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Fibroblasts play a central role in the lung fibrotic process. Our recent study identified a novel subpopulation of lung fibroblasts expressing meflin (mesenchymal stromal cell- and fibroblast-expressing Linx paralogue), antifibrotic properties of which were confirmed by murine lung fibrosis model. Meflin-expressing fibroblasts were resistant to fibrogenesis induced by TGF-β (transforming growth factor-β), but its underlying mechanisms remain unknown. In this study, evaluation of a silica-nanoparticle-induced lung fibrosis model confirmed the antifibrotic effect of meflin via the regulation of TGF-β signaling. We conducted comparative gene expression profiling in lung fibroblasts, which identified growth differentiation factor 10 (iGdf10/i) encoding bone morphogenic protein 3b (BMP3b) as the most downregulated gene in meflin-deficient cells under the profibrotic condition with TGF-β. We hypothesized that BMP3b can be an effector molecule playing an antifibrotic role downstream of meflin. As suggested by single-cell transcriptomic data, restricted expressions ofiGdf10 (Bmp3b)/iin stromal cells including fibroblasts were confirmed. We examined possible antifibrotic properties of BMP3b in lung fibroblasts and demonstrated thatiBmp3b/i-null fibroblasts were more susceptible to TGF-β-induced fibrogenic changes. Furthermore,iBmp3b/i-null mice exhibited exaggerated lung fibrosis induced by silica-nanoparticlesiin vivo/i. We also demonstrated that treatment with recombinant BMP3B was effective against TGF-β-induced fibrogenesis in fibroblasts, especially in the suppression of excessive extracellular matrix production. These lines of evidence suggested that BMP3b is a novel humoral effector molecule regulated by meflin which exerts antifibrotic properties in lung fibroblasts. Supplementation of BMP3B could be a novel therapeutic strategy for fibrotic lung diseases.

We herein report a case of acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF) triggered by COVID-19. An 87-year-old woman tested positive for COVID-19 on a polymerase chain reaction test, and computed tomography revealed ground-glass opacity (GGO) superimposed on a background pattern consistent with usual interstitial pneumonia. Considering these data, we diagnosed her with AE-IPF. She experienced worsening of dyspnea and expansion of the GGO. Therefore, we introduced high-dose steroids (methylprednisolone 250 mg/day for 3 days). After the treatment, the pulmonary infiltrates improved. She was discharged from our hospital without severe disability. High-dose steroids can be a viable treatment option for AE-IPF triggered by COVID-19.

This prospective observational cohort study was performed to investigate the physical function and mental health trajectories of novel coronavirus disease 2019 (COVID-19) patients requiring invasive mechanical ventilation (IMV) after discharge from the intensive care unit (ICU). The study population consisted of 64 patients (median age, 60 years; 85.9% male; median IMV duration, 9 days). At ICU discharge, 28.1% of the patients had Medical Research Council (MRC) sum score

Supplemental Digital Content is available in the text., Background: Cellular diversity of the lung endothelium has not been systematically characterized in humans. We provide a reference atlas of human lung endothelial cells (ECs) to facilitate a better understanding of the phenotypic diversity and composition of cells comprising the lung endothelium. Methods: We reprocessed human control single-cell RNA sequencing (scRNAseq) data from 6 datasets. EC populations were characterized through iterative clustering with subsequent differential expression analysis. Marker genes were validated by fluorescent microscopy and in situ hybridization. scRNAseq of primary lung ECs cultured in vitro was performed. The signaling network between different lung cell types was studied. For cross-species analysis or disease relevance, we applied the same methods to scRNAseq data obtained from mouse lungs or from human lungs with pulmonary hypertension. Results: Six lung scRNAseq datasets were reanalyzed and annotated to identify >15 000 vascular EC cells from 73 individuals. Differential expression analysis of EC revealed signatures corresponding to endothelial lineage, including panendothelial, panvascular, and subpopulation-specific marker gene sets. Beyond the broad cellular categories of lymphatic, capillary, arterial, and venous ECs, we found previously indistinguishable subpopulations; among venous EC, we identified 2 previously indistinguishable populations: pulmonary–venous ECs (COL15A1neg) localized to the lung parenchyma and systemic–venous ECs (COL15A1pos) localized to the airways and the visceral pleura; among capillary ECs, we confirmed their subclassification into recently discovered aerocytes characterized by EDNRB, SOSTDC1, and TBX2 and general capillary EC. We confirmed that all 6 endothelial cell types, including the systemic–venous ECs and aerocytes, are present in mice and identified endothelial marker genes conserved in humans and mice. Ligand-receptor connectome analysis revealed important homeostatic crosstalk of EC with other lung resident cell types. scRNAseq of commercially available primary lung ECs demonstrated a loss of their native lung phenotype in culture. scRNAseq revealed that endothelial diversity is maintained in pulmonary hypertension. Our article is accompanied by an online data mining tool (www.LungEndothelialCellAtlas.com). Conclusions: Our integrated analysis provides a comprehensive and well-crafted reference atlas of ECs in the normal lung and confirms and describes in detail previously unrecognized endothelial populations across a large number of humans and mice.

