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The pivotal role of neutrophils and macrophages in smoking-related lung inflammation and COPD development is well-established. We aimed to assess whether sputum concentrations of Human Neutrophil Peptides (HNP), Neutrophil Elastase (NE), Interleukin-8 (IL-8), and Metalloproteinase-9 (MMP-9), major products of neutrophils and macrophages, could be used to trace airway inflammation and progression towards pulmonary functional impairment characteristic of COPD. Forty-two symptomatic smokers and 42 COPD patients underwent pulmonary function tests; sputum samples were collected at enrolment, and 6 months after smoking cessation. HNP, NE, IL-8, MMP-9 levels were increased in individuals with COPD (p < 0.0001). HNP and NE concentrations were higher in patients with severe airways obstruction, as compared to patients with mild-to-moderate COPD (p =0.002). A negative correlation was observed between FEV&#95;{1} and HNP, NE and IL-8 levels (p < 0.01), between FEV&#95;{1}/FVC and HNP, NE and IL-8 levels (p< 0.01), and between NE enrolment levels and FEV&#95;{1} decline after 2 years (p =0.04). ROC analysis, to discriminate symptomatic smokers and COPD patients, showed the following AUCs: for HNP 0.92; for NE 0.81; for IL-8 0.89; for MMP-9 0.81; for HNP, IL-8 and MMP-9 considered together 0.981. The data suggest that the measurement of sputum markers may have an important role in clinical practice for monitoring COPD.

The level of activity of O6-alkylguanine-DNA-alkyltransferase (AGT), a DNA repair enzyme, in blood lymphocytes may be a marker of susceptibility to lung cancer. We measured the AGT activity level, expressed as pmoles of repaired bases/mg protein, in leukocytes of 153 lung cancer cases (of whom 80 were never smokers) and 106 controls (76 never smokers) enrolled in eight centres from seven countries. Subjects were interviewed with respect to active smoking and exposure to environmental tobacco smoke (ETS). Among never smokers, the odds ratios (ORs) of lung cancer were 1.3 (95% confidence interval 0.5-3.9), 1.5 (0.6-4.1) and 1.4 (0.5-3.8) in quartiles of decreasing AGT activity level, as compared to the upper quartile (P value of test for linear trend 0.6). Corresponding ORs among smokers were 3.4 (0.9-13), 2.0 (0.5-8.3) and 0.4 (0.1-1.6) (P value of test for linear trend 0.4). No interaction was suggested between AGT activity level and either cumulative smoking or exposure to ETS. Reduced AGT activity was not clearly associated with increased lung cancer risk in either smokers or non-smokers. However, the small size of our study argues for a prudent interpretation of our results.

The level of activity of O6-alkylguanine-DNA-alkyltransferase (AGT), a DNA repair enzyme, in blood lymphocytes may be a marker of susceptibility to lung cancer. We measured the AGT activity level, expressed as pmoles of repaired bases/mg protein, in leukocytes of 153 lung cancer cases (of whom 80 were never smokers) and 106 controls (76 never smokers) enrolled in eight centres from seven countries. Subjects were interviewed with respect to active smoking and exposure to environmental tobacco smoke (ETS). Among never smokers, the odds ratios (ORs) of lung cancer were 1.3 (95% confidence interval 0.5–3.9), 1.5 (0.6–4.1) and 1.4 (0.5–3.8) in quartiles of decreasing AGT activity level, as compared to the upper quartile (P value of test for linear trend 0.6). Corresponding ORs among smokers were 3.4 (0.9–13), 2.0 (0.5–8.3) and 0.4 (0.1–1.6) (P value of test for linear trend 0.4). No interaction was suggested between AGT activity level and either cumulative smoking or exposure to ETS. Reduced AGT activity was not clearly associated with increased lung cancer risk in either smokers or non-smokers. However, the small size of our study argues for a prudent interpretation of our results. [Copyright &y& Elsevier]