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1.
J Med Case Rep ; 18(1): 166, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38589931

RESUMO

BACKGROUND: Fructose-1,6-bisphosphatase deficiency is a rare autosomal recessive disorder characterized by impaired gluconeogenesis. Fructose-1,6-bisphosphatase 1 (FBP1) mutations demonstrate ethnic patterns. For instance, Turkish populations commonly harbor exon 2 deletions. We present a case report of whole exon 2 deletion in a Syrian Arabian child as the first recording of this mutation among Arabian ethnicity and the first report of FBP1 gene mutation in Syria. CASE PRESENTATION: We present the case of a 2.5-year-old Syrian Arab child with recurrent hypoglycemic episodes, accompanied by nausea and lethargy. The patient's history, physical examination, and laboratory findings raised suspicion of fructose-1,6-bisphosphatase deficiency. Whole exome sequencing was performed, revealing a homozygous deletion of exon 2 in the FBP1 gene, confirming the diagnosis. CONCLUSION: This case highlights a potential novel mutation in the Arab population; this mutation is well described in the Turkish population, which suggests potential shared mutations due to ancestral relationships between the two ethnicities. Further studies are needed to confirm this finding.


Assuntos
Deficiência de Frutose-1,6-Difosfatase , Pré-Escolar , Humanos , Documentação , Etnicidade , Frutose , Deficiência de Frutose-1,6-Difosfatase/complicações , Deficiência de Frutose-1,6-Difosfatase/diagnóstico , Deficiência de Frutose-1,6-Difosfatase/genética , Frutose-Bifosfatase/genética , Homozigoto , Mutação , Deleção de Sequência
2.
Proc Natl Acad Sci U S A ; 121(16): e2315541121, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38598341

RESUMO

Ferroptosis is an iron-dependent type of regulated cell death resulting from extensive lipid peroxidation and plays a critical role in various physiological and pathological processes. However, the regulatory mechanisms for ferroptosis sensitivity remain incompletely understood. Here, we report that homozygous deletion of Usp8 (ubiquitin-specific protease 8) in intestinal epithelial cells (IECs) leads to architectural changes in the colonic epithelium and shortens mouse lifespan accompanied by increased IEC death and signs of lipid peroxidation. However, mice with heterozygous deletion of Usp8 in IECs display normal phenotype and become resistant to azoxymethane/dextran sodium sulfate-induced colorectal tumorigenesis. Mechanistically, USP8 interacts with and deubiquitinates glutathione peroxidase 4 (GPX4), leading to GPX4 stabilization. Thus, USP8 inhibition destabilizes GPX4 and sensitizes cancer cells to ferroptosis in vitro. Notably, USP8 inhibition in combination with ferroptosis inducers retards tumor growth and enhances CD8+ T cell infiltration, which potentiates tumor response to anti-PD-1 immunotherapy in vivo. These findings uncover that USP8 counteracts ferroptosis by stabilizing GPX4 and highlight targeting USP8 as a potential therapeutic strategy to boost ferroptosis for enhancing cancer immunotherapy.


Assuntos
Ferroptose , Neoplasias , Camundongos , Animais , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Ferroptose/genética , Homozigoto , Deleção de Sequência , Peroxidação de Lipídeos , Homeostase , Neoplasias/genética , Neoplasias/terapia , Imunoterapia
3.
Microbiology (Reading) ; 170(4)2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38602388

RESUMO

Since the 1980s, chromosome-integration vectors have been used as a core method of engineering Bacillus subtilis. One of the most frequently used vector backbones contains chromosomally derived regions that direct homologous recombination into the amyE locus. Here, we report a gap in the homology region inherited from the original amyE integration vector, leading to erroneous recombination in a subset of transformants and a loss-of-function mutation in the downstream gene. Internal to the homology arm that spans the 3' portion of amyE and the downstream gene ldh, an unintentional 227 bp deletion generates two crossover events. The major event yields the intended genotype, but the minor event, occurring in ~10 % of colonies, results in a truncation of ldh, which encodes lactate dehydrogenase. Although both types of colonies test positive for amyE disruption by starch plating, the potential defect in fermentative metabolism may be left undetected and confound the results of subsequent experiments.


