Biomass-related PM2.5 induced inflammatory microenvironment via IL-17F/IL-17RC axis.

Biomass exposure is a significant environmental risk factor for COPD, but the underlying mechanisms have not yet been fully elucidated. Inflammatory microenvironment has been shown to drive the development of many chronic diseases. Pollution exposure can cause increased levels of inflammatory factors in the lungs, leading to an inflammatory microenvironment which is prevalent in COPD. Our findings revealed that IL-17F was elevated in COPD, while exposure to biomass led to increased expression of IL-17F in both alveolar epithelial and macrophage cells in mice. Blocking IL-17F could alleviate the lung inflammation induced by seven days of biomass exposure in mice. We employed a transwell co-culture system to simulate the microenvironment and investigate the interactions between MLE-12 and MH-S cells. We demonstrated that anti-IL-17F antibody attenuated the inflammatory responses induced by BRPM2.5 in MLE-12 and MH-S co-cultured with BRPM2.5-MLE-12, which reduced inflammatory changes in microenvironment. We found that IL-17RC, an important receptor for IL-17F, played a key role in the interactions. Knockout of IL-17RC in MH-S resulted in inhibited IL-17F signaling and attenuated inflammatory response after MH-S co-culture with BRPM2.5-MLE-12. Our investigation suggests that BRPM2.5 induces lung epithelial-macrophage interactions via IL-17F/IL-17RC axis regulating the inflammatory response. These results may provide a novel strategy for effective prevention and treatment of biomass-related COPD.

Prediction of progressive pulmonary fibrosis in patients with anti-synthetase syndrome-associated interstitial lung disease.

OBJECTIVE: Interstitial lung disease (ILD) is a common extramuscular manifestation of the anti-synthetase syndrome (ASS). Patients with ASS-ILD are at risk in developing a progressive fibrosing phenotype despite appropriate treatments. This study investigated the risk factors and the predictive value of multiple risk factors for progressive pulmonary fibrosis (PPF) in patients with ASS-ILD. METHODS: Ninety patients with a diagnosis of ASS and evidence of ILD on high-resolution computed tomography (HRCT) were recruited. Among them, 72 participants completed follow-up for more than 12 months. These patients were further divided into a PPF-ASS group (n = 18) and a non-PPF-ASS group (n = 54). Logistic regression analysis was performed to investigate the risk factors for PPF. The predictive value of the combined risk factors for predicting PPF were analyzed by a ROC curve. RESULTS: The PPF-ASS group had a higher rate of positive non-Jo-1 antibodies, a significantly higher neutrophil-to-lymphocyte ratio (NLR) and serum lactate dehydrogenase (LDH), and a significantly lower PaO2/FiO2 ratio and diffusing capacity for carbon monoxide (DLCO%pred) than the non-PPF-ASS group. In addition, elevated serum Krebs von den Lungen-6 (KL-6) level and reticular opacities were significantly more common, and corticosteroid monotherapy at onset was administered more frequently in the PPF-ASS group. The median duration of follow-up was 37.4 months, survival was poorer in the PPF-ASS group, and the overall survival was 88.9%. Multivariate regression analysis further revealed that positive non-Jo-1 antibodies, NLR, and KL-6 were independent risk factors for PPF. These combined indexes had good accuracy (area under the curve = 0.874) in predicting PPF in patients with ASS-ILD. CONCLUSION: Positive non-Jo-1 antibodies, NLR, and serum KL-6 are independent risk factors for PPF in patients with ASS-ILD. Monitoring these markers can potentially predict PPF in this group of patients. Key Points • Positive non-Jo-1 antibodies, NLR, and serum KL-6 are independent risk factors associated with PPF in patients with ASS-ILD. • Monitoring non-Jo-1 antibodies, NLR, and serum KL-6 can potentially predict PPF in patients with ASS-ILD.

Adenoviral Transduction of Dickkopf-1 Alleviates Silica-Induced Silicosis Development in Lungs of Mice.

