatment with FGFR1 inhibitor by activation of ERK, STAT3 and AKT pathways. The combination of FGFR1 and PI3K pathway inhibitors was effective in reducing the invasive and colonigenic ability of cells overexpressing FGFR1 mutated protein. CONCLUSIONS: FGFR1 is an actionable driver oncogene in NB and a promising therapy may consist in targeting FGFR1 mutations in patients with therapy-resistant NB.

13.
Int J Mol Sci ; 23(3)2022 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-35163229

RESUMO

Biallelic pathogenic variants in the SEC23B gene cause congenital dyserythropoietic anemia type II (CDA II), a rare hereditary disorder hallmarked by ineffective erythropoiesis, hemolysis, erythroblast morphological abnormalities, and hypo-glycosylation of some red blood cell membrane proteins. Abnormalities in SEC23B, which encodes the homonymous cytoplasmic COPII (coat protein complex II) component, disturb the endoplasmic reticulum to Golgi trafficking and affect different glycosylation pathways. The most harmful complication of CDA II is the severe iron overload. Within our case series (28 CDA II patients), approximately 36% of them exhibit severe iron overload despite mild degree of anemia and slightly increased levels of ERFE (the only erythroid regulator of hepcidin suppression). Thus, we hypothesized a direct role of SEC23B loss-of-function in the pathomechanism of hepatic iron overload. We established a hepatic cell line, HuH7, stably silenced for SEC23B. In silenced cells, we observed significant alterations of the iron status, due to both the alteration in BMP/SMADs pathway effectors and a reduced capability to sense BMP6 stimulus. We demonstrated that the loss-of-function of SEC23B is responsible of the impairment in glycosylation of the membrane proteins involved in the activation of the BMP/SMADs pathway with subsequent hepcidin suppression. Most of these data were confirmed in another hepatic cell line, HepG2, stably silenced for SEC23B. Our findings suggested that the pathogenic mechanism of iron overload in CDA II is associated to both ineffective erythropoiesis and to a specific involvement of SEC23B pathogenic variants at hepatic level. Finally, we demonstrated the ability of SEC23B paralog, i.e., SEC23A, to rescue the hepcidin suppression, highlighting the functional overlap between the two SEC23 paralogs in human hepatic cells.


Assuntos
Hepatócitos/metabolismo , Hepcidinas/genética , Proteínas de Transporte Vesicular/metabolismo , Linhagem Celular , Retículo Endoplasmático/metabolismo , Eritropoese/genética , Glicosilação , Complexo de Golgi/metabolismo , Hepcidinas/metabolismo , Humanos , Sobrecarga de Ferro/genética , Sobrecarga de Ferro/metabolismo , Fígado/patologia , Mutação com Perda de Função/genética , Fenótipo , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/fisiologia
14.
Blood ; 133(3): 252-265, 2019 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-30404812

RESUMO

Resolvins (Rvs), endogenous lipid mediators, play a key role in the resolution of inflammation. Sickle cell disease (SCD), a genetic disorder of hemoglobin, is characterized by inflammatory and vaso-occlusive pathologies. We document altered proresolving events following hypoxia/reperfusion in humanized SCD mice. We demonstrate novel protective actions of 17R-resolvin D1 (17R-RvD1; 7S, 8R, 17R-trihydroxy-4Z, 9E, 11E, 13Z, 15E, 19Z-docosahexaenoic acid) in reducing ex vivo human SCD blood leukocyte recruitment by microvascular endothelial cells and in vivo neutrophil adhesion and transmigration. In SCD mice exposed to hypoxia/reoxygenation, oral administration of 17R -RvD1 reduces systemic/local inflammation and vascular dysfunction in lung and kidney. The mechanism of action of 17R-RvD1 involves (1) enhancement of SCD erythrocytes and polymorphonuclear leukocyte efferocytosis, (2) blunting of NF-κB activation, and (3) a reduction in inflammatory cytokines, vascular activation markers, and E-selectin expression. Thus, 17R-RvD1 might represent a new therapeutic strategy for the inflammatory vasculopathy of SCD.


