👤 Junhui He

Colorectal carcinogenesis and progression are associated with aberrant alternative splicing, yet its molecular mechanisms remain largely unexplored. Here, we find that Microrchidia family CW-type zinc finger 2 (MORC2) binds to RRM1 domain of RNA binding motif protein 39 (RBM39), and RBM39 interacts with site 1 of pre-CDK5RAP2 exon 32 via its UHM domain, resulting in a splicing switch of cyclin-dependent kinase 5 regulatory subunit associated protein 2 (CDK5RAP2) L to CDK5RAP2 S. CDK5RAP2 S promotes invasion of colorectal cancer cells in vitro and metastasis in vivo. Mechanistically, CDK5RAP2 S specifically recruits the PHD finger protein 8 to promote Slug transcription by removing repressive histone marks at the Slug promoter. Moreover, CDK5RAP2 S, but not CDK5RAP2 L, is essential for the promotion of epithelial-mesenchymal transition induced by MORC2 or RBM39. Importantly, high protein levels of MORC2, RBM39 and Slug are strongly associated with metastasis and poor clinical outcomes of colorectal cancer patients. Taken together, our findings uncover a novel mechanism by which MORC2 promotes colorectal cancer metastasis, through RBM39-mediated pre-CDK5RAP2 alternative splicing and highlight the MORC2/RBM39/CDK5RAP2 axis as a potential therapeutic target for colorectal cancer. Show less

Endothelial-to-mesenchymal transition (EndMT) is a key driver of atherosclerosis. Aerobic glycolysis is increased in the endothelium of atheroprone areas, accompanied by elevated lactate levels. Histone lactylation, mediated by lactate, can regulate gene expression and participate in disease regulation. However, whether histone lactylation is involved in atherosclerosis remains unknown. Here, we report that lipid peroxidation could lead to EndMT-induced atherosclerosis by increasing lactate-dependent histone H3 lysine 18 lactylation (H3K18la) Show less

Acquired radio-resistance is thought to be one of the main causes of recurrent metastasis after failure of nasopharyngeal carcinoma (NPC) radiotherapy, which may be related to X-ray-induced epithelial-mesenchymal transition (EMT) activation. The circadian clock gene, BMAL1, has been shown to correlate with the sensitivity of NPCs to radiotherapy, but the specific mechanism has not been reported. NPC cells were irradiated by conventional fractionation to generate radiotherapy-resistant cells. NPC cells with BMAL1 gene stabilization/overexpression and interference were obtained by lentiviral transfection. Western blotting, colony formation analysis, cell counting kit-8 assays, wound-healing tests, Transwell assays, flow cytometry, the EDU method, nuclear plasma separation experiments, HE staining, immunohistochemical staining and TUNEL staining were performed to explore the influence and molecular mechanism of the circadian clock gene, BMAL1, on NPC-acquired radio-resistance and EMT through in vitro and in vivo experiments. The results indicated that there was a gradual downregulation of BMAL1 gene protein expression during the routine dose induction of radio-resistance in NPC cells. EMT activation was present in the radiation-resistant cell line 5-8FR, and was accompanied by the significant enhancement of proliferation, migration and invasion. The BMAL1 gene significantly increased the radiosensitivity of the radiation-resistant cell line 5-8FR and reversed the acquired radio-resistance of NPCs, which was accomplished by inhibiting the TGF-β1/Smads/Snail1 axis-mediated EMT. Show less