Idiopathic Pulmonary Fibrosis (IPF) is a chronic, progressive, and often fatal disorder. Two FDA approved anti-fibrotic drugs, nintedanib and pirfenidone, slow the rate of decline in lung function, but responses are variable and side effects are common. Using an in-silico data-driven approach, we identified a robust connection between the transcriptomic perturbations in IPF disease and those induced by saracatinib, a selective Src kinase inhibitor, originally developed for oncological indications. Based on these observations, we hypothesized that saracatinib would be effective at attenuating pulmonary fibrosis. We investigated the anti-fibrotic efficacy of saracatinib relative to nintedanib and pirfenidone in three preclinical models: (i) in vitro in normal human lung fibroblasts (NHLFs); (ii) in vivo in bleomycin and recombinant adenovirus transforming growth factor-beta (Ad-TGF-β) murine models of pulmonary fibrosis; and (iii) ex vivo in precision cut lung slices from these mouse models. In each model, the effectiveness of saracatinib in blocking fibrogenic responses was equal or superior to nintedanib and pirfenidone.

Coronavirus disease 2019 (COVID-19) is a recently-emerged infectious disease that has caused millions of deaths, where comprehensive understanding of disease mechanisms is still unestablished. In particular, studies of gene expression dynamics and regulation landscape in COVID-19 infected individuals are limited. Here, we report on a thorough analysis of whole blood RNA-seq data from 465 genotyped samples from the Japan COVID-19 Task Force, including 359 severe and 106 non-severe COVID-19 cases. We discover 1169 putative causal expression quantitative trait loci (eQTLs) including 34 possible colocalizations with biobank fine-mapping results of hematopoietic traits in a Japanese population, 1549 putative causal splice QTLs (sQTLs; e.g. two independent sQTLs at TOR1AIP1), as well as biologically interpretable trans-eQTL examples (e.g., REST and STING1), all fine-mapped at single variant resolution. We perform differential gene expression analysis to elucidate 198 genes with increased expression in severe COVID-19 cases and enriched for innate immune-related functions. Finally, we evaluate the limited but non-zero effect of COVID-19 phenotype on eQTL discovery, and highlight the presence of COVID-19 severity-interaction eQTLs (ieQTLs; e.g., CLEC4C and MYBL2). Our study provides a comprehensive catalog of whole blood regulatory variants in Japanese, as well as a reference for transcriptional landscapes in response to COVID-19 infection., 「コロナ制圧タスクフォース」COVID-19患者由来の血液細胞における遺伝子発現の網羅的解析 --重症度に応じた遺伝子発現の変化には、ヒトゲノム配列の個人差が影響する--. 京都大学プレスリリース. 2022-08-23.

