👤 Zhewei Kang

Axin1 is a key regulator of canonical Wnt signaling pathway. Roles of Axin1 in skeletal development and in disease occurrence have not been fully defined. Here, we report that Axin1 is essential for lower limb development. Specific deletion of Show less

The amplitude of Wnt/β-catenin signaling is precisely controlled by the assembly of the cell surface-localized Wnt receptor signalosome and the cytosolic β-catenin destruction complex. How these two distinct complexes are coordinately controlled remains largely unknown. Here, we demonstrated that the signalosome scaffold protein Dishevelled 2 (Dvl2) undergoes liquid-liquid phase separation (LLPS). Dvl2 LLPS is mediated by an intrinsically disordered region and facilitated by components of the signalosome, such as the receptor Fzd5. Assembly of the signalosome is initiated by rapid recruitment of Dvl2 to the membrane, followed by slow and dynamic recruitment of Axin1. Axin LLPS mediates assembly of the β-catenin destruction complex, and Dvl2 attenuates LLPS of Axin. Compared with the destruction complex, Axin partitions into the signalosome at a lower concentration and exhibits a higher mobility. Together, our results revealed that Dvl2 LLPS is crucial for controlling the assembly of the Wnt receptor signalosome and disruption of the phase-separated β-catenin destruction complex. Show less

Methamphetamine (Meth), a central nervous system (CNS) stimulant with strong neurotoxicity, causes progressive cognitive impairment with characterized neurodegenerative changes. However, the mechanism underlying Meth-induced pathological changes remains poorly understood. In the current study, Meth elicited a striking accumulation of the pathological proteins hyperphosphorylated tau (p-tau) and amyloid beta (A Show less

The chromobox family, a critical component of epigenetic regulators, participates in the tumorigenesis and progression of many malignancies. However, the roles of the CBX family members (CBXs) in glioblastoma (GBM) remain unclear. The mRNA expression of CBXs was analyzed in tissues and cell lines by Oncomine and Cancer Cell Line Encyclopedia (CCLE). The differential expression of CBXs at the mRNA level was explored in The Cancer Genome Atlas (TCGA) and Chinese Glioma Genome Atlas (CGGA) databases with the "beeswarm" R package. The protein expression of CBXs in GBM was further examined on Human Protein Atlas (HPA). The correlations between CBXs and IDH mutation and between CBXs and GBM subtypes were investigated in the TCGA portal and CGGA database with the "survminer" R package. The alteration of CBXs and their prognostic value were further determined CBXs presented significantly differential expressions in pan-cancers. CBX2/3/5/8 were upregulated, whereas CBX6/7 were downregulated at mRNA level in GBM of TCGA and CGGA databases. Similarly, high expression of CBX2/3/5 and low expression of CBX6/8 were further confirmed at the protein level in the HPA. CBX2/6/7 were positively correlated with IDH mutation and CBX1/2/4/5/8 were closely related to GBM subtypes. CBX7 and CBX8 presented the independent prognostic factors for GBM patient survival. GO and KEGG analyses indicated that CBXs were closely related to the histone H3-K36, PcG protein complex, ATPase, and Wnt pathway. The overexpression of CBX7 and underexpression of CBX8 significantly inhibited the proliferation and invasion of glioma cells Our results suggested that CBX7 and CBX8 served as independent prognostic indicators that promoted the proliferation and invasion of glioma cells, providing a promising strategy for diagnosing and treating GBM. Show less