Aberrant mechanical forces were considered as an important factor for osteoarthritis (OA) pathogenesis. Plant homeodomain finger-containing protein 8 (PHF8) participated in osteogenic differentiation and inflammatory progression. However, the role of PHF8 in aberrant force-related OA remains to be elucidated. In this study, a fluid shear stress (FSS) model in ATDC5 cells and an anterior cruciate ligament transection (ACLT) animal model were constructed. The results revealed the decrease of PHF8 in aberrant force-induced cartilage damage in vitro and in vivo. PHF8 overexpression alleviated the aberrant force-induced cell apoptosis, extracellular matrix degradation, and inflammation. Chromatin immunoprecipitation (ChIP) assays demonstrated that PHF8 epigenetically regulated WWP2 expression through demethylating H3K9me2 at WWP2 promoter, which was influenced by FSS treatment. C-X-C chemokine receptor type 4 (CXCR4) was identified as a potential substrate of WWP2. Co-immunoprecipitation (Co-IP) and ubiquitination experiments further demonstrated WWP2 decreased the stability of CXCR4 via the ubiquitination pathway. Subsequently, rescue experiments validated reintroduction of WWP2 significantly attenuated the effects of PHF8 deletion on FSS-induced chondrocyte injury, and CXCR4 overexpression reversed the protective effects of WWP2 overexpression on chondrocyte injury in FSS-treated ATDC5 cells. Moreover, delivery of a PHF8 adeno-associated virus (AAV) into articular cartilage remarkably ameliorated the breakdown of cartilage matrix by ACLT in mice. In conclusion, our findings highlighted the importance of PHF8/WWP2/CXCR4 signaling pathway in aberrant force-induced cartilage injury, which might provide a novel insight on future epigenetic-based treatment of posttraumatic OA. Show less

Increasing evidence has indicated that long non-coding RNAs (lncRNAs) have been proven to regulate esophageal cancer progression. The lncRNA protein disulfide isomerase family A member 3 pseudogene 1 (PDIA3P1) has been shown to promote cancer stem cell properties; however, its mechanism of action remains unclear. In this study, we investigated the regulation of esophageal cancer stem cell properties by the interaction of PDIA3P1 with proteins. The GEPIA2 and Gene Expression Omnibus databases were used to analyze gene expression. PDIA3P1 expression in human esophageal squamous cell carcinoma (ESCC) tissues and cell lines was detected by quantitative real-time polymerase chain reaction (qRT-PCR). Loss-of-function experiments were performed to determine the effects of PDIA3P1 on ESCC cell proliferation, migration, and invasion. The sphere formation assay, number of side population cells, and CD271 + /CD44 + cells were detected by flow cytometry to identify the cancer stem cell properties. RNA immunoprecipitation (RIP), RNA pull-down, co-immunoprecipitation (co-IP), dual luciferase reporter, and cleavage under targets and tagmentation (CUT&Tag) assays were performed to elucidate the underlying molecular mechanisms. PDIA3P1 expression was upregulated in ESCC cell lines and tissues. Functionally, higher PDIA3P1 expression promoted cell proliferation, invasion, and metastasis and inhibited apoptosis in esophageal cancer. Importantly, PDIA3P1 promoted cancer stem cell properties in ESCC. Mechanistically, PDIA3P1 interacted with and stabilized octamer-binding transcription factor 4 (OCT4) by eliminating its ubiquitination by the ubiquitinating enzyme WW domain-containing protein 2 (WWP2). Moreover, as a transcription factor, OCT4 bound to the PDIA3P1 promoter and promoted its transcription. Our research revealed a novel mechanism by which a positive feedback loop exists between PDIA3P1 and OCT4. It also demonstrated that the PDIA3P1-WWP2-OCT4 loop is beneficial for promoting the cancer stem cell properties of ESCC. Owing to this regulatory relationship, the PDIA3P1-WWP2-OCT4-positive feedback loop might be used in the diagnosis and prognosis, as well as in the development of novel therapeutics for esophageal cancer. Show less

Anaphylaxis is a rapid and severe reaction to a trigger that is characterized by skin, mucosal, and cardiorespiratory changes. A minority of patients exhibit a biphasic anaphylactic reaction (BAR). Tirzepatide is a dual incretin receptor analog approved for the treatment of type 2 diabetes mellitus (T2DM). Allergic reactions to tirzepatide were reported during clinical trials, but none were severe enough to be characterized as an anaphylactic reaction. We describe a case of a BAR to tirzepatide. Show less

The development of single-molecule co-agonists for the glucagon-like peptide-1 (GLP-1) receptor (GLP-1R) and glucose-dependent insulinotropic polypeptide (GIP) receptor (GIPR) is considered a breakthrough in the treatment of obesity and type 2 diabetes. But although GIPR-GLP-1R co-agonism decreases body weight with superior efficacy relative to GLP-1R agonism alone in preclinical Show less

