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1.
Cell ; 187(9): 2288-2304.e27, 2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38565142

ABSTRACT

Taurine is used to bolster immunity, but its effects on antitumor immunity are unclear. Here, we report that cancer-related taurine consumption causes T cell exhaustion and tumor progression. The taurine transporter SLC6A6 is correlated with aggressiveness and poor outcomes in multiple cancers. SLC6A6-mediated taurine uptake promotes the malignant behaviors of tumor cells but also increases the survival and effector function of CD8+ T cells. Tumor cells outcompete CD8+ T cells for taurine by overexpressing SLC6A6, which induces T cell death and malfunction, thereby fueling tumor progression. Mechanistically, taurine deficiency in CD8+ T cells increases ER stress, promoting ATF4 transcription in a PERK-JAK1-STAT3 signaling-dependent manner. Increased ATF4 transactivates multiple immune checkpoint genes and induces T cell exhaustion. In gastric cancer, we identify a chemotherapy-induced SP1-SLC6A6 regulatory axis. Our findings suggest that tumoral-SLC6A6-mediated taurine deficiency promotes immune evasion and that taurine supplementation reinvigorates exhausted CD8+ T cells and increases the efficacy of cancer therapies.


Subject(s)
CD8-Positive T-Lymphocytes , Membrane Glycoproteins , Taurine , Taurine/metabolism , CD8-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/metabolism , Animals , Humans , Mice , Cell Line, Tumor , Mice, Inbred C57BL , Endoplasmic Reticulum Stress , Activating Transcription Factor 4/metabolism , Signal Transduction , Female , Membrane Transport Proteins/metabolism , Membrane Transport Proteins/genetics , STAT3 Transcription Factor/metabolism
2.
Cell ; 149(3): 605-17, 2012 Apr 27.
Article in English | MEDLINE | ID: mdl-22541431

ABSTRACT

Haploid cells are amenable for genetic analysis. Recent success in the derivation of mouse haploid embryonic stem cells (haESCs) via parthenogenesis has enabled genetic screening in mammalian cells. However, successful generation of live animals from these haESCs, which is needed to extend the genetic analysis to the organism level, has not been achieved. Here, we report the derivation of haESCs from androgenetic blastocysts. These cells, designated as AG-haESCs, partially maintain paternal imprints, express classical ESC pluripotency markers, and contribute to various tissues, including the germline, upon injection into diploid blastocysts. Strikingly, live mice can be obtained upon injection of AG-haESCs into MII oocytes, and these mice bear haESC-carried genetic traits and develop into fertile adults. Furthermore, gene targeting via homologous recombination is feasible in the AG-haESCs. Our results demonstrate that AG-haESCs can be used as a genetically tractable fertilization agent for the production of live animals via injection into oocytes.


Subject(s)
Embryonic Stem Cells/cytology , Genetic Techniques , Mice, Transgenic , Animals , Blastocyst/cytology , Cell Nucleus/metabolism , Female , Gene Targeting , Male , Mice , Mice, Inbred C57BL , Oocytes/cytology , Oocytes/metabolism
3.
J Biol Chem ; 300(8): 107522, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38960034

ABSTRACT

Chemotherapy is still the main therapeutic strategy for gastric cancer (GC). However, most patients eventually acquire multidrug resistance (MDR). Hyperactivation of the EGFR signaling pathway contributes to MDR by promoting cancer cell proliferation and inhibiting apoptosis. We previously identified the secreted protein CGA as a novel ligand of EGFR and revealed a CGA/EGFR/GATA2 positive feedback circuit that confers MDR in GC. Herein, we outline a microRNA-based treatment approach for MDR reversal that targets both CGA and GATA2. We observed increased expression of CGA and GATA2 and increased activation of EGFR in GC samples. Bioinformatic analysis revealed that miR-107 could simultaneously target CGA and GATA2, and the low expression of miR-107 was correlated with poor prognosis in GC patients. The direct interactions between miR-107 and CGA or GATA2 were validated by luciferase reporter assays and Western blot analysis. Overexpression of miR-107 in MDR GC cells increased their susceptibility to chemotherapeutic agents, including fluorouracil, adriamycin, and vincristine, in vitro. Notably, intratumor injection of the miR-107 prodrug enhanced MDR xenograft sensitivity to chemotherapies in vivo. Molecularly, targeting CGA and GATA2 with miR-107 inhibited EGFR downstream signaling, as evidenced by the reduced phosphorylation of ERK and AKT. These results suggest that miR-107 may contribute to the development of a promising therapeutic approach for the treatment of MDR in GC.


