DACH1 Attenuates Airway Inflammation in Chronic Obstructive Pulmonary Disease by Activating NRF2 Signaling.

Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory disease of the airways characterized by impaired lung function induced by cigarette smoke (CS). Reduced DACH1 (dachshund homolog 1) expression has a detrimental role in numerous disorders, but its role in COPD remains understudied. This study aimed to elucidate the role and underlying mechanism of DACH1 in airway inflammation in COPD by measuring DACH1 expression in lung tissues of patients with COPD. Airway epithelium-specific DACH1-knockdown mice and adenoassociated virus-transfected DACH1-overexpressing mice were used to investigate the role of DACH1 and the potential for therapeutic targeting in experimental COPD caused by CS. Furthermore, we discovered a potential mechanism of DACH1 in inflammation induced by CS extract stimulation in vitro. Compared with nonsmokers and smokers without COPD, patients with COPD had reduced DACH1 expression, especially in the airway epithelium. Airway epithelium-specific DACH1 knockdown aggravated airway inflammation and lung function decline caused by CS in mice, whereas DACH1 overexpression protected mice from airway inflammation and lung function decline. DACH1 knockdown and overexpression promoted and inhibited IL-6 and IL-8 secretion, respectively, in 16HBE human bronchial epidermal cells after CS extract stimulation. NRF2 (nuclear factor erythroid 2-related factor 2) was discovered to be a novel downstream target of DACH1, which binds directly to its promoter. By activating NRF2 signaling, DACH1 induction reduced inflammation. DACH1 levels are lower in smokers and nonsmoking patients with COPD than in nonsmokers. DACH1 has protective effects against inflammation induced by CS by activating the NRF2 signaling pathway. Targeting DACH1 is a potentially viable therapeutic approach for COPD treatment.

DNA hypomethylation-mediated upregulation of GADD45B facilitates airway inflammation and epithelial cell senescence in COPD.

INTRODUCTION: Chronic obstructive pulmonary disease (COPD) is a heterogeneous disease typically characterized by chronic airway inflammation, with emerging evidence highlighting the driving role of cellular senescence-related lung aging. Accelerated lung aging and inflammation mutually reinforce each other, creating a detrimental cycle that contributes to disease progression. Growth arrest and DNA damage-inducible (GADD45) family has been reported to involve in multiple biological processes, including inflammation and senescence. However, the role of GADD45 family in COPD remains elusive. OBJECTIVES: To investigate the role and mechanism of GADD45 family in COPD pathogenesis. METHODS: Expressions of GADD45 family were evaluated by bioinformatic analysis combined with detections in clinical specimens. The effects of GADD45B on inflammation and senescence were investigated via constructing cell model with siRNA transfection or overexpression lentivirus infection and animal model with Gadd45b knockout. Targeted bisulfite sequencing was performed to probe the influence of DNA methylation in GADD45B expression in COPD. RESULTS: GADD45B expression was significantly increased in COPD patients and strongly associated with lung function, whereas other family members presented no changes. GADD45B upregulation was confirmed in mice exposed by cigarette smoke (CS) and HBE cells treated by CS extract as well. Moreover, experiments involving bidirectional modulation of GADD45B expression in HBE cells further substantiated its positive regulatory role in inflammatory response and cellular senescence. Mechanically, GADD45B-facilitated inflammation was directly mediated by p38 phosphorylation, while GADD45B interacted with FOS to promote cellular senescence in a p38 phosphorylation-independent manner. Furthermore, Gadd45b deficiency remarkably alleviated inflammation and senescence of lungs in CS-exposed mice, as well as improved emphysema and lung function. Eventually, in vivo and vitro experiments demonstrated that GADD45B overexpression was partially mediated by CS-induced DNA hypomethylation. CONCLUSION: Our findings have shed light on the impact of GADD45B in the pathogenesis of COPD, thereby offering a promising target for intervention in clinical settings.

Validation of COPD Population Screener Questionnaire in Chinese Population: A National Multicenter Study.