Cutaneous squamous cell carcinoma (cSCC) is the second most common skin cancer, and photodynamic therapy (PDT) is a promising modality against cSCC. This study investigated the impact of PDT on the MAPK pathway and cell cycle alternation of cSCC as well as the related molecular mechanisms. Expressing mRNA profile data sets GSE98767, GSE45216, and GSE84758 were acquired from the GEO database. The functions of differently expressed genes (DEGs) were enriched by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. Least absolute shrinkage and selection operator (Lasso) analysis were used to establish a diagnosis model based on GSE98767. A correlation analysis and a protein-protein interaction (PPI) network were used to evaluate the relationship between cSCC-PDT-related genes and the MAPK pathway. Single-sample gene set enrichment analysis (ssGSEA) was performed on GSE98767 to estimate MAPK activation and cell cycle activity. Finally, the effect of MAPK activation on the cell cycle was explored Four cSCC-PDT-related genes, DUSP6, EFNB2, DNAJB1, and CCNL1, were identified as diagnostic markers of cSCC, which were upregulated in cSCC or LC50 PDT-protocol treatment and negatively correlated with the MAPK promoter. Despite having a smaller MAPK activation score, cSCC showed higher cell cycle activity. The PDT treatment suppressed the G1 to G2/M phase in JNK overexpressed A431 cells. CCNL1, DNAJB1, DUSP6, and EFNB2 were identified as potential PDT target genes in cSCC treatment, whose potential therapeutic mechanism was inhibiting the MAPK pathway and inducing cell cycle alternation. Show less

Postmenopausal osteoporosis (PMOP) is known as one of the prevalent diseases among middle-aged and elderly women. This paper revolves around the alteration of miR-211-5p in PMOP patients and its function in osteogenic differentiation. Quantitative real-time polymerase chain reaction (qRT-PCR) was implemented to check the miR-211-5p level in the plasma of PMOP patients. Knockdown and overexpression experiments were done to verify the influence of miR-211-5p on human-derived mesenchymal stem cell (hMSC) osteogenic differentiation and osteogenesis. The alkaline phosphatase (ALP) assay kit was taken to test ALP activity. Alizarin red staining monitored osteogenic differentiation, while oil red O staining examined adipogenesis. Western blot confirmed the profiles of osteoclastogenesis-concerned factors (TRAP, NFAT2, c-FOS, Runx2, OCN, CTSK), dual specific phosphatase 6 (DUSP6), ERK, SMAD, and β-catenin. Dual-luciferase reporter and RNA immunoprecipitation assays were implemented to identify the association between miR-211-5p and DUSP6. Our data displayed that miR-211-5p was down-regulated in the PMOP patients' plasma (in contrast with the healthy controls), and it was positively correlated with Vit-D and BMD levels. miR-211-5p overexpression vigorously facilitated hMSC osteogenic differentiation, while miR-211-5p inhibition contributed to the opposite situation. miR-211-5p initiated the ERK/SMAD/β-catenin pathway and repressed DUSP6's expression. Overexpression of DUSP6 counteracted the miR-211-5p-mediated function to a great extent and inactivated ERK/SMAD/β-catenin, whereas enhancing ERK phosphorylation weakened the DUSP6 overexpression-induced function. Consequently, this research unveiled that miR-211-5p promotes osteogenic differentiation by interfering with the DUSP6-mediated ERK/SMAD/β-catenin pathway. Show less

Temporomandibular joint disorder is defined by pain and/or loss of function of the temporomandibular joint and its associated muscles and structures. Treatments include noninvasive pharmacologic therapies, minimally invasive muscular and articular injections, and surgery. Conservative therapies include nonsteroidal anti-inflammatory drugs, muscle relaxants, benzodiazepines, antidepressants, and anticonvulsants. Minimally invasive injections include botulinum toxin, corticosteroids, platelet-rich plasma, hyaluronic acid, and prolotherapy with hypertonic glucose. With many pharmacologic treatment options and modalities available to the oral and maxillofacial surgeon, mild to moderate temporomandibular joint disorder can be managed safely and effectively to improve symptoms of pain and function of the temporomandibular joint. Show less

Interleukin-27 is constitutively secreted by microglia in the retina or brain, and upregulation of IL-27 during neuroinflammation suppresses encephalomyelitis and autoimmune uveitis. However, while IL-35 is structurally and functionally similar to IL-27, the intrinsic roles of IL-35 in CNS tissues are unknown. Thus, we generated IL-35/YFP-knock-in reporter mice (p35-KI) and demonstrated that photoreceptor neurons constitutively secrete IL-35, which might protect the retina from persistent low-grade inflammation that can impair photoreceptor functions. Furthermore, the p35-KI mouse, which is hemizygous at the Show less