Silicosis is an occupational disease caused by inhalation of silica dust, which is hallmarked by progressive pulmonary fibrosis associated with poor prognosis. Wnt/ß-catenin signaling is implicated in the development of fibrosis and is a therapeutic target for fibrotic diseases. Previous clinical studies of patients with pneumoconiosis, including silicosis, revealed an increased concentration of circulating WNT3A and DKK1 proteins and inflammatory cells in bronchoalveolar lavage compared with healthy subjects. The present study evaluated the effects of adenovirus-mediated transduction of Dickkopf-1 (Dkk1), a Wnt/ß-catenin signaling inhibitor, on the development of pulmonary silicosis in mice. Consistent with previous human clinical studies, our experimental studies in mice demonstrated an aberrant Wnt/ß-catenin signaling activity coinciding with increased Wnt3a and Dkk1 proteins and inflammation in lungs of silica-induced silicosis mice compared with controls. Intratracheal delivery of adenovirus expressing murine Dkk1 (AdDkk1) inhibited Wnt/ß-catenin activity in mouse lungs. The adenovirus-mediated Dkk1 gene transduction demonstrated the potential to prevent silicosis development and ameliorate silica-induced lung fibrogenesis in mice, accompanied by the reduced expression of epithelia--mesenchymal transition markers and deposition of extracellular matrix proteins compared with mice treated with "null" adenoviral vector. Mechanistically, AdDkk1 is able to attenuate the lung silicosis by inhibiting a silica-induced spike in TGF-ß/Smad signaling. In addition, the forced expression of Dkk1 suppressed silica-induced epithelial cell proliferation in polarized human bronchial epithelial cells. This study provides insight into the underlying role of Wnt/ß-catenin signaling in promoting the pathogenesis of silicosis and is proof-of-concept that targeting Wnt/ß-catenin signaling by Dkk1 gene transduction may be an alternative approach in the prevention and treatment of silicosis lung disease.

ESRP1 as a prognostic factor of non-small-cell lung cancer is related to the EMT transcription factor of Twist.

OBJECTIVE: Non-small-cell lung cancer (NSCLC) is one of the most common fatal cancers in the world. Although the treatment of NSCLC has been significantly improved, there is still an unmet need to identify novel targets for developing therapeutic agents and diagnostic/prognostic markers. The aim of this study is explore the role and underlying mechanism of the epithelial splicing regulatory protein (ESRP1) in the development and progression of NSCLC. METHODS: A total of 115 participants, 65 cases of NSCLC, 20 cases of precancerous lesions, and 30 cases of benign lung nodules, were included in this study. The expressions of ESRP1 and related transcription factor Twist in enrolled lung tissues were evaluated by histochemistry and immunohistochemistry assay. The survival analysis and related prognosis factors were evaluated by the Kaplan-Meier curve and Cox regression. In addition, the expression of ESRP1 and epithelial-mesenchymal transition (EMT)related transcription factor Twist and EMT markers E-cadherin and N-cadherin were ascertained by immunohistochemical and immunoblotting assay on A549 lung adenocarcinoma cell lines that were exposed to transforming growth factor ß1 (TGFß1). RESULTS: Compared with normal lung tissues, the abundance of ESRP1 protein was significantly increased in precancerous lesions and lung cancer. Correlation analysis demonstrated that ESRP1 was an independent prognostic factor in NSCLC. The expression of ESRP1 and Twist was positively correlated in lung tissues (r = 0.285, p < 0.001). In vitro analysis further showed that TGFß1 could upregulate the expression of EMT transcription factor Twist while downregulating ESRP1. CONCLUSIONS: Our data suggest that the aberrant expression of ESRP1 is an early event in the development of NSCLC. The ESRP1 could serve as a prognostic biomarker for NSCLC, particularly when combined with Twist. The Twist negatively regulated the expression of ESRP1, emphasizing the role of the TGFß/ESRP1 pathway in the development of NSCLC, which warrants further investigation.

