RESUMO
Gemcitabine (GEM) based induction chemotherapy is a standard treatment for locoregionally advanced nasopharyngeal carcinoma (NPC). However, approximately 15â¯% of patients are still resistant to GEM-containing chemotherapy, which leads to treatment failure. Nevertheless, the underlying mechanisms of GEM resistance remain poorly understood. Herein, based on a microarray analysis, we identified 221 dysregulated lncRNAs, of which, DYNLRB2-AS1 was one of the most upregulated lncRNAs in GEM-resistance NPC cell lines. DYNLRB2-AS1 was shown to function as contain an oncogenic lncRNA that promoted NPC GEM resistance, cell proliferation, but inhibited cell apoptosis. Mechanistically, DYNLRB2-AS1 could directly bind to the DHX9 protein and prevent its interaction with the E3 ubiquitin ligase PRPF19, and thus blocking PRPF19-mediated DHX9 degradation, which ultimately facilitated the repair of DNA damage in the presence of GEM. Clinically, higher DYNLRB2-AS1 expression indicated an unfavourable overall survival of NPC patients who received induction chemotherapy. Overall, this study identified the oncogenic lncRNA DYNLRB2-AS1 as an independent prognostic biomarker for patients with locally advanced NPC and as a potential therapeutic target for overcoming GEM chemoresistance in NPC.
Assuntos
RNA Helicases DEAD-box , Desoxicitidina , Gencitabina , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , RNA Longo não Codificante , Animais , Humanos , Antimetabólitos Antineoplásicos/farmacologia , Antimetabólitos Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , RNA Helicases DEAD-box/metabolismo , RNA Helicases DEAD-box/genética , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Desoxicitidina/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Carcinoma Nasofaríngeo/tratamento farmacológico , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/patologia , Carcinoma Nasofaríngeo/metabolismo , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/metabolismo , Proteínas de Neoplasias , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Ubiquitinação/efeitos dos fármacosRESUMO
OBJECTIVE: Rheumatoid arthritis (RA) is a kind of chronic inflammatory disease characterized by the release of inflammatory cytokines and cardiomyocyte apoptosis, which lead to increased riskfor heart diseases. This study aims to explore the possible effect and mechanism of Celastrol on RA induced cardiac impairments in rats. METHODS: Collagen induced RA wistar rat models (CIA) were established for the measurement on secondary foot swelling degree, polyarthritis index score, spleen and thymus index. Pathological morphology was observed using H&E staining. Heart fibrosis was measured after Sirius red staining, while cell apoptosis was determined by TUNEL staining. For in vitro experiments, rat cardiomyocytes were isolated to determine the inflammatory cytokine secretion and cell apoptosis using ELISA and flow cytometry, respectively. Protein expressions of related index and autophagy were detected by Western blot and immunofluorescence. RESULTS: CIA rat model was successfully established and characterized by severe secondary foot swelling degree, and increased polyarthritis index score and spleen and thymus index. Synovial hyperplasia, disordered cardiomyocytes, cell infiltration and fibrosis were also observed in CIA rat model. Compared with CIA model, Celastrol treatment could suppress the release of inflammatory cytokines, including TNF-α, IL-6, IL-1ß, as well as inhibiting the expressions of Bax, cleaved caspase3, collagen I, collagen III and α-SMA. In addition to that, Celastrol treatment can attenuate cell apoptosis and fibrosis of cardiomyocytes and elevate Bcl-2 expression. RA induced cell autophagy can be suppressed by Celastrol through inhibiting the activation of TLR2/HMGB1 signal pathway. CONCLUSION: Celastrol can regulate TLR2/HMGB1 signal pathway to suppress autophagy and therefore exert cardioprotective effect in RA.
