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1.
Immunity ; 56(1): 32-42, 2023 01 10.
Article in English | MEDLINE | ID: mdl-36630916

ABSTRACT

The metabolic stress occurring in the tumor microenvironment (TME) hampers T cell anti-tumor immunity by disturbing T cell metabolic and epigenetic programs. Recent studies are making headway toward identifying strategies to unleash T cell activities by targeting T cell metabolism. Furthermore, efforts have been made to improve the efficacy of immune checkpoint blockade and adoptive cell transfer therapies. However, distinct treatment outcomes across different cancers raise the question of whether our understanding of the features of CD8+ T cells within the TME are universal, regardless of their tissue of origin. Here, we review the common and distinct environmental factors affecting CD8+ T cells across tumors. Moreover, we discuss how distinct tissue-specific niches are interpreted by CD8+ T cells based on studies on tissue-resident memory T (Trm) cells and how these insights can pave the way for a better understanding of the metabolic regulation of CD8+ T cell differentiation and anti-tumor immunity.


Subject(s)
CD8-Positive T-Lymphocytes , Neoplasms , Humans , Neoplasms/metabolism , Lymphocyte Activation , Immunotherapy, Adoptive , Tumor Microenvironment
2.
Nature ; 628(8008): 569-575, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38570681

ABSTRACT

Shuotheriids are Jurassic mammaliaforms that possess pseudotribosphenic teeth in which a pseudotalonid is anterior to the trigonid in the lower molar, contrasting with the tribosphenic pattern of therian mammals (placentals, marsupials and kin) in which the talonid is posterior to the trigonid1-4. The origin of the pseudotribosphenic teeth remains unclear, obscuring our perception of shuotheriid affinities and the early evolution of mammaliaforms1,5-9. Here we report a new Jurassic shuotheriid represented by two skeletal specimens. Their complete pseudotribosphenic dentitions allow reidentification of dental structures using serial homology and the tooth occlusal relationship. Contrary to the conventional view1,2,6,10,11, our findings show that dental structures of shuotheriids can be homologized to those of docodontans and partly support homologous statements for some dental structures between docodontans and other mammaliaforms6,12. The phylogenetic analysis based on new evidence removes shuotheriids from the tribosphenic ausktribosphenids (including monotremes) and clusters them with docodontans to form a new clade, Docodontiformes, that is characterized by pseudotribosphenic features. In the phylogeny, docodontiforms and 'holotherians' (Kuehneotherium, monotremes and therians)13 evolve independently from a Morganucodon-like ancestor with triconodont molars by labio-lingual widening their posterior teeth for more efficient food processing. The pseudotribosphenic pattern passed a cusp semitriangulation stage9, whereas the tribosphenic pattern and its precursor went through a stage of cusp triangulation. The two different processes resulted in complex tooth structures and occlusal patterns that elucidate the earliest diversification of mammaliaforms.


Subject(s)
Biological Evolution , Fossils , Mammals , Tooth , Animals , Eutheria/anatomy & histology , Mammals/anatomy & histology , Mammals/classification , Mammals/physiology , Marsupialia/anatomy & histology , Molar/anatomy & histology , Molar/physiology , Phylogeny , Tooth/anatomy & histology , Tooth/physiology , Mastication
3.
Arterioscler Thromb Vasc Biol ; 44(1): 254-270, 2024 01.
Article in English | MEDLINE | ID: mdl-37916416

