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1.
Cancer Gene Ther ; 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622340

RESUMO

Novel therapeutic strategies are urgently required for osteosarcoma, given the early age at onset and persistently high mortality rate. Modern transcriptomics techniques can identify differentially expressed genes (DEGs) that may serve as biomarkers and therapeutic targets, so we screened for DEGs in osteosarcoma. We found that osteosarcoma cases could be divided into fair and poor survival groups based on gene expression profiles. Among the genes upregulated in the poor survival group, siRNA-mediated knockdown of the glycosylation-related gene C1GALT1 suppressed osteosarcoma cell proliferation in culture. Gene expression, phosphorylation, and glycome array analyses also demonstrated that C1GALT1 is required to maintain ERK signaling and cell cycle progression. Moreover, the C1GALT1 inhibitor itraconazole suppressed osteosarcoma cell proliferation in culture, while doxycycline-induced shRNA-mediated knockdown reduced xenograft osteosarcoma growth in mice. Elevated C1GALT1 expression is a potential early predictor of poor prognosis, while pharmacological inhibition may be a feasible treatment strategy for osteosarcoma.

2.
Hum Genet ; 143(3): 437-453, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38520561

RESUMO

General transcription factor IIIC subunit 5 (GTF3C5) encodes transcription factor IIIC63 (TFIIIC63). It binds to DNA to recruit another transcription factor, TFIIIB, and RNA polymerase III (Pol III) to mediate the transcription of small noncoding RNAs, such as tRNAs. Here, we report four individuals from three families presenting with a multisystem developmental disorder phenotype with biallelic variants in GTF3C5. The overlapping features include growth retardation, developmental delay, intellectual disability, dental anomalies, cerebellar malformations, delayed bone age, skeletal anomalies, and facial dysmorphism. Using lymphoblastoid cell lines (LCLs) from two affected individuals, we observed a reduction in TFIIIC63 protein levels compared to control LCLs. Genome binding of TFIIIC63 protein is also reduced in LCL from one of the affected individuals. Additionally, approximately 40% of Pol III binding regions exhibited reduction in the level of Pol III occupancy in the mutant genome relative to the control, while approximately 54% of target regions showed comparable levels of Pol III occupancy between the two, indicating partial impairment of Pol III occupancy in the mutant genome. Yeasts with subject-specific variants showed temperature sensitivity and impaired growth, supporting the notion that the identified variants have deleterious effects. gtf3c5 mutant zebrafish showed developmental defects, including a smaller body, head, and eyes. Taken together, our data show that GTF3C5 plays an important role in embryonic development, and that biallelic variants in this gene cause a multisystem developmental disorder. Our study adds GTF3C5-related disorder to the growing list of genetic disorders associated with Pol III transcription machinery.


Assuntos
Deficiências do Desenvolvimento , RNA Polimerase III , Fatores de Transcrição TFIII , Animais , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Alelos , Deficiências do Desenvolvimento/genética , Deficiências do Desenvolvimento/patologia , Deficiência Intelectual/genética , Mutação , Linhagem , Fenótipo , RNA Polimerase III/genética , RNA Polimerase III/metabolismo , Fatores de Transcrição TFII/genética , Fatores de Transcrição TFII/metabolismo , Fatores de Transcrição TFIII/genética , Fatores de Transcrição TFIII/metabolismo , Transcrição Gênica , Peixe-Zebra/genética
3.
HGG Adv ; 5(2): 100273, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38297832

