The emerging mechanisms and functions of microautophagy.

'Autophagy' refers to an evolutionarily conserved process through which cellular contents, such as damaged organelles and protein aggregates, are delivered to lysosomes for degradation. Different forms of autophagy have been described on the basis of the nature of the cargoes and the means used to deliver them to lysosomes. At present, the prevailing categories of autophagy in mammalian cells are macroautophagy, microautophagy and chaperone-mediated autophagy. The molecular mechanisms and biological functions of macroautophagy and chaperone-mediated autophagy have been extensively studied, but microautophagy has received much less attention. In recent years, there has been a growth in research on microautophagy, first in yeast and then in mammalian cells. Here we review this form of autophagy, focusing on selective forms of microautophagy. We also discuss the upstream regulatory mechanisms, the crosstalk between macroautophagy and microautophagy, and the functional implications of microautophagy in diseases such as cancer and neurodegenerative disorders in humans. Future research into microautophagy will provide opportunities to develop novel interventional strategies for autophagy- and lysosome-related diseases.

STING directly recruits WIPI2 for autophagosome formation during STING-induced autophagy.

The cGAS-STING pathway plays an important role in host defense by sensing pathogen DNA, inducing type I IFNs, and initiating autophagy. However, the molecular mechanism of autophagosome formation in cGAS-STING pathway-induced autophagy is still unclear. Here, we report that STING directly interacts with WIPI2, which is the key protein for LC3 lipidation in autophagy. Binding to WIPI2 is necessary for STING-induced autophagosome formation but does not affect STING activation and intracellular trafficking. In addition, the specific interaction between STING and the PI3P-binding motif of WIPI2 leads to the competition of WIPI2 binding between STING and PI3P, and mutual inhibition between STING-induced autophagy and canonical PI3P-dependent autophagy. Furthermore, we show that the STING-WIPI2 interaction is required for the clearance of cytoplasmic DNA and the attenuation of cGAS-STING signaling. Thus, the direct interaction between STING and WIPI2 enables STING to bypass the canonical upstream machinery to induce LC3 lipidation and autophagosome formation.

FBP1 inhibits NSCLC stemness by promoting ubiquitination of Notch1 intracellular domain and accelerating degradation.

The existence of cancer stem cells is widely acknowledged as the underlying cause for the challenging curability and high relapse rates observed in various tumor types, including non-small cell lung cancer (NSCLC). Despite extensive research on numerous therapeutic targets for NSCLC treatment, the strategies to effectively combat NSCLC stemness and achieve a definitive cure are still not well defined. The primary objective of this study was to examine the underlying mechanism through which Fructose-1,6-bisphosphatase 1 (FBP1), a gluconeogenic enzyme, functions as a tumor suppressor to regulate the stemness of NSCLC. Herein, we showed that overexpression of FBP1 led to a decrease in the proportion of CD133-positive cells, weakened tumorigenicity, and decreased expression of stemness factors. FBP1 inhibited the activation of Notch signaling, while it had no impact on the transcription level of Notch 1 intracellular domain (NICD1). Instead, FBP1 interacted with NICD1 and the E3 ubiquitin ligase FBXW7 to facilitate the degradation of NICD1 through the ubiquitin-proteasome pathway, which is independent of the metabolic enzymatic activity of FBP1. The aforementioned studies suggest that targeting the FBP1-FBXW7-NICD1 axis holds promise as a therapeutic approach for addressing the challenges of NSCLC recurrence and drug resistance.

Post-translational Modifications of Key Machinery in the Control of Mitophagy.

Mitophagy refers to the process of selective removal of damaged or superfluous mitochondria via the autophagy/lysosome pathway. In the past decade the molecular mechanisms underlying mitophagy have been extensively studied. It is now well established that the key mitophagy machinery undergoes extensive post-translational modifications (PTMs) such as phosphorylation/dephosphorylation, ubiquitination/deubiquitination, and acetylation/deacetylation that involve an array of enzymes including protein kinases/phosphatases, E3 ligases/deubiquitinases, acetyltransferases/deacetylases. In this review we provide a systematic summary of these key PTMs, and discuss the effectors and the functional implications of such PTMs in mitophagy-related diseases. Understanding PTM of the mitophagy machinery offers a unique window of opportunity for the discovery of novel mitophagy interventional strategies and for the control of mitophagy-related diseases.