Whether a patient with severe coronavirus disease (COVID-19) will be successfully liberated from mechanical ventilation (MV) early is important in the COVID-19 pandemic. This study aimed to characterize the time course of parameters and outcomes of severe COVID-19 in relation to the timing of liberation from MV. This retrospective, single-center, observational study was performed using data from mechanically ventilated COVID-19 patients admitted to the ICU between 1 March 2020 and 15 December 2020. Early liberation from ventilation (EL group) was defined as successful extubation within 10 days of MV. The trends of respiratory mechanics and laboratory data were visualized and compared between the EL and prolonged MV (PMV) groups using smoothing spline and linear mixed effect models. Of 52 admitted patients, 31 mechanically ventilated COVID-19 patients were included (EL group, 20 (69%), PMV group, 11 (31%)). The patients’ median age was 71 years. While in-hospital mortality was low (6%), activities of daily living (ADL) at the time of hospital discharge were significantly impaired in the PMV group compared to the EL group (mean Barthel index (range): 30 (7.5–95) versus 2.5 (0–22.5), p = 0.048). The trends in respiratory compliance were different between patients in the EL and PMV groups. An increasing trend in the ventilatory ratio during MV until approximately 2 weeks was observed in both groups. The interaction between daily change and earlier liberation was significant in the trajectory of the thrombin–antithrombin complex, antithrombin 3, fibrinogen, C-reactive protein, lymphocyte, and positive end-expiratory pressure (PEEP) values. The indicator of physiological dead space increases during MV. The trajectory of markers of the hypercoagulation status, inflammation, and PEEP were significantly different depending on the timing of liberation from MV. These findings may provide insight into the pathophysiology of COVID-19 during treatment in the critical care setting.

Activation of transforming growth factor β (TGF‐β) combined with persistent hypoxia often affects the tumor microenvironment. Disruption of cadherin/catenin complexes induced by these stimulations yields aberrant extracellular matrix (ECM) production, characteristics of epithelial‐mesenchymal transition (EMT). Hypoxia‐inducible factors (HIF), the hallmark of the response to hypoxia, play differential roles during development of diseases. Recent studies show that localization of cadherin/catenin complexes at the cell membrane might be tightly regulated by protein phosphatase activity. We aimed to investigate the role of stabilized HIF‐1α expression by protein phosphatase activity on dissociation of the E‐cadherin/β‐catenin complex and aberrant ECM expression in lung cancer cells under stimulation by TGF‐β. By using lung cancer cells treated with HIF‐1α stabilizers or carrying doxycycline‐dependent HIF‐1α deletion or point mutants, we investigated the role of stabilized HIF‐1α expression on TGF‐β‐induced EMT in lung cancer cells. Furthermore, the underlying mechanisms were determined by inhibition of protein phosphatase activity. Persistent stimulation by TGF‐β and hypoxia induced EMT phenotypes in H358 cells in which stabilized HIF‐1α expression was inhibited. Stabilized HIF‐1α protein expression inhibited the TGF‐β‐stimulated appearance of EMT phenotypes across cell types and species, independent of de novo vascular endothelial growth factor A (VEGFA) expression. Inhibition of protein phosphatase 2A activity abrogated the HIF‐1α‐induced repression of the TGF‐β‐stimulated appearance of EMT phenotypes. This is the first study to show a direct role of stabilized HIF‐1α expression on inhibition of TGF‐β‐induced EMT phenotypes in lung cancer cells, in part, through protein phosphatase activity.

Squamous cell carcinoma (SCC) transformation has been identified as a mechanism of resistance to first-generation epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs), gefitinib or erlotinib, in EGFR-mutated lung cancer. However, whether second- or third-generation TKIs can overcome resistance due to SCC transformation remains unclear. We herein report an EGFR-mutated lung adenocarcinoma undergoing transformation into SCC that exhibited a durable response to afatinib, which is a second-generation irreversible EGFR-TKI. We suggest that afatinib can be considered as a treatment option for EGFR-mutated tumor undergoing SCC transformation, particularly in the absence of a T790M mutation.

To elucidate the host genetic loci affecting severity of SARS-CoV-2 infection, or Coronavirus disease 2019 (COVID-19), is an emerging issue in the face of the current devastating pandemic. Here, we report a genome-wide association study (GWAS) of COVID-19 in a Japanese population led by the Japan COVID-19 Task Force, as one of the initial discovery GWAS studies performed on a non-European population. Enrolling a total of 2,393 cases and 3,289 controls, we not only replicated previously reported COVID-19 risk variants (e.g., LZTFL1, FOXP4, ABO, and IFNAR2), but also found a variant on 5p35 (rs60200309-A at DOCK2) that was significantly associated with severe COVID-19 in younger (-8 (odds ratio = 2.01, 95% confidence interval = 1.58-2.55). This risk allele was prevalent in East Asians, including Japanese (minor allele frequency [MAF] = 0.097), but rarely found in Europeans. Cross-population Mendelian randomization analysis made a causal inference of a number of complex human traits on COVID-19. In particular, obesity had a significant impact on severe COVID-19. The presence of the population-specific risk allele underscores the need of non-European studies of COVID-19 host genetics.

