Search

Non-typeable Haemophilus influenzae (NTHi) is the most common respiratory pathogen in patients with chronic obstructive disease. Limited data is available investigating the impact of NTHi infections on cellular re-differentiation processes in the bronchial mucosa. The aim of this study was to assess the effects of stimulation with NTHi on the bronchial epithelium regarding cellular re-differentiation processes using primary bronchial epithelial cells harvested from infection-free patients undergoing bronchoscopy. The cells were then cultivated using an air-liquid interface and stimulated with NTHi and TGF-β. Markers of epithelial and mesenchymal cells were analyzed using immunofluorescence, Western blot and qRT-PCR. Stimulation with both NTHi and TGF-ß led to a marked increase in the expression of the mesenchymal marker vimentin, while E-cadherin as an epithelial marker maintained a stable expression throughout the experiments. Furthermore, expression of collagen 4 and the matrix-metallopeptidases 2 and 9 were increased after stimulation, while the expression of tissue inhibitors of metallopeptidases was not affected by pathogen stimulation. In this study we show a direct pathogen-induced trans-differentiation of primary bronchial epithelial cells resulting in a co-localization of epithelial and mesenchymal markers and an up-regulation of extracellular matrix components.

Background: Lung cancer is the most frequent cause of cancer-related deaths worldwide. The clinical development of immune checkpoint blockade has dramatically changed the treatment paradigm for patients with lung cancer. Yet, an improved understanding of PD-1/PD-L1 checkpoint blockade-responsive biology is warranted. Methods: We aimed to identify the landscape of immune cell infiltration in primary lung adenocarcinoma (LUAD) in the context of tumoral PD-L1 expression and the extent of immune infiltration (“hot” vs. “cold” phenotype). The study comprises LUAD cases (n = 138) with “hot” (≥150 lymphocytes/HPF) and “cold” (&lt, 150 lymphocytes/HPF) tumor immune phenotype and positive (&gt, 50%) and negative (&lt, 1%) tumor PD-L1 expression, respectively. Tumor samples were immunohistochemically analyzed for expression of PD-L1, CD4, and CD8, and further investigated by transcriptome analysis. Results: Gene set enrichment analysis defined complement, IL-JAK-STAT signaling, KRAS signaling, inflammatory response, TNF-alpha signaling, interferon-gamma response, interferon-alpha response, and allograft rejection as significantly upregulated pathways in the PD-L1-positive hot subgroup. Additionally, we demonstrated that STAT1 is upregulated in the PD-L1-positive hot subgroup and KIT in the PD-L1-negative hot subgroup. Conclusion: The presented study illustrates novel aspects of PD-L1 regulation, with potential biological relevance, as well as relevance for immunotherapy response stratification.

Introduction: cAMP response element-binding protein (CREB) mediates proliferative and inflammatory transcription in neurodegeneration and cancer, but its role in malignant immune-evasion is obscure. Objectives: To discover the mechanisms underlying the oncogenic properties of CREB in KRAS-mutant lung adenocarcinoma (LUAD). Materials and Methods: We used conditional deletion, focal overexpression, and pharmacologic inhibition of CREB in different mouse and cellular models of early-stage and metastatic KRAS-mutant LUAD. We determined the neutrophil (ΝΦ) influx in the bronchoalveolar lavage (BAL) from LUAD-affected conditionally Creb1-deleted lungs. We employed The Cancer Genome Atlas, the GEO dataset GSE43458, and the human protein atlas to examine CREB and CXCR1 in human LUAD. Results: CREB is overexpressed in murine KRAS-mutant LUAD, pulmonary deletion of Creb1 (encoding murine CREB) inhibits LUAD development, and Creb1-overexpression augments the tumorigenicity of KRAS-mutant cells. Conditional Creb1 deletion in KRAS -mutant LUAD cells causes overexpression of CXCR1 ligands, and LUAD-bearing Creb1-deleted mice display increased pulmonary ΝΦ. Cxcr1-deficient mice are selectively permissive to KRAS-mutant tumor growth and show defective ΝΦ recruitment. The pro-tumor effects of CREB require intact host Cxcr1 and those of host Cxcr1 necessitate mutant KRAS in cancer cells. Pharmacologic CREB blockade prevents tumor growth and restores ΝΦ recruitment only when initiated before immune-evasion of KRAS-mutant LUAD. CREB and CXCR1 expression of human LUAD are compartmentalized to tumor and stromal cells, respectively, while CREB-controlled genes profoundly impact survival. Conclusions: CREB-mediated immune evasion of KRAS-mutant LUAD rests on signaling to ΝΦ CXCR1 and is actionable.

