HCC eludes the anti-tumour immunity by fostering an intricate network of immunosuppression pathways involving tumour and stromal cells by instigating a response opposing the priming of T cells and immune effector functions through the secretion of multitude immunosuppressive cytokines such as IL-10, IFN-γ, TGF-β, IDO, and so on [18]. The gene discussed is IDO1; the disease is hepatocellular carcinoma.