Chronic Obstructive Pulmonary Disease (COPD) is a leading cause of death worldwide. To identify cell-specific mechanisms underlying COPD pathobiology, we analysed single-cell RNA sequencing (scRNAseq) profiles of explanted lung tissue from subjects with advanced COPD or control lungs. Findings were validated with scRNAseq of lungs from mice exposed to 10 months of cigarette smoke (CS), isolated human alveolar epithelial cells, and immunostaining of human lung tissue samples. We identified a subpopulation of alveolar epithelial type II cells with transcriptional evidence for aberrant cellular metabolism and reduced cellular stress tolerance, exemplified by decreased expression of the stress-response gene NUPR1. Network analyses identified an important role for inflamed capillary endothelial cells in COPD, particularly through CXCL-motif chemokine signalling. Finally, we detected a metallothionein expressing macrophage subpopulation unique to COPD. Collectively, these findings highlight cell-specific mechanisms involved in the pathobiology of advanced COPD.

Long‐noncoding RNAs (lncRNAs) have numerous biological functions controlling cell differentiation and tissue development. The knowledge about the role of lncRNAs in human lungs remains limited. Here we found the regulatory role of the terminal differentiation‐induced lncRNA (TINCR) in bronchial cell differentiation. RNA in situ hybridization revealed that TINCR was mainly expressed in bronchial epithelial cells in normal human lung. We performed RNA sequencing analysis of normal human bronchial epithelial cells (NHBECs) with or without TINCR inhibition and found the differential expression of 603 genes, which were enriched for cell adhesion and migration, wound healing, extracellular matrix organization, tissue development and differentiation. To investigate the role of TINCR in the differentiation of NHBECs, we employed air–liquid interface culture and 3D organoid formation assay. TINCR was upregulated during differentiation, loss of TINCR significantly induced an early basal‐like cell phenotype (TP63) and a ciliated cell differentiation (FOXJ1) in late phase and TINCR overexpression suppressed basal cell phenotype and the differentiation toward to ciliated cells. Critical regulators of differentiation such as SOX2 and NOTCH genes (NOTCH1, HES1, and JAG1) were significantly upregulated by TINCR inhibition and downregulated by TINCR overexpression. RNA immunoprecipitation assay revealed that TINCR was required for the direct bindings of Staufen1 protein to SOX2, HES1, and JAG1 mRNA. Loss of Staufen1 induced TP63, SOX2, NOTCH1, HES1, and JAG1 mRNA expressions, which TINCR overexpression suppressed partially. In conclusion, TINCR is a novel regular of bronchial cell differentiation, affecting downstream regulators such as SOX2 and NOTCH genes, potentially in coordination with Staufen1., Proposed model representing that TINCR together with STAU1 controls the expression of critical regulators of bronchial cell differentiation and maintains the normal differentiation state.

Cellular senescence is a cell fate implicated in the pathogenesis of idiopathic pulmonary fibrosis (IPF) and chronic obstructive pulmonary disease (COPD). Cellular senescence occurs in response to cellular stressors such as oxidative stress, DNA damage, telomere shortening, and mitochondrial dysfunction. Whether these stresses induce cellular senescence or an alternative cell fate depends on the type and magnitude of cellular stress, but also on intrinsic factors regulating the cellular stress response. Non-coding RNAs, including both microRNAs and long non-coding RNAs, are key regulators of cellular stress responses and susceptibility to cellular senescence. In this review, we will discuss cellular mechanisms that contribute to senescence in IPF and COPD and highlight recent advances in our understanding of how these processes are influenced by non-coding RNAs. We will also discuss the potential therapeutic role for targeting non-coding RNAs to treat these chronic lung diseases.