cAMP response element-binding protein (CREB) mediates proliferative and inflammatory gene transcription in neurodegeneration and cancer, but its role in malignant immune-evasion of lung adenocarcinoma (LUAD) is unknown. We show that human LUAD of smokers are frequently altered along the CREB pathway and we employ mouse models to discover that KRAS-mutant LUAD co- opt CREB to evade immune rejection by tumoricidal neutrophils. For this, KRAS- driven CREB activation suppresses CXC-chemokine expression and prevents recruitment of CXCR1+ neutrophils. CREB1 is shown to be pro-tumorigenic in five different LUAD models, a function that is dependent on host CXCR1. Pharmacologic CREB blockade prevents tumor growth and restores neutrophil recruitment only when initiated before immune-evasion of KRAS-mutant LUAD. CREB and CXCR1 expression in human LUAD are compartmentalized to tumor and stromal cells, respectively, while CREB-regulated genes and neutrophils impact survival. In summary, CREB-mediated immune evasion of KRAS-mutant LUAD relies on signaling to neutrophil CXCR1 and is actionable.

Introduction: cAMP response element-binding protein (CREB) mediates proliferative and inflammatory transcription in neurodegeneration and cancer, but its role in malignant immune-evasion is obscure. Objectives: To discover the mechanisms underlying the oncogenic properties of CREB in KRAS-mutant lung adenocarcinoma (LUAD). Materials and Methods: We used conditional deletion, focal overexpression, and pharmacologic inhibition of CREB in different mouse and cellular models of early-stage and metastatic KRAS-mutant LUAD. We determined the neutrophil (ΝΦ) influx in the bronchoalveolar lavage (BAL) from LUAD-affected conditionally Creb1-deleted lungs. We employed The Cancer Genome Atlas, the GEO dataset GSE43458, and the human protein atlas to examine CREB and CXCR1 in human LUAD. Results: CREB is overexpressed in murine KRAS-mutant LUAD, pulmonary deletion of Creb1 (encoding murine CREB) inhibits LUAD development, and Creb1-overexpression augments the tumorigenicity of KRAS-mutant cells. Conditional Creb1 deletion in KRAS -mutant LUAD cells causes overexpression of CXCR1 ligands, and LUAD-bearing Creb1-deleted mice display increased pulmonary ΝΦ. Cxcr1-deficient mice are selectively permissive to KRAS-mutant tumor growth and show defective ΝΦ recruitment. The pro-tumor effects of CREB require intact host Cxcr1 and those of host Cxcr1 necessitate mutant KRAS in cancer cells. Pharmacologic CREB blockade prevents tumor growth and restores ΝΦ recruitment only when initiated before immune-evasion of KRAS-mutant LUAD. CREB and CXCR1 expression of human LUAD are compartmentalized to tumor and stromal cells, respectively, while CREB-controlled genes profoundly impact survival. Conclusions: CREB-mediated immune evasion of KRAS-mutant LUAD rests on signaling to ΝΦ CXCR1 and is actionable.