Subject(s)
Drug Resistance, Multiple , Drug Resistance, Neoplasm , ErbB Receptors , GATA2 Transcription Factor , MicroRNAs , Stomach Neoplasms , MicroRNAs/genetics , MicroRNAs/metabolism , Stomach Neoplasms/genetics , Stomach Neoplasms/metabolism , Stomach Neoplasms/pathology , Stomach Neoplasms/drug therapy , Humans , GATA2 Transcription Factor/metabolism , GATA2 Transcription Factor/genetics , ErbB Receptors/metabolism , ErbB Receptors/genetics , Animals , Drug Resistance, Multiple/genetics , Cell Line, Tumor , Mice , Gene Expression Regulation, Neoplastic , Signal Transduction/drug effects , Female , Feedback, Physiological , Mice, Nude , Male , Mice, Inbred BALB C , Xenograft Model Antitumor Assays
4.
Gastroenterology ; 167(2): 264-280, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38417530

ABSTRACT

BACKGROUND & AIMS: Hepatocellular carcinoma (HCC) is characterized by an immune-suppressive microenvironment, which contributes to tumor progression, metastasis, and immunotherapy resistance. Identification of HCC-intrinsic factors regulating the immunosuppressive microenvironment is urgently needed. Here, we aimed to elucidate the role of SYR-Related High-Mobility Group Box 18 (SOX18) in inducing immunosuppression and to validate novel combination strategies for SOX18-mediated HCC progression and metastasis. METHODS: The role of SOX18 in HCC was investigated in orthotopic allografts and diethylinitrosamine/carbon tetrachloride-induced spontaneous models by using murine cell lines, adeno-associated virus 8, and hepatocyte-specific knockin and knockout mice. The immune cellular composition in the HCC microenvironment was evaluated by flow cytometry and immunofluorescence. RESULTS: SOX18 overexpression promoted the infiltration of tumor-associated macrophages (TAMs) and regulatory T cells (Tregs) while diminishing cytotoxic T cells to facilitate HCC progression and metastasis in cell-derived allografts and chemically induced HCC models. Mechanistically, transforming growth factor-beta 1 (TGF-ß1) upregulated SOX18 expression by activating the Smad2/3 complex. SOX18 transactivated chemokine (C-X-C motif) ligand 12 (CXCL12) and programmed death ligand 1 (PD-L1) to induce the immunosuppressive microenvironment. CXCL12 knockdown significantly attenuated SOX18-induced TAMs and Tregs accumulation and HCC dissemination. Antagonism of chemokine receptor 4 (CXCR4), the cognate receptor of CXCL12, or selective knockout of CXCR4 in TAMs or Tregs likewise abolished SOX18-mediated effects. TGFßR1 inhibitor Vactosertib or CXCR4 inhibitor AMD3100 in combination with anti-PD-L1 dramatically inhibited SOX18-mediated HCC progression and metastasis. CONCLUSIONS: SOX18 promoted the accumulation of immunosuppressive TAMs and Tregs in the microenvironment by transactivating CXCL12 and PD-L1. CXCR4 inhibitor or TGFßR1 inhibitor in synergy with anti-PD-L1 represented a promising combination strategy to suppress HCC progression and metastasis.


Subject(s)
B7-H1 Antigen , Benzylamines , Carcinoma, Hepatocellular , Chemokine CXCL12 , Cyclams , Disease Progression , Liver Neoplasms , Receptors, CXCR4 , SOXF Transcription Factors , T-Lymphocytes, Regulatory , Transforming Growth Factor beta1 , Tumor Microenvironment , Tumor-Associated Macrophages , Up-Regulation , Animals , Carcinoma, Hepatocellular/pathology , Carcinoma, Hepatocellular/immunology , Carcinoma, Hepatocellular/genetics , Carcinoma, Hepatocellular/metabolism , Liver Neoplasms/pathology , Liver Neoplasms/immunology , Liver Neoplasms/genetics , Liver Neoplasms/metabolism , SOXF Transcription Factors/metabolism , SOXF Transcription Factors/genetics , B7-H1 Antigen/metabolism , B7-H1 Antigen/genetics , Tumor Microenvironment/immunology , Humans , Receptors, CXCR4/metabolism , Receptors, CXCR4/genetics , Transforming Growth Factor beta1/metabolism , Mice , Chemokine CXCL12/metabolism , Chemokine CXCL12/genetics , Cyclams/pharmacology , Benzylamines/pharmacology , T-Lymphocytes, Regulatory/immunology , T-Lymphocytes, Regulatory/metabolism , Cell Line, Tumor , Tumor-Associated Macrophages/metabolism , Tumor-Associated Macrophages/immunology , Mice, Knockout , Gene Expression Regulation, Neoplastic , Signal Transduction , Immune Checkpoint Inhibitors/pharmacology , Immune Checkpoint Inhibitors/therapeutic use , Mice, Inbred C57BL , Diethylnitrosamine/toxicity , Male
5.
Genes Dev ; 31(16): 1655-1665, 2017 08 15.
Article in English | MEDLINE | ID: mdl-28903979

ABSTRACT

Starvation induces liver autophagy, which is thought to provide nutrients for use by other organs and thereby maintain whole-body homeostasis. Here we demonstrate that O-linked ß-N-acetylglucosamine (O-GlcNAc) transferase (OGT) is required for glucagon-stimulated liver autophagy and metabolic adaptation to starvation. Genetic ablation of OGT in mouse livers reduces autophagic flux and the production of glucose and ketone bodies. Upon glucagon-induced calcium signaling, calcium/calmodulin-dependent kinase II (CaMKII) phosphorylates OGT, which in turn promotes O-GlcNAc modification and activation of Ulk proteins by potentiating AMPK-dependent phosphorylation. These findings uncover a signaling cascade by which starvation promotes autophagy through OGT phosphorylation and establish the importance of O-GlcNAc signaling in coupling liver autophagy to nutrient homeostasis.


