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1.
Int J Mol Sci ; 25(9)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38731949

RESUMO

To enrich the properties of polylactic acid (PLA)-based composite films and improve the base degradability, in this study, a certain amount of poly(propylene carbonate) (PPC) was added to PLA-based composite films, and PLA/PPC-based composite films were prepared by melt blending and hot-press molding. The effects of the introduction of PPC on the composite films were analyzed through in-depth studies on mechanical properties, water vapor and oxygen transmission rates, thermal analysis, compost degradability, and bacterial inhibition properties of the composite films. When the introduction ratio coefficient of PPC was 30%, the tensile strength of the composite film increased by 19.68%, the water vapor transmission coefficient decreased by 14.43%, and the oxygen transmission coefficient decreased by 18.31% compared to that of the composite film without PPC, the cold crystallization temperature of the composite film increased gradually from 96.9 °C to 104.8 °C, and PPC improved the crystallization ability of composite film. The degradation rate of the composite film with PPC increased significantly compared to the previous one, and the degradation rate increased with the increase in the PPC content. The degradation rate was 49.85% and 46.22% faster on average than that of the composite film without PPC when the degradation was carried out over 40 and 80 days; the composite film had certain inhibition, and the maximum diameter of the inhibition circle was 2.42 cm. This study provides a strategy for the development of PLA-based biodegradable laminates, which can promote the application of PLA-based laminates in food packaging.


Assuntos
Poliésteres , Propano/análogos & derivados , Resistência à Tração , Poliésteres/química , Polipropilenos/química , Embalagem de Alimentos/métodos , Vapor , Polímeros/química , Antibacterianos/química , Antibacterianos/farmacologia , Temperatura
2.
Genes Dis ; 11(4): 101079, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38560501

RESUMO

CYP3A5 is a cytochrome P450 (CYP) enzyme that metabolizes drugs and contributes to drug resistance in cancer. However, it remains unclear whether CYP3A5 directly influences cancer progression. In this report, we demonstrate that CYP3A5 regulates glucose metabolism in pancreatic ductal adenocarcinoma. Multi-omics analysis showed that CYP3A5 knockdown results in a decrease in various glucose-related metabolites through its effect on glucose transport. A mechanistic study revealed that CYP3A5 enriches the glucose transporter GLUT1 at the plasma membrane by restricting the translation of TXNIP, a negative regulator of GLUT1. Notably, CYP3A5-generated reactive oxygen species were proved to be responsible for attenuating the AKT-4EBP1-TXNIP signaling pathway. CYP3A5 contributes to cell migration by maintaining high glucose uptake in pancreatic cancer. Taken together, our results, for the first time, reveal a role of CYP3A5 in glucose metabolism in pancreatic ductal adenocarcinoma and identify a novel mechanism that is a potential therapeutic target.

3.
Nat Commun ; 15(1): 3113, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600097

RESUMO

Autophagy is a conserved, catabolic process essential for maintaining cellular homeostasis. Malfunctional autophagy contributes to neurodevelopmental and neurodegenerative diseases. However, the exact role and targets of autophagy in human neurons remain elusive. Here we report a systematic investigation of neuronal autophagy targets through integrated proteomics. Deep proteomic profiling of multiple autophagy-deficient lines of human induced neurons, mouse brains, and brain LC3-interactome reveals roles of neuronal autophagy in targeting proteins of multiple cellular organelles/pathways, including endoplasmic reticulum (ER), mitochondria, endosome, Golgi apparatus, synaptic vesicle (SV) for degradation. By combining phosphoproteomics and functional analysis in human and mouse neurons, we uncovered a function of neuronal autophagy in controlling cAMP-PKA and c-FOS-mediated neuronal activity through selective degradation of the protein kinase A - cAMP-binding regulatory (R)-subunit I (PKA-RI) complex. Lack of AKAP11 causes accumulation of the PKA-RI complex in the soma and neurites, demonstrating a constant clearance of PKA-RI complex through AKAP11-mediated degradation in neurons. Our study thus reveals the landscape of autophagy degradation in human neurons and identifies a physiological function of autophagy in controlling homeostasis of PKA-RI complex and specific PKA activity in neurons.