Cytokines are important immunotherapeutics with approved drugs for the treatment of human cancers. However, systemic administration of cytokines often fails to achieve adequate concentrations to immune cells in tumors due to dose-limiting toxicity. Thus, developing localized therapy that directly delivers immune-stimulatory cytokines to tumors may improve the therapeutic efficacy. In this study, we generated novel lipid nanoparticles (LNPs) encapsulated with mRNAs encoding cytokines including IL-12, IL-27 and GM-CSF, and tested their anti-tumor activity. We first synthesized ionizable lipid materials containing di-amino groups with various head groups (DALs). The novel DAL4-LNP effectively delivered different mRNAs in vitro to tumor cells and in vivo to tumors. Intratumoral injection of DAL4-LNP loaded with IL-12 mRNA was most potent in inhibiting B16F10 melanoma tumor growth compared to IL-27 or GM-CSF mRNAs in monotherapy. Furthermore, intratumoral injection of dual DAL4-LNP-IL-12 mRNA and IL-27 mRNA showed a synergistic effect in suppressing tumor growth without causing systematic toxicity. Most importantly, intratumoral delivery of IL-12 and IL-27 mRNAs induced robust infiltration of immune effector cells, including IFN-γ and TNF-α producing NK and CD8 Show less

Investigation of associated risk factors of valproic acid (VPA)-induced tremor helped in increasing tolerance and optimizing treatment scheme individually. To determine the risk factors of VPA-induced tremor, with particular attention on identifying tremor-susceptible gene mutations. Epileptic patients taking VPA were divided into a tremor and a non-tremor groups. A mutation of rs9652490 in the leucine-rich repeat and immunoglobulin domain-containing Nogo-receptor-interacting protein 1 (LINGO-1) gene was determined by Sanger sequencing. Cerebellar atrophy was assessed, and various cerebellar dimensions were measured on magnetic resonance imaging (MRI) scans. One hundred and eighty-one of 200 subjects were included. Multivariate regression analysis indicated several VPA-induced tremor-related factors: females (OR = 2.718, p = 0.014), family history of tremor (OR = 7.595, p = 0.003), treatment duration (> 24 months; OR = 3.294, p = 0.002), and daily dosage (> 1,000 mg/d; OR = 19.801, p = 0.008) of VPA. Chi-square tests revealed that treatment with VPA magnesium-ER (p = 0.030) and carbamazepine combination (p = 0.040) reduced the incidence of tremor. One hundred and seventy-six gene sequencing and 86 MRI results excluded any significant difference between the two groups in the mutation of rs9652490 within LINGO-1, the ratio of cerebellar atrophy or the cerebellar-dimension values (p > 0.05). However, mutation of rs9652490 within LINGO-1 was correlated with increased cerebellar atrophy (p = 0.001), reduced cerebellar hemisphere thickness (p = 0.025), and right cerebellar hemisphere longitudinal diameter (p = 0.047). Our cohort indicated risk (female, positive family history of tremor, daily dosage > 1000 mg and treatment duration > 24 months of VPA) and protective factors (VPA magnesium-ER and combination with CBZ) of VPA-induced tremor. Mutation of rs9652490 within LINGO-1 correlated with cerebellar atrophy, neither was correlated with VPA-induced tremor. Show less

Characterizing the tumor microenvironment (TME) and immune landscape of cancer has been a promising step towards discovering new therapeutic biomarkers and guiding precision medicine; however, its application in mucoepidermoid carcinoma (MEC) has been sparse. Here, we conducted a comprehensive study to understand the properties of the TME and immune profiles of MEC. 20 patients with MEC were collected from Yonsei Head and Neck Cancer Centre, Yonsei University, South Korea. Total RNA sequencing was conducted to determine gene expression profiles. Bioinformatic and immunoinformatic analyses were applied to characterize the TME and identify immunophenotypic subgroups, and to investigate the molecular features that explain the distinct phenotypes. The MEC samples were subdivided into two groups, immune hot and immune cold, based on the heterogenous immune cell-infiltration and activation level. The immune-hot subgroup exhibited a higher level of immune activity, including T cell infiltration, cytolytic score, IFN-γ, antigen-presenting machinery, and immune modulator genes. Further characterizing molecular features of two subgroups, downregulation of lipid metabolic regulators, including MLXIPL and FASN, and the migration of chemokines and leukocytes were observed, respectively. And, Group-specific expression of immune checkpoint molecules, such as TIGIT, PD-L2, and CTLA-4, was observed in the immune-hot group, which can be exploited as a potential immunotherapeutic biomarker. Immunophenotypically heterogeneous MEC subgroups analysis has shown distinctive molecular characteristics and provided potential treatment options. These findings yield new insights into TME of MEC and may help next step to study this uncharted cancer. Show less

