title: Expansion of myeloid-derived suppressor cells in chronic obstructive pulmonary disease and lung cancer: potential link between inflammation and cancer.
abstract: BACKGROUND
  Chronic obstructive pulmonary disease (COPD) is a risk factor for lung cancer (LC). Myeloid-derived suppressor cells (MDSCs) down-regulate the T cell receptor ζ chain (TCR ζ) through L-arginine deprivation and lead to T cell dysfunction and deficient antitumor immunity. We hypothesized that abnormally high levels of MDSCs in COPD patients may alter tumor immunosurveillance.
  
  
  METHODS
  We compared the proportion of circulating MDSCs (Lin-HLA-DR-/CD33+/CD11b+) (by flow cytometry), arginase I (ARG I) serum levels (by ELISA), and expression levels of TCR ζ on circulating lymphocytes (by flow cytometry) in 28 patients with LC, 62 subjects with COPD, 41 patients with both LC and COPD, 40 smokers with normal spirometry and 33 non-smoking controls. T cell proliferation assays were performed in a subgroup of participants (CFSE dilution protocol).
  
  
  RESULTS
  We found that: (1) circulating MDSCs were up-regulated in COPD and LC patients (with and without COPD); (2) MDSCs expansion was associated with TCR ζ down-regulation in the three groups; (3) in LC patients, these findings were independent of COPD and tobacco smoking exposure; (4) TCR ζ down-regulation correlates with T cell hyporesponsiveness in COPD and LC patients.
  
  
  CONCLUSIONS
  These results suggest that tumor immunosurveillance might be impaired in COPD and may contribute to the increased risk of LC reported in these patients.
authors.affiliation: Instituto de Investigación Sanitaria de Palma, (IdISPa), Hospital Universitari Son Espases, C/Valldemossa 79, Planta 0, Mod. C, 07010, Palma de Mallorca, Spain.
authors.forename: Sergio
authors.initials: S
authors.lastname: Scrimini
authors.forename: Jaume
authors.initials: J
authors.lastname: Pons
authors.forename: Alvar
authors.initials: A
authors.lastname: Agustí
authors.forename: Antonio
authors.initials: A
authors.lastname: Clemente
authors.forename: Marta Crespí
authors.initials: MC
authors.lastname: Sallán
authors.forename: Josep Miquel
authors.initials: JM
authors.lastname: Bauçà
authors.forename: Joan B
authors.initials: JB
authors.lastname: Soriano
authors.forename: Borja G
authors.initials: BG
authors.lastname: Cosio
authors.forename: Meritxel
authors.initials: M
authors.lastname: Lopez
authors.forename: Catalina
authors.initials: C
authors.lastname: Crespi
authors.forename: Jaume
authors.initials: J
authors.lastname: Sauleda
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001119:Arginase / Q000097:blood; D002283:Carcinoma, Bronchogenic / Q000276:immunology* / Q000473:pathology; D049109:Cell Proliferation; D002478:Cells, Cultured; D005260:Female; D006801:Humans; D007249:Inflammation / Q000276:immunology; D008175:Lung Neoplasms / Q000276:immunology* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D015166:Monitoring, Immunologic; D022423:Myeloid Cells / Q000276:immunology*; D009367:Neoplasm Staging; D029424:Pulmonary Disease, Chronic Obstructive / Q000276:immunology* / Q000473:pathology; D011948:Receptors, Antigen, T-Cell / Q000378:metabolism; D012907:Smoking / Q000009:adverse effects; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D011948:Receptors, Antigen, T-Cell; C054979:antigen T cell receptor, zeta chain; D001119:Arginase