INTRODUCTION: Chronic obstructive pulmonary disease (COPD) is highly prevalent and underdiagnosed worldwide. The validity and reliability of COPD Population Screening (COPD-PS) questionnaire are not properly known in a large-sample Chinese population. METHODS: This is a national multicenter prospective study that enrolled 1,824 outpatients from 12 hospital sites in China. Scores of the Chinese version of COPD-PS questionnaire, demographic data, and clinical information were collected. The validity and the test-retest reliability were evaluated. RESULTS: 1,824 participants were involved in this study, and 404 (22.1%) were diagnosed with COPD. The overall area under the curve (AUC) of the receiver operating characteristic (ROC) for COPD-PS questionnaire was 0.761 (95% CI: 0.734-0.787). A cut-off point of 4 was recommended, corresponding to a sensitivity of 74.50% and a specificity of 64.37%. The COPD-PS questionnaire showed an overall Pearson's correlation of 0.88. CONCLUSIONS: The COPD-PS questionnaire can be used in screening COPD patients from the general Chinese population with respiratory symptoms.

Genetic Programs Between Steroid-Sensitive and Steroid-Insensitive Interstitial Lung Disease.

The effectiveness of corticosteroids (GCs) varies greatly in interstitial lung diseases (ILDs). In this study, we aimed to compare the gene expression profiles of patients with cryptogenic organizing pneumonia (COP), idiopathic pulmonary fibrosis (IPF), and non-specific interstitial pneumonia (NSIP) and identify the molecules and pathways responsible for GCs sensitivity in ILDs. Three datasets (GSE21411, GSE47460, and GSE32537) were selected. Differentially expressed genes (DEGs) among COP, IPF, NSIP, and healthy control (CTRL) groups were identified. Functional enrichment analysis and protein-protein interaction network analysis were performed to examine the potential functions of DEGs. There were 128 DEGs when COP versus CTRL, 257 DEGs when IPF versus CTRL, 205 DEGs when NSIP versus CTRL, and 270 DEGs when COP versus IPF. The DEGs in different ILDs groups were mainly enriched in the inflammatory response. Further pathway analysis showed that "interleukin (IL)-17 signaling pathway" (hsa04657) and "tumor necrosis factor (TNF) signaling pathway" were associated with different types of ILDs. A total of 10 genes associated with inflammatory response were identified as hub genes and their expression levels in the IPF group were higher than those in the COP group. Finally, we identified two GCs' response-related differently expressed genes (FOSL1 and DDIT4). Our bioinformatics analysis demonstrated that the inflammatory response played a pathogenic role in the progression of ILDs. We also illustrated that the inflammatory reaction was more severe in the IPF group compared to the COP group and identified two GCs' response-related differently expressed genes (FOSL1 and DDIT4) in ILDs.

Dach1 deficiency drives alveolar epithelium apoptosis in pulmonary fibrosis via modulating C-Jun/Bim activity.

Dysregulation of type II alveolar epithelial cells (AECII) plays a vital role in the initiation and development of pulmonary fibrosis (PF). Dachshund homolog 1 (Dach1), frequently expressed in epithelial cells with stem cell potential, controls cell proliferation, apoptosis, and cell cycle in tissue development and disease process. In this study, we demonstrated that the lungs collected from PF patients and mice of Bleomycin (BLM)-treated were characterized by low expression of Dachshund homolog 1 (Dach1), especially in AECII. Dach1 deficiency in the alveolar epithelium exacerbated PF in BLM-treated mice, as evidenced by reduced pulmonary function and increased expression of fibrosis markers. Rather, treatment with lung-specific overexpression of Dach1 alleviated histopathological damage, lung compliance, and fibrosis in BLM-treated mice. Moreover, overexpression of Dach1 could inhibit epithelial apoptosis in vitro. Conversely, primary AECII with Dach1 depletion were more susceptible to apoptosis in vivo. Mechanically, Dach1 combined with C-Jun protooncogene selectively bound to the promoter of B-cell lymphoma 2 interacting mediators of cell death (Bim), by which it repressed Bim expression and alleviated epithelial apoptosis. Taken together, our data support that Dach1 in AECII contributes to the progression of PF and may be a viable target for the prevention and treatment of PF.

Transcriptome analysis of the muscle of fast- and slow-growing phoenix barb (Spinibarbus denticulatus denticulatus).

