RESUMO
Although mutations in DNA are the best-studied source of neoantigens that determine response to immune checkpoint blockade, alterations in RNA splicing within cancer cells could similarly result in neoepitope production. However, the endogenous antigenicity and clinical potential of such splicing-derived epitopes have not been tested. Here, we demonstrate that pharmacologic modulation of splicing via specific drug classes generates bona fide neoantigens and elicits anti-tumor immunity, augmenting checkpoint immunotherapy. Splicing modulation inhibited tumor growth and enhanced checkpoint blockade in a manner dependent on host T cells and peptides presented on tumor MHC class I. Splicing modulation induced stereotyped splicing changes across tumor types, altering the MHC I-bound immunopeptidome to yield splicing-derived neoepitopes that trigger an anti-tumor T cell response in vivo. These data definitively identify splicing modulation as an untapped source of immunogenic peptides and provide a means to enhance response to checkpoint blockade that is readily translatable to the clinic.
Assuntos
Neoplasias/genética , Neoplasias/imunologia , Splicing de RNA/genética , Animais , Apresentação de Antígeno/efeitos dos fármacos , Apresentação de Antígeno/imunologia , Antígenos de Neoplasias/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Epitopos/imunologia , Etilenodiaminas/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Hematopoese/efeitos dos fármacos , Hematopoese/genética , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Imunoterapia , Inflamação/patologia , Camundongos Endogâmicos C57BL , Peptídeos/metabolismo , Isoformas de Proteínas/metabolismo , Pirróis/farmacologia , Splicing de RNA/efeitos dos fármacos , Sulfonamidas/farmacologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologiaRESUMO
PGC-1α is well established as a metazoan transcriptional coactivator of cellular adaptation in response to stress. However, the mechanisms by which PGC-1α activates gene transcription are incompletely understood. Here, we report that PGC-1α serves as a scaffold protein that physically and functionally connects the DNA-binding protein estrogen-related receptor α (ERRα), cap-binding protein 80 (CBP80), and Mediator to overcome promoter-proximal pausing of RNAPII and transcriptionally activate stress-response genes. We show that PGC-1α promotes pausing release in a two-arm mechanism (1) by recruiting the positive transcription elongation factor b (P-TEFb) and (2) by outcompeting the premature transcription termination complex Integrator. Using mice homozygous for five amino acid changes in the CBP80-binding motif (CBM) of PGC-1α that destroy CBM function, we show that efficient differentiation of primary myoblasts to myofibers and timely skeletal muscle regeneration after injury require PGC-1α binding to CBP80. Our findings reveal how PGC-1α activates stress-response gene transcription in a previously unanticipated pre-mRNA quality-control pathway.
Assuntos
Precursores de RNA , Fatores de Transcrição , Animais , Camundongos , Proteínas de Ligação a DNA/genética , Músculo Esquelético/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Regiões Promotoras Genéticas , Proteínas de Ligação ao Cap de RNA/genética , RNA Polimerase II/metabolismo , Precursores de RNA/metabolismo , Fatores de Transcrição/metabolismo , Transcrição GênicaRESUMO
Despite a long appreciation for the role of nonsense-mediated mRNA decay (NMD) in destroying faulty, disease-causing mRNAs and maintaining normal, physiologic mRNA abundance, additional effectors that regulate NMD activity in mammalian cells continue to be identified. Here, we describe a haploid-cell genetic screen for NMD effectors that has unexpectedly identified 13 proteins constituting the AKT signaling pathway. We show that AKT supersedes UPF2 in exon-junction complexes (EJCs) that are devoid of RNPS1 but contain CASC3, defining an unanticipated insulin-stimulated EJC. Without altering UPF1 RNA binding or ATPase activity, AKT-mediated phosphorylation of the UPF1 CH domain at T151 augments UPF1 helicase activity, which is critical for NMD and also decreases the dependence of helicase activity on ATP. We demonstrate that upregulation of AKT signaling contributes to the hyperactivation of NMD that typifies Fragile X syndrome, as exemplified using FMR1-KO neural stem cells derived from induced pluripotent stem cells.