Assuntos
Bacillus subtilis , Cromossomos , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Mutação , Deleção de Sequência
4.
Reprod Toxicol ; 125: 108574, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38462212

RESUMO

The GSTT1 and GSTM1 genes have a role in mercury metabolism and excretion, as well as blood pressure response, impacting birth outcomes. The present study assesses whether GSTT1 and GSTM1 deletion variants and maternal hair Hg concentration are associated with blood pressure and birth outcomes among the Indonesian coastal pregnant mother population. A cross-sectional study was conducted on 139 pregnant women in the Jepara coastal area of Central Java, Indonesia. Maternal characteristics during pregnancy, including blood pressure and birth outcomes, were collected. GSTT1 and GSTM1 gene variants were detected using polymerase chain reaction (PCR). Hair Hg levels were measured using the reducing-vaporization mercury analyzer. The mean maternal hair Hg concentration was 0.727±0.558 µg/g. GSTT1 genotype homozygous deletion was found in 41.7% of subjects, while no GSTM1 deletion was found. No statistically significant difference was found between deletion and non-deletion groups for hair Hg. GSTT1 deletion genotype shows protection but is inconclusive toward diastolic hypertension (p=0.048, OR 0.285, CI 0.077-1.052) and insignificant with birth outcomes (all p>0.05). High hair Hg concentration and positive history of cardiovascular diseases increase the risk of systolic and diastolic hypertension during pregnancy with OR 6.871 (CI 95% 1.445-32.660) and 8.518 (CI 95% 2.126-34.125), respectively, while not in birth outcomes. Maternal Hg exposure and history of cardiovascular diseases are independent risk factors for pregnant hypertension, whereas the GSTT1 homozygous deletion genotype has no role in diastolic hypertension and birth outcomes among the Indonesian coastal pregnant mother population.


Assuntos
Doenças Cardiovasculares , Hipertensão , Mercúrio , Humanos , Feminino , Gravidez , Indonésia/epidemiologia , Gestantes , Homozigoto , Pressão Sanguínea , Estudos Transversais , Polimorfismo Genético , Deleção de Sequência , Genótipo , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Hipertensão/genética , Cabelo , Predisposição Genética para Doença , Estudos de Casos e Controles
5.
Genes (Basel) ; 15(3)2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38540372

RESUMO

In newborn screening (NBS), it is important to consider the availability of multiplex assays or other tests that can be integrated into existing systems when attempting to implement NBS for new target diseases. Recent developments in innovative testing technology have made it possible to simultaneously screen for severe primary immunodeficiency (PID) and spinal muscular atrophy (SMA) using quantitative real-time polymerase chain reaction (qPCR) assays. We describe our experience of optional NBS for severe PID and SMA in Osaka, Japan. A multiplex TaqMan qPCR assay was used for the optional NBS program. The assay was able to quantify the levels of T-cell receptor excision circles and kappa-deleting recombination excision circles, which is useful for severe combined immunodeficiency and B-cell deficiency screening, and can simultaneously detect the homozygous deletion of SMN1 exon 7, which is useful for NBS for SMA. In total, 105,419 newborns were eligible for the optional NBS program between 1 August 2020 and 31 August 2023. A case each of X-linked agammaglobulinemia and SMA were diagnosed through the optional NBS and treated at early stages (before symptoms appeared). Our results show how multiplex PCR-based NBS can benefit large-scale NBS implementation projects for new target diseases.


Assuntos
Atrofia Muscular Espinal , Triagem Neonatal , Recém-Nascido , Humanos , Triagem Neonatal/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Homozigoto , Japão , Deleção de Sequência , Atrofia Muscular Espinal/diagnóstico , Atrofia Muscular Espinal/genética
6.
Int J Mol Sci ; 25(5)2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38473983

RESUMO

Asians have a higher carrier rate of pulmonary arterial hypertension (PAH)-related genetic variants than Caucasians do. This study aimed to identify PAH-related genetic variants using whole exome sequencing (WES) in Asian idiopathic and heritable PAH cohorts. A WES library was constructed, and candidate variants were further validated by polymerase chain reaction and Sanger sequencing in the PAH cohort. In a total of 69 patients, the highest incidence of variants was found in the BMPR2, ATP13A3, and GDF2 genes. Regarding the BMPR2 gene variants, there were two nonsense variants (c.994C>T, p. Arg332*; c.1750C>T, p. Arg584*), one missense variant (c.1478C>T, p. Thr493Ile), and one novel in-frame deletion variant (c.877_888del, p. Leu293_Ser296del). Regarding the GDF2 variants, there was one likely pathogenic nonsense variant (c.259C>T, p. Gln87*) and two missense variants (c.1207G>A, p. Val403Ile; c.38T>C, p. Leu13Pro). The BMPR2 and GDF2 variant subgroups had worse hemodynamics. Moreover, the GDF2 variant patients were younger and had a significantly lower GDF2 value (135.6 ± 36.2 pg/mL, p = 0.002) in comparison to the value in the non-BMPR2/non-GDF2 mutant group (267.8 ± 185.8 pg/mL). The BMPR2 variant carriers had worse hemodynamics compared to the patients with the non-BMPR2/non-GDF2 mutant group. Moreover, there was a significantly lower GDF2 value in the GDF2 variant carriers compared to the control group. GDF2 may be a protective or corrected modifier in certain genetic backgrounds.


