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Recent findings suggest that extracellular heat shock protein 90α (eHSP90α) promotes pulmonary fibrosis, but the underlying mechanisms are not well understood. Aging, especially cellular senescence, is a critical risk factor for idiopathic pulmonary fibrosis (IPF). Here, we aim to investigate the role of eHSP90α on cellular senescence in IPF. Our results found that eHSP90α was upregulated in bleomycin (BLM)-induced mice, which correlated with the expression of senescence markers. This increase in eHSP90α mediated fibroblast senescence and facilitated mitochondrial dysfunction. eHSP90α activated TGF-β signaling through the phosphorylation of the SMAD complex. The SMAD complex binding to p53 and p21 promoters triggered their transcription. In vivo, the blockade of eHSP90α with 1G6-D7, a specific eHSP90α antibody, in old mice attenuated the BLM-induced lung fibrosis. Our findings elucidate a crucial mechanism underlying eHSP90α-induced cellular senescence, providing a framework for aging-related fibrosis interventions.

Non-small cell lung cancer (NSCLC) is the most common subtype of lung cancer with the high morbidity and mortality in the world. Meanwhile, the acquired drug resistance against EGFR-mutated NSCLC is increasingly serious. HSP90α might play critical roles in NSCLC, but the effect of GW4869 on extracellular HSP90α remains unclear. We collected plasma samples from 22 NSCLC and 10 healthy individuals, and measured the plasma HSP90α levels by ELISA. Western blot was used to detect the levels of HSP90α, E-cadherin, N-cadherin, and Vimentin in HCC827 and PC9 cells. We found that extracellular HSP90α was upregulated in NSCLC mutated patients and accelerated epithelial-mesenchymal transition (EMT) and invasion/migration capacity in EGFR-mutated NSCLC cells. Meanwhile, we also confirmed that GW4869 inhibited the expression of eHSP90α, EMT and invasion/migration abilities in HCC827 and PC9, and enhanced the antitumor activity of gefitinib in BALB/C nude mice in vivo. These studies suggest that GW4869 can inhibit epithelial-mesenchymal transition promoted by extracellular HSP90α in non-small cell lung cancer, which provides new strategies for delaying the development of acquired resistance to gefitinib for EGFR-mutated NSCLC.

Non-small cell lung cancer (NSCLC) is the most common subtype of lung cancer in the world. Extracellular HSP90α (eHSP90α) promotes epithelial–mesenchymal transition (EMT) and leads to NSCLC resistance in combination with targeted drugs. However, the molecular mechanism by which HSP90α induces EMT is unclear.Here, we used the STRING database to screen for proteins that interact with HSP90α in lung cancer cells, and found that the relationship between HSP90α and GPX4 is essential for ferroptosis in NSCLC cells. We also found that extracellular HSP90α increased E-cadherin expression by silencing LRP1 with siRNA, while decreased N-cadherin, Vimentin, and GPX4 expression, eHSP90α promoted EMT and inhibited ferroptosis by upregulating GPX4. We further found that hrHSP90α and TGF-β1 inhibited ferroptosis.The AKT signaling pathway was involved in eHSP90α-inhibited EMT. Meanwhile, we also confirmed that Ferrostatin-1 and hrHSP90α accelerated gefitinib resistance.These findings suggest that eHSP90α promoted EMT through LRP1 and inhibited ferroptosis by upregulating GPX4 in NSCLC cells. There may be mutual regulation between EMT and ferroptosis, and ferroptosis-inducing therapy may provide a new treatment strategy for gefitinib-resistant NSCLC.

Asthma is a disease characterized by airway epithelial barrier destruction, chronic airway inflammation, and airway remodeling. Repeated damage to airway epithelial cells by allergens in the environment plays an important role in the pathophysiology of asthma. Ferroptosis is a novel form of regulated cell death mediated by lipid peroxidation in association with free iron-mediated Fenton reactions. In this study, we explored the contribution of ferroptosis to house dust mite (HDM)-induced asthma models. Our in vivo and in vitro models showed labile iron accumulation and enhanced lipid peroxidation with concomitant nonapoptotic cell death upon HDM exposure. Treatment with ferroptosis inhibitors deferoxamine (DFO) and ferrostatin-1 (Fer-1) illuminated the role of ferroptosis and related damage-associated molecular patterns in HDM-treated airway epithelial cells. Furthermore, DFO and Fer-1 reduced HDM-induced airway inflammation in model mice. Mechanistically, NCOA4-mediated ferritin-selective autophagy (ferritinophagy) was initiated during ferritin degradation in response to HDM exposure. Together, these data suggest that ferroptosis plays an important role in HDM-induced asthma and that ferroptosis may be a potential treatment target for HDM-induced asthma.

Background Up-regulation of aerobic glycolysis has been reported as a characterization of asthma and facilitates airway inflammation. We has been previously reported that short isoform thymic stromal lymphopoietin (sTSLP) could reduce inflammation in asthmatic airway epithelial cells. Here we wanted to investigate whether the inhibition of sTSLP on asthma is related to aerobic glycolysis. Methods Asthmatic model was established in challenging Male BALB/c mice and 16-HBE (human bronchial epithelial) cell line with house dust mite (HDM). Indicators of glycolysis were assessed to measure whether involve in sTSLP regulating airway epithelial cells inflammation in asthmatic model in vivo and in vitro. Results sTSLP decreased inflammation of asthmatic airway and aerobic glycolysis in mice. HDM or long isoform thymic stromal lymphopoietin (lTSLP) promoted HIF-1α expression and aerobic glycolysis by miR-223 to target and inhibit VHL (von Hippel-Lindau) expression 16-HBE. Inhibition of aerobic glycolysis restrained HDM- and lTSLP-induced inflammatory cytokines production. sTSLP along had almost no potential to alter aerobic glycolysis of 16-HBE. But sTSLP decreased LDHA (lactate dehydrogenase A) and LD (Lactic acid) levels in BALF, and HIF-1α and LDHA protein levels in airway epithelial cells of asthma mice model. lTSLP and sTSLP both induced formation of TSLPR and IL-7R receptor complex, and lTSLP obviously facilitated phosphorylation of JAK1, JAK2 and STAT5, while sTSLP induced a little phosphorylation of JAK1 and STAT5. Conclusion We identified a novel mechanism that lTSLP could promote inflammatory cytokines production by miR-223/VHL/HIF-1α pathway to upregulate aerobic glycolysis in airway epithelial cells in asthma. This pathway is suppressed by sTSLP through occupying binding site of lTSLP in TSLPR and IL-7R receptor complex.

