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Inflammatory bowel disease (IBD) is characterized by dysbiosis of the gut microbiota and dysfunction of intestinal stem cells (ISCs). However, the direct interactions between IBD microbial factors and ISCs are undescribed. Here, we identify α2A-adrenergic receptor (ADRA2A) as a highly expressed GPCR in ISCs. Through PRESTO-Tango screening, we demonstrate that tyramine, primarily produced by Enterococcus via tyrosine decarboxylase (tyrDC), serves as a microbial ligand for ADRA2A. Using an engineered tyrDC-deficient Enterococcus faecalis strain and intestinal epithelial cell-specific Adra2a knockout mice, we show that Enterococcus-derived tyramine suppresses ISC proliferation, thereby impairing epithelial regeneration and exacerbating DSS-induced colitis through ADRA2A. Importantly, blocking the axis with an ADRA2A antagonist, yohimbine, disrupts tyramine-mediated suppression on ISCs and alleviates colitis. Our findings highlight a microbial ligand-GPCR pair in ISCs, revealing a causal link between microbial regulation of ISCs and colitis exacerbation and yielding a targeted therapeutic approach to restore ISC function in colitis.
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Colitis , Ratones Noqueados , Receptores Adrenérgicos alfa 2 , Células Madre , Tiramina , Animales , Tiramina/metabolismo , Tiramina/farmacología , Colitis/microbiología , Colitis/inducido químicamente , Colitis/metabolismo , Ratones , Receptores Adrenérgicos alfa 2/metabolismo , Células Madre/metabolismo , Humanos , Ratones Endogámicos C57BL , Tirosina Descarboxilasa/metabolismo , Enterococcus faecalis/metabolismo , Microbioma Gastrointestinal , Mucosa Intestinal/microbiología , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Yohimbina/farmacología , Modelos Animales de Enfermedad , Enterococcus/metabolismo , Intestinos/microbiología , Intestinos/patología , Proliferación Celular , Enfermedades Inflamatorias del Intestino/microbiología , Enfermedades Inflamatorias del Intestino/metabolismo , Sulfato de DextranRESUMEN
Purpose: Intestinal metaplasia plays a crucial role in the risk stratification of gastric cancer development. The objective of the study was to develop a prediction model for Operative Link on Gastric Intestinal Metaplasia (OLGIM) Stage III-IV. Methods: We analyzed 7945 high-risk gastric cancer individuals from 115 hospitals who underwent questionnaires and gastroscope. The participants were assigned to either the development or validation cohort randomly. Demographics and clinical characteristics were obtained. The outcome measurement was OLGIM III-IV. Univariate logistic regression was used for feature selection and multivariate logistic analysis was performed to develop the nomogram. Area under the curves, calibration plots, decision curve and clinical impact analysis were used to assess the performance of the nomogram. Results: 4600 individuals and 3345 individuals were included in the development and validation cohort, of which 124 and 86 individuals were diagnosed with OLGIM III-IV, respectively. Parameters in the training validation cohort matched well and there was no significant difference between two cohorts. A nomogram model for predicting OLGIM Stage III-IV consisted of 4 significantly associated variables, including age, gender, PG I and G-17 (AUC 0.723 and 0.700 for the 2 cohorts). The nomogram demonstrated excellent performance in the calibration curve. Decision curve and clinical impact analysis suggested clinical benefit of the prediction model. Conclusions: This reliable individualized nomogram might contribute to more accurate management for patients with OLGIM III-IV. Therefore, we suggest that this study be used as an incentive to promote the application.
