Furthermore, Bessode et al. demonstrated that the accumulation of the tryptophan catabolizing enzyme indoleamine 2,3-dioxygenase 1 (IDO1) within non-small cell lung cancer (NSCLC) induces an immunosuppressive state by converting tryptophan into various immunosuppressive metabolites, such as L-kynurenine 60. The gene discussed is IDO1; the disease is non-small cell lung carcinoma.