Background: Accumulating studies have suggested the airway microbiota of lung cancer was significantly different from healthy controls. However, little was known about the relationship between airway microbiota and important clinical parameters of lung cancer. In this study, we aimed to explore the association between sputum microbiota and lung cancer stage, lymph node metastasis, intrathoracic metastasis, and Epidermal growth factor receptor (EGFR) gene mutation. Methods: The microbiota of sputum samples from 85 newly diagnosed NSCLC patients were sequenced via 16S rRNA sequencing with V3-V4 region. Sequencing reads were filtered using QIIME2 and clustered against UPARSE. Results: The α diversity and β diversity was significantly different between patients in stage I to II (early stage, ES) and patients in stage III to IV (advanced stage, AS). Lefse identified that genera Granulicatella and Actinobacillus were significantly enriched in ES, and genus Actinomyces were significantly enriched in AS. PICRUSt2 identified NAD salvage pathway was significantly enriched in AS, which was positively associated with Granulicatella. Patients with intrathoracic metastasis were associated with increased genus Peptostreptococcus and incomplete reductive TCA cycle, which was associated with increased Peptostreptococcus. Genera Parvimonas, Pseudomona and L-valine biosynthesis were positively associated with lymph node metastasis. L-valine biosynthesis was related with increased Pseudomona. Finally, genus Parvimonas were significantly upregulated in adenocarcinoma patients with EGFR mutation. Conclusion: Taxonomy structure differed between different lung cancer stage. The tumor stage, intrathoracic metastasis, lymph node metastasis, and EGFR mutation were associated with alteration of specific airway genera and metabolic function of sputum microbiota.

Idiopathic pulmonary fibrosis (IPF) is a fatal disease in which the normal alveolar network is gradually replaced by fibrotic scars. Current evidence suggests that metabolic alterations correlate with myofibroblast activation in IPF. Anlotinib has been proposed to have antifibrotic effects, but the efficacy and mechanisms of anlotinib against lung fibrosis have not been systematically evaluated. The antifibrotic effects of anlotinib were evaluated in bleomycin-induced mouse models and transforming growth factor-beta 1 (TGF-β1)-stimulated lung fibroblasts. We measured lactate levels, 2-NBDG glucose uptake and the extracellular acidification rate (ECAR) to assess glycolysis in fibroblasts. RNA-protein coimmunoprecipitation (RIP) and polysome analyses were performed to investigate novel mechanisms of glycolytic reprogramming in pulmonary fibrosis. We found that anlotinib diminished myofibroblast activation and inhibited the augmentation of glycolysis. Moreover, we show that PCBP3 posttranscriptionally increases PFKFB3 expression by promoting its translation during myofibroblast activation, thus promoting glycolysis in myofibroblasts. Regarding mechanism, anlotinib exerts potent antifibrotic effects by downregulating PCBP3, reducing PFKFB3 translation and inhibiting glycolysis in myofibroblasts. Furthermore, we observed that anlotinib had preventative and therapeutic antifibrotic effects on bleomycin-induced pulmonary fibrosis. Therefore, we identify PCBP3 as a protein involved in the regulation of glycolysis reprogramming and lung fibrogenesis and propose it as a therapeutic target for pulmonary fibrosis. Our data suggest that anlotinib has antifibrotic effects on the lungs, and we provide a novel mechanism for this effect. Anlotinib may constitute a novel and potent candidate for the treatment of pulmonary fibrosis.

Background Exposure to toluene diisocyanate (TDI) is a significant pathogenic factor for asthma. We previously reported that the receptor for advanced glycation end products (RAGE) plays a key role in TDI-induced asthma. Histone deacetylase (HDAC) has been reported to be important in asthmatic pathogenesis. However, its effect on TDI-induced asthma is not known. The aim of this study was to determine the role of RAGE and HDAC in regulating airway inflammation using a TDI-induced murine asthma model. Methods BALB/c mice were sensitized and challenged with TDI to establish an asthma model. FPS-ZM1 (RAGE inhibitor), JNJ-26482585 and romidepsin (HDAC inhibitors) were administered intraperitoneally before each challenge. In vitro, the human bronchial epithelial cell line 16HBE was stimulated with TDI-human serum albumin (TDI-HSA). RAGE knockdown cells were constructed and evaluated, and MK2006 (AKT inhibitor) was also used in the experiments. Results In TDI-induced asthmatic mice, the expression of RAGE, HDAC1, and p-AKT/t-AKT was upregulated, and these expressions were attenuated by FPS-ZM1. Airway reactivity, Th2 cytokine levels in lymph supernatant, IgE, airway inflammation, and goblet cell metaplasia were significantly increased in the TDI-induced asthmatic mice. These increases were suppressed by JNJ-26482585 and romidepsin. In addition, JNJ-26482585 and romidepsin ameliorated the redistribution of E-cadherin and β-catenin in TDI-induced asthma. In TDI-HSA-stimulated 16HBE cells, knockdown of RAGE attenuated the upregulation of HDAC1 and phospho-AKT (p-AKT). Treatment with the AKT inhibitor MK2006 suppressed TDI-induced HDAC1 expression. Conclusions These findings indicate that RAGE modulates HDAC1 expression via the PI3K/AKT pathway, and that inhibition of HDAC prevents TDI-induced airway inflammation.

Background: Accumulating studies have suggested the airway microbiota of lung cancer was significantly different from healthy controls. However, little was known about the relationship between airway microbiota and important clinical parameters of lung cancer. In this study, we aimed to explore the association between sputum microbiota and lung cancer stage, lymph node metastasis, intrathoracic metastasis, and Epidermal growth factor receptor (EGFR) gene mutation. Methods: The microbiota of sputum samples from 85 newly diagnosed NSCLC patients were sequenced via 16S rRNA sequencing with V3-V4 region. Sequencing reads were filtered using QIIME2 and clustered against UPARSE. Results: The α diversity and β diversity was significantly different between patients in stage I to II (early stage, ES) and patients in stage III to IV (advanced stage, AS). Lefse identified that genera Granulicatella and Actinobacillus were significantly enriched in ES, and genus Actinomyces were significantly enriched in AS. PICRUSt2 identified NAD salvage pathway was significantly enriched in AS, which was positively associated with Granulicatella. Patients with intrathoracic metastasis were associated with increased genus Peptostreptococcus and incomplete reductive TCA cycle. Enrichment of TCA cycle was associated with increased Peptostreptococcus. Genera Parvimonas, Pseudomona and L-valine biosynthesis were positively associated with lymph node metastasis. L-valine biosynthesis was related with increased Pseudomona. Finally, genus Parvimonas were significantly upregulated in adenocarcinoma patients with EGFR mutation. Conclusion: In conclusion, the taxonomy structure differed between different lung cancer stage. The tumor stage, intrathoracic 1 metastasis, lymph node metastasis, and EGFR mutation were associated with alteration of specific airway genera and metabolic function of sputum microbiota.

