title: Relationships between chronic obstructive pulmonary disease and lung cancer: biological insights.
abstract: Lung cancer (LC) has become one of the leading causes of preventable death in the last few decades. Cigarette smoking (CS) stays as the main etiologic factor of LC despite that many other causes such as occupational exposures, air pollution, asbestos, or radiation have also been implicated. Patients with chronic obstructive pulmonary disease (COPD), which also represents a major cause of morbidity and mortality in developed countries, exhibit a significantly greater risk of LC. The study of the underlying biological mechanisms that may predispose patients with chronic respiratory diseases to a higher incidence of LC has also gained much attention in the last few years. The present review has been divided into three major sections in which different aspects have been addressed: (I) relevant etiologic agents of LC; (II) studies confirming the hypothesis that COPD patients are exposed to a greater risk of developing LC; and (III) evidence on the most relevant underlying biological mechanisms that support the links between COPD and LC. Several carcinogenic agents have been described in the last decades but CS remains to be the leading etiologic agent in most geographical regions in which the incidence of LC is very high. Growing evidence has put the line forward the implications of COPD and especially of emphysema in LC development. Hence, COPD represents a major risk factor of LC in patients. Different avenues of research have demonstrated the presence of relevant biological mechanisms that may predispose COPD patients to develop LC. Importantly, the so far identified biological mechanisms offer targets for the design of specific therapeutic strategies that will further the current treatment options for patients with LC. Prospective screening studies, in which patients with COPD should be followed up for several years will help identify biomarkers that may predict the risk of LC among these patients.
authors.affiliation: Pulmonology Department-Lung Cancer and Muscle Research Group, IMIM-Hospital del Mar, Parc de Salut Mar, Health and Experimental Sciences Department (CEXS), Pompeu Fabra University (UPF), Barcelona Autonomous University (UAB), Barcelona Biomedical Research Park (PRBB), Barcelona, Spain; ; Network of Excellence in Lung Diseases (CIBERES), Carlos III Health Institute (ISCIII), Madrid, Spain.
authors.forename: Esther
authors.initials: E
authors.lastname: Barreiro
authors.affiliation: Pneumology Department, Basurto University Hospital, Osakidetza, Department of Medicine, EHU-University of the Basque Country, Bilbao, Bizkaia, Spain.
authors.forename: Víctor
authors.initials: V
authors.lastname: Bustamante
authors.affiliation: Pulmonology Department-Lung Cancer and Muscle Research Group, IMIM-Hospital del Mar, Parc de Salut Mar, Health and Experimental Sciences Department (CEXS), Pompeu Fabra University (UPF), Barcelona Autonomous University (UAB), Barcelona Biomedical Research Park (PRBB), Barcelona, Spain; ; Network of Excellence in Lung Diseases (CIBERES), Carlos III Health Institute (ISCIII), Madrid, Spain.
authors.forename: Víctor
authors.initials: V
authors.lastname: Curull
authors.affiliation: Pulmonology Department-Lung Cancer and Muscle Research Group, IMIM-Hospital del Mar, Parc de Salut Mar, Health and Experimental Sciences Department (CEXS), Pompeu Fabra University (UPF), Barcelona Autonomous University (UAB), Barcelona Biomedical Research Park (PRBB), Barcelona, Spain; ; Network of Excellence in Lung Diseases (CIBERES), Carlos III Health Institute (ISCIII), Madrid, Spain.
authors.forename: Joaquim
authors.initials: J
authors.lastname: Gea
authors.affiliation: Network of Excellence in Lung Diseases (CIBERES), Carlos III Health Institute (ISCIII), Madrid, Spain; ; Medical-Surgery Unit of Respiratory Disease, Sevilla Biomedicine Institute (IBIS), Virgen del Rocío University Hospital, University of Seville, Seville, Spain.
authors.forename: José Luis
authors.initials: JL
authors.lastname: López-Campos
authors.affiliation: Network of Excellence in Lung Diseases (CIBERES), Carlos III Health Institute (ISCIII), Madrid, Spain; ; Pulmonology Service, Medicine Department, Vall d'Hebron University Hospital, Barcelona Autonomous University (UAB), Barcelona, Spain.
authors.forename: Xavier
authors.initials: X
authors.lastname: Muñoz
keywords: Chronic obstructive pulmonary disease (COPD); epidemics; etiologic agents; lung cancer (LC); underlying biological mechanisms