Subject(s)
Autophagy , Calcium Signaling , Liver/metabolism , N-Acetylglucosaminyltransferases/metabolism , Nutritional Physiological Phenomena , Adaptation, Biological , Animals , Autophagy-Related Protein 5/physiology , Autophagy-Related Protein-1 Homolog/metabolism , Calcium-Calmodulin-Dependent Protein Kinase Type 2/metabolism , Cells, Cultured , Glucagon/pharmacology , HEK293 Cells , HeLa Cells , Humans , Inositol 1,4,5-Trisphosphate Receptors/metabolism , Liver/drug effects , Liver/enzymology , Mice, Inbred C57BL , N-Acetylglucosaminyltransferases/physiology
6.
Br J Cancer ; 130(4): 597-612, 2024 03.
Article in English | MEDLINE | ID: mdl-38184692

ABSTRACT

BACKGROUND: The expression of Egl-9 family hypoxia-inducible factor 3 (EGLN3) is notably decreased in various malignancies, including gastric cancer (GC). While the predominant focus has been on the hydroxylase activity of EGLN3 for its antitumour effects, recent findings have suggested nonenzymatic roles for EGLN3. METHODS: This study assessed the clinical significance of EGLN3 expression in GC and explored the connection between EGLN3 DNA promoter methylation and transcriptional silencing. To investigate the effect of EGLN3 on GC cells, a gain-of-function strategy was adopted. RNA sequencing was conducted to identify the key effector molecules and signalling pathways associated with EGLN3. RESULTS: EGLN3 expression was significantly reduced in GC tissues, correlating with poorer patient prognosis. EGLN3 hypermethylation disrupts transcriptional equilibrium, contributing to deeper tumour invasion and lymph node metastasis, thus exacerbating GC progression. Conversely, restoration of EGLN3 expression in GC cells substantially inhibited cell proliferation and metastasis. EGLN3 was also found to impede the malignant progression of GC cells by downregulating Jumonji C domain-containing protein 8-mediated activation of the NF-κB pathway, independent of its hydroxylase activity. CONCLUSIONS: EGLN3 has the potential to hinder the spread of GC cells through a nonenzymatic mechanism, thereby shedding light on the complex nature of GC progression.


Subject(s)
NF-kappa B , Stomach Neoplasms , Humans , NF-kappa B/genetics , NF-kappa B/metabolism , Stomach Neoplasms/pathology , Signal Transduction/genetics , DNA Methylation , Gene Expression Regulation, Neoplastic , Mixed Function Oxygenases/genetics , Cell Line, Tumor , Cell Proliferation/genetics , Hypoxia-Inducible Factor-Proline Dioxygenases/genetics , Hypoxia-Inducible Factor-Proline Dioxygenases/metabolism
7.
J Hepatol ; 2024 Aug 22.
Article in English | MEDLINE | ID: mdl-39181214

ABSTRACT

BACKGROUND & AIMS: The optimal timing of measurement and hemodynamic targets of portacaval pressure gradient (PPG) after transjugular intrahepatic portosystemic shunt (TIPS) placement remain unclear. This study aimed to identify the ideal moment for hemodynamic measurements and the optimal target of PPG in patients undergoing covered TIPS for variceal bleeding. METHODS: Between May 2018 and December 2021, 466 consecutive patients with recurrent variceal bleeding treated with covered TIPS were prospectively included. Post-TIPS PPG was measured immediately (immediate PPG), 24-72 hours (early PPG), and again 1 month (late PPG) after TIPS placement. The agreement among PPGs measured at different time points was assessed by intra-class correlation coefficient (ICC) and Bland-Altman method. The unadjusted and confounder-adjusted effects of PPGs on clinical outcomes (portal hypertensive complications [PHCs], overt hepatic encephalopathy [OHE], further decompensation, and death) were assessed using Fine and Gray competing risk regression models. RESULTS: The agreement between early PPG and late PPG (ICC: 0.34) was better than that between immediate PPG and late PPG (ICC: 0.23, p <0.001). Early PPG revealed an excellent predictive value for PHCs (early PPG≥ vs. <12 mmHg: adjusted hazard ratio 2.17, 95% CI 1.33-3.55, p = 0.002) and OHE (0.40, 95% CI 0.17-0.91, p = 0.030), while immediate PPG did not. Late PPG showed a predictive value for PHC risk but not OHE. By targeting the lowest risk of further decompensation, we identified an optimal hemodynamic target with early PPG ranging from 11 to 14 mmHg that was associated with a decreased risk of OHE and effective prevention of PHC. CONCLUSIONS: PPG measured 24 to 72 hours after TIPS correlates with long-term PPG and clinical outcomes, and a hemodynamic target PPG of 11-14 mmHg is associated with reduced encephalopathy but not compromised clinical efficacy. IMPACT AND IMPLICATIONS: The optimal timing of measurement and hemodynamic targets of portacaval pressure gradient (PPG) after transjugular intrahepatic portosystemic shunt (TIPS) remain unclear. Here we show that post-TIPS PPG measured at least 24 hours but not immediately after the procedure correlated with long-term PPG and clinical events. Thus, PPG measurements taken at least 24 hours after TIPS should be used to guide decision making in order to improve clinical outcomes. Targeting a post-TIPS PPG of 11-14 mmHg or a 20%-50% relative reduction from pre-TIPS baseline measured 24-72 hours after the procedure was associated with reduced encephalopathy but not compromised clinical efficacy. Thus, these criteria could be used to guide TIPS creation and revision in patients with cirrhosis and variceal bleeding undergoing covered TIPS. CLINICAL TRIAL REGISTRATION NUMBER: ClinicalTrials.gov, ID: NCT03590288.

