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R-2-hydroxyglutarate (R-2HG), produced at high levels by mutant isocitrate dehydrogenase 1/2 (IDH1/2) enzymes, was reported as an oncometabolite. We show here that R-2HG also exerts a broad anti-leukemic activity in vitro and in vivo by inhibiting leukemia cell proliferation/viability and by promoting cell-cycle arrest and apoptosis. Mechanistically, R-2HG inhibits fat mass and obesity-associated protein (FTO) activity, thereby increasing global N6-methyladenosine (m6A) RNA modification in R-2HG-sensitive leukemia cells, which in turn decreases the stability of MYC/CEBPA transcripts, leading to the suppression of relevant pathways. Ectopically expressed mutant IDH1 and S-2HG recapitulate the effects of R-2HG. High levels of FTO sensitize leukemic cells to R-2HG, whereas hyperactivation of MYC signaling confers resistance that can be reversed by the inhibition of MYC signaling. R-2HG also displays anti-tumor activity in glioma. Collectively, while R-2HG accumulated in IDH1/2 mutant cancers contributes to cancer initiation, our work demonstrates anti-tumor effects of 2HG in inhibiting proliferation/survival of FTO-high cancer cells via targeting FTO/m6A/MYC/CEBPA signaling.
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Antineoplásicos/farmacología , Neoplasias Encefálicas/tratamiento farmacológico , Glioma/tratamiento farmacológico , Glutaratos/farmacología , Leucemia/tratamiento farmacológico , Transducción de Señal/efectos de los fármacos , Adenosina/análogos & derivados , Adenosina/metabolismo , Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato/metabolismo , Animales , Antineoplásicos/uso terapéutico , Proteínas Potenciadoras de Unión a CCAAT/metabolismo , Línea Celular Tumoral , Glutaratos/uso terapéutico , Células HEK293 , Humanos , Células Jurkat , Ratones , Proteínas Proto-Oncogénicas c-myc/metabolismo , Procesamiento Postranscripcional del ARNRESUMEN
In cereal grains, starch is synthesized by the concerted actions of multiple enzymes on the surface of starch granules within the amyloplast. However, little is known about how starch-synthesizing enzymes access starch granules, especially for amylopectin biosynthesis. Here, we show that the rice (Oryza sativa) floury endosperm9 (flo9) mutant is defective in amylopectin biosynthesis, leading to grains exhibiting a floury endosperm with a hollow core. Molecular cloning revealed that FLO9 encodes a plant-specific protein homologous to Arabidopsis (Arabidopsis thaliana) LIKE EARLY STARVATION1 (LESV). Unlike Arabidopsis LESV, which is involved in starch metabolism in leaves, OsLESV is required for starch granule initiation in the endosperm. OsLESV can directly bind to starch by its C-terminal tryptophan (Trp)-rich region. Cellular and biochemical evidence suggests that OsLESV interacts with the starch-binding protein FLO6, and loss-of-function mutations of either gene impair ISOAMYLASE1 (ISA1) targeting to starch granules. Genetically, OsLESV acts synergistically with FLO6 to regulate starch biosynthesis and endosperm development. Together, our results identify OsLESV-FLO6 as a non-enzymatic molecular module responsible for ISA1 localization on starch granules, and present a target gene for use in biotechnology to control starch content and composition in rice endosperm.
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Endospermo , Regulación de la Expresión Génica de las Plantas , Oryza , Proteínas de Plantas , Almidón , Oryza/genética , Oryza/metabolismo , Oryza/crecimiento & desarrollo , Endospermo/metabolismo , Endospermo/genética , Almidón/metabolismo , Almidón/biosíntesis , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Amilopectina/metabolismo , Mutación , Plantas Modificadas GenéticamenteRESUMEN
Acute myeloid leukemia (AML) is an aging-related and heterogeneous hematopoietic malignancy. In this study, a total of 1,474 newly diagnosed AML patients with RNA sequencing data were enrolled, and targeted or whole exome sequencing data were obtained in 94% cases. The correlation of aging-related factors including age and clonal hematopoiesis (CH), gender, and genomic/transcriptomic profiles (gene fusions, genetic mutations, and gene expression networks or pathways) was systematically analyzed. Overall, AML patients aged 60 y and older showed an apparently dismal prognosis. Alongside age, the frequency of gene fusions defined in the World Health Organization classification decreased, while the positive rate of gene mutations, especially CH-related ones, increased. Additionally, the number of genetic mutations was higher in gene fusion-negative (GF-) patients than those with GF. Based on the status of CH- and myelodysplastic syndromes (MDS)-related mutations, three mutant subgroups were identified among the GF- AML cohort, namely, CH-AML, CH-MDS-AML, and other GF- AML. Notably, CH-MDS-AML demonstrated a predominance of elderly and male cases, cytopenia, and significantly adverse clinical outcomes. Besides, gene expression networks including HOXA/B, platelet factors, and inflammatory responses were most striking features associated with aging and poor prognosis in AML. Our work has thus unraveled the intricate regulatory circuitry of interactions among different age, gender, and molecular groups of AML.