Growth rate is a commercial trait in aquaculture that is influenced by multiple factors, among which genetic composition plays a fundamental role in the growth rate of species. The phoenix barb (Spinibarbus denticulatus denticulatus) is a widely distributed freshwater fish species in South China. Although S. d. denticulatus is reared in South China, the molecular mechanisms underlying the growth rate of the species remain unclear. Here, the authors performed transcriptome analysis of muscle tissues from fast-growing (FG) and slow-growing (SG) S. d. denticulatus at 90, 150, and 300 days after hatch (DAH) to elucidate its growth mechanism. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that differentially expressed genes (DEGs) between the two groups were enriched in pathways related to muscle growth, glycolysis, and energy and lipid metabolism. Nonetheless, a higher number of DEGs were identified in the FG vs. SG groups at 90 and 300 DAH compared with 150 DAH. DEGs identified at 90 DAH were mainly enriched in the GH/IGF axis, PI3K-Akt signalling pathway, AMPK signalling pathway and lipid metabolism highly expressed in FG individuals. DEGs identified at 300 DAH were mainly enriched in PI3K-Akt signalling pathway, glycolysis/gluconeogenesis, gene translation and lipid metabolism. In addition, some genes were expressed during the early growth stage in FG individuals but expressed during the late stage in SG individuals, indicating considerable variations in the expression profiles of growth-related genes at different developmental stages. Overall, these findings contribute to the understanding of the growth mechanism of S. d. denticulatus, which would be useful for the propagation of fast-growing breeds.

Metabolism-Related Gene TXNRD1 Regulates Inflammation and Oxidative Stress Induced by Cigarette Smoke through the Nrf2/HO-1 Pathway in the Small Airway Epithelium.

Chronic obstructive pulmonary disease (COPD), a small airway disease, is regarded as a metabolic disorder. To further uncover the metabolic profile of COPD patients, it is necessary to identify metabolism-related differential genes in small airway epithelium (SAE) of COPD. Metabolism-related differential genes in SAE between COPD patients and nonsmokers were screened from GSE128708 and GSE20257 datasets. KEGG, GO, and PPI analyses were performed to evaluate the pathway enrichment, term enrichment, and protein interaction of candidate metabolism-related differential genes, respectively. RT-PCR was used to verify the mRNA expression of the top ten differential genes. Western blotting was used to evaluate the protein expression of TXNRD1. TXNRD1 inhibitor auranofin (AUR) was used to assess the impact of TXNRD1 on oxidative stress and inflammation induced by cigarette smoke extraction (CSE). Twenty-four metabolism-related differential genes were selected. ALDH3A1, AKR1C3, CYP1A1, AKC1C1, CPY1B1, and TXNRD1 in the top ten genes were significantly upregulated after CSE simulation for 24 h in human bronchial epithelial (16HBE) cells. Among them, CYP1A1 and TXNRD1 also have a significant upregulation in primary SAE after simulation of CSE for 24 h. The overexpression of protein TXNRD1 has also been detected in 16HBE cells, primary SAE stimulated with CSE, and mouse lung exposed to cigarette smoke (CS). Additionally, inhibition of TXNRD1 with 0.1 µM AUR alleviated the expression of IL-6 and reactive oxygen species (ROS) induced by CSE by activating the Nrf2/HO-1 pathway in 16HBE cells. This study identified twenty-four metabolism-related differential genes associated with COPD. TXNRD1 might participate in the oxidative stress and inflammation induced by CS by regulating the activation of the Nrf2/HO-1 pathway.

Identification and validation of genetic signature associated with aging in chronic obstructive pulmonary disease.

Aging plays an essential role in the development for chronic obstructive pulmonary disease (COPD). The aim of this study was to identify and validate the potential aging-related genes of COPD through bioinformatics analysis and experimental validation. Firstly, we compared the gene expression profiles of aged and young COPD patients using two datasets (GSE76925 and GSE47460) from Gene Expression Omnibus (GEO), and identified 244 aging-related different expressed genes (DEGs), with 132 up-regulated and 112 down-regulated. Then, by analyzing the data for cigarette smoke-induced COPD mouse model (GSE125521), a total of 783 DEGs were identified between aged and young COPD mice, with 402 genes increased and 381 genes decreased. Additionally, functional enrichment analysis revealed that these DEGs were actively involved in COPD-related biological processes and function pathways. Meanwhile, six genes were identified as the core aging-related genes in COPD after combining the human DEGs and mouse DEGs. Eventually, five out of six core genes were validated to be up-regulated in the lung tissues collected from aged COPD patients than young COPD patients, namely NKG7, CKLF, LRP4, GDPD3 and CXCL9. Thereinto, the expressions of NKG7 and CKLF were negatively associated with lung function. These results may expand the understanding for aging in COPD.

Increased Methyl-CpG-Binding Domain Protein 2 Promotes Cigarette Smoke-Induced Pulmonary Hypertension.