The melanocortin 4 receptor (MC4R) is a G protein-coupled transporter that mediates the regulation of thyroid hormones and leptin on energy balance and food intake. However, the mechanisms of transcriptional regulation of Mc4r by thyroid hormone and leptin in fish have been rarely reported. The messenger RNA expression of Mc4r gene was significantly higher in brain than those in other tissues of mandarin fish. We analyzed the structure and function of a 2029 bp sequence of Mc4r promoter. Meanwhile, overexpression of NKX2.1 and incubation with leptin significantly increased Mc4r promoter activity, but triiodothyronine showed the opposite effect. In addition, mutations in the NKX2.1 binding site abolished not only the activation of Mc4r promoter activity by leptin but also the inhibitory effect of thyroid hormones on Mc4r promoter activity. In summary, these results suggested that thyroid hormones and leptin might regulate the transcriptional expression of Mc4r through NKX2.1. Show less

The meat of Tibetan sheep has a unique flavor, delicious taste, and superior nutritional value. However, the change of grass will lead to a change in meat quality. This study aimed to explore the potential regulatory mechanisms of microbial metabolites with respect to meat quality traits of Tibetan sheep under nutrient stress in the cold season. We determined and analyzed the longissimus dorsi quality, fatty acid composition, expression of genes, and rumen microbial metabolites of Tibetan sheep in cold and warm seasons. The shear force was decreased (P < .05), the meat color a*24 h value was increased (P < .05), and the contents of crude fat (EE) and protein (CP) were decreased in the cold season. Polyunsaturated fatty acids (PUFAs)-linoleic acid and docosahexaenoic acid increased significantly in the cold season (P < .05). The expressions of meat quality genes MC4R, CAPN1, H-FABP, and LPL were significantly higher in the warm season (P < .05), and the CAST gene was significantly expressed in the cold season (P < .01). The different microbial metabolites of Tibetan sheep in the cold and warm seasons were mainly involved in amino acid metabolism, lipid metabolism, and digestive system pathway, and there was some correlation between microbiota and meat quality traits. There are similarities between microbial metabolites enriched in the lipid metabolism pathway and muscle metabolites. Under nutritional stress in the cold season, the muscle tenderness of Tibetan sheep was improved, and the fat deposition capacity was weakened, but the levels of beneficial fatty acids were higher than those in the warm season, which was more conducive to healthy eating. Show less

Proopiomelanocortin (POMC) is a hormone precursor, and has been reported to participate in domestication. However, its effects on feeding habit domestication in fish are poorly understood. Mandarin fish (Siniperca chuatsi) feeds solely on live prey fish since first-feeding. In the present study, the high expression of pomc in mandarin fish, both the pomc siRNA and MC4R inhibitor treatments increased the success rate of domestication from live prey fish to dead prey fish and food intake of dead prey fish, suggesting the role of pomc on the special feeding habit of live prey fish in mandarin fish. In addition, one c-fos binding site was identified in the region that from -1053 bp to -931 bp upstream of the transcription start site of pomc, and this region exhibited positive promoter activity. The mandarin fish brain cells treated with c-fos siRNA displayed suppressed pomc mRNA expression, indicating that c-fos positively regulated pomc expression. Furthermore, the mRNA expression of c-fos was higher in the mandarin fish which were more difficult to domesticate. The results of ChIP assay and inhibitor treatment confirmed that the activation of c-fos gene by histone H3K4me3 was catalyzed by Setd1b in mandarin fish. Three open peaks were found at the upstream regulatory region of setd1b by ATAC-seq, and the mRNA expression of setd1b was higher in the mandarin fish which were more difficult to domesticate. These results indicated that Setd1b could methylate histone H3K4 to activate the c-fos transcription, maintaining the high expression of pomc, which might contribute to the special feeding habit of mandarin fish. Show less

The hormone leptin is known to robustly suppress food intake by acting upon the leptin receptor (LepR) signaling system residing within the agouti-related protein (AgRP) neurons of the hypothalamus. However, clinical studies indicate that leptin is undesirable as a therapeutic regiment for obesity, which is at least partly attributed to the poorly understood complex secondary structure and key signaling mechanism of the leptin-responsive neural circuit. Here, we show that the LepR-expressing portal neurons send GABAergic projections to a cohort of α3-GABA Show less