Assuntos
Hipertensão Arterial Pulmonar , Humanos , Hipertensão Arterial Pulmonar/genética , Hipertensão Pulmonar Primária Familiar/genética , Mutação de Sentido Incorreto , Hemodinâmica , Deleção de Sequência , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/genética , Mutação , Adenosina Trifosfatases/genética , Proteínas de Membrana Transportadoras/genética , Fator 2 de Diferenciação de Crescimento/genética
7.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 41(2): 193-198, 2024 Feb 10.
Artigo em Chinês | MEDLINE | ID: mdl-38311558

RESUMO

OBJECTIVE: To explore the genetic etiology of a child with delayed growth and development and carry out a literature review. METHODS: A child suspected for Al Kaissi syndrome at the First Affiliated Hospital of Zhengzhou University on March 6, 2021 was selected as the study subject. Following extraction of genomic DNA, the child was subjected to copy number variation sequencing (CNV-seq) and whole exome sequencing (WES), and candidate variants were verified by PCR-agarose gel electrophoresis and quantitative real-time PCR (qPCR). Prenatal diagnosis was conducted on chorionic villi sample upon subsequent pregnancy. RESULTS: The child, a 6-year-and-4-month-old boy, has dysmorphic features including low-set protruding ears and triangular face, delayed language and intellectual development, and ventricular septal defect. CNV-seq result has found no obvious abnormality, whilst WES revealed homozygous deletion of exons 1 and 2 of the CDK10 gene, which was confirmed by PCR-agarose gel electrophoresis and qPCR. Both of his parents were heterozygous carriers. Prenatal diagnosis using chorionic villi samples suggested that the fetus also carried the heterozygous deletion. CONCLUSION: The clinical features of Al Kaissi syndrome in this child can probably be attributed to the homozygous deletion of exons 1 and 2 of the CDK10 gene.


Assuntos
Variações do Número de Cópias de DNA , Diagnóstico Pré-Natal , Criança , Feminino , Humanos , Masculino , Gravidez , Quinases Ciclina-Dependentes/genética , Éxons , Homozigoto , Deleção de Sequência
8.
mSphere ; 9(3): e0069623, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38376217

RESUMO

Fungal infections cause a large health burden but are treated by only a handful of antifungal drug classes. Chromatin factors have emerged as possible targets for new antifungals. These targets include the reader proteins, which interact with posttranslationally modified histones to influence DNA transcription and repair. The YEATS domain is one such reader recognizing both crotonylated and acetylated histones. Here, we performed a detailed structure/function analysis of the Candida albicans YEATS domain reader Yaf9, a subunit of the NuA4 histone acetyltransferase and the SWR1 chromatin remodeling complex. We have previously demonstrated that the homozygous deletion mutant yaf9Δ/Δ displays growth defects and is avirulent in mice. Here we show that a YEATS domain mutant expected to inactivate Yaf9's chromatin binding does not display strong phenotypes in vitro, nor during infection of immune cells or in a mouse systemic infection model, with only a minor virulence reduction in vivo. In contrast to the YEATS domain mutation, deletion of the C-terminal domain of Yaf9, a protein-protein interaction module necessary for its interactions with SWR1 and NuA4, phenocopies the null mutant. This shows that the C-terminal domain is essential for Yaf9 roles in vitro and in vivo, including C. albicans virulence. Our study informs on the strategies for therapeutic targeting of Yaf9, showing that approaches taken for the mammalian YEATS domains by disrupting their chromatin binding might not be effective in C. albicans, and provides a foundation for studying YEATS proteins in human fungal pathogens.IMPORTANCEThe scarcity of available antifungal drugs and rising resistance demand the development of therapies with new modes of action. In this context, chromatin regulation may be a target for novel antifungal therapeutics. To realize this potential, we must better understand the roles of chromatin regulators in fungal pathogens. Toward this goal, here, we studied the YEATS domain chromatin reader Yaf9 in Candida albicans. Yaf9 uses the YEATS domain for chromatin binding and a C-terminal domain to interact with chromatin remodeling complexes. By constructing mutants in these domains and characterizing their phenotypes, our data indicate that the Yaf9 YEATS domain might not be a suitable therapeutic drug target. Instead, the Yaf9 C-terminal domain is critical for C. albicans virulence. Collectively, our study informs how a class of chromatin regulators performs their cellular and pathogenesis roles in C. albicans and reveals strategies to inhibit them.


