Smoking history influences the prognostic value of peripheral naive CD4+T cells in advanced non-small cell lung cancer

BackgroundConsidering the effect of smoking on tumor immunity, we attempted to investigate the impact of smoking history on the prognostic value of circulating naive and memory CD4+ and CD8+ T cells in advanced non-small cell lung cancer (NSCLC) treated with chemo(radio)therapy.MethodsOf 196 histologically confirmed advanced NSCLC, 98 eligible ones were enrolled. Naive and memory CD4+ and CD8+ T cells from peripheral blood were measured by flow cytometry. Kaplan-Meier curves helped estimate patients' survival. The uni- and multivariate Cox proportional hazards regression model was employed in the assessment of the prognostic value of factors.ResultsMultivariate survival analyses showed that peripheral naive CD4+ T cells independently predicted favorable overall survival (OS) in ever smokers with advanced NSCLC (P=0.007), but unfavorable OS in never smokers with the same ailment (P=0.012). Ever smokers presented a different distribution of naive and memory T cells: low expression levels of naive CD4+ T (P=0.005), naive CD8+ T (P=0.031), CD4+ naive/memory ratio (P=0.020), and CD8+ naive/memory ratio (P=0.019), and high distributions of memory CD4+T (P=0.004), memory CD8+T (P=0.034), and naive CD8/CD4 ratio (P=0.020), when compared to never smokers.ConclusionsWe revealed the impact of cigarette-smoking on peripheral naive CD4+ T cells' prognostic value in advanced NSCLC patients. These results could help in refining personalized treatment for advanced NSCLC patients.