Human Tau (hTau) accumulation and synapse loss are two pathological hallmarks of tauopathies. However, whether and how hTau exerts toxic effects on synapses remain elusive. Mutated hTau (P301S) was ov Show more
Human Tau (hTau) accumulation and synapse loss are two pathological hallmarks of tauopathies. However, whether and how hTau exerts toxic effects on synapses remain elusive. Mutated hTau (P301S) was overexpressed in the N2a cell line, primary hippocampal neurons and hippocampal CA3. Western blotting and quantitative polymerase chain reaction were applied to examine the protein and mRNA levels of synaptic proteins. The protein interaction was tested by co-immunoprecipitation and proximity ligation assays. Memory and emotion status were evaluated by a series of behavioural tests. The transcriptional activity of nuclear factor-erythroid 2-related factor 2 (NRF2) was detected by dual luciferase reporter assay. Electrophoresis mobility shift assay and chromosome immunoprecipitation were conducted to examine the combination of NRF2 to specific anti-oxidative response element (ARE) sequences. Neuronal morphology was analysed after Golgi staining. Overexpressing P301S decreased the protein levels of post-synaptic density protein 93 (PSD93), PSD95 and synapsin 1 (SYN1). Simultaneously, NRF2 was decreased, whereas Kelch-like ECH-associated protein 1 (KEAP1) was elevated. Further, we found that NRF2 could bind to the specific AREs of DLG2, DLG4 and SYN1 genes, which encode PSD93, PSD95 and SYN1, respectively, to promote their expression. Overexpressing NRF2 ameliorated P301S-reduced synaptic proteins and synapse. By means of acetylation at K312, P301S increased the protein level of KEAP1 via inhibiting KEAP1 degradation from ubiquitin-proteasome pathway, thereby decreasing NRF2 and reducing synapse. Blocking the P301S-KEAP1 interaction at K312 rescued the P301S-suppressed expression of synaptic proteins and memory deficits with anxiety efficiently. P301S-hTau could acetylate KEAP1 to trigger synaptic toxicity via inhibiting the NRF2/ARE pathway. These findings provide a novel and potential target for the therapeutic intervention of tauopathies. Show less
Rab21 is a GTPase protein that is functional in intracellular trafficking and involved in the pathologies of many diseases, such as Alzheimer's disease (AD), glioma, cancer, etc. Our previous work has Show more
Rab21 is a GTPase protein that is functional in intracellular trafficking and involved in the pathologies of many diseases, such as Alzheimer's disease (AD), glioma, cancer, etc. Our previous work has reported its interaction with the catalytic subunit of gamma-secretase, PS1, and it regulates the activity of PS1 via transferring it from the early endosome to the late endosome/lysosome. However, it is still unknown how Rab21 protein itself is regulated. This work revealed that Rab21 protein, either endogenously or exogenously, can be degraded by the ubiquitin-proteasome pathway and the autophagy-lysosome pathway. It is further observed that the ubiquitinated Rab21 is increased, but the total protein is unchanged in AD model mice. We further observed that overexpression of Rab21 leads to increased expression of a series of genes involved in the autophagy-lysosome pathway. We speculated that even though the ubiquitinated Rab21 is increased due to the impaired proteasome function in the AD model, the autophagy-lysosome pathway functions in parallel to degrade Rab21 to keep its protein level in homeostasis. In conclusion, understanding the characters of Rab21 protein itself help explore its potential as a target for therapeutic strategy in diseases. Show less
Moderate physical exercise is conducive to the brains of healthy humans and AD patients. Previous reports have suggested that treadmill exercise plays an anti-AD role and improves cognitive ability by Show more
Moderate physical exercise is conducive to the brains of healthy humans and AD patients. Previous reports have suggested that treadmill exercise plays an anti-AD role and improves cognitive ability by promoting amyloid clearance, inhibiting neuronal apoptosis, reducing oxidative stress level, alleviating brain inflammation, and promoting autophagy-lysosome pathway in AD mice. However, few studies have explored the relationships between the ubiquitin-proteasome system and proper exercise in AD. The current study was intended to investigate the mechanism by which the exercise-regulated E3 ubiquitin ligase improves AD. Both wild type and APP/PS1 transgenic mice were divided into sedentary (WTC and ADC) and exercise (WTE and ADE) groups (n = 12 for each group). WTE and ADE mice were subjected to treadmill exercise of 12 weeks in order to assess the effect of treadmill running on learning and memory ability, Aβ plaque burden, hyperphosphorylated Tau protein and E3 ubiquitin ligase. The results indicated that exercise restored learning and memory ability, reduced Aβ plaque areas, inhibited the hyperphosphorylation of Tau protein activated PI3K/Akt/Hsp70 signaling pathway, and improved the function of the ubiquitin-proteasome system (increased UCHL-1 and CHIP levels, decreased BACE1 levels) in APP/PS1 transgenic mice. These findings suggest that exercise may promote the E3 ubiquitin ligase to clear β-amyloid and hyperphosphorylated Tau by activating the PI3K/Akt signaling pathway in the hippocampus of AD mice, which is efficient in ameliorating pathological phenotypes and improving learning and memory ability. Show less
Remyelination is a refractory feature of demyelinating diseases such as multiple sclerosis (MS). Studies have shown that promoting oligodendrocyte precursor cell (OPC) differentiation, which cannot be Show more