RESUMO

Heterozygous missense variants and in-frame indels in SMC3 are a cause of Cornelia de Lange syndrome (CdLS), marked by intellectual disability, growth deficiency, and dysmorphism, via an apparent dominant-negative mechanism. However, the spectrum of manifestations associated with SMC3 loss-of-function variants has not been reported, leading to hypotheses of alternative phenotypes or even developmental lethality. We used matchmaking servers, patient registries, and other resources to identify individuals with heterozygous, predicted loss-of-function (pLoF) variants in SMC3, and analyzed population databases to characterize mutational intolerance in this gene. Here, we show that SMC3 behaves as an archetypal haploinsufficient gene: it is highly constrained against pLoF variants, strongly depleted for missense variants, and pLoF variants are associated with a range of developmental phenotypes. Among 14 individuals with SMC3 pLoF variants, phenotypes were variable but coalesced on low growth parameters, developmental delay/intellectual disability, and dysmorphism, reminiscent of atypical CdLS. Comparisons to individuals with SMC3 missense/in-frame indel variants demonstrated an overall milder presentation in pLoF carriers. Furthermore, several individuals harboring pLoF variants in SMC3 were nonpenetrant for growth, developmental, and/or dysmorphic features, and some had alternative symptomatologies with rational biological links to SMC3. Analyses of tumor and model system transcriptomic data and epigenetic data in a subset of cases suggest that SMC3 pLoF variants reduce SMC3 expression but do not strongly support clustering with functional genomic signatures of typical CdLS. Our finding of substantial population-scale LoF intolerance in concert with variable growth and developmental features in subjects with SMC3 pLoF variants expands the scope of cohesinopathies, informs on their allelic architecture, and suggests the existence of additional clearly LoF-constrained genes whose disease links will be confirmed only by multilayered genomic data paired with careful phenotyping.


Assuntos
Síndrome de Cornélia de Lange , Deficiência Intelectual , Humanos , Proteínas de Ciclo Celular/genética , Proteoglicanas de Sulfatos de Condroitina/genética , Proteínas Cromossômicas não Histona/genética , Síndrome de Cornélia de Lange/genética , Heterozigoto , Deficiência Intelectual/genética , Mutação , Fenótipo
4.
Sci Adv ; 9(50): eadj4407, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38091391

RESUMO

Myeloid/natural killer (NK) cell precursor acute leukemia (MNKPL) has been described on the basis of its unique immunophenotype and clinical phenotype. However, there is no consensus on the characteristics for identifying this disease type because of its rarity and lack of defined distinctive molecular characteristics. In this study, multiomics analysis revealed that MNKPL is distinct from acute myeloid leukemia, T cell acute lymphoblastic leukemia, and mixed-phenotype acute leukemia (MPAL), and NOTCH1 and RUNX3 activation and BCL11B down-regulation are hallmarks of MNKPL. Although NK cells have been classically considered to be lymphoid lineage-derived, the results of our single-cell analysis using MNKPL cells suggest that NK cells and myeloid cells share common progenitor cells. Treatment outcomes for MNKPL are unsatisfactory, even when hematopoietic cell transplantation is performed. Multiomics analysis and in vitro drug sensitivity assays revealed increased sensitivity to l-asparaginase and reduced levels of asparagine synthetase (ASNS), supporting the clinically observed effectiveness of l-asparaginase.


Assuntos
Asparaginase , Leucemia Mieloide Aguda , Humanos , Leucemia Mieloide Aguda/terapia , Doença Aguda , Células Matadoras Naturais , Resultado do Tratamento , Proteínas Repressoras , Proteínas Supressoras de Tumor
5.
medRxiv ; 2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37808847

RESUMO

Heterozygous missense variants and in-frame indels in SMC3 are a cause of Cornelia de Lange syndrome (CdLS), marked by intellectual disability, growth deficiency, and dysmorphism, via an apparent dominant-negative mechanism. However, the spectrum of manifestations associated with SMC3 loss-of-function variants has not been reported, leading to hypotheses of alternative phenotypes or even developmental lethality. We used matchmaking servers, patient registries, and other resources to identify individuals with heterozygous, predicted loss-of-function (pLoF) variants in SMC3, and analyzed population databases to characterize mutational intolerance in this gene. Here, we show that SMC3 behaves as an archetypal haploinsufficient gene: it is highly constrained against pLoF variants, strongly depleted for missense variants, and pLoF variants are associated with a range of developmental phenotypes. Among 13 individuals with SMC3 pLoF variants, phenotypes were variable but coalesced on low growth parameters, developmental delay/intellectual disability, and dysmorphism reminiscent of atypical CdLS. Comparisons to individuals with SMC3 missense/in-frame indel variants demonstrated a milder presentation in pLoF carriers. Furthermore, several individuals harboring pLoF variants in SMC3 were nonpenetrant for growth, developmental, and/or dysmorphic features, some instead having intriguing symptomatologies with rational biological links to SMC3 including bone marrow failure, acute myeloid leukemia, and Coats retinal vasculopathy. Analyses of transcriptomic and epigenetic data suggest that SMC3 pLoF variants reduce SMC3 expression but do not result in a blood DNA methylation signature clustering with that of CdLS, and that the global transcriptional signature of SMC3 loss is model-dependent. Our finding of substantial population-scale LoF intolerance in concert with variable penetrance in subjects with SMC3 pLoF variants expands the scope of cohesinopathies, informs on their allelic architecture, and suggests the existence of additional clearly LoF-constrained genes whose disease links will be confirmed only by multi-layered genomic data paired with careful phenotyping.