Assuntos
Anemia Falciforme/complicações , Anti-Inflamatórios não Esteroides/administração & dosagem , Ácidos Docosa-Hexaenoicos/administração & dosagem , Nefropatias/prevenção & controle , Pneumonia/prevenção & controle , Animais , Citocinas/metabolismo , Humanos , Nefropatias/etiologia , Nefropatias/patologia , Camundongos , Neutrófilos/imunologia , Neutrófilos/metabolismo , Neutrófilos/patologia , Pneumonia/etiologia , Pneumonia/patologia
15.
Am J Hematol ; 96(12): 1666-1678, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34467556

RESUMO

Methemoglobinemia is a rare disorder associated with oxidization of divalent ferro-iron of hemoglobin (Hb) to ferri-iron of methemoglobin (MetHb). Methemoglobinemia can result from either inherited or acquired processes. Acquired forms are the most common, mainly due to the exposure to substances that cause oxidation of the Hb both directly or indirectly. Inherited forms are due either to autosomal recessive variants in the CYB5R3 gene or to autosomal dominant variants in the globin genes, collectively known as HbM disease. Our recommendations are based on a systematic literature search. A series of questions regarding the key signs and symptoms, the methods for diagnosis, the clinical management in neonatal/childhood/adulthood period, and the therapeutic approach of methemoglobinemia were formulated and the relative recommendations were produced. An agreement was obtained using a Delphi-like approach and the experts panel reached a final consensus >75% of agreement for all the questions.


Assuntos
Metemoglobinemia/diagnóstico , Metemoglobinemia/terapia , Consenso , Diagnóstico Diferencial , Gerenciamento Clínico , Humanos , Metemoglobinemia/fisiopatologia
16.
Nature ; 528(7582): 418-21, 2015 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-26560027

RESUMO

Neuroblastoma is a paediatric malignancy that typically arises in early childhood, and is derived from the developing sympathetic nervous system. Clinical phenotypes range from localized tumours with excellent outcomes to widely metastatic disease in which long-term survival is approximately 40% despite intensive therapy. A previous genome-wide association study identified common polymorphisms at the LMO1 gene locus that are highly associated with neuroblastoma susceptibility and oncogenic addiction to LMO1 in the tumour cells. Here we investigate the causal DNA variant at this locus and the mechanism by which it leads to neuroblastoma tumorigenesis. We first imputed all possible genotypes across the LMO1 locus and then mapped highly associated single nucleotide polymorphism (SNPs) to areas of chromatin accessibility, evolutionary conservation and transcription factor binding sites. We show that SNP rs2168101 G>T is the most highly associated variant (combined P = 7.47 × 10(-29), odds ratio 0.65, 95% confidence interval 0.60-0.70), and resides in a super-enhancer defined by extensive acetylation of histone H3 lysine 27 within the first intron of LMO1. The ancestral G allele that is associated with tumour formation resides in a conserved GATA transcription factor binding motif. We show that the newly evolved protective TATA allele is associated with decreased total LMO1 expression (P = 0.028) in neuroblastoma primary tumours, and ablates GATA3 binding (P < 0.0001). We demonstrate allelic imbalance favouring the G-containing strand in tumours heterozygous for this SNP, as demonstrated both by RNA sequencing (P < 0.0001) and reporter assays (P = 0.002). These findings indicate that a recently evolved polymorphism within a super-enhancer element in the first intron of LMO1 influences neuroblastoma susceptibility through differential GATA transcription factor binding and direct modulation of LMO1 expression in cis, and this leads to an oncogenic dependency in tumour cells.