A New and Practical Model of Human-like Ascending Aorta Aneurysm in Rats.

INTRODUCTION: Ascending aortic aneurysm is a serious health risk. In order to study ascending aortic aneurysms, elastase and calcium ion treatment for aneurysm formation are mainly used, but their aneurysm formation time is long, the aneurysm formation rate is low. Thus, this study aimed to construct a rat model of ascending aorta aneurysm with a short modeling time and high aneurysm formation rate, which may mimic the pathological processes of human ascending aorta aneurysm. METHODS: Cushion needles with different pipe diameters (1.0, 1.2, 1.4 and 1.6 mm) were used to establish a human-like rat model of ascending aortic aneurysm by narrowing the ascending aorta of rats and increasing the force of blood flow on the vessel wall. The vascular diameters were evaluated using color Doppler ultrasonography after two weeks. The characteristics of ascending aortic aneurysm in rats were detected by Masson's trichrome staining, Verhoeff's Van Gieson staining and hematoxylin and eosin staining while RT-PCR were utilized to assess the total RNA of cytokine interleukin-1ß, interleukin 6, transforming growth factor-beta1 and metalloproteinase 2. RESULTS: Two weeks after surgery, the ultrasound images and the statistical analysis demonstrated that the diameter of the ascending aorta in rats increased more than 1.5 times, similar to that in humans, indicating the success of animal modeling of ascending aortic aneurysm. Moreover, the optimal constriction diameter of the ascending aortic aneurysm model is 1.4 mm by the statistical analysis of the rate of ascending aortic aneurysm and mortality rate in rats with different constriction diameters. CONCLUSIONS: The human-like ascending aortic aneurysm model developed in this study can be used for the studies of the pathological processes and mechanisms in ascending aortic aneurysm in a more clinically relevant fashion.

Cancer-associated fibroblasts contribute to the immunosuppressive landscape and influence the efficacy of the combination therapy of PD-1 inhibitors and antiangiogenic agents in hepatocellular carcinoma.

BACKGROUND: Chronic inflammation is considered the most critical predisposing factor of hepatocellular carcinoma (HCC), with inflammatory cell heterogeneity, hepatic fibrosis accumulation, and abnormal vascular proliferation as prominent features of the HCC tumor microenvironment (TME). Cancer-associated fibroblasts (CAFs) play a key role in HCC TME remodeling. Therefore, the level of abundance of CAFs may significantly affect the prognosis and outcome in HCC patients. METHODS: Unsupervised clustering was performed based on 39 genes related to CAFs in HCC identified by single-cell RNA sequencing data. Patients of bulk RNA were grouped into CAF low abundance cluster and high abundance clusters. Subsequently, prognosis, immune infiltration landscape, metabolism, and treatment response between the two clusters were investigated and validated by immunohistochemistry. RESULTS: Patients in the CAF high cluster had a higher level of inflammatory cell infiltration, a more significant immunosuppressive microenvironment, and a significantly worse prognosis than those in the low cluster. At the metabolic level, the CAF high cluster had lower levels of aerobic oxidation and higher angiogenic scores. Drug treatment response prediction indicated that the CAF high cluster could have a better response to PD-1 inhibitors and conventional chemotherapeutic agents for HCC such as anti-angiogenic drugs, whereas CAF low cluster may be more sensitive to transarterial chemoembolization treatment. CONCLUSIONS: This study not only revealed the TME characteristics of HCC with the difference in CAF abundance but also further confirmed that the combination therapy of PD-1 inhibitors and anti-angiogenic drugs may be more valuable for patients with high CAF abundance.

Landscape of molecular crosstalk between SARS-CoV-2 infection and cardiovascular diseases: emphasis on mitochondrial dysfunction and immune-inflammation.