6.
Mol Ther ; 31(12): 3424-3440, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37705244

RESUMO

Stem cell gene therapy using the MFGS-gp91phox retroviral vector was performed on a 27-year-old patient with X-linked chronic granulomatous disease (X-CGD) in 2014. The patient's refractory infections were resolved, whereas the oxidase-positive neutrophils disappeared within 6 months. Thirty-two months after gene therapy, the patient developed myelodysplastic syndrome (MDS), and vector integration into the MECOM locus was identified in blast cells. The vector integration into MECOM was detectable in most myeloid cells at 12 months after gene therapy. However, the patient exhibited normal hematopoiesis until the onset of MDS, suggesting that MECOM transactivation contributed to clonal hematopoiesis, and the blast transformation likely arose after the acquisition of additional genetic lesions. In whole-genome sequencing, the biallelic loss of the WT1 tumor suppressor gene, which occurred immediately before tumorigenesis, was identified as a potential candidate genetic alteration. The provirus CYBB cDNA in the blasts contained 108 G-to-A mutations exclusively in the coding strand, suggesting the occurrence of APOBEC3-mediated hypermutations during the transduction of CD34-positive cells. A hypermutation-mediated loss of oxidase activity may have facilitated the survival and proliferation of the clone with MECOM transactivation. Our data provide valuable insights into the complex mechanisms underlying the development of leukemia in X-CGD gene therapy.


Assuntos
Doença Granulomatosa Crônica , Síndromes Mielodisplásicas , Humanos , Adulto , Doença Granulomatosa Crônica/genética , Doença Granulomatosa Crônica/terapia , NADPH Oxidases/genética , Hematopoiese Clonal , Terapia Genética , Retroviridae/genética , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/terapia , NADPH Oxidase 2/genética
7.
Cancer Med ; 12(10): 11264-11273, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37021926

RESUMO

BACKGROUND: Second malignant neoplasms (SMNs) are one of the most severe late complications after pediatric cancer treatment. However, the effect of genetic variation on SMNs remains unclear. In this study, we revealed germline genetic factors that contribute to the development of SMNs after treatment of pediatric solid tumors. METHODS: We performed whole-exome sequencing in 14 pediatric patients with SMNs, including three brain tumors. RESULTS: Our analysis revealed that five of 14 (35.7%) patients had pathogenic germline variants in cancer-predisposing genes (CPGs), which was significantly higher than in the control cohort (p < 0.01). The identified genes with variants were TP53 (n = 2), DICER1 (n = 1), PMS2 (n = 1), and PTCH1 (n = 1). In terms of the type of subsequent cancer, leukemia and multiple episodes of SMN had an exceptionally high rate of CPG pathogenic variants. None of the patients with germline variants had a family history of SMN development. Mutational signature analysis showed that platinum drugs contributed to the development of SMN in three cases, which suggests the role of platinum agents in SMN development. CONCLUSIONS: We highlight that overlapping effects of genetic background and primary cancer treatment contribute to the development of second cancers after treatment of pediatric solid tumors. A comprehensive analysis of germline and tumor samples may be useful to predict the risk of secondary cancers.