Assuntos
Proteínas de Ligação a DNA/genética , Elementos Facilitadores Genéticos/genética , Predisposição Genética para Doença/genética , Proteínas com Domínio LIM/genética , Neuroblastoma/genética , Polimorfismo de Nucleotídeo Único/genética , Fatores de Transcrição/genética , Acetilação , Alelos , Desequilíbrio Alélico , Sítios de Ligação , Epigenômica , Fator de Transcrição GATA3/metabolismo , Regulação Neoplásica da Expressão Gênica/genética , Estudo de Associação Genômica Ampla , Genótipo , Histonas/química , Histonas/metabolismo , Humanos , Íntrons/genética , Lisina/metabolismo , Especificidade de Órgãos , Reprodutibilidade dos Testes
17.
Hemoglobin ; 45(6): 351-354, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31829079

RESUMO

We describe a novel deletion causing heterozygous εγδß-thalassemia (εγδß-thal) across three generations of a Greek family. The Greek deletion is about 72 kb in length, spanning from the hypersensitive site 4 (HS4) in the locus control region (LCR) to the 3' end of the ß-globin gene, thus encompassing the entire ß-globin gene cluster. The deletion caused severe but transient neonatal anemia and a non transfusion-dependent chronic hemolytic anemia state later in life, resembling mild ß-thalassemia intermedia (ß-TI) rather than ß-thalassemia (ß-thal) trait, as had been previously reported. Apart from the presentation of clinical and laboratory characteristics, the challenges involving clinical management are also discussed.


Assuntos
Talassemia , Talassemia beta , Grécia , Humanos , Fenótipo , Talassemia/genética , Globinas beta/genética , Talassemia beta/diagnóstico , Talassemia beta/genética
18.
Int J Mol Sci ; 22(10)2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-34065289

RESUMO

Genome-wide association studies (GWAS) found locus 3p21.31 associated with severe COVID-19. CCR5 resides at the same locus and, given its known biological role in other infection diseases, we investigated if common noncoding and rare coding variants, affecting CCR5, can predispose to severe COVID-19. We combined single nucleotide polymorphisms (SNPs) that met the suggestive significance level (P ≤ 1 × 10-5) at the 3p21.31 locus in public GWAS datasets (6406 COVID-19 hospitalized patients and 902,088 controls) with gene expression data from 208 lung tissues, Hi-C, and Chip-seq data. Through whole exome sequencing (WES), we explored rare coding variants in 147 severe COVID-19 patients. We identified three SNPs (rs9845542, rs12639314, and rs35951367) associated with severe COVID-19 whose risk alleles correlated with low CCR5 expression in lung tissues. The rs35951367 resided in a CTFC binding site that interacts with CCR5 gene in lung tissues and was confirmed to be associated with severe COVID-19 in two independent datasets. We also identified a rare coding variant (rs34418657) associated with the risk of developing severe COVID-19. Our results suggest a biological role of CCR5 in the progression of COVID-19 as common and rare genetic variants can increase the risk of developing severe COVID-19 by affecting the functions of CCR5.


Assuntos
COVID-19/genética , COVID-19/metabolismo , Predisposição Genética para Doença , Receptores CCR5/genética , Receptores CCR5/metabolismo , Alelos , Brônquios/metabolismo , Brônquios/patologia , Brônquios/virologia , COVID-19/fisiopatologia , Cromossomos Humanos/genética , Estudos de Coortes , Biologia Computacional , Bases de Dados Genéticas , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Pulmão/metabolismo , Pulmão/patologia , Pulmão/virologia , Polimorfismo de Nucleotídeo Único , Sequenciamento do Exoma
19.
Carcinogenesis ; 41(3): 284-295, 2020 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-31605138