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Leucemia Mieloide Aguda , Síndromes Mielodisplásicos , Anciano , Humanos , Masculino , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Envejecimiento/genética , Mutación , Síndromes Mielodisplásicos/genética , Síndromes Mielodisplásicos/patología , PronósticoRESUMEN
Identifying and protecting hotspots of endemism and species richness is crucial for mitigating the global biodiversity crisis. However, our understanding of spatial diversity patterns is far from complete, which severely limits our ability to conserve biodiversity hotspots. Here, we report a comprehensive analysis of amphibian species diversity in China, one of the most species-rich countries on Earth. Our study combines 20 y of field surveys with new molecular analyses of 521 described species and also identifies 100 potential cryptic species. We identify 10 hotspots of amphibian diversity in China, each with exceptional species richness and endemism and with exceptional phylogenetic diversity and phylogenetic endemism (based on a new time-calibrated, species-level phylogeny for Chinese amphibians). These 10 hotspots encompass 59.6% of China's described amphibian species, 49.0% of cryptic species, and 55.6% of species endemic to China. Only four of these 10 hotspots correspond to previously recognized biodiversity hotspots. The six new hotspots include the Nanling Mountains and other mountain ranges in South China. Among the 186 species in the six new hotspots, only 9.7% are well covered by protected areas and most (88.2%) are exposed to high human impacts. Five of the six new hotspots are under very high human pressure and are in urgent need of protection. We also find that patterns of richness in cryptic species are significantly related to those in described species but are not identical.
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Anfibios , Biodiversidad , Filogenia , Animales , Anfibios/clasificación , China , Conservación de los Recursos NaturalesRESUMEN
ABSTRACT: We report on the antileukemic activity of homoharringtonine (HHT) in T-cell acute lymphoblastic leukemia (T-ALL). We showed that HHT inhibited the NOTCH/MYC pathway and induced significantly longer survival in mouse and patient-derived T-ALL xenograft models, supporting HHT as a promising agent for T-ALL.
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Harringtoninas , Homoharringtonina , Leucemia-Linfoma Linfoblástico de Células T Precursoras , Proteínas Proto-Oncogénicas c-myc , Receptores Notch , Transducción de Señal , Ensayos Antitumor por Modelo de Xenoinjerto , Homoharringtonina/farmacología , Homoharringtonina/uso terapéutico , Animales , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamiento farmacológico , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patología , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Humanos , Ratones , Harringtoninas/farmacología , Harringtoninas/uso terapéutico , Receptores Notch/metabolismo , Receptores Notch/antagonistas & inhibidores , Transducción de Señal/efectos de los fármacos , Proteínas Proto-Oncogénicas c-myc/metabolismo , Proteínas Proto-Oncogénicas c-myc/genética , Ratones SCID , Ratones Endogámicos NODRESUMEN
In the phase 3 POLARIX study in previously untreated diffuse large B-cell lymphoma, polatuzumab vedotin combined with rituximab plus cyclophosphamide, doxorubicin, and prednisone (Pola-R-CHP) significantly improved progression-free survival (PFS) compared with rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) with similar safety. Patients were randomized 1:1 to 6 cycles of Pola-R-CHP or R-CHOP plus 2 cycles of rituximab alone. For registration of POLARIX in China, consistency of PFS in an Asia subpopulation (defined as ≥50% of the risk reduction in PFS expected in the global population) was evaluated. Overall, 281 patients were analyzed: 160 patients from Asia in the intention-to-treat (ITT) population of the global study and 121 from an ITT China extension cohort. Of these, 141 were randomized to Pola-R-CHP and 140 to R-CHOP. At data cutoff (28 June 2021; median follow-up 24.2 months), PFS met the consistency definition with the global population, and was superior with Pola-R-CHP vs R-CHOP (hazard ratio, 0.64; 95% confidence interval [CI], 0.40-1.03). Two-year PFS was 74.2% (95% CI, 65.7-82.7) and 66.5% (95% CI, 57.3-75.6) with Pola-R-CHP and R-CHOP, respectively. Safety was comparable between Pola-R-CHP and R-CHOP, including rates of grade 3 to 4 adverse events (AEs; 72.9% vs 66.2%, respectively), serious AEs (32.9% vs 32.4%), grade 5 AEs (1.4% vs 0.7%), AEs leading to study treatment discontinuation (5.0% vs 7.2%), and any-grade peripheral neuropathy (44.3% vs 50.4%). These findings demonstrate consistent efficacy and safety of Pola-R-CHP vs R-CHOP in the Asia and global populations in POLARIX. This trial was registered at https://clinicaltrials.gov/ct2/home as # NCT03274492.