Assuntos
Artrite Reumatoide/complicações , Autofagia/efeitos dos fármacos , Cardiotônicos/farmacologia , Proteína HMGB1/metabolismo , Cardiopatias/prevenção & controle , Triterpenos Pentacíclicos/farmacologia , Receptor 2 Toll-Like/metabolismo , Animais , Apoptose/efeitos dos fármacos , Artrite Reumatoide/imunologia , Artrite Reumatoide/metabolismo , Biomarcadores/metabolismo , Western Blotting , Cardiotônicos/uso terapêutico , Citocinas/metabolismo , Ensaio de Imunoadsorção Enzimática , Imunofluorescência , Cardiopatias/etiologia , Cardiopatias/metabolismo , Cardiopatias/patologia , Marcação In Situ das Extremidades Cortadas , Camundongos Endogâmicos DBA , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/imunologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Triterpenos Pentacíclicos/uso terapêutico , Distribuição Aleatória , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacosRESUMO
Hepatitis delta virus (HDV) ribozyme performs the self-cleavage activity through folding to a double pseudoknot structure. The folding of functional RNA structures is often coupled with the transcription process. In this work, we developed a new approach for predicting the cotranscriptional folding kinetics of RNA secondary structures with pseudoknots. We theoretically studied the cotranscriptional folding behavior of the 99-nucleotide (nt) HDV sequence, two upstream flanking sequences, and one downstream flanking sequence. During transcription, the 99-nt HDV can effectively avoid the trap intermediates and quickly fold to the cleavage-active state. It is different from its refolding kinetics, which folds into an intermediate trap state. For all the sequences, the ribozyme regions (from 1 to 73) all fold to the same structure during transcription. However, the existence of the 30-nt upstream flanking sequence can inhibit the ribozyme region folding into the active native state through forming an alternative helix Alt1 with the segments 70-90. The longer upstream flanking sequence of 54 nt itself forms a stable hairpin structure, which sequesters the formation of the Alt1 helix and leads to rapid formation of the cleavage-active structure. Although the 55-nt downstream flanking sequence could invade the already folded active structure during transcription by forming a more stable helix with the ribozyme region, the slow transition rate could keep the structure in the cleavage-active structure to perform the activity.
Assuntos
Vírus Delta da Hepatite/genética , RNA Catalítico/química , RNA Catalítico/genética , Transcrição Gênica , Domínio Catalítico , Vírus Delta da Hepatite/química , Cinética , Modelos Moleculares , Conformação de Ácido Nucleico , Dobramento de RNA , RNA Viral/química , RNA Viral/genéticaRESUMO
MOTIVATION: Comparison of RNA 3D structures can be used to infer functional relationship of RNA molecules. Most of the current RNA structure alignment programs are built on size-dependent scales, which complicate the interpretation of structure and functional relations. Meanwhile, the low speed prevents the programs from being applied to large-scale RNA structural database search. RESULTS: We developed an open-source algorithm, RNA-align, for RNA 3D structure alignment which has the structure similarity scaled by a size-independent and statistically interpretable scoring metric. Large-scale benchmark tests show that RNA-align significantly outperforms other state-of-the-art programs in both alignment accuracy and running speed. The major advantage of RNA-align lies at the quick convergence of the heuristic alignment iterations and the coarse-grained secondary structure assignment, both of which are crucial to the speed and accuracy of RNA structure alignments. AVAILABILITY AND IMPLEMENTATION: https://zhanglab.ccmb.med.umich.edu/RNA-align/. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.