NOX4-Derived ROS Promotes Collagen I Deposition in Bronchial Smooth Muscle Cells by Activating Noncanonical p38MAPK/Akt-Mediated TGF-ß Signaling.

BACKGROUND: Airway smooth muscle (ASM) remodeling is a hallmark in chronic obstructive pulmonary disease (COPD). NADPH oxidase 4- (NOX4-) mediated reactive oxygen species (ROS) production plays a crucial role in cell differentiation and extracellular matrix (ECM) synthesis in ASM remodeling. However, the precise mechanisms underpinning its pathogenic roles remain elusive. METHODS: The expression of NOX4 and TGF-ß 1 in the airway of the lung was measured in COPD patients and the control group. Cigarette smoke- (CS-) induced emphysema mice were generated, and the alteration of α-SMA, NOX4, TGF-ß 1, and collagen I was accessed. The changes of the expression of ECM markers, NOX4, components of TGF-ß/Smad, and MAPK/Akt signaling in human bronchial smooth muscle cells (HBSMCs) were ascertained for delineating mechanisms of NOX4-mediated ROS production on cell differentiation and remodeling in human ASM cells. RESULTS: An increased abundance of NOX4 and TGF-ß 1 proteins in the epithelial cells and ASM of lung was observed in COPD patients compared with the control group. Additionally, an increased abundance expression of NOX4 and α-SMA was observed in the lungs of the CS-induced emphysema mouse model. TGF-ß 1 displayed abilities to increase the oxidative burden and collagen I production, along with enhanced phosphorylation of ERK, p38MAPK, and p-Akt473 in HBSMCs. These effects of TGF-ß 1 could be inhibited by the ROS scavenger N-acetylcysteine (NAC), siRNA-mediated knockdown of Smad3 and NOX4, and pharmacological inhibitors SB203580 (p38MAPK inhibitor) and LY294002 (Akt inhibitor). CONCLUSIONS: NOX4-mediated ROS production alters TGF-ß 1-induced cell differentiation and collagen I protein synthesis in HBSMCs in part through the p38MAPK/Akt signaling pathway in a Smad-dependent manner.

NOX4 expression and distal arteriolar remodeling correlate with pulmonary hypertension in COPD.

BACKGROUND: Pulmonary hypertension (PH) in chronic obstructive pulmonary disease (COPD) is suggested as the consequence of emphysematous destruction of vascular bed and hypoxia of pulmonary microenvironment, mechanisms underpinning its pathogenesis however remain elusive. The dysregulated expression of nicotinamide adenine dinucleotide phosphate (NADPH)-oxidases and superoxide generation by pulmonary vasculatures have significant implications in the hypoxia-induced PH. METHODS: In this study, the involvement of NADPH oxidase subunit 4 (NOX4) in pulmonary arteriolar remodeling of PH in COPD was investigated by ascertaining the morphological alteration of pulmonary arteries and pulmonary blood flow using cardiac magnetic resonance imaging (cMRI), and the expression and correlation of NOX4 with pulmonary vascular remodeling and pulmonary functions in COPD lungs. RESULTS: Results demonstrated that an augmented expression of NOX4 was correlated with the increased volume of pulmonary vascular wall in COPD lung. While the volume of distal pulmonary arteries was inversely correlated with pulmonary functions, despite it was positively associated with the main pulmonary artery distensibility, right ventricular myocardial mass end-systolic and right ventricular myocardial mass end-diastolic in COPD. In addition, an increased malondialdehyde and a decreased superoxide dismutase were observed in sera of COPD patients. Mechanistically, the abundance of NOX4 and production of reactive oxygen species (ROS) in pulmonary artery smooth muscle cells could be dynamically induced by transforming growth factor-beta (TGF-ß), which in turn led pulmonary arteriolar remodeling in COPD lungs. CONCLUSION: These results suggest that the NOX4-derived ROS production may play a key role in the development of PH in COPD by promoting distal pulmonary vascular remodeling.