Assuntos
Neurônios , Proteômica , Camundongos , Animais , Humanos , Neurônios/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Autofagia/fisiologia , Homeostase
4.
Elife ; 122024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38488852

RESUMO

Dysregulated pre-mRNA splicing and metabolism are two hallmarks of MYC-driven cancers. Pharmacological inhibition of both processes has been extensively investigated as potential therapeutic avenues in preclinical and clinical studies. However, how pre-mRNA splicing and metabolism are orchestrated in response to oncogenic stress and therapies is poorly understood. Here, we demonstrate that jumonji domain containing 6, arginine demethylase, and lysine hydroxylase, JMJD6, acts as a hub connecting splicing and metabolism in MYC-driven human neuroblastoma. JMJD6 cooperates with MYC in cellular transformation of murine neural crest cells by physically interacting with RNA binding proteins involved in pre-mRNA splicing and protein homeostasis. Notably, JMJD6 controls the alternative splicing of two isoforms of glutaminase (GLS), namely kidney-type glutaminase (KGA) and glutaminase C (GAC), which are rate-limiting enzymes of glutaminolysis in the central carbon metabolism in neuroblastoma. Further, we show that JMJD6 is correlated with the anti-cancer activity of indisulam, a 'molecular glue' that degrades splicing factor RBM39, which complexes with JMJD6. The indisulam-mediated cancer cell killing is at least partly dependent on the glutamine-related metabolic pathway mediated by JMJD6. Our findings reveal a cancer-promoting metabolic program is associated with alternative pre-mRNA splicing through JMJD6, providing a rationale to target JMJD6 as a therapeutic avenue for treating MYC-driven cancers.


Assuntos
Neuroblastoma , Precursores de RNA , Sulfonamidas , Humanos , Animais , Camundongos , Precursores de RNA/genética , Precursores de RNA/metabolismo , Glutaminase/genética , Reprogramação Metabólica , Histona Desmetilases com o Domínio Jumonji/metabolismo
5.
Cell Cycle ; 23(1): 15-35, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38252499

RESUMO

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer-related mortality worldwide. The oncogenic role of Matrin-3 (MATR3), an a nuclear matrix protein, in HCC remains largely unknown. Here, we document the biological function of MATR3 in HCC based on integrated bioinformatics analysis and functional studies. According to the TCGA database, MATR3 expression was found to be positively correlated with clinicopathological characteristics in HCC. The receiver operating characteristic (ROC) curve and Kaplan-Meier (KM) curve displayed the diagnostic and prognostic potentials of MATR3 in HCC patients, respectively. Pathway enrichment analysis represented the enrichment of MATR3 in various molecular pathways, including the regulation of the cell cycle. Functional assays in HCC cell lines showed reduced proliferation of cells with stable silencing of MATR3. At the same time, the suppressive effects of MATR3 depletion on HCC development were verified by xenograft tumor experiments. Moreover, MATR3 repression also resulted in cell cycle arrest by modulating the expression of cell cycle-associated genes. In addition, the interaction of MATR3 with cell cycle-regulating factors in HCC cells was further corroborated with co-immunoprecipitation and mass spectrometry (Co-IP/MS). Furthermore, CIBERSORT and TIMER analyses showed an association between MATR3 and immune infiltration in HCC. In general, this study highlights the novel oncogenic function of MATR3 in HCC, which could comprehensively address how aberrant changes in the cell cycle promote HCC development. MATR3 might serve as a prognostic predictor and therapeutic target for HCC patients.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Ciclo Celular/genética , Divisão Celular , Biomarcadores , Proteínas de Ligação a RNA , Proteínas Associadas à Matriz Nuclear/genética
6.
Nat Biomed Eng ; 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38036617

RESUMO

The limited availability of cytokines in solid tumours hinders maintenance of the antitumour activity of chimeric antigen receptor (CAR) T cells. Cytokine receptor signalling pathways in CAR T cells can be activated by transgenic expression or injection of cytokines in the tumour, or by engineering the activation of cognate cytokine receptors. However, these strategies are constrained by toxicity arising from the activation of bystander cells, by the suboptimal biodistribution of the cytokines and by downregulation of the cognate receptor. Here we show that replacement of the extracellular domains of heterodimeric cytokine receptors in T cells with two leucine zipper motifs provides optimal Janus kinase/signal transducer and activator of transcription signalling. Such chimeric cytokine receptors, which can be generated for common γ-chain receptors, interleukin-10 and -12 receptors, enabled T cells to survive cytokine starvation without induction of autonomous cell growth, and augmented the effector function of CAR T cells in vitro in the setting of chronic antigen exposure and in human tumour xenografts in mice. As a modular design, leucine zippers can be used to generate constitutively active cytokine receptors in effector immune cells.