ABSTRACT

BACKGROUND: Hyperglycemia-a symptom that characterizes diabetes-is highly associated with atherothrombotic complications. However, the underlying mechanism by which hyperglycemia fuels platelet activation and arterial thrombus formation is still not fully understood. METHODS: The profiles of polyunsaturated fatty acid metabolites in the plasma of patients with diabetes and healthy controls were determined with targeted metabolomics. FeCl3-induced carotid injury model was used to assess arterial thrombus formation in mice with endothelial cell (EC)-specific YAP (yes-associated protein) deletion or overexpression. Flow cytometry and clot retraction assay were used to evaluate platelet activation. RNA sequencing and multiple biochemical analyses were conducted to unravel the underlying mechanism. RESULTS: The plasma PGE2 (prostaglandin E2) concentration was elevated in patients with diabetes with thrombotic complications and positively correlated with platelet activation. The PGE2 synthetases COX-2 (cyclooxygenase-2) and mPGES-1 (microsomal prostaglandin E synthase-1) were found to be highly expressed in ECs but not in other type of vessel cells in arteries from both patients with diabetes and hyperglycemic mice, compared with nondiabetic individuals and control mice, respectively. A combination of RNA sequencing and ingenuity pathway analyses indicated the involvement of YAP signaling. EC-specific deletion of YAP limited platelet activation and arterial thrombosis in hyperglycemic mice, whereas EC-specific overexpression of YAP in mice mimicked the prothrombotic state of diabetes, without affecting hemostasis. Mechanistically, we found that hyperglycemia/high glucose-induced endothelial YAP nuclear translocation and subsequently transcriptional expression of COX-2 and mPGES-1 contributed to the elevation of PGE2 and platelet activation. Blockade of EP3 (prostaglandin E receptor 3) activation by oral administration of DG-041 reversed the hyperactivity of platelets and delayed thrombus formation in both EC-specific YAP-overexpressing and hyperglycemic mice. CONCLUSIONS: Collectively, our data suggest that hyperglycemia-induced endothelial YAP activation aggravates platelet activation and arterial thrombus formation via PGE2/EP3 signaling. Targeting EP3 with DG-041 might be therapeutic for diabetes-related thrombosis.


Subject(s)
Diabetes Mellitus , Hyperglycemia , Thrombosis , Animals , Humans , Mice , Blood Platelets/metabolism , Cyclooxygenase 2/metabolism , Diabetes Mellitus/metabolism , Dinoprostone/metabolism , Hyperglycemia/complications , Hyperglycemia/metabolism , Mice, Obese , Thrombosis/genetics , Thrombosis/metabolism
4.
Gut ; 73(7): 1169-1182, 2024 Jun 06.
Article in English | MEDLINE | ID: mdl-38395437

ABSTRACT

OBJECTIVE: Hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC), mostly characterised by HBV integrations, is prevalent worldwide. Previous HBV studies mainly focused on a few hotspot integrations. However, the oncogenic role of the other HBV integrations remains unclear. This study aimed to elucidate HBV integration-induced tumourigenesis further. DESIGN: Here, we illuminated the genomic structures encompassing HBV integrations in 124 HCCs across ages using whole genome sequencing and Nanopore long reads. We classified a repertoire of integration patterns featured by complex genomic rearrangement. We also conducted a clustered regularly interspaced short palindromic repeat (CRISPR)-based gain-of-function genetic screen in mouse hepatocytes. We individually activated each candidate gene in the mouse model to uncover HBV integration-mediated oncogenic aberration that elicits tumourigenesis in mice. RESULTS: These HBV-mediated rearrangements are significantly enriched in a bridge-fusion-bridge pattern and interchromosomal translocations, and frequently led to a wide range of aberrations including driver copy number variations in chr 4q, 5p (TERT), 6q, 8p, 16q, 9p (CDKN2A/B), 17p (TP53) and 13q (RB1), and particularly, ultra-early amplifications in chr8q. Integrated HBV frequently contains complex structures correlated with the translocation distance. Paired breakpoints within each integration event usually exhibit different microhomology, likely mediated by different DNA repair mechanisms. HBV-mediated rearrangements significantly correlated with young age, higher HBV DNA level and TP53 mutations but were less prevalent in the patients subjected to prior antiviral therapies. Finally, we recapitulated the TONSL and TMEM65 amplification in chr8q led by HBV integration using CRISPR/Cas9 editing and demonstrated their tumourigenic potentials. CONCLUSION: HBV integrations extensively reshape genomic structures and promote hepatocarcinogenesis (graphical abstract), which may occur early in a patient's life.


Subject(s)
Carcinoma, Hepatocellular , Hepatitis B virus , Liver Neoplasms , Virus Integration , Carcinoma, Hepatocellular/virology , Carcinoma, Hepatocellular/genetics , Carcinoma, Hepatocellular/pathology , Liver Neoplasms/genetics , Liver Neoplasms/virology , Liver Neoplasms/pathology , Hepatitis B virus/genetics , Humans , Virus Integration/genetics , Animals , Mice , Male , Middle Aged , Female , Adult , Whole Genome Sequencing , DNA Copy Number Variations , Aged
5.
Med Res Rev ; 44(4): 1727-1767, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38314926