In mammalian ovaries, the balance between dormancy and activation of primordial follicles determines the female fecundity and endocrine homeostasis. Recently, several functional molecules and pathways have been reported to be involved in the activation of primordial follicles. However, the homeostasis regulatory mechanisms of primordial follicle activation are still scant. Our previous study has proved that a relatively higher concentration of cyclic AMP (cAMP) is required for primordial follicle formation. Here, we identified that cAMP also plays a vital role in the balance between dormancy and activation of primordial follicles. Our results showed that the concentration of cAMP remained stable in neonatal mouse ovaries, which is due to ADCY3, the synthetase of cAMP, and PDE3A, the hydrolytic enzyme of cAMP, were synchronously increased during the activation of primordial follicles in mouse ovaries. Once the concentration of cAMP in neonatal ovaries was either elevated or reduced in vitro, the activation of primordial follicles was either accelerated or decelerated accordingly. In addition, a higher concentration of cAMP in the ovaries of puberty mice improved primordial follicle activation in vivo. Finally, cAMP promoted primordial follicle activation via canonical mTORC1-PI3K signaling cascades and PKA signaling. In conclusion, our findings reveal that the concentration of cAMP acts as a key regulator in balancing the dormancy and activation of primordial follicles in the mouse ovary. Show less

Although it has been established that cancer-associated fibroblasts (CAFs) facilitate tumor development, the relationship between CAFs and the prognosis of patients with lung adenocarcinoma (LUAD) has not been extensively explored. This study was formulated to investigate the prognostic value of CAF-related genes in LUAD. Differential analysis was carried out with TCGA-LUAD dataset as the training set. By overlapping differentially expressed genes (DEGs) with genes associated with CAF, CAF-related DEGs specific to LUAD were obtained. A prognostic risk model was constructed by Lasso and Cox regression analysis, and samples were grouped according to median risk score. The efficacy of the model was accessed through survival curve and receiver operating characteristic curve (ROC) analyses, with the validation set for verification. Risk score combined with clinical factors was utilized for Cox analysis to verify the independence of the model, and a nomogram was drawn. GSEA was performed on different risk groups. Immunologic infiltration and tumor mutational burden were assessed in different risk groups. Eleven feature genes including DLGAP5, KCNE2, UPK2, NPAS2, ARHGAP11A, ANGPTL4, ANLN, DKK1, SMUG1, C16orf74, and ACAD8 were identified, based on which a prognostic model was constructed. Risk score could predict the prognosis of LUAD patients and could be an independent prognostic factor for LUAD patients. GSEA outcomes displayed significant enrichment of genes in the high-risk group in the P53 SIGNALING PATHWAY. In comparison to the low-risk group, the high-risk group exhibited a decreased degree of immune infiltration and an elevated level of tumor mutational burden. An 11-gene model was constructed based on CAF-related genes to predict LUAD prognosis. This model represented an independent prognostic factor for LUAD. Show less

Angiopoietin-like 4 (ANGPTL4) belongs to the angiopoietin-like protein family and mediates the inhibition of lipoprotein lipase activity. Emerging evidence suggests that ANGPTL4 has pleiotropic functions with anti- and pro-inflammatory properties. A thorough search on PubMed related to ANGPTL4 and inflammation was performed. Genetic inactivation of ANGPTL4 can significantly reduce the risk of developing coronary artery disease and diabetes. However, antibodies against ANGPTL4 result in several undesirable effects in mice or monkeys, such as lymphadenopathy and ascites. Based on the research progress on ANGPTL4, we systematically discussed the dual role of ANGPTL4 in inflammation and inflammatory diseases (lung injury, pancreatitis, heart diseases, gastrointestinal diseases, skin diseases, metabolism, periodontitis, and osteolytic diseases). This may be attributed to several factors, including post-translational modification, cleavage and oligomerization, and subcellular localization. Understanding the potential underlying mechanisms of ANGPTL4 in inflammation in different tissues and diseases will aid in drug discovery and treatment development. Show less