Assuntos
Degradação do RNAm Mediada por Códon sem Sentido , Proteínas Proto-Oncogênicas c-akt , Animais , Códon sem Sentido/genética , Éxons/genética , Mamíferos/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Helicases/genética , RNA Helicases/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transativadores/genética , Transativadores/metabolismo , Fatores de Transcrição/metabolismoRESUMO
Although peroxisome proliferator-activated receptor-γ (PPARγ) coactivator 1α (PGC-1α) is a well-established transcriptional coactivator for the metabolic adaptation of mammalian cells to diverse physiological stresses, the molecular mechanism by which it functions is incompletely understood. Here we used in vitro binding assays, X-ray crystallography, and immunoprecipitations of mouse myoblast cell lysates to define a previously unknown cap-binding protein 80 (CBP80)-binding motif (CBM) in the C terminus of PGC-1α. We show that the CBM, which consists of a nine-amino-acid α helix, is critical for the association of PGC-1α with CBP80 at the 5' cap of target transcripts. Results from RNA sequencing demonstrate that the PGC-1α CBM promotes RNA synthesis from promyogenic genes. Our findings reveal a new conduit between DNA-associated and RNA-associated proteins that functions in a cap-binding protein surveillance mechanism, without which efficient differentiation of myoblasts to myotubes fails to occur.
Assuntos
Complexo Proteico Nuclear de Ligação ao Cap/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/química , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Ativação Transcricional , Animais , Proteínas de Transporte/química , Proteínas de Transporte/metabolismo , Diferenciação Celular , Humanos , Células MCF-7 , Camundongos , Fibras Musculares Esqueléticas/metabolismo , Mioblastos/citologia , Mioblastos/metabolismo , Conformação Proteica em alfa-Hélice , Domínios e Motivos de Interação entre Proteínas , Capuzes de RNA/metabolismo , Proteínas de Ligação a RNA , Transcrição GênicaRESUMO
BACKGROUND: Covalent (irreversible) Bruton's tyrosine kinase (BTK) inhibitors have transformed the treatment of multiple B-cell cancers, especially chronic lymphocytic leukemia (CLL). However, resistance can arise through multiple mechanisms, including acquired mutations in BTK at residue C481, the binding site of covalent BTK inhibitors. Noncovalent (reversible) BTK inhibitors overcome this mechanism and other sources of resistance, but the mechanisms of resistance to these therapies are currently not well understood. METHODS: We performed genomic analyses of pretreatment specimens as well as specimens obtained at the time of disease progression from patients with CLL who had been treated with the noncovalent BTK inhibitor pirtobrutinib. Structural modeling, BTK-binding assays, and cell-based assays were conducted to study mutations that confer resistance to noncovalent BTK inhibitors. RESULTS: Among 55 treated patients, we identified 9 patients with relapsed or refractory CLL and acquired mechanisms of genetic resistance to pirtobrutinib. We found mutations (V416L, A428D, M437R, T474I, and L528W) that were clustered in the kinase domain of BTK and that conferred resistance to both noncovalent BTK inhibitors and certain covalent BTK inhibitors. Mutations in BTK or phospholipase C gamma 2 (PLCγ2), a signaling molecule and downstream substrate of BTK, were found in all 9 patients. Transcriptional activation reflecting B-cell-receptor signaling persisted despite continued therapy with noncovalent BTK inhibitors. CONCLUSIONS: Resistance to noncovalent BTK inhibitors arose through on-target BTK mutations and downstream PLCγ2 mutations that allowed escape from BTK inhibition. A proportion of these mutations also conferred resistance across clinically approved covalent BTK inhibitors. These data suggested new mechanisms of genomic escape from established covalent and novel noncovalent BTK inhibitors. (Funded by the American Society of Hematology and others.).