Pulmonary fibrosis is characterized by alveolar epithelial cell injury, lung fibroblast proliferation, differentiation, and extracellular matrix (ECM) deposition. Our previous study indicated that extracellular HSP90α (eHSP90α) promotes pulmonary fibrosis by activating the MAPK signaling pathway. Thus, treatment with 1G6-D7 (a selective HSP90α monoclonal antibody) to antagonize eHSP90α could effectively ameliorate fibrosis. This study aimed to elucidate the mechanism underlying the effects of eHSP90α in pulmonary fibrosis by focusing on its link with endoplasmic reticulum (ER) stress. Our results showed that eHSP90α promoted lung fibroblast differentiation by activating ER stress. Treatment with the ER stress inhibitor tauroursodeoxycholate (TUDCA) or glucose-regulated protein 78 kDa (GRP78) depletion significantly abrogated the effect of eHSP90α on ER stress and fibroblast activation. In addition, eHSP90α induced ER stress in fibroblasts via the phosphoinositide-4,5-bisphosphate 3-kinase (PI3K)-protein kinase B (AKT) signaling pathway, which could be blocked by the PI3K/AKT inhibitor LY294002, and blockade of eHSP90α by 1G6-D7 markedly inhibited ER stress in the model, indicating preventive and therapeutic applications. Intriguingly, we observed that TUDCA effectively reduced the secretion of eHSP90α in vitro and in vivo. In conclusion, this study shows that the interaction between eHSP90α and ER stress plays a crucial role in pulmonary fibrosis, indicating a positive feedback in lung fibroblasts. Targeting eHSP90α and alleviating fibroblast ER stress may be promising therapeutic approaches for pulmonary fibrosis.

Background: The prevalence of adult asthma is increasing in China. However, there are no large sample, epidemiological data describing asthma severity at the time of new diagnosis and changes during follow-up management. Thus, the purpose of this study was to use a large health care database to examine asthma severity at initial diagnosis, and changes in severity over the first year of management.Methods: Data of patients with a first diagnosis of asthma were extracted from the SuValue electronic medical database. Inclusion criteria were: 1) At least 14 years old at the time of first diagnosis; 2) Initial diagnosis from 2001 to March 2019; 3) Followed-up for at least 12 months; 4) Had a follow-up visit every 3 months. Disease severity at diagnosis and at each follow-up visit, medications prescribed, and symptoms were collected and analysed.Results: A total of 7,654 adult patients with newly diagnosed asthma from tertiary hospitals (26.38%) and secondary hospitals (73.62%) who were followed-up for at least 12 months were included. Approximately 54% were females, and the proportion of patients over 60 years old was the highest (38%). Of all patients, 53.91% were not prescribed medications to control asthma, suggesting that these patients were mild asthma. Approximately 16% of patients were prescribed oral corticosteroid and/or inhaled corticosteroid and long-acting β2-agonist combination, suggesting moderate to severe asthma. The proportions of patients with moderate and severe decreased during the first 6 months, and then the proportions remained stable. The proportion of patients with severe asthma remained stable from the 6th month onward. At the end of the year 2.7% of patients had severe asthma. Patients with mild asthma tended to continue to have mild asthma in the following 3 months (> 76.19%). However, of the patients with mild and moderate asthma at 3 months, 92.85% and 75.1%, respectively, had a reduction in severity and had mild asthma at 12 months. On the other hand, 1.26% and 3.15%, respectively, progressed to severe asthma by 12 months.Conclusion: During the first year after an initial diagnosis of asthma patients diagnosed with mild asthma tended to not progress and remained stable with mild asthma over the year. The proportions of patients diagnosed with moderate and severe asthma remained stable over the year. Further study is needed to examine the clinical features of newly diagnosed patients with severe asthma who do not experience a reduction in severity in order to target these patients for more intensive treatment and reduce the disease burden.

Idiopathic pulmonary fibrosis is a progressive fatal disease characterized by interstitial remodeling, with high lethality and a lack of effective medical therapies. Tetrandrine has been proposed to present anti-fibrotic effects, but the efficacy and mechanisms have not been systematically evaluated. We sought to study the potential therapeutic effects and mechanisms of tetrandrine against lung fibrosis. The anti-fibrotic effects of tetrandrine were evaluated in bleomycin-induced mouse models and TGF-β1-stimulated murine lung fibroblasts. We performed Chromatin Immunoprecipitation (ChIP), Immunoprecipitation (IP), and mRFP-GFP-MAP1LC3B adenovirus construct to investigate the novel mechanisms of tetrandrine-induced autophagy. Tetrandrine decreased TGF-β1-induced expression of α-smooth muscle actin, fibronectin, vimentin, and type 1 collagen and proliferation in fibroblasts. Tetrandrine restored TGF-β1-induced impaired autophagy flux, accompanied by enhanced interaction of SQSTM1 and MAP1LC3-Ⅱ. ChIP studies revealed that tetrandrine induced autophagy via increasing binding of NRF2 and SQSTM1 promoter. Furthermore, tetrandrine inhibited TGF-β1-induced phosphorylation of mTOR by reducing activation of Rheb. In vivo tetrandrine suppressed the bleomycin-induced expression of fibrotic markers and improved pulmonary function. Our data suggest that protective effect of tetrandrine against lung fibrosis might be through promoting Rheb-mTOR and NRF2-SQSTM1 mediated autophagy. Tetrandrine may thus be potentially employed as a novel therapeutic medicine against IPF.