Assuntos
Neoplasias Encefálicas , Leucemia , Segunda Neoplasia Primária , Criança , Humanos , Segunda Neoplasia Primária/epidemiologia , Segunda Neoplasia Primária/genética , Prevalência , Platina , Neoplasias Encefálicas/complicações , Mutação em Linhagem Germinativa , Predisposição Genética para Doença , Ribonuclease III/genética , RNA Helicases DEAD-box/genética
8.
Genet Med ; 25(7): 100861, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37087635

RESUMO

PURPOSE: This study aimed to establish variants in CBX1, encoding heterochromatin protein 1ß (HP1ß), as a cause of a novel syndromic neurodevelopmental disorder. METHODS: Patients with CBX1 variants were identified, and clinician researchers were connected using GeneMatcher and physician referrals. Clinical histories were collected from each patient. To investigate the pathogenicity of identified variants, we performed in vitro cellular assays and neurobehavioral and cytological analyses of neuronal cells obtained from newly generated Cbx1 mutant mouse lines. RESULTS: In 3 unrelated individuals with developmental delay, hypotonia, and autistic features, we identified heterozygous de novo variants in CBX1. The identified variants were in the chromodomain, the functional domain of HP1ß, which mediates interactions with chromatin. Cbx1 chromodomain mutant mice displayed increased latency-to-peak response, suggesting the possibility of synaptic delay or myelination deficits. Cytological and chromatin immunoprecipitation experiments confirmed the reduction of mutant HP1ß binding to heterochromatin, whereas HP1ß interactome analysis demonstrated that the majority of HP1ß-interacting proteins remained unchanged between the wild-type and mutant HP1ß. CONCLUSION: These collective findings confirm the role of CBX1 in developmental disabilities through the disruption of HP1ß chromatin binding during neurocognitive development. Because HP1ß forms homodimers and heterodimers, mutant HP1ß likely sequesters wild-type HP1ß and other HP1 proteins, exerting dominant-negative effects.


Assuntos
Homólogo 5 da Proteína Cromobox , Heterocromatina , Animais , Camundongos , Cromatina/genética , Proteínas Cromossômicas não Histona/genética , Histonas/genética , Histonas/metabolismo
9.
Cancer Cell Int ; 23(1): 36, 2023 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-36841758

RESUMO

BACKGROUND: Mixed lineage leukemia 1-rearranged (MLL1-r) acute leukemia patients respond poorly to currently available treatments and there is a need to develop more effective therapies directly disrupting the Menin‒MLL1 complex. Small-molecule-mediated inhibition of the protein‒protein interaction between Menin and MLL1 fusion proteins is a potential therapeutic strategy for patients with MLL1-r or mutated-nucleophosmin 1 (NPM1c) acute leukemia. In this study, we preclinically evaluated the new compound DS-1594a and its salts. METHODS: We evaluated the preclinical efficacy of DS-1594a as well as DS-1594a·HCl (the HCl salt of DS-1594a) and DS-1594a·succinate (the succinic acid salt of DS-1594a, DS-1594b) in vitro and in vivo using acute myeloid leukemia (AML)/acute lymphoblastic leukemia (ALL) models. RESULTS: Our results showed that MLL1-r or NPM1c human leukemic cell lines were selectively and highly sensitive to DS-1594a·HCl, with 50% growth inhibition values < 30 nM. Compared with cytrabine, the standard chemotherapy drug as AML therapy, both DS-1594a·HCl and DS-1594a·succinate mediated the eradication of potential leukemia-initiating cells by enhancing differentiation and reducing serial colony-forming potential in MLL1-r AML cells in vitro. The results were confirmed by flow cytometry, RNA sequencing, RT‒qPCR and chromatin immunoprecipitation sequencing analyses. DS-1594a·HCl and DS-1594a·succinate exhibited significant antitumor efficacy and survival benefit in MOLM-13 cell and patient-derived xenograft models of MLL1-r or NPM1c acute leukemia in vivo. CONCLUSION: We have generated a novel, potent, orally available small-molecule inhibitor of the Menin-MLL1 interaction, DS-1594a. Our results suggest that DS-1594a has medicinal properties distinct from those of cytarabine and that DS-1594a has the potential to be a new anticancer therapy and support oral dosing regimen for clinical studies (NCT04752163).