Assuntos
Tirosina Quinase da Agamaglobulinemia , Resistencia a Medicamentos Antineoplásicos , Leucemia Linfocítica Crônica de Células B , Mutação , Fosfolipase C gama , Inibidores de Proteínas Quinases , Humanos , Pessoa de Meia-Idade , Adenina/análogos & derivados , Adenina/farmacologia , Tirosina Quinase da Agamaglobulinemia/antagonistas & inibidores , Tirosina Quinase da Agamaglobulinemia/genética , Tirosina Quinase da Agamaglobulinemia/ultraestrutura , Resistencia a Medicamentos Antineoplásicos/genética , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Fosfolipase C gama/genética , Piperidinas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Receptores de Antígenos de Linfócitos B/metabolismo , Análise de Sequência de RNA , Transdução de Sinais/efeitos dos fármacosRESUMO
Histiocytic neoplasms are a heterogeneous group of clonal haematopoietic disorders that are marked by diverse mutations in the mitogen-activated protein kinase (MAPK) pathway1,2. For the 50% of patients with histiocytosis who have BRAFV600 mutations3-5, RAF inhibition is highly efficacious and has markedly altered the natural history of the disease6,7. However, no standard therapy exists for the remaining 50% of patients who lack BRAFV600 mutations. Although ERK dependence has been hypothesized to be a consistent feature across histiocytic neoplasms, this remains clinically unproven and many of the kinase mutations that are found in patients who lack BRAFV600 mutations have not previously been biologically characterized. Here we show ERK dependency in histiocytoses through a proof-of-concept clinical trial of cobimetinib, an oral inhibitor of MEK1 and MEK2, in patients with histiocytoses. Patients were enrolled regardless of their tumour genotype. In parallel, MAPK alterations that were identified in treated patients were characterized for their ability to activate ERK. In the 18 patients that we treated, the overall response rate was 89% (90% confidence interval of 73-100). Responses were durable, with no acquired resistance to date. At one year, 100% of responses were ongoing and 94% of patients remained progression-free. Cobimetinib treatment was efficacious regardless of genotype, and responses were observed in patients with ARAF, BRAF, RAF1, NRAS, KRAS, MEK1 (also known as MAP2K1) and MEK2 (also known as MAP2K2) mutations. Consistent with the observed responses, the characterization of the mutations that we identified in these patients confirmed that the MAPK-pathway mutations were activating. Collectively, these data demonstrate that histiocytic neoplasms are characterized by a notable dependence on MAPK signalling-and that they are consequently responsive to MEK inhibition. These results extend the benefits of molecularly targeted therapy to the entire spectrum of patients with histiocytosis.
Assuntos
Azetidinas/uso terapêutico , Transtornos Histiocíticos Malignos/tratamento farmacológico , Transtornos Histiocíticos Malignos/enzimologia , Histiocitose/tratamento farmacológico , Histiocitose/enzimologia , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Piperidinas/uso terapêutico , Azetidinas/farmacologia , Transtornos Histiocíticos Malignos/genética , Transtornos Histiocíticos Malignos/patologia , Histiocitose/genética , Histiocitose/patologia , Humanos , MAP Quinase Quinase 1/antagonistas & inibidores , MAP Quinase Quinase 2/antagonistas & inibidores , MAP Quinase Quinase 2/genética , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Mutação , Piperidinas/farmacologia , Intervalo Livre de Progressão , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas c-raf/genéticaRESUMO
SF3B1 is the most commonly mutated RNA splicing factor in cancer1-4, but the mechanisms by which SF3B1 mutations promote malignancy are poorly understood. Here we integrated pan-cancer splicing analyses with a positive-enrichment CRISPR screen to prioritize splicing alterations that promote tumorigenesis. We report that diverse SF3B1 mutations converge on repression of BRD9, which is a core component of the recently described non-canonical BAF chromatin-remodelling complex that also contains GLTSCR1 and GLTSCR1L5-7. Mutant SF3B1 recognizes an aberrant, deep intronic branchpoint within BRD9 and thereby induces the inclusion of a poison exon that is derived from an endogenous retroviral element and subsequent degradation of BRD9 mRNA. Depletion of BRD9 causes the loss of non-canonical BAF at CTCF-associated loci and promotes melanomagenesis. BRD9 is a potent tumour suppressor in uveal melanoma, such that correcting mis-splicing of BRD9 in SF3B1-mutant cells using antisense oligonucleotides or CRISPR-directed mutagenesis suppresses tumour growth. Our results implicate the disruption of non-canonical BAF in the diverse cancer types that carry SF3B1 mutations and suggest a mechanism-based therapeutic approach for treating these malignancies.
