Likewise, Li et al. (2018) and Sui et al. (2020) analyzed the microenvironmental differences between smokers and non-smokers with lung adenocarcinomas, and found relatively high proportions of CD8+ T cells, activated CD4+ T cells, and M1 macrophages in smokers with lung adenocarcinomas (Kinoshita et al., 2016). The gene discussed is CD8A; the disease is lung adenocarcinoma.