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Protocolos de Quimioterapia Combinada Antineoplásica , Linfoma de Células B Grandes Difuso , Humanos , Rituximab/efectos adversos , Prednisona/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Ciclofosfamida/efectos adversos , Vincristina/efectos adversos , Doxorrubicina/efectos adversos , Linfoma de Células B Grandes Difuso/terapiaRESUMEN
USP25 encodes ubiquitin-specific protease 25, a key member of the deubiquitinating enzyme family that is involved in neural fate determination. Although abnormal expression in Down's syndrome was reported previously, the specific role of USP25 in human diseases has not been defined. In this study, we performed trio-based whole exome sequencing in a cohort of 319 cases (families) with generalized epilepsy of unknown aetiology. Five heterozygous USP25 variants, including two de novo and three co-segregated variants, were determined in eight individuals affected by generalized seizures and/or febrile seizures from five unrelated families. The frequency of USP25 variants showed a significantly high aggregation in this cohort compared with the East Asian population and all populations in the gnomAD database. The mean age at onset of febrile and afebrile seizures were 10 months (infancy) and 11.8 years (juvenile), respectively. The patients achieved seizure freedom, except that one had occasional nocturnal seizures at the last follow-up. Two patients exhibited intellectual disability. Usp25 was expressed ubiquitously in mouse brain with two peaks, on embryonic Days 14-16 and postnatal Day 21, respectively. In human brain, likewise, USP25 is expressed in the fetus/early childhood stage and with a second peak at â¼12-20 years old, consistent with the seizure onset age in patients during infancy and in juveniles. To investigate the functional impact of USP25 deficiency in vivo, we established Usp25 knockout mice, which showed increased seizure susceptibility compared with wild-type mice in a pentylenetetrazol-induced seizure test. To explore the impact of USP25 variants, we used multiple functional detections. In HEK293 T cells, the variant associated with a severe phenotype (p.Gln889Ter) led to a significant reduction of mRNA and protein expressions but formed stable truncated dimers with an increment of deubiquitinating enzyme activities and abnormal cellular aggregations, indicating a gain-of-function effect. The p.Gln889Ter and p.Leu1045del variants increased neuronal excitability in mouse brain, with a higher firing ability in p.Gln889Ter. These functional impairments align with the severity of the observed phenotypes, suggesting a genotype-phenotype correlation. Hence, a moderate association between USP25 and epilepsy was noted, indicating that USP25 is potentially a predisposing gene for epilepsy. Our results from Usp25 null mice and the patient-derived variants indicated that USP25 would play an epileptogenic role via loss-of-function or gain-of-function effects. The truncated variant p.Gln889Ter would have a profoundly different effect on epilepsy. Together, our results underscore the significance of USP25 heterozygous variants in epilepsy, thereby highlighting the critical role of USP25 in the brain.
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Epilepsia Generalizada , Ubiquitina Tiolesterasa , Humanos , Animales , Ubiquitina Tiolesterasa/genética , Ubiquitina Tiolesterasa/metabolismo , Femenino , Ratones , Masculino , Niño , Epilepsia Generalizada/genética , Adolescente , Lactante , Heterocigoto , Adulto Joven , Preescolar , Adulto , Secuenciación del Exoma , Estudios de Cohortes , Encéfalo/metabolismo , Encéfalo/patología , LinajeRESUMEN
A plethora of growth factors regulate keratinocyte proliferation and differentiation that control hair morphogenesis and skin barrier formation. Wavy hair phenotypes in mice result from naturally occurring loss-of-function mutations in the genes for TGF-alpha and EGFR. Conversely, excessive activities of TGF-alpha/EGFR result in hairless phenotypes and skin cancers. Unexpectedly, we found that mice lacking the Trpv3 gene also exhibit wavy hair coat and curly whiskers. Here we show that keratinocyte TRPV3, a member of the transient receptor potential (TRP) family of Ca(2+)-permeant channels, forms a signaling complex with TGF-alpha/EGFR. Activation of EGFR leads to increased TRPV3 channel activity, which in turn stimulates TGF-alpha release. TRPV3 is also required for the formation of the skin barrier by regulating the activities of transglutaminases, a family of Ca(2+)-dependent crosslinking enzymes essential for keratinocyte cornification. Our results show that a TRP channel plays a role in regulating growth factor signaling by direct complex formation.