BACKGROUND: Exacerbations are recognized as the most relevant predictor of future risk in asthmatics. We aimed to evaluate the association between asthma exacerbations, fractional exhaled nitric oxide (FENO), spirometry indices, and other potential risk factors in a non-interventional, real-world study performed in Guangzhou, China. METHODS: We performed a prospective 12 months follow-up of Chinese asthmatics. Spirometry and FENO measurements were performed at baseline. Adherence to inhaled corticosteroids (ICS) use was divided into two categories (>80% and 0.05) between the groups. There was also no significant difference in FENO level between the two groups. Compared to those that had exacerbations, patients without exacerbations had better treatment compliance (P

Background: Atherosclerosis is the main pathological change in diabetic angiopathy, and vascular inflammation plays an important role in early atherosclerosis. Heat shock protein 90, a cellular molecular chaperone, was recently determined to be secreted extracellularly, but the specific mechanism remains unclear. This study explored the relationship between Hsp90 and diabetic peripheral artery disease through serological analyses of different groups of diabetic patients and investigated the relationship between extracellular Hsp90α and vascular inflammation at the cellular level.Methods: Seventy-seven selected patients were divided into three groups. The relationships among serum Hsp90, oxidative stress indexes and patient outcomes and the correlations among the indexes were analysed. An oxidative stress endothelial injury model was established under high glucose in vitro to explore the role of eHsp90 release in atherosclerosis progression.Results: Serum Hsp90 and MDA levels tended to increase in different groups with peripheral vascular disease aggravation. Hsp90α was correlated with MDA to some extent and was predictive. In vitro, high glucose and low H2O2 treatment increased extracellular Hsp90 secretion, and endothelial cell conditioned medium and recombinant human Hsp90α increased monocyte migration (PConclusions: Extracellular Hsp90α participates in endothelial cell injury in diabetic vascular disease and initiates the inflammatory response by promoting monocyte migration.Trial registration: NCT04787770, ClinicalTrials.gov, Registered 9 March, 2021 - Prospective registered

RationaleThymic stromal lymphopoietin (TSLP) is present in two distinct isoforms, short-form (sfTSLP) and long-form (lfTSLP). lfTSLP promotes inflammation while sfTSLP inhibits inflammation in allergic asthma. However, little is known about the regulation of lfTSLP and sfTSLP during allergic attack in asthma airway epithelium.Methods and ResultsHere, we report that SUMOylation was enhanced in HDM-induced allergic asthma airway epithelium. Inhibition of SUMOylation significantly alleviated airway Th2 inflammation and lfTSLP expression. Mechanistically, CBX4, a SUMOylation E3 ligase, enhanced lfTSLP, but not sfTSLP, mRNA translation through the RNA binding protein, MEX-3B. MEX-3B promoted lfTSLP translation through binding of its KH domains to the lfTSLP mRNA. Furthermore, CBX4 regulated MEX-3B transcription in HBE through enhancing SUMOylation levels of the transcription factor, TFII-I.ConclusionWe demonstrate an important mechanism whereby CBX4 promotes MEX-3B transcription through enhancing TFII-I SUMOylation, and MEX-3B enhances the expression of lfTSLP through binding to the lfTSLP mRNA and promoting its translation. Our findings uncover a novel target of CBX4 for therapeutic agents to lfTSLP-mediated asthma.

Background: Asthma is prevalent but largely undiagnosed and undertreated in China. Despite readily available effective therapies, the outcomes still leave much to be desired. There is a scarcity of data describing the treatment patterns of patients with newly diagnosed asthma in real world settings. The main goal of this study was to investigate treatment patterns of newly diagnosed asthma patients with up to 1 year follow-up to gain a better understanding of gaps of optimal asthma management in China.Methods: We conducted a large-scale of retrospective cohort analysis of asthma treatment for newly diagnosed patients using an electronic medical record database (SuValue). Eligible patients were at least 14 years old at the diagnosis from 2001 to March 2019. We categorized anti-asthmatic medication use by its classes and documented their use by the underlying disease severity. To examine the use of controlled medications over follow-ups, we summarized their utilization over consecutive 3-month time windows from the initial diagnosis to the end of follow-up. Results: A total of 26,301 patients from tertiary (25.24%), secondary (71.83%) and primary (2.92%) hospitals were included in the study; 54.01% received one or more controller medications during the study period and 30.4% had 12 months of follow-up visits. Initial prescriptions were inhaled corticosteroid (ICS)-containing controller treatment (13.9%), other controller treatment (31.59%), anti-asthmatic relivers (23.76%), symptomatic medications (14.54%) and no medication (16.2%). Patients mostly discontinued their controller prescriptions within 6 months after the initial diagnosis. Of the 45.98% patients not receiving any controller medication, 70.16% used relivers or symptomatic medications during follow-up visits. In patients who had 12-month follow-up visits, 76.86%, 17.25%, 5.88% were deemed to have mild, moderate, and severe asthma, respectively, during the 1st 3 months. Percentages of severe and moderate asthma patients were halved by the 2nd 3-month landmark and remained stable over the remaining follow-up visits. There were significant differences in asthma treatment between tertiary and secondary hospitals.Conclusion: In newly diagnosed asthma patients, controller medications were significantly underused while symptom-relief drugs, on the other hand, appeared to be overused. Poor adherence to current guidelines were common and more noticeable in lower tiered hospitals. These findings call for needs of more aggressive asthma management and more educational efforts in China.

BACKGROUND: There are no large sample, epidemiological data describing initial asthma severity and change. We used a large health care database to examine asthma severity at initial diagnosis, and the changes in severity over the first year of management. METHODS: The clinical data of patients diagnosed with asthma for the first time were collated from the SuValue electronic medical database. The following inclusion criteria were applied: (I) patients who were 14 years or older at the time of first diagnosis; (II) initial diagnosis occurred between Jan 2001 and Mar 2019; (III) patients were followed up for at least 12 months; (IV) patients had follow-up visits every 3 months. Disease severity at diagnosis and at each follow-up visit, medications prescribed were collated and analyzed. RESULTS: A total of 7,654 adult patients with newly diagnosed asthma from tertiary hospitals (26.38%) and secondary hospitals (73.62%), who were followed up for at least 12 months, were included in this retrospective analysis. Approximately 54% of patients were females and the largest age group was over 60 years old (37.66%). Nearly 16% of patients were moderate to severe asthma initially. The proportions of patients with moderate and severe asthma decreased during the first 6 months, and remained stable thereafter. At the end of the 1-year follow-up period, 2.7% of patients had severe asthma. Patients with mild asthma tended to continue to have mild asthma in the following 3 months (>76.19%). However, of the patients with mild or moderate asthma at 3 months, 92.85% and 75.1%, respectively, experienced maintenance and reduction in severity and had mild asthma by 12 months. 1.26% and 3.15% of patients with mild or moderate asthma, respectively, progressed to severe asthma by 12 months. CONCLUSIONS: Patients with mild asthma did not progress but rather, remained stable with mild asthma over the year. A proportion of patients diagnosed with moderate and severe asthma remained stable over a 1-year period. Further studies should be conducted to examine the clinical features of newly diagnosed patients with severe asthma without reduction in severity in order to facilitate intensive treatment and reduce the disease burden for these patients.