Assuntos
Cromatina , Proteínas de Saccharomyces cerevisiae , Humanos , Animais , Camundongos , Cromatina/genética , Histonas/genética , Candida albicans/genética , Candida albicans/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Antifúngicos , Homozigoto , Deleção de Sequência , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Domínios e Motivos de Interação entre Proteínas , Mamíferos
9.
BMC Pulm Med ; 24(1): 91, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38383302

RESUMO

BACKGROUND: Alpha1-antitrypsin (AAT) is a serine protease inhibitor that serves as a counterbalance to the activity of elastases, e.g., neutrophil elastase in lung tissue. AAT deficiency (AATD) is a rare disorder usually arising from mutations to the SERPINA1 gene that codes for AAT. The most common AATD alleles are S and Z which produce ~ 40% and ~ 90% reductions in serum AAT, respectively. Rare genetic variants (> 500 identified) can also be associated with mild to severe AATD. RESULTS: This report describes a novel mutation of SERPINA1 producing AATD, which we have designated, Q0RIZE. This mutation was identified in a 44-year-old woman admitted with massive hemoptysis and treated with bronchial artery embolization. Computed tomography revealed centriacinar and panacinar emphysema with prominent air entrapment, atelectasis, and localized bronchiectasis. Serum AAT was < 0.27 g/L (below detection limit). Genetic analysis showed homozygous deletion of exons I to III. CONCLUSIONS: Although many SERPINA1 variants have been identified, variants with large deletions and identified in a homozygous individual, as seen in this case with Q0RIZE, are uncommon. AATD is an underdiagnosed and undertreated disease. Wider screening of COPD patients could result in earlier diagnosis and treatment that could preserve lung function.


Assuntos
Deficiência de alfa 1-Antitripsina , Feminino , Humanos , Adulto , Deficiência de alfa 1-Antitripsina/diagnóstico , Deficiência de alfa 1-Antitripsina/genética , Deficiência de alfa 1-Antitripsina/complicações , Homozigoto , Turquia , Deleção de Sequência , alfa 1-Antitripsina/genética , Pulmão/diagnóstico por imagem
10.
Pediatr Neurol ; 152: 200-208, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38306901

RESUMO

BACKGROUND: Fatty acid 2-hydroxylase (FA2H) is encoded by the FA2H gene, with mutations therein leading to the neurodegenerative condition, spastic paraplegia-35 (SPG35). We aim to elucidate the genetic underpinnings of a nonconsanguineous Chinese family diagnosed with SPG35 by examining the clinical manifestations, scrutinizing genetic variants, and establishing the role of FA2H mutation in lipid metabolism. METHODS: Using next-generation sequencing analysis to identify the pathogenic gene in this pedigree and family cosegregation verification. The use of lipidomics of patient pedigree peripheral blood mononuclear cells further substantiated alterations in lipid metabolism attributable to the FA2H exon 1 deletion. RESULTS: The proband exhibited gait disturbance from age 5 years; he developed further clinical manifestations such as scissor gait and dystonia. His younger sister also presented with a spastic gait from the same age. We identified a homozygous deletion in the region of FA2H exon 1, spanning from chr16:74807867 to chr16: 74810391 in the patients. Lipidomic analysis revealed significant differences in 102 metabolites compared with healthy controls, with 62 metabolites increased and 40 metabolites decreased. We specifically zeroed in on 19 different sphingolipid metabolites, which comprised ceramides, ganglioside, etc., with only three of these sphingolipids previously reported. CONCLUSIONS: This is the first study of lipid metabolism in the blood of patients with SPG35. The results broaden our understanding of the SPG35 gene spectrum, offering insights for future molecular mechanism research and laying groundwork for determining metabolic markers.


Assuntos
Transtornos Heredodegenerativos do Sistema Nervoso , Lipidômica , Paraplegia Espástica Hereditária , Masculino , Humanos , Pré-Escolar , Homozigoto , Leucócitos Mononucleares/patologia , Deleção de Sequência/genética , Mutação , Éxons/genética , Linhagem , Paraplegia Espástica Hereditária/genética , Paraplegia Espástica Hereditária/diagnóstico , Paraplegia
11.
Int J Mol Sci ; 25(4)2024 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-38397078

RESUMO

Hanseniaspora uvarum is the predominant yeast species in the majority of wine fermentations, which has only recently become amenable to directed genetic manipulation. The genetics and metabolism of H. uvarum have been poorly studied as compared to other yeasts of biotechnological importance. This work describes the construction and characterization of homozygous deletion mutants in the HuZWF1 gene, encoding glucose-6-phosphate dehydrogenase (G6PDH), which provides the entrance into the oxidative part of the pentose phosphate pathway (PPP) and serves as a major source of NADPH for anabolic reactions and oxidative stress response. Huzwf1 deletion mutants grow more slowly on glucose medium than wild-type and are hypersensitive both to hydrogen peroxide and potassium bisulfite, indicating that G6PDH activity is required to cope with these stresses. The mutant also requires methionine for growth. Enzyme activity can be restored by the expression of heterologous G6PDH genes from other yeasts and humans under the control of a strong endogenous promoter. These findings provide the basis for a better adaptation of H. uvarum to conditions used in wine fermentations, as well as its use for other biotechnological purposes and as an expression organism for studying G6PDH functions in patients with hemolytic anemia.