BackgroundDespite its importance in health and disease, the cellular diversity of the lung endothelium has not been systematically characterized in humans. Here we provide a reference atlas of human lung endothelial cells (ECs), to facilitate a better understanding of the phenotypic diversity and composition of cells comprising the lung endothelium, both in health and disease.MethodsWe reprocessed control single cell RNA sequencing (scRNAseq) data from five datasets of whole lungs that were used for the analysis of pan-endothelial markers, we later included a sixth dataset of sorted control EC for the vascular subpopulation analysis. EC populations were characterized through iterative clustering with subsequent differential expression analysis. Marker genes were validated by immunohistochemistry andin situhybridization. Signaling network between different lung cell types was studied using connectomic analysis. For cross species analysis we applied the same methods to scRNAseq data obtained from mouse lungs.ResultsThe six lung scRNAseq datasets were reanalyzed and annotated to identify over 15,000 vascular EC cells from 73 individuals. Differential expression analysis of EC revealed signatures corresponding to endothelial lineage, including pan-endothelial, pan-vascular and subpopulation-specific marker gene sets. Beyond the broad cellular categories of lymphatic, capillary, arterial and venous ECs we found previously indistinguishable subpopulations; among venous EC we identified two previously indistinguishable populations, pulmonary-venous ECs (COL15A1neg) localized to the lung parenchyma and systemic-venous ECs (COL15A1pos) localized to the airways and the visceral pleura; among capillary EC we confirmed their subclassification into recently discovered aerocytes characterized by EDNRB, SOSTDC1 and TBX2 and general capillary EC. We confirmed that all six endothelial cell types, including the systemic-venous EC and aerocytes are present in mice and identified endothelial marker genes conserved in humans and mice. Ligand-Receptor connectome analysis revealed important homeostatic crosstalk of EC with other lung resident cell types. Our manuscript is accompanied by an online data mining tool (www.LungEndothelialCellAtlas.com).ConclusionOur integrated analysis provides the comprehensive and well-crafted reference atlas of lung endothelial cells in the normal lung and confirms and describes in detail previously unrecognized endothelial populations across a large number of humans and mice.

Chronic Obstructive Pulmonary Disease (COPD) pathogenesis involves a failure to maintain alveolar homeostasis due to repetitive injury and inflammation. In order to improve our understanding of cell-specific mechanisms contributing to COPD pathogenesis, we analysed single-cell RNA sequencing (scRNAseq) profiles of explanted parenchymal lung tissue from 17 subjects with advanced COPD requiring transplant and 15 control donor lungs. We identified a subpopulation of alveolar type II epithelial cells that uniquely expressHHIPand have aberrant stress tolerance profiles in COPD. Amongst endothelial cells, we identified overlapping and unique shifts in transcriptional profiles of endothelial subtypes that may contribute to vascular inflammation and susceptibility to injury. We also identified population composition changes amongst alveolar macrophages. Finally, application of integrative analyses to our scRNAseq data identified cell-specific contributions to COPD heritability and dysfunctional cell-cell communication pathways that occur within the COPD alveolar niche. These findings provide cell type-specific resolution of transcriptional changes associated with advanced COPD that may underlie disease pathogenesis.

The prognosis of elderly individuals with idiopathic pulmonary fibrosis (IPF) remains poor. Fibroblastic foci, in which aggregates of proliferating fibroblasts and myofibroblasts are involved, are the pathological hallmark lesions in IPF to represent focal areas of active fibrogenesis. Fibroblast heterogeneity in fibrotic lesions hampers the discovery of the pathogenesis of pulmonary fibrosis. Therefore, to determine the pathogenesis of IPF, identification of functional fibroblasts is warranted. The aim of this study was to determine the role of fibroblasts positive for meflin, identified as a potential marker for mesenchymal stromal cells, during the development of pulmonary fibrosis.We characterised meflin-positive cells in a single-cell atlas established by single-cell RNA sequencing (scRNA-seq)-based profiling of 243 472 cells from 32 IPF lungs and 29 normal lung samples. We determined the role of fibroblasts positive for meflin using bleomycin (BLM)-induced pulmonary fibrosis.scRNA-seq combined with in situ RNA hybridisation identified proliferating fibroblasts positive for meflin in fibroblastic foci, not dense fibrosis, of fibrotic lungs in IPF patients. A BLM-induced lung fibrosis model for meflin-deficient mice showed that fibroblasts positive for meflin had anti-fibrotic properties to prevent pulmonary fibrosis. Although transforming growth factor-β-induced fibrogenesis and cell senescence with the senescence-associated secretory phenotype were exacerbated in fibroblasts via the repression or lack of meflin, these were inhibited in meflin-deficient fibroblasts with meflin reconstitution.These findings provide evidence to show the biological importance of meflin expression on fibroblasts and myofibroblasts in the active fibrotic region of pulmonary fibrosis.