In vitro, animal model and anecdotal clinical evidence suggests that tuberculosis (TB) is not a monomorphic disease, and that host response to TB is protean with multiple distinct molecular pathways and pathologies (endotypes). We used unbiased clustering to identify separate TB endotypes with distinctive gene expression patterns and different clinical outcomes. A discovery cohort that included 443 TB patients and 527 asymptomatic controls identified two TB endotypes exhibiting distinct gene expression in proliferation, metabolism, and immune pathways. Specifically, TB patient endotype A was characterized by increased expression of genes related to inflammation and immunity and decreased metabolism and proliferation; in contrast, endotype B expressed increased pathways related to metabolism and proliferation. The endotype signatures were validated using an independent RNA-seq validation cohort consisting of two studies that included 118 TB patients and 208 controls. A second validation cohort confirmed differential pathway activity between TB endotypes and demonstrated that TB patients in endotype A had slower time to culture conversion, increased risk of death, and increased risk of poor clinical outcomes. These observations suggest that endotypes reflect different functional immunity; this postulate was further supported by the observation that TB patients with the hyperinflammatory endotype showed hyporesponsive cytokine and chemokine responses. Collectively, these findings provide further evidence that metabolic and immune profiling could inform and optimize targeted endotype-specific therapies for TB.

Gene amplification is considered to be one responsible cause for upregulation of Programmed Death Ligand-1 (PD-L1) in non-small cell lung cancer (NSCLC) and to represent a specific molecular subgroup possibly associated with immunotherapy response. Our aim was to analyze the frequency of PD-L1 amplification, its relation to PD-L1 mRNA and protein expression, and to characterize the immune microenvironment of amplified cases. The study was based on two independent NSCLC cohorts, including 354 and 349 cases, respectively. Tissue microarrays were used to evaluate PD-L1 amplification by FISH and PD-L1 protein by immunohistochemistry. Immune infiltrates were characterized immunohistochemically by a panel of immune markers (CD3, CD4, CD8, PD-1, Foxp3, CD20, CD138, CD168, CD45RO, NKp46). Mutational status was determined by targeted sequencing. RNAseq data was available for 197 patients. PD-L1 amplification was detected in 4.5% of all evaluable cases. PD-L1 amplification correlated only weakly with mRNA and protein expression. About 37% of amplified cases were negative for PD-L1 protein. PD-L1 amplification did not show any association with the mutational status. In squamous cell cancer, PD-L1 amplified cases were enriched among patients with high tumoral immune cell infiltration and showed gene expression profiles related to immune exhaustion. In conclusion, PD-L1 amplification correlates with PD-L1 expression in squamous cell cancer and was associated with an immune cell rich tumor phenotype. The correlative findings help to understand the role of PD-L1 amplification as an important immune escape mechanism in NSCLC and suggest the need to further evaluate PD-L1 amplification as predictive biomarker for checkpoint inhibitor therapy. Supplementary Information The online version contains supplementary material available at 10.1007/s00262-020-02825-z.

Although immune checkpoint and targeted therapies offer remarkable benefits for lung cancer treatment, some patients do not qualify for these regimens or do not exhibit consistent benefit. Provided that lung cancer appears to be driven by transforming growth factor beta signaling, we investigated the single drug potency of Pirfenidone, an approved drug for the treatment of lung fibrosis. Five human lung cancer cell lines and one murine line were investigated for transforming growth factor beta inhibition via Pirfenidone by using flow cytometry, In-Cell western analysis, proliferation assays as well as comprehensive analyses of the transcriptome with subsequent bioinformatics analysis. Overall, Pirfenidone induced cell cycle arrest, down-regulated SMAD expression and reduced proliferation in lung cancer. Furthermore, cell stress pathways and pro-apoptotic signaling may be mediated by reduced expression of Survivin. A murine subcutaneous model was used to assess the in vivo drug efficacy of Pirfenidone and showed reduced tumor growth and increased infiltration of T cells and NK cells. This data warrant further clinical evaluation of Pirfenidone with advanced non-small cell lung cancer. The observed in vitro and in vivo effects point to a substantial benefit for using Pirfenidone to reactivate the local immune response and possible application in conjunction with current immunotherapies.