Assuntos
Conformação de Ácido Nucleico , Software , Algoritmos , RNARESUMO
The yjdF riboswitch resides in potential 5' UTRs of homologues of protein-coding gene yjdF in Firmicutes. Unlike other 30 riboswitch classes previously validated, this riboswitch class, can sense and bind to a broad collection of azaaromatic ligands. Among these compounds, some do activate production of yjdF protein driven by the riboswitch, while others are out of riboswitch-mediated modulation possibly because of the toxicity at high ligand concentrations. By incorporating the structures with pseudoknots and ligand binding kinetics into the co-transcriptional folding theory, we theoretically studied the co-transcriptional folding behaviors of the yjdF riboswitch from Bacillus subtilis at different transcription conditions. Like most riboswitches, the yjdF riboswitch can quickly fold into the aptamer structure without any trapped states during the transcription process. After the aptamer structure is formed, the riboswitch shows two main co-transcriptional folding pathways: aptamerâON stateâOFF state and aptamerâ¯ââ¯the ligand bound aptamerâ¯ââ¯the ligand bound ON state. Our results suggested that this translational riboswitch is coupled with the transcription process to exert its biological function and it is kinetically controlled. The threshold concentration for the ligand to activate the riboswitch depends on the transcription rate and the association rate of the ligand binding.
Assuntos
Proteínas de Bactérias/genética , Regulação da Expressão Gênica , Ligantes , Riboswitch/genética , Transcrição Gênica , Aptâmeros de Nucleotídeos , Bacillus subtilis/genética , Firmicutes , Hidrocarbonetos Aromáticos , Cinética , Conformação de Ácido Nucleico , Dobramento de RNARESUMO
Riboswitches, which are located within certain noncoding RNA region perform functions as genetic "switches", regulating when and where genes are expressed in response to certain ligands. Understanding the numerous functions of riboswitches requires computation models to predict structures and structural changes of the aptamer domains. Although aptamers often form a complex structure, computational approaches, such as RNAComposer and Rosetta, have already been applied to model the tertiary (three-dimensional (3D)) structure for several aptamers. As structural changes in aptamers must be achieved within the certain time window for effective regulation, kinetics is another key point for understanding aptamer function in riboswitch-mediated gene regulation. The coarse-grained self-organized polymer (SOP) model using Langevin dynamics simulation has been successfully developed to investigate folding kinetics of aptamers, while their co-transcriptional folding kinetics can be modeled by the helix-based computational method and BarMap approach. Based on the known aptamers, the web server Riboswitch Calculator and other theoretical methods provide a new tool to design synthetic riboswitches. This review will represent an overview of these computational methods for modeling structure and kinetics of riboswitch aptamers and for designing riboswitches.
Assuntos
Aptâmeros de Nucleotídeos/química , Biologia Computacional/métodos , Riboswitch , Cinética , Ligantes , Simulação de Dinâmica Molecular , Conformação de Ácido Nucleico , Biologia Sintética/métodosRESUMO
Riboswitches are genetic control elements within non-coding regions of mRNA. These self-regulatory elements have been found to sense a range of small metabolites, ions, and other physical signals to exert regulatory control of transcription, translation, and splicing. To date, more than a dozen riboswitch classes have been characterized that vary widely in size and secondary structure. Extensive experiments and theoretical studies have made great strides in understanding the general structures, genetic mechanisms, and regulatory activities of individual riboswitches. As the ligand-dependent co-transcriptional folding and unfolding dynamics of riboswitches are the key determinant of gene expression, it is important to investigate the thermodynamics and kinetics of riboswitches both in the presence and absence of metabolites under the transcription. This review will provide a brief summary of the studies about the regulation mechanisms of the pbuE, SMK, yitJ, and metF riboswitches based on the ligand-dependent co-transcriptional folding of the riboswitches.
Assuntos
Dobramento de RNA , RNA Mensageiro/química , Riboswitch/genética , Transcrição Gênica , Regulação da Expressão Gênica , Cinética , Ligantes , Conformação de Ácido Nucleico , RNA Mensageiro/genética , TermodinâmicaRESUMO
The thermodynamic and kinetic parameters of an RNA base pair were obtained through a long-time molecular dynamics simulation of the opening-closing switch process of the base pair near its melting temperature. The thermodynamic parameters were in good agreement with the nearest-neighbor model. The opening rates showed strong temperature dependence, however, the closing rates showed only weak temperature dependence. The transition path time was weakly temperature dependent and was insensitive to the energy barrier. The diffusion constant exhibited super-Arrhenius behavior. The free energy barrier of breaking a single base stack results from the enthalpy increase, ΔH, caused by the disruption of hydrogen bonding and base-stacking interactions. The free energy barrier of base pair closing comes from the unfavorable entropy loss, ΔS, caused by the restriction of torsional angles. These results suggest that a one-dimensional free energy surface is sufficient to accurately describe the dynamics of base pair opening and closing, and the dynamics are Brownian.