Remyelination is a refractory feature of demyelinating diseases such as multiple sclerosis (MS). Studies have shown that promoting oligodendrocyte precursor cell (OPC) differentiation, which cannot be achieved by currently available therapeutic agents, is the key to enhancing remyelination. Bu Shen Yi Sui capsule (BSYSC) is a traditional Chinese herbal medicine over many years of clinical practice. We have found that BSYSC can effectively treat MS. In this study, the effects of BSYSC in promoting OPCs differentiation and remyelination were assessed using an experimental autoimmune encephalomyelitis (EAE) model in vivo and cultured OPCs in vitro. The results showed that BSYSC reduced clinical function scores and increased neuroprotection. The expression of platelet-derived growth factor receptor Show less
Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease, whose etiology is poorly understood. Accumulating evidence indicates that gut microbiota plays an important role in Show more
Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease, whose etiology is poorly understood. Accumulating evidence indicates that gut microbiota plays an important role in the occurrence and progression of various human diseases, including NAFLD. In this study, NAFLD mouse models were established by feeding a high-fat diet (HFD). Baicalein, a natural flavonoid with multiple biological activities, was administered by gavage, and its protective effect on NAFLD was analyzed by histopathological and blood factor analysis. Gut microbiota analysis demonstrated that baicalein could remodel the overall structure of the gut microbiota from NAFLD model mice, especially Show less
Protein complexes mediated by various post-translational modifications (PTMs) play important roles in almost every aspect of biological processes. PTM-mediated protein complexes often have weak and tr Show more
Protein complexes mediated by various post-translational modifications (PTMs) play important roles in almost every aspect of biological processes. PTM-mediated protein complexes often have weak and transient binding properties, which limit their unbiased profiling especially in complex biological samples. Here, we developed a plug-and-play chemical proteomic approach for high-throughput analyis of PTM-mediated protein complexes. Taking advantage of the glutathione-S-transferase (GST) tag, which is the gold standard for protein purification and has wide access to a variety of proteins of interest (POIs), a glutathione (GSH) group- and photo-cross-linking group-containing trifunctional chemical probe was developed to tag POIs and assembled onto a streptavidin-coated 96-well plate for affinity purification, photo-cross-linking, and proteomics sample preparation in a fully integrated manner. Compared with the previously developed photo-pTyr-scaffold strategy, by assembling the tyrosine phosphorylation (pTyr) binding domain through covalent NHS chemistry, the new plug-and-play strategy using a noncovalent GST-GSH interaction has comparable enrichment efficiency for EGF stimulation-dependent pTyr protein complexes. To further prove its feasibility, we additionally assembled four pTyr-binding domains in the 96-well plate and selectively identified their pTyr-dependent interacting proteins. Importantly, we systematically optimized and applied the plug-and-play approach for exploring protein methylation-mediated protein complexes, which are difficult to be characterized due to their weak binding affinity and the lack of efficient enrichment strategies. We explored a comprehensive protein methylation-mediated interaction network assembled by five protein methylation binding domains including the chromo domain of MPP8, tandem tudor domain of KDM4A, full-length CBX1, PHD domain of RAG2, and tandem tudor domain of TP53BP1 and validated the chromo domain- and tudor domain-mediated interaction with histone H3. Collectively, this plug-and-play approach provides a convenient and generic strategy for exploring PTM-dependent protein complexes for any POIs with the GST tag. Show less
This study was designed to evaluate the role and expression of MEK5 signalling in clear cell renal cell carcinoma (ccRCC) and to determine the relevance of MEK5 and mTOR signalling in ccRCC. The expre Show more
This study was designed to evaluate the role and expression of MEK5 signalling in clear cell renal cell carcinoma (ccRCC) and to determine the relevance of MEK5 and mTOR signalling in ccRCC. The expression of MEK5 was compared between ccRCC and normal tissues using the ONCOMINE and TCGA databases. MEK5 expression was evaluated in 14 human ccRCC samples. CCK8, wound-healing, and clone formation assays were performed to examine the cell proliferation, migration, and clone formation abilities of ccRCC cells treated with MEK5 and the inhibitor BIX02189. Furthermore, Western blotting was performed to verify the regulation and influence of MEK5 on the mTOR signalling pathway. Finally, a murine subcutaneous tumour model was constructed, and the effect and safety of BIX02189 were evaluated in vivo. The ONCOMINE and TCGA databases indicated that MEK5 expression in ccRCC was significantly higher than that in normal tissues, which was further confirmed in clinical specimens. MEK5 knockdown markedly inhibited ccRCC cell proliferation, colony formation, and migration, whereas MEK5 overexpression resulted in the opposite results. Western blotting revealed that overexpression of MEK5 could further activate the mTOR signalling pathway. Moreover, the MEK5 inhibitor BIX02189 significantly inhibited cell proliferation, arrested the cell cycle in the G0/G1 phase, induced apoptosis, and effectively inhibited cell migration and clone formation. BIX02189 also showed an excellent antitumor effect and a favourable safety profile in murine models. MEK5 expression was aberrantly increased in ccRCC, which activated the mTOR signalling pathway and regulated cell proliferation, cell cycle progression, migration, and clone formation in ccRCC. Targeted inhibition of MEK5 represents a promising new strategy in patients with ccRCC. Show less