Increased expression of miR-641 contributes to erlotinib resistance in non-small-cell lung cancer cells by targeting NF1.

Epidermal growth receptor (EGFR)-targeted tyrosine kinase inhibitors (TKIs) have emerged as first-line drugs for advanced non-small-cell lung cancer (NSCLC) patients with EFGR mutations. However, most patients with NSCLC show acquired resistance to EGFR-TKIs, and low expression of NF1 is a mechanism of EGFR-TKI resistance in lung cancer. However, the mechanism by which NF1 is downregulated in EGFR-TKI-resistant NSCLC is unclear. Here, we found the increased expression of miR-641 in NSCLC cells and human NSCLC samples with resistance to TKI compared to those with sensitive to TKI. In addition, our in vitro experiments show that overexpression of miR-641 induces TKI resistance in NSCLC cells. Furthermore, we identified that miR-641 activates ERK signaling by direct targeting of neurofibromatosis 1 (NF1) in NSCLC cells. Our data show that overexpression of NF1 or silencing of ERK can block miR-641-induced resistance of NSCLC cells to erlotinib treatment. Importantly, our animal experiments show that combination of miR-641 inhibition and erlotinib treatment can significantly inhibit erlotinib-resistant NSCLC growth, inhibit proliferation and induce apoptosis compared to single-drug treatment. Our findings suggest that increased expression of miR-641 significantly contributes to erlotinib resistance development in NSCLC cells through activating ERK signaling by targeting NF1 and that inhibition of miR-641 may reverse acquired resistance of NSCLC cells to erlotinib treatment.

[The effects of NOX4 and TGF-ßinvolved in airway remodeling of Chronic Obstructive Pulmonary Disease].

OBJECTIVE: To investigate the role of nicotinamide adenine dinucleotide phosphate 4 (NADPH4,NOX4) and transforming growth factor-beta (TGF-ß) involve in pathogenesis of airway remodeling in chronic obstructive pulmonary disease (COPD). METHODS: Lung tissues from 36 COPD patients and 19 patients with normal lung function were enrolled in this study. The volume of airway smooth muscle (ASM)mass was evaluated. The expressions of NOX4, collagen Ⅳ (Col Ⅳ) and TGF-ß were tested by a semi-quantitative morphological and/or immunohistochemistry staining method and Western blot, and their correlations with pulmonary functions were analyzed. RESULTS: ①Index of the percentage of the thickness of ASM/external diameter of small airway (WT%) and the percentage of the area of ASM/transverse area of small airway (WA%) were significantly higher in the COPD group than those in controls(P<0.05).②In COPD patients,epithelial cells metaplasia were found and α-SMA and Col Ⅳwere expressed in a part of epithelial cells. The expressions of α-small muscle actin (α-SMA) and Col Ⅰ were increased in COPD patients in comparison with the patients without obstructive airway disorders(P<0.05).③The expression of NOX4 in ASM and epithelial cells of COPD patients was significantly higher in comparison with the patients without COPD. The expression of NOX4 in ASM of small airway were statistically different among different COPD grade (P<0.05). Correlation analysis demonstrated that the level of NOX4 protein in ASM of small airway was inversely associated with pulmonary functions. ④The expression of TGF-ß in COPD was significantly higher than that in patients without COPD. ⑤ Correlation analysis demonstrated that the level of NOX4 protein in ASM of small airway, WT% and WA% were inversely associated with pulmonary functions. CONCLUSIONS: ①The airway remodeling of COPD is characterized by increasing hyperplasia of small airway smooth muscle.②Remodeling of airway smooth muscle associats with severity of airflow limitation in COPD patients. ③The expressions of NOX4, TGF-ß and α-SMA in COPD epithelial cells and small airway smooth muscle cells are significantly enhanced. The expressions of NOX4, α-SMA and TGF-ß are positively correlated with the severity of chronic obstructive pulmonary air flow, suggesting that TGF-ß and NOX4 signaling may be involved in the development of chronic obstructive pulmonary disease airway remodeling.