8.
Pharmacoepidemiol Drug Saf ; 33(8): e5880, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39135518

ABSTRACT

BACKGROUND: Polypharmacy (PP) is common in elderly population and associated with some adverse clinical outcomes and increases healthcare burdens. We performed this systemic review and meta-analysis to estimate worldwide prevalence of PP and explore associated factors in the elderly. METHODS: The PubMed, Web of Science, Cochrane Library, and Ovid EMBASE databases were searched for studies published until May 30, 2022. We included observational studies representative of general patients aged ≥60 in which PP was defined as multiple drugs ≥5. Studies were excluded if only a particular group of the elderly population (e.g., with diabetes) were included. The primary outcome was the prevalence of PP. Random-effect models were employed to estimate the overall or variable-specific pooled estimates of PP. Secondary outcomes were hyperpolypharmacy (HPP, defined as multiple drugs ≥10) and PP prevalence based on different study years, genders, locations, populations, and so forth. RESULTS: We included 122 original observational studies with an overall population of 57 328 043 individuals in the meta-analysis. The overall prevalence of PP and HPP in the elderly population worldwide was 39.1% (95% confidence interval [CI], 35.5%-42.7%) and 13.3% (95% CI, 10.4%-16.5%), respectively. The prevalence of PP in Europe, Oceania, North America, Asia, and South America was 45.8% (95% CI, 41.5%-50.2%), 45.5% (95% CI, 26.7%-64.3%), 40.8% (95% CI, 29.8%-51.6%), 29.0% (95% CI, 20.0%-38.0%), and 28.4% (95% CI, 24.0%-32.8%), respectively (p < 0.01). Multivariate meta-regressions showed geographical regions of Europe or North America, age ≥70, and residence from nursing homes were independently associated with higher PP prevalence. CONCLUSIONS: Nearly 40% of the elderly population is exposed to PP. The prevalence of PP is significantly higher in elderly individuals aged 70 or older, in developed regions and in nursing homes. It is important to focus on avoiding inappropriate PP in this population to address the growing burden of PP.


Subject(s)
Polypharmacy , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Age Factors , Global Health/statistics & numerical data , Observational Studies as Topic , Polypharmacy/statistics & numerical data , Prevalence
9.
Cereb Cortex ; 33(5): 2037-2047, 2023 02 20.
Article in English | MEDLINE | ID: mdl-35580853

ABSTRACT

Habenular (Hb) processes negative emotions that may drive compulsive food-intake. Its functional changes were reported following laparoscopic-sleeve-gastrectomy (LSG). However, structural connectivity (SC) of Hb-homeostatic/hedonic circuits after LSG remains unclear. We selected regions implicated in homeostatic/hedonic regulation that have anatomical connections with Hb as regions-of-interest (ROIs), and used diffusion-tensor-imaging with probabilistic tractography to calculate SC between Hb and these ROIs in 30 obese participants before LSG (PreLSG) and at 12-month post-LSG (PostLSG12) and 30 normal-weight controls. Three-factor-eating-questionnaire (TFEQ) and Dutch-eating-behavior-questionnaire (DEBQ) were used to assess eating behaviors. LSG significantly decreased weight, negative emotion, and improved self-reported eating behavior. LSG increased SC between the Hb and homeostatic/hedonic regions including hypothalamus (Hy), bilateral superior frontal gyri (SFG), left amygdala (AMY), and orbitofrontal cortex (OFC). TFEQ-hunger negatively correlated with SC of Hb-Hy at PostLSG12; and increased SC of Hb-Hy correlated with reduced depression and DEBQ-external eating. TFEQ-disinhibition negatively correlated with SC of Hb-bilateral SFG at PreLSG. Increased SC of Hb-left AMY correlated with reduced DEBQ-emotional eating. Higher percentage of total weight-loss negatively correlated with SC of Hb-left OFC at PreLSG. Enhanced SC of Hb-homeostatic/hedonic regulatory regions post-LSG may contribute to its beneficial effects in improving eating behaviors including negative emotional eating, and long-term weight-loss.


Subject(s)
Laparoscopy , Obesity, Morbid , Humans , Feeding Behavior/physiology , Obesity, Morbid/psychology , Obesity, Morbid/surgery , Emotions , Gastrectomy , Weight Loss/physiology , Treatment Outcome
10.
Anal Chem ; 95(19): 7448-7457, 2023 05 16.
Article in English | MEDLINE | ID: mdl-37146305