Recent studies have indicated that Thymic stromal lymphopoietin (TSLP) plays an important role in the prevention and treatment of asthma. However the role of TSLP in dysfunction of airway epithelial adherens junctions E-cadherin in house dust mite (HDM)-induced asthma has not been addressed. We hypothesized that TSLP contributed to HDM-induced E-cadherin dysfunction in asthmatic BALB/c mice and 16HBE cells. In vivo, a HDM-induced asthma mouse model was set up for 8weeks. Mice inhaled an anti-TSLP monoclonal antibody (mAb) before HDM. The mice treated with the anti-TSLP mAb ameliorated airway inflammation, the decreasing and aberrant distribution of E-cadherin and β-catenin as well as phosphorylation(p)-AKT induced by HDM. In vitro, HDM increased the expression of TSLP and E-cadherin dysfunction by PI3K/Akt signaling pathway. The exposure of 16HBE to TSLP resulted in redistribution of E-cadherin. These results indicate that TSLP may be an important contributor in E-cadherin dysfunction of HDM-induced asthma. TSLP signaling blocking shows a protective effect in mice and that the PI3K/Akt pathway may play a role in this process.

Background The disruption and hyperpermeability of bronchial epithelial barrier are closely related to the pathogenesis of asthma. House dust mite (HDM), one of the most important allergens, could increase the airway epithelial permeability. Heat shock protein (Hsp) 90α is also implicated in the lung endothelial barrier dysfunction by disrupting RhoA signaling. However, the effect of extracellular Hsp90α (eHsp90α) on the bronchial epithelial barrier disruption induced by HDM has never been reported. Methods To investigate the involvement of eHsp90α in the bronchial epithelial barrier disruption induced by HDM, normal human bronchial epithelial cell line 16HBE14o- (16HBE) cells were treated by HDM, human recombinant (hr) Hsp90α and hrHsp90β respectively and pretreated by1G6-D7, a specific anti-secreted Hsp90α monoclonal antibody (mAb). Hsp90α-silencing cells were also constructed. To further evaluate the role of RhoA signaling in this process, cells were pretreated by inhibitors of Rho kinase, GSK429286A and Y27632 2HCl. Transepithelial electrical resistance (TEER) and FITC-dextran flux (FITC-DX) were examined as the epithelial barrier function. Expression and localization of adherens junctional proteins E-cadherin and β-catenin were evaluated by western blotting and immunofluorescence respectively. The level of eHsp90α was investigated by concentration and purification of condition media. RhoA activity was determined by using a Rho G-LISA® RhoA activation assay kitTM biochem kit, and the phosphorylation of myosin light chain (MLC), the downstream signal molecule of RhoA, was assessed by western blotting. Results The epithelial barrier disruption and the loss of adherens junctional proteins E-cadherin and β-catenin in cytomembrane were observed in HDM-treated 16HBE cells, paralleled with the increase of eHsp90α secretion. All of which were rescued in Hsp90α-silencing cells or by pretreating 16HBE cells with 1G6-D7. Also, 1G6-D7 suppressed RhoA activity and MLC phosphorylation induced by HDM. Furthermore, inhibitors of Rho kinase prevented and restored the airway barrier disruption. Consistently, it was hrHsp90α instead of hrHsp90β that promoted barrier dysfunction and activated RhoA/MLC signaling in 16HBE cells. Conclusions The eHsp90α mediates HDM-induced human bronchial epithelial barrier dysfunction by activating RhoA/MLC signaling, suggesting that eHsp90α is a potential therapeutic target for treatment of asthma.

Background The dysfunction of airway epithelial barrier is closely related to the pathogenesis of asthma. Secreted Hsp90α participates in inflammation and Hsp90 inhibitor protects endothelial dysfunction. In the current study, we aimed to explore the role of secreted Hsp90α in asthmatic airway epithelial barrier function. Methods Male BALB/c mice were sensitized and challenged with HDM to generate asthma model. The 16HBE and Hsp90α-knockdown cells were cultured and treated according to the experiment requirements. Transepithelial Electric Resistance (TEER) and permeability of epithelial layer in vitro, distribution and expression of junction proteins both in vivo and in vitro were used to evaluate the epithelial barrier function. Western Blot was used to evaluate the expression of junction proteins and phosphorylated AKT in cells and lung tissues while ELISA were used to evaluate the Hsp90α expression and cytokines release in the lung homogenate. Results HDM resulted in a dysfunction of airway epithelial barrier both in vivo and in vitro, paralleled with the increased expression and release of Hsp90α. All of which were rescued in Hsp90α-knockdown cells or co-administration of 1G6-D7. Furthermore, either 1G6-D7 or PI3K inhibitor LY294002 suppressed the significant phosphorylation of AKT, which caused by secreted and recombinant Hsp90α, resulting in the restoration of epithelial barrier function. Conclusions Secreted Hsp90α medicates HDM-induced asthmatic airway epithelial barrier dysfunction via PI3K/AKT pathway, indicating that anti-secreted Hsp90α therapy might be a potential treatment to asthma in future.

There were few knowledge concerned correlation between lung microbiome and different clinicopathology of lung cancer. Bronchial washing fluid (BWF) and sputum are commonly used sample types but there was no study comparing difference of microbiome between these two in lung cancer. In this study, we aimed to compare difference of microbiome between these two sample types and characterize lung microbiome in squamous cell lung carcinoma with (SCC_M1) or without distant metastasis (SCC_M0) and lung adenocarcinoma with (AD_M1) or without distant metastasis (AD_M0). We collected 40 BWF samples and 52 sputum samples from newly diagnosed lung cancer patients. Bacterial species were sequenced via 16S rRNA sequencing. Phylum Proteobacteria in BWF samples were significantly higher than sputum samples (Wilcoxon test, P = 0.003). At phylum level, microbiome of BWF samples was more similar to that of lung cancer tissues reported in the previous literature. LEFse analysis showed that in BWF group, genera Veillonell, Megasphaera, Actinomyces and Arthrobacter in AD_M0 were significantly higher than those in SCC_M0, and genera Capnocytophaga and Rothia in AD_M1 were significantly lower than that in SCC_M1. Compared with AD_M0, genus Streptococcus of AD_M1 was significantly lower, and genera Veillonella and Rothia in SCC_M1 were significantly higher than that in SCC_M1. Our study suggested that BWF samples might better reflect the microbiome of lung cancer tissues. In different metastatic states of lung cancer, differential genera between squamous cell carcinoma and adenocarcinoma were different. And in different histologic types of lung cancer, distant metastasis-related genera were not the same.