ABSTRACT

Unprecedented therapeutic targeting of previously undruggable proteins has now been achieved by molecular-glue-mediated proximity-induced degradation. As a small GTPase, G1 to S phase transition 1 (GSPT1) interacts with eRF1, the translation termination factor, to facilitate the process of translation termination. Studied demonstrated that GSPT1 plays a vital role in the acute myeloid leukemia (AML) and MYC-driven lung cancer. Thus, molecular glue (MG) degraders targeting GSPT1 is a novel and promising approach for treating AML and MYC-driven cancers. In this Perspective, we briefly summarize the structural and functional aspects of GSPT1, highlighting the latest advances and challenges in MG degraders, as well as some representative patents. The structure-activity relationships, mechanism of action and pharmacokinetic features of MG degraders are emphasized to provide a comprehensive compendium on the rational design of GSPT1 MG degraders. We hope to provide an updated overview, and design guide for strategies targeting GSPT1 for the treatment of cancer.


Subject(s)
Chemistry, Pharmaceutical , Animals , Humans , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Proteolysis , Structure-Activity Relationship
6.
Cancer Cell Int ; 24(1): 129, 2024 Apr 06.
Article in English | MEDLINE | ID: mdl-38582841

ABSTRACT

BACKGROUND: The objective of this study was to determine the role and regulatory mechanism of miR-380 in cholangiocarcinoma. METHODS: The TargetScan database and a dual-luciferase reporter assay system were used to determine if LIS1 was a target gene of miR-380. The Cell Counting Kit 8 assay, flow cytometry, and Transwell assay were used to detect the effects of miR-380 and LIS1 on the proliferation, S-phase ratio, and invasiveness of HCCC-9810/HuCCT1/QBC939 cells. Western blotting was used to determine the effect of miR-380 on MMP-2/p-AKT. Immunohistochemistry detected the regulatory effect of miR-380 on the expression of MMP-2/p-AKT/LIS1. RESULTS: Expression of miR-380 in cholangiocarcinoma was decreased but expression of LIS1 was increased. LIS1 was confirmed to be a target gene of miR-380. Transfection with miR-380 mimics inhibited the proliferation, S-phase arrest, and invasion of HCCC-9810/HuCCT1/QBC939 cells, and LIS1 reversed these inhibitory effects. miR-380 inhibitor promoted proliferation, S-phase ratio, and invasiveness of HCCC-9810/HuCCT1/QBC939 cells. si-LIS1 salvaged the promotive effect of miR-380 inhibitor. Overexpression of miR-380 inhibited expression of MMP-2/p-AKT/LIS1, but miR-380 inhibitor promoted their expression. CONCLUSION: An imbalance of miR-380 expression is closely related to cholangiocarcinoma, and overexpression of miR-380 inhibits the expression of MMP-2/p-AKT by directly targeting LIS1.

7.
Environ Sci Technol ; 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38959026

ABSTRACT

Fabrication of robust isolated atom catalysts has been a research hotspot in the environment catalysis field for the removal of various contaminants, but there are still challenges in improving the reactivity and stability. Herein, through facile doping alkali metals in Pt catalyst on zirconia (Pt-Na/ZrO2), the atomically dispersed Ptδ+-O(OH)x- associated with alkali metal via oxygen bridge was successfully fabricated. This novel catalyst presented remarkably higher CO and hydrocarbon (HCs: C3H8, C7H8, C3H6, and CH4) oxidation activity than its counterpart (Pt/ZrO2). Systematically direct and solid evidence from experiments and density functional theory calculations demonstrated that the fabricated electron-rich Ptδ+-O(OH)x- related to Na species rather than the original Ptδ+-O(OH)x-, serving as the catalytically active species, can readily react with CO adsorbed on Ptδ+ to produce CO2 with significantly decreasing energy barrier in the rate-determining step from 1.97 to 0.93 eV. Additionally, owing to the strongly adsorbed and activated water by Na species, those fabricated single-site Ptδ+-O(OH)x- linked by Na species could be easily regenerated during the oxidation reaction, thus considerably boosting its oxidation reactivity and durability. Such facile construction of the alkali ion-linked active hydroxyl group was also realized by Li and K modification which could guide to the design of efficient catalysts for the removal of CO and HCs from industrial exhaust.