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Receptores ErbB/metabolismo , Cabello/crecimiento & desarrollo , Transducción de Señal , Piel/crecimiento & desarrollo , Canales Catiónicos TRPV/metabolismo , Animales , Calcio/metabolismo , Células Cultivadas , Cabello/metabolismo , Humanos , Queratinocitos/metabolismo , Ratones , Ratones Noqueados , Piel/metabolismo , Canales Catiónicos TRPV/genética , Factor de Crecimiento Transformador alfa/metabolismoRESUMEN
Salmonella enterica, the etiological agent of gastrointestinal and systemic diseases, translocates a plethora of virulence factors through its type III secretion systems to host cells during infection. Among them, SpvB has been reported to harbor an ADP-ribosyltransferase domain in its C terminus, which destabilizes host cytoskeleton by modifying actin. However, whether this effector targets other host factors as well as the function of its N terminus still remains to be determined. Here, we found that SpvB targets clathrin and its adaptor AP-1 (adaptor protein 1) via interactions with its N-terminal domain. Notably, our data suggest that SpvB-clathrin/AP-1 associations disrupt clathrin-mediated endocytosis and protein secretion pathway as well. In addition, knocking down of AP-1 promotes Salmonella intracellular survival and proliferation in host cells.
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Salmonella enterica , Salmonella typhimurium , Salmonella typhimurium/metabolismo , Factor de Transcripción AP-1/metabolismo , Salmonella enterica/metabolismo , Factores de Virulencia/metabolismo , Actinas/metabolismo , Clatrina/metabolismoRESUMEN
Defense against ultraviolet (UV) radiation exposure is essential for survival, especially in high-elevation species. Although some specific genes involved in UV response have been reported, the full view of UV defense mechanisms remains largely unexplored. Herein, we used integrated approaches to analyze UV responses in the highest-elevation frog, Nanorana parkeri. We show less damage and more efficient antioxidant activity in skin of this frog than those of its lower-elevation relatives after UV exposure. We also reveal genes related to UV defense and a corresponding temporal expression pattern in N. parkeri. Genomic and metabolomic analysis along with large-scale transcriptomic profiling revealed a time-dependent coordinated defense mechanism in N. parkeri. We also identified several microRNAs that play important regulatory roles, especially in decreasing the expression levels of cell cycle genes. Moreover, multiple defense genes (i.e., TYR for melanogenesis) exhibit positive selection with function-enhancing substitutions. Thus, both expression shifts and gene mutations contribute to UV adaptation in N. parkeri. Our work demonstrates a genetic framework for evolution of UV defense in a natural environment.
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Anuros , Rayos Ultravioleta , Animales , Anuros/genética , Piel , Perfilación de la Expresión Génica , AntioxidantesRESUMEN
The current classification of acute myeloid leukemia (AML) relies largely on genomic alterations. Robust identification of clinically and biologically relevant molecular subtypes from nongenomic high-throughput sequencing data remains challenging. We established the largest multicenter AML cohort (n = 655) in China, with all patients subjected to RNA sequencing (RNA-Seq) and 619 (94.5%) to targeted or whole-exome sequencing (TES/WES). Based on an enhanced consensus clustering, eight stable gene expression subgroups (G1-G8) with unique clinical and biological significance were identified, including two unreported (G5 and G8) and three redefined ones (G4, G6, and G7). Apart from four well-known low-risk subgroups including PML::RARA (G1), CBFB::MYH11 (G2), RUNX1::RUNX1T1 (G3), biallelic CEBPA mutations or -like (G4), four meta-subgroups with poor outcomes were recognized. The G5 (myelodysplasia-related/-like) subgroup enriched clinical, cytogenetic and genetic features mimicking secondary AML, and hotspot mutations of IKZF1 (p.N159S) (n = 7). In contrast, most NPM1 mutations and KMT2A and NUP98 fusions clustered into G6-G8, showing high expression of HOXA/B genes and diverse differentiation stages, from hematopoietic stem/progenitor cell down to monocyte, namely HOX-primitive (G7), HOX-mixed (G8), and HOX-committed (G6). Through constructing prediction models, the eight gene expression subgroups could be reproduced in the Cancer Genome Atlas (TCGA) and Beat AML cohorts. Each subgroup was associated with distinct prognosis and drug sensitivities, supporting the clinical applicability of this transcriptome-based classification of AML. These molecular subgroups illuminate the complex molecular network of AML, which may promote systematic studies of disease pathogenesis and foster the screening of targeted agents based on omics.
