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Amir Soltani,1 Eugene Haydn Walters,1,* David W Reid,1,2 Shakti Dhar Shukla,1 Kaosia Nowrin,1 Chris Ward,3 H Konrad Muller,1 Sukhwinder Singh Sohal1,4,* 1NHMRC Center of Research Excellence for Chronic Respiratory Disease, School of Medicine, University of Tasmania, Hobart, TAS, Australia; 2Iron Metabolism Laboratory, Queensland Institute of Medical Research, Brisbane, QLD, Australia; 3Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, Tyne and Wear, UK; 4School of Health Sciences, University of Tasmania, Launceston, TAS, Australia *These authors contributed equally to this work Background: This study assessed the effects of inhaled corticosteroid (ICS) on airway vascular remodeling in chronic obstructive pulmonary disease (COPD). Methods: Thirty-four subjects with mild-to-moderate COPD were randomly allocated 2:1 to ICS or placebo treatment in a double-blinded clinical trial over 6 months. Available tissue was compared before and after treatment for vessel density, and expression of VEGF, TGF-β1, and TGF-β1-related phosphorylated transcription factors p-SMAD 2/3. This clinical trial has been registered and allocated with the Australian New Zealand Clinical Trials Registry (ANZCTR) on 17/10/2012 with reference number ACTRN12612001111864. Results: There were no significant baseline differences between treatment groups. With ICS, vessels and angiogenic factors did not change in hypervascular reticular basement membrane, but in the hypovascular lamina propria (LP), vessels increased and this had a proportionate effect on lung air trapping. There was modest evidence for a reduction in LP vessels staining for VEGF with ICS treatment, but a marked and significant reduction in p-SMAD 2/3 expression. Conclusion: Six-month high-dose ICS treatment had little effect on hypervascularity or angiogenic growth factors in the reticular basement membrane in COPD, but normalized hypovascularity in the LP, and this was physiologically relevant, though accompanied by a paradoxical reduction in growth factor expression. Keywords: airway remodeling, bronchial biopsy, COPD, inhaled corticosteroid, vascular remodeling

Malik Quasir Mahmood,1,* Sukhwinder Singh Sohal,1,2,* Shakti Dhar Shukla,1 Chris Ward,3 Ashutosh Hardikar,4 Wan Danial Noor,1 Hans Konrad Muller,1 Darryl A Knight,5 Eugene Haydn Walters1 1NHMRC Centre of Research Excellence for Chronic Respiratory Disease and Lung Ageing, School of Medicine, University of Tasmania, Hobart, TAS, Australia; 2School of Health Sciences, Faculty of Health, University of Tasmania, Launceston, TAS, Australia; 3Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, Tyne and Wear, UK; 4Royal Hobart Hospital, Hobart, TAS, Australia; 5School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, NSW, Australia *These authors contributed equally to this work Background: Small airway fibrosis is the main contributor in airflow obstruction in chronic obstructive pulmonary disease. Epithelial mesenchymal transition (EMT) has been implicated in this process, and in large airways, is associated with angiogenesis, ie, Type-3, which is classically promalignant. Objective: In this study we have investigated whether EMT biomarkers are expressed in small airways compared to large airways in subjects with chronic airflow limitation (CAL) and what type of EMT is present on the basis of vascularity. Methods: We evaluated epithelial activation, reticular basement membrane fragmentation (core structural EMT marker) and EMT-related mesenchymal biomarkers in small and large airways from resected lung tissue from 18 lung cancer patients with CAL and 9 normal controls. Tissues were immunostained for epidermal growth factor receptor (EGFR; epithelial activation marker), vimentin (mesenchymal marker), and S100A4 (fibroblast epitope). Type-IV collagen was stained to demonstrate vessels. Results: There was increased expression of EMT-related markers in CAL small airways compared to controls: EGFR (P