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Cumulative evidence indicates the important role of Nur77 in organ fibrogenesis. However, the role of Nur77 in hepatitis B virus (HBV)-related liver fibrosis (LF) remains unclear. Cells were transfected with the microRNA mimic miRNA-506-3p or inhibitor, and pcDNA3.1-Nur77 or Nur77 guide RNA. Exosomes were isolated from HBV-infected HepG2-sodium taurocholate cotransporting polypeptide cells. The levels of miR-506-3p, Nur77, and LF-related genes and proteins were detected by quantitative polymerase chain reaction (qPCR) and western blot analysis, respectively. The pathology of the liver from HBV-infected patients was examined using hematoxylin-eosin and Masson's staining. The expression of Nur77 in liver tissue was determined by immunohistochemistry, and the LF score was assessed using the METAVIR system. The relationship between miR-506-3p/Nur77 and LF score was analyzed by correlation analysis. HBV infection downregulated miR-506-3p expression and upregulated Nur77 levels in hepatocytes. Exosomes from HBV-infected hepatocytes also displayed decreased gene expression of miR-506-3p and increased expressions of Nur77- and LF-related genes in stellate cells compared with exosomes from hepatocytes with mock infection. These changes were reversed by Nur77 guide RNA. Nur77 expression in liver tissue was strongly correlated with LF, whereas serum miR-506-3p was strongly negatively correlated with LF. Exosomes from HBV-infected hepatocytes activate stellate cells and aggravate LF through the miR-506-3p/Nur77 pathway. These exosomes may be the basis of a promising therapeutic strategy.
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Redox metabolites have been observed to fluctuate through the cell cycle in cancer cells, but the functional impacts of such metabolic oscillations remain unknown. Here, we uncover a mitosis-specific nicotinamide adenine dinucleotide phosphate (NADPH) upsurge that is essential for tumour progression. Specifically, NADPH is produced by glucose 6-phosphate dehydrogenase (G6PD) upon mitotic entry, which neutralizes elevated reactive oxygen species (ROS) and prevents ROS-mediated inactivation of mitotic kinases and chromosome missegregation. Mitotic activation of G6PD depends on the phosphorylation of its co-chaperone protein BAG3 at threonine 285, which results in dissociation of inhibitory BAG3. Blocking BAG3T285 phosphorylation induces tumour suppression. A mitotic NADPH upsurge is present in aneuploid cancer cells with high levels of ROS, while nearly unobservable in near-diploid cancer cells. High BAG3T285 phosphorylation is associated with worse prognosis in a cohort of patients with microsatellite-stable colorectal cancer. Our study reveals that aneuploid cancer cells with high levels of ROS depend on a G6PD-mediated NADPH upsurge in mitosis to protect them from ROS-induced chromosome missegregation.
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Segregación Cromosómica , Neoplasias , Humanos , NADP/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Aneuploidia , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Reguladoras de la Apoptosis/metabolismoRESUMEN
Inflammatory bowel diseases (IBD) are known to have complex, genetically influenced etiologies, involving dysfunctional interactions between the intestinal immune system and the microbiome. Here, we characterized how the RNA transcript from an IBD-associated long non-coding RNA locus ("CARINH-Colitis Associated IRF1 antisense Regulator of Intestinal Homeostasis") protects against IBD. We show that CARINH and its neighboring gene coding for the transcription factor IRF1 together form a feedforward loop in host myeloid cells. The loop activation is sustained by microbial factors, and functions to maintain the intestinal host-commensal homeostasis via the induction of the anti-inflammatory factor IL-18BP and anti-microbial factors called guanylate-binding proteins (GBPs). Extending these mechanistic insights back to humans, we demonstrate that the function of the CARINH/IRF1 loop is conserved between mice and humans. Genetically, the T allele of rs2188962, the most probable causal variant of IBD within the CARINH locus from the human genetics study, impairs the inducible expression of the CARINH/IRF1 loop and thus increases genetic predisposition to IBD. Our study thus illustrates how an IBD-associated lncRNA maintains intestinal homeostasis and protects the host against colitis.