Assuntos
Pareamento de Bases , RNA/química , Cinética , Simulação de Dinâmica Molecular , Dobramento de RNA , Termodinâmica , Temperatura de TransiçãoRESUMO
Riboswitches are RNA residue segments located in untranslated regions of messenger RNAs. These folded segments directly bind ligands through shape complementarity and specific interactions in cells and alter the expression of genes at the transcriptional or translational level through conformation change. Using the recently developed systematic helix-based computational method to predict the cotranscription folding kinetics, we theoretically studied the cotranscription folding behavior of the Bacillus subtilis pbuE riboswitch in the absence and presence of the ligand. The ligand concentration, the transcription speed, and the transcription pausing are incorporated into the method. The results are in good agreement with the experimental results. We find that there are no obvious misfolded structures formed during the transcription and the formation of the ligand bound state is rate-limited by the association of the ligand and the RNA. For this kinetically driven riboswitch, the ligand concentration, the transcription speed, and the transcription pausing are coupled to perform regulatory activity.
Assuntos
Bacillus subtilis/genética , RNA Mensageiro/metabolismo , Riboswitch , Termodinâmica , Bacillus subtilis/metabolismo , Cinética , Ligantes , Conformação de Ácido Nucleico , RNA Mensageiro/genética , Riboswitch/genética , Transcrição Gênica/genéticaRESUMO
Riboswitches which function at the transcriptional level are sensitive to cotranscriptional folding. Based on the recently proposed theory of cotranscriptional folding, we developed a transition node approximation method to effectively decrease the conformation space of long RNA chains. Our results indicate that this approximation is reliable for calculating the cotranscriptional folding kinetics of long mRNA chains. We theoretically studied the cotranscriptional folding behavior of the yitJ and metF riboswitches in the absence/presence of S-adenosylmethionine. Although the two S-box riboswitches have similar OFF-state structures and share common features of riboswitches operated at the transcriptional level, their regulation mechanisms are different. The yitJ riboswitch is regulated by a combination of thermodynamic and kinetic mechanisms, while the metF riboswitch is solely kinetically controlled. For the yitJ riboswitch, transcriptional pausing at the U-stretch directly following the terminator decreases the amount of ligand required to trigger the switch. The different regulation mechanisms and binding affinities of the two riboswitches result from the different lengths of the anti-terminator helix, which in yitJ is short and only disrupts helix P1 of the riboswitch aptamer, but in metF is long and breaks both the helices P1 and P4.
Assuntos
Dobramento de RNA , RNA Mensageiro/química , Riboswitch , Termodinâmica , 5,10-Metilenotetra-Hidrofolato Redutase (FADH2)/química , 5,10-Metilenotetra-Hidrofolato Redutase (FADH2)/genética , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Cinética , Modelos Moleculares , Conformação de Ácido Nucleico , RNA Mensageiro/genéticaRESUMO
RNA folding kinetics is directly tied to RNA biological functions. We introduce here a new approach for predicting the folding kinetics of RNA secondary structure with pseudoknots. This approach is based on our previous established helix-based method for predicting the folding kinetics of RNA secondary structure. In this approach, the transition rates for an elementary step: (1) formation, (2) disruption of a helix stem, and (3) helix formation with concomitant partial melting of an incompatible helix, are calculated with the free energy landscape. The folding kinetics of the Hepatitis delta virus (HDV) ribozyme and the mutated sequences are studied with this method. The folding pathways are identified by recursive searching the states with high net flux-in(out) population starting from the native state. The theory results are in good agreement with that of the experiments. The results indicate that the bi-phasic folding kinetics for the wt HDV sequence is ascribed to the kinetic partitioning mechanism: Part of the population will quickly fold to the native state along the fast pathway, while another part of the population will fold along the slow pathway, in which the population is trapped in a non-native state. Single mutation not only changes the folding rate but also the folding pathway.