7.
bioRxiv ; 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37425900

RESUMO

Dysregulated pre-mRNA splicing and metabolism are two hallmarks of MYC-driven cancers. Pharmacological inhibition of both processes has been extensively investigated as potential therapeutic avenues in preclinical and clinical studies. However, how pre-mRNA splicing and metabolism are orchestrated in response to oncogenic stress and therapies is poorly understood. Here, we demonstrate that Jumonji Domain Containing 6, Arginine Demethylase and Lysine Hydroxylase, JMJD6, acts as a hub connecting splicing and metabolism in MYC-driven neuroblastoma. JMJD6 cooperates with MYC in cellular transformation by physically interacting with RNA binding proteins involved in pre-mRNA splicing and protein homeostasis. Notably, JMJD6 controls the alternative splicing of two isoforms of glutaminase (GLS), namely kidney-type glutaminase (KGA) and glutaminase C (GAC), which are rate-limiting enzymes of glutaminolysis in the central carbon metabolism in neuroblastoma. Further, we show that JMJD6 is correlated with the anti-cancer activity of indisulam, a "molecular glue" that degrades splicing factor RBM39, which complexes with JMJD6. The indisulam-mediated cancer cell killing is at least partly dependent on the glutamine-related metabolic pathway mediated by JMJD6. Our findings reveal a cancer-promoting metabolic program is associated with alternative pre-mRNA splicing through JMJD6, providing a rationale to target JMJD6 as a therapeutic avenue for treating MYC-driven cancers.

8.
Commun Biol ; 6(1): 249, 2023 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-36882565

RESUMO

Prognosis of children with high-risk hepatoblastoma (HB), the most common pediatric liver cancer, remains poor. In this study, we found ribonucleotide reductase (RNR) subunit M2 (RRM2) was one of the key genes supporting cell proliferation in high-risk HB. While standard chemotherapies could effectively suppress RRM2 in HB cells, they induced a significant upregulation of the other RNR M2 subunit, RRM2B. Computational analysis revealed distinct signaling networks RRM2 and RRM2B were involved in HB patient tumors, with RRM2 supporting cell proliferation and RRM2B participating heavily in stress response pathways. Indeed, RRM2B upregulation in chemotherapy-treated HB cells promoted cell survival and subsequent relapse, during which RRM2B was gradually replaced back by RRM2. Combining an RRM2 inhibitor with chemotherapy showed an effective delaying of HB tumor relapse in vivo. Overall, our study revealed the distinct roles of the two RNR M2 subunits and their dynamic switching during HB cell proliferation and stress response.


Assuntos
Hepatoblastoma , Neoplasias Hepáticas , Criança , Humanos , Proliferação de Células , Doença Crônica , Hepatoblastoma/tratamento farmacológico , Hepatoblastoma/genética , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Recidiva , Ribonucleosídeo Difosfato Redutase/genética
9.
bioRxiv ; 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36747774

RESUMO

Prognosis of children with high-risk hepatoblastoma (HB), the most common pediatric liver cancer, remains poor. In this study, we found ribonucleotide reductase (RNR) subunit M2 ( RRM2 ) was one of the key genes supporting cell proliferation in high-risk HB. While standard chemotherapies could effectively suppress RRM2 in HB cells, they induced a significant upregulation of the other RNR M2 subunit, RRM2B . Computational analysis revealed distinct signaling networks RRM2 and RRM2B were involved in HB patient tumors, with RRM2 supporting cell proliferation and RRM2B participating heavily in stress response pathways. Indeed, RRM2B upregulation in chemotherapy-treated HB cells promoted cell survival and subsequent relapse, during which RRM2B was gradually replaced back by RRM2. Combining an RRM2 inhibitor with chemotherapy showed an effective delaying of HB tumor relapse in vivo. Overall, our study revealed the distinct roles of the two RNR M2 subunits and their dynamic switching during HB cell proliferation and stress response.