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Colitis , Enfermedades Inflamatorias del Intestino , ARN Largo no Codificante , Humanos , Animales , Ratones , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Enfermedades Inflamatorias del Intestino/genética , Enfermedades Inflamatorias del Intestino/metabolismo , Intestinos , Colitis/metabolismo , Mucosa Intestinal/metabolismoRESUMEN
Objective: This study aimed to explore the clinical characteristics and differential diagnosis of patients with autoimmune pancreatitis (AIP) and pancreatic cancer to prevent misdiagnosis and mistreatment. Methods: The clinical data of patients with AIP with suspected pancreatic or bile duct malignancy and pancreatic cancer were retrospectively analyzed. The risk factors and the diagnostic value of IgG4 and Tbil levels before treatment for AIP was investigated. Moreover, the imaging features and response to hormone therapy were analyzed. Results: AIP was commonly observed in men. Compared to patients with pancreatic cancer, the incidence of poor appetite and weight loss and carbohydrate antigen 19-9 (CA19-9) level was lower in patients with AIP, while the immunoglobulin G4 (IgG4) level was higher (p < 0.05). After treatment, the IgG4 and CA19-9 levels in patients with AIP were decreased (p < 0.001). IgG4 level before treatment (OR = 2.452, 95%CI: 1.180-5.096, P = 0.016) and total bilirubin (Tbil) level before treatment (OR = 0.992, 95%CI: 0.985-0.998, P = 0.013) were independent risk factors of AIP. Furthermore, the diagnostic value of IgG4 level before treatment, Tbil level before treatment, IgG4/Tbil before treatment, and a combination of these indicators was high. Moreover, 15 (68.18%) patients with AIP had space-occupying lesions of the pancreas, and 16 (72.73%) had autoimmune cholangitis. Most patients with AIP were sensitive to hormone therapy. Conclusions: The Tbil and IgG4 levels, imaging findings, and hormone therapy reactivity could differentiate AIP from pancreatic cancer. A combination of IgG4, Tbil, and IgG4/Tbil before treatment might be a promising diagnostic biomarker for AIP.
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Purpose: Helicobacter pylori (H. pylori) infection is a high-risk factor for gastric cancer (GC). The main aim of this study was to evaluate the effect of H. pylori on gastritis staging systems and the value of H. pylori combined with gastritis staging systems in predicting GC risk. Patients and Methods: This study enrolled 609 patients with gastric atrophy (GA) and 527 patients with gastric intestinal metaplasia (GIM), who were graded by the OLGA and OLGIM staging systems, respectively. Each individual underwent serum pepsinogen (PG) test, H. pylori detection and questionnaire investigation. We did a real-world retrospective follow-up survey for them in April 2022. Results: Compared with H. pylori-negative patients, H. pylori-positive patients had higher serum PGs/gastrin-17 (G-17) levels and lower PGR levels, regardless of OLGA/OLGIM stages I-II or III-IV. Furthermore, eight patients with atrophic gastritis who progressed to GC were previously in OLGA stages III-IV and OLGIM stages II-IV. The average duration of this process was 2.19±1.03 years. Logistic regression analysis indicated that PGI and H. pylori infection were independent risk factors of individuals with OLGA stages III-IV. Age and PGR were independent risk factors of patients with OLGIM stages III-IV. PGI and PGR had good clinical diagnostic values for OLGA stages III-IV and OLGIM stages III-IV, respectively. Conclusion: Patients with OLGA/OLGIM stages III-IV should undergo endoscopic surveillance regardless of H. pylori infection. H. pylori-positive patients with OLGIM stage II also have a high risk of GC. H. pylori combined with PGI and PGR is helpful to evaluate the severity of chronic gastritis.
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Background: Endoscopic submucosal dissection (ESD) has been a preferred treatment option for superficial esophageal squamous cell carcinoma (SESCC). Objectives: To compare the outcomes of ESD and esophagectomy in the treatment of SESCC, especially for lesions invading muscularis mucosa or submucosa (pT1a-MM/T1b). Design: We retrospectively analyzed data from patients with SESCC who underwent ESD or esophagectomy between 2015 and 2021. Methods: After propensity score matching, overall survival (OS), disease-specific survival (DSS), recurrence-free survival (RFS), and treatment-related events were compared between the ESD and esophagectomy groups. Furthermore, we performed a Cox regression analysis to identify factors associated with survival. Results: OS and DSS were significantly higher in the ESD group (n = 508) than that in the esophagectomy group (n = 466). After matching, 404 patients (202 per group) were included in the study. No significant differences were found between the ESD and esophagectomy groups in OS (p = 0.566), RFS (p = 0.586), and DSS (p = 0.912). The ESD group showed less blood loss, shorter procedure duration and hospital stay, lower hospital cost, and fewer adverse events. However, a lower R0 resection rate was observed in the ESD group compared to the esophagectomy group. Subgroup analysis showed comparable survival outcomes between the two groups. In Cox regression analysis, age was the independent factor associated with OS. Conclusion: In the treatment of SESCC, ESD showed sufficient safety and advantages. Even for pT1a-MM/pT1b SESCC, ESD may be an alternative treatment to esophagectomy.