Pulmonary hypertension (PH) is a chronic vascular proliferative disorder. While cigarette smoke (CS) plays a vital part in PH related to chronic obstructive pulmonary disease (COPD). Methyl-CpG-Binding Domain Protein 2 (MBD2) has been linked to multiple proliferative diseases. However, the specific mechanisms of MBD2 in CS-induced PH remain to be elucidated. Herein, the differential expression of MBD2 was tested between the controls and the PH patients' pulmonary arteries, CS-exposed rat models' pulmonary arteries, and primary human pulmonary artery smooth muscle cells (HPASMCs) following cigarette smoke extract (CSE) stimulation. As a result, PH patients and CS-induced rats and HPASMCs showed an increase in MBD2 protein expression compared with the controls. Then, MBD2 silencing was used to investigate the function of MBD2 on CSE-induced HPASMCs' proliferation, migration, and cell cycle progression. As a consequence, CSE could induce HPASMCs' increased proliferation and migration, and cell cycle transition, which were suppressed by MBD2 interference. Furthermore, RNA-seq, ChIP-qPCR, and MassARRAY were conducted to find out the downstream mechanisms of MBD2 for CS-induced pulmonary vascular remodeling. Subsequently, RNA-seq revealed MBD2 might affect the transcription of BMP2 gene, which furtherly altered the expression of BMP2 protein. ChIP-qPCR demonstrated MBD2 could bind BMP2's promotor. MassARRAY indicated that MBD2 itself could not directly affect DNA methylation. In sum, our results indicate that increased MBD2 expression promotes CS-induced pulmonary vascular remodeling. The fundamental mechanisms may be that MBD2 can bind BMP2's promoter and downregulate its expression. Thus, MBD2 may promote the occurrence of the CS-induced PH.

Human epididymis protein 4 aggravates airway inflammation and remodeling in chronic obstructive pulmonary disease.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a progressive disease characterized by chronic inflammation and airway remodeling. Human epididymis protein 4 (HE4) plays a critical role in various inflammatory or fibrotic diseases. However, the role of HE4 in COPD remains unidentified. METHODS: HE4 expression was determined in the lung tissues from COPD patients and cigarette smoke (CS)-exposed mice using immunohistochemical staining, qPCR, or western blot. The plasma level of HE4 was detected by ELISA. The regulations of HE4 in the expressions of CS extract (CSE)-induced inflammatory cytokines in human bronchial epithelial cells (HBE) were investigated through knockdown or overexpression of HE4. The role of secretory HE4 (sHE4) in the differentiation and proliferation in human pulmonary fibroblast cells (HPF) was explored via qPCR, western blot, CCK8 assay or 5-ethynyl-2'-deoxyuridine (EdU) staining. The probe of related mechanism in CSE-induced HE4 increase in HBE was conducted by administrating N-acetylcysteine (NAC). RESULTS: HE4 was up-regulated in both the lung tissue and plasma of COPD patients relative to controls, and the plasma HE4 was negatively associated with lung function in COPD patients. The same enhanced HE4 expression was verified in CS-exposed mice and CSE-induced HBE, but CSE failed to increase HE4 expression in HPF. In vitro experiments showed that reducing HE4 expression in HBE alleviated CSE-induced IL-6 release while overexpressing HE4 facilitated IL-6 expression, mechanistically through affecting phosphorylation of NFκB-p65, whereas intervening HE4 expression had no distinctive influence on IL-8 secretion. Furthermore, we confirmed that sHE4 promoted fibroblast-myofibroblast transition, as indicated by promoting the expression of fibronectin, collagen I and α-SMA via phosphorylation of Smad2. EdU staining and CCK-8 assay demonstrated the pro-proliferative role of sHE4 in HPF, which was further confirmed by enhanced expression of survivin and PCNA. Pretreatment of NAC in CSE or H2O2-induced HBE mitigated HE4 expression. CONCLUSIONS: Our study indicates that HE4 may participate in airway inflammation and remodeling of COPD. Cigarette smoke enhances HE4 expression and secretion in bronchial epithelium mediated by oxidative stress. Increased HE4 promotes IL-6 release in HBE via phosphorylation of NFκB-p65, and sHE4 promotes fibroblastic differentiation and proliferation.

MTMR14 Alleviates Chronic Obstructive Pulmonary Disease as a Regulator in Inflammation and Emphysema.