8.
J Am Acad Dermatol ; 90(4): 783-789, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38159645

ABSTRACT

BACKGROUND: Relapse of infantile hemangiomas after withdrawal from propranolol treatment is common. Early withdrawal is believed to increase the risk of relapse. OBJECTIVE: The objective of this study was to determine the optimal time to discontinue propranolol treatment for infantile hemangiomas. METHODS: A prospective study conducted at a tertiary referral center. RESULTS: Compared to withdrawal after 1-month maintenance treatment, withdrawal after 3-month maintenance, corresponding achieving maximum regression of infantile hemangiomas, was associated with a lower major relapse rate (P = .041). The relapse (P = .055) and adverse event rates (P = .154) between the 2 withdrawal modes were not statistically significant. Compared with direct withdrawal, the relapse (P = .396), major relapse (P = .963), and adverse event rates (P = .458) of gradual withdrawal were not statistically different. Patients with/without relapse could be best distinguished according to whether withdrawal followed a 3-month maintenance and age >13 months (area under the receiver operating characteristic curve = 0.603). Patients with/without major relapse could be best distinguished according to whether withdrawal was accompanied by 3-month maintenance (area under the receiver operating characteristic curve = 0.610). LIMITATIONS: The limitations of this study are nonrandomization and single-center design. CONCLUSIONS: The optimal propranolol withdrawal time to avoid relapse is when the patient is aged >13 months and the lesion has maintained for 3 months after reaching maximum regression, while the optimal time to prevent major relapse is after 3 months of maintenance.


Subject(s)
Hemangioma, Capillary , Hemangioma , Skin Neoplasms , Humans , Infant , Propranolol/adverse effects , Adrenergic beta-Antagonists/adverse effects , Prospective Studies , Hemangioma/drug therapy , Treatment Outcome , Skin Neoplasms/drug therapy , Skin Neoplasms/chemically induced , Administration, Oral , Recurrence
9.
Biomed Chromatogr ; 38(1): e5767, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37990839

ABSTRACT

New psychoactive substances are constantly emerging, among which ketamine analogs with the core structure of 2-amino-2-phenylcyclohexanone have attracted global attention due to their continued involvement in acute intoxications. The monitoring of these substances largely relies on the acquisition of metabolic data. However, the lack of in vitro human metabolism information for these emerging structural analogs presents significant challenges to drug control efforts. To address this challenge, we investigated the first-phase metabolism patterns of four novel ketamine structural analogs of 2-FXE [2-(ethylamino)-2-(2-fluorophenyl) cyclohexan-1-one], 2-MDCK [2-(methylamino)-2-(o-tolyl) cyclohexan-1-one], 3-DMXE [2-(ethylamino)-2-(m-tolyl) cyclohexan-1-one], and 2-DMXE [2-(ethylamino)-2-(o-tolyl) cyclohexan-1-one] utilizing human liver microsomes for the first time. Metabolites were identified using ultra-performance liquid chromatography coupled with high-resolution tandem mass spectrometry. Our findings reveal that N-dealkylation and hydroxylation are the primary metabolic reactions, alongside other notable reactions, including oxidation, reduction, and dehydration. Based on our extensive research, we propose N-dealkylation and hydroxylation metabolites as appropriate analytical markers for monitoring the consumption of these substances.


Subject(s)
Ketamine , Microsomes, Liver , Humans , Microsomes, Liver/metabolism , Tandem Mass Spectrometry/methods , Ketamine/metabolism , Liquid Chromatography-Mass Spectrometry , Hydroxylation , Chromatography, High Pressure Liquid/methods
10.
Int J Phytoremediation ; 26(6): 894-902, 2024.
Article in English | MEDLINE | ID: mdl-37941161

ABSTRACT

Improvement of selenium (Se) uptake in fruit tree can improve the source of food Se for humans. In this study, the effect of various abscisic acid (ABA) concentrations on the Se uptake in Cyphomandra betacea Sendt. (Solanum betaceum Cav.) seedlings was studied under Se stress. Only the concentration of 20 µmol/L ABA promoted the growth of C. betacea seedlings by increasing the biomass and regulating the resistance physiology under Se stress. ABA also increased the Se content in C. betacea seedlings under Se stress. The concentration of ABA at 20 µmol/L got the maximum root Se and shoot Se contents, which increased by 76.64% and 55.83%, respectively, compared with the control. Correlation and grey relational analyses showed that the peroxidase activity and proline content had the first two closest relationship with the shoot Se content. This study shows that ABA can promote the Se uptake in C. betacea under Se stress, and the concentration of 20 µmol/L ABA is the optimum for Se uptake and growth of C. betacea.