10.
Nat Cancer ; 4(2): 257-275, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36585452

RESUMO

Inhibiting individual histone deacetylase (HDAC) is emerging as well-tolerated anticancer strategy compared with pan-HDAC inhibitors. Through preclinical studies, we demonstrated that the sensitivity to the leading HDAC6 inhibitor (HDAC6i) ricolinstat can be predicted by a computational network-based algorithm (HDAC6 score). Analysis of ~3,000 human breast cancers (BCs) showed that ~30% of them could benefice from HDAC6i therapy. Thus, we designed a phase 1b dose-escalation clinical trial to evaluate the activity of ricolinostat plus nab-paclitaxel in patients with metastatic BC (MBC) (NCT02632071). Study results showed that the two agents can be safely combined, that clinical activity is identified in patients with HR+/HER2- disease and that the HDAC6 score has potential as predictive biomarker. Analysis of other tumor types also identified multiple cohorts with predicted sensitivity to HDAC6i's. Mechanistically, we have linked the anticancer activity of HDAC6i's to their ability to induce c-Myc hyperacetylation (ac-K148) promoting its proteasome-mediated degradation in sensitive cancer cells.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Desacetilase 6 de Histona/metabolismo , Neoplasias da Mama/tratamento farmacológico , Histona Desacetilases/metabolismo , Ácidos Hidroxâmicos/farmacologia , Ácidos Hidroxâmicos/uso terapêutico
11.
Sci Transl Med ; 14(653): eabq2096, 2022 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-35857643

RESUMO

Chimeric transcription factors drive lineage-specific oncogenesis but are notoriously difficult to target. Alveolar rhabdomyosarcoma (RMS) is an aggressive childhood soft tissue sarcoma transformed by the pathognomonic Paired Box 3-Forkhead Box O1 (PAX3-FOXO1) fusion protein, which governs a core regulatory circuitry transcription factor network. Here, we show that the histone lysine demethylase 4B (KDM4B) is a therapeutic vulnerability for PAX3-FOXO1+ RMS. Genetic and pharmacologic inhibition of KDM4B substantially delayed tumor growth. Suppression of KDM4 proteins inhibited the expression of core oncogenic transcription factors and caused epigenetic alterations of PAX3-FOXO1-governed superenhancers. Combining KDM4 inhibition with cytotoxic chemotherapy led to tumor regression in preclinical PAX3-FOXO1+ RMS subcutaneous xenograft models. In summary, we identified a targetable mechanism required for maintenance of the PAX3-FOXO1-related transcription factor network, which may translate to a therapeutic approach for fusion-positive RMS.


Assuntos
Rabdomiossarcoma Alveolar , Rabdomiossarcoma , Carcinogênese/genética , Linhagem Celular Tumoral , Criança , Proteína Forkhead Box O1/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Histona Desmetilases com o Domínio Jumonji/genética , Histona Desmetilases com o Domínio Jumonji/metabolismo , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Fator de Transcrição PAX3/genética , Fator de Transcrição PAX3/metabolismo , Fatores de Transcrição Box Pareados/genética , Fatores de Transcrição Box Pareados/metabolismo , Fatores de Transcrição Box Pareados/uso terapêutico , Rabdomiossarcoma/genética , Rabdomiossarcoma Alveolar/genética , Rabdomiossarcoma Alveolar/metabolismo , Rabdomiossarcoma Alveolar/patologia
12.
Int Immunopharmacol ; 110: 108999, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35858518

RESUMO

PURPOSE: The recognition of new diagnostic and prognostic biological markers for lung cancer is an essential and eager study. It's shown that ion channels play important roles in regulating various cellular processes and have been suggested to be associated with patient survival. However, tweety family member 3 (TTYH3), as a maxi-Cl- channel, its role in lung cancer remains elusive. METHODS: The expression, diagnostic and prognostic efficacy of TTYH3 were analyzed by public databases and clinical samples. Cell functional experiments were used to explore the effects of TTYH3 on cell viability. GO and KEGG enrichment analysis revealed underlying pathways that TTYH3 and its co-expressed genes were enriched in. TIMER, TIDE and R language analyses were used to detect the correlation between TTYH3 and immune infiltration cell and immunotherapy response. RESULTS: TTYH3 was up-regulated in lung cancer tissues compared to normal tissues and possessed a prominent diagnostic and prognostic value. TTYH3 knockdown significantly inhibited the proliferation of lung cancer cells. Enrichment analyses showed that TTYH3 and its co-expressed genes were mainly involved in immune related signaling pathways. Further investigation clarified that TTYH3 had a positive correlation with the infiltration of TAMs, Treg infiltration as well as T cell exhaustion and high TTYH3 expression indicated worse immunotherapy response and shorter survival after immune checkpoint blockade treatment. CONCLUSION: This study not only revealed the diagnostic and prognostic value of TTYH3 but also provided TTYH3-based estimation of immunotherapy response for lung cancer patients, which might provide new strategies like anti-TTYH3 combined with immune therapy for the treatment of lung cancer.