BACKGROUND Lung-dominant connective tissue disease (LD-CTD) is a disease concept for interstitial pneumonia; however, it has not been robustly validated. /p study was conducted to elucidate the clinical, radiologic, and histologic features of LD-CTD. METHODS We retrospectively reviewed 44 consecutive patients with serologically defined LD-CTD who underwent surgical lung biopsy. Six were identified as having LD-CTD if they had specific autoantibodies but did not meet the criteria for connective tissue disease. We conducted a multidisciplinary diagnosis and evaluated major histologic patterns according to the current idiopathic interstitial pneumonias (IIPs) classification of 2013. Characteristic histologic features for LD-CTD (eg, prominent plasmacytic infiltration, lymphoid aggregates with germinal centers), high-resolution CT (HRCT) scan patterns, and prognosis were also assessed. METHODS The major histologic patterns were usual interstitial pneumonia (UIP) in 25 patients and nonspecific interstitial pneumonia (NSIP) in 13 patients. Two or more characteristic histologic features for LD-CTD were observed in 15 patients with histologic UIP (h-UIP) and 11 patients with histologic NSIP (h-NSIP). Fifteen patients with h-UIP (60%) showed an inconsistent UIP pattern on HRCT scan multidisciplinary discussion (MDD), 18 patients with h-UIP were labeled as having unclassifiable IIP. The annual change in percent predicted FVC improved significantly in patients with h-NSIP (P = .002), who also had better survival than those with h-UIP (P = .031). In contrast, survival was not associated with HRCT scan pattern (P = .79). CONCLUSIONS The major histologic patterns in LD-CTD were UIP followed by NSIP. Two-thirds of patients had characteristic histologic features for LD-CTD. A majority of patients with h-UIP were considered to have unclassifiable IIP based on MDD. Patients with h-UIP had worse survival than those with h-NSIP. CHEST 2015;148(6):1438-1446

Norihito Omote, Naozumi Hashimoto, Masahiro Morise, Koji Sakamoto, Shinichi Miyazaki, Akira Ando, Yoshio Nakahara, Yoshinori Hasegawa Department of Respiratory Medicine, Nagoya University Graduate School of Medicine, Nagoya, Japan Background: Non-small cell lung cancer (NSCLC) is the predominant cause of death in patients with COPD, and the severity of COPD in NSCLC patients is classified mainly as mild to moderate. Most advanced NSCLC patients with mild to moderate COPD are treated with chemotherapy; however, the feasibility for and prognosis after chemotherapy of these patients are not well understood. The aim of this study was to elucidate the impact of mild to moderate COPD on the feasibility for and prognosis after chemotherapy in NSCLC patients.Patients and methods: A retrospective review was performed on 268 NSCLC patients who received first-line chemotherapy from 2009 to 2014 in our institution. Finally, 85 evaluable patients were included in this study. The clinical characteristics, toxicity profile, objective response rate, and prognosis were analyzed and compared between patients with mild to moderate COPD and those without COPD (non-COPD).Results: Forty-three patients were classified as COPD (27 cases mild and 16 cases moderate) and 42 patients as non-COPD. The COPD group were older and had fewer never-smokers than the non-COPD group. The objective response rate did not differ between groups (p=0.14). There was no significant difference in overall survival between COPD and non-COPD groups (15.0 and 17.0 months, log-rank test p=0.57). In the multivariate Cox’s proportional hazard model, the adjusted hazard ratio (HRadj) was statistically significant for male sex (HRadj =5.382, 95% CI: 1.496–19.359; p=0.010), pathological diagnosis of adenocarcinoma (HRadj =0.460, 95% CI: 0.223–0.948; p=0.035), and epithelial growth factor receptor negative mutation (HRadj =6.040, 95% CI: 1.158–31.497; p=0.033), but not for the presence of COPD (HRadj =0.661, 95% CI: 0.330–1.325; p=0.24). Toxicity profile in COPD group was favorable, as in the non-COPD group.Conclusion: Mild to moderate COPD did not have a significant deleterious impact on toxicity and prognosis in NSCLC patients. Keywords: toxicity, survival, prognostic factors&nbsp