Assuntos
Vírus Delta da Hepatite/química , RNA Catalítico/química , RNA Viral/química , Sequência de Bases , Hepatite D/virologia , Vírus Delta da Hepatite/genética , Cinética , Mutação , Conformação de Ácido Nucleico , RNA Catalítico/genética , RNA Viral/genética , TermodinâmicaRESUMO
In this paper, a high-quality Cl-doped two-dimensional halide perovskite (PEA)2Pb(Br0.95Cl0.05)4 crystal was prepared using a seed-induced volatile solvent method. On optimizing the Cl- doping concentration, we found that 5% Cl-doping results in (PEA)2PbBr4 with the highest optical and photon yield. Based on the Cl-doped (PEA)2PbBr4 single crystal, the response characterization of the (PEA)2Pb(Br0.95Cl0.05)4 crystal in the mixed field of neutrons and gamma rays (n/γ) has been verified. Using the time-of-flight method and the linear relationship between integral charge and neutron yield, it was proved that (PEA)2Pb(Br0.95Cl0.05)4 crystal can be used for n/γ screening. The time difference between the fast neutron released by a single nuclear reaction and the γ photon arriving at the detector was 130 ns, and the arrival time of the γ photon is earlier than that of the fast neutron. This work has a broad application prospect in the study of nuclear reaction kinetics, the monitoring of the neutron yield of fusion devices and the total energy released by nuclear reactions.
RESUMO
Members of the Metal Tolerance Protein (MTP) family are critical in mediating the transport and tolerance of divalent metal cations. Despite their significance, the understanding of MTP genes in mustard (Brassica juncea) remains limited, especially regarding their response to heavy metal (HM) stress. In our study, we identified MTP gene sets in Brassica rapa (17 genes), Brassica nigra (18 genes), and B. juncea (33 genes) using the HMMER (Cation_efflux; PF01545) and BLAST analysis. For the 33 BjMTPs, a comprehensive bioinformatics analysis covering the physicochemical properties, phylogenetic relationships, conserved motifs, protein structures, collinearity, spatiotemporal RNA-seq expression, GO enrichment, and expression profiling under six HM stresses (Mn2+, Fe2+, Zn2+, Cd2+, Sb3+, and Pb2+) were carried out. According to the findings of physicochemical characteristics, phylogenetic tree, and collinearity, the allopolyploid B. juncea's MTP genes were inherited from its progenitors, B. rapa and B. nigra, with minimal gene loss during polyploidization. Members of the BjMTP family exhibited conserved motifs, promoter elements, and expression patterns across subgroups, consistent with the seven evolutionary branches (G1, G4-G9, and G12) of the MTPs. Further, spatiotemporal expression profiling under HM stresses successfully identified specific genes and crucial cis-regulatory elements associated with the response of BjMTPs to HM stresses. These findings may contribute to the genetic improvement of B. juncea for enhanced HM tolerance, facilitating the remediation of HM-contaminated areas.