Assuntos
Proteínas Cromossômicas não Histona/metabolismo , Neoplasias/genética , Splicing de RNA , Spliceossomos/metabolismo , Animais , Linhagem Celular Tumoral , Montagem e Desmontagem da Cromatina/genética , Proteínas Cromossômicas não Histona/genética , Humanos , Camundongos , Transplante de Neoplasias , Neoplasias/patologia , Fosfoproteínas/metabolismo , Fatores de Processamento de RNA/metabolismo , Spliceossomos/genética , Fatores de Transcrição/metabolismoRESUMO
Transcription and pre-mRNA splicing are key steps in the control of gene expression and mutations in genes regulating each of these processes are common in leukaemia1,2. Despite the frequent overlap of mutations affecting epigenetic regulation and splicing in leukaemia, how these processes influence one another to promote leukaemogenesis is not understood and, to our knowledge, there is no functional evidence that mutations in RNA splicing factors initiate leukaemia. Here, through analyses of transcriptomes from 982 patients with acute myeloid leukaemia, we identified frequent overlap of mutations in IDH2 and SRSF2 that together promote leukaemogenesis through coordinated effects on the epigenome and RNA splicing. Whereas mutations in either IDH2 or SRSF2 imparted distinct splicing changes, co-expression of mutant IDH2 altered the splicing effects of mutant SRSF2 and resulted in more profound splicing changes than either mutation alone. Consistent with this, co-expression of mutant IDH2 and SRSF2 resulted in lethal myelodysplasia with proliferative features in vivo and enhanced self-renewal in a manner not observed with either mutation alone. IDH2 and SRSF2 double-mutant cells exhibited aberrant splicing and reduced expression of INTS3, a member of the integrator complex3, concordant with increased stalling of RNA polymerase II (RNAPII). Aberrant INTS3 splicing contributed to leukaemogenesis in concert with mutant IDH2 and was dependent on mutant SRSF2 binding to cis elements in INTS3 mRNA and increased DNA methylation of INTS3. These data identify a pathogenic crosstalk between altered epigenetic state and splicing in a subset of leukaemias, provide functional evidence that mutations in splicing factors drive myeloid malignancy development, and identify spliceosomal changes as a mediator of IDH2-mutant leukaemogenesis.
Assuntos
Processamento Alternativo/genética , Carcinogênese/genética , Epigênese Genética , Leucemia Mieloide Aguda/genética , Animais , Linhagem Celular Tumoral , Proliferação de Células , Metilação de DNA , Proteínas de Ligação a DNA/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Isocitrato Desidrogenase/genética , Masculino , Mutação/genética , RNA Polimerase II/metabolismo , Fatores de Processamento de Serina-Arginina/genética , TranscriptomaRESUMO
SignificanceThe GGGGCC hexanucleotide repeat expansion in the chromosome 9 open reading frame 72 (C9orf72) gene is the most common genetic cause of amyotrophic lateral sclerosis (ALS). Despite myriad studies on the toxic effects of poly-dipeptides produced from the C9orf72 repeats, the mechanisms underlying the selective hyperexcitability of motor cortex that characterizes the early stages of C9orf72 ALS patients remain elusive. Here, we show that the proline-arginine poly-dipeptides cause hyperexcitability in cortical motor neurons by increasing persistent sodium currents conducted by the Nav1.2/ß4 sodium channel complex, which is highly expressed in the motor cortex. These findings provide the basis for understanding how the C9orf72 mutation causes motor neuron hyperactivation that can lead to the motor neuron death in C9orf72 ALS.
Assuntos
Esclerose Lateral Amiotrófica/etiologia , Esclerose Lateral Amiotrófica/metabolismo , Proteína C9orf72/genética , Dipeptídeos/genética , Hipercinese/genética , Neurônios Motores/metabolismo , Esclerose Lateral Amiotrófica/patologia , Arginina , Córtex Cerebral/metabolismo , Córtex Cerebral/fisiopatologia , Dipeptídeos/metabolismo , Suscetibilidade a Doenças , Potencial Evocado Motor , Predisposição Genética para Doença , Humanos , Fenótipo , Prolina , Sódio/metabolismoRESUMO
Detailed genomic and epigenomic analyses of MECOM (the MDS1 and EVI1 complex locus) have revealed that inversion or translocation of chromosome 3 drives inv(3)/t(3;3) myeloid leukemias via structural rearrangement of an enhancer that upregulates transcription of EVI1. Here, we identify a novel, previously unannotated oncogenic RNA-splicing derived isoform of EVI1 that is frequently present in inv(3)/t(3;3) acute myeloid leukemia (AML) and directly contributes to leukemic transformation. This EVI1 isoform is generated by oncogenic mutations in the core RNA splicing factor SF3B1, which is mutated in >30% of inv(3)/t(3;3) myeloid neoplasm patients and thereby represents the single most commonly cooccurring genomic alteration in inv(3)/t(3;3) patients. SF3B1 mutations are statistically uniquely enriched in inv(3)/t(3;3) myeloid neoplasm patients and patient-derived cell lines compared with other forms of AML and promote mis-splicing of EVI1 generating an in-frame insertion of 6 amino acids at the 3' end of the second zinc finger domain of EVI1. Expression of this EVI1 splice variant enhanced the self-renewal of hematopoietic stem cells, and introduction of mutant SF3B1 in mice bearing the humanized inv(3)(q21q26) allele resulted in generation of this novel EVI1 isoform in mice and hastened leukemogenesis in vivo. The mutant SF3B1 spliceosome depends upon an exonic splicing enhancer within EVI1 exon 13 to promote usage of a cryptic branch point and aberrant 3' splice site within intron 12 resulting in the generation of this isoform. These data provide a mechanistic basis for the frequent cooccurrence of SF3B1 mutations as well as new insights into the pathogenesis of myeloid leukemias harboring inv(3)/t(3;3).