ABSTRACT

Both N-linked glycosylation and O-linked glycosylation play essential roles in the onset and progression of various diseases including cancer, and N-/O-linked site-specific glycans have been proven to be promising biomarkers for the discrimination of cancer. However, the micro-heterogeneity and low abundance nature of N-/O-linked glycosylation, as well as the time-consuming and tedious procedures for the enrichment of O-linked intact glycopeptides, pose great challenges for their efficient and accurate characterization. In this study, we developed an integrated platform for the simultaneous enrichment and characterization of N- and O-linked intact glycopeptides from the same serum sample. By fine-tuning the experimental conditions, we demonstrated that this platform allowed the selective separation of N- and O-linked intact glycopeptides into two fractions, with 85.1% O-linked intact glycopeptides presented in the first fraction and 93.4% N-linked intact glycopeptides presented in the second fraction. Determined with high reproducibility, this platform was further applied to the differential analysis of serum samples of gastric cancer and health control, which revealed 17 and 181 significantly changed O-linked and N-linked intact glycopeptides. Interestingly, five glycoproteins containing both significant regulation of N- and O-glycosylation were observed, hinting potential co-regulation of different types of glycosylation during tumor progress. In summary, this integrated platform opened a potentially useful avenue for the global analysis of protein glycosylation and can serve as a useful tool for the characterization of N-/O-linked intact glycopeptides at the proteomics scale.


Subject(s)
Glycopeptides , Glycoproteins , Glycopeptides/analysis , Reproducibility of Results , Glycoproteins/chemistry , Glycosylation , Proteomics/methods
11.
FASEB J ; 36(4): e22244, 2022 04.
Article in English | MEDLINE | ID: mdl-35262964

ABSTRACT

Cancer immunotherapy has achieved impressive therapeutic effects in many cancers, while only a small subset of patients benefit from it and some patients even have experienced severe toxicity. It is urgent to develop a feasible large-cohort humanized mouse model to evaluate the pre-clinical efficacy and safety of cancer immunotherapy. Furthermore, developing potentially effective combination therapy between cancer immunotherapy and other therapies also needs humanized mouse model to adequately mimic clinical actual setting. Herein, we established a humanized mouse model engrafted with less human CD34+ HSCs than ever before and then evaluated reconstitution efficiency and the profiles of human immune cells in this humanized mouse model. Also, this humanized mouse model was used to evaluate the preclinical efficacy and safety of cancer immunotherapy. For each batch of CD34+ HSCs humanized mouse model, a relatively-large cohort with over 25% human CD45+ cells in peripheral blood was established. This humanized mouse model could efficiently reconstitute human innate and adaptive immune cells. This humanized mouse model supported patient-derived xenograft tumor growth and tumor infiltration of PD-1+ human T cells. Furthermore, therapeutic efficacy, re-activation of tumor-infiltrated T cells, and side effects of checkpoint blockade therapy could be monitored in this humanized mouse model. Human T cells from this humanized mouse model were successfully engineered with CD19-CAR. CD19 CAR-T cells could effectively deplete B cells and suppress tumor growth of acute lymphoblastic leukemia in vivo in this humanized mouse model. This humanized mouse model also could be used to demonstrate the efficacy of bispecific antibodies, such as anti-CD19/CD3. Overall, our work provides a feasible large-cohort humanized mouse model for evaluating a variety of cancer immunotherapy approaches including checkpoint inhibitors, adoptive cell therapy, and bispecific antibody therapy, and demonstrates that human T cells from this humanized mouse model possess anti-tumor activities in vitro and in vivo.


Subject(s)
Antibodies, Bispecific , Neoplasms , Animals , Antibodies, Bispecific/pharmacology , Antigens, CD34 , Disease Models, Animal , Hematopoietic Stem Cells , Humans , Immunotherapy , Mice , Xenograft Model Antitumor Assays
12.
Liver Int ; 43(7): 1473-1485, 2023 07.
Article in English | MEDLINE | ID: mdl-37088973

ABSTRACT

BACKGROUND AND AIMS: Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease worldwide. Aberrant lipid metabolism and accumulation of extracellular matrix proteins are hallmarks of the disease, but the underlying mechanisms are largely unknown. This study aims to elucidate the key role of sine oculis homeobox homologue 1 (SIX1) in the development of NAFLD. METHODS: Alb-Cre mice were administered the AAV9 vector for SIX1 liver-specific overexpression or knockdown. Metabolic disorders, hepatic steatosis, and inflammation were monitored in mice fed with HFHC or MCD diet. High throughput CUT&Tag analysis was employed to investigate the mechanism of SIX1 in diet-induced steatohepatitis. RESULTS: Here, we found increased SIX1 expression in the livers of NAFLD patients and animal models. Liver-specific overexpression of SIX1 using adeno-associated virus serotype 9 (AAV9) provoked more severe inflammation, metabolic disorders, and hepatic steatosis in the HFHC or MCD-induced mice model. Mechanistically, we demonstrated that SIX1 directly activated the expression of liver X receptor α (LXRα) and liver X receptor ß (LXRß), thus inducing de novo lipogenesis (DNL). In addition, our results also illustrated a critical role of SIX1 in regulating the TGF-ß pathway by increasing the levels of type I and II TGF-ß receptor (TGFßRI/TGFßRII) in hepatic stellate cells (HSCs). Finally, we found that liver-specific SIX1 deficiency could ameliorate diet-induced NAFLD pathogenesis. CONCLUSION: Our findings suggest a detrimental function of SIX1 in the progression of NAFLD. The direct regulation of LXRα/ß and TGF-ß signalling by SIX1 provides a new regulatory mechanism in hepatic steatosis and fibrosis.