Directed evolution is a widely-used engineering strategy for improving the stabilities or biochemical functions of proteins by repeated rounds of mutation and selection. A protein of interest is selec Show more
Directed evolution is a widely-used engineering strategy for improving the stabilities or biochemical functions of proteins by repeated rounds of mutation and selection. A protein of interest is selected as the template and expressed on a molecular display platform such as a bacteriophage for engineering. Initially, the surface-displayed protein template needs to be checked against the desired target Show less
Alzheimer's disease (AD) is a common neurodegenerative disorder with progressive cognitive impairment in the elderly. Beta-amyloid (Aβ) formation and its accumulation in the brain constitute one of th Show more
Alzheimer's disease (AD) is a common neurodegenerative disorder with progressive cognitive impairment in the elderly. Beta-amyloid (Aβ) formation and its accumulation in the brain constitute one of the pathological hallmarks of AD. Until now, how to modulate Aβ formation in hippocampal neurons remains a big challenge. Herein, we investigated whether the exosomal transfer of microRNA (miR) relates to amyloid pathology in the recipient neuron cells. We isolated circulating small extracellular vesicles (sEVs) from AD patients and healthy controls, determined the miR-342-5p level in the sEVs by RT-PCR, and evaluated its diagnostic performance in AD. Then, we took advantage of biomolecular assays to estimate the role of miR-342-5p in modulating the amyloid pathway, including amyloid precursor protein (APP), beta-site APP cleaving enzyme 1 (BACE1), and Aβ42. Furthermore, we subjected HT22 cells to the sEVs from the hippocampal tissues of transgenic APP mice (Exo-APP) or C57BL/6 littermates (Exo-CTL), and the Exo-APP enriched with miR-342-5p mimics or the control to assess the effect of the sEVs' delivery of miR-342-5p on Aβ formation. We observed a lower level of miR-342-5p in the circulating sEVs from AD patients compared with healthy controls. MiR-342-5p participated in Aβ formation by modulating BACE1 expression, specifically binding its 3'-untranslated region (UTR) sequence. Exo-APP distinctly promoted Aβ42 formation in the recipient cells compared to Exo-CTL. Intriguingly, miR-342-5p enrichment in Exo-APP ameliorated amyloid pathology in the recipient cells. Our study indicated that miR-342-5p was dysregulated in human circulating sEVs from AD patients; sEV transfer of miR-342-5p ameliorates Aβ formation by modulating BACE1 expression. These findings highlight the promising potential of exosomal miRNAs in AD clinical therapy. Show less
Microtubule actin cross-linking factor 1 (MACF1) mutations are known to play an important role in the progression of various cancers. However, its role in breast cancer remains to be determined. In th Show more
Microtubule actin cross-linking factor 1 (MACF1) mutations are known to play an important role in the progression of various cancers. However, its role in breast cancer remains to be determined. In this study, we investigated how MACF1 mutations may play a role in breast cancer development. The gene-expression profile data of patients with breast cancer were obtained from The Cancer Genome Atlas (TCGA)-Breast cancer cohort. We estimated the influence of MACF1 mutations on patient clinical prognosis using the Kaplan-Meier method. Further, patients with MACF1-mutant (MACF1-MT) and MACF1-wild-type (MACF1-WT) were compared to identify the differentially expressed genes (DEGs). We also performed functional enrichment analyses, constructed protein-protein interaction (PPI) and competing endogenous RNA (ceRNA) networks, and investigated the correlation between MACF1 mutations and immune-cell infiltration. To explore the prognostic value of MACF1 mutations, a nomogram was developed based on MACF1 mutations and other clinicopathological parameters. Patients with MACF1-MT had a worse prognosis and higher tumor mutation burden score (P < 0.05) than patients with MACF1-WT. MACF1 mutations were demonstrated to upregulate the mTOR signaling pathway and alter energy metabolism and tumor immune microenvironment. Thus, MACF1 mutations might affect immunogenicity and result in a lower response to immunotherapy. By analyzing the Genomics of Drug Sensitivity in Cancer (GDSC), the sensitivity of breast cancer cells to 13 drugs was found to be significantly enhanced by MACF1 mutations. The prognostic model was verified in predicting the outcome of breast cancer patients. MACF1 mutations might be a potential prognostic biomarker and a therapeutic target for breast cancer. Show less
Non-alcoholic fatty liver disease (NAFLD) is the most common liver disorder with intricate etiology. It is closely associated with metabolic syndrome, insulin resistance and endoplasmic reticulum (ER) Show more