Under selenium (Se) stress, abscisic acid (ABA) promotes the Se uptake in Cyphomandra betacea Sendt. (Solanum betaceum Cav.) seedlings, but only the concentration of 20 µmol/L ABA promotes the growth of C. betacea seedlings. The shoot Se content is most closely correlated with the peroxidase activity and proline content. This study shows that ABA can promote the Se uptake in C. betacea under Se stress.


Subject(s)
Selenium , Solanum , Humans , Seedlings , Selenium/pharmacology , Abscisic Acid/pharmacology , Biodegradation, Environmental
11.
Int J Phytoremediation ; 26(4): 569-578, 2024.
Article in English | MEDLINE | ID: mdl-37684742

ABSTRACT

To promote the selenium (Se) uptakes in fruit trees under Se-contaminated soil, the effects of water extract of Fagopyrum dibotrys (D. Don) Hara straw on the Se accumulation in peach seedlings under selenium-contaminated soil were studied. The results showed that the root biomass, chlorophyll content, activities of antioxidant enzymes, and soluble protein content of peach seedlings were increased by the F. dibotrys straw extract. The different forms of Se (total Se, inorganic Se, and organic Se) were also increased in peach seedlings following treatment with the F. dibotrys straw extract. The highest total shoot Se content was treated by the 300-fold dilution of F. dibotrys straw, which was 30.87% higher than the control. The F. dibotrys straw extract also increased the activities of adenosine triphosphate sulfurase (ATPS), and adenosine 5'-phosphosulfate reductase (APR) in peach seedlings, but decreased the activity of serine acetyltransferase (SAT). Additionally, correlation and grey relational analyses revealed that chlorophyll a content, APR activity, and root biomass were closely associated with the total shoot Se content. Overall, this study shows that the water extract of F. dibotrys straw can promote Se uptake in peach seedlings, and 300-fold dilution is the most suitable concentration.


The water extract of Fagopyrum dibotrys (D. Don) Hara straw promoted the selenium (Se) uptake in peach seedlings under selenium-contaminated soil. The concentration of F. dibotrys straw extract showed a quadratic polynomial regression relationship with the total root and shoot Se. Furthermore, chlorophyll a content, APR activity, and root biomass were closely associated with the total shoot Se. This study shows that water extract of F. dibotrys straw can promote Se uptake in peach seedlings, and 300-fold dilution is the most suitable concentration.


Subject(s)
Fagopyrum , Prunus persica , Selenium , Biodegradation, Environmental , Chlorophyll A/analysis , Fagopyrum/metabolism , Prunus persica/metabolism , Seedlings/chemistry , Selenium/metabolism , Soil , Water/analysis
12.
Apoptosis ; 28(7-8): 1154-1167, 2023 08.
Article in English | MEDLINE | ID: mdl-37149513

ABSTRACT

Breast cancer (BC) has threatened women worldwide for a long time, and novel treatments are needed. Ferroptosis is a new form of regulated cell death that is a potential therapeutic target for BC. In this study, we identified Escin, a traditional Chinese medicine, as a possible supplement for existing chemotherapy strategies. Escin inhibited BC cell growth in vitro and in vivo, and ferroptosis is probable to be the main cause for Escin-induced cell death. Mechanistically, Escin significantly downregulated the protein level of GPX4, while overexpression of GPX4 could reverse the ferroptosis triggered by Escin. Further study revealed that Escin could promote G6PD ubiquitination and degradation, thus inhibiting the expression of GPX4 and contributing to the ferroptosis. Moreover, proteasome inhibitor MG132 or G6PD overexpression could partially reverse Escin-induced ferroptosis, when G6PD knockdown aggravated that. In vivo study also supported that downregulation of G6PD exacerbated tumor growth inhibition by Escin. Finally, our data showed that cell apoptosis was dramatically elevated by Escin combined with cisplatin in BC cells. Taken together, these results suggest that Escin inhibits tumor growth in vivo and in vitro via regulating the ferroptosis mediated by G6PD/GPX4 axis. Our findings provide a promising therapeutic strategy for BC.