Subject(s)
Non-alcoholic Fatty Liver Disease , Mice , Animals , Non-alcoholic Fatty Liver Disease/pathology , Lipogenesis/physiology , Liver/pathology , Fibrosis , Inflammation/pathology , Transforming Growth Factor beta/metabolism , Mice, Inbred C57BL , Diet, High-Fat
13.
Cereb Cortex ; 32(9): 2013-2021, 2022 04 20.
Article in English | MEDLINE | ID: mdl-34649270

ABSTRACT

Individuals with obesity (OB) prefer immediate rewards of food intake over the delayed reward of healthy well-being achieved through diet management and physical activity, compared with normal-weight controls (NW). This may reflect heightened impulsivity, an important factor contributing to the development and maintenance of obesity. However, the neural mechanisms underlying the greater impulsivity in OB remain unclear. Therefore, the current study employed functional magnetic resonance imaging with a delay discounting (DD) task to examine the association between impulsive choice and altered neural mechanisms in OB. During decision-making in the DD task, OB compared with NW had greater activation in the dorsolateral prefrontal cortex (DLPFC) and posterior parietal cortex, which was associated with greater discounting rate and weaker cognitive control as measured with the Three-Factor Eating Questionnaire (TFEQ). In addition, the association between DLPFC activation and cognitive control (TFEQ) was mediated by discounting rate. Psychophysiological interaction analysis showed decreased connectivity of DLPFC-inferior parietal cortex (within executive control network [ECN]) and angular gyrus-caudate (ECN-reward) in OB relative to NW. These findings reveal that the aberrant function and connectivity in core regions of ECN and striatal brain reward regions underpin the greater impulsivity in OB and contribute to abnormal eating behaviors.


Subject(s)
Delay Discounting , Executive Function , Brain/physiology , Brain Mapping/methods , Delay Discounting/physiology , Executive Function/physiology , Humans , Impulsive Behavior/physiology , Magnetic Resonance Imaging/methods , Obesity/diagnostic imaging , Reward
14.
Gut ; 71(2): 238-253, 2022 02.
Article in English | MEDLINE | ID: mdl-34836916

ABSTRACT

OBJECTIVE: Helicobacter pylori infection is mostly a family-based infectious disease. To facilitate its prevention and management, a national consensus meeting was held to review current evidence and propose strategies for population-wide and family-based H. pylori infection control and management to reduce the related disease burden. METHODS: Fifty-seven experts from 41 major universities and institutions in 20 provinces/regions of mainland China were invited to review evidence and modify statements using Delphi process and grading of recommendations assessment, development and evaluation system. The consensus level was defined as ≥80% for agreement on the proposed statements. RESULTS: Experts discussed and modified the original 23 statements on family-based H. pylori infection transmission, control and management, and reached consensus on 16 statements. The final report consists of three parts: (1) H. pylori infection and transmission among family members, (2) prevention and management of H. pylori infection in children and elderly people within households, and (3) strategies for prevention and management of H. pylori infection for family members. In addition to the 'test-and-treat' and 'screen-and-treat' strategies, this consensus also introduced a novel third 'family-based H. pylori infection control and management' strategy to prevent its intrafamilial transmission and development of related diseases. CONCLUSION: H. pylori is transmissible from person to person, and among family members. A family-based H. pylori prevention and eradication strategy would be a suitable approach to prevent its intra-familial transmission and related diseases. The notion and practice would be beneficial not only for Chinese residents but also valuable as a reference for other highly infected areas.


Subject(s)
Family Health , Helicobacter Infections/prevention & control , Helicobacter pylori , Infection Control/organization & administration , Adolescent , Adult , Aged , Child , Child, Preschool , China , Consensus , Delphi Technique , Helicobacter Infections/diagnosis , Helicobacter Infections/transmission , Humans , Infant , Middle Aged , Young Adult
15.
Mol Cancer ; 21(1): 74, 2022 03 12.
Article in English | MEDLINE | ID: mdl-35279145

ABSTRACT

BACKGROUND: Epithelial-to-mesenchymal transition (EMT) is a process linked to metastasis and drug resistance with non-coding RNAs (ncRNAs) playing pivotal roles. We previously showed that miR-100 and miR-125b, embedded within the third intron of the ncRNA host gene MIR100HG, confer resistance to cetuximab, an anti-epidermal growth factor receptor (EGFR) monoclonal antibody, in colorectal cancer (CRC). However, whether the MIR100HG transcript itself has a role in cetuximab resistance or EMT is unknown. METHODS: The correlation between MIR100HG and EMT was analyzed by curating public CRC data repositories. The biological roles of MIR100HG in EMT, metastasis and cetuximab resistance in CRC were determined both in vitro and in vivo. The expression patterns of MIR100HG, hnRNPA2B1 and TCF7L2 in CRC specimens from patients who progressed on cetuximab and patients with metastatic disease were analyzed by RNAscope and immunohistochemical staining. RESULTS: The expression of MIR100HG was strongly correlated with EMT markers and acted as a positive regulator of EMT. MIR100HG sustained cetuximab resistance and facilitated invasion and metastasis in CRC cells both in vitro and in vivo. hnRNPA2B1 was identified as a binding partner of MIR100HG. Mechanistically, MIR100HG maintained mRNA stability of TCF7L2, a major transcriptional coactivator of the Wnt/ß-catenin signaling, by interacting with hnRNPA2B1. hnRNPA2B1 recognized the N6-methyladenosine (m6A) site of TCF7L2 mRNA in the presence of MIR100HG. TCF7L2, in turn, activated MIR100HG transcription, forming a feed forward regulatory loop. The MIR100HG/hnRNPA2B1/TCF7L2 axis was augmented in specimens from CRC patients who either developed local or distant metastasis or had disease progression that was associated with cetuximab resistance. CONCLUSIONS: MIR100HG and hnRNPA2B1 interact to control the transcriptional activity of Wnt signaling in CRC via regulation of TCF7L2 mRNA stability. Our findings identified MIR100HG as a potent EMT inducer in CRC that may contribute to cetuximab resistance and metastasis by activation of a MIR100HG/hnRNPA2B1/TCF7L2 feedback loop.