BACKGROUND AND PURPOSE Cytoplasmic retention of β-catenin will lead to its nuclear translocation and subsequent interaction with the transcription factor TCF/LEF that regulates target gene expression. We have previously demonstrated aberrant expression of β-catenin in a model of asthma induced by toluene diisocyanate (TDI). The aim of this study was to examine whether the receptor for advanced glycation end products (RAGE) can regulate β-catenin expression in TDI-induced asthma. EXPERIMENTAL APPROACH Male BALB/c mice were sensitized and challenged with TDI to generate a chemically-induced asthma model. Inhibitors of RAGE, FPS-ZM1 and the RAGE antagonist peptide (RAP), were injected i.p. after each challenge. Airway resistance was measured in vivo and bronchoalveolar lavage fluid was analysed. Lungs were examined by histology and immunohistochemistry. Western blotting and quantitative PCR were also used. KEY RESULTS Expression of RAGE and of its ligands HMGB1, S100A12, S100B, HSP70 was increased in TDI-exposed lungs. These increases were inhibited by FPS-ZM1 or RAP. Either antagonist blunted airway reactivity, airway inflammation and goblet cell metaplasia, and decreased release of Th2 cytokines. TDI exposure decreased level of membrane β-catenin, phosphorylated Akt (Ser(473) ), inactivated GSK3β (Ser(9) ), dephosphorylated β-catenin at Ser(33) /(37) /Thr(41) , which controls its cytoplasmic degradation, increased phosphorylated β-catenin at Ser(552) , raised cytoplasmic and nuclear levels of β-catenin and up-regulated its targeted gene expression (MMP2, MMP7, MMP9, VEGF, cyclin D1, fibronectin), all of which were reversed by RAGE inhibition. CONCLUSION AND IMPLICATIONS RAGE was required for stabilization of β-catenin in TDI-induced asthma, identifying protective effects of RAGE blockade in this model.

Recent studies have indicated that high-mobility group box 1 protein (HMGB1) and the receptor for advanced glycation end-products (RAGE) contribute to the pathogenesis of asthma. However, whether the activation of the HMGB1/RAGE axis mediates airway epithelial barrier dysfunction remains unknown. Thus, the aim of this study was to examine the effects of HMGB1 and its synergistic action with interleukin (IL)-1β on airway epithelial barrier properties. We evaluated the effects of recombinant human HMGB1 alone or in combination with IL-1β on ionic and macromolecular barrier permeability, by culturing air-liquid interface 16HBE cells with HMGB1 to mimic the differentiated epithelium. Western blot analysis and immunofluorescence staining were utilized to examine the level and structure of major junction proteins, namely E-cadherin, β-catenin, occludin and claudin-1. Furthermore, we examined the effects of RAGE neutralizing antibodies and mitogen-activated protein kinase (MAPK) inhibitors on epithelial barrier properties in order to elucidate the mechanisms involved. HMGB1 increased FITC-dextran permeability, but suppressed epithelial resistance in a dose- and time-dependent manner. HMGB1-mediated barrier hyperpermeability was accompanied by a disruption of cell-cell contacts, the selective downregulation of occludin and claudin-1, and the redistribution of E-cadherin and β-catenin. HMGB1 in synergy with IL-1β induced a similar, but greater barrier hyperpermeability and induced the disruption of junction proteins. Furthermore, HMGB1 elicited the activation of the RAGE/extracellular signal-related kinase (ERK)1/2 signaling pathway, which correlated with barrier dysfunction in the 16HBE cells. Anti-RAGE antibody and the ERK1/2 inhibitor, U0126, attenuated the HMGB1-mediated changes in barrier permeability, restored the expression levels of occludin and claudin-1 and pevented the redistribution of E-cadherin and β-catenin. Taken together, the findings of our study demonstrate that HMGB1 is capable of inducing potent effects on epithelial barrier function and that RAGE/ERK1/2 is a key signaling pathway involved in the crosstalk between formations of junction proteins and epithelial barrier dysfunction.

Introduction Fractional exhaled nitric oxide (FeNO) has been used as a marker of airway inflammation. Airway caliber is related to the level of FeNO in asthmatics. Objectives This study aimed to investigate whether airway obstruction could interfere with real FENO levels and if different FeNO changes after albuterol inhalation could assist in distinguishing asthma from chronic obstructive pulmonary disease (COPD). Methods FeNO and spirometry measurements were performed before and after albuterol inhalation in the following three patient groups: 30 steroid-naive asthmatics, 25 asthmatics inhaling corticosteroids/long-acting β(2)-adrenergic agonists for at least 1 month and 20 COPD patients. Bronchodilator test (BDT) results were positive in all patients enrolled. The correlations among FeNO levels, pulmonary function and sputum eosinophil counts were analyzed. Results FeNO increased significantly after albuterol inhalation in steroid-naive asthmatics but not in ICS-treated asthmatics or COPD patients. The FeNO levels demonstrated no significant correlation with spirometry results or sputum eosinophil counts before or after inhaling bronchodilator in all three groups. Both the levels of FeNO and changes in FENO after albuterol inhalation in steroid-naive asthma patients were higher than those in ICS-treated asthmatics and COPD patients (P

Cell-cell junctions are critical for the maintenance of cellular as well as tissue polarity and integrity. Yet the role of phosphatidylinositol 3-kinase (PI3K) in dysregulation of airway epithelial adherens junctions in toluene diisocyanate (TDI)-induced asthma has not been addressed. Male BALB/c mice were first dermally sensitized and then challenged with TDI by means of compressed air nebulization. The mice were treated intratracheally with PI3K inhibitor LY294002. Levels of phospho-Akt in airway epithelium and whole lung tissues were markedly increased in TDI group compared with control mice, which decreased after administration of LY294002. The dilated intercellular spaces of airway epithelium induced by TDI were partially recovered by LY294002. Both the protein expression and distribution of adherens junction proteins E-cadherin and β-catenin were altered by TDI. Treatment with LY294002 rescued the distribution of E-cadherin and β-catenin at cell-cell membranes, restored total β-catenin pool, but had no effect on protein level of E-cadherin. At the same time, LY294002 also inhibited phosphorylation of ERK, glycogen synthase kinase3β and tyrosine 654 of β-catenin induced by TDI. In summary, our results showed that the PI3K pathway mediates β-catenin dysregulation in a TDI-induced murine asthma model, which may be associated with increased tyrosine phosphorylation of β-catenin.