Sodium-glucose co-transporter 2 (SGLT2) inhibitors reduced the risk of cardiovascular and renal outcomes in patients with type 2 diabetes (T2D), but the underlying mechanism has not been well elucidated. The circulating levels of proteins and metabolites reflect the overall state of the human body. This study aimed to evaluate the effect of dapagliflozin on the proteome and metabolome in patients with newly diagnosed T2D. A total of 57 newly diagnosed T2D patients were enrolled, and received 12 weeks of dapagliflozin treatment (10 mg/d, AstraZeneca). Serum proteome and metabolome were investigated at the baseline and after dapagliflozin treatment. Dapagliflozin significantly decreased HbA1c, BMI, and HOMA-IR in T2D patients (all p < 0.01). Multivariate models indicated clear separations of proteomics and metabolomics data between the baseline and after dapagliflozin treatment. A total of 38 differentially abundant proteins including 23 increased and 15 decreased proteins, and 35 differentially abundant metabolites including 17 increased and 18 decreased metabolites, were identified. In addition to influencing glucose metabolism (glycolysis/gluconeogenesis and pentose phosphate pathway), dapagliflozin significantly increased sex hormone-binding globulin, transferrin receptor protein 1, disintegrin, and metalloprotease-like decysin-1 and apolipoprotein A-IV levels, and decreased complement C3, fibronectin, afamin, attractin, xanthine, and uric acid levels. The circulating proteome and metabolome in newly diagnosed T2D patients were significantly changed after dapagliflozin treatment. These changes in proteins and metabolites might be associated with the beneficial effect of dapagliflozin on cardiovascular and renal outcomes. Show less

Determining a non-invasive, serum-based diagnostic panel for early diagnosis of AD will play a significant role in the prevention and treatment of the disease. We performed standardized clinical assessments and neuroimaging measurements in 45 patients with AD and an equal number of sex - and age-matched controls. 48 target peptides of 14 identified target proteins were quantitatively analyzed by PRM. 8 protein markers were screened, including SAA4, PPBP, PF4, APOA4, F10, CPB2, C1S and IGHM. An diagnosis panel including 8 proteins and demographic characteristics markers respectively was found to be the robust with a AUC of 92.3%. Our study developed a new panel including protein and demographic characteristics that could be used to distinguish AD from control candidates. Show less

Mulberry (Morus alba L.) leaf, as a medicinal and food homologous traditional Chinese medicine, has a clear therapeutic effect on type 2 diabetes mellitus (T2DM), yet its underlying mechanisms have not been totally clarified. The study aimed to explore the mechanism of mulberry leaf in the treatment of T2DM through tandem mass tag (TMT)-based quantitative proteomics analysis of skeletal muscle. The anti-diabetic activity of mulberry leaf extract (MLE) was evaluated by using streptozotocin-induced diabetic rats at a dose of 4.0 g crude drug /kg p.o. daily for 8 weeks. Fasting blood glucose, body weight, food and water intake were monitored at specific intervals, and oral glucose tolerance test and insulin tolerance test were conducted at the 7th and 8th week respectively. At the end of the experiment, levels of glycated hemoglobin A1c, insulin, free fat acid, leptin, adiponectin, total cholesterol, triglyceride, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol were assessed and the pathological changes of rat skeletal muscle were observed by HE staining. TMT-based quantitative proteomic analysis of skeletal muscle and bioinformatics analysis were performed and differentially expressed proteins (DEPs) were validated by western blot. The interactions between the components of MLE and DEPs were further assessed using molecular docking. After 8 weeks of MLE intervention, the clinical indications of T2DM such as body weight, food and water intake of rats were improved to a certain extent, while insulin sensitivity was increased and glycemic control was improved. Serum lipid profiles were significantly reduced, and the skeletal muscle fiber gap and atrophy were alleviated. Proteomic analysis of skeletal muscle showed that MLE treatment reversed 19 DEPs in T2DM rats, regulated cholesterol metabolism, fat digestion and absorption, vitamin digestion and absorption and ferroptosis signaling pathways. Key differential proteins Apolipoprotein A-1 (ApoA1) and ApoA4 were successfully validated by western blot and exhibited strong binding activity to the MLE's ingredients. This study first provided skeletal muscle proteomic changes in T2DM rats before and after MLE treatment, which may help us understand the molecular mechanisms, and provide a foundation for developing potential therapeutic targets of anti-T2DM of MLE. Show less