Subject(s)
Colorectal Neoplasms , Heterogeneous-Nuclear Ribonucleoprotein Group A-B , MicroRNAs , RNA, Long Noncoding , Cell Line, Tumor , Cell Movement/genetics , Cetuximab/genetics , Cetuximab/metabolism , Colorectal Neoplasms/pathology , Epithelial-Mesenchymal Transition/genetics , Gene Expression Regulation, Neoplastic , Heterogeneous-Nuclear Ribonucleoprotein Group A-B/genetics , Humans , MicroRNAs/genetics , MicroRNAs/metabolism , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , RNA, Messenger/genetics , Transcription Factor 7-Like 2 Protein/genetics , Transcription Factor 7-Like 2 Protein/metabolism , Wnt Signaling Pathway/genetics
16.
Brain Topogr ; 35(4): 453-463, 2022 07.
Article in English | MEDLINE | ID: mdl-35780276

ABSTRACT

Obesity is related to overconsumption of high-calorie (HiCal) food, which is modulated by brain reward and inhibitory control circuitries. The basal ganglia (BG) are a key set of nuclei within the reward circuitry, but obesity-associated functional and structural abnormalities of BG have not been well studied. Resting-state functional MRI with independent component analysis (ICA) and probabilistic tractography were employed to investigate differences in BG-related functional-(FC) and structural connectivity (SC) between 32 patients with obesity (OB) and 35 normal-weight (NW) participants. Compared to NW, OB showed significantly lower FC strength in the caudate nucleus within the BG network, and seed-based FC analysis showed lower FC between caudate and dorsolateral prefrontal cortex (DLPFC), which was negatively correlated with craving for HiCal food cues. Further SC analysis revealed that OB showed lower SC than NW between left caudate and left DLPFC as measured with fractional anisotropy (FA). Alterations in FC and SC between caudate and DLPFC in obese patients, which highlights the role of BG network in modulating the balance between reward and inhibitory-control.


Subject(s)
Basal Ganglia , Brain Mapping , Basal Ganglia/diagnostic imaging , Brain/diagnostic imaging , Humans , Magnetic Resonance Imaging , Obesity/diagnostic imaging
17.
Cereb Cortex ; 31(5): 2561-2573, 2021 03 31.
Article in English | MEDLINE | ID: mdl-33350441

ABSTRACT

Despite bariatric surgery being the most effective treatment for obesity, a proportion of subjects have suboptimal weight loss post-surgery. Therefore, it is necessary to understand the mechanisms behind the variance in weight loss and identify specific baseline biomarkers to predict optimal weight loss. Here, we employed functional magnetic resonance imaging (fMRI) with baseline whole-brain resting-state functional connectivity (RSFC) and a multivariate prediction framework integrating feature selection, feature transformation, and classification to prospectively identify obese patients that exhibited optimal weight loss at 6 months post-surgery. Siamese network, which is a multivariate machine learning method suitable for small sample analysis, and K-nearest neighbor (KNN) were cascaded as the classifier (Siamese-KNN). In the leave-one-out cross-validation, the Siamese-KNN achieved an accuracy of 83.78%, which was substantially higher than results from traditional classifiers. RSFC patterns contributing to the prediction consisted of brain networks related to salience, reward, self-referential, and cognitive processing. Further RSFC feature analysis indicated that the connection strength between frontal and parietal cortices was stronger in the optimal versus the suboptimal weight loss group. These findings show that specific RSFC patterns could be used as neuroimaging biomarkers to predict individual weight loss post-surgery and assist in personalized diagnosis for treatment of obesity.


Subject(s)
Bariatric Surgery , Brain/diagnostic imaging , Obesity/diagnostic imaging , Weight Loss , Adult , Brain/physiopathology , Cognition , Connectome , Female , Functional Neuroimaging , Humans , Machine Learning , Magnetic Resonance Imaging , Male , Multivariate Analysis , Neural Pathways/diagnostic imaging , Neural Pathways/physiopathology , Obesity/surgery , Prognosis , Reproducibility of Results , Reward , Young Adult
18.
Cereb Cortex ; 31(12): 5676-5685, 2021 10 22.
Article in English | MEDLINE | ID: mdl-34240115