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Leucemia Mieloide Aguda , Síndromes Mielodisplásicos , Humanos , Transcriptoma , Leucemia Mieloide Aguda/genética , Diferenciación Celular/genética , Células Madre HematopoyéticasRESUMEN
T cell acute lymphoblastic leukemia (T-ALL) is an aggressive hematological malignancy of T cell progenitors, known to be a heterogeneous disease in pediatric and adult patients. Here we attempted to better understand the disease at the molecular level based on the transcriptomic landscape of 707 T-ALL patients (510 pediatric, 190 adult patients, and 7 with unknown age; 599 from published cohorts and 108 newly investigated). Leveraging the information of gene expression enabled us to identify 10 subtypes (G1G10), including the previously undescribed one characterized by GATA3 mutations, with GATA3R276Q capable of affecting lymphocyte development in zebrafish. Through associating with T cell differentiation stages, we found that high expression of LYL1/LMO2/SPI1/HOXA (G1G6) might represent the early T cell progenitor, pro/precortical/cortical stage with a relatively high age of disease onset, and lymphoblasts with TLX3/TLX1 high expression (G7G8) could be blocked at the cortical/postcortical stage, while those with high expression of NKX2-1/TAL1/LMO1 (G9G10) might correspond to cortical/postcortical/mature stages of T cell development. Notably, adult patients harbored more cooperative mutations among epigenetic regulators, and genes involved in JAK-STAT and RAS signaling pathways, with 44% of patients aged 40 y or above in G1 bearing DNMT3A/IDH2 mutations usually seen in acute myeloid leukemia, suggesting the nature of mixed phenotype acute leukemia.
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Leucemia-Linfoma Linfoblástico de Células T Precursoras , Transcriptoma , Niño , Humanos , Mutación , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genéticaRESUMEN
BACKGROUND: Golidocitinib, a selective JAK1 tyrosine-kinase inhibitor, has shown encouraging anti-tumour activity in heavily pre-treated patients with relapsed or refractory peripheral T-cell lymphoma in a phase 1 study (JACKPOT8 Part A). Here, we report the full analysis of a phase 2 study, in which we assessed the anti-tumour activity of golidocitinib in a large multinational cohort of patients. METHODS: We did a single-arm, multinational, phase 2 trial (JACKPOT8 Part B) in 49 centres in Australia, China, South Korea, and the USA. Eligible patients were adults (aged ≥18 years) with relapsed or refractory peripheral T-cell lymphoma who had received at least one previous line of systemic therapy and an Eastern Cooperative Oncology Group performance status of 0-2. Patients were given oral golidocitinib 150 mg once daily until disease progression or other discontinuation criteria were met. The primary endpoint was the CT-based objective response rate, assessed by an independent review committee (IRC) per Lugano 2014 classification. The activity analysis set included all patients who received at least one dose and whose pathological diagnosis of peripheral T-cell lymphoma had been retrospectively confirmed by a central laboratory and who had at least one measurable lesion at baseline assessed by IRC. The safety analysis set included all patients who received at least one dose of study drug. This study is registered with ClinicalTrials.gov, NCT04105010, and is closed to accrual and follow-up is ongoing. FINDINGS: Between Feb 26, 2021, and Oct 12, 2022, we assessed 161 patients for eligibility, of whom 104 (65%) were enrolled and received at least one dose of study drug; the activity analysis set included 88 (85%) patients (median age 58 years [IQR 51-67], 57 [65%] of 88 were male, 31 [35%] were female, and 83 [94%] were Asian). As of data cutoff (Aug 31, 2023; median follow-up was 13·3 months [IQR 4·9-18·4]), per IRC assessment, the objective response rate was 44·3% (95% CI 33·7-55·3; 39 of 88 patients, p<0·0001), with 21 (24%) patients having a complete response and 18 (20%) having a partial response. In the safety analysis set, 61 (59%) of 104 patients had grade 3-4 drug-related treatment-emergent adverse events. The most common grade 3-4 drug-related treatment-emergent adverse events were neutrophil count decreased (30 [29%]), white blood cell count decreased (27 [26%]), lymphocyte count decreased (22 [21%]), and platelet count decreased (21 [20%]), which were clinically manageable and reversible. 25 (24%) patients had treatment-related serious adverse events. Deaths due to treatment-emergent adverse events occurred in three (3%) patients: two (2%) due to pneumonia (one case with fungal infection [related to golidocitinib] and another one with COVID-19 infection) and one (1%) due to confusional state. INTERPRETATION: In this phase 2 study, golidocitinib showed a favourable benefit-risk profile in treating relapsed or refractory peripheral T-cell lymphoma. The results of this study warrant further randomised clinical studies to confirm activity and assess efficacy in this population. FUNDING: Dizal Pharmaceutical.