BACKGROUND: SARS-CoV-2, the pathogen of COVID-19, is a worldwide threat to human health and causes a long-term burden on the cardiovascular system. Individuals with pre-existing cardiovascular diseases are at higher risk for SARS-CoV-2 infection and tend to have a worse prognosis. However, the relevance and pathogenic mechanisms between COVID-19 and cardiovascular diseases are not yet completely comprehended. METHODS: Common differentially expressed genes (DEGs) were obtained in datasets of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) infected with SARS-CoV-2 and myocardial tissues from heart failure patients. Further GO and KEGG pathway analysis, protein-protein interaction (PPI) network construction, hub genes identification, immune microenvironment analysis, and drug candidate predication were performed. Then, an isoproterenol-stimulated myocardial hypertrophy cell model and a transverse aortic constriction-induced mouse heart failure model were employed to validate the expression of hub genes. RESULTS: A total of 315 up-regulated and 78 down-regulated common DEGs were identified. Functional enrichment analysis revealed mitochondrial metabolic disorders and extensive immune inflammation as the most prominent shared features of COVID-19 and cardiovascular diseases. Then, hub DEGs, as well as hub immune-related and mitochondria-related DEGs, were screened. Additionally, nine potential therapeutic agents for COVID-19-related cardiovascular diseases were proposed. Furthermore, the expression patterns of most of the hub genes related to cardiovascular diseases in the validation dataset along with cellular and mouse myocardial damage models, were consistent with the findings of bioinformatics analysis. CONCLUSIONS: The study unveiled the molecular networks and signaling pathways connecting COVID-19 and cardiovascular diseases, which may provide novel targets for intervention of COVID-19-related cardiovascular diseases.

A simple and available measurement of onco-sEV dsDNA to protein ratio as a potential tumor marker.

BACKGROUND: Small extracellular vesicles (sEVs) have great potential as new biomarkers in liquid biopsy. However, due to the limitations of sEVs extraction and component analysis procedures, further clinical applications of sEVs are hampered. Carcinoembryonic antigen (CEA) is a commonly used broad-spectrum tumor marker that is strongly expressed in a variety of malignancies. RESULTS: In this study, CEA+ sEVs were directly separated from serum using immunomagnetic beads, and the nucleic acid to protein ultraviolet absorption ratio (NPr) of CEA+ sEVs was determined. It was found that the NPr of CEA+ sEVs in tumor group was higher than that of healthy group. We further analyzed the sEV-derived nucleic acid components using fluorescent staining and found that the concentration ratio of double-stranded DNA to protein (dsDPr) in CEA+ sEVs was also significantly different between the two groups, with a sensitivity of 100% and a specificity of 41.67% for the diagnosis of pan-cancer. The AUC of dsDPr combined with NPr was 0.87 and the ACU of dsDPr combined with CA242 could reach 0.94, showing good diagnostic performance for pan-cancer. CONCLUSIONS: This study demonstrates that the dsDPr of CEA+ sEVs can effectively distinguish sEVs derived from tumor patients and healthy individuals, which can be employed as a simple and cost-effective non-invasive screening technology to assist tumor diagnosis.

Chemical mitophagy modulators: Drug development strategies and novel regulatory mechanisms.

Maintaining mitochondrial homeostasis is a potential therapeutic strategy for various diseases, including neurodegenerative diseases, cardiovascular diseases, metabolic disorders, and cancer. Selective degradation of mitochondria by autophagy (mitophagy) is a fundamental mitochondrial quality control mechanism conserved from yeast to humans. Indeed, small-molecule modulators of mitophagy are valuable pharmaceutical tools that can be used to dissect complex biological processes and turn them into potential drugs. In the past few years, pharmacological regulation of mitophagy has shown promising therapeutic efficacy in various disease models. However, with the increasing number of chemical mitophagy modulator studies, frequent methodological flaws can be observed, leading some studies to draw unreliable or misleading conclusions. This review attempts (a) to summarize the molecular mechanisms of mitophagy; (b) to propose a Mitophagy Modulator Characterization System (MMCS); (c) to perform a comprehensive analysis of methods used to characterize mitophagy modulators, covering publications over the past 20 years; (d) to provide novel targets for pharmacological intervention of mitophagy. We believe this review will provide a panorama of current research on chemical mitophagy modulators and promote the development of safe and robust mitophagy modulators with therapeutic potential by introducing high methodological standards.

CircRNA CDR1as: a novel diagnostic and prognostic biomarker for gastric cancer.