ABSTRACT

Previous functional magnetic resonance imaging (fMRI) studies have showed obesity (OB)-related alterations in intrinsic functional connectivity (FC) within and between different resting-state networks (RSNs). However, few studies have examined dynamic functional connectivity (DFC). Thus, we employed resting-state fMRI with independent component analysis (ICA) and DFC analysis to investigate the alterations in FC within and between RSNs in 56 individuals with OB and 46 normal-weight (NW) controls. ICA identified six RSNs, including basal ganglia (BG), salience network (SN), right executive control network/left executive control network, and anterior default-mode network (aDMN)/posterior default-mode network. The DFC analysis identified four FC states. OB compared with NW had more occurrences and a longer mean dwell time (MDT) in state 2 (positive connectivity of BG with other RSN) and also had higher FC of BG-SN in other states. Body mass index was positively correlated with MDT and FCs of BG-aDMN (state 2) and BG-SN (state 4). DFC analysis within more refined nodes of RSNs showed that OB had more occurrences and a longer MDT in state 1 in which caudate had positive connections with the other network nodes. The findings suggest an association between caudate-related and BG-related positive FC in OB, which was not revealed by traditional FC analysis, highlighting the utility of adding DFC to the more conventional methods.


Subject(s)
Brain Mapping , Brain , Basal Ganglia/diagnostic imaging , Brain Mapping/methods , Humans , Magnetic Resonance Imaging/methods , Neural Pathways/diagnostic imaging , Obesity/diagnostic imaging
19.
Cereb Cortex ; 31(2): 1284-1295, 2021 01 05.
Article in English | MEDLINE | ID: mdl-33037819

ABSTRACT

The biological mediators that support cognitive-control and long-term weight-loss after laparoscopic sleeve gastrectomy (LSG) remain unclear. We measured peripheral appetitive hormones and brain functional-connectivity (FC) using magnetic-resonance-imaging with food cue-reactivity task in 25 obese participants at pre, 1 month, and 6 month after LSG, and compared with 30 normal weight controls. We also used diffusion-tensor-imaging to explore whether LSG increases brain structural-connectivity (SC) of regions involved in food cue-reactivity. LSG significantly decreased BMI, craving for high-calorie food cues, ghrelin, insulin, and leptin levels, and increased self-reported cognitive-control of eating behavior. LSG increased FC between the right dorsolateral prefrontal cortex (DLPFC) and the pregenual anterior cingulate cortex (pgACC) and increased SC between DLPFC and ACC at 1 month and 6 month after LSG. Reduction in BMI correlated negatively with increased FC of right DLPFC-pgACC at 1 month and with increased SC of DLPFC-ACC at 1 month and 6 month after LSG. Reduction in craving for high-calorie food cues correlated negatively with increased FC of DLPFC-pgACC at 6 month after LSG. Additionally, SC of DLPFC-ACC mediated the relationship between lower ghrelin levels and greater cognitive control. These findings provide evidence that LSG improved functional and structural connectivity in prefrontal regions, which contribute to enhanced cognitive-control and sustained weight-loss following surgery.


Subject(s)
Brain/diagnostic imaging , Craving/physiology , Gastrectomy/trends , Nerve Net/diagnostic imaging , Obesity/diagnostic imaging , Weight Loss/physiology , Adult , Biomarkers/blood , Brain/metabolism , Female , Hormones/blood , Humans , Laparoscopy/trends , Magnetic Resonance Imaging/trends , Male , Nerve Net/metabolism , Obesity/blood , Obesity/surgery
20.
Clin Auton Res ; 32(4): 237-247, 2022 08.
Article in English | MEDLINE | ID: mdl-35864386

ABSTRACT

OBJECTIVE: Brain imaging studies have shown insula-related functional and structural abnormalities in patients with obesity. Laparoscopic sleeve gastrectomy is currently an effective procedure for treating obesity, which promotes acute recovery of brain functional and structural abnormalities in obese patients. The aim of this study was to investigate the long-term impact of laparoscopic sleeve gastrectomy on insula-related structural and functional connectivity. METHODS: Diffusion tensor imaging and resting-state functional magnetic resonance imaging were employed to investigate laparoscopic sleeve gastrectomy-induced changes in insula-related structural connectivity and corresponding resting-state functional connectivity in 25 obese patients prior to (PreLSG) and 12 months post-surgery (PostLSG12). RESULTS: Results showed significant increases in fractional anisotropy and axial diffusivity between the right insula and anterior cingulate cortex, and higher fractional anisotropy of left insula-putamen, left insula-caudate and anterior cingulate cortex-right posterior cingulate cortex/precuneus at PostLSG12 compared with PreLSG. There were significant negative correlations between axial diffusivity of right insula-anterior cingulate cortex and body mass index, and fractional anisotropy of right insula-anterior cingulate cortex with scores on external eating at PostLSG12. Anxiety and depressive status ratings were negatively correlated with fractional anisotropy of left insula-putamen at PostLSG12. In addition, there was a significant decrease in resting-state functional connectivity between left insula and left caudate. CONCLUSIONS: These findings demonstrate long-term changes in insula-related structural and functional connectivity abnormalities promoted by laparoscopic sleeve gastrectomy, which highlight its strong association with long-term weight loss and improvement in eating behaviors.


Subject(s)
Diffusion Tensor Imaging , Laparoscopy , Gastrectomy , Humans , Magnetic Resonance Imaging/methods , Obesity/diagnostic imaging , Obesity/surgery
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