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Metabolic rewiring is essential for Th17 cells' functional identity to sense and interpret environmental cues. However, the environmental metabolic checkpoints with specific regulation of Th17 cells, manifesting potential therapeutic opportunities to autoimmune diseases, remain largely unknown. Here, by screening more than one hundred compounds derived from intestinal microbes or diet, we found that vitamin B5 (VB5) restrains Th17 cell differentiation as well as related autoimmune diseases such as experimental autoimmune encephalomyelitis and colitis. Mechanistically, VB5 is catabolized into coenzyme A (CoA) in a pantothenate kinase (PANK)-dependent manner, and in turn, CoA binds to pyruvate kinase isoform 2 (PKM2) to impede its phosphorylation and nuclear translocation, thus inhibiting glycolysis and STAT3 phosphorylation. In humans, reduced serum VB5 levels are found in both IBD and MS patients. Collectively, our study demonstrates a role of VB5 in Th17 cell metabolic reprograming, thus providing a potential therapeutic intervention for Th17 cell-associated autoimmune diseases.
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Encefalomielitis Autoinmune Experimental , Piruvato Quinasa , Humanos , Animales , Ácido Pantoténico , Células Th17 , Isoformas de Proteínas , Coenzima ARESUMEN
Intervertebral disc degeneration (IDD) is a high incidence disease of musculoskeletal system that often leads to stenosis, instability, pain and even deformity of the spinal segments. IDD is an important cause of discogenic lower back pain and often leads to large economic burden to families and society. Currently, the treatment of IDD is aimed at alleviating symptoms rather than blocking or reversing pathological progression of the damaged intervertebral disc. Resveratrol (RSV) is a polyphenol phytoalexin first extracted from the Veratrum grandiflflorum O. Loes and can be found in various plants and red wine. Owing to the in-depth study of pharmacological mechanisms, the therapeutic potential of RSV in various diseases such as osteoarthritis, neurodegenerative diseases, cardiovascular diseases and diabetes have attracted the attention of many researchers. RSV has anti-apoptotic, anti-senescent, anti-inflammatory, anti-oxidative, and anabolic activities, which can prevent further degeneration of intervertebral disc cells and enhance their regeneration. With high safety and various biological functions, RSV might be a promising candidate for the treatment of IDD. This review summarizes the biological functions of RSV in the treatment of IDD and to facilitate further research.
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Degeneración del Disco Intervertebral , Humanos , Degeneración del Disco Intervertebral/tratamiento farmacológico , Resveratrol/farmacología , Resveratrol/uso terapéuticoRESUMEN
Cancer cells have distinctive demands for intermediates from glucose metabolism for biosynthesis and energy in different cell cycle phases. However, how cell cycle regulators and glycolytic enzymes coordinate to orchestrate the essential metabolic processes are still poorly characterized. Here, we report a novel interaction between the mitotic kinase, Aurora A, and the glycolytic enzyme, pyruvate kinase M2 (PKM2), in the interphase of the cell cycle. We found Aurora A-mediated phosphorylation of PKM2 at threonine 45. This phosphorylation significantly attenuated PKM2 enzymatic activity by reducing its tetramerization and also promoted glycolytic flux and the branching anabolic pathways. Replacing the endogenous PKM2 with a nonphosphorylated PKM2 T45A mutant inhibited glycolysis, glycolytic branching pathways, and tumor growth in both in vitro and in vivo models. Together, our study revealed a new protumor function of Aurora A through modulating a rate-limiting glycolytic enzyme, PKM2, mainly during the S phase of the cell cycle. Our findings also showed that although both Aurora A and Aurora B kinase phosphorylate PKM2 at the same residue, the spatial and temporal regulations of the specific kinase and PKM2 interaction are context dependent, indicating intricate interconnectivity between cell cycle and glycolytic regulators.