Assuntos
Leucemia Mieloide Aguda , Proto-Oncogenes , Animais , Inversão Cromossômica , Cromossomos Humanos Par 3/metabolismo , Proteínas de Ligação a DNA/metabolismo , Humanos , Leucemia Mieloide Aguda/patologia , Proteína do Locus do Complexo MDS1 e EVI1/genética , Camundongos , Proto-Oncogenes/genética , Fatores de Transcrição/metabolismoRESUMO
REV-ERBα and its paralog, REV-ERBß, encoded by NR1D1 and NR1D2 genes, are key nuclear receptors that link the circadian timing system and metabolic homeostasis. Since heme is an endogenous ligand, REV-ERBs have been considered key components of the circadian molecular clock and can be pharmacologically targeted to treat various circadian rhythm-related diseases, such as cardiometabolic, inflammatory, and neuropsychiatric diseases, as well as cancer. REV-ERBs are believed to be functionally redundant and compensatory, although they often affect the expression of gene subsets in an isoform-specific manner. Therefore, this study aimed to identify the redundant and distinct roles of each isoform in controlling its target genes by comparing the transcriptome profiles of a panel of mutant U2OS human osteosarcoma cells in which either NR1D1 or NR1D2 was ablated. Indeed, our transcriptomic analyses revealed that most REV-ERB-regulated genes are controlled by redundant or even additive actions. However, the RNA expression profiles of each single mutant cell line also provide strong evidence for isoform-dependent actions. For example, REV-ERBα is more responsible for regulating the NF-κΒ signaling pathway, whereas a group of extracellular matrix components requires REV-ERBß to maintain their expression. We found that REV-ERBs have isoform-selective functions in the regulation of certain circadian output pathways despite their overlapping roles in the circadian molecular clock. Thus, the development of isoform-selective REV-ERB modulators can help treat metabolic disturbances and certain types of cancer.
Assuntos
Neoplasias Ósseas , Transtornos Cronobiológicos , Osteossarcoma , Humanos , Técnicas de Cultura de Células , Osteossarcoma/genética , Isoformas de Proteínas , Receptores Citoplasmáticos e NuclearesRESUMO
Patients who are medically compromised may be at an increased risk of complications and treatment errors following periodontal therapy. A review of the evidence on the topic is presented, in relation to the type of complication reported, of periodontal treatment, and of patients' medical status. Further, a framework for risk assessment and appropriate treatment modifications is introduced, with the aim of facilitating the management of patients with existing comorbidities and reducing the incidence of treatment complications.
Assuntos
Doenças Periodontais , Humanos , Doenças Periodontais/complicações , Assistência Odontológica , Medição de RiscoRESUMO
Angiotensin II (AngII) has potent cardiac hypertrophic effects mediated through activation of hypertrophic signaling like Wnt/ß-Catenin signaling. In the current study, we examined the role of protein arginine methyltransferase 7 (PRMT7) in cardiac function. PRMT7 was greatly decreased in hypertrophic hearts chronically infused with AngII and cardiomyocytes treated with AngII. PRMT7 depletion in rat cardiomyocytes resulted in hypertrophic responses. Consistently, mice lacking PRMT7 exhibited the cardiac hypertrophy and fibrosis. PRMT7 overexpression abrogated the cellular hypertrophy elicited by AngII, while PRMT7 depletion exacerbated the hypertrophic response caused by AngII. Similar with AngII treatment, the cardiac transcriptome analysis of PRMT7-deficient hearts revealed the alteration in gene expression profile related to Wnt signaling pathway. Inhibition of PRMT7 by gene deletion or an inhibitor treatment enhanced the activity of ß-catenin. PRMT7 deficiency decreases symmetric dimethylation of ß-catenin. Mechanistic studies reveal that methylation of arginine residue 93 in ß-catenin decreases the activity of ß-catenin. Taken together, our data suggest that PRMT7 is important for normal cardiac function through suppression of ß-catenin activity.
