In contrast, when T-cells derived from individuals with lung carcinoma and those undergoing stress were treated with dopamine, it significantly inhibited the proliferation of human CD4+ and CD8+ T-cells and significantly reduced CD8+ T-cell cytotoxicity through D1-mediated cAMP signaling (Saha, Mondal, Basu et al., 2001, Saha, Mondal, Majumder et al., 2001). This evidence concerns the gene CD8A and lung carcinoma.