The serum uric acid (SUA) level is an important determinant of gout, hypertension, metabolic syndrome, and cardiovascular disease. Although previous genome-wide studies have identified multiple genetic variants associated with SUA, most genetic analyses have focused on individuals with European ancestry; thus, understanding of the genetic architecture of SUA is currently limited for Asian populations. We conducted a genome-wide meta-analysis based on Korea Biobank data consistent with three cohorts; namely, the Korean Genome and Epidemiology Study (KoGES) Ansan and Ansung, KoGES Health Examinee, and KoGES Cardiovascular Disease Association studies. In total, 60,585 participants aged ≥40 years were included in the analysis of the three cohorts. We used logistic regression analyses to perform genome-wide association study (GWAS) adjustments for confounding variables. Subsequently, a meta-analysis was conducted by combining the analyses of the three GWASs. We identified 8,105 variants at 22 genetic loci with a P value < 5 × 10 Show less

In the clinical practice, the right ventricular (RV) manifestations have received less attention in hypertrophic cardiomyopathy (HCM). This paper aimed to evaluate the risk prediction value and genetic characteristics of RV involvement in HCM patients. A total of 893 patients with HCM were recruited. RV hypertrophy, RV obstruction, and RV late gadolinium enhancement were evaluated by echocardiography and/or cardiac magnetic resonance. Patients with any of the above structural abnormalities were identified as having RV involvement. All patients were followed with a median follow-up time of 3.0 years. The primary endpoint was cardiovascular death; the secondary endpoints were all-cause death and heart failure (HF)-related death. Survival analyses were conducted to evaluate the associations between RV involvement and the endpoints. Genetic testing was performed on 669 patients. RV involvement was recognized in 114 of 893 patients (12.8%). Survival analyses demonstrated that RV involvement was an independent risk factor for cardiovascular death (P = 0.002), all-cause death (P = 0.011), and HF-related death (P = 0.004). These outcome results were then confirmed by a sensitivity analysis. Genetic testing revealed a higher frequency of genotype-positive in patients with RV involvement (57.0% vs. 31.0%, P < 0.001), and the P/LP variants of MYBPC3 were more frequently identified in patients with RV involvement (30.4% vs. 12.0%, P < 0.001). Logistic analyses indicated the independent correlation between RV involvement and these genetic factors. RV involvement was an independent risk factor for cardiovascular death, all-cause death and HF-related death in HCM patients. Genetic factors might contribute to RV involvement in HCM. Show less

Background Myocardial replacement fibrosis is one of the major histologic features of hypertrophic cardiomyopathy (HCM), but its characteristics have not been well delineated. Purpose To clarify the characteristics of replacement fibrosis in HCM and to evaluate the prognostic value of the regional extent of fibrosis. Materials and Methods This prospective study evaluated participants with HCM who underwent contrast-enhanced cardiac MRI from March 2011 to April 2019. For each participant, global and 16-segment extent of late gadolinium enhancement (LGE) in the left ventricle (LV) at cardiac MRI was analyzed. The primary end point was all-cause death. Results Among the 798 study participants enrolled (median age, 49 years [interquartile range {IQR}: 38-59 years]; 508 men), 588 (74%) underwent whole-exome sequencing. Thirty-five participants (4%) experienced death from any cause during a median follow-up of 2.9 years (IQR: 1.5-4.7 years). Spearman analysis showed weak correlations between the extent of LGE and wall thickness (LGE of global LV and maximal LV wall thickness, Show less