Assuntos
Neoplasias Pulmonares , Biomarcadores , Biomarcadores Tumorais/metabolismo , Humanos , Imunoterapia , Neoplasias Pulmonares/genética , Prognóstico
13.
J Hazard Mater ; 435: 129068, 2022 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-35650730

RESUMO

Frequent oil-spill accidents have posed serious threats to ecosystem balance and the efficiency of resources use. Hydrophobic adsorbents that can adsorb and recover oil without causing secondary pollution are ideal candidates for the remediation of oil contamination in water. However, these composites are inefficient for crude oil-spills cleanup because crude oil has low liquidity of at room temperature. Increasing the temperature can effectively enhance the flowability of crude oil. To achieve efficient crude-oil heating and removal in situ, wood aerogels were immersed in Ti3C2Tx suspensions and then coated with polydimethylsiloxane (PDMS) to obtain a solar-heated adsorbent (PT-WA). The prepared PT-WA exhibits super-hydrophobicity (water contact angle: 154° ± 2°), mechanical robustness (withstanding 20 loading-unloading cycles under 50% strain without structural damage), strong solar absorption, and favorable photothermal-conversion capability (rising to ~85 °C within 90 s under 1.5 sun). Owing to these advantages, PT-WA is an effective adsorbent for crude oil cleanup. In addition, a 'self-heating crude oil collector' was assembled for the fast adsorption and restoration of crude oil from the water surface. This solar-assisted self-heating sorbent offers a competitive platform for the cleanup and recycling of viscous crude oil spills.


Assuntos
Petróleo , Adsorção , Ecossistema , Calefação , Titânio , Água , Madeira
14.
Gene ; 835: 146651, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35688292

RESUMO

Esophageal squamous cell carcinoma (ESCC) is one of the leading causes of cancer-related mortality globally with a high risk of lymph node metastasis (LNM). In this study, weighted gene co-expression network analysis (WGCNA) showed the identification of 10 modules among which the significant module (turquoise), including 1352 genes, was correlated with LNM. A group 52 overlapping differentially expressed genes (DEGs) was identified based on the comparison of turquoise module with GSE23400 and GSE20347 datasets. Using Ctyohubba plugin, we identified 7 hub genes (ACTG2, SORBS1, MYH11, CXCL12, CNN1, IRS1 and CXCL8). IRS1 displayed significant correlation with metastasis. The decreased expression of IRS1 was also a predictor of poor OS of ESCC patients whereas the hub genes namely ACTG2, MYH11, CXCL8, CXCL12, IRS1 and CNN1 were associated with RFS of ESCC patients. These findings suggest that the altered expression of these hub genes are associated with prognosis and thus can be used as potential biomarkers for ESCC. Moreover, immunohistochemical staining and cell functional experiments displayed that the overexpression of IRS1 was negatively associated with metastasis in ESCC. In general, our research revealed several novel genes in ESCC especially the association of IRS1 with LNM in ESCC, which could provide novel insights into the initiation and progression of ESCC.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/genética , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/metabolismo , Perfilação da Expressão Gênica , Humanos , Proteínas Substratos do Receptor de Insulina/genética , Metástase Linfática
15.
ACS Nano ; 16(4): 6468-6479, 2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35413193

RESUMO

High-temperature oxidation mechanisms of metallic nanoparticles have been extensively investigated; however, it is challenging to determine whether the kinetic modeling is applicable at the nanoscale and how the differences in nanoparticle size influence the oxidation mechanisms. In this work, we study thermal oxidation of pristine Ni nanoparticles ranging from 4 to 50 nm in 1 bar 1%O2/N2 at 600 °C using in situ gas-cell environmental transmission electron microscopy. Real-space in situ oxidation videos revealed an unexpected nanoparticle surface refacetting before oxidation and a strong Ni nanoparticle size dependence, leading to distinct structural development during the oxidation and different final NiO morphology. By quantifying the NiO thickness/volume change in real space, individual nanoparticle-level oxidation kinetics was established and directly correlated with nanoparticle microstructural evolution with specified fast and slow oxidation directions. Thus, for the size-dependent Ni nanoparticle oxidation, we propose a unified oxidation theory with a two-stage oxidation process: stage 1: dominated by the early NiO nucleation (Avrami-Erofeev model) and stage 2: the Wagner diffusion-balanced NiO shell thickening (Wanger model). In particular, to what extent the oxidation would proceed into stage 2 dictates the final NiO morphology, which depends on the Ni starting radius with respect to the critical thickness under given oxidation conditions. The overall oxidation duration is controlled by both the diffusivity of Ni2+ in NiO and the Ni in Ni self-diffusion. We also compare the single-particle kinetic curve with the collective one and discuss the effects of nanoparticle size differences on kinetic model analysis.