Assuntos
Regulação da Expressão Gênica de Plantas , Metais Pesados , Mostardeira , Filogenia , Proteínas de Plantas , Estresse Fisiológico , Mostardeira/genética , Metais Pesados/toxicidade , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estresse Fisiológico/genética , Perfilação da Expressão Gênica , Biologia Computacional/métodosRESUMO
Background: Multiple myeloma (MM), an incurable plasma cell malignancy. The significance of the relationship between natural killer (NK) cell-related genes and clinical factors in MM remains unclear. Methods: Initially, we extracted NK cell-related genes from peripheral blood mononuclear cells (PBMC) of healthy donors and MM samples by employing single-cell transcriptome data analysis in TISCH2. Subsequently, we screened NK cell-related genes with prognostic significance through univariate Cox regression analysis and protein-protein interaction (PPI) network analysis. Following the initial analyses, we developed potential subtypes and prognostic models for MM using consensus clustering and lasso regression analysis. Additionally, we conducted a correlation analysis to explore the relationship between clinical features and risk scores. Finally, we constructed a weighted gene co-expression network analysis (WGCNA) and identified differentially expressed genes (DEGs) within the MM cohort. Results: We discovered that 153 NK cell-related genes were significantly associated with the prognosisof MM patients (P <0.05). Patients in NK cluster A exhibited poorer survival outcomes compared to those in cluster B. Furthermore, our NK cell-related genes risk model revealed that patients with a high risk score had significantly worse prognoses (P <0.05). Patients with a high risk score were more likely to exhibit adverse clinical markers. Additionally, the nomogram based on NK cell-related genes demonstrated strong prognostic performance. The enrichment analysis indicated that immune-related pathways were significantly correlated with both the NK subtypes and the NK cell-related genes risk model. Ultimately, through the combined use of WGCNA and DEGs analysis, and by employing Venn diagrams, we determined that ITM2C is an independent prognostic marker for MM patients. Conclusion: In this study, we developed a novel model based on NK cell-related genes to stratify the prognosis of MM patients. Notably, higher expression levels of ITM2C were associated with more favorable survival outcomes in these patients.
RESUMO
Despite docetaxel combined with cisplatin and 5-fluorouracil (TPF) being the established treatment for advanced nasopharyngeal carcinoma (NPC), there are patients who do not respond positively to this form of therapy. However, the mechanisms underlying this lack of benefit remain unclear. DCAF7 is identified as a chemoresistance gene attenuating the response to TPF therapy in NPC patients. DCAF7 promotes the cisplatin resistance and metastasis of NPC cells in vitro and in vivo. Mechanistically, DCAF7 serves as a scaffold protein that facilitates the interaction between USP10 and G3BP1, leading to the elimination of K48-linked ubiquitin moieties from Lys76 of G3BP1. This process helps prevent the degradation of G3BP1 via the ubiquitinâproteasome pathway and promotes the formation of stress granule (SG)-like structures. Moreover, knockdown of G3BP1 successfully reversed the formation of SG-like structures and the oncogenic effects of DCAF7. Significantly, NPC patients with increased levels of DCAF7 showed a high risk of metastasis, and elevated DCAF7 levels are linked to an unfavorable prognosis. The study reveals DCAF7 as a crucial gene for cisplatin resistance and offers further understanding of how chemoresistance develops in NPC. The DCAF7-USP10-G3BP1 axis contains potential targets and biomarkers for NPC treatment.
RESUMO
The dysregulation of long non-coding RNAs (lncRNAs) are involved in regulating tumor progression in multiple manner. However, little is known about whether lncRNA is involved in the translation regulation of proteins. Here, we identified that the suppressor of inflammatory macrophage apoptosis lncRNA (SIMALR) was highly expressed in nasopharyngeal carcinoma (NPC) tissues by analyzing the lncRNA microarray. Clinically, the high expression of SIMALR served as an independent predictor for inferior prognosis in NPC patients. SIMALR functioned as an oncogenic lncRNA that promoted the proliferation and metastasis of NPC cells in vitro and in vivo. Mechanistically, SIMALR served as a critical accelerator of protein synthesis by binding to eEF1A2 (eukaryotic translation elongation factor 1 alpha 2), one of the most crucial regulators in the translation machinery of the eukaryotic cells, and enhancing its endogenous GTPase activity. Furthermore, SIMALR mediated the activation of eEF1A2 phosphorylation to accelerate the translation of ITGB4/ITGA6, ultimately promoting the malignant phenotype of NPC cells. In addition, N-acetyltransferase 10 (NAT10) enhanced the stability of SIMALR and caused its overexpression in NPC through the N4-acetylcytidine (ac4C) modification. In sum, our results illustrate SIMALR functions as an accelerator for protein translation and highlight the oncogenic role of NAT10-SIMALR-eEF1A2-ITGB4/6 axis in NPC.