11.
Cytogenet Genome Res ; 162(5): 237-243, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36516793

RESUMO

Brachydactyly mental retardation syndrome (BDMR) typically results from large deletions (>2-9 Mb) in distal 2q37. Haploinsufficiency of HDAC4 with incomplete penetrance has been proposed as the primary genetic cause of BDMR. To date, pure 2q37 deletions distal to HDAC4 were reported only in a limited number of individuals who share a subset of the clinical manifestations seen in cases with 2q37 deletions encompassing HDAC4. Here, we present a 4-year-old African American male who carries the smallest established 2q37.3 deletion distal to HDAC4 (827.1 kb; 16 OMIM genes). His clinical features that overlap with BDMR phenotypes include expressive-receptive language delay, behavioral issues, mild facial dysmorphism such as frontal bossing, and bilateral 5th finger brachydactyly and clinodactyly. The deletion was inherited from his mother with a history of learning difficulties and similar facial dysmorphism. This case provides important genotype-phenotype correlation information and suggests a 2q37 region distal to HDAC4 encompassing the HDLBP gene may contribute to a subset of clinical features overlapping with those seen in individuals with BDMR.


Assuntos
Braquidactilia , Deficiência Intelectual , Masculino , Humanos , Deficiência Intelectual/genética , Braquidactilia/genética , Deleção Cromossômica , Estudos de Associação Genética , Fenótipo , Cromossomos Humanos Par 2
12.
Oncogene ; 41(46): 4994-5007, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36319669

RESUMO

Neuroblastomas require novel therapies that are based on the exploitation of their biological mechanism. To address this need, we analyzed the DNA methylation and expression datasets of neuroblastomas, extracted a candidate gene characterizing the aggressive features, and conducted functional studies. Based on the DNA methylation data, we identified a subgroup of neuroblastoma cases with 11q loss of heterozygosity with extremely poor prognosis. PHGDH, a serine metabolism-related gene, was extracted as a candidate with strong expression and characteristic methylation in this subgroup as well as in cases with MYCN amplification. PHGDH inhibition suppressed neuroblastoma cell proliferation in vitro and in vivo, indicating that the inhibition of serine metabolism by PHGDH inhibitors is a therapeutic alternative for neuroblastoma. Inhibiting the arginine metabolism, which is closely related to serine metabolism using arginine deiminase, had a combination effect both in vitro and in vivo, especially on extracellular arginine-dependent neuroblastoma cells with ASS1 deficiency. Expression and metabolome analyses of post-dose cells confirmed the synergistic effects of treatments targeting serine and arginine indicated that xCT inhibitors that inhibit cystine uptake could be candidates for further combinatorial treatment. Our results highlight the rational therapeutic strategy of targeting serine/arginine metabolism for intractable neuroblastoma.


Assuntos
Metilação de DNA , Neuroblastoma , Humanos , Metilação de DNA/genética , Neuroblastoma/tratamento farmacológico , Neuroblastoma/genética , Neuroblastoma/metabolismo , Proliferação de Células/genética , Serina/metabolismo , Arginina/genética , Arginina/metabolismo , Proteína Proto-Oncogênica N-Myc/genética , Proteína Proto-Oncogênica N-Myc/metabolismo , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica
13.
Clin Case Rep ; 10(11): e6535, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36415709

RESUMO

Haploinsufficiency of FOXP2 causes FOXP2-related speech and language disorder. We report a 9.8 Mb deletion downstream of FOXP2 in a girl with speech and language impairment, developmental delay, and other features. We propose involvement of FOXP2 in pathogenesis of these phenotypes, likely due to positional effects on the gene.

14.
Nat Commun ; 13(1): 4501, 2022 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-36042201

RESUMO

KMT2A-rearranged infant acute lymphoblastic leukemia (ALL) represents the most refractory type of childhood leukemia. To uncover the molecular heterogeneity of this disease, we perform RNA sequencing, methylation array analysis, whole exome and targeted deep sequencing on 84 infants with KMT2A-rearranged leukemia. Our multi-omics clustering followed by single-sample and single-cell inference of hematopoietic differentiation establishes five robust integrative clusters (ICs) with different master transcription factors, fusion partners and corresponding stages of B-lymphopoietic and early hemato-endothelial development: IRX-type differentiated (IC1), IRX-type undifferentiated (IC2), HOXA-type MLLT1 (IC3), HOXA-type MLLT3 (IC4), and HOXA-type AFF1 (IC5). Importantly, our deep mutational analysis reveals that the number of RAS pathway mutations predicts prognosis and that the most refractory subgroup of IC2 possesses 100% frequency and the heaviest burden of RAS pathway mutations. Our findings highlight the previously under-appreciated intra- and inter-patient heterogeneity of KMT2A-rearranged infant ALL and provide a rationale for the future development of genomics-guided risk stratification and individualized therapy.