Rationale: Myofibroblasts are considered a disease hallmark of idiopathic pulmonary fibrosis (IPF). Recent research indicates the implication of redox imbalance and cellular senescence in the development of myofibroblasts in IPF. Long non-coding RNAs (lncRNAs), a novel class of epigenetic regulators, are attracting attentions as being involved in various biological processes. We recently discovered that FENDRR is among the the most decreased lncRNA in IPF. The aim of study is to test the hypothesis that FENDRR may be involved in myofibroblast differetiation in IPF. Methods & Results: In situ hybridization and immunohistochemistry in the serial sections of IPF lungs revealed that loss of FENDRR associated with increased cellular senescence in myofibroblasts in fibrotic foci. In vitro functional analysis revealed FENDRR depletion by si-RNAs induced differentiation of normal human lung fibroblasts (NHLFs) to myofibroblasts, which was accompanied by the cellular senescence and increased secretion of collagens and inflammatory mediators. We further assessed the involvement of altered redox balance, and found that FENDRR depletion increased intracellular ROS levels with augmented expression of NOX4. Suppression of NOX4 by siRNA reversed the differentiation into myofibroblast as assessed by α-SMA expression in FENDRR-depleted NHLFs. Conclusions: Decreased FENDRR expression may confer the altered phenotypes such as myofibroblastic differentiation and cellular senescence in IPF fibroblasts. Imbalanced redox balance, possibly through increased NOX4 levels may be involved in the mechanism.

Transforming growth factor β (TGFβ) causes the acquisition of epithelial-mesenchymal transition (EMT). Although the tumor suppressor gene PTEN (phosphatase and tensin homologue deleted from chromosome 10) can negatively regulate many signaling pathways activated by TGFβ, hyperactivation of these signaling pathways is observed in lung cancer cells. We recently showed that PTEN might be subject to TGFβ-induced phosphorylation of its C-terminus, resulting in a loss of its enzyme activities; PTEN with an unphosphorylated C-terminus (PTEN4A), but not PTEN wild, inhibits TGFβ-induced EMT. Nevertheless, whether or not the blockade of TGFβ-induced EMT by the PTEN phosphatase activity might be attributed to the unphosphorylated PTEN C-terminus itself has not been fully determined. Furthermore, the lipid phosphatase activity of PTEN is well characterized, whereas the protein phosphatase activity has not been determined. By using lung cancer cells carrying PTEN domain deletions or point mutants, we investigated the role of PTEN protein phosphatase activities on TGFβ-induced EMT in lung cancer cells. The unphosphorylated PTEN C-terminus might not directly retain the phosphatase activities and repress TGFβ-induced EMT; the modification that keeps the PTEN C-terminus not phosphorylated might enable PTEN to retain the phosphatase activity. PTEN4A with G129E mutation, which lacks lipid phosphatase activity but retains protein phosphatase activity, repressed TGFβ-induced EMT. Furthermore, the protein phosphatase activity of PTEN4A depended on an essential association between the C2 and phosphatase domains. These data suggest that the protein phosphatase activity of PTEN with an unphosphorylated C-terminus might be a therapeutic target to negatively regulate TGFβ-induced EMT in lung cancer cells.

