Immune Checkpoints in COPD

The aim of this study is to investigate the mechanisms underlying the complex interaction between Chronic obstructive pulmonary disease (COPD) and lung cancer. Therefore, in order to identify a possible role of immune checkpoints not only in the susceptibility to COPD development but also in its evolution towards lung cancer, will be evaluate the correlation between PD-L1 expression and cigarette smoke exposure in COPD patients. Although there are many epidemiological studies highlighting the interconnections between COPD and lung cancer and the influence of cigarette smoke, the molecular bases of this association are less well defined. Initially they were thought to be driven just by innate inflammation, however, recent studies have also demonstrated the influence of the adaptive immune system. Despite this, the role of immune checkpoints in chronic lung inflammatory diseases such as COPD is less well understood. COPD is currently the 4th leading cause of death worldwide but is assessed to be the 3rd by the end of 2020 resulting in an economic and social burden that is in continuous progression. Patients will be recruited from from the outpatient clinics of the Pulmonary and Critical Care Medicine department of "Mauro Scarlato" Hospital in Scafati, Italy in collaboration with the Operational Unit of Clinical Pharmacology and Pharmacovigilance of Catanzaro University. 171 patients will be divided according to the results of the anatomopathological examinations into four groups: * Healthy never smokers * Smokers with normal lung * Cancer * COPD (COPD group was divided in two subgroups: GOLD 1-2 group and GOLD 3-4 group).