Assuntos
Histona-Lisina N-Metiltransferase/genética , Proteína de Leucina Linfoide-Mieloide/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras , Fusão Gênica , Humanos , Lactente , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Fatores de Transcrição/genética
15.
Genes Chromosomes Cancer ; 61(11): 662-669, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35655408

RESUMO

Liquid biopsy, a method of detecting genomic alterations using blood specimens, has recently attracted attention as a noninvasive alternative to surgical tissue biopsy. We attempted quantitative analysis to detect amplification of MYCN (MYCNamp) and loss of heterozygosity at 11q (11qLOH), which are clinical requisites as prognostic factors of neuroblastoma (NB). In this study, cell-free DNA (cfDNA) was extracted from plasma samples from 24 NB patients at diagnosis. Copy numbers of MYCN and NAGK genes were quantitatively analyzed by droplet digital PCR (ddPCR). 11qLOH was also assessed by detecting allelic imbalances of heterozygous single nucleotide polymorphisms in the 11q region. The results obtained were compared to those of specimens from tumor tissues. The correlation coefficient of MYCN copy number of cfDNA and tumor DNA was 0.88 (p < 0.00001). 11qLOH was also accurately detected from cfDNA, except for one case with localized NB. Given the high accuracy of liquid biopsy, to investigate components of cfDNA, the proportion of tumor-derived DNA was estimated by examining the variant allele frequency of tumor-specific mutations in cfDNA. The proportion of tumor-derived DNA in cfDNA was 42.5% (range, 16.9%-55.9%), suggesting sufficient sensitivity of liquid biopsy for NB. In conclusion, MYCN copy number and 11qLOH could be quantitatively analyzed in plasma cfDNA by ddPCR assay. These results suggest that plasma cfDNA can be substituted for tumor DNA and can also be applied for comprehensive genomic profiling analysis.


Assuntos
Ácidos Nucleicos Livres , Neuroblastoma , Ácidos Nucleicos Livres/genética , Variações do Número de Cópias de DNA , DNA de Neoplasias , Humanos , Biópsia Líquida , Proteína Proto-Oncogênica N-Myc/genética , Neuroblastoma/diagnóstico , Neuroblastoma/genética , Neuroblastoma/patologia
16.
Nat Cell Biol ; 24(5): 748-756, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35534577

RESUMO

Centromeres are defined epigenetically by the histone H3 variant CENP-A. The propagation cycle by which pre-existing CENP-A nucleosomes serve as templates for nascent assembly predicts the epigenetic memory of weakened centromeres. Using a mouse model with reduced levels of CENP-A nucleosomes, we find that an embryonic plastic phase precedes epigenetic memory through development. During this phase, nascent CENP-A nucleosome assembly depends on the maternal Cenpa genotype rather than the pre-existing template. Weakened centromeres are thus limited to a single generation, and parental epigenetic differences are eliminated by equal assembly on maternal and paternal centromeres. These differences persist, however, when the underlying DNA of parental centromeres differs in repeat abundance, as assembly during the plastic phase also depends on sufficient repetitive centromere DNA. With contributions of centromere DNA and the Cenpa maternal effect, we propose that centromere inheritance naturally minimizes fitness costs associated with weakened centromeres or epigenetic differences between parents.