Assuntos
Hanseniaspora , Vinho , Humanos , Fermentação , Glucosefosfato Desidrogenase/genética , Glucosefosfato Desidrogenase/metabolismo , Hanseniaspora/enzimologia , Homozigoto , Deleção de Sequência
12.
Nucleic Acids Res ; 52(6): 3199-3212, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38407436

RESUMO

Productive infections by RNA viruses require faithful replication of the entire genome. Yet many RNA viruses also produce deletion-containing viral genomes (DelVGs), aberrant replication products with large internal deletions. DelVGs interfere with the replication of wild-type virus and their presence in patients is associated with better clinical outcomes. The DelVG RNA itself is hypothesized to confer this interfering activity. DelVGs antagonize replication by out-competing the full-length genome and triggering innate immune responses. Here, we identify an additionally inhibitory mechanism mediated by a new class of viral proteins encoded by DelVGs. We identified hundreds of cryptic viral proteins translated from DelVGs. These DelVG-encoded proteins (DPRs) include canonical viral proteins with large internal deletions, as well as proteins with novel C-termini translated from alternative reading frames. Many DPRs retain functional domains shared with their full-length counterparts, suggesting they may have activity during infection. Mechanistic studies of DPRs derived from the influenza virus protein PB2 showed that they poison replication of wild-type virus by acting as dominant-negative inhibitors of the viral polymerase. These findings reveal that DelVGs have a dual inhibitory mechanism, acting at both the RNA and protein level. They further show that DPRs have the potential to dramatically expand the functional proteomes of diverse RNA viruses.


Assuntos
Genoma Viral , Vírus da Influenza A , Proteoma , Proteínas Virais , Humanos , Genoma Viral/genética , Vírus da Influenza A/genética , Proteoma/genética , RNA Viral/genética , RNA Viral/metabolismo , Proteínas Virais/genética , Proteínas Virais/metabolismo , Replicação Viral/genética , Deleção de Sequência/genética , Animais , Cães , Linhagem Celular
13.
Mod Pathol ; 37(3): 100420, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38185249

RESUMO

9p21 deletions involving MTAP/CDKN2A genes are detected in diffuse pleural mesotheliomas (DPM) but are absent in benign mesothelial proliferations. Loss of MTAP expression by immunohistochemistry (IHC) is well accepted as a surrogate for 9p21 deletion to support a diagnosis of DPM. Accurate interpretation can be critical in the diagnosis of DPM, but variations in antibody performance may impact interpretation. The objectives of this study were to compare the performance of MTAP monoclonal antibodies (mAbs) EPR6893 and 1813 and to compare MTAP expression by IHC with 9p21 copy number status in DPM. Cytoplasmic expression of MTAP IHC with mAbs EPR6893 (ab126770; Abcam) and 1813 (NBP2-75730, Novus Biologicals) was evaluated in 56 DPM (47 epithelioid, 7 biphasic, and 2 sarcomatoid) profiled by targeted next-generation sequencing. 9p21 Copy number status was assessed by Fraction and Allele-Specific Copy Number Estimates from Tumor Sequencing (FACETS) analysis and also by CDKN2A fluorescence in situ hybridization in discrepant cases when material was available. MTAP mAb 1813 showed stronger immunoreactivity, more specific staining, and no equivocal interpretations compared to mAb EPR6893 which showed equivocal staining in 19 (34%) of cases due to weak or heterogenous immunoreactivity, lack of definitive internal positive control, and/or nonspecific background staining. MTAP expression with mAb 1813 showed near perfect agreement with 9p21 copy number by combined FACETS/fluorescence in situ hybridization calls (κ = 0.85; 95% CI, 0.71-0.99; P < .001). MTAP IHC with mAb 1813 was 96% sensitive, 86% specific, and 93% accurate for 9p21 homozygous deletion. The findings of this study suggest that interpretation of MTAP IHC is improved with mAb 1813 because mAb EPR6893 was often limited by equivocal interpretations. We show that MTAP IHC and molecular assays are complementary in detecting 9p21 homozygous deletion. MTAP IHC may be particularly useful for low tumor purity samples and in low-resource settings.