BACKGROUND: Circular RNA (circRNA) CDR1as is emerging as a vital tumour regulator. This study aimed to investigate its diagnostic and prognostic value and molecular mechanisms for gastric cancer (GC). METHODS: CDR1as expression in GC and adjacent normal tissues (n = 82), paired plasma (n = 65) and plasma exosome samples (n = 68) from GC patients and healthy controls were determined by reverse transcription quantitative polymerase chain reaction (RT-qPCR). Correlations between CDR1as level and clinicopathological factors of GC patients were analysed. Its diagnostic and prognostic value was evaluated by receiver operating characteristic (ROC) curves and Cox regression analysis combined with Kaplan-Meier plots. CDR1as-regulated proteins and signalling pathways were identified by quantitative proteomics and bioinformatic analysis. RESULTS: CDR1as was downregulated in GC tissues and associated with tumour size and neural invasion. Plasma- and exosome-derived CDR1as was upregulated in GC patients while plasma-derived CDR1as level was related to lymphatic metastasis. Area under ROC curve (AUC) of tissue-, plasma- and exosome-derived CDR1as was 0.782, 0.641, 0.536 while combination of plasma CDR1as, serum CEA and CA19-9 increased AUC to 0.786. Distal metastasis, TNM stage and tissue-derived CDR1as level were independent predictors for overall survival (OS) of patients. MiRNA signalling networks and glycine, serine and threonine metabolism were regulated by CDR1as and HSPE1 might be a key protein. CONCLUSIONS: CDR1as is a crucial regulator and promising biomarker for GC diagnosis and prognosis.

CDR1as level in tumour tissues and plasma of GC patients was associated with tumour progression. The findings indicate that CDR1as is involved in GC progression and is a potential diagnostic and prognostic biomarker.

The distribution characteristics of global blaOXA-carrying Klebsiella pneumoniae.

OBJECTIVE: To analyze the distribution of blaOXA among global Klebsiella pneumoniae and the characteristics of blaOXA-carrying K. pneumoniae. MATERIALS AND METHODS: The genomes of global K. pneumoniae were downloaded from NCBI by Aspera software. After quality check, the distribution of blaOXA among the qualified genomes was investigated by annotation with the resistant determinant database. The phylogenetic tree was constructed for the blaOXA variants based on the single nucleotide polymorphism (SNP) to explore the evolutionary relationship between these variants. The MLST (multi-locus sequence type) website and blastn tools were utilized to determine the sequence types (STs) of these blaOXA-carrying strains. and sample resource, isolation country, date and host were extracted by perl program for analyzing the characteristics of these strains. RESULTS: A total of 12,356 K. pneumoniae genomes were downloaded and 11,429 ones were qualified. Among them, 4386 strains were found to carry 5610 blaOXA variants which belonged to 27 varieties of blaOXAs, blaOXA-1 (n = 2891, 51.5%) and blaOXA-9 (n = 969, 17.3%) were the most prevalent blaOXA variants, followed by blaOXA-48 (n = 800, 14.3%) and blaOXA-232 (n = 480, 8.6%). The phylogenetic tree displayed 8 clades, three of them were composed of carbapenem-hydrolyzing oxacillinase (CHO). Totally, 300 distinct STs were identified among 4386 strains with ST11 (n = 477, 10.9%) being the most predominant one followed by ST258 (n = 410, 9.4%). Homo sapiens (2696/4386, 61.5%) was the main host for blaOXA-carrying K. pneumoniae isolates. The blaOXA-9-carrying K. pneumoniae strains were mostly found in the United States and blaOXA-48-carrying K. pneumoniae strains were mainly distributed in Europe and Asia. CONCLUSION: Among the global K. pneumoniae, numerous blaOXA variants were identified with blaOXA-1, blaOXA-9, blaOXA-48 and blaOXA-232 being the most prevalent ones, indicating that blaOXA rapidly evolved under the selective pressure of antimicrobial agents. ST11 and ST258 were the main clones for blaOXA-carrying K. pneumoniae.

AMPK-Dependent Phosphorylation of GAPDH Triggers Sirt1 Activation and Is Necessary for Autophagy upon Glucose Starvation.