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Linfoma de Células T Periférico , Adulto , Humanos , Masculino , Femenino , Adolescente , Persona de Mediana Edad , Linfoma de Células T Periférico/tratamiento farmacológico , Estudios Retrospectivos , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/patología , Progresión de la Enfermedad , Janus Quinasa 1/genética , Tirosina/uso terapéuticoRESUMEN
Recent studies have shown that nucleophagy can mitigate DNA damage by selectively degrading nuclear components protruding from the nucleus. However, little is known about the role of nucleophagy in neurons after spinal cord injury (SCI). Western blot analysis and immunofluorescence were performed to evaluate the nucleophagy after nuclear DNA damage and leakage in SCI neurons in vivo and NSC34 expression in primary neurons cultured with oxygen-glucose deprivation (OGD) in vitro, as well as the interaction and colocalization of autophagy protein LC3 with nuclear lamina protein Lamin B1. The effect of UBC9, a Small ubiquitin-related modifier (SUMO) E2 ligase, on Lamin B1 SUMOylation and nucleophagy was examined by siRNA transfection or 2-D08 (a small-molecule inhibitor of UBC9), immunoprecipitation, and immunofluorescence. In SCI and OGD injured NSC34 or primary cultured neurons, neuronal nuclear DNA damage induced the SUMOylation of Lamin B1, which was required by the nuclear Lamina accumulation of UBC9. Furthermore, LC3/Atg8, an autophagy-related protein, directly bound to SUMOylated Lamin B1, and delivered Lamin B1 to the lysosome. Knockdown or suppression of UBC9 with siRNA or 2-D08 inhibited SUMOylation of Lamin B1 and subsequent nucleophagy and protected against neuronal death. Upon neuronal DNA damage and leakage after SCI, SUMOylation of Lamin B1 is induced by nuclear Lamina accumulation of UBC9. Furthermore, it promotes LC3-Lamin B1 interaction to trigger nucleophagy that protects against neuronal DNA damage.
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Autofagia , Daño del ADN , Lamina Tipo B , Neuronas , Traumatismos de la Médula Espinal , Sumoilación , Enzimas Ubiquitina-Conjugadoras , Animales , Ratones , Núcleo Celular/metabolismo , Lamina Tipo B/metabolismo , Lamina Tipo B/genética , Neuronas/metabolismo , Neuronas/patología , Traumatismos de la Médula Espinal/metabolismo , Traumatismos de la Médula Espinal/genética , Traumatismos de la Médula Espinal/patología , Enzimas Ubiquitina-Conjugadoras/metabolismo , Enzimas Ubiquitina-Conjugadoras/genética , Ratones Endogámicos C57BL , Línea Celular TumoralRESUMEN
Protein post-translational modifications (PTMs), such as ADP-ribosylation and phosphorylation, regulate multiple fundamental biological processes in cells. During bacterial infection, effector proteins are delivered into host cells through dedicated bacterial secretion systems and can modulate important cellular pathways by covalently modifying their host targets. These strategies enable intruding bacteria to subvert various host processes, thereby promoting their own survival and proliferation. Despite rapid expansion of our understanding of effector-mediated PTMs in host cells, analytical measurements of these molecular events still pose significant challenges in the study of host-pathogen interactions. Nevertheless, with major technical breakthroughs in the last two decades, mass spectrometry (MS) has evolved to be a valuable tool for detecting protein PTMs and mapping modification sites. Additionally, large-scale PTM profiling, facilitated by different enrichment strategies prior to MS analysis, allows high-throughput screening of host enzymatic substrates of bacterial effectors. In this review, we summarize the advances in the studies of two representative PTMs (i.e., ADP-ribosylation and phosphorylation) catalyzed by bacterial effectors during infection. Importantly, we will discuss the ever-increasing role of MS in understanding these molecular events and how the latest MS-based tools can aid in future studies of this booming area of pathogenic bacteria-host interactions.