RESUMO
Chemoresistance is a main reason for treatment failure in patients with nasopharyngeal carcinoma, but the exact regulatory mechanism underlying chemoresistance in nasopharyngeal carcinoma remains to be elucidated. Here, we identify PJA1 as a key E3 ubiquitin ligase involved in nasopharyngeal carcinoma chemoresistance that is highly expressed in nasopharyngeal carcinoma patients with nonresponse to docetaxel-cisplatin-5-fluorouracil induction chemotherapy. We find that PJA1 facilitates docetaxel resistance by inhibiting GSDME-mediated pyroptosis in nasopharyngeal carcinoma cells. Mechanistically, PJA1 promotes the degradation of the mitochondrial protein PGAM5 by increasing its K48-linked ubiquitination at K88, which further facilitates DRP1 phosphorylation at S637 and reduced mitochondrial reactive oxygen species production, resulting in suppression of GSDME-mediated pyroptosis and the antitumour immune response. PGAM5 knockdown fully restores the docetaxel sensitization effect of PJA1 knockdown. Moreover, pharmacological targeting of PJA1 with the small molecule inhibitor RTA402 enhances the docetaxel sensitivity of nasopharyngeal carcinoma in vitro and in vivo. Clinically, high PJA1 expression indicates inferior survival and poor clinical efficacy of TPF IC in nasopharyngeal carcinoma patients. Our study emphasizes the essential role of E3 ligases in regulating chemoresistance and provides therapeutic strategies for nasopharyngeal carcinoma based on targeting the ubiquitin-proteasome system.
Assuntos
Docetaxel , Resistencia a Medicamentos Antineoplásicos , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Piroptose , Ubiquitina-Proteína Ligases , Ubiquitinação , Animais , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Docetaxel/farmacologia , Docetaxel/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Dinaminas/metabolismo , Dinaminas/genética , Fluoruracila/farmacologia , Fluoruracila/uso terapêutico , Gasderminas , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Camundongos Nus , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Proteínas Mitocondriais/metabolismo , Proteínas Mitocondriais/genética , Carcinoma Nasofaríngeo/tratamento farmacológico , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/metabolismo , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/metabolismo , Neoplasias Nasofaríngeas/patologia , Fosfoproteínas Fosfatases/metabolismo , Fosfoproteínas Fosfatases/genética , Fosforilação/efeitos dos fármacos , Piroptose/efeitos dos fármacos , Piroptose/genética , Espécies Reativas de Oxigênio/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitinação/efeitos dos fármacos , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Despite that the docectaxel-cisplatin-5-fluorouracil (TPF) induction chemotherapy has greatly improved patients' survival and became the first-line treatment for advanced nasopharyngeal carcinoma (NPC), not all patients could benefit from this therapy. The mechanism underlying the TPF chemoresistance remains unclear. Here, by analyzing gene-expression microarray data and survival of patients who received TPF chemotherapy, we identify transcription factor ATMIN as a chemoresistance gene in response to TPF chemotherapy in NPC. Mass spectrometry and Co-IP assays reveal that USP10 deubiquitinates and stabilizes ATMIN protein, resulting the high-ATMIN expression in NPC. Knockdown of ATMIN suppresses the cell proliferation and facilitates the docetaxel-sensitivity of NPC cells both in vitro and in vivo, while overexpression of ATMIN exerts the opposite effect. Mechanistically, ChIP-seq combined with RNA-seq analysis suggests that ATMIN is associated with the cell death signaling and identifies ten candidate target genes of ATMIN. We further confirm that ATMIN transcriptionally activates the downstream target gene LCK and stabilizes it to facilitate cell proliferation and docetaxel resistance. Taken together, our findings broaden the insight into the molecular mechanism of chemoresistance in NPC, and the USP10-ATMIN-LCK axis provides potential therapeutic targets for the management of NPC.