Systemic lupus erythematosus (SLE) is an autoimmune disease affecting thousands of people. There are still no effective biomarkers for SLE diagnosis and disease activity assessment. We performed proteomics and metabolomics analyses of serum from 121 SLE patients and 106 healthy individuals, and identified 90 proteins and 76 metabolites significantly changed. Several apolipoproteins and the metabolite arachidonic acid were significantly associated with disease activity. Apolipoprotein A-IV (APOA4), LysoPC(16:0), punicic acid and stearidonic acid were correlated with renal function. Random forest model using the significantly changed molecules identified 3 proteins including ATRN, THBS1 and SERPINC1, and 5 metabolites including cholesterol, palmitoleoylethanolamide, octadecanamide, palmitamide and linoleoylethanolamide, as potential biomarkers for SLE diagnosis. Those biomarkers were further validated in an independent cohort with high accuracy (AUC = 0.862 and 0.898 for protein and metabolite biomarkers respectively). This unbiased screening has led to the discovery of novel molecules for SLE disease activity assessment and SLE classification. Show less

Vascular dementia (VD), associated with cerebrovascular injury, is characterized by severe cognitive impairment. Jianpi Tianjing Decoction (JTD) has been widely used to treat VD. However, its molecular targets and mechanisms of action in this treatment remain unclear. This study integrated network pharmacology and proteomics to identify targets and mechanisms of JTD in the treatment of VD and to provide new insights and goals for clinical treatments. Systematic network pharmacology was used to identify active chemical compositions, potential targets, and mechanisms of JTD in VD treatment. Then, a mouse model of VD was induced via transient bilateral common carotid artery occlusion to verify the identified targets and mechanisms of JTD against VD using 4D label-free quantitative proteomics. By screening active chemical compositions and potential targets in relevant databases, 187 active chemical compositions and 416 disease-related compound targets were identified. JTD may suppress VD development via multiple components, targets, and pathways. It may thus serve as a complementary treatment option for patients with VD. Show less

Myocardial infarction (MI) is a major cause of death and disability worldwide, but current treatments are limited by their invasiveness, side effects, and lack of efficacy. Novel drug targets for MI prevention are urgently needed. In this study, we used Mendelian randomization to identify potential therapeutic targets for MI using plasma protein quantitative trait loci as exposure variables and MI as the outcome variable. We further validated our findings using reverse causation analysis, Bayesian co-localization analysis, and external datasets. We also constructed a protein-protein interaction network to explore the relationships between the identified proteins and known MI targets. Our analysis revealed 2 proteins, LPA and APOA5, as potential drug targets for MI, with causal effects on MI risk confirmed by multiple lines of evidence. LPA and APOA5 are involved in lipid metabolism and interact with target proteins of current MI medications. We also found 4 other proteins, IL1RN, FN1, NT5C, and SEMA3C, that may have potential as drug targets but require further confirmation. Our study demonstrates the utility of Mendelian randomization and protein quantitative trait loci in discovering novel drug targets for complex diseases such as MI. It provides insights into the underlying mechanisms of MI pathology and treatment. Show less

Currently, the prevalence of allergic rhinitis (AR) remains high and there is a great need to develop better and safer ways to alleviate AR symptoms. The Adults aged from 18 to 60 years old and previously suffered from AR were recruited and received GUANKE probiotics treatment for 4 weeks. The questionnaires of Total nasal symptom scores (TNSS), total non-nasal symptom score (TNNSS), and rhinitis control assessment test (RCAT) were used to assess the effectiveness before and after treatment. The serum allergen-specific IgE and cytokines were also determined at baseline and after 4 weeks of probiotics administration. The results showed that TNSS and TNNSS were significantly reduced and the RCAT score was significantly increased compared to baseline. The sub-symptom score of rhinorrhea, itching, sneezing, and tearing in each questionnaire also showed significant changes, and the serum IgE level was markedly decreased. We further measured inflammatory-related proteins in serum and found that a total of 20 proteins (6 upregulated and 14 downregulated) were significantly changed compared to baseline, including IL-4, IL-7, IL-20, IL-33, CXCL1, CXCL5, CXCL6, CXCL11, CCL4, CCL23, TGF-alpha, LAP-TGF-beta-1, MMP-1, MMP-10, AXIN1, NT-3, OSM, SCF, CD6, and NRTN. Enrichment analysis showed that these significantly altered proteins were mainly enriched in cytokine and chemokine-related signaling pathways. Taken together, this study demonstrated the Show less

