RT Journal Article SR Electronic T1 Deciphering the link between COPD and lung cancer: Cigarette smoke-induced immunosuppression at the crossroads between cancer immune surveillance and escape JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP PA1898 DO 10.1183/13993003.congress-2015.PA1898 VO 46 IS suppl 59 A1 Dimitra Kerdidani A1 Konstantinos Glynos A1 Sophia Magkouta A1 Giorgos Kazamias A1 Vassiliki Karavana A1 Charis Roussos A1 Dimitra Rontogianni A1 Ioannis Kalomenidis A1 Spyros Zakynthinos A1 Maria Tsoumakidou YR 2015 UL http://erj.ersjournals.com/content/46/suppl_59/PA1898.abstract AB Introduction: COPD increases the incidence of lung cancer independently of cigarette smoking. A hallmark of cancer is its remarkable ability to evade immunity. Cigarette smoke (CS) exposure has been associated with suppressed T cell immunity against pathogens. T cells are the frontline of defense against tumors. AIMS. To establish an orthotopic model of lung cancer in fully immunocompetent mice and investigate whether CS suppresses anti-tumor T cell responses.Methods: C57BL/6J wild type mice were either exposed to CS or sham. On day 30 syngeneic Lewis Lung Cancer (LLC) cells (or cancer-free media) were inoculated on the left lung lobe. On day 40 animals were sacrificed. Intratumoral and draining lymph node T cells were analyzed by 8-colour flow-cytometry.Results: A higher number of T helper and T cytotoxic (Tc) was observed in the lungs and draining lymph nodes of both CS-exposed and sham-exposed mice after inoculation of lung cancer cells compared to cancer free media, showing that cancer cell inoculation triggers adaptive immune responses in our mice models. However, intratumoral and lymph node T cells of CS-exposed mice with cancer showed a less activated/cytotoxic phenotype and produced higher levels of the inhibitory molecules TIM3, CTLA4, CD39, CD73 and of the immunosuppressive cytokine IL-10 than those of sham-exposed mice with cancer.Conclusions: Short-term CS-exposure suppresses early anti-tumor T cell responses in vivo. Impaired anti-cancer specific immunity in smokers could be a critical determinant of lung cancer escape from immunesurveillance mechanisms.