Non-alcoholic fatty liver disease (NAFLD) is the most common liver disorder with intricate etiology. It is closely associated with metabolic syndrome, insulin resistance and endoplasmic reticulum (ER) stress. Exostosin1 (Ext1) is an ER-resident transmembrane glycosyltransferase, which plays an important role in ER homeostasis. Loss-of-function mutations in Ext1 link to hereditary multiple exostosis (HME). The present research was undertaken to identify the effect of Ext1 in the progress of NAFLD. High-fat-diet induced mice obesity, hepatic steatosis and decreased hepatic Ext1 expression. In consistent with evaluation of NAFLD mice possessing down-regulated Ext1 expression, free fatty acid (FFA) treatment blunted Ext1 expression in hepatocytes. In human subjects, HME patients presented elevated fasting blood glucose-one of the criteria that define insulin resistance. In vitro experiments, Ext1 deficiency promoted FFA-induced insulin resistance in hepatocytes by analysis of glycogen storage and hallmarks of gluconeogenesis, ascertaining its association with insulin resistance. Mechanically, Ext1 silencing exacerbated ER stress triggered by FFA, which severely disrupted autophagy in hepatocytes, and thereby accelerated the progression of NAFLD. In conclusion, our study demonstrates a beneficial role for Ext1 during the development of NAFLD, which establishes a novel correlation between Ext1 and ER stress-induced perturbations of autophagy during NAFLD progression. Show less
Glioblastoma (GBM) is the most common primary malignant brain tumor in adults. For patients with GBM, the median overall survival (OS) is 14.6 months and the 5-year survival rate is 7.2%. It is impera Show more
Glioblastoma (GBM) is the most common primary malignant brain tumor in adults. For patients with GBM, the median overall survival (OS) is 14.6 months and the 5-year survival rate is 7.2%. It is imperative to develop a reliable model to predict the survival probability in new GBM patients. To date, most prognostic models for predicting survival in GBM were constructed based on bulk RNA-seq dataset, which failed to accurately reflect the difference between tumor cores and peripheral regions, and thus show low predictive capability. An effective prognostic model is desperately needed in clinical practice. We studied single-cell RNA-seq dataset and The Cancer Genome Atlas-glioblastoma multiforme (TCGA-GBM) dataset to identify differentially expressed genes (DEGs) that impact the OS of GBM patients. We then applied the least absolute shrinkage and selection operator (LASSO) Cox penalized regression analysis to determine the optimal genes to be included in our risk score prognostic model. Then, we used another dataset to test the accuracy of our risk score prognostic model. We identified 2128 DEGs from the single-cell RNA-seq dataset and 6461 DEGs from the bulk RNA-seq dataset. In addition, 896 DEGs associated with the OS of GBM patients were obtained. Five of these genes (LITAF, MTHFD2, NRXN3, OSMR, and RUFY2) were selected to generate a risk score prognostic model. Using training and validation datasets, we found that patients in the low-risk group showed better OS than those in the high-risk group. We validated our risk score model with the training and validating datasets and demonstrated that it can effectively predict the OS of GBM patients. We constructed a novel prognostic model to predict survival in GBM patients by integrating a scRNA-seq dataset and a bulk RNA-seq dataset. Our findings may advance the development of new therapeutic targets and improve clinical outcomes for GBM patients. Show less
Distant metastasis is the major cause of clear cell renal cell carcinoma (ccRCC)-associated mortality. However, molecular mechanisms involved in ccRCC metastasis remain to be fully understood. With th Show more
Distant metastasis is the major cause of clear cell renal cell carcinoma (ccRCC)-associated mortality. However, molecular mechanisms involved in ccRCC metastasis remain to be fully understood. With the increasing appreciation of the role of long non-coding RNAs (lncRNAs) in cancer development, progression, and treatment resistance, the list of aberrantly expressed lncRNAs contributing to ccRCC pathogenesis is expanding rapidly. Bioinformatics analysis was carried out to interrogate publicly available ccRCC datasets. In situ hybridization and qRT-PCR assays were used to test lncRNA expression in human ccRCC tissues and cell lines, respectively. Chromatin immunoprecipitation and luciferase reporter assays were used to examine transcriptional regulation of gene expression. Wound healing as well as transwell migration and invasion assays were employed to monitor ccRCC cell migration and invasion in vitro. ccRCC metastasis was also examined using mouse models in vivo. RNA pulldown and RNA immunoprecipitation were performed to test RNA-protein associations, whereas RNA-RNA interactions were tested using domain-specific chromatin isolation by RNA purification. MILIP expression was upregulated in metastatic compared with primary ccRCC tissues. The increased MILIP expression in metastatic ccRCC cells was driven by the transcription factor AP-2 gamma (TFAP2C). Knockdown of MILIP diminished the potential of ccRCC cell migration and invasion in vitro and reduced the formation of ccRCC metastatic lesions in vivo. The effect of MILIP on ccRCC cells was associated with alterations in the expression of epithelial-to-mesenchymal transition (EMT) hallmark genes. Mechanistically, MILIP formed an RNA-RNA duplex with the snail family transcriptional repressor 1 (Snai1) mRNA and bound to Y-box binding protein 1 (YBX1). This promoted the association between the YBX1 protein and the Snai1 mRNA, leading to increased translation of the latter. Snai1 in turn played an important role in MILIP-driven ccRCC metastasis. The TFAP2C-responsive lncRNA MILIP drives ccRCC metastasis. Targeting MILIP may thus represent a potential avenue for ccRCC treatment. Show less
The Melanocortin-3 receptor (MC3R) and Melanocortin-4 receptor (MC4R), two members of the key hypothalamic neuropeptide signaling, function as complex mediators to control the central appetitive and e Show more