Assuntos
Cardiomegalia/genética , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Proteína-Arginina N-Metiltransferases/genética , beta Catenina/genética , Angiotensinas , Animais , Cardiomegalia/induzido quimicamente , Cardiomegalia/metabolismo , Fibrose , Perfilação da Expressão Gênica/métodos , Humanos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Miocárdio/patologia , Proteína-Arginina N-Metiltransferases/deficiência , RNA-Seq/métodos , Via de Sinalização Wnt/genética , beta Catenina/metabolismoRESUMO
BACKGROUND: People with disabilities face difficulties in oral health management and gaining access to dental care. The availability of a regular source of dental care (RSDC) is an important factor that influences the access to health services and care management. The purpose of this study was to determine the effect of the availability of RSDC on the number of annual dental visits and dental expenses per visit among people with disabilities. METHODS: Data of 7,896,251 patients with dental problems in South Korea were analyzed using the 2002-2018 National Health Insurance claims data. A generalized estimating equation was applied to analyze the repeated-measurement data, and the interaction effect between RSDC and the disability severity was evaluated. RESULTS: The number of annual dental visits was higher among people with (2.62) than among those without (2.23) disabilities. Despite their increased dental needs, both annual dental visits and dental expenses per visit were low among older individuals (p < 0.001). The proportion and frequency of annual dental visits was lower among women than among men with disabilities. RSDC had differential effects on the severity of disability. Compared to people without disabilities, RSDC increased the number of annual dental visits (p = 0.067) and the dental expenses per visit (p < 0.05) among those with severe disabilities, but the effect on the number of annual dental visits was not significant among those with mild disabilities (p = 0.698). CONCLUSIONS: Our results suggest a need for a special dental care system for people with disabilities, to ensure an RSDC, particularly for women and for older people with disabilities.
Assuntos
Pessoas com Deficiência , Pacientes Ambulatoriais , Masculino , Humanos , Feminino , Idoso , Estudos Retrospectivos , Acessibilidade aos Serviços de Saúde , Assistência OdontológicaRESUMO
Transient receptor potential ankyrin 1 and vanilloid 1 (TRPA1 and TRPV1, respectively) channels contribute to inflammatory and neuropathic pain, indicating that their pharmacological inhibition could be a novel strategy for treating painful diseases. However, the mechanisms of TRPA1/V1 channel modulation have been mostly characterized to be upregulation and sensitization via variety of exogenous stimuli, endogenous inflammatory mediators, and metabolites of oxidative stress. Here we used calcium imaging of dorsal root ganglion neurons to identify an inhibitor signaling pathway for TRPA1 and TRPV1 regulated by resolvins (RvD1 and RvE1), which are endogenous anti-inflammatory lipid mediators. TRPA1 and TRPV1 channel activations were evoked by the TRPA1 agonist allyl isothiocyanate and the TRPV1 agonist capsaicin. Our results show that RvD1-induced selective inhibition of TRPA1 activity was mediated by free fatty acid receptor 4 (FFAR4)-protein kinase C (PKC) signaling. Experiments assessing RvE1-induced TRPV1 inhibition showed that RvE1 actions required both FFAR1 and FFAR4. Combined stimulation of FFAR1/FFAR4 or FFAR1/PKC mimicked TRPV1 inhibition by RvE1, and these effects were blocked by a protein kinase D (PKD) inhibitor, implying that PKD is an effector of the FFAR/PKC signaling axis in RvE1-induced TRPV1 inhibition. Despite selective inhibition of TRPV1 in the nanomolar range of RvE1, higher concentrations of RvE1 also inhibited TRPA1, possibly through PKC. Collectively, our findings reveal FFAR1 and FFAR4 as key signaling pathways mediating the selective targeting of resolvins to regulate TRPA1 and TRPV1, elucidating endogenous analgesic mechanisms that could be exploited as potential therapeutic targets.