Extensive inflammation and apoptosis in structural cells of the lung are responsible for the progression and pathogenesis of chronic obstructive pulmonary disease (COPD). Myotubularin-related protein 14 (MTMR14) has been shown to participate in various biological processes, including apoptosis, inflammation, and autophagy. Nonetheless, the role of MTMR14 in COPD remains elusive. In the present study, we explored the expression of MTMR14 in human lung tissues and investigated the effects of overexpressed MTMR14 on in vitro and in vivo COPD models. Moreover, one of the possible mechanisms of MTMR14 alleviating COPD was explored based on mitochondrial function and mitophagy homeostasis. The results showed that MTMR14 expression was reduced in COPD patients' lungs in comparison to control subjects. MTMR14 overexpression inhibited cigarette smoke extract-induced inflammation and apoptosis and improved mitochondrial function and mitophagy in vitro. Further verification was carried out in COPD model mice. MTMR14 overexpression inhibited lung inflammation and reduced levels of IL-6 and KC in bronchoalveolar lavage fluid, as well as prevented emphysema and a decline in lung function. Furthermore, MTMR14 overexpression improved mitochondrial function and mitophagy to a certain extent. Collectively, our data support the hypothesis that MTMR14 participates in the pathogenesis of COPD. Improving mitochondrial function and mitophagy homeostasis may be one of the mechanisms by which MTMR14 alleviates COPD and may potentially be a novel therapeutic target for COPD.

Cigarette Smoke Promotes Interleukin-8 Production in Alveolar Macrophages Through the Reactive Oxygen Species/Stromal Interaction Molecule 1/Ca2+ Axis.

Chronic obstructive pulmonary disease (COPD), primarily attributed to cigarette smoke (CS), is characterized by multiple pathophysiological changes, including oxidative stress and inflammation. Stromal interaction molecule 1 (STIM1) is a Ca2+ sensor that regulates Ca2+ entry in different types of cells. The present study aimed to explore the relationship between CS-induced oxidative stress and inflammation, as well as the functional role of STIM1 thereinto. Our results showed that the reactive oxygen species (ROS)/STIM1/Ca2+ axis played a critical role in CS-induced secretion of interleukin (IL)-8 in human alveolar macrophages. Specifically, smokers with COPD (SC) showed higher levels of ROS in the lung tissues compared with healthy non-smokers (HN). STIM1 was upregulated in the lung tissues of COPD patients. The expression of STIM1 was positively associated with ROS levels and negatively correlated with pulmonary function. The expression of STIM1 was also increased in the bronchoalveolar lavage fluid (BALF) macrophages of COPD patients and PMA-differentiated THP-1 macrophages stimulated by cigarette smoke extract (CSE). Additionally, CSE-induced upregulation of STIM1 in PMA-differentiated THP-1 macrophages was inhibited by pretreatment with N-acetylcysteine (NAC), a ROS scavenger. Transfection with small interfering RNA (siRNA) targeting STIM1 and pretreatment with NAC alleviated CSE-induced increase in intracellular Ca2+ levels and IL-8 expression. Furthermore, pretreatment with SKF-96365 and 2-APB, the inhibitors of Ca2+ influx, suppressed CSE-induced secretion of IL-8. In conclusion, our study demonstrates that CSE-induced ROS production may increase the expression of STIM1 in macrophages, which further promotes the release of IL-8 by regulating Ca2+ entry. These data suggest that STIM1 may play a crucial role in CSE-induced ROS production and inflammation, and participate in the pathogenesis of COPD.

p55PIK deficiency and its NH2-terminal derivative inhibit inflammation and emphysema in COPD mouse model.

Chronic obstructive pulmonary disease (COPD) is composed of chronic airway inflammation and emphysema. Recent studies show that Class IA phosphatidylinositol 3-kinases (PI3Ks) play an important role in the regulation of inflammation and emphysema. However, there are few studies on their regulatory subunits. p55PIK is a regulatory subunit of Class IA PI3Ks, and its unique NH2-terminal gives it special functions. p55PIK expression in the lungs of nonsmokers, smokers, and patients with COPD was examined. We established a fusion protein TAT-N15 from the NH2-terminal effector sequence of p55PIK and TAT (the transduction domain of HIV transactivator protein) and investigated the effects of silencing p55PIK or adding TAT-N15 on cigarette smoke exposure at the cellular and animal level. p55PIK expression was increased in patients with COPD. p55PIK deficiency and TAT-N15 significantly inhibited the cigarette smoke extract-induced IL-6, IL-8, and activation of the Akt and the NF-κB pathway in BEAS-2B. p55PIK deficiency and TAT-N15 intranasal administration prevented emphysema and the lung function decline in mice exposed to smoke for 6 mo. p55PIK deficiency and TAT-N15 significantly inhibited lung inflammatory infiltration, reduced levels of IL-6 and KC in mice lung homogenate, and inhibited activation of the Akt and the NF-κB signaling in COPD mice lungs. Our studies indicate that p55PIK is involved in the pathogenesis of COPD, and its NH2-terminal derivative TAT-N15 could be an effective drug in the treatment of COPD by inhibiting the activation of the Akt and the NF-κB pathway.