The Melanocortin-3 receptor (MC3R) and Melanocortin-4 receptor (MC4R), two members of the key hypothalamic neuropeptide signaling, function as complex mediators to control the central appetitive and energy homeostasis. The melanocortin 2 receptor accessory protein 2 (MRAP2) is well-known for its modulation on the trafficking and signaling of MC3R and MC4R in mammals. In this study, we cloned and elucidated the pharmacological profiles of MRAP2 on the regulation of central melanocortin signaling in a relatively primitive poikilotherm amphibian species, the Mexican axolotl ( Show less
Triple-negative breast cancer (TNBC) is a highly aggressive type of cancer with few available treatment methods. The aim of the current study was to provide a prognostic autophagy-related gene (ARG) m Show more
Triple-negative breast cancer (TNBC) is a highly aggressive type of cancer with few available treatment methods. The aim of the current study was to provide a prognostic autophagy-related gene (ARG) model to predict the outcomes for TNBC patients using bioinformatic analysis. mRNA expression data and its clinical information for TNBC samples obtained from The Cancer Genome Atlas (TCGA) and Metabric databases were extracted for bioinformatic analysis. Differentially expressed autophagy genes were identified using the Wilcoxon rank sum test in R software. ARGs were downloaded from the Human Autophagy Database. The Kaplan-Meier plotter was employed to determine the prognostic significance of the ARGs. The sample splitting method and Cox regression analysis were employed to establish the risk model and to demonstrate the association between the ARGs and the survival duration. The corresponding ARG-transcription factor interaction network was visualized using the Cytoscape software. A signature-based risk score model was established for eight genes ( An eight-gene autophagic signature model was developed in this study to predict the survival risk for TNBC. The genes identified in the study may favor the design of target agents for autophagy control in advanced TNBC. Show less
The Chromobox (CBX) family members were involved in a variety of physiological and oncological processes through the regulation of the epigenetic modification of chromatin. However, the comprehensive Show more
The Chromobox (CBX) family members were involved in a variety of physiological and oncological processes through the regulation of the epigenetic modification of chromatin. However, the comprehensive analysis of the CBX family in head and neck squamous cell carcinoma (HNSC) is lacking. In this work, we used multiple online databases and tools to investigate the roles of CBX family in aspects of gene expression, prognostic evaluation, genetic alteration, immune micro-environment of tumor, and status of methylation. The mRNA expression levels of CBX1, CBX3, and CBX5 were aberrantly increased in patients with HNSC, while CBX7 was aberrantly decreased. Higher expression of CBX7 was significantly associated with longer OS. Within the 5-11% of genetic alteration rate of CBXs, CBX3 ranked the highest and CBX5/7 ranked the lowest. SPRR1B, S100A7, CASP14, CDSN, LCE3D were the top 5 neighbor genes with the strongest association with CBXs in HNSC patients. Signaling pathways such as epidermal cell differentiation, cornification, and peptide cross-linking were demonstrated to have a strong association with CBX genes. The profiles of immune cell infiltration had high similarity for the group of HNSC patients stratified by expression of CBXs. The methylation levels of CBX1 and CBX5 significantly decreased, while that of CBX7 significantly increased in HNSC samples when compared with normal tissue. In conclusion, the CBX family showed its valuation for further investigation in HNSC. Our research highlighted that CBX7 had the potential to be a novel diagnostic and prognostic biomarker for patients with HNSC. Show less
Arctigenin (Arc) is a phenylpropanoid dibenzylbutyrolactone lignan in Arctium lappa L, which has been widely applied as a traditional Chinese herbal medicine for treating inflammation. In the present Show more
Arctigenin (Arc) is a phenylpropanoid dibenzylbutyrolactone lignan in Arctium lappa L, which has been widely applied as a traditional Chinese herbal medicine for treating inflammation. In the present study, we explored the neuroprotective effect and the potential mechanisms of arctigenin against LPS-evoked neuroinflammation, neurodegeneration, and memory impairments in the mice hippocampus. Daily administration of arctigenin (50 mg/kg per day, i.g.) for 28 days revealed noticeable improvements in spatial learning and memory deficits after exposure to LPS treatment. Arctigenin prevented LPS-induced neuronal/synaptic injury and inhibited the increases in Abeta (Aβ) generation and the levels of amyloid precursor protein (APP) and β-site amyloid precursor protein cleavage enzyme 1 (BACE1). Moreover, arctigenin treatment also suppressed glial activation and reduced the production of proinflammatory cytokines. In LPS-treated BV-2 microglial cells and mice, activation of the TLR4 mediated NF-κB signaling pathway was significantly suppressed by arctigenin administration. Mechanistically, arctigenin reduced the LPS-induced interaction of adiponectin receptor 1 (AdipoR1) with TLR4 and its coreceptor CD14 and inhibited the TLR4-mediated downstream inflammatory response. The outcomes of the current study indicate that arctigenin mitigates LPS-induced apoptotic neurodegeneration, amyloidogenesis and neuroinflammation as well as cognitive impairments, and suggest that arctigenin may be a potential therapeutic candidate for neuroinflammation/neurodegeneration-related diseases. Show less
Histone deacetylases (HDACs) are entwined with the pathogenesis of various cancers and potentially serve as promising therapeutic targets. Herein, we intend to explore the potential role of HDAC1 inhi Show more