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Procesamiento Proteico-Postraduccional , Proteínas , Proteínas/metabolismo , Bacterias/metabolismo , Espectrometría de Masas/métodos , CatálisisRESUMEN
Large amounts of azurophilic granules are considered to be a morphological feature of acute promyelocytic leukaemia (APL). However, a small percentage of acute myeloid leukaemia (AML) patients also have a large number of azurophilic granules. A large cohort of 3210 AML patients in our hospital was screened to identify AML patients who had a large number of azurophilic granules. The clinical parameters of these patients were collected and compared with typical AML patients (control Group 1) and APL patients (control Group 2). The incidence of AML with a large number of azurophilic granules was 1.26%. The fibrinogen and D-dimer levels of patients in the study group were more similar to those of patients in control Group 2, as was the incidence of bleeding events. Additionally, patients in the study group had higher FLT3-ITD and NPM1 mutation rates than patients in control Group 1. Finally, patients in the study group had a higher 30-day mortality rate than those in control Group 2 (24.2% vs. 9.09%) and showed a higher 30-day mortality trend than those in control Group 1. Therefore, we should pay more attention to the prevention of coagulation dysfunction and bleeding events for these patients.
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Leucemia Mieloide Aguda , Nucleofosmina , Humanos , Masculino , Femenino , Persona de Mediana Edad , Leucemia Mieloide Aguda/mortalidad , Leucemia Mieloide Aguda/patología , Estudios Retrospectivos , Anciano , Adulto , Gránulos Citoplasmáticos/patología , Productos de Degradación de Fibrina-Fibrinógeno/análisis , Productos de Degradación de Fibrina-Fibrinógeno/metabolismo , Tirosina Quinasa 3 Similar a fms/genética , Mutación , Proteínas Nucleares/genética , Anciano de 80 o más Años , Adolescente , Adulto Joven , Fibrinógeno/análisis , Hemorragia/etiologíaRESUMEN
Gilteritinib, a potent FMS-like tyrosine kinase 3 (FLT3) inhibitor, was approved for relapsed/refractory (R/R) FLT3-mutated acute myeloid leukaemia (AML) patients but still showed limited efficacy. Here, we retrospectively analysed the efficacy and safety of different gilteritinib-based combination therapies (gilteritinib plus hypomethylating agent and venetoclax, G + HMA + VEN; gilteritinib plus HMA, G + HMA; gilteritinib plus venetoclax, G + VEN) in 33 R/R FLT3-mutated AML patients. The composite complete response (CRc) and modified CRc (mCRc) rates were 66.7% (12/18) and 88.9% (16/18) in patients received G + HMA + VEN, which was higher compared with that in G + HMA (CRc: 18.2%, 2/11; mCRc: 45.5%, 5/11) or G + VEN (CRc: 50.0%, 2/4; mCRc: 50.0%, 2/4). The median overall survival (OS) for G + HMA + VEN, G + HMA and G + VEN treatment was not reached, 160.0 days and 231.0 days. The median duration of remission (DOR) for G + HMA + VEN, G + HMA and G + VEN treatment was not reached, 82.0 days and 77.0 days. Four patients in the G + HMA + VEN group received alloHSCT after remission exhibited prolonged median DOR. The most common grade 3/4 adverse events were cytopenia, febrile neutropenia and pulmonary infection; there were no differences among the three groups. In conclusion, our data demonstrated promising response of G + HMA + VEN combination therapy in R/R FLT3-mutated AML, and it may be considered an effective therapy bridge to transplantation.
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Compuestos de Anilina , Compuestos Bicíclicos Heterocíclicos con Puentes , Leucemia Mieloide Aguda , Pirazinas , Sulfonamidas , Tirosina Quinasa 3 Similar a fms , Adulto , Humanos , Estudios RetrospectivosRESUMEN
A chemotherapy-based mobilization regimen in patients who mobilize poorly, based on etoposide, cytarabine and pegfilgrastim (EAP), has recently been introduced. The aim of this prospective study was to investigate the efficacy and safety of the EAP regimen in patients with poorly mobilizing multiple myeloma (MM) or lymphoma. This single-arm clinical trial was performed at eight public hospitals in China and was registered as a clinical trial (NCT05510089). The inclusion criteria were; (1) diagnosis of MM or lymphoma, (2) defined as a 'poor mobilizer' and (3) aged 18-75 years. The EAP regimen consisted of etoposide 75 mg/m2/day on days 1-2, cytarabine 300 mg/m2 every 12 h on days 1-2 and pegfilgrastim 6 mg on day 6. The primary endpoint of the study was the ratio of patients achieving adequate mobilization (≥2.0 × 106 CD34+ cells/kg). From 1 September 2022 to 15 August 2023, a total of 58 patients were enrolled, 53 (91.4%) achieved adequate mobilization, while 41 (70.7%) achieved optimal mobilization with a median number of cumulative collected CD34+ cells was 9.2 (range 2.1-92.7) × 106/kg and the median number of apheresis per patient of 1.2. The median time from administration of the EAP regimen to the first apheresis was 12 days. Approximately 8.6% of patients required plerixa for rescue, which was successful. Twelve (20.7%) of the 58 patients suffered grade 2-3 infections, while 25 (43.1%) required platelet transfusions. The duration of neutrophil and platelet engraftment was 11 days. In conclusion, these results suggest that the EAP mobilization regimen might be a promising option for poorly mobilizing patients with MM or lymphoma.