Assuntos
Neoplasias Nasofaríngeas , Humanos , Carcinoma Nasofaríngeo/patologia , Docetaxel/uso terapêutico , Neoplasias Nasofaríngeas/patologia , Fatores de Transcrição/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Fluoruracila/uso terapêutico , Quimiorradioterapia/métodos , Cisplatino/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ubiquitina TiolesteraseRESUMO
INTRODUCTION: Cervical squamous cell carcinoma (CESC) is the most common gynecological malignancy worldwide. Although the cancer susceptibility 18 (CASC18) gene was involved in the regulation of cancer biology, its specific role in CESC is not well characterized. METHODS: CASC18-related axis was predicted by bioinformatic analyses, and the competing endogenous RNA (ceRNA) interaction was further validated using quantitative real-time PCR, western blotting, RNA pulldown, and luciferase reporter assays. Transwell and wound healing assays were performed to verify the effect of CASC18 on SiHa and HeLa cell motility. RESULTS: We found that CASC18 was upregulated in CESC tissues. Moreover, interference with CASC18 attenuated NUAK1-mediated epithelial-mesenchymal transition (EMT) and thus suppressed cancer cell motility. Furthermore, the effects of CASC18 knockdown on CESC cells were partly rescued by transfection with the miR-5586-5p inhibitor. Additionally, our findings indicated that CASC18 acts as a ceRNA to enhance NUAK1 expression by sponging miR-5586-5p. CONCLUSION: Our study showed a novel CASC18/miR-5586-5p/NUAK1 ceRNA axis that could regulate cell invasion and migration by modulating EMT in CESC. These findings suggest that CASC18 may potentially serve as a novel therapeutic target in CESC treatment.
Assuntos
Carcinoma de Células Escamosas , MicroRNAs , Neoplasias do Colo do Útero , Feminino , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias do Colo do Útero/genética , Células HeLa , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Invasividade Neoplásica/genética , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica/genética , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Proteínas Repressoras/metabolismoRESUMO
INTRODUCTION: Paediatric AML patients with hyperleukocytosis have a poor prognosis and higher early mortality. Therefore, more studies are needed to explore relevant prognostic indicators and develop effective prevention strategies for this type of childhood AML. METHODS: All original data were obtained from the TARGET database. First, we explored meaningful differentially expressed genes (DEGs) between the hyperleukocytosis group and the non-hyperleukocytosis group. Next, we screened and identified valuable target genes using univariate Cox regression, Cytoscape software, and Kaplan-Meier survival curves. Finally, the coexpressed genes, functional networks, and immune-related activities associated with the target gene were deeply analysed by the GeneMANIA, LinkedOmics, GEPIA2021, TISIDB, and GSCA databases. RESULTS: We selected 1229 DEGs between the hyperleukocytosis group and the non-hyperleukocytosis group in paediatric AML patients. Among them, 495 DEGs were significantly linked with the overall survival of paediatric AML patients. Further, we discovered that CX3CR1 was a promising target gene. Meanwhile, we identified CX3CR1 as an independent prognostic predictor. Besides, we showed that CX3CR1 had strong physical interactions with CX3CL1. Additionally, functional network analysis suggested that CX3CR1 and its coexpressed genes modulated immune response pathways. Subsequent analysis found that immune cells with a high median value of CX3CR1 were monocytes, resting NK cells and CD8 T cells. Finally, we observed that CX3CR1 expression correlated with infiltrating levels of immune cells and immune signatures. CONCLUSION: Elevated CX3CR1 expression may be an adverse prognostic indicator in paediatric AML patients undergoing hyperleukocytosis. Moreover, CX3CR1 may serve as an immunotherapeutic target for AML with hyperleukocytosis in children.