BackgroundThe interplay of immune and cancer cells takes place in the tumor microenvironment where multiple signals are exchanged. The transforming growth factor beta (TGFB) pathway is known to be dysregulated in lung cancer and can impede an effective immune response. However, the exact mechanisms are yet to be determined. Especially which cells respond and where does this signaling take place with respect to the local microenvironment.MethodsHuman non-small cell lung cancer samples were retrospectively analyzed by multiplexed immunohistochemistry for SMAD3 phosphorylation and programmed death ligand 1 expression in different immune cells with respect to their localization within the tumor tissue. Spatial relationships were studied to examine possible cell-cell interactions and analyzed in conjunction with clinical data.ResultsTGFB pathway activation in CD3, CD8, Foxp3 and CD68 cells, as indicated by SMAD3 phosphorylation, negatively impacts overall and partially disease-free survival of patients with lung cancerindependent of histological subtype. A high frequency of Foxp3 regulatory T cells positive for SMAD3 phosphorylation in close vicinity of CD8 T cells within the tumor discriminate a rapidly progressing group of patients with lung cancer.ConclusionsTGFB pathway activation of local immune cells within the tumor microenvironment impacts survival of early stage lung cancer. This might benefit patients not eligible for targeted therapies or immune checkpoint therapy as a therapeutic option to re-activate the local immune response.

Non–small cell lung cancer (NSCLC) is characterized by early metastasis and has the highest mortality rate among all solid tumors, with the majority of patients diagnosed at an advanced stage where curative therapeutic options are lacking. In this study, we identify a targetable mechanism involving TGFβ elevation that orchestrates tumor progression in this disease. Substantial activation of this pathway was detected in human lung cancer tissues with concomitant downregulation of BAMBI, a negative regulator of the TGFβ signaling pathway. Alterations of epithelial-to-mesenchymal transition (EMT) marker expression were observed in lung cancer samples compared with tumor-free tissues. Distinct alterations in the DNA methylation of the gene regions encoding TGFβ pathway components were detected in NSCLC samples compared with tumor-free lung tissues. In particular, epigenetic silencing of BAMBI was identified as a hallmark of NSCLC. Reconstitution of BAMBI expression in NSCLC cells resulted in a marked reduction of TGFβ-induced EMT, migration, and invasion in vitro, along with reduced tumor burden and tumor growth in vivo. In conclusion, our results demonstrate how BAMBI downregulation drives the invasiveness of NSCLC, highlighting TGFβ signaling as a candidate therapeutic target in this setting. Cancer Res; 76(13); 3785–801. ©2016 AACR.

Targeting checkpoint inhibitors using monoclonal antibodies results in significantly better outcome of cancer patients compared to conventional chemotherapy. However, the current companion diagnostics to predict response is so far suboptimal, since they base on more or less reliable immunohistochemical approaches. In order to overcome these limitations, we analyzed epigenetic modifications of PDCD1 (PD1), CD274 (PD-L1), and CTLA4 in NSCLC tissues from 39 patients. Results were correlated with transcriptome data. Significant differences in the CpG-methylation patterns between tumor tissues and matched controls were observed for CTLA4 and PDCD1 (PD1) showing a decreased methylation of these genes compared to matched tumor-free tissues from the same patients. Results were confirmed by bisulfide sequencing in an independent validation cohort. Hypomethylation also resulted in increased expression of these genes as shown by transcriptome data. These epigenetic pathways as a hallmark of NSCLC might be useful to generate more precise diagnostic approaches in the future.