Shakti Dhar Shukla,1,* Sukhwinder Singh Sohal,1,* Malik Quasir Mahmood,1 David Reid,2 Hans Konrad Muller,1 Eugene Haydn Walters1 1NHMRC Centre for Research Excellence for Chronic Respiratory Disease and Lung Ageing, School of Medicine, University of Tasmania, Hobart, Tasmania, Australia; 2Queensland Institute of Medical Research, Iron Metabolism Laboratory, Brisbane, Queensland, Australia *Shakti Dhar Shukla and Sukhwinder Singh Sohal are joint first authors Background: We recently published that platelet-activating factor receptor (PAFr) is upregulated on the epithelium of the proximal airways of current smokers and also in bronchial epithelial cells exposed to cigarette smoke extract. These treated cells also showed upregulation of Streptococcus pneumoniae adhesion. Bacterial wall phosphorylcholine specifically binds to PAFr expressed on airway epithelium, thus facilitating adherence and tissue invasion, which may be relevant to chronic obstructive pulmonary disease (COPD). Moreover, the use of inhaled corticosteroids (ICS) in COPD patients is associated with an increased risk of invasive respiratory pneumococcal infections. Objective: In this study, we have investigated whether PAFr expression is especially upregulated in airway epithelium in COPD patients and whether this expression may be modulated by ICS therapy. Methods: We cross-sectionally evaluated PAFr expression in bronchial biopsies from 15 COPD patients who were current smokers (COPD-smokers) and 12 COPD-ex-smokers, and we compared these to biopsies from 16 smokers with normal lung function. We assessed immunostaining with anti-PAFr monoclonal antibody. We also used material from a previous double-blinded randomized placebo-controlled 6-month ICS intervention study in COPD patients to explore the effect of ICS on PAFr expression. We employed computer-aided image analysis to quantify the percentage of epithelium stained for PAFr. Results: Markedly enhanced expression of PAFr was found in both COPD-smokers (P

Sukhwinder Singh Sohal,1,* Amir Soltani,1,* David Reid,1,2 Chris Ward,1,3 Karen E Wills,1,4 H Konrad Muller,1 Eugene Haydn Walters1 1National Health and Medical Research Council Centre of Research Excellence for Chronic Respiratory Disease, School of Medicine, University of Tasmania, Hobart, Tasmania, Australia; 2Iron Metabolism Laboratory, Queensland Institute of Medical Research, Brisbane, Queensland, Australia; 3Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, Tyne and Wear, UK; 4Department of Biostatistics, Menzies Research Institute Tasmania, University of Tasmania, Hobart, Tasmania, Australia *These authors contributed equally to this workBackground: We recently reported that epithelial–mesenchymal transition (EMT) is active in the airways in chronic obstructive pulmonary disease (COPD), suggesting presence of an active profibrotic and promalignant stroma. With no data available on potential treatment effects, we undertook a blinded analysis of inhaled corticosteroids (ICS) effects versus placebo on EMT markers in previously obtained endobronchial biopsies in COPD patients, as a “proof of concept” study.Methods: Assessment of the effects of inhaled fluticasone propionate (FP; 500 µg twice daily for 6 months) versus placebo in 34 COPD patients (23 on fluticasone propionate and eleven on placebo). The end points were epidermal growth factor receptor (EGFR; marker of epithelial activation) and the biomarkers of EMT: reticular basement membrane (Rbm) fragmentation (“hallmark” structural marker), matrix metalloproteinase-9 (MMP-9) cell expression, and S100A4 expression in basal epithelial and Rbm cells (mesenchymal transition markers).Results: Epithelial activation, “clefts/fragmentation” in the Rbm, and changes in the other biomarkers all regressed on ICS, at or close to conventional levels of statistical significance. From these data, we have been able to nominate primary and secondary end points and develop power calculations that would be applicable to a definitive prospective study.Conclusion: Although only a pilot “proof of concept” study, this trial provided strong suggestive support for an anti-EMT effect of ICS in COPD airways. A larger and fully powered prospective study is now indicated as this issue is likely to be extremely important. Such studies may clarify the links between ICS use and better clinical outcomes and protection against lung cancer in COPD.Keywords: pilot trial, reticular basement membrane, S100A4, EGFR, MMP-9, lung cancer