Assuntos
Mesotelioma Maligno , Mesotelioma , Neoplasias Pleurais , Humanos , Biomarcadores Tumorais/análise , Inibidor p16 de Quinase Dependente de Ciclina/genética , Sequenciamento de Nucleotídeos em Larga Escala , Homozigoto , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Mesotelioma/diagnóstico , Mesotelioma/genética , Mesotelioma/patologia , Mesotelioma Maligno/genética , Neoplasias Pleurais/diagnóstico , Neoplasias Pleurais/genética , Neoplasias Pleurais/patologia , Deleção de Sequência , Ubiquitina Tiolesterase/genética
14.
J Neurooncol ; 167(1): 189-198, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38265748

RESUMO

INTRODUCTION: CDKN2A/B homozygous deletion is one of the defining features of grade 4 in IDH-mutant astrocytic tumours. AIM: To evaluate CDKN2A/B-deletion in IDH-mutant astrocytic tumours and its clinicopathological impact. MATERIALS AND METHODS: CDKN2A/B-deletion was evaluated by Fluorescence in-situ hybridisation (FISH) and interpreted by two recently accepted methods. RESULTS: Eighty-three out of 94 cases (histologically-grade 2: 3, grade 3: 46, grade 4: 34) were interpretable on FISH. Concordant CDKN2A/B-deletion was observed in 71% (27/38) of lower-grade tumours (n = 49) and 90% (27/30) of histological grade 4 tumours (n = 34). Both the interpretation methods showed good agreement (Kappa = 0.75). CDKN2A/B-deletion showed an inverse correlation for < 10% MIB-1 labeling index (p = 0.01) while that by method-2 showed a significant correlation for grade 4 (p = 0.02). No significant correlation was observed for any other clinicopathological parameters. Twenty-four patients showed progression/recurrence (including deaths), and no significant difference in frequency of CDKN2A/B deletion was observed among cases with disease progression across different histological grades. CONCLUSIONS: CDKN2A/B-deletion was observed across all the histological grades of IDH-mutant astrocytic tumours, expectedly more in the higher grade. FISH, as a method, can be used for the detection of CDKN2A/B homozygous deletion, when there is concordant interpretation.


Assuntos
Astrocitoma , Neoplasias Encefálicas , Humanos , Astrocitoma/genética , Astrocitoma/patologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Inibidor p16 de Quinase Dependente de Ciclina/genética , Fluorescência , Homozigoto , Isocitrato Desidrogenase/genética , Mutação , Deleção de Sequência , Inibidor de Quinase Dependente de Ciclina p15/genética
15.
Acta Neuropathol ; 147(1): 11, 2024 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-38183430

RESUMO

Prognostic factors and standards of care for astrocytoma, isocitrate dehydrogenase (IDH)-mutant, CNS WHO grade 4, remain poorly defined. Here we sought to explore disease characteristics, prognostic markers, and outcome in patients with this newly defined tumor type. We determined molecular biomarkers and assembled clinical and outcome data in patients with IDH-mutant astrocytomas confirmed by central pathology review. Patients were identified in the German Glioma Network cohort study; additional cohorts of patients with CNS WHO grade 4 tumors were identified retrospectively at two sites. In total, 258 patients with IDH-mutant astrocytomas (114 CNS WHO grade 2, 73 CNS WHO grade 3, 71 CNS WHO grade 4) were studied. The median age at diagnosis was similar for all grades. Karnofsky performance status at diagnosis inversely correlated with CNS WHO grade (p < 0.001). Despite more intensive treatment upfront with higher grade, CNS WHO grade was strongly prognostic: median overall survival was not reached for grade 2 (median follow-up 10.4 years), 8.1 years (95% CI 5.4-10.8) for grade 3, and 4.7 years (95% CI 3.4-6.0) for grade 4. Among patients with CNS WHO grade 4 astrocytoma, median overall survival was 5.5 years (95% CI 4.3-6.7) without (n = 58) versus 1.8 years (95% CI 0-4.1) with (n = 12) homozygous CDKN2A deletion. Lower levels of global DNA methylation as detected by LINE-1 methylation analysis were strongly associated with CNS WHO grade 4 (p < 0.001) and poor outcome. MGMT promoter methylation status was not prognostic for overall survival. Histomolecular stratification based on CNS WHO grade, LINE-1 methylation level, and CDKN2A status revealed four subgroups of patients with significantly different outcomes. In conclusion, CNS WHO grade, global DNA methylation status, and CDKN2A homozygous deletion are prognostic in patients with IDH-mutant astrocytoma. Combination of these parameters allows for improved prediction of outcome. These data aid in designing upcoming trials using IDH inhibitors.