COPD is characterized by neutrophilic airway inflammation. Neutrophil extracellular trap formation (NETosis), which consists of extracellular neutrophilic DNA, histones and granule enzymes, such as neutrophil elastase may regulate innate immune responses and potentially contribute to neutrophil-associated diseases. The presence of NETosis in sputum of stable COPD patients remains unknown. The aim of this study was to determine the level of NET formation in induced sputum from patients with COPD and to examine its relationship with sputum neutrophilia and airway obstruction. We evaluated induced sputum samples of 23 COPD patients (mean age, 67.0 ± 8.1 years; mean FEV1, 57.8 ± 16.6% pred.) and 10 healthy controls (mean age 55.0 ± 16.6 years) in whom airway obstruction were assessed using lung function testing. Sputum cells were harvested and stained with anti-histone H1, anti-neutrophil-elastase and DAPI. Concentration of extracellular DNA in sputum supernatants was quantified using a NanoDrop 2000 spectrophotometer. NETosis was markedly upregulated in COPD sputum compared with healthy controls as evaluated by immunofluorescence microscopy. NETosis was associated with significantly higher concentration of extracelluar DNA in sputum supernatant (mean 656.0 ± 894.6 ng/µL in COPD versus 300.2 ± 216.0 ng/µl in controls, p

Histological and clinical investigations describe late stages of Legionnaires' disease but cannot characterize early events of human infection. Cellular or rodent infection models lack the complexity of tissue or have nonhuman backgrounds. Therefore, we developed and applied a novel model for Legionella pneumophila infection comprising living human lung tissue. We stimulated lung explants with L. pneumophila strains and outer membrane vesicles (OMVs) to analyze tissue damage, bacterial replication, and localization as well as the transcriptional response of infected tissue. Interestingly, we found that extracellular adhesion of L. pneumophila to the entire alveolar lining precedes bacterial invasion and replication in recruited macrophages. In contrast, OMVs predominantly bound to alveolar macrophages. Specific damage to septa and epithelia increased over 48 h and was stronger in wild-type-infected and OMV-treated samples than in samples infected with the replication-deficient, type IVB secretion-deficient DotA − strain. Transcriptome analysis of lung tissue explants revealed a differential regulation of 2,499 genes after infection. The transcriptional response included the upregulation of uteroglobin and the downregulation of the macrophage receptor with collagenous structure (MARCO). Immunohistochemistry confirmed the downregulation of MARCO at sites of pathogen-induced tissue destruction. Neither host factor has ever been described in the context of L. pneumophila infections. This work demonstrates that the tissue explant model reproduces realistic features of Legionnaires' disease and reveals new functions for bacterial OMVs during infection. Our model allows us to characterize early steps of human infection which otherwise are not feasible for investigations.

Metastasis represents a major problem in the treatment of patients with advanced primary breast cancer. Both Transforming Growth Factor-Beta (TGF-β) signaling and Plasminogen Activator (PA) components, urokinase-type Plasminogen Activator (uPA) and Plasminogen Activator Inhibitor-1 (PAI-1) represent a complex network crucial for such enhanced invasiveness of tumors and imply high prognostic/predictive and promising therapeutic potential. Therefore, protein expression of specific effector molecules comprising the main parts of the TGF-β signaling pathway were determined in HOPE-fixed human tumor tissues through IHC (Scoring) using tissue microarray (TMA) technique and correlated with respective uPA and PAI-1 levels determined earlier in the same TMAs through optimized IHC and semi-quantitative image analysis. TGF-β signaling was active in vast majority (96 %) of the tumor samples and 88 % of all cases were significantly correlated with established metastasis markers uPA and PAI-1. In addition, TGF-β was also closely associated with tumor size, nodal status and two steroid hormone receptors. Consistent interrelationships between TGF-β, PA components and additional tumor characteristics underline the superiority of such more comprising data with regards to confirming TGF-β signaling as a promising target system to inhibit metastasis in advanced breast cancer.