The folded mitochondria inner membrane-cristae is the structural foundation for oxidative phosphorylation (OXPHOS) and energy production. By mechanically simulating mitochondria morphogenesis, we speculate that efficient sculpting of the cristae is organelle non-autonomous. It has long been inferred that folding requires buckling in living systems. However, the tethering force for cristae formation and regulation has not been identified. Combining electron tomography, proteomics strategies, super resolution live cell imaging and mathematical modeling, we reveal that the mitochondria localized actin motor-myosin 19 (Myo19) is critical for maintaining cristae structure, by associating with the SAM-MICOS super complex. We discover that depletion of Myo19 or disruption of its motor activity leads to altered mitochondria membrane potential and decreased OXPHOS. We propose that Myo19 may act as a mechanical tether for effective ridging of the mitochondria cristae, thus sustaining the energy homeostasis essential for various cellular functions. Show less

Hexokinase 2 (HK2), which catalyzes the first committed step in glucose metabolism, is induced in cancer cells. HK2's role in tumorigenesis has been attributed to its glucose kinase activity. Here, we describe a kinase independent HK2 activity, which contributes to metastasis. HK2 binds and sequesters glycogen synthase kinase 3 (GSK3) and acts as a scaffold forming a ternary complex with the regulatory subunit of protein kinase A (PRKAR1a) and GSK3β to facilitate GSK3β phosphorylation and inhibition by PKA. Thus, HK2 functions as an A-kinase anchoring protein (AKAP). Phosphorylation by GSK3β targets proteins for degradation. Consistently, HK2 increases the level and stability of GSK3 targets, MCL1, NRF2, and particularly SNAIL. In addition to GSK3 inhibition, HK2 kinase activity mediates SNAIL glycosylation, which prohibits its phosphorylation by GSK3. Finally, in mouse models of breast cancer metastasis, HK2 deficiency decreases SNAIL protein levels and inhibits SNAIL-mediated epithelial mesenchymal transition and metastasis. Show less

Salivary adenoid cystic carcinoma (SACC) is a malignant tumor, which is characterized by a higher incidence of distant metastasis. The aim of this study was to investigate the role and mechanism of protein kinase D1 (PKD1) in regulating the epithelial-mesenchymal transition (EMT) and promotes the metastasis in SACC. We analyzed the expression of PKD1 in 40 SACC patients and different metastatic potential cell lines. Then, we investigated whether the migration and growth of SACC were regulated by PKD1 using shRNA interference or inhibition of kinase active in vitro cell. Moreover, the mechanism by which PKD1 regulates the stability of Snail protein was determined. Finally, nude mice were used to testify the function of PKD1 via tail vein injection. PKD1 was correlated with metastasis and poor prognosis of SACC patients. PKD1 inhibition attenuated proliferation, migration, invasion, and EMT of SACC cells. Conversely, kinase active PKD1 could induce EMT and promoted cell migration in human HSG cell. Furthermore, downregulation of PKD1 regulated Snail via phosphorylation at Ser-11 on Snail protein and promotion of proteasome-mediated degradation, and reduced lung metastasis in vivo. Our results suggest that PKD1 induces the EMT and promotes the metastasis, which illustrate that PKD1 may be a potential prognostic biomarker and serve as a potential therapeutic target for SACC patients. Show less

NALCN channel mediates sodium leak currents and is important for maintaining proper resting membrane potential. NALCN and FAM155A form the core complex of the channel, the activity of which essentially depends on the presence of both UNC79 and UNC80, two auxiliary proteins. NALCN, FAM155A, UNC79, and UNC80 co-assemble into a large hetero-tetrameric channel complex. Genetic mutations of NALCN channel components lead to neurodevelopmental diseases. However, the structure and mechanism of the intact channel complex remain elusive. Here, we present the cryo-EM structure of the mammalian NALCN-FAM155A-UNC79-UNC80 quaternary complex. The structure shows that UNC79-UNC80 form a large piler-shaped heterodimer which was tethered to the intracellular side of the NALCN channel through tripartite interactions with the cytoplasmic loops of NALCN. Two interactions are essential for proper cell surface localization of NALCN. The other interaction relieves the self-inhibition of NALCN by pulling the auto-inhibitory CTD Interacting Helix (CIH) out of its binding site. Our work defines the structural mechanism of NALCN modulation by UNC79 and UNC80. Show less