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Leucemia Mieloide Aguda , Piruvato Quinasa , Humanos , Piruvato Quinasa/metabolismo , Fosforilación , Ácido Pirúvico/metabolismo , Línea Celular Tumoral , Glucólisis , División CelularRESUMEN
BACKGROUND: Gastric microbial dysbiosis were reported to be associated with gastric cancer (GC). This study aimed to explore the variation, diversity, and composition patterns of gastric bacteria in stages of gastric carcinogenesis based on the published datasets. METHODS: We conducted a gastric microbial analysis using 10 public datasets based on 16S rRNA sequencing, including 1270 gastric biopsies of 109 health control, 183 superficial gastritis (SG), 135 atrophic gastritis (AG), 124 intestinal metaplasia (IM), 94 intraepithelial neoplasia (IN), 344 GC, and 281 adjacent normal tissues. And QIIME2-pipeline, DESeq2, NetMoss2, vegan, igraph, and RandomForest were used for the data processing and analysis. RESULTS: We identified three gastric microbial communities among all the gastric tissues. The first community (designate as GT-H) was featured by the high abundance of Helicobacter. The other two microbial communities, namely GT-F, and GT-P, were featured by the enrichment of phylum Firmicutes and Proteobacteria, respectively. The distribution of GC-associated bacteria, such as Fusobacterium, Peptostreptococcus, Streptococcus, and Veillonella were enriched in tumor tissues, and mainly distributed in GT-F type microbial communities. Compared with SG, AG, and IM, the bacterial diversity in GC was significantly reduced. And the strength of microbial interaction networks was initially increased in IM but gradually decreased from IN to GC. In addition, Randomforest models constructed in in GT-H and GT-F microbial communities showed excellent performance in distinguishing GC from SG and precancerous stages, with varied donated bacteria. CONCLUSIONS: This study identified three types of gastric microbiome with different patterns of composition which helps to clarify the potential key bacteria in the development of gastric carcinogenesis.
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Gastritis Atrófica , Gastritis , Microbioma Gastrointestinal , Infecciones por Helicobacter , Helicobacter pylori , Microbiota , Neoplasias Gástricas , Bacterias/genética , Carcinogénesis/patología , Mucosa Gástrica/microbiología , Gastritis/complicaciones , Gastritis/microbiología , Gastritis/patología , Gastritis Atrófica/complicaciones , Gastritis Atrófica/patología , Microbioma Gastrointestinal/genética , Infecciones por Helicobacter/microbiología , Helicobacter pylori/genética , Humanos , Metaplasia , ARN Ribosómico 16S/genéticaRESUMEN
Background: Endoscopic submucosal dissection (ESD) has become a preferred treatment option for early gastric cancer (EGC). This study aimed to compare the clinical outcomes of ESD and surgical resection for EGC. Methods: This was a retrospective case-control study. Patients with a diagnosis of EGC who underwent ESD or surgery in our hospital from 2011 to 2020 were enrolled. We compared the clinical characteristics and treatment outcomes of these two groups according to propensity score-matching. The primary outcome comparison was overall survival (OS). Secondary outcomes were disease-specific survival (DSS), recurrence-free survival (RFS), and treatment-related events. Results: In the matched cohort, the ESD group showed comparable OS, RFS, and DSS with the surgery group. Statistical differences were shown in blood loss and adverse events. Furthermore, the ESD group showed lower hospital cost, as well as a shorter operative time and hospital duration than the surgery group. The R0 resection and recurrence rates were similar between the two groups. In Cox regression analysis, age, tumor size, poor differentiation, and lymphovascular invasion were regarded as independent factors of OS. Conclusions: With sufficient safety and advantages, ESD can be a first-line treatment of EGC. Preoperative evaluation is vital to the appropriate treatment and prognosis.
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Liver failure is characterized by serious liver decompensation and high mortality. The activation of systemic immune responses and systemic inflammation are widely accepted as the core pathogenesis of liver failure. Glucocorticoids (GCs) are most regularly utilized to suppress excessive inflammatory reactions and immunological responses. GCs have been used in the clinical treatment of liver failure for nearly 60 years. While there has been no unanimity on the feasibility and application of GC treatment in liver failure until recently. The most recent trials have produced conflicting results when it comes to the dose and time for GC therapy of different etiology of liver failure. Our review outlines the issues and options in managing GC treatment in liver failure based on an investigation of the molecular mechanism that GC may give in the treatment.