Haptoglobin is a long known acute phase protein involved in hemoglobin breakdown, which was thought to be from the liver. The discovery of pHp was achieved by applying transcriptome analysis to human lung tissues which were subjected to a short term culture and infected or not infected with Haemophilus influenzae. These tissues were fixed and paraffin-embedded by the HOPE-technique. First, RT-PCR and RNA-in situ hybridization was used to confirm the pulmonary derivation of pHp. Immunohistochemistry was performed and showed expression of haptoglobin in Alveolar Epithelial Cells type II (AECII), macrophages (MA), and bronchial epithelia. Interestingly, pHp is expressed in adenocarcinomas but not in squamous cells carcinomas of the lungs; it even can be used as an additional diagnostic marker for routine purposes. In a large series of tissues we analyzed the regulation of pHp and its receptor CD163 and found an up-regulation in response to LPS, PAM3, Il6 and dexamethasone on the protein- and RNA-level. The analyses were carried out with lung tissues, A549 cells, and BALs. We found that pHp and CD 163 get rapidly secreted upon stimulation in comparably large amounts. Further experiments showed that pHp up-regulates Il8 and MCP-1 in A549 cells and TNF-α, Il6 and MCP-1 in monocyte derived macrophages, indicating a functional role in immuno-regulatory events in the human lung. pHp and its receptor act as native local pulmonary defense elements within the human respiratory system. Further studies are underway to elucidate the role of pHp in the course of different diseases of the lungs.

Background: Different therapy regimens in non-small-cell lung cancer (NSCLC) are of rising clinical importance, and therefore a clear-cut subdifferentiation is mandatory. The common immunohistochemical markers available today are well applicable for subdifferentiation, but a fraction of indistinct cases still remains, demanding upgrades of the panel by new markers. Methods: We report here the generation and evaluation of a new monoclonal antibody carrying the MAdL designation, which was raised against primary isolated human alveolar epithelial cells type 2. Results: Upon screening, one clone (MAdL) was identified as a marker for alveolar epithelial cell type II, alveolar macrophages and adenocarcinomas of the lung. In a large-scale study, this antibody, with an optimised staining procedure for formalin-fixed tissues, was then evaluated together with the established markers thyroid transcription factor-1, surfactant protein-A, pro-surfactant protein-B and napsin A in a series of 362 lung cancer specimens. The MAdL displays a high specificity (>99%) for adenocarcinomas of the lung, together with a sensitivity of 76.5%, and is capable of delivering independent additional diagnostic information to the established markers. Conclusion: We conclude that MAdL is a new specific marker for adenocarcinomas of the lung, which helps to clarify subdifferentiation in a considerable portion of NSCLCs.

Background Nontypeable Haemophilus influenzae (NTHI) may play a role as an infectious trigger in the pathogenesis of chronic obstructive pulmonary disease (COPD). Few data are available regarding the influence of acute and persistent infection on tissue remodelling and repair factors such as transforming growth factor (TGF)-β. Methods NTHI infection in lung tissues obtained from COPD patients and controls was studied in vivo and using an in vitro model. Infection experiments were performed with two different clinical isolates. Detection of NTHI was done using in situ hybridization (ISH) in unstimulated and in in vitro infected lung tissue. For characterization of TGF-β signaling molecules a transcriptome array was performed. Expression of the TGF-pseudoreceptor BMP and Activin Membrane-bound Inhibitor (BAMBI) was analyzed using immunohistochemistry (IHC), ISH and PCR. CXC chemokine ligand (CXCL)-8, tumor necrosis factor (TNF)-α and TGF-β expression were evaluated in lung tissue and cell culture using ELISA. Results In 38% of COPD patients infection with NTHI was detected in vivo in contrast to 0% of controls (p < 0.05). Transcriptome arrays showed no significant changes of TGF-β receptors 1 and 2 and Smad-3 expression, whereas a strong expression of BAMBI with upregulation after in vitro infection of COPD lung tissue was demonstrated. BAMBI was expressed ubiquitously on alveolar macrophages (AM) and to a lesser degree on alveolar epithelial cells (AEC). Measurement of cytokine concentrations in lung tissue supernatants revealed a decreased expression of TGF-β (p < 0.05) in combination with a strong proinflammatory response (p < 0.01). Conclusions We show for the first time the expression of the TGF pseudoreceptor BAMBI in the human lung, which is upregulated in response to NTHI infection in COPD lung tissue in vivo and in vitro. The combination of NTHI-mediated induction of proinflammatory cytokines and inhibition of TGF-β expression may influence inflammation induced tissue remodeling.