Large-scale human exome sequencing can identify rare protein-coding variants with a large impact on complex traits such as body adiposity. We sequenced the exomes of 645,626 individuals from the United Kingdom, the United States, and Mexico and estimated associations of rare coding variants with body mass index (BMI). We identified 16 genes with an exome-wide significant association with BMI, including those encoding five brain-expressed G protein-coupled receptors ( Show less

Ovarian cancer (OV) is deemed the most lethal gynecological cancer in women. The aim of this study was to construct an effective gene prognostic model for predicting overall survival (OS) in patients with OV. The expression profiles of glycolysis-related genes (GRGs) and clinical data of patients with OV were extracted from The Cancer Genome Atlas (TCGA) database. Univariate, multivariate, and least absolute shrinkage and selection operator Cox regression analyses were conducted, and a prognostic signature based on GRGs was constructed. The predictive ability of the signature was analyzed using training and test sets. A gene risk signature based on nine GRGs (ISG20, CITED2, PYGB, IRS2, ANGPTL4, TGFBI, LHX9, PC, and DDIT4) was identified to predict the survival outcome of patients with OV. The signature showed a good prognostic ability for OV, particularly high-grade OV, in the TCGA dataset, with areas under the curve (AUC) of 0.709 and 0.762 for 3- and 5-year survival, respectively. Similar results were found in the test sets, and the AUCs of 3-, 5-year OS were 0.714 and 0.772 in the combined test set. And our signature was an independent prognostic factor. Moreover, a nomogram combining the prediction model and clinical factors was developed. Our study established a nine-GRG risk model and nomogram to better predict OS in patients with OV. The risk model represents a promising and independent prognostic predictor for patients with OV. Moreover, our study on GRGs could offer guidance for the elucidation of underlying mechanisms in future studies. Show less

Angiopoietin-like protein 4 (ANGPTL4) is a hypoxia-induced gene, and its high expression is associated with poor prognosis and promotion of tumour progression in several cancers. Some studies reported that ANGPTL4 is affected by epigenetic regulation. Our previous results demonstrated that ANGPTL4 is highly expressed in most lung cancer cell lines than in normal cell lines and is upregulated by HIF-1α accumulation under NiCl Show less

Farnesoid X receptor (FXR), a bile acid-activated nuclear receptor, is a potent regulator of glucose and lipid metabolism as well as of bile acid metabolism. Previous studies have demonstrated that FXR deficiency is associated with metabolic derangements, including atherosclerosis and nonalcoholic fatty liver disease (NAFLD), but its mechanism remains unclear. In this study, we investigated the role of FXR in atherosclerosis and NAFLD and the effect of peroxisome proliferator-activated receptor (PPAR) agonists in mouse models with FXR deficiency. En face lipid accumulation analysis, liver histology, serum levels of glucose and lipids, and mRNA expression of genes related to lipid metabolism were compared between apolipoprotein E (ApoE)-/- and ApoE-/-FXR-/- mice. The effects of PPARα and PPARγ agonists were also compared in both groups of mice. Compared with ApoE-/- mice, ApoE-/-FXR-/- mice showed more severe atherosclerosis, hepatic steatosis, and higher levels of serum cholesterol, low-density lipoprotein cholesterol, and triglycerides, accompanied by increased mRNA expression of FAS, ApoC2, TNFα, IL-6 (liver), ATGL, TGH, HSL, and MGL (adipocytes), and decreased mRNA expressions of CPT2 (liver) and Tfam (skeletal muscle). Treatment with a PPARα agonist, but not with a PPARγ agonist, partly reversed atherosclerosis and hepatic steatosis, and decreased plasma triglyceride levels in the ApoE-/-FXR-/- mice, in association with increased mRNA expression of CD36 and FATP and decreased expression of ApoC2 and ApoC3 (liver). Loss of FXR is associated with aggravation of atherosclerosis and hepatic steatosis in ApoE-deficient mice, which could be reversed by a PPARα agonist through induction of fatty acid uptake, β-oxidation, and triglyceride hydrolysis. Show less