Assuntos
Ácidos Graxos não Esterificados , Receptores Acoplados a Proteínas G , Canais de Cátion TRPV , Animais , Ácidos Graxos não Esterificados/metabolismo , Gânglios Espinais/metabolismo , Camundongos , Células Receptoras Sensoriais/metabolismo , Canal de Cátion TRPA1/genética , Canal de Cátion TRPA1/metabolismo , Canais de Cátion TRPV/genética , Canais de Cátion TRPV/metabolismoRESUMO
Recent studies have shown that protein arginine methyltransferase 1 (PRMT1) is highly expressed in the human heart, and loss of PRMT1 contributes to cardiac remodeling in the heart failure. However, the functional importance of PRMT1 in cardiac ion channels remains uncertain. The slow activating delayed rectifier K+ (IKs ) channel is a cardiac K+ channel composed of KCNQ1 and KCNE1 subunits and is a new therapeutic target for treating lethal arrhythmias in many cardiac pathologies, especially heart failure. Here, we demonstrate that PRMT1 is a critical regulator of the IKs channel and cardiac rhythm. In the guinea pig ventricular myocytes, treatment with furamidine, a PRMT1-specific inhibitor, prolonged the action potential duration (APD). We further show that this APD prolongation was attributable to IKs reduction. In HEK293T cells expressing human KCNQ1 and KCNE1, inhibiting PRMT1 via furamidine reduced IKs and concurrently decreased the arginine methylation of KCNQ1, a pore-forming α-subunit. Evidence presented here indicates that furamidine decreased IKs mainly by lowering the affinity of IKs channels for the membrane phospholipid, phosphatidylinositol 4,5-bisphosphate (PIP2 ), which is crucial for pore opening. Finally, applying exogenous PIP2 to cardiomyocytes prevented the furamidine-induced IKs reduction and APD prolongation. Taken together, these results indicate that PRMT1 positively regulated IKs activity through channel-PIP2 interaction, thereby restricting excessive cardiac action potential.
Assuntos
Insuficiência Cardíaca , Canal de Potássio KCNQ1 , Fosfatos de Fosfatidilinositol/metabolismo , Potenciais de Ação , Animais , Cobaias , Células HEK293 , Insuficiência Cardíaca/metabolismo , Humanos , Canal de Potássio KCNQ1/genética , Canal de Potássio KCNQ1/metabolismo , Miócitos Cardíacos/metabolismo , Canais de Potássio de Abertura Dependente da Tensão da Membrana , Proteína-Arginina N-Metiltransferases/genética , Proteína-Arginina N-Metiltransferases/metabolismo , Proteínas Repressoras/metabolismoRESUMO
Viruses have evolved in tandem with the organisms that they infect. Afflictions of the plant and animal kingdoms with viral infections have forced the host organism to evolve new or exploit existing systems to develop the countermeasures needed to offset viral insults. As one example, nonsense-mediated mRNA decay, a cellular quality-control mechanism ensuring the translational fidelity of mRNA transcripts, has been used to restrict virus replication in both plants and animals. In response, viruses have developed a slew of means to disrupt or become insensitive to NMD, providing researchers with potential new reagents that can be used to more fully understand the NMD mechanism.
Assuntos
Interações Hospedeiro-Patógeno , Degradação do RNAm Mediada por Códon sem Sentido , Vírus/metabolismo , Animais , Humanos , Plantas/virologia , Biossíntese de Proteínas , Estabilidade de RNA , RNA Mensageiro/metabolismo , Proteínas Virais/genética , Fenômenos Fisiológicos Virais , Vírus/classificação , Vírus/genética , Vírus/crescimento & desenvolvimentoRESUMO
Staufen1 (STAU1) is an RNA-binding protein (RBP) that interacts with double-stranded RNA structures and has been implicated in regulating different aspects of mRNA metabolism. Previous studies have indicated that STAU1 interacts extensively with RNA structures in coding regions (CDSs) and 3'-untranslated regions (3'UTRs). In particular, duplex structures formed within 3'UTRs by inverted-repeat Alu elements (IRAlus) interact with STAU1 through its double-stranded RNA-binding domains (dsRBDs). Using 3' region extraction and deep sequencing coupled to ribonucleoprotein immunoprecipitation (3'READS + RIP), together with reanalyzing previous STAU1 binding and RNA structure data, we delineate STAU1 interactions transcriptome-wide, including binding differences between alternative polyadenylation (APA) isoforms. Consistent with previous reports, RNA structures are dominant features for STAU1 binding to CDSs and 3'UTRs. Overall, relative to short 3'UTR counterparts, longer 3'UTR isoforms of genes have stronger STAU1 binding, most likely due to a higher frequency of RNA structures, including specific IRAlus sequences. Nevertheless, a sizable fraction of genes express transcripts showing the opposite trend, attributable to AU-rich sequences in their alternative 3'UTRs that may recruit antagonistic RBPs and/or destabilize RNA structures. Using STAU1-knockout cells, we show that strong STAU1 binding to mRNA 3'UTRs generally enhances polysome association. However, IRAlus generally have little impact on STAU1-mediated polysome association despite having strong interactions with the protein. Taken together, our work reveals complex interactions of STAU1 with its cognate RNA substrates. Our data also shed light on distinct post-transcriptional fates for the widespread APA isoforms in mammalian cells.