Subject(s)
Breast Neoplasms , Ferroptosis , Female , Humans , Breast Neoplasms/drug therapy , Breast Neoplasms/genetics , Cisplatin/pharmacology , Cisplatin/therapeutic use , Escin , Ferroptosis/genetics , Apoptosis
13.
Anal Chem ; 95(47): 17263-17272, 2023 11 28.
Article in English | MEDLINE | ID: mdl-37956201

ABSTRACT

Intact protein mass spectrometry (MS) coupled with liquid chromatography was applied to characterize the pharmacokinetics and stability profiles of therapeutic proteins. However, limitations from chromatography, including throughput and carryover, result in challenges with handling large sample numbers. Here, we combined intact protein MS with multiple front-end separations, including affinity capture, SampleStream, and high-field asymmetric waveform ion mobility spectrometry (FAIMS), to perform high-throughput and specific mass measurements of a multivalent antibody with one antigen-binding fragment (Fab) fused to an immunoglobulin G1 (IgG1) antibody. Generic affinity capture ensures the retention of both intact species 1Fab-IgG1 and the tentative degradation product IgG1. Subsequently, the analytes were directly loaded into SampleStream, where each injection occurs within ∼30 s. By separating ions prior to MS detection, FAIMS further offered improvement in signal-overnoise by ∼30% for denatured protein MS via employing compensation voltages that were optimized for different antibody species. When enhanced FAIMS transmission of 1Fab-IgG1 was employed, a qualified assay was established for spiked-in serum samples between 0.1 and 25 µg/mL, resulting in ∼10% accuracy bias and precision coefficient of variation. Selective FAIMS transmission of IgG1 as the degradation surrogate product enabled more sensitive detection of clipped species for intact 1Fab-IgG1 at 5 µg/mL in serum, generating an assay to measure 1Fab-IgG1 truncation between 2.5 and 50% with accuracy and precision below 20% bias and coefficient of variation. Our results revealed that the SampleStream-FAIMS-MS platform affords high throughput, selectivity, and sensitivity for characterizing therapeutic antibodies from complex biomatrices qualitatively and quantitatively.


Subject(s)
Immunoglobulin G , Ion Mobility Spectrometry , Ion Mobility Spectrometry/methods , Mass Spectrometry/methods , Chromatography, Liquid , Ions/chemistry
14.
Eur J Immunol ; 52(4): 541-549, 2022 04.
Article in English | MEDLINE | ID: mdl-35253907

ABSTRACT

Cytotoxic CD8+ T cells are a key element of the adaptative immune system to protect the organism against infections and malignant cells. During their activation and response, T cells undergo different metabolic pathways to support their energetic needs according to their localization and function. However, it has also been recently appreciated that this metabolic reprogramming also directly supports T-cell lineage differentiation. Accordingly, metabolic deficiencies and prolonged stress exposure can impact T-cell differentiation and skew them into an exhausted state. Here, we review how metabolism defines CD8+ T-cell differentiation and function. Moreover, we cover the principal metabolic dysregulation that promotes the exhausted phenotype under tumor or chronic virus conditions. Finally, we summarize recent strategies to reprogram impaired metabolic pathways to promote CD8+ T-cell effector function and survival.


Subject(s)
CD8-Positive T-Lymphocytes , Lymphocyte Activation , Cell Differentiation , Lymphocyte Count , T-Lymphocytes, Cytotoxic
15.
Nat Immunol ; 12(1): 62-9, 2011 Jan.
Article in English | MEDLINE | ID: mdl-21113164

ABSTRACT

The cytidine deaminase AID hypermutates immunoglobulin genes but can also target oncogenes, leading to tumorigenesis. The extent of AID's promiscuity and its predilection for immunoglobulin genes are unknown. We report here that AID interacted broadly with promoter-proximal sequences associated with stalled polymerases and chromatin-activating marks. In contrast, genomic occupancy of replication protein A (RPA), an AID cofactor, was restricted to immunoglobulin genes. The recruitment of RPA to the immunoglobulin loci was facilitated by phosphorylation of AID at Ser38 and Thr140. We propose that stalled polymerases recruit AID, thereby resulting in low frequencies of hypermutation across the B cell genome. Efficient hypermutation and switch recombination required AID phosphorylation and correlated with recruitment of RPA. Our findings provide a rationale for the oncogenic role of AID in B cell malignancy.