Distinct effects of asthma and COPD comorbidity on disease expression and outcome in patients with COVID-19.

BACKGROUND: The impacts of chronic airway diseases on coronavirus disease 2019 (COVID-19) are far from understood. OBJECTIVE: To explore the influence of asthma and chronic obstructive pulmonary disease (COPD) comorbidity on disease expression and outcomes, and the potential underlying mechanisms in COVID-19 patients. METHODS: A total of 961 hospitalized COVID-19 patients with a definite clinical outcome (death or discharge) were retrospectively enrolled. Demographic and clinical information were extracted from the medical records. Lung tissue sections from patients suffering from lung cancer were used for immunohistochemistry study of angiotensin-converting enzyme II (ACE2) expression. BEAS-2B cell line was stimulated with various cytokines. RESULTS: In this cohort, 21 subjects (2.2%) had COPD and 22 (2.3%) had asthma. After adjusting for confounding factors, COPD patients had higher risk of developing severe illness (OR: 23.433; 95% CI 1.525-360.135; P < .01) and acute respiratory distress syndrome (OR: 19.762; 95% CI 1.461-267.369; P = .025) than asthmatics. COPD patients, particularly those with severe COVID-19, had lower counts of CD4+ T and CD8+ T cells and B cells and higher levels of TNF-α, IL-2 receptor, IL-10, IL-8, and IL-6 than asthmatics. COPD patients had increased, whereas asthmatics had decreased ACE2 protein expression in lower airways, compared with that in control subjects without asthma and COPD. IL-4 and IL-13 downregulated, but TNF-α, IL-12, and IL-17A upregulated ACE2 expression in BEAS-2B cells. CONCLUSION: Patients with asthma and COPD likely have different risk of severe COVID-19, which may be associated with different ACE2 expression.

Circular RNA hsa_circ_0000326 acts as a miR-338-3p sponge to facilitate lung adenocarcinoma progression.

BACKGROUND: Circular RNAs (circRNAs) are a novel class of noncoding RNAs that regulate gene expression at the transcriptional or posttranscriptional level. According to recent studies, circRNAs are involved in the pathogenesis of cancer, but the roles of circRNAs in lung adenocarcinoma are largely unknown. METHODS: In this study, we identified a novel upregulated circRNA, hsa_circ_0000326, in human lung adenocarcinoma tissues using microarray analysis and qRT-PCR. We then explored the biological role of hsa_circ_0000326 using gain- and loss-of-function assays in adenocarcinoma cells. Bioinformatics databases were used to screen for potential target miRNAs and the luciferase reporter assays and RNA-FISH further validated the interaction. Downstream protein was detected by western blot. Finally, we established xenografts in nude mice to assess the function of hsa_circ_0000326 in vivo. RESULTS: We found that high expression of hsa_circ_0000326 was correlated with tumor size, regional lymph node status and differentiation in human lung adenocarcinoma. Additionally, we conducted gain- and loss-of-function assays and found that hsa_circ_0000326 acted as a positive regulator of cell proliferation and migration and a negative regulator of apoptosis. Mechanistic studies showed that hsa_circ_0000326 acted as a miR-338-3p sponge and altered the function of miR-338-3p, which in turn upregulated the expression of the downstream target RAB14 and affected the proliferation, migration and apoptosis of lung adenocarcinoma cells. CONCLUSIONS: Collectively, our study results reveal crucial roles for hsa_circ_0000326 in the proliferation, migration and apoptosis of lung adenocarcinoma cells and suggest that hsa_circ_0000326 may represent a potential therapeutic target in patients with lung adenocarcinoma.

5-HT7 Receptor Contributes to Proliferation, Migration and Invasion in NSCLC Cells.