Histone deacetylases (HDACs) are entwined with the pathogenesis of various cancers and potentially serve as promising therapeutic targets. Herein, we intend to explore the potential role of HDAC1 inhibitor (JSL-1) in the tumorigenesis and metastasis of cholangiocarcinoma (CC) and to highlight the molecular basis of its function. As shown by bioinformatics analysis and immunohistochemical detection, high HDAC1 expression was witnessed in CC tissues relative to matched controls from patients with cholecystitis. The molecular network that HDAC1 silencing reduced the enrichment of HDAC1 and Snail on the TPX2 promoter was identified using immunoprecipitation and chromatin immunoprecipitation assays. Both short hairpin RNA (shRNA)-mediated knockdown of HDAC1 and JSL-1 treatment exhibited anti-proliferative, anti-migration and anti-invasion effects on CC cells through downregulation of TPX2. The in vivo xenograft model was developed in nude mice. Consistently, the anti-tumorigenic and anti-metastatic properties of shRNA against HDAC1 and HDAC1 inhibitor were validated in the in vivo settings. Taken together, our data supported the notion that HDAC1 inhibitor retards the initiation and development of CC via mediating the TPX2/Snail axis, highlighting the anti-tumor molecular network functioned in CC. Show less
Metastasis is the leading cause of death in patients with colorectal cancer (CRC). The 5-year survival rate of CRC patients in whom the cancer has spread to distant sites is 13.5%. The most common sit Show more
Metastasis is the leading cause of death in patients with colorectal cancer (CRC). The 5-year survival rate of CRC patients in whom the cancer has spread to distant sites is 13.5%. The most common sites of CRC metastasis are liver and lung. The principal therapies for CRC metastatic disease are surgery, but its benefits are limited. This study aimed to reveal the regulatory mechanism of berberine on secondary homing of CRC cells to form metastatic focus. This was more valuable than the previous direct study of the migration and metastasis characteristics of CRC cells. In this study, we used the functional enrichment analysis of differentially expressed genes after berberine treatment and investigated co-expression modules related with CRC metastasis by WGCNA. PPI and survival analyses of significant modules were also conducted. The biological functions of berberine in CRC lung and liver metastasis were investigated by a series of in vitro and in vivo experiments: MTT, colony formation and mouse tail vein injection. And we scanned through the entire extracellular domain of HEY2 protein for autodocking analysis with berberine. We found the differentially expressed genes (DEGs) after berberine treatment were related with cancer progression and metastasis related pathways. Through WGCNA analysis, four cancer progression and metastasis related modules were detected. After PPI and survival analysis, we identified and validated HEY2 as a hub gene, high expression and poor survival at the metastatic stage. Functionally, berberine inhibited the survival, invasion and migration of CRC cells in vitro and in vivo. Mechanistically, berberine treatment down-regulated the expression of HEY2, metastasis related protein E-cadherin, β-catenin and Cyclin D1 during Mesenchymal epithelial transformation (MET). Berberine and HEY2 showed a significant interaction, and berberine binded to HEY2 protein at the residue HIS-99 interface with a hydrogen-bond distance of 1.9A. We revealed that berberine could significantly inhibit the expression of hub gene HEY2 and metastasis related proteins E-cadherin and β-catenin and Cyclin D1 during MET in CRC lung and liver metastases. In total, HEY2 was a promising candidate biomarker for prognosis and molecular characteristics in CRC metastasis. Show less
Developmental dysplasia of the hip (DDH) is a common anomaly leading to adult osteoarthritis. Environmental and genetic factors contribute to DDH, but its exact genetic mechanism is unclear. In this s Show more
Developmental dysplasia of the hip (DDH) is a common anomaly leading to adult osteoarthritis. Environmental and genetic factors contribute to DDH, but its exact genetic mechanism is unclear. In this study, we used whole exome sequencing to identify the causative gene of a DDH pedigree. A rare missense variant in KANSL1 (c.C767T; p.S256F) was identified as the pathogenic cause of DDH. Subsequent mutation screening showed another missense variant in 1 of 200 sporadic patients. Kansl1-mutated mice showed reduced chondrocytes in the acetabulum and a decrease in the cartilage matrix, which may be DDH phenotype-related abnormalities. Furthermore, functional studies showed that cell proliferation was delayed and Mmp13 expression was abnormally upregulated in chondrocytes differentiated from Kansl1 mutant mouse embryonic stem cells. In conclusion, our findings suggest that KANSL1 is a novel pathogenic gene for DDH. The identification of KANSL1 variants has great diagnostic value for identifying individuals with DDH. KEY MESSAGES: Developmental dysplasia of the hip (DDH) is a common anomaly causing adult osteoarthritis. Environmental and genetic factors contribute to DDH, but its exact genetic mechanism is unclear. Using high-throughput whole exome sequencing, we found a novel variant in KANSL1 that was co-inherited by all severely affected individuals diagnosed with DDH from a three-generation family. Further analysis revealed that a Kansl1 variant in mice reduced the number of chondrocytes and decreased cartilage matrix, and mouse embryonic stem differentiation assay showed cartilage defects. These findings indicate a direct association between KANSL1 and hip development, expanding the pathogenic gene spectrum in DDH and providing insight into potential new targets for diagnosing and treating hip dysplasia. Show less