Subject(s)
B-Lymphocytes/metabolism , Cell Transformation, Neoplastic , Cytidine Deaminase/metabolism , Genes, Immunoglobulin , Replication Protein A/metabolism , Animals , B-Lymphocytes/immunology , B-Lymphocytes/pathology , Cell Transformation, Neoplastic/genetics , Cell Transformation, Neoplastic/immunology , Cells, Cultured , Chromatin Assembly and Disassembly/genetics , Cytidine Deaminase/genetics , Genes, Immunoglobulin/genetics , Genes, myc/genetics , High-Throughput Nucleotide Sequencing , Immunoglobulin Class Switching , Interleukin-4/immunology , Interleukin-4/metabolism , Lipopolysaccharides/immunology , Lipopolysaccharides/metabolism , Mice , Mice, Inbred C57BL , Mice, Knockout , Promoter Regions, Genetic/genetics , Replication Protein A/genetics , Somatic Hypermutation, Immunoglobulin
16.
Ann Surg Oncol ; 30(9): 5856-5865, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37227576

ABSTRACT

BACKGROUND: Esophageal squamous cell carcinoma has a high mortality rate in China. The metastatic pattern in the lymph nodes and the value of their dissection on the overall survival of these patients remain controversial. The primary aim of this study was to provide a basis for accurate staging of esophageal cancer and to identify the relationship between esophageal cancer surgery, lymph node dissection, and overall survival rates. METHODS: We utilized our hospital database to retrospectively review the data of 1727 patients with esophageal cancer who underwent R0 esophagectomy from January 2010 to December 2017. The lymph nodes were defined according to Japanese Classification of Esophageal Cancer, 11th Edition. The Efficacy Index (EI) was calculated by multiplying the frequency (%) of metastases to a zone and the 5-year survival rate (%) of patients with metastases to that zone, and then dividing by 100. RESULTS: The EI was high in the supraclavicular and mediastinal zones in patients with upper esophageal tumors, and the EI of 101R was 17.39, which was the highest among the lymph node stations. In patients with middle esophageal tumors, the EI was highest in the mediastinal zone, followed by the celiac and supraclavicular zones. Furthermore, the EI was highest in the celiac zone, followed by the mediastinal zones in patients with lower esophageal tumors. CONCLUSIONS: The EI of resected lymph nodes was found to vary between stations and was related to the primary location of the tumor.


Subject(s)
Carcinoma, Squamous Cell , Esophageal Neoplasms , Esophageal Squamous Cell Carcinoma , Humans , Esophageal Squamous Cell Carcinoma/surgery , Esophageal Squamous Cell Carcinoma/pathology , Retrospective Studies , Esophageal Neoplasms/pathology , Carcinoma, Squamous Cell/pathology , Lymphatic Metastasis/pathology , Neoplasm Staging , Lymph Node Excision , Lymph Nodes/surgery , Lymph Nodes/pathology , Survival Rate , Esophagectomy
17.
Opt Express ; 31(14): 23214-23228, 2023 Jul 03.
Article in English | MEDLINE | ID: mdl-37475412

ABSTRACT

Electromagnetic scattering in moving structures is a fundamental topic in physics and engineering. Yet no general numerical solution to related problems has been reported to date. We introduce here a generalized FDTD scheme to remedy this deficiency. That scheme is an extension of the FDTD standard Yee cell and stencil that includes not only the usual, physical fields but also auxiliary, unphysical fields allowing a straightforward application of moving boundary conditions. The proposed scheme is illustrated by four examples - a moving interface, a moving slab, a moving crystal and a moving gradient - with systematic validation against exact solutions.