Eukaryotes initiate autophagy to cope with the lack of external nutrients, which requires the activation of the nicotinamide adenine dinucleotide (NAD(+))-dependent deacetylase Sirtuin 1 (Sirt1). However, the mechanisms underlying the starvation-induced Sirt1 activation for autophagy initiation remain unclear. Here, we demonstrate that glyceraldehyde 3-phosphate dehydrogenase (GAPDH), a conventional glycolytic enzyme, is a critical mediator of AMP-activated protein kinase (AMPK)-driven Sirt1 activation. Under glucose starvation, but not amino acid starvation, cytoplasmic GAPDH is phosphorylated on Ser122 by activated AMPK. This causes GAPDH to redistribute into the nucleus. Inside the nucleus, GAPDH interacts directly with Sirt1, displacing Sirt1's repressor and causing Sirt1 to become activated. Preventing this shift of GAPDH abolishes Sirt1 activation and autophagy, while enhancing it, through overexpression of nuclear-localized GAPDH, increases Sirt1 activation and autophagy. GAPDH is thus a pivotal and central regulator of autophagy under glucose deficiency, undergoing AMPK-dependent phosphorylation and nuclear translocation to activate Sirt1 deacetylase activity.

TRANSSCLERAL INCISION FOR PEELING SUBRETINAL PROLIFERATION TISSUE IN GRADE C PROLIFERATIVE VITREORETINOPATHY.

PURPOSE: The purpose of this study was to investigate the clinical outcomes of an optimized method to clearly remove the subretinal proliferative tissue by transscleral puncture into the subretinal space in patients with grade C proliferative vitreoretinopathy without inducing retinal injury. METHODS: This was a prospective clinical observation study. Eight consecutive patients who had undergone optimized vitrectomy surgery for retinal detachment complicated by grade C proliferative vitreoretinopathy were investigated. Subretinal proliferation was cleared by adding one additional scleral 23-gauge trocar under the detached retina at 9 mm to 10 mm from the limbus. After the sclera is pierced, the puncture knife changed its direction without touching the retina. 23-G intraocular forceps were used to remove the proliferation strand or membrane through the puncture channel. RESULTS: Retinal reattachment was achieved in each case without a retinotomy. The mean best-corrected visual acuity was improved within the first 1 month ( P = 0.039) and remained stable at the following phase. There were no postoperative complications, such as reoccurrence of retinal detachment or proliferative vitreoretinopathy. No postoperative hemorrhage or hypotension was observed. CONCLUSION: The satisfying results demonstrated the feasibility of this cost-effective, easy-to-follow, transscleral vitrectomy method in treating retinal detachment with grade C proliferative vitreoretinopathy.

HOXB13 facilitates hepatocellular carcinoma progression by activating AKT/mTOR signaling pathway.

INTRODUCTION AND OBJECTIVES: Hepatocellular carcinoma (HCC) is one of the sixth most common malignancies worldwide and is accompanied by high mortality. Homeobox B13 (HOXB13) has been shown to be involved in the development of various cancers. This study aimed to investigate the role of HOXB13 in HCC progression. MATERIALS AND METHODS: The expression of HOXB13 in HCC tumor tissues was analyzed using qRT-PCR and immunohistochemical staining . After overexpression or downregulation of HOXB13 in HCC cell lines, cell proliferation was detected by CCK8 assay and Ki67 staining and cell invasion ability were tested by transwell assay. Western blot assay was applied to analyze the effect of HOXB13 on related signaling pathways. In addition, the role of HOXB13 on HCC in vivo was explored using a HCC mouse model. IF and WB were performed to detect cell proliferation, apoptosis and related protein expression in mice tumor tissues. RESULTS: The results showed that the expression of HOXB13 was significantly increased in HCC tissues compared with adjacent tissues and positively correlated with the tumor stage and survival of HCC patients. Overexpression of HOXB13 promoted the proliferation and invasion of HCC cells and up-regulated the protein expression of AKT, mTOR and MMP2. In contrast, the downregulation of HOXB13 resulted in the opposite results. In vivo experiments, HOXB13 significantly promoted tumor growth in mice bearing HCC by promoting cell proliferation and inhibiting cell apoptosis. CONCLUSIONS: This study suggested that HOXB13 can facilitate HCC progression by activation of the AKT/mTOR signaling pathway. HOXB13 may be a novel target for HCC therapy.

Low dose PFDA induces DNA damage and DNA repair inhibition by promoting nuclear cGAS accumulation in ovarian epithelial cells.