The epithelial-mesenchymal transition (EMT) is an important pathological process in the occurrence of pulmonary fibrosis. Changes in histone methylation modifications of key genes play an important ro Show more
The epithelial-mesenchymal transition (EMT) is an important pathological process in the occurrence of pulmonary fibrosis. Changes in histone methylation modifications of key genes play an important role in this process. As a histone methyltransferase, the regulatory mechanism and role of SET domain bifurcated 1 (SETDB1) in pulmonary fibrosis remain unclear. We found that SETDB1 inhibited EMT and that cells attenuated the expression of SETDB1 to relieve this inhibition during transforming growth factor-β (TGF-β)-induced EMT. Silencing SETDB1 expression significantly enhanced the mesenchymal phenotype induced by TGF-β and the expression and deposition of fibronectin and significantly reduced the expression of E-cadherin. The decrease in E-cadherin expression and the induction of EMT led to increased lipid reactive oxygen species (ROS) and ferrous ions, which induced ferroptosis. Chromatin immunoprecipitation (ChIP) results showed that SETDB1 regulates the expression of Snai1 by catalyzing the histone H3 lysine 9 trimethylation (H3K9me3) of Snai1, the main transcription factor that initiates the process of EMT, and thus, indirectly regulates E-cadherin. Surprisingly, when examining the effect of overexpressed SETDB1 on EMT, we found that overexpressed SETDB1 alleviated EMT and also caused ferroptosis. We suggest that the overexpression of SETDB1 partially reverses the mesenchymal phenotype to an epithelial state, while those cells that fail to reverse are depleted by ferroptosis. In conclusion, the histone methylase SETDB1 regulates Snai1 epigenetically, driving EMT gene reprogramming and ferroptosis in response to TGF-β. However, there are unexplored links between the epigenetic reprogramming and transcriptional processes that regulate EMT in a TGF-β-dependent manner. Show less
Esophageal squamous cell carcinoma (ESCC) is one of the most common cancers worldwide, with high incidence and mortality rates and low survival rates. However, the detailed molecular mechanism of ESCC Show more
Esophageal squamous cell carcinoma (ESCC) is one of the most common cancers worldwide, with high incidence and mortality rates and low survival rates. However, the detailed molecular mechanism of ESCC progression remains unclear. Here, we first showed significantly higher WNT5A and SNAIL expression in ESCC samples than in corresponding paracancerous samples. High WNT5A and SNAIL expression levels correlated positively with lymphatic metastasis and poor prognosis for patients with ESCC based on immunohistochemical (IHC) staining of 145 paired ESCC samples. Spearman's correlation analyses confirmed the strong positive correlation between WNT5A and SNAIL expression, and patients with ESCC presenting coexpression of WNT5A and SNAIL had the worst prognosis. Then, we verified that the upregulation of WNT5A promoted ESCC cell metastasis in vivo and in vitro, suggesting that WNT5A might be a promising therapeutic target for the prevention of ESCC. Furthermore, WNT5A overexpression induced the epithelial-mesenchymal transition via histone deacetylase 7 (HDAC7) upregulation, and HDAC7 silencing significantly reversed WNT5A-induced SNAIL upregulation and ESCC cell metastasis. In addition, we used HDAC7 inhibitors (SAHA and TMP269) to further confirm that HDAC7 participates in WNT5A-mediated carcinogenesis. Based on these results, HDAC7 is involved in WNT5A-mediated ESCC progression, and approaches targeting WNT5A and HDAC7 might be potential therapeutic strategies for ESCC. Show less
Differentiation blockade is a hallmark of acute myeloid leukemia (AML). A strategy to overcome such a blockade is a promising approach against the disease. The lack of understanding of the underlying Show more
Differentiation blockade is a hallmark of acute myeloid leukemia (AML). A strategy to overcome such a blockade is a promising approach against the disease. The lack of understanding of the underlying mechanisms hampers development of such strategies. Dysregulated ribonucleotide reductase (RNR) is considered a druggable target in proliferative cancers susceptible to deoxynucleoside triphosphate (dNTP) depletion. Herein, we report an unanticipated discovery that hyperactivating RNR enables differentiation and decreases leukemia cell growth. We integrate pharmacogenomics and metabolomics analyses to identify that pharmacologically (eg, nelarabine) or genetically upregulating RNR subunit M2 (RRM2) creates a dNTP pool imbalance and overcomes differentiation arrest. Moreover, R-loop-mediated DNA replication stress signaling is responsible for RRM2 activation by nelarabine treatment. Further aggravating dNTP imbalance by depleting the dNTP hydrolase SAM domain and HD domain-containing protein 1 (SAMHD1) enhances ablation of leukemia stem cells by RRM2 hyperactivation. Mechanistically, excessive activation of extracellular signal-regulated kinase (ERK) signaling downstream of the imbalance contributes to cellular outcomes of RNR hyperactivation. A CRISPR screen identifies a synthetic lethal interaction between loss of DUSP6, an ERK-negative regulator, and nelarabine treatment. These data demonstrate that dNTP homeostasis governs leukemia maintenance, and a combination of DUSP inhibition and nelarabine represents a therapeutic strategy. Show less
As a member of the PIKs family, PIK3C3 participates in autophagy and plays a central role in liver function. Several studies demonstrated that the complete suppression of PIK3C3 in mammals can cause h Show more