FAT4 (FAT Atypical Cadherin 4) is a member of the cadherin-associated protein family, which has been shown to function as a tumor suppressor by inhibiting proliferation and metastasis. The Wnt/β-catenin pathway activation is highly associated with PD-L1-associated tumor immune escape. Here, we report the mechanism by which FAT4 overexpression regulates anti-tumor immunity in cervical cancer by inhibiting PD-L1 N-glycosylation and cell membrane localization in a β-catenin-dependent manner. FAT4 expression was first detected in cervical cancer tissues and cell lines. Cell proliferation, clone formation, and immunofluorescence were used to determine the tumor suppressive impact of FAT4 overexpression in vitro, and the findings were confirmed in immunodeficient and immunocomplete mice xenografts. Through functional and mechanistic experiments in vivo and in vitro, we investigated how FAT4 overexpression affects the antitumor immunity via the β-catenin/STT3/PD-L1 axis. FAT4 is downregulated in cervical cancer tissues and cell lines. We determined that FAT4 binds to β-catenin and antagonizes its nuclear localization, promotes phosphorylation and degradation of β-catenin by the degradation complexes (AXIN1, APC, GSK3β, CK1). FAT4 overexpression decreases programmed death-ligand 1 (PD-L1) mRNA expression at the transcriptional level, and causes aberrant glycosylation of PD-L1 via STT3A at the post-translational modifications (PTMs) level, leading to its endoplasmic reticulum (ER) accumulation and polyubiquitination-dependent degradation. We found that FAT4 overexpression promotes aberrant PD-L1 glycosylation and degradation in a β-catenin-dependent manner, thereby increasing cytotoxic T lymphocyte (CTL) activity in immunoreactive mouse models. These findings address the basis of Wnt/β-catenin pathway activation in cervical cancer and provide combination immunotherapy options for targeting the FAT4/β-catenin/STT3/PD-L1 axis. Schematic cartoons showing the antitumor immunity mechanism of FAT4. (left) when Wnts bind to their receptors, which are made up of Frizzled proteins and LRP5/6, the cytoplasmic protein DVL is activated, inducing the aggregation of degradation complexes (AXIN, GSK3β, CK1, APC) to the receptor. Subsequently, stable β-catenin translocates into the nucleus and binds to TCF/LEF and TCF7L2 transcription factors, leading to target genes transcription. The catalytically active subunit of oligosaccharyltransferase, STT3A, enhances PD-L1 glycosylation, and N-glycosylated PD-L1 translocates to the cell membrane via the ER-to-Golgi pathway, resulting in immune evasion. (Right) FAT4 exerts antitumor immunity mainly through following mechanisms: (i) FAT4 binds to β-catenin and antagonizes its nuclear localization, promotes phosphorylation and degradation of β-catenin by the degradation complexes (AXIN1, APC, GSK3β, CK1); (ii) FAT4 inhibits PD-L1 and STT3A transcription in a β-catenin-dependent manner and induces aberrant PD-L1 glycosylation and ubiquitination-dependent degradation; (iii) Promotes activation of cytotoxic T lymphocytes (CTL) and infiltration into the tumor microenvironment. Show less

Wnt/β-catenin signaling is a conserved pathway crucially governing development, homeostasis, and oncogenesis. Discoveries of its regulators hold great values in both basic and translational research. Through screening, we identified a deubiquitinase, USP10, as a critical modulator of β-catenin. Mechanistically, USP10 binds to key scaffold Axin1 via conserved motifs and stabilizes Axin1 through K48-linked deubiquitination. Surprisingly, USP10 physically tethers Axin1 and β-catenin and promotes the phase separation for β-catenin suppression regardless of the enzymatic activity. Function-wise, USP10 enzymatic activity preferably regulates embryonic development and both the enzymatic activity and physical function jointly control intestinal homeostasis by antagonizing β-catenin. In colorectal cancer, USP10 substantially represses cancer growth mainly through physical promotion of phase separation and correlates with Wnt/β-catenin magnitude clinically. Collectively, we discovered USP10 functioning in multiple biological processes against β-catenin and unearthed the enzyme-dependent and -independent "dual-regulating" mechanism. These two functions of USP10 work in parallel and are context dependent. Show less