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Glucocorticoides , Fallo Hepático , Glucocorticoides/uso terapéutico , Humanos , Inmunidad , Inmunoterapia/efectos adversos , Inflamación/patología , Fallo Hepático/tratamiento farmacológico , Fallo Hepático/etiologíaRESUMEN
N6-methyladenosine (m6A) is an abundant mRNA modification and affects many biological processes. However, how m6A levels are regulated during physiological or pathological processes such as virus infections, and the in vivo function of m6A in the intestinal immune defense against virus infections are largely unknown. Here, we uncover a novel antiviral function of m6A modification during rotavirus (RV) infection in small bowel intestinal epithelial cells (IECs). We found that rotavirus infection induced global m6A modifications on mRNA transcripts by down-regulating the m6a eraser ALKBH5. Mice lacking the m6A writer enzymes METTL3 in IECs (Mettl3ΔIEC) were resistant to RV infection and showed increased expression of interferons (IFNs) and IFN-stimulated genes (ISGs). Using RNA-sequencing and m6A RNA immuno-precipitation (RIP)-sequencing, we identified IRF7, a master regulator of IFN responses, as one of the primary m6A targets during virus infection. In the absence of METTL3, IECs showed increased Irf7 mRNA stability and enhanced type I and III IFN expression. Deficiency in IRF7 attenuated the elevated expression of IFNs and ISGs and restored susceptibility to RV infection in Mettl3ΔIEC mice. Moreover, the global m6A modification on mRNA transcripts declined with age in mice, with a significant drop from 2 weeks to 3 weeks post birth, which likely has broad implications for the development of intestinal immune system against enteric viruses early in life. Collectively, we demonstrated a novel host m6A-IRF7-IFN antiviral signaling cascade that restricts rotavirus infection in vivo.
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Intestinos/inmunología , Infecciones por Rotavirus/inmunología , Rotavirus/clasificación , Desmetilasa de ARN, Homólogo 5 de AlkB/genética , Desmetilasa de ARN, Homólogo 5 de AlkB/metabolismo , Animales , Línea Celular , Pruebas Genéticas , Humanos , Factor 7 Regulador del Interferón/genética , Factor 7 Regulador del Interferón/metabolismo , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Metiltransferasas/genética , Metiltransferasas/metabolismo , Ratones , Ratones Endogámicos , Ratones Noqueados , Proteínas de Microfilamentos/genética , Proteínas de Microfilamentos/metabolismo , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Carga ViralRESUMEN
BACKGROUND: Metabolic reprogramming and redox homeostasis contribute to esophageal squamous cell carcinoma (ESCC). CDC-like kinase 4 (CLK4) is a dual-specificity kinase that can phosphorylate substrates' tyrosine or serine/threonine residue. However, the role and mechanism of CLK4 in ESCC remain unknown. METHODS: CLK4 expression was analysed using publicly available datasets and confirmed in ESCC tissues and cell lines. The biological roles of CLK4 were studied with gain and loss-of-function experiments. Mass spectrometry was employed to examine the effects of CLK4 on metabolic profiling. In vitro kinase assay, co-immunoprecipitation, glutathione S-transferase pulldown, chromatin immunoprecipitation and luciferase reporter were used to elucidate the relationship among CLK4, microphthalmia-associated transcription factor (MITF), COP1 and ZRANB1. RESULTS: CLK4 down-regulation was observed in ESCC cell lines and clinical samples and associated with the methylation of its promoter. Low levels of CLK4 promoted ESCC development by affecting the purine synthesis pathway and nicotinamide adenine dinucleotide phosphate (NADPH)/nicotinamide adenine dinucleotide phosphate (NADP+ ) ratio. Interestingly, CLK4 inhibited ESCC development by blocking MITF-enhanced de novo purine synthesis and redox balance. Mechanistically, wild type CLK4 (WT-CLK4) but not kinase-dead CLK4-K189R mutant phosphorylated MITF at Y360. This modification promoted its interaction with E3 ligase COP1 and its K63-linked ubiquitination at K308/K372, leading to sequestosome 1 recognition and autophagic degradation. However, the deubiquitinase ZRANB1 rescued MITF ubiquitination and degradation. In turn, MITF bound to E- rather than M-boxes in CLK4 promoter and transcriptionally down-regulated its expression in ESCC. Clinically, the negative correlations were observed between CLK4, MITF, and purine metabolic markers, which predicts a poor clinical outcome of ESCC patients. Notably, CLK4 itself was a redox-sensitive kinase, and its methionine oxidation at M307 impaired kinase activity, enhanced mitochondria length and inhibited lipid peroxidation, contributing to ESCC. CONCLUSIONS: Our data highlight the potential role of CLK4 in modulating redox status and nucleotide metabolism, suggesting potential therapeutic targets in ESCC treatment.