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Citarabina , Etopósido , Filgrastim , Movilización de Célula Madre Hematopoyética , Linfoma , Mieloma Múltiple , Polietilenglicoles , Humanos , Filgrastim/administración & dosificación , Filgrastim/uso terapéutico , Citarabina/administración & dosificación , Citarabina/uso terapéutico , Persona de Mediana Edad , Polietilenglicoles/administración & dosificación , Femenino , Masculino , Etopósido/administración & dosificación , Etopósido/uso terapéutico , Adulto , Linfoma/tratamiento farmacológico , Linfoma/terapia , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/terapia , Estudios Prospectivos , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Movilización de Célula Madre Hematopoyética/métodos , Adulto Joven , AdolescenteRESUMEN
Intervertebral disc degeneration (IVDD) is a complex process involving many factors, among which excessive senescence of nucleus pulposus cells is considered to be the main factor. Our previous study found that metformin can inhibit senescence in nucleus pulposus cells; however, the mechanism of such an action was still largely unknown. In the current study, we found that metformin inactivates the cGAS-STING pathway during oxidative stress. Furthermore, knockdown of STING (also known as STING1) suppresses senescence, indicating that metformin might exert its effect through the cGAS-STING pathway. Damaged DNA is a major inducer of the activation of the cGAS-STING pathway. Mechanistically, our study showed that DNA damage was reduced during metformin treatment; however, suppression of autophagy by 3-methyladenine (3-MA) treatment compromised the effect of metformin on DNA damage. In vivo studies also showed that 3-MA might diminish the therapeutic effect of metformin on IVDD. Taken together, our results reveal that metformin may suppress senescence via inactivating the cGAS-STING pathway through autophagy, implying a new application for metformin in cGAS-STING pathway-related diseases.
Asunto(s)
Degeneración del Disco Intervertebral , Metformina , Núcleo Pulposo , Autofagia/fisiología , Senescencia Celular/fisiología , Humanos , Degeneración del Disco Intervertebral/tratamiento farmacológico , Degeneración del Disco Intervertebral/genética , Degeneración del Disco Intervertebral/metabolismo , Proteínas de la Membrana , Metformina/metabolismo , Metformina/farmacología , Metformina/uso terapéutico , Nucleotidiltransferasas/genética , Nucleotidiltransferasas/metabolismo , Núcleo Pulposo/metabolismoRESUMEN
Starch is synthesized as insoluble, semicrystalline particles within plant chloroplast and amyloplast, which are referred to as starch grains (SGs). The size and morphology of SGs in the cereal endosperm are diverse and species-specific, representing a key determinant of the suitability of starch for industrial applications. However, the molecular mechanisms modulating SG size in cereal endosperm remain elusive. Here, we functionally characterized the rice (Oryza sativa) mutant substandard starch grain7 (ssg7), which exhibits enlarged SGs and defective endosperm development. SSG7 encodes a plant-specific DUF1001 domain-containing protein homologous to Arabidopsis (Arabidopsis thaliana) CRUMPLED LEAF (AtCRL). SSG7 localizes to the amyloplast membrane in developing endosperm. Several lines of evidence suggest that SSG7 functions together with SSG4 and SSG6, known as two regulators essential for SG development, to control SG size, by interacting with translocon-associated components, which unveils a molecular link between SG development and protein import. Genetically, SSG7 acts synergistically with SSG4 and appears to be functional redundancy with SSG6 in modulating SG size and endosperm development. Collectively, our findings uncover a multimeric functional protein complex involved in SG development in rice. SSG7 represents a promising target gene for the biotechnological modification of SG size, particularly for breeding programs aimed at improving starch quality.