Circular RNAs (circRNAs) can act as vital players in osteoarthritis (OA). However, the roles of circRNAs in OA remain obscure. Herein, we explored the roles of exosomal circRNA bromodomain and WD repeat domain containing 1(circ-BRWD1) in OA pathology. In vitro model of OA was constructed by treating CHON-001 cells with interleukin-1β (IL-1β). Quantitative real-time polymerase chain reaction (qRT-PCR) assay was used for circ-BRWD1, BRWD, miR-1277, and TNF receptor-associated factor 6 (TRAF6) levels. RNase R assay was conducted for the feature of circ-BRWD1. Transmission electron microscopy (TEM) was employed to analyze the morphology of exosomes. Western blot assay was performed for protein levels. Cell Counting Kit-8 (CCK-8) assay, flow cytometry analysis, and 5-Ethynyl-2'-deoxyuridine (EDU) assay were adopted for cell viability, apoptosis, and proliferation, respectively. Enzyme-linked immunosorbent assay (ELISA) was carried out for the concentrations of interleukin-6 (IL-6) and interleukin-8 (IL-8). Dual-luciferase reporter and RNA immunoprecipitation (RIP) assays were used to analyze the interaction between miR-1277 and circ-BRWD1 or TRAF6. Circ-BRWD1 was increased in OA cartilage tissues, IL-1β-treated CHON-001 cells, and the exosomes derived from IL-1β-treated CHON-001 cells. Exosome treatment elevated circ-BRWD1 level, while exosome blocker reduced circ-BRWD1 level in IL-1β-treated CHON-001 cells. Silencing of circ-BRWD1 promoted cell viability and proliferation and repressed apoptosis, inflammation, and extracellular matrix (ECM) degradation in IL-1β-stimulated CHON-001 cells. For mechanism analysis, circ-BRWD1 could serve as the sponge for miR-1277 to positively regulate TRAF6 expression. Moreover, miR-1277 inhibition ameliorated the effects of circ-BRWD1 knockdown on IL-1β-mediated CHON-001 cell damage. Additionally, miR-1277 overexpression relieved IL-1β-induced CHON-001 cell injury, while TRAF6 elevation restored the impact. Exosomal circ-BRWD1 promoted IL-1β-induced CHON-001 cell progression by regulating miR-1277/TRAF6 axis. Show less

Genetics-associated asthenoteratozoospermia is often seen in patients with multiple morphological abnormalities of the sperm flagella (MMAF). Although 24 causative genes have been identified, these explain only approximately half of patients with MMAF. Since sperm flagella and motile cilia (especially respiratory cilia) have similar axonemal structures, many patients with MMAF also exhibit respiratory symptoms, such as recurrent airway infection, chronic sinusitis, and bronchiectasis, which are frequently associated with primary ciliary dyskinesia (PCD), another recessive disorder. Here, exome sequencing was conducted to evaluate the genetic cause in 53 patients with MMAF and classic PCD/PCD-like symptoms. Two homozygous missense variants and a compound-heterozygous variant in the BRWD1 gene were identified in three unrelated individuals. BRWD1 staining was detected in the whole flagella and respiratory cilia of normal controls but was absent in BRWD1-mutated individuals. Transmission electron microscopy and immunostaining demonstrated that BRWD1 deficiency in human affected respiratory cilia and sperm flagella differently, as the absence of outer and inner dynein arms in sperm flagellum and respiratory cilia, while with a decreased number and outer doublet microtubule defects of respiratory cilia. To our knowledge, this is the first report of a BRWD1-variant-related disease in humans, manifesting as an autosomal recessive form of MMAF and PCD/PCD-like symptoms. Our data provide a basis for further exploring the molecular mechanism of BRWD1 gene during spermatogenesis and ciliogenesis. Show less