Assuntos
Astrocitoma , Isocitrato Desidrogenase , Humanos , Astrocitoma/genética , Astrocitoma/terapia , Estudos de Coortes , Homozigoto , Isocitrato Desidrogenase/genética , Prognóstico , Estudos Retrospectivos , Deleção de Sequência
16.
mSphere ; 9(2): e0070323, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38251906

RESUMO

Promoter shutoff of essential genes in the diploid Candida albicans has often been insufficient to create tight, conditional null alleles due to leaky expression and has been a stumbling block in pathogenesis research. Moreover, homozygous deletion of non-essential genes has often been problematic due to the frequent aneuploidy in the mutant strains. Rapid, conditional depletion of essential genes by the anchor-away strategy has been successfully employed in Saccharomyces cerevisiae and other model organisms. Here, rapamycin mediates the dimerization of human FK506-binding protein (FKBP12) and FKBP12-rapamycin-binding (FRB) domain-containing target protein, resulting in relocalization to altered sub-cellular locations. In this work, we used the ribosomal protein Rpl13 as the anchor and took two nuclear proteins as targets to construct a set of mutants in a proof-of-principle approach. We first constructed a rapamycin-resistant C. albicans strain by introducing a dominant mutation in the CaTOR1 gene and a homozygous deletion of RBP1, the ortholog of FKBP12, a primary target of rapamycin. The FKBP12 and the FRB coding sequences were then CUG codon-adapted for C. albicans by site-directed mutagenesis. Anchor-away strains expressing the essential TBP1 gene or the non-essential SPT8 gene as FRB fusions were constructed. We found that rapamycin caused rapid cessation of growth of the TBP-AA strain within 15 minutes and the SPT8-AA strain phenocopied the constitutive filamentous phenotype of the spt8Δ/spt8Δ mutant. Thus, the anchor-away toolbox for C. albicans developed here can be employed for genome-wide analysis to identify gene function in a rapid and reliable manner, further accelerating anti-fungal drug development in C. albicans. IMPORTANCE: Molecular genetic studies thus far have identified ~27% open-reading frames as being essential for the vegetative growth of Candida albicans in rich medium out of a total 6,198 haploid set of open reading frames. However, a major limitation has been to construct rapid conditional alleles of essential C. albicans genes with near quantitative depletion of encoded proteins. Here, we have developed a toolbox for rapid and conditional depletion of genes that would aid studies of gene function of both essential and non-essential genes.


Assuntos
Candida albicans , Proteína 1A de Ligação a Tacrolimo , Humanos , Candida albicans/genética , Proteína 1A de Ligação a Tacrolimo/genética , Homozigoto , Deleção de Sequência , Sirolimo , Saccharomyces cerevisiae/genética , Códon
17.
Diagn Cytopathol ; 52(4): 211-216, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38243885

RESUMO

BACKGROUND: Mesothelioma is a malignant neoplasm with a poor survival rate. We aimed to investigate the importance of BAP1, MTAP (IHC), and p16/CDKN2A homozygous deletion (FISH) in cytologic material obtained from pleural effusion sampling, which is a less invasive procedure in the diagnosis of mesothelioma. METHODS: Our study discussed pleural cytology samples of cases with histopathologically proven mesothelioma diagnoses between 2017 and 2022. As the control group, materials that had pleural effusion sampling for other reasons and reactive mesothelial hyperplasia were included in the study. Cell blocks prepared from these materials were subjected to fluorescent in situ hybridization for p16/CDKN2A homozygous deletion and immunohistochemistry for BAP1 and MTAP. RESULTS: The specificity of the P16/CDKN2A homozygous deletion in diagnosing mesothelioma is 100%. Its sensitivity is 68.75%. The specificity of BAP1 immunohistochemical nuclear expression loss is 95%, while the sensitivity is 60%. Loss of nuclear expression of MTAP alone has the lowest specificity and sensitivity, with a specificity of 86% and a sensitivity of 43%. The highest sensitivity is reached when BAP1 loss and p16/CDKN2A homozygous deletion are evaluated together, increasing to 81%. The specificity is 95%. CONCLUSION: It has been determined that any marker alone cannot be used for a definitive mesothelioma diagnosis in pleural effusion cytological specimens; however, sensitivity increases in some combinations. The combination of BAP1 immunohistochemistry and p16/CDKN2A homozygous deletion detected by FISH, which has a higher specificity and sensitivity, can be routinely used in the diagnosis of mesothelioma under the guidance of clinical and radiologic information.


Assuntos
Mesotelioma Maligno , Mesotelioma , Neoplasias Mesoteliais , Derrame Pleural , Humanos , Citologia , Homozigoto , Hibridização in Situ Fluorescente , Deleção de Sequência , Mesotelioma/diagnóstico , Mesotelioma/genética , Mesotelioma Maligno/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Proteínas Supressoras de Tumor/genética , Ubiquitina Tiolesterase/genética
18.
J Neuropathol Exp Neurol ; 83(2): 125-130, 2024 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-38175671

