Study Design and Interim Outcomes of Guangzhou Institute of Respiratory Disease COPD Biobank.

BACKGROUND: GIRD COPD Biobank is a multicenter observational study blood-based database with local characteristics, in order to investigate the causes, risk factors, pathogenesis, prevalence patterns and trends of COPD and promote new pathogenic insights in China. METHODS: We enrolled 855 clinically COPD patients and 660 controls with normal lung function. Extensive data collection has been undertaken with questionnaires, clinical measurements, and collection and storage of blood specimens, following Standard Operating Procedures (SOP). All surveys had similar quality controls, supervisions, and training of the investigator team. RESULTS: Since September 2010, a total of 1515 subjects (1116 [73.7%] males; 855 [56.4%] diagnosed with COPD) were enrolled. Analyses of the design and interim results of the GIRD COPD Biobank Study identified patients with COPD were older, lower educational level, a longer history of pack-year smoking, less in kitchen fan usage, X-ray exposure, and history of disease (P < 0.01 for all); Most of the COPD subjects belonged to moderately severe or worse, stratified according to Global Lung Function Initiative (GLI); COPD patients had relatively more co-morbidities than controls; Environmental hazard exposures might be the main contributors to the reported respiratory symptoms; Cold air, haze, and influenza acted the top three factors to induce respiratory symptoms in both COPD cases and controls. CONCLUSION: The GIRD COPD Biobank Study has the potential to provide substantial novel insights into the genetics, biomarkers, environmental and lifestyle aspects of COPD. It is expected to provide new insights for pathogenesis and the long-term progression of COPD.

Bone morphogenetic protein 4 inhibits liposaccharide-induced inflammation in the airway.

Bone morphogenetic protein 4 (BMP4) is a multifunctional growth factor that belongs to the TGF-ß superfamily. The role of BMP4 in lung diseases is not fully understood. Here, we demonstrate that BMP4 was upregulated in lungs undergoing lipopolysaccharide (LPS)-induced inflammation, and in airway epithelial cells treated with LPS or TNF-α. BMP4 mutant (BMP4(+/-) ) mice presented with more severe lung inflammation in response to LPS or Pseudomonas aeruginosa, and lower bacterial load compared with that in BMP4(+/+) mice. Knockdown of BMP4 by siRNA increased LPS and TNF-α-induced IL-8 expression in 16HBE human airway epithelial cells and in primary human bronchial epithelial cells. Similarly, peritoneal macrophages from BMP4(+/-) mice produced greater levels of TNF-α and keratinocyte chemoattractant (KC) upon LPS treatment compared with cells from BMP4(+/+) mice. Administration of exogenous BMP4 attenuated the upregulation of TNF-α, IL-8, or KC induced by LPS and/or TNF-α in airway epithelial cells, and peritoneal macrophages. Finally, partial deficiency of BMP4 in BMP4(+/-) mice protected the animals from restrictive lung function reduction upon chronic LPS exposure. These results indicate that BMP4 plays an important anti-inflammatory role, controlling the strength and facilitating the resolution of acute lung inflammation; yet, BMP4 also contributes to lung function impairment during chronic lung inflammation.

Nicotine enhances store­operated calcium entry by upregulating HIF­1α and SOCC components in non­small cell lung cancer cells.

Store­operated calcium entry (SOCE) is critical for regulating the proliferation and metastasis of various cancer types. The present study aimed to investigate the role of SOCE on nicotine­promoted proliferation of non­small cell lung cancer (NSCLC) A549 cells. Cell proliferation was evaluated by BrdU incorporation assay. The SOCE and basal [Ca2+]i in NSCLC A549 cells were determined using Fura­2 fluorescence microscopy. The mRNA and protein expression levels were determined by real­time quantitative PCR and western blotting, respectively. The results demonstrated that, in A549 cells, the detectable store­operated calcium channel (SOCC) components were TRPC proteins 1, 3, 4 and 6 and Orail, among which TRPC1, TRPC6 and Orai1 are expressed at relatively high levels with TRPC3 and TRPC4 at relatively low levels. Nicotine upregulated the mRNA and protein expression of TRPC1, TRPC6 and Orai1, increased basal [Ca2+]i and enhanced SOCE. Promotion of cell proliferation but not migration was observed in the nicotine­treated cells, which was inhibited by SOCE inhibitor SKF­96365. Furthermore, nicotine upregulated HIF­1α expression in the A549 and NCI­H292 cells. Silencing of HIF­1α abrogated the increases in TRPCs and Orail and reversed the increases in basal [Ca2+]i and SOCE. Meanwhile, suppression of proliferation was observed in cells following HIF­1α silencing. In conclusion, the results indicate that nicotine promotes lung cancer cell proliferation likely by upregulating HIF­1α and SOCC components and therefore enhancing SOCE and increasing basal [Ca2+]i.

Orai1, 2, 3 and STIM1 promote store-operated calcium entry in pulmonary arterial smooth muscle cells.

Previous studies have demonstrated that besides the classic canonical transient receptor potential channel family, Orai family and stromal interaction molecule 1 (STIM1) might also be involved in the regulation of store-operated calcium channels (SOCCs). An increase in cytosolic free Ca2+ concentration promoted by store-operated Ca2+ entry (SOCE) in pulmonary arterial smooth muscle cells (PASMCs) is a major trigger for pulmonary vasoconstriction and proliferation and migration of PASMCs. In this study, our data revealed the following: (1) in both rat distal pulmonary arteries and PASMCs, chronic hypoxia exposure upregulated the expression of Orai1 and Orai2, without affecting Orai3 and STIM1; (2) either heterozygous knockout of HIF-1α in mice or knockdown of HIF-1α in PASMCs abolished the hypoxic upregulation of Orai2, but not Orai1, suggesting the hypoxic upregulation of Orai2 depends on HIF-1α; and (3) using small interference RNA knockdown strategies, Orai1, 2, 3 and STIM1 were all shown to mediate SOCE in hypoxic PASMCs. Together, these results suggested that the components of SOCCs, including Orai1, 2, 3 and STIM1, may lead to novel therapeutic targets for the treatment of chronic hypoxia-induced pulmonary hypertension.