18.
Drug Metab Dispos ; 51(12): 1628-1641, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37684055

ABSTRACT

The hepatic SLC13A5/SLC25A1-ATP-dependent citrate lyase (ACLY) signaling pathway, responsible for maintaining the citrate homeostasis, plays a crucial role in the pathogenesis of non-alcoholic fatty liver disease (NAFLD). Bempedoic acid (BA), an ACLY inhibitor commonly used for managing hypercholesterolemia, has shown promising results in addressing hepatic steatosis. This study aimed to elucidate the intricate relationships in processes of hepatic lipogenesis among SLC13A5, SLC25A1, and ACLY and to examine the therapeutic potential of BA in NAFLD, providing insights into its underlying mechanism. In murine primary hepatocytes and HepG2 cells, the silencing or pharmacological inhibition of SLC25A1/ACLY resulted in significant upregulation of SLC13A5 transcription and activity. This increase in SLC13A5 activity subsequently led to enhanced lipogenesis, indicating a compensatory role of SLC13A5 when the SLC25A1/ACLY pathway was inhibited. However, BA effectively counteracted this upregulation, reduced lipid accumulation, and ameliorated various biomarkers of NAFLD. The disease-modifying effects of BA were further confirmed in NAFLD mice. Mechanistic investigations revealed that BA could reverse the elevated transcription levels of SLC13A5 and ACLY, and the subsequent lipogenesis induced by PXR activation in vitro and in vivo. Importantly, this effect was diminished when PXR was knocked down, suggesting the involvement of the hepatic PXR-SLC13A5/ACLY signaling axis in the mechanism of BA action. In conclusion, SLC13A5-mediated extracellular citrate influx emerges as an alternative pathway to SLC25A1/ACLY in the regulation of lipogenesis in hepatocytes, BA exhibits therapeutic potential in NAFLD by suppressing the hepatic PXR-SLC13A5/ACLY signaling axis, while PXR, a key regulator in drug metabolism may be involved in the pathogenesis of NAFLD. SIGNIFICANCE STATEMENT: This work describes that bempedoic acid, an ATP-dependent citrate lyase (ACLY) inhibitor, ameliorates hepatic lipid accumulation and various hallmarks of non-alcoholic fatty liver disease. Suppression of hepatic SLC25A1-ACLY pathway upregulates SLC13A5 transcription, which in turn activates extracellular citrate influx and the subsequent DNL. Whereas in hepatocytes or the liver tissue challenged with high energy intake, bempedoic acid reverses compensatory activation of SLC13A5 via modulating the hepatic PXR-SLC13A5/ACLY axis, thereby simultaneously downregulating SLC13A5 and ACLY.


Subject(s)
Non-alcoholic Fatty Liver Disease , Mice , Animals , Non-alcoholic Fatty Liver Disease/metabolism , ATP Citrate (pro-S)-Lyase/metabolism , Liver/metabolism , Fatty Acids/metabolism , Signal Transduction , Citrates/metabolism , Citric Acid/metabolism
19.
Opt Lett ; 48(16): 4253-4256, 2023 Aug 15.
Article in English | MEDLINE | ID: mdl-37582005

ABSTRACT

This paper presents a space-time-wise orthogonal analysis of space-time crystals. This analysis provides a solution consisting of a pair of explicit parametric equations that result from a separate application of the Bloch-Floquet theorem in the (orthogonal) directions of space and time. Compared with previous approaches, this solution offers the benefits of greater simplicity, clearer emphasis on space-time duality, and deeper physical insight.

20.
Scand J Gastroenterol ; 58(1): 38-44, 2023 01.
Article in English | MEDLINE | ID: mdl-35850581

ABSTRACT

OBJECTIVES: Limited literature exists on the characteristics of early gastric signet ring cell carcinoma (GSRCC) within 20 mm. This study aimed to explore this type of cancer from several aspects, to provide guidance for early detection and intervention of GSRCC. METHODS: We retrospectively collected data from 24 patients diagnosed with early GSRCC ≤20 mm in Beijing Friendship Hospital from 2016 to 2021. According to tumor size, those lesions were divided into three groups: diminutive group (1-5 mm, n = 4), small group (6-10 mm, n = 12) and intermediate group (11-20 mm, n = 8). The clinicopathologic and endoscopic characteristics of GSRCC were compared among the three groups. RESULTS: Treatment strategies for lesions differed according to the size (p<.05). There were no significant differences among the three groups with regard to age, sex, Helicobacter pylori infection, tumor location and macroscopic type. Lesions were often flat type and more likely to present with discoloration, uneven color, ulceration and submucosal invasion with the increase of diameter. Almost all cases showed abnormal intervening part (IP) under magnifying endoscopy. CONCLUSIONS: The location of early signet ring cell carcinoma is not specific, and the diminutive lesions are often flat. Abnormal IP may be the early endoscopic feature of early GSRCC.


Subject(s)
Carcinoma, Signet Ring Cell , Helicobacter Infections , Helicobacter pylori , Stomach Neoplasms , Humans , Retrospective Studies , Early Detection of Cancer , Carcinoma, Signet Ring Cell/diagnosis , Carcinoma, Signet Ring Cell/pathology , Stomach Neoplasms/pathology , Endoscopy, Gastrointestinal
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