16.
J Biol Chem ; 298(3): 101590, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35033535

RESUMO

Ribosomal RNAs (rRNAs) have long been known to carry chemical modifications, including 2'O-methylation, pseudouridylation, N6-methyladenosine (m6A), and N6,6-dimethyladenosine. While the functions of many of these modifications are unclear, some are highly conserved and occur in regions of the ribosome critical for mRNA decoding. Both 28S rRNA and 18S rRNA carry single m6A sites, and while the methyltransferase ZCCHC4 has been identified as the enzyme responsible for the 28S rRNA m6A modification, the methyltransferase responsible for the 18S rRNA m6A modification has remained unclear. Here, we show that the METTL5-TRMT112 methyltransferase complex installs the m6A modification at position 1832 of human 18S rRNA. Our work supports findings that TRMT112 is required for METTL5 stability and reveals that human METTL5 mutations associated with microcephaly and intellectual disability disrupt this interaction. We show that loss of METTL5 in human cancer cell lines and in mice regulates gene expression at the translational level; additionally, Mettl5 knockout mice display reduced body size and evidence of metabolic defects. While recent work has focused heavily on m6A modifications in mRNA and their roles in mRNA processing and translation, we demonstrate here that deorphanizing putative methyltransferase enzymes can reveal previously unappreciated regulatory roles for m6A in noncoding RNAs.


Assuntos
Metiltransferases , RNA Mensageiro , RNA Ribossômico 18S , Adenosina/análogos & derivados , Animais , Metilação , Metiltransferases/genética , Metiltransferases/metabolismo , Camundongos , Biossíntese de Proteínas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Ribossômico 18S/genética , RNA Ribossômico 18S/metabolismo , RNA Ribossômico 28S/metabolismo
17.
Cancers (Basel) ; 13(13)2021 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-34202615

RESUMO

Acute Myeloid Leukemia (AML) is a heterogeneous disease with several recurrent cytogenetic abnormalities. Despite genomics and transcriptomics profiling efforts to understand AML's heterogeneity, studies focused on the proteomic profiles associated with pediatric AML cytogenetic features remain limited. Furthermore, the majority of biological functions within cells are operated by proteins (i.e., enzymes) and most drugs target the proteome rather than the genome or transcriptome, thus, highlighting the significance of studying proteomics. Here, we present our results from a pilot study investigating global proteomic profiles of leukemic cells obtained at diagnosis from 16 pediatric AML patients using a robust TMT-LC/LC-MS/MS platform. The proteome profiles were compared among patients with or without core binding factor (CBF) translocation indicated by a t(8;21) or inv(16) cytogenetic abnormality, minimal residual disease status at the end of the first cycle of chemotherapy (MRD1), and in vitro chemosensitivity of leukemic cells to cytarabine (Ara-C LC50). Our results established proteomic differences between CBF and non-CBF AML subtypes, providing insights to AML subtypes physiology, and identified potential druggable proteome targets such as THY1 (CD90), NEBL, CTSF, COL2A1, CAT, MGLL (MAGL), MACROH2A2, CLIP2 (isoform 1 and 2), ANPEP (CD13), MMP14, and AK5.

18.
Cell Rep ; 31(13): 107819, 2020 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-32610122

RESUMO

The RNA N6-methyladenosine (m6A) methylation is installed by the METTL3-METTL14 methyltransferase complex. This modification has critical regulatory roles in various biological processes. Here, we report that deletion of Mettl14 dramatically reduces mRNA m6A methylation in developing B cells and severely blocks B cell development in mice. Deletion of Mettl14 impairs interleukin-7 (IL-7)-induced pro-B cell proliferation and the large-pre-B-to-small-pre-B transition and causes dramatic abnormalities in gene expression programs important for B cell development. Suppression of a group of transcripts by cytoplasmic m6A reader YTHDF2 is critical to the IL-7-induced pro-B cell proliferation. In contrast, the block in the large-pre-B-to-small-pre-B transition is independent of YTHDF1 or YTHDF2 but is associated with a failure to properly upregulate key transcription factors regulating this transition. Our data highlight the important regulatory roles of the RNA m6A methylation and its reader proteins in early B cell development.