Per- and polyfluoroalkyl substances (PFAS), the versatile anthropogenic chemicals, are popular with the markets and manufactured in large quantities yearly. Accumulation of PFAS has various adverse health effects on human. Albeit certain members of PFAS were found to have genotoxicity in previous studies, the mechanisms underlying their effects on DNA damage repair remain unclear. Here, we investigated the effects of Perfluorodecanoic acid (PFDA) on DNA damage and DNA damage repair in ovarian epithelial cells through a series of in vivo and in vitro experiments. At environmentally relevant concentration, we firstly found that PFDA can cause DNA damage in primary mouse ovarian epithelial cells and IOSE-80 cells. Moreover, nuclear cGAS increased in PFDA-treated cells, which leaded to the efficiency of DNA homologous recombination (HR) decreased and DNA double-strand breaks perpetuated. In vivo experiments also verified that PFDA can induce more DNA double-strand breaks lesions and nuclear cGAS in ovarian tissue. Taken together, our results unveiled that low dose PFDA can cause deleterious effects on DNA and DNA damage repair (DDR) in ovarian epithelial cells and induce genomic instability.

Construction of a Matrix Cancer-Associated Fibroblast Signature Gene-Based Risk Prognostic Signature for Directing Immunotherapy in Patients with Breast Cancer Using Single-Cell Analysis and Machine Learning.

Cancer-associated fibroblasts (CAFs) are heterogeneous constituents of the tumor microenvironment involved in the tumorigenesis, progression, and therapeutic responses of tumors. This study identified four distinct CAF subtypes of breast cancer (BRCA) using single-cell RNA sequencing (RNA-seq) data. Of these, matrix CAFs (mCAFs) were significantly associated with tumor matrix remodeling and strongly correlated with the transforming growth factor (TGF)-ß signaling pathway. Consensus clustering of The Cancer Genome Atlas (TCGA) BRCA dataset using mCAF single-cell characteristic gene signatures segregated samples into high-fibrotic and low-fibrotic groups. Patients in the high-fibrotic group exhibited a significantly poor prognosis. A weighted gene co-expression network analysis and univariate Cox analysis of bulk RNA-seq data revealed 17 differential genes with prognostic values. The mCAF risk prognosis signature (mRPS) was developed using 10 machine learning algorithms. The clinical outcome predictive accuracy of the mRPS was higher than that of the conventional TNM staging system. mRPS was correlated with the infiltration level of anti-tumor effector immune cells. Based on consensus prognostic genes, BRCA samples were classified into the following two subtypes using six machine learning algorithms (accuracy > 90%): interferon (IFN)-γ-dominant (immune C2) and TGF-ß-dominant (immune C6) subtypes. Patients with mRPS downregulation were associated with improved prognosis, suggesting that they can potentially benefit from immunotherapy. Thus, the mRPS model can stably predict BRCA prognosis, reflect the local immune status of the tumor, and aid clinical decisions on tumor immunotherapy.

Gradient Graphdiyne Induced Copper and Oxygen Vacancies in Cu0.95 V2 O5 Anodes for Fast-Charging Lithium-Ion Batteries.

Vacancies can significantly affect the performance of metal oxide materials. Here, a gradient graphdiyne (GDY) induced Cu/O-dual-vacancies abundant Cu0.95 V2 O5 @GDY heterostructure material has been prepared as a competitive fast-charging anode material. Cu0.95 V2 O5 self-catalyzes the growth of gradient GDY with rich alkyne-alkene complex in the inner layer and rich alkyne bonds in the outer layer, leading to the formation of Cu and O vacancies in Cu0.95 V2 O5 . The synergistic effect of vacancies and gradient GDY results in the electron redistribution at the hetero-interface to drive the generation of a built-in electric field. Thus, the Li-ion transport kinetics, electrochemical reaction reversibility and Li storage sites of Cu0.95 V2 O5 are greatly enhanced. The Cu0.95 V2 O5 @GDY anodes show excellent fast-charging performance with high capacities and negligible capacity decay for 10 000 cycles and 20 000 cycles at extremely high current densities of 5 A g-1 and 10 A g-1 , respectively. Over 30 % of capacity can be delivered in 35 seconds.

O-GlcNAcylation promotes fatty acid synthase activity under nutritional stress as a pro-survival mechanism in cancer cells.