Short thymic stromal lymphopoietin (short TSLP), one of TSLP variants, exerts anti-inflammatory activities in endotoxin shock and colitis mouse models. Our latest work reported that short TSLP prevented house dust mite-induced epithelial barrier disruption. Yet the role of short TSLP in toluene diisocyanate (TDI)-induced asthma is unknown. Male BALB/c mice were sensitized and challenged with TDI to generate a chemical-induced asthma model. Synthetic short TSLP peptides were given intranasally or intraperitoneally before each challenge. TDI significantly increased inflammation and hyperresponsiveness of airway, which were suppressed by short TSLP treatment. Levels of mouse TSLP, high mobility group box 1 (HMGB1), and receptor for advanced glycation end products (RAGE) in airway epithelium and whole lung tissues were markedly increased in TDI group compared with control mice, which were decreased after administration of short TSLP. Meanwhile, short TSLP also inhibited STAT5(Y694) phosphorylation, which was highly expressed in airways of TDI-exposure mice. In vitro, both TDI-human serum albumin (HSA) and recombinant human (rh) HMGB1 promoted long TSLP but not short TSLP gene production in human bronchial epithelial cells (16HBE). Cells pre-treated with short TSLP exhibited less expression of RAGE and long TSLP and lower phosphorylation of Akt(S473), p38 MAPK(T180/Y182), and STAT5(Y694) than stimulated with TDI-HSA or rhHMGB1 alone. Results suggest that short TSLP prevents airway inflammation in a chemical-induced asthma model, which might be associated with the inhibitions of HMGB1-RAGE and long TSLP expression and STAT5(Y694) phosphorylation.

Vitamin D exerts profound effects on airway epithelial cells. Thymic stromal lymphopoietin (TSLP) derived from airway epithelial cells plays a role in the innate and antigen‑specific adaptive immune responses. However, the effect of vitamin D on TSLP expression in airway epithelial cells is unclear. In this study, 16-HBE human bronchial epithelial (HBE) cells were cultured with various concentrations of 25-hydroxyvitamin D(3) (25 D(3)) and 1,25-dihydroxyvitamin D(3) (1,25 D(3)). The expression of TSLP in the 16-HBE human bronchial epithelial cell line was analyzed by PCR and enzyme-linked immunosorbent assay (ELISA). We found that the 16-HBE cells converted inactive 25 D(3) to active 1,25 D(3) and that TSLP mRNA and protein expression levels were significantly increased, peaking at 2 or 12 h in the cells exposed to 500 nM 25 D(3) and 50 nM 1,25 D(3) respectively. Since vitamin D(3) upregulated protein 1 (VDUP1) plays a multifunctional role in a variety of cellular responses, we hypothesized that VDUP1 is involved in the induction of TSLP production by 25 D(3). The results showed that the mRNA and protein levels of VDUP1 were significantly upregulated by vitamin D. Furthermore, the silencing of VDUP1 by small interfering RNA (siRNA) significantly inhibited the 25 D(3)- and 1,25 D(3)-mediated induction of TSLP expression. To characterize the metabolic properties of vitamin D in airway epithelial biology, we used the chemical inhibitor of 1α-hydroxylase, itraconazole. The results revealed that itraconazole (10-6 M) reduced the 25 D(3)- but not the 1,25 D(3)-induced TSLP expression in 16-HBE cells. Based on these data, it can be concluded that vitamin D increases TSLP expression in 16-HBE cells through the VDUP1 pathway, which suggests a novel mechanism by which vitamin D alters immune function in the lungs.

Loss of airway epithelial integrity contributes significantly to asthma pathogenesis. Thymic stromal lymphopoietin (TSLP) may have dual immunoregulatory roles. In inflammatory disorders of the bowel, the long isoform of TSLP (lfTSLP) promotes inflammation while the short isoform (sfTSLP) inhibits inflammation. We hypothesize that lfTSLP contributes to house dust mite (HDM)-induced airway epithelial barrier dysfunction and that synthetic sfTSLP can prevent these effects. In vitro, airway epithelial barrier function was assessed by monitoring transepithelial electrical resistance, fluorescent-dextran permeability, and distribution of E-cadherin and β-catenin. In vivo, BALB/c mice were exposed to HDM by nasal inhalation for 5 consecutive days per week to establish an asthma model. sfTSLP and 1α,25-Dihydroxyvitamin D3 (1,25D3) were administered 1 h before HDM exposure. After 8 weeks, animal lung function tests and pathological staining were performed to evaluate asthma progression. We found that HDM and lfTSLP impaired barrier function. Treatment with sfTSLP and 1,25D3 prevented HDM-induced airway epithelial barrier disruption. Moreover, sfTSLP and 1,25D3 treatment ameliorated HDM-induced asthma in mice. Our data emphasize the importance of the different expression patterns and biological properties of sfTSLP and lfTSLP. Moreover, our results indicate that sfTSLP and 1,25D3 may serve as novel therapeutic agents for individualized treatment of asthma.

Pulmonary fibrosis is characterized by lung fibroblast activation and ECM deposition and has a poor prognosis. Heat shock protein 90 (Hsp90) participates in organ fibrosis, and extracellular Hsp90α (eHsp90α) promotes fibroblast activation and migration. This study aimed to investigate whether a selective anti-Hsp90α monoclonal antibody, 1G6-D7, could attenuate lung fibrosis and whether 1G6-D7 presents a protective effect by inactivating the profibrotic pathway. Our results showed that eHsp90α was increased in mice with BLM-induced pulmonary fibrosis and that 1G6-D7 attenuated inflammation and collagen deposition in the lung. TGF-β1 induced eHsp90α secretion, concomitantly promoting HFL-1 activation and ECM synthesis. 1G6-D7-mediated inhibition of eHsp90α significantly blocked these effects, meanwhile inhibiting downstream profibrotic pathways such as ERK, Akt, and P38. Human recombinant (hr)Hsp90α mimicked the effects of TGF-β1, by activating profibrotic pathways and by upregulating LRP-1. Moreover, ERK inhibition effectively blocked the effect of (hr)Hsp90α. In conclusion, 1G6-D7 significantly protects against BLM-induced pulmonary fibrosis by ameliorating fibroblast activation and ECM production, which may be through blocking ERK signaling. Our results suggest a safer molecular therapy, 1G6-D7, in pulmonary fibrosis.