As a member of the PIKs family, PIK3C3 participates in autophagy and plays a central role in liver function. Several studies demonstrated that the complete suppression of PIK3C3 in mammals can cause hepatomegaly and hepatosteatosis. However, the function of PIK3C3 overexpression on the liver and other organs is still unknown. In this study, we successfully generated PIK3C3 transgenic pigs through somatic cell nuclear transfer (SCNT) by designing a specific vector for the overexpression of PIK3C3. Plasmid identification was performed through enzyme digestion and transfected into the fetal fibroblasts derived from Show less
The single nucleotide polymorphisms (SNPs) in the fatty acid desaturases and elongases might associate with the endogenous synthesis of polyunsaturated fatty acids (PUFAs). However, the related epidem Show more
The single nucleotide polymorphisms (SNPs) in the fatty acid desaturases and elongases might associate with the endogenous synthesis of polyunsaturated fatty acids (PUFAs). However, the related epidemiological evidence is still conflicting. So we aimed to clearly evaluate the interactions between maternal DHA-rich n-3 PUFAs supplementation and the known 26 SNPs on the profiles of PUFAs in the colostrum using a Chinese birth cohort. Totally, 1050 healthy mother-infant pairs were enrolled in this study at gestational 6-8 weeks when they established their pregnancy files at Fuxing Hospital affiliated to Capital Medical University in Beijing from January to December 2018. Meanwhile, their venous blood samples were obtained for DNA extraction to detect the genotypes of SNPs in the Fads1, Fads2, Fads3, Elovl2 and Elovl5 using the Matrix-Assisted Laser Desorption Ionization Time of Flight Mass Spectrometry. Then the colostrum samples were collected to determine the profiles of PUFAs by gas chromatography. Maternal DHA-rich n-3 PUFAs supplementation from the early and middle pregnancy could reduce the infant BMI at birth, and impact the profiles of PUFAs in the colostrum, as higher n-3 PUFAs (EPA, DHA, DHA/ALA and DHA/EPA), lower n-6 PUFAs (AA and AA/LA) and ∑-6/n-3ΣPUFAs. Moreover, there were significant correlations between multiple SNPs and the profiles of n-6 PUFAs (rs76996928 for LA, rs174550, rs174553 and rs174609 for AA, rs174550 and rs76996928 for AA/LA) and n-3 PUFAs in the colostrum (rs174448, rs174537, rs174550, rs174553, rs174598, rs3168072, rs174455 and rs174464 for ALA, rs174550, rs174553 and rs174598 for EPA, rs174455 and rs174464 for DHA, rs174448 and rs3168072 for DHA/EPA) using the multiple linear regressions by adjusting the maternal age, gestational week, mode of delivery, infant sex and BMI at birth, and all these above significant SNPs had the cumulative effects on the profiles of PUFAs. Furthermore, the pairwise comparisons also showed the meaningful interactions between maternal DHA-rich n-3 PUFAs supplementation and related genotypes of SNPs (rs76996928 for LA, rs174598 for EPA, rs174448 for DHA and DHA/EPA) on the contents of PUFAs in the colostrum. Results from this birth cohort study proved that the pregnant women with the following SNPs such as Fads3 rs174455 T, Fads3 rs174464 A and Fads1 rs174448 G alleles should pay more attention on their exogenous DHA supplementation from the early and middle pregnancy for the blocked endogenous synthesis. This study was approved by the Ethics Committee of Beijing Pediatric Research Institution, Beijing Children's Hospital affiliated to Capital Medical University (2016-08), which was also registered at the website of http://www.chictr.org.cn/showproj.aspx?proj=4673 (No: ChiCTR-OCH-14004900). Show less
S-adenosyl-l-homocysteine (SAH), an amino acid derivative, is a key intermediate metabolite in methionine metabolism, which is normally considered as a harmful by-product and hydrolyzed quickly once f Show more
S-adenosyl-l-homocysteine (SAH), an amino acid derivative, is a key intermediate metabolite in methionine metabolism, which is normally considered as a harmful by-product and hydrolyzed quickly once formed. AHCY (adenosylhomocysteinase) converts SAH into homocysteine and adenosine. There are two other members in the AHCY family, AHCYL1 (adenosylhomocysteinase like 1) and AHCYL2 (adenosylhomocysteinase like 2). Here we define AHCYL1 function as a SAH sensor to inhibit macroautophagy/autophagy through PIK3C3. The C terminus of AHCYL1 interacts with SAH specifically and the interaction with SAH promotes the binding of the N terminus to the catalytic domain of PIK3C3, resulting in inhibition of PIK3C3. More importantly, this observation was further validated Show less
Depolarized mitochondria can be degraded via mitophagy, a selective form of autophagy. The RAB GTPase RAB7A was recently shown to play a key role in this process. RAB7A regulates late endocytic traffi Show more
Depolarized mitochondria can be degraded via mitophagy, a selective form of autophagy. The RAB GTPase RAB7A was recently shown to play a key role in this process. RAB7A regulates late endocytic trafficking under normal growth conditions but is translocated to the mitochondrial surface following depolarization. However, how RAB7A activity is regulated during mitophagy is not understood. Here, using a proximity-dependent biotinylation approach (miniTurbo), we identified C5orf51 as a specific interactor of GDP-locked RAB7A. C5orf51 also interacts with the RAB7A guanine nucleotide exchange factor (GEF) complex members MON1 and CCZ1. In the absence of C5orf51, localization of RAB7A on depolarized mitochondria is compromised and the protein is degraded by the proteasome. Furthermore, depletion of C5orf51 also inhibited ATG9A recruitment to depolarized mitochondria. Together, these results indicate that C5orf51 is a positive regulator of RAB7A in its shuttling between late endosomes and mitochondria to enable mitophagy. Show less