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Neoplasias Esofágicas/genética , Metionina/metabolismo , Factor de Transcripción Asociado a Microftalmía/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/farmacología , Proteínas Tirosina Quinasas/farmacología , Autofagia/efectos de los fármacos , Autofagia/genética , Línea Celular/metabolismo , Neoplasias Esofágicas/tratamiento farmacológico , Homeostasis/efectos de los fármacos , Homeostasis/genética , Humanos , Metionina/genética , Factor de Transcripción Asociado a Microftalmía/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Tirosina Quinasas/metabolismoRESUMEN
BACKGROUND: Post-translational modification (PTM) is one of the major regulatory mechanism for protein activities. To understand the function of PTMs, mutants that prevent or mimic the modification are frequently utilized. The endogenous proteins are usually depleted while the point mutations are expressed. A common strategy to accomplish these tasks includes two-steps: First, a cell line stably expressing shRNA for protein depletion is generated, then an RNAi-resistance construct is introduced to express mutant. However, these steps are time- and labor-consuming. More importantly, shRNA and mutant protein are frequently expressed in different cells at different time, which significantly disturbs the conclusions. METHODS: To overcome these technical problems, we developed a lentiviral based one-plasmid system that allowed concurrent expression of shRNA and mutant protein. The puromycin-resistant gene was inserted for the selection of stable-expression cells. RESULTS: Using this plasmid, we efficiently replaced the endogenous proteins with comparable levels of exogenous proteins for LDHB and PKM2, two glycolytic enzymes regulated by PTM in cancer cells. The system was also successfully exploited in evaluating the role of phosphorylation of LDHB serine 162 in multiple in vitro and in vivo assays. CONCLUSION: Thus, we have developed an efficient one-plasmid system to replace endogenous protein with point mutations for the functional study of PTM.
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Proteínas Portadoras/genética , L-Lactato Deshidrogenasa/genética , Proteínas de la Membrana/genética , Plásmidos/genética , Mutación Puntual , ARN Interferente Pequeño/farmacología , Hormonas Tiroideas/genética , Animales , Línea Celular Tumoral , Células HCT116 , Células HeLa , Células Hep G2 , Humanos , Isoenzimas/genética , Masculino , Ratones , Fosforilación , Procesamiento Proteico-Postraduccional , Interferencia de ARN , Serina/metabolismo , Proteínas de Unión a Hormona TiroideRESUMEN
Background: Gastric microbiota may be involved in gastric cancer. The relationship between gastrointestinal microbes and the risk of gastric cancer is unclear. This study aimed to explore the gastric and intestinal bacteria associated with gastritis and gastric precancerous lesions. We conducted a case-control study by performing 16S rRNA gene analysis of gastric biopsies, juices, and stool samples from 148 cases with gastritis or gastric precancerous lesions from Anhui and neighboring provinces, China. And we validated our findings in public datasets. Results: Analysis of microbial sequences revealed decreased bacterial alpha diversity in gastric bacteria during the progression of gastritis. Helicobacter pylori was the main contributor to the decreased microbial composition and diversity in the gastric mucosa and had little influence on the microbiota of gastric juice and feces. The gastric mucosal genera Gemella, Veillonella, Streptococcus, Actinobacillus, and Hemophilus had the higher degree of centrality across the progression of gastric precancerous lesions. And Acinetobacter may contribute to the occurrence of intraepithelial neoplasia. In addition, the microbial model of H. pylori-positive gastric biopsies and feces showed value in the prediction of gastric precancerous lesions. Conclusions: This study identified associations between gastric precancerous lesions and gastric microbiota, as well as the changes in intestinal microbiota, and explored their values in the prediction of gastric precancerous lesions.