Assuntos
Adenosina/análogos & derivados , Linfócitos B/metabolismo , RNA/metabolismo , Adenosina/metabolismo , Animais , Sequência de Bases , Proliferação de Células , Tamanho Celular , Cromatina/metabolismo , Cadeias Pesadas de Imunoglobulinas/metabolismo , Cadeias Leves de Imunoglobulina/metabolismo , Interleucina-7/metabolismo , Metilação , Metiltransferases/deficiência , Metiltransferases/metabolismo , Camundongos Knockout , Ligação Proteica , Biossíntese de Proteínas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo , Fatores de Transcrição/metabolismo , Ativação Transcricional/genética
19.
Anal Chem ; 92(10): 7162-7170, 2020 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-32343560

RESUMO

Multiplexed isobaric labeling methods, such as tandem mass tags (TMT), remarkably improve the throughput of quantitative mass spectrometry. Here, we present a 27-plex TMT method coupled with two-dimensional liquid chromatography (LC/LC) for extensive peptide fractionation and high-resolution tandem mass spectrometry (MS/MS) for peptide quantification and then apply the method to profile the complex human brain proteome of Alzheimer's disease (AD). The 27-plex method combines multiplexed capacities of the 11-plex and the 16-plex TMT, as the peptides labeled by the two TMT sets display different mass and hydrophobicity, which can be well separated in LC-MS/MS. We first systematically optimized the protocol for the newly developed 16-plex TMT, including labeling reaction, desalting, and MS conditions, and then directly compared the 11-plex and 16-plex methods by analyzing the same human AD samples. Both methods yielded similar proteome coverage, analyzing >100 000 peptides in >10 000 human proteins. Furthermore, the 11-plex and 16-plex samples were mixed for a 27-plex assay, resulting in more than 8000 protein measurements within the same MS time. The 27-plex results are highly consistent with those of the individual 11-plex and 16-plex TMT analyses. We also used these proteomics data sets to compare the AD brain with the nondementia controls, discovering major AD-related proteins and revealing numerous novel protein alterations enriched in the pathways of amyloidosis, immunity, mitochondrial, and synaptic functions. Overall, our data strongly demonstrate that this new 27-plex strategy is highly feasible for routine large-scale proteomic analysis.


Assuntos
Doença de Alzheimer/diagnóstico , Lobo Frontal/química , Proteoma/análise , Cromatografia Líquida , Humanos , Peptídeos/análise , Espectrometria de Massas em Tandem
20.
J Int Med Res ; 48(3): 300060519889191, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31847654

RESUMO

OBJECTIVE: To investigate the clinical efficacy of laparoscopic gastrointestinal emergency surgery and postoperative complications. METHODS: Data for 604 patients undergoing emergency gastrointestinal surgery between January 2013 and December 2018 were analyzed retrospectively. Treatment efficacy and postoperative complications were compared between 300 patients (control group) undergoing traditional laparotomy and 304 patients (observation group) undergoing laparoscopic surgery. RESULTS: Clinical features were significantly better in the observation group than in the control group, including duration of surgery (59.12 ± 10.31 minutes vs. 70.34 ± 12.83 minutes), intraoperative blood loss (41.21 ± 10.45 mL vs. 61.38 ± 9.97 mL), postoperative pain score (1.25 ± 0.25 points. vs. 5.13 ± 0.43 points), length of hospital stay (5.13 ± 0.24 days vs. 7.05 ± 0.13 days), and time to free activity (13 ± 2.96 hours vs. 22 ± 3.02 hours). The total complication incidence in the observation group was 3.9%, compared with 16% in the control group (16%). No significant differences in direct medical costs were recorded between the observation and control groups. CONCLUSIONS: For patients undergoing emergency gastrointestinal surgery, laparoscopic surgery resulted in better clinical outcomes than traditional laparotomy without incurring additional costs. The potential clinical benefits of emergency laparoscopic gastrointestinal surgery warrant further study.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório , Laparoscopia , Humanos , Laparotomia , Tempo de Internação , Complicações Pós-Operatórias , Estudos Retrospectivos , Resultado do Tratamento
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