Cytoplasmic retention of β-catenin will lead to its nuclear translocation and subsequent interaction with the transcription factor TCF/LEF that regulates target gene expression. We have previously demonstrated aberrant expression of β-catenin in a model of asthma induced by toluene diisocyanate (TDI). The aim of this study was to examine whether the receptor for advanced glycation end products (RAGE) can regulate β-catenin expression in TDI-induced asthma.Male BALB/c mice were sensitized and challenged with TDI to generate a chemically-induced asthma model. Inhibitors of RAGE, FPS-ZM1 and the RAGE antagonist peptide (RAP), were injected i.p. after each challenge. Airway resistance was measured in vivo and bronchoalveolar lavage fluid was analysed. Lungs were examined by histology and immunohistochemistry. Western blotting and quantitative PCR were also used.Expression of RAGE and of its ligands HMGB1, S100A12, S100B, HSP70 was increased in TDI-exposed lungs. These increases were inhibited by FPS-ZM1 or RAP. Either antagonist blunted airway reactivity, airway inflammation and goblet cell metaplasia, and decreased release of Th2 cytokines. TDI exposure decreased level of membrane β-catenin, phosphorylated Akt (Ser(473) ), inactivated GSK3β (Ser(9) ), dephosphorylated β-catenin at Ser(33) /(37) /Thr(41) , which controls its cytoplasmic degradation, increased phosphorylated β-catenin at Ser(552) , raised cytoplasmic and nuclear levels of β-catenin and up-regulated its targeted gene expression (MMP2, MMP7, MMP9, VEGF, cyclin D1, fibronectin), all of which were reversed by RAGE inhibition.RAGE was required for stabilization of β-catenin in TDI-induced asthma, identifying protective effects of RAGE blockade in this model.

Rapidly growing tumours in vivo often outgrow their surrounding available blood supply, subjecting themselves to a severely hypoxic microenvironment. Understanding how tumour cells adapt themselves to survive hypoxia may help to develop new treatments of the tumours. Given the limited blood perfusion to the enlarging tumour, whatever factor(s) that allows the tumour cells to survive likely comes from the tumour cells themselves or its associated stromal cells. In this report, we show that HIF-1α-overexpressing breast cancer cells, MDA-MB-231, secrete heat shock protein-90alpha (Hsp90α) and use it to survive under hypoxia. Depletion of Hsp90α secretion from the tumour cells was permissive to cytotoxicity by hypoxia, whereas supplementation of Hsp90α-knockout tumour cells with recombinant Hsp90α, but not Hsp90β, protein prevented hypoxia-induced cell death via an autocrine mechanism through the LDL receptor-related protein-1 (LRP1) receptor. Finally, direct inhibition of the secreted Hsp90α with monoclonal antibody, 1G6-D7, enhanced tumour cell death under hypoxia. Therefore, secreted Hsp90α is a novel survival factor for certain tumours under hypoxia.

To explore the polarization of migration dynamics of neutrophils isolated from patients with asthma, chronic obstructive pulmonary disease (COPD) and asthma-COPD overlap syndrome (ACOS) compared with healthy smoking and non-smoking controls.Recruited volunteers were classified as healthy controls, healthy smokers, asthma, COPD and ACOS at Nanfang Hospital from April 2013 to June 2014 according to the Global Strategy for the Diagnosis, Management and Prevention of COPD 2011, Global Strategy for Asthma Management and Prevention 2011 and Consensus on Overlap Phenotype COPD-asthma in COPD 2012. Neutrophils were freshly isolated from whole blood with density gradient technique. The proportion of polarized cells with gradient concentration of formyl-Met-Leu-Phe (fMLP) in Zigmond chamber and vital component of Store Operated Calcium Entry (SOCE) (stromal interaction molecule (STIM) 1, 2 and Orai1) in neutrophils was detected by Western blot.Asthma, COPD and ACOS neutrophils demonstrated a higher spontaneous polarization rate versus healthy controls and healthy smokers ((25.05 ± 4.06)%, (16.20 ± 4.46)%, (29.43 ± 5.53)% vs (7.27 ± 0.99)%, (7.06 ± 3.12)%, all P0.01), asthma and ACOS neutrophils showed a higher directed polarization rate ((14.62 ± 2.26)%, (8.00 ± 1.75)%, all P0.05), but COPD had a relatively lower rate of directional polarization rate than healthy controls and healthy smokers ((2.45 ± 0.54)% vs (5.12 ± 1.28)%, (5.24 ± 1.34)%, all P0.01). The vital component of SOCE in neutrophils from asthma, COPD and ACOS were all up-regulated versus healthy controls and healthy smokers (STIM1: 1.63 ± 0.14, 0.88 ± 0.41, 1.29 ± 0.22 vs 0.26 ± 0.14, 0.38 ± 0.12; STIM2: 0.52 ± 0.19, 0.22 ± 0.13, 0.24 ± 0.10 vs 0.05 ± 0.03, 0.10 ± 0.06; Orai1: 0.56 ± 0.04, 0.39 ± 0.05, 0.48 ± 0.05 vs 0.13 ± 0.04, 0.13 ± 0.03) (all P0.01).Asthma, COPD and ACOS neutrophils are intrinsically different than counterparts from healthy control subjects and healthy smokers. And vital components of SOCE from patient neutrophils are intrinsically up-regulated.

AimsEndothelial dysfunction, including increased endothelial permeability, is considered an early marker for atherosclerosis. High-mobility group box 1 protein (HMGB1) and extracellular Ca2+ entry, primarily mediated through store-operated Ca2+ entry (SOCE), are known to be involved in increasing endothelial permeability. The aim of this study was to clarify how HMGB1 could lead to endothelia hyperpermeability.Methods and resultsWe have shown that human vascular endothelial cell permeability is increased, while transendothelial electrical resistance and VE-cadherin expression were reduced by HMGB1 treatment. Two SOCE inhibitors and knockdown of stromal interaction molecule 1 (STIM1), a Ca2+ sensor mediating SOCE, inhibited the HMGB1-induced influx of Ca2+ and Src activation followed by significant suppression of endothelial permeability. Moreover, knockdown of Orai1, an essential pore-subunit of SOCE channels, decreased HMGB1-induced endothelial hyperpermeability.ConclusionsThese data suggest that SOCE, acting via STIM1, might be the predominant mechanism of Ca2+ entry in the modulation of endothelial cell permeability. STIM1 may thus represent a possible new therapeutic target against atherosclerosis.