PARPs, which are members of the poly(ADP-ribose) polymerase superfamily, promote tumorigenesis and tumour-associated inflammation and are thus therapeutic targets for several cancers. The aim of the present study is to investigate the mechanistic insight into the roles PARPs for inflammation. Primary murine macrophages were cultured in the presence or absence of the PARP5 inhibitor NVP-TNKS656 to examine the role of PARP5 for cytokine production. In contrast to the roles of other PARPs for induction of inflammation, we found in the present study that pharmacologic inhibition of PARP5 induces production of inflammatory cytokines in primary murine macrophages. We found that treatment with the PARP5 inhibitor NVP-TNKS656 in macrophages enhanced steady-state and LPS-mediated cytokine production through degradation of IκBα and subsequent nuclear translocation of NF-κB. We also found that pharmacologic inhibition of PARP5 stabilises the adaptor protein 3BP2, a substrate of PARP5, and that accelerated cytokine production induced by PARP5 inhibition was rescued in 3BP2-deleted macrophages. Additionally, we found that LPS increases the expression of 3BP2 and AXIN1, a negative regulator of β-catenin, through suppression of PARP5 transcripts in macrophages, leading to further activation of cytokine production and inhibition of β-catenin-mediated cell proliferation, respectively. Lastly, we found that PARP5 inhibition in macrophages promotes osteoclastogenesis through stabilisation of 3BP2 and AXIN1, leading to activation of SRC and suppression of β-catenin, respectively. Our results show that pharmacologic inhibition of PARP5 against cancers unexpectedly induces adverse autoinflammatory side effects through activation of innate immunity, unlike inhibition of other PARPs. Show less

Recent studies have demonstrated the association of APP and Aβ with cancer, suggesting that BACE1 may play an important role in carcinogenesis. In the present study, we assessed BACE1's usefulness as a therapeutic target in prostate cancer (PCa). BACE1 expression was observed in human PCa tissue samples, patient-derived xenografts (PDX), human PCa xenograft tissue in nude mice, and transgenic adenocarcinoma of the mouse prostate (TRAMP) tissues by immunohistochemistry (IHC) analysis. Additionally, the downstream product of BACE1 activity, i.e., Aβ1-42 expression, was also observed in these PCa tissues by IHC as well as by PET imaging in TRAMP mice. Furthermore, BACE1 gene expression and activity was confirmed in several established PCa cell lines (LNCaP, C4-2B-enzalutamide sensitive [S], C4-2B-enzalutamide resistant [R], 22Rv1-S, 22Rv1-R, PC3, DU145, and TRAMP-C1) by real-time PCR and fluorometric assay, respectively. Treatment with a pharmacological inhibitor of BACE1 (MK-8931) strongly reduced the proliferation of PCa cells in in vitro and in vivo models, analyzed by multiple assays (MTT, clonogenic, and trypan blue exclusion assays and IHC). Cell cycle analyses revealed an increase in the sub-G1 population and a significant modulation in other cell cycle stages (G1/S/G2/M) following MK-8931 treatment. Most importantly, in vivo administration of MK-8931 intraperitoneal (30 mg/kg) strongly inhibited TRAMP-C1 allograft growth in immunocompetent C57BL/6 mice (approximately 81% decrease, Show less

Hematoma-induced neuroinflammation is the cause of poor prognosis in intracerebral hemorrhage (ICH); therefore, promoting blood clearance and blocking overactivated inflammation are rational approaches for ICH treatment. β-site amyloid precursor protein (APP) lyase-1 (BACE1) is a key molecule regulating the microglial phenotype transition in neurodegenerative diseases. Therefore, the aim of this study was to investigate the role of BACE1 in microglial phagocytosis and inflammatory features in ICH. Here, we demonstrated the unique advantages of targeting BACE1 in microglia using an autologous blood model and primary microglia hemoglobin stimulation. When BACE1 was inhibited early in ICH, fewer residual hematomas remained, consistent with an increase in genetic features that favor phagocytosis and anti-inflammation. In addition, inhibition of BACE1 enhanced the secretion of anti-inflammatory cytokines and substantially reduced the expression of proinflammatory genes, which was regulated by signal transduction and phosphorylation of activator of transcription 3 (STAT3). Further pharmacological inhibition of STAT3 phosphorylation effectively blocked the proinflammatory and weak phagocytic phenotype of microglia due to BACE1 induction. In summary, BACE1 is the critical molecule regulating the inflammatory and phagocytic phenotypes of microglia after ICH, and targeted inhibition of the BACE1/STAT3 pathway is an important strategy for the future treatment of ICH-induced neurological injury. Show less