INTRODUCTION: Because only a small portion of NSCLC (non-small-cell lung cancer) patients benefit from molecular targeted therapy or immunotherapy and do not develop therapeutic resistance, continued research on new targets is warranted. Serotonin has recently emerged as a growth factor for tumor cells, and its receptors may be potential therapeutic targets. The mechanism related to the behavior of the 5-HT7 receptor in NSCLC remains unknown. METHODS: Both gene expression analysis and immunohistochemical analysis were conducted to evaluate 5-HT7 receptor expression in NSCLC tissues. The correlation between 5-HT7 receptor expression and clinicopathological features was also examined. Cell proliferation was measured using a CCK8 (Cell Counting Kit-8) assay and colony formation, migration and invasion were evaluated by the Transwell assay. siRNA transfection and stimulation with the selective agonist LP211 were used to identify the involvement of molecules in proliferation, migration and invasion. Quantitative real-time chain reaction (qRT-PCR) and Western blotting were used to quantifiy mRNA and protein levels, respectively. Pathway inhibitors facilitated the exploration of possible signaling pathways regulated by the 5-HT7 receptor in migration and invasion. RESULTS: The 5-HT7 receptor was overexpressed in NSCLC tumor tissues compared with adjacent normal lung tissues. High 5-HT7 receptor expression levels were correlated with lymph node metastasis (P=0.007) and advanced TNM stage (P=0.000) in NSCLC patients. The 5-HT7 receptor positively regulated cell proliferation, migration and invasion in NSCLC cells. The stimulatory effect of the 5-HT7 receptor on A549 cell migration and invasion may occur through the P38 pathway. In H1299 cells, the 5-HT7 receptor might positively regulate Src to promote cell migration and invasion. CONCLUSION: Our findings suggest that the 5-HT7 receptor, which mediates NSCLC progression, may be a potential therapeutic target.

The effects of BAFF on T lymphocytes in chronic obstructive pulmonary disease.

BACKGROUND: It has been reported that B cell activating factor belonging to the tumor necrosis factor family (BAFF) expression is increased in chronic obstructive pulmonary disease (COPD). However its role in this chronic inflammatory disease is not fully understood. Previous studies have suggested that BAFF also affects T cell function. We therefore investigated the effects of BAFF on T lymphocytes in COPD. METHODS: BAFF was detected in the cells of sputum and the plasma. Peripheral blood mononuclear cells (PBMCs) were isolated from COPD patients and treated with BAFF or BAFF plus BR3-Fc (BAFF antagonist). The apoptosis of CD4+ cells and CD8+ cells was analyzed by flow cytometry. CD4+ cells and CD8+ cells were isolated from peripheral blood of COPD patients respectively and treated with BAFF or BAFF plus BR3-Fc. Interferon-γ (IFN-γ) and interleukin-4 (IL-4) were detected in the CD4+ cells, and perforin and granzyme B were detected in the CD8+ cells. RESULTS: BAFF expression was increased in the cells of sputum and the plasma from COPD patients compared with control subjects. The plasma BAFF levels were inversely correlated with FEV1 percentage of predicted in patients with COPD. BAFF did not significantly alter the apoptosis of CD4+ cells, however it significantly inhibited the apoptosis of CD8+ cells from COPD patients. BAFF increased IFN-γ expression in the CD4+ cells from COPD patients, while it did not significantly alter the expresson of IL-4 in these cells. BAFF increased the expression of perforin and granzyme B in the CD8+ cells from COPD patients. CONCLUSIONS: Our findings indicate that BAFF may be involved in the inflammatory response in COPD via affecting T lymphocytes, suggesting a possible role of BAFF in the pathogenesis of COPD.

Prospective development of practical screening strategies for diagnosis of asthma-COPD overlap.

BACKGROUND AND OBJECTIVE: ACO is a syndrome with high prevalence. However, a pragmatic diagnostic criterion to differentiate ACO is non-existent. We aimed to establish an effective model for screening ACO. METHODS: A multicentre survey was developed to assess the clinical criteria considered important and applicable by pulmonologists for screening ACO. These experts were asked to take the surveys twice. The expert grading method, analytic hierarchy process and ROC curve were used to establish the model, which was then validated by a cross-sectional study of 1066 patients. The GINA/GOLD document was the gold standard in assessing this model. RESULTS: Increased variability of symptoms, paroxysmal wheezing, dyspnoea, historical diagnosis of COPD or asthma, allergic constitution, exposure to risk factors, the FEV1 /FVC < 70% and a positive BDT were important for screening ACO. According to the weight of each criterion, we confirmed that patients meeting six or more of these eight criteria should be considered to have ACO. We called this Chinese screening model for ACO 'CSMA'. It differentiated patients with ACO with a sensitivity of 83.33%, while the sensitivity of clinician-driven diagnosis had a sensitivity of only 42.73%. CONCLUSION: CSMA is a workable model for screening ACO and provides a simple tool for clinicians to efficiently diagnose ACO.