Protein O-GlcNAcylation is a specific form of protein glycosylation that targets a wide range of proteins with important functions. O-GlcNAcylation is known to be deregulated in cancer and has been linked to multiple aspects of cancer pathology. Despite its ubiquity and importance, the current understanding of the role of O-GlcNAcylation in the stress response remains limited. In this study, we performed a quantitative chemical proteomics-based open study of the O-GlcNAcome in HeLa cells, and identified 163 differentially-glycosylated proteins under starvation, involving multiple metabolic pathways. Among them, fatty acid metabolism was found to be targeted and subsequent analysis confirmed that fatty acid synthase (FASN) is O-GlcNAcylated. O-GlcNAcylation led to enhanced de novo fatty acid synthesis (FAS) activity, and fatty acids contributed to the cytoprotective effects of O-GlcNAcylation under starvation. Moreover, dual inhibition of O-GlcNAcylation and FASN displayed a strong synergistic effect in vitro in inducing cell death in cancer cells. Together, the results from this study provide novel insights into the role of O-GlcNAcylation in the nutritional stress response and suggest the potential of combining inhibition of O-GlcNAcylation and FAS in cancer therapy.

Increased serum adenosine deaminase activity in patients with adult-onset Still's disease.

BACKGROUND: Adult-onset Still's disease (AOSD) is a systemic inflammatory disease of unknown etiology, lacking specific diagnosis and disease activity evaluation indicators. This study will analyze the activity and clinical significance of Adenosine deaminase (ADA) in AOSD patients. METHODS: Totally 53 AOSD patients, 60 patients with other autoimmune diseases including systemic lupus erythematosus (SLE), sjogren syndrome (SS) and rheumatoid arthritis (RA), as well as 60 healthy subjects were included in this study. AOSD activity was determined by Pouchot score. We analyzed the correlation between ADA activity and clinical parameters. In addition, the correlation between ADA activity and disease activity score was also analyzed. RESULTS: This study showed that the activity of ADA in AOSD patients was significantly higher than that of healthy controls, SLE, SS and RA patient groups (p < 0.0001). The ADA activity of AOSD patients decreased significantly after systemic treatment (p < 0.0001). Correlation analysis showed that ADA activity was positively correlated with ALT(r = 0.54, p < 0.0001), AST (r = 0.82, p < 0.0001) and serum ferritin (r = 0.67, p < 0.001). ADA activity was negatively correlated with white blood cell (r = - 0.42, p = 0.002) and platelet counts (r = - 0.44, p = 0.001). We also found a significant positive correlation between the activity of ADA and Pouchot score in AOSD patients (r = 0.51, p = 0.001). Receiver operating characteristic (ROC) curve analysis showed that ADA activity had a sensitivity of 93.3%, and a specificity of 83% for the diagnosis of AOSD, with an area under the curve of 0.93. CONCLUSION: This study showed that serum ADA activity can be used as a potential biomarker for AOSD diagnosis and disease activity assessment.

A longitudinal study of humoral immune responses induced by a 3-dose inactivated COVID-19 vaccine in an observational, prospective cohort.

BACKGROUND: To determine the dynamic SARS-CoV-2 specific antibody levels induced by 3 doses of an inactivated COVID-19 vaccine, CoronaVac. An observational, prospective cohort study was performed with 93 healthy healthcare workers from a tertiary hospital in Nanjing, China. Serum SARS-CoV-2 specific IgM, IgG, and neutralizing antibodies (NAb) were measured at different time points among participants who received 3 doses of inactivated COVID-19 vaccine. RESULTS: 91.3% (85/93) and 100% (72/72) participants showed positive both for SARS-CoV-2 specific IgG and NAb after 2-dose CoronaVac and after 3-dose CoronaVac, respectively. Anti-SARS-CoV-2 IgG responses reached 91.21 (55.66-152.06) AU/mL, and surrogate NAb was 47.60 (25.96-100.81) IU/mL on day 14 after the second dose. Anti-SARS-CoV-2 IgG responses reached 218.29 (167.53-292.16) AU/mL and surrogate NAb was 445.54 (171.54-810.90) IU/mL on day 14 after the third dose. Additionally, SARS-CoV-2 specific surrogate neutralizing antibody titers were highly correlated with serum neutralization activities against Ancestral, Omicron, and Delta strains. Moreover, significantly higher SARS-CoV-2 IgG responses, but not NAb responses, were found in individuals with breakthrough infection when compared to that of 3-dose CoronaVac recipients. CONCLUSIONS: CoronaVac elicited robust SARS-CoV-2 specific humoral responses. Surrogate NAb assay might substitute for pseudovirus neutralization assay. Monitoring SARS-CoV-2 antibody responses induced by vaccination would provide important guidance for the optimization of COVID-19 vaccines.