Assuntos
Herança Materna , Nucleossomos , Autoantígenos/genética , Proteínas de Ciclo Celular/genética , Centrômero/genética , Centrômero/metabolismo , Proteína Centromérica A/genética , Proteínas Cromossômicas não Histona/genética , Proteínas Cromossômicas não Histona/metabolismo , Epigênese Genética , Histonas/genética , Histonas/metabolismo , Herança Materna/genética , Nucleossomos/genética , Plásticos
18.
Oncogene ; 41(20): 2789-2797, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35411036

RESUMO

The identification of molecular events underlying the pathogenesis of neuroblastoma can likely result in improved clinical outcomes for this disease. In this study, a translocation within chromosome 2p and 4q was found to bring about the formation of an in-frame fusion gene that was composed of portions of the teneurin transmembrane protein 3 (TENM3, also known as ODZ3) gene and the anaplastic lymphoma kinase (ALK) gene in tumor cells from patients with neuroblastoma. Expression of the full length TENM3-ALK cDNA in NIH-3T3 cells led to the formation of a fusion protein that: (1) possesses constitutive tyrosine kinase activity, (2) induces strong activation of the downstream targets of extracellular signal-regulated kinase (ERK), protein kinase B (a.k.a. AKT), and signal transducer and activator of transcription 3 (STAT3), (3) provokes oncogenic transformation in NOD.Cg-PrkdcscidIl2rgtm1Sug/ShiJic mice, and (4) possesses sensitivity to ALK inhibitors in vitro and in vivo. Our findings demonstrated that patients with neuroblastoma may express a transforming fusion kinase, which is a promising candidate for a therapeutic target and a diagnostic molecular marker for neuroblastoma. The in-frame 5' partner gene that fuses with ALK has not been reported previously in neuroblastoma. Our data provide novel biological insights into the mechanism of ALK activation due to translocation, with implications for neuroblastoma tumorigenesis, and could be useful as a vital marker for the accurate diagnosis of this type of neuroblastoma.


Assuntos
Quinase do Linfoma Anaplásico , Neuroblastoma , Proteínas de Fusão Oncogênica , Receptores Proteína Tirosina Quinases , Quinase do Linfoma Anaplásico/genética , Animais , Linhagem Celular Tumoral , Proliferação de Células , Transformação Celular Neoplásica/genética , Humanos , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos NOD , Células NIH 3T3 , Proteínas do Tecido Nervoso/genética , Neuroblastoma/patologia , Proteínas de Fusão Oncogênica/genética , Receptores Proteína Tirosina Quinases/metabolismo , Translocação Genética/genética
19.
Cancer Rep (Hoboken) ; 5(9): e1559, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-34553842

RESUMO

BACKGROUND: Lymphoblastic lymphoma (LBL) and acute lymphoblastic leukemia (ALL) are categorized as the same entity under precursor lymphoid neoplasms in the World Health Organization classification. However, compared to B-cell ALL, the molecular genetic makeup of B-cell LBL remains to be understood, mainly due to its rarity. We performed whole exome sequencing (WES) on seven patients with TCF3-PBX1-positive B-cell LBL. METHODS: WES was performed using DNA extracted from tumor specimens and paired blood samples at remission for six patients, and tumor-only analysis was performed for one patient whose remission sample was not available. For one patient, a relapsed sample was also analyzed. RESULTS: KMT2D variants and 6q LOH were found as recurrent alterations. Somatic variants of KMT2D were identified in three of the seven patients. Of note, the two patients with heterozygous nonsense variant of KMT2D were at stage III, without bone marrow infiltration. 6q LOH was also identified in two others, out of the seven patients. The common 6q deleted region of the two patients ranged from 6q12 to 6q16.3. Both patients had bone marrow infiltration. Analysis of recurrent case also revealed that the relapsed clone might be derived from a minor clone of the bone marrow at diagnosis. CONCLUSION: In this study, through WES for seven patients with TCF3-PBX1-positive B-LBL, we identified KMT2D mutations and 6q LOH as recurrent alterations. In order to elucidate the relationship between these recurrent alterations and disease specificity or outcomes, further studies comparing with TCF3-PBX1-positive B-ALL are required.


Assuntos
Proteínas de Fusão Oncogênica , Leucemia-Linfoma Linfoblástico de Células Precursoras , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Humanos , Proteínas de Fusão Oncogênica/genética , Fator de Transcrição 1 de Leucemia de Células Pré-B , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética
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