RESUMO

Isocitrate dehydrogenase (IDH)-mutant astrocytoma with microvascular proliferation, necrosis, CDKN2A/B homozygous deletion, or any combination of these features corresponds to World Health Organization grade 4 according to current criteria. However, the prognostic significance of CDKN2A hemizygous deletion in IDH-mutant astrocytoma is not well established. We undertook a comprehensive study that included assessments of histological and genetic approaches to prognosis for these tumors. Samples from a cohort of 114 patients with extended observation were subjected to histological review and molecular analysis. CDKN2A (9p21) deletion was detected by fluorescence in situ hybridization. Overall survival (OS) was calculated via Kaplan-Meier estimation using the log-rank test. Histological grade, Ki-67 index, and the extent of surgical resection correlated with the OS of IDH-mutant astrocytoma patients. Both CDKN2A homozygous deletion and hemizygous deletion were detectable. Patients with CDKN2A homozygous-deletion tumors had the poorest OS; those with CDKN2A hemizygous-deletion tumors had an intermediate OS (p < .001). We then established a novel grading system that combined CDKN2A homozygous and hemizygous deletions with histological grade; the combined grading system was an independent prognostic factor for IDH-mutant astrocytomas. We conclude that CDKN2A homozygous and hemizygous deletion should be combined in a grading system for IDH-mutant astrocytomas.


Assuntos
Astrocitoma , Neoplasias Encefálicas , Humanos , Isocitrato Desidrogenase/genética , Homozigoto , Hibridização in Situ Fluorescente , Neoplasias Encefálicas/patologia , Mutação/genética , Deleção de Sequência , Astrocitoma/patologia , Prognóstico , Inibidor p16 de Quinase Dependente de Ciclina/genética
19.
Pediatr Rheumatol Online J ; 22(1): 12, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38183052

RESUMO

Haploinsufficiency of A20 (HA20) is a rare monogenic disease caused by heterozygous loss-of-function mutations in the tumor necrosis factor alpha-induced protein 3 (TNFAIP3) gene located on chromosome 6q23.3. The majority of disease-causing mutations in most cases of HA20 comprise single nucleotide variations, small insertions, or deletions in TNFAIP3, which result in a premature termination codon and subsequent disruption of its anti-inflammatory role. Large deletions have been reported sporadically. HA20 patients may present with a variety of autoinflammatory and autoimmune features during early childhood; however, cases with neonatal onset are rare. Here, we describe a Chinese neonate presenting with concomitant inflammatory and other syndromic manifestations caused by a 5.15 Mb interstitial deletion in chromosome 6; these deletions affect TNFAIP3. Taken together, the data extend the clinical and genetic spectra of HA20.


Assuntos
Cromossomos Humanos Par 6 , Haploinsuficiência , Deleção de Sequência , Humanos , Recém-Nascido , Povo Asiático , Haploinsuficiência/genética , Mutação , Doenças Raras , Cromossomos Humanos Par 6/genética
20.
Clin Exp Dermatol ; 49(3): 226-234, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-37815217

RESUMO

BACKGROUND: Dedicator of cytokinesis protein 8 (DOCK8) deficiency is an autosomal recessive form of combined immunodeficiency. This rare disorder is characterized by an increased predisposition to allergy, autoimmunity and malignancies. OBJECTIVES: To analyse clinical, immunological and molecular profiles of patients with DOCK8 deficiency. METHODS: Clinic records of all patients attending the primary immunodeficiency clinic from 2018 to 2021 were reviewed. Six patients from five families were found to have DOCK8 deficiency. RESULTS: Median age at diagnosis was 7.5 years (range 2-13), with a male/female ratio of 5 : 1. Among the six patients, recurrent eczematous skin lesions were the predominant cutaneous manifestation, present in five patients (83%). Warts and molluscum contagiosum were evident in two patients (33%) and one patient (16%), respectively. Two patients had recalcitrant prurigo nodularis lesions and two had epidermodysplasia verruciformis-like lesions. Food allergies and asthma were reported by one patient each. Of the six patients, recurrent sinopulmonary infections were detected in five (83%). Epstein-Barr virus-driven non-Hodgkin lymphoma with liver metastases was the only case of malignancy, in a 4-year-old boy. IgE was elevated in all patients. Lymphopenia and eosinophilia were observed in three patients (50%) and five patients (83.3%), respectively. Genetic analysis showed DOCK8 pathogenic variants in all patients: homozygous deletion mutations in two patients, compound heterozygous deletion mutations in one, and homozygous nonsense mutations in two. A novel pathogenic homozygous missense variant in the DOCK8 gene was identified in one patient. CONCLUSIONS: DOCK8 deficiency should be considered as a possibility in any patient with early onset eczema, cutaneous viral infections and increased predisposition to allergy, autoimmunity and malignancy.


Assuntos
Eczema , Infecções por Vírus Epstein-Barr , Hipersensibilidade , Síndrome de Job , Neoplasias , Humanos , Masculino , Feminino , Pré-Escolar , Criança , Adolescente , Síndrome de Job/genética , Citocinese , Centros de Atenção Terciária , Homozigoto , Deleção de Sequência , Herpesvirus Humano 4 , Eczema/genética , Fatores de Troca do Nucleotídeo Guanina/genética
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