RESUMO

Neuroblastoma (NB) and malignant cutaneous melanoma (CMM) are neural crest cells (NCC)-derived tumors and may have a shared genetic basis, but this has not been investigated systematically by genome-wide association studies (GWAS). We took a three-staged approach to conduct cross-disease meta-analysis of GWAS for NB and CMM (2101 NB cases and 4202 controls; 12 874 CMM cases and 23 203 controls) to identify shared loci. Findings were replicated in 1403 NB cases and 1403 controls of European ancestry and in 636 NB, 508 CMM cases and 2066 controls of Italian origin. We found a cross-association at locus 1p13.2 (rs2153977, odds ratio = 0.91, P = 5.36 × 10-8). We also detected a suggestive (P < 10-7) NB-CMM cross-association at 2q37.1 with opposite effect on cancer risk. Pathway analysis of 110 NB-CMM risk loci with P < 10-4 demonstrated enrichment of biological processes such as cell migration, cell cycle, metabolism and immune response, which are essential of human NCC development, underlying both tumors. In vitro and in silico analyses indicated that the rs2153977-T protective allele, located in an NB and CMM enhancer, decreased expression of SLC16A1 via long-range loop formation and altered a T-box protein binding site. Upon depletion of SLC16A1, we observed a decrease of cellular proliferation and invasion in both NB and CMM cell lines, suggesting its role as oncogene. This is the largest study to date examining pleiotropy across two NC cell-derived tumors identifying 1p13.2 as common susceptibility locus for NB and CMM risk. We demonstrate that combining genome-wide association studies results across cancers with same origins can identify new loci common to neuroblastoma and melanoma arising from tissues which originate from neural crest cells. Our results also show 1p13.2 confer risk to neuroblastoma and melanoma by regulating SLC16A1.


Assuntos
Neoplasias das Glândulas Suprarrenais/genética , Melanoma/genética , Transportadores de Ácidos Monocarboxílicos/genética , Neuroblastoma/genética , Neoplasias Cutâneas/genética , Simportadores/genética , Neoplasias das Glândulas Suprarrenais/patologia , Diferenciação Celular/genética , Movimento Celular/genética , Cromossomos Humanos Par 1/genética , Feminino , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Masculino , Melanoma/patologia , Crista Neural/patologia , Neuroblastoma/patologia , Polimorfismo de Nucleotídeo Único/genética , Neoplasias Cutâneas/patologia , Melanoma Maligno Cutâneo
20.
J Cell Mol Med ; 24(11): 6459-6471, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32336043

RESUMO

Neuroblastoma (NB) is the most common extracranial neoplasm in children. The overall outcome for high-risk NB patients is still unacceptable, therefore, it is critical to deeply understand molecular mechanisms associated with NB, which in turn can be utilized for developing drugs towards the treatment of NB. Protein kinases (TKs) play an essential role in the regulation of cell survival and proliferation. Different kinases, such as anaplastic lymphoma kinase (ALK), Aurora kinase, RET receptor tyrosine kinase, are potential therapeutic targets in various cancers, including NB. We analysed a cohort of 45 high-risk NB patients and 9 NB cell lines by a targeted-(t)NGS custom gene panel (genes codifying for the kinase domains of 90 TKs). We identified somatic variants in four TK genes (ALK, EPHB4, LMTK3 and EPHB6) in NB patients and we functionally characterized an interesting somatic variant, V871I, in EPHB4 gene. EPHB4 plays a crucial role in cardiovascular development and regulates vascularization in cancer-promoting angiogenesis, tumour growth and metastasis. Several EPHB4 mutations have previously been identified in solid and haematological tumour specimens but EPHB4 mutations were not described until now in NB. Interestingly, a re-analysis of public CGH-array showed that the EPHB4 gain is associated with advanced diseases in NB. We further demonstrated that higher EPHB4 expression is correlated to stage 4 of NB and with poor overall survival. Additionally, we also revealed that the EPHB4-V871I accounts for increased proliferation, migration and invasion properties in two NB cell lines by acting on VEGF, c-RAF and CDK4 target genes and by increasing the phosphorylation of ERK1-2 pathway. The use of two EPHB4 inhibitors, JI-101 and NVP-BHG712, was able to rescue the phenotype driven by the variant. Our study suggested that EPHB4 is a promising therapeutic target in high-risk NB.


Assuntos
Mutação/genética , Neuroblastoma/genética , Receptor EphB4/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Humanos , Metástase Neoplásica/genética , Metástase Neoplásica/patologia , Neovascularização Patológica/genética , Neovascularização Patológica/patologia , Neuroblastoma/patologia , Proteínas Quinases/genética , Transdução de Sinais/genética
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