Hsa_circ_0005519 increases IL-13/IL-6 by regulating hsa-let-7a-5p in CD4+ T cells to affect asthma.

BACKGROUND: Circular RNAs (circRNAs) are a class of non-coding RNAs that could serve as novel biomarkers for the diagnosis and treatment of diseases. We hypothesized that circRNAs of CD4+ T cells are involved in asthma. OBJECTIVE: In this study, we investigated the circRNA expression profile and the possible mechanism by which hsa_circ_0005519 participates in asthma. METHODS: The expression profiles of circRNAs in CD4+ T cells were revealed by circRNA microarray. Hsa_circ_0005519 expression in CD4+ T cells was confirmed in asthmatic patients (n = 65) and healthy subjects (n = 30). Hsa-let-7a-5p, the target of hsa_circ_0005519, was predicted by online algorithms and verified by a dual-luciferase reporter assay. Correlation assays between the expression of hsa_circ_0005519 and hsa-let-7a-5p, the mRNA levels of interleukin (IL)-13 and IL-6 in CD4+ T cells, and the clinical characteristics of asthmatic patients were performed. The role of hsa_circ_0005519 in proinflammatory cytokine expression was investigated in CD4+ T cells from asthmatic patients in vitro. Hsa_circ_0005519 expression in PBMCs was determined in another cohort including 30 asthmatic patients and 24 controls. Correlation assays of hsa_circ_0005519 expressions between CD4+ T cells and PBMCs were performed. RESULTS: Hsa_circ_0005519 was up-regulated and negatively correlated with hsa-let-7a-5p expression in CD4+ T cells of asthmatic patients. Both the fraction of exhaled nitric oxide (FeNO) and the peripheral blood eosinophil ratio were positively correlated with hsa_circ_0005519 expression in CD4+ T cells. These outcomes were also different in asthmatic patients with low vs high hsa_circ_0005519 levels. Hsa_circ_0005519 expressions between CD4+ T cells and PBMCs were concordant in asthmatic patients. Mechanistically, hsa_circ_0005519 might bind to hsa-let-7a-5p and relieve suppression for IL-13/IL-6 in CD4+ T cells. CONCLUSIONS AND CLINICAL RELEVANCE: Our data suggest that hsa_circ_0005519 may induce IL-13 and IL-6 expression by regulating hsa-let-7a-5p in CD4+ T cells to affect asthma. And hsa_circ_0005519 may be a potential biomarker of asthma.

Role of PM2.5 in the development and progression of COPD and its mechanisms.

BACKGROUND: A multitude of epidemiological studies have shown that ambient fine particulate matter 2.5 (diameter < 2.5um; PM2.5) was associated with increased morbidity and mortality of chronic obstructive pulmonary disease (COPD). However, the underlying associated mechanisms have not yet been elucidated. We conducted this study to investigate the role of PM2.5 in the development of COPD and associated mechanisms. METHODS: We firstly conducted a cross-sectional study in Chinese han population to observe PM2.5 effects on COPD morbidity. Then, in vitro, we incubated human bronchial epithelial cells to different concentrations of PM2.5 for 24 h. The expression levels of IL-6 and IL-8 were detected by ELISA and the levels of MMPs, TGF-ß1, fibronectin and collagen was determined by immunoblotting. In vivo, we subjected C57BL/6 mice to chronic prolonged exposure to PM2.5 for 48 weeks to study the influence of PM2.5 exposure on lung function, pulmonary structure and inflammation. RESULTS: We found that the effect of PM2.5 on COPD morbidity was associated with its levels and that PM2.5 and cigarette smoke could have a synergistic impact on COPD development and progression. Both vitro and vivo studies demonstrated that PM2.5 exposure could induce pulmonary inflammation, decrease lung function, and cause emphysematous changes. Furthermore, PM2.5 could markedly aggravated cigarette smoke-induced changes. CONCLUSIONS: In short, we found that prolonged chronic exposure to PM2.5 resulted in decreased lung function, emphysematous lesions and airway inflammation. Most importantly, long-term PM2.5 exposure exacerbateed cigarette smoke-induced changes in COPD.