Assuntos
Proteínas do Citoesqueleto/química , Proteínas do Citoesqueleto/metabolismo , Polirribossomos/metabolismo , RNA Mensageiro/química , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/metabolismo , Regiões 3' não Traduzidas , Processamento Alternativo , Elementos Alu , Proteínas do Citoesqueleto/genética , Perfilação da Expressão Gênica , Técnicas de Inativação de Genes , Células HEK293 , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Imunoprecipitação , Conformação Molecular , Motivos de Ligação ao RNA , Proteínas de Ligação a RNA/genéticaRESUMO
BACKGROUND: Transversus abdominis plane block (TAPB) is commonly used for postoperative pain control after laparoscopic cholecystectomy. However, few studies have analyzed its effect on pulmonary function. The goal of this study was to elucidate the effect of ultrasound-guided bilateral TAPB on pulmonary function preservation and analgesia after laparoscopic cholecystectomy. METHODS: We enrolled 58 patients who underwent laparoscopic cholecystectomy. Among them, 53 were randomized to group T (n = 27) and group C (n = 26). Group T and group C received ultrasound-guided bilateral TAPB with 40 ml of 0.375% ropivacaine and 40 ml of 0.9% normal saline, respectively. Visual analog scale (VAS) scores, patient-controlled analgesia (PCA) consumption, forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), FEV1/FVC, peak expiratory flow rate (PEF), and modified Borg scale scores were measured until 24 h post-surgery. RESULTS: The VAS scores were significantly lower in group T than in group C at 1 and 8 h after the surgery. PCA consumption was significantly lower in group T than in group C at all postoperative time points. FEV1, PEF, and FEV1/FVC were more preserved in group T than in group C at 1 h. Group T had significantly lower modified Borg scale scores than did group C at 1 and 8 h. CONCLUSION: Ultrasound-guided TAPB is effective in pulmonary function preservation and pain control after laparoscopic cholecystectomy. Therefore, it could be a great option for multimodal analgesia, preservation of pulmonary function, prevention of pulmonary complications including atelectasis, and promotion of postoperative recovery after laparoscopic cholecystectomy. CLINICAL REGISTRATION: This study was enrolled in the Clinical Research Information Service (Clinical Research Information Service, KCT0004435, Hwa Yong Shin, 2019-08-19).
Assuntos
Colecistectomia Laparoscópica , Músculos Abdominais/diagnóstico por imagem , Analgesia Controlada pelo Paciente , Benzamidinas , Colecistectomia Laparoscópica/efeitos adversos , Humanos , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/etiologia , Dor Pós-Operatória/prevenção & controle , Estudos Prospectivos , Ropivacaina , Solução Salina/uso terapêutico , Ultrassonografia de IntervençãoRESUMO
BACKGROUND: This study aimed to investigate the effects of orthodontic treatment on cumulative out-of-pocket (OOP) expenditures for up to 8 years and the factors contributing to changes in individual OOP dental expenses. METHODS: The data of adults aged ≥19 years, 218 with experience of orthodontic treatment (OT group) and 654 without experience of orthodontic treatment (non-OT group) were extracted from the Korea Health Panel Survey between 2009 and 2017 using the propensity score matching method. The total personal OOP expenditure for dental care incurred after orthodontic treatment in the OT group and that incurred in the matched non-OT group were calculated. Since dependent variables, cumulative dental expenditures, were continuous with excess zeros, Tweedie compound Poisson linear models were used to explore the influence of orthodontic treatment experience and demographic and socioeconomic factors, including private insurance, on per capita OOP dental expenditures. RESULTS: The OT group had socioeconomic characteristics distinct from those of general dental patients. The Box-Cox transformed per capita OOP expenditures for dental care in the OT group were lower than those in the non-OT group (P < 0.05). When all covariates were held constant, the non-OT group spent 1.4-times more on OOP dental expenditures, but this was not statistically significant (P > 0.1). The data from those with higher incomes revealed the opposite trend (P < 0.05), while the other covariates were not statistically significant. CONCLUSIONS: Orthodontic treatment had no positive or negative effect on future oral care use. This finding is similar to the inconsistent results of previous clinical studies on oral health and orthodontic treatment.