Alcohol-associated liver disease (ALD) is a major human health issue for which there are limited treatment options. Experimental evidence suggests that nutrition plays an important role in ALD pathogenesis, and specific dietary fatty acids, for example, n6 or n3-PUFAs, may exacerbate or attenuate ALD, respectively. The purpose of the current study was to determine whether the beneficial effects of n3-PUFA enrichment in ALD were mediated, in part, by improvement in Wnt signaling. Wild-type (WT) and fat-1 transgenic mice (that endogenously convert n6-PUFAs to n3) were fed ethanol (EtOH) for 6 weeks followed by a single LPS challenge. fat-1 mice had less severe liver damage than WT littermates as evidenced by reduced plasma alanine aminotransferase, hepatic steatosis, liver tissue neutrophil infiltration, and pro-inflammatory cytokine expression. WT mice had a greater downregulation of Axin2, a key gene in the Wnt pathway, than fat-1 mice in response to EtOH and LPS. Further, there were significant differences between WT and fat-1 EtOH+LPS-challenged mice in the expression of five additional genes linked to the Wnt signaling pathway, including Apc, Fosl1/Fra-1, Mapk8/Jnk-1, Porcn, and Nkd1. Compared to WT, primary hepatocytes isolated from fat-1 mice exhibited more effective Wnt signaling and were more resistant to EtOH-, palmitic acid-, or TNFα-induced cell death. Further, we demonstrated that the n3-PUFA-derived lipid mediators, resolvins D1 and E1, can regulate hepatocyte expression of several Wnt-related genes that were differentially expressed between WT and fat-1 mice. These data demonstrate a novel mechanism by which n3-PUFAs can ameliorate ALD. Show less

Regulatory B cells (Breg cells) that secrete IL-10 or IL-35 (i35-Breg) play key roles in regulating immunity in tumor microenvironment or during autoimmune and infectious diseases. Thus, loss of Breg function is implicated in development of autoimmune diseases while aberrant elevation of Breg prevents sterilizing immunity, exacerbates infectious diseases, and promotes cancer metastasis. Breg cells identified thus far are largely antigen-specific and derive mainly from B2-lymphocyte lineage. Here, we describe an innate-like IL-27-producing natural regulatory B-1a cell (i27-Breg) in peritoneal cavity and human umbilical cord blood. i27-Bregs accumulate in CNS and lymphoid tissues during neuroinflammation and confers protection against CNS autoimmune disease. i27-Breg immunotherapy ameliorated encephalomyelitis and uveitis through up-regulation of inhibitory receptors (Lag3, PD-1), suppression of Th17/Th1 responses, and propagating inhibitory signals that convert conventional B cells to regulatory lymphocytes that secrete IL-10 and/or IL-35 in eye, brain, or spinal cord. Furthermore, i27-Breg proliferates in vivo and sustains IL-27 secretion in CNS and lymphoid tissues, a therapeutic advantage over administering biologics (IL-10, IL-35) that are rapidly cleared in vivo. Mutant mice lacking irf4 in B cells exhibit exaggerated increase of i27-Bregs with few i35-Bregs, while mice with loss of irf8 in B cells have abundance of i35-Bregs but defective in generating i27-Bregs, identifying IRF8/BATF and IRF4/BATF axis in skewing B cell differentiation toward i27-Breg and i35-Breg developmental programs, respectively. Consistent with its developmental origin, disease suppression by innate i27-Bregs is neither antigen-specific nor disease-specific, suggesting that i27-Breg would be effective immunotherapy for a wide spectrum of autoimmune diseases. Show less

The interaction of the solo H3K79 methyltransferase DOT1-like (DOT1L) and its regulatory factor ALL1-fused gene from chromosome 10 protein (AF10) is crucial for the transcription of developmental genes such as HOXA in acute leukemia. The octapeptide motif and leucine zipper region of AF10 is responsible for binding DOT1L and catalyzing H3K79 monomethylation to demethylation. However, the characteristics of the mechanism between DOT1L and AF10 are not clear. Here, we present the crystal structures of coiled-coil regions of DOT1L-AF10 and AF10-inhibitory peptide, demonstrating the inhibitory peptide could form a compact complex with AF10 via a different recognition pattern. Furthermore, an inhibitory peptide with structure-based optimization is identified and decreases the HOXA gene expression in a human cell line. Our studies provide an innovative pharmacologic basis for therapeutic intervention in leukemia. Show less

Macroautophagy/autophagy is a membrane-mediated intracellular degradation pathway, through which bulky cytoplasmic content is digested in lysosomes. How the autophagy initiation and maturation steps are regulated is not clear. In this study, we found an E3 ubiquitin ligase complex, linear ubiquitin chain assembly complex (LUBAC) and a deubiquitinating enzyme (DUB) OTULIN localize to the phagophore area to control autophagy initiation and maturation. LUBAC key component RNF31/HOIP translocates to the LC3 puncta area when autophagy is induced. Show less