Lung-dominant connective tissue disease (LD-CTD) is a disease concept for interstitial pneumonia; however, it has not been robustly validated. This study was conducted to elucidate the clinical, radiologic, and histologic features of LD-CTD.We retrospectively reviewed 44 consecutive patients with serologically defined LD-CTD who underwent surgical lung biopsy. Patients were identified as having LD-CTD if they had specific autoantibodies but did not meet the criteria for connective tissue disease. We conducted a multidisciplinary diagnosis and evaluated major histologic patterns according to the current idiopathic interstitial pneumonias (IIPs) classification of 2013. Characteristic histologic features for LD-CTD (eg, prominent plasmacytic infiltration, lymphoid aggregates with germinal centers), high-resolution CT (HRCT) scan patterns, and prognosis were also assessed.The major histologic patterns were usual interstitial pneumonia (UIP) in 25 patients and nonspecific interstitial pneumonia (NSIP) in 13 patients. Two or more characteristic histologic features for LD-CTD were observed in 15 patients with histologic UIP (h-UIP) and 11 patients with histologic NSIP (h-NSIP). Fifteen patients with h-UIP (60%) showed an inconsistent UIP pattern on HRCT scan. After multidisciplinary discussion (MDD), 18 patients with h-UIP were labeled as having unclassifiable IIP. The annual change in percent predicted FVC improved significantly in patients with h-NSIP (P = .002), who also had better survival than those with h-UIP (P = .031). In contrast, survival was not associated with HRCT scan pattern (P = .79).The major histologic patterns in LD-CTD were UIP followed by NSIP. Two-thirds of patients had characteristic histologic features for LD-CTD. A majority of patients with h-UIP were considered to have unclassifiable IIP based on MDD. Patients with h-UIP had worse survival than those with h-NSIP.

Mortality in patients with pulmonary tuberculosis remains high, especially in those who develop acute respiratory distress syndrome (ARDS). We report on a-48-year-old man with ARDS due to severe pulmonary tuberculosis who was rescued by extracorporeal membrane oxygenation (ECMO). He was initially hospitalized in the intensive care unit and noninvasive positive-pressure ventilation started. He was also administered anti-tuberculosis drugs and received systemic corticosteroid therapy. Six days later, further deterioration of gas exchange prompted the decision to intubate. However, he experienced progressive deterioration of arterial oxygenation despite conventional ventilatory support. We therefore decided to administer ECMO on day 9. After initiation of these treatments and ECMO support, pulmonary infiltrate and oxygenation status gradually improved and ECMO was discontinued on day 52. The patient was finally discharged from our hospital without severe disability. ECMO should be considered one of the treatment options for the management of ARDS due to severe pulmonary tuberculosis.

Background Persistent hypoxia stimulation, one of the most critical microenvironmental factors, accelerates the acquisition of epithelial–mesenchymal transition (EMT) phenotypes in lung cancer cells. Loss of phosphatase and tensin homologue deleted from chromosome 10 (PTEN) expression might accelerate the development of lung cancer in vivo. Recent studies suggest that tumor microenvironmental factors might modulate the PTEN activity though a decrease in total PTEN expression and an increase in phosphorylation of the PTEN C-terminus (p-PTEN), resulting in the acquisition of the EMT phenotypes. Nevertheless, it is not known whether persistent hypoxia can modulate PTEN phosphatase activity or whether hypoxia-induced EMT phenotypes are negatively regulated by the PTEN phosphatase activity. We aimed to investigate hypoxia-induced modulation of PTEN activity and EMT phenotypes in lung cancers. Methods Western blotting was performed in five lung cancer cell lines to evaluate total PTEN expression levels and the PTEN activation. In a xenograft model of lung cancer cells with endogenous PTEN expression, the PTEN expression was evaluated by immunohistochemistry. To examine the effect of hypoxia on phenotypic alterations in lung cancer cells in vitro, the cells were cultured under hypoxia. The effect of unphosphorylated PTEN (PTEN4A) induction on hypoxia-induced EMT phenotypes was evaluated, by using a Dox-dependent gene expression system. Results Lung cancer cells involving the EMT phenotypes showed a decrease in total PTEN expression and an increase in p-PTEN. In a xenograft model, loss of PTEN expression was observed in the tumor lesions showing tissue hypoxia. Persistent hypoxia yielded an approximately eight-fold increase in the p-PTEN/PTEN ratio in vitro. PTEN4A did not affect stabilization of hypoxia-inducible factor 1α. PTEN4A blunted hypoxia-induced EMT via inhibition of β-catenin translocation into the cytoplasm and nucleus. Conclusion Our study strengthens the therapeutic possibility that compensatory induction of unphosphorylated PTEN may inhibit the acquisition of EMT phenotypes in lung cancer cells under persistent hypoxia.