Tumor drugs are no longer limited to chemotherapy-based tumor killing, such as Alkylating agents (e.g., Mechlorethamine, Cyclophosphamide),25 but also include differentiation in angiogenesis inhibition (e.g., EGFR inhibitors like Lapatinib and Gefitinib and VEGFR inhibitors e.g., Sunitinib, Sorafenib),25 tumor metabolism regulation (e.g., IDO1 inhibitors, IDH1 and IDH2 inhibitors),26 and restoration of self-immunity (e.g., anti-CD20 antibodies (rituximab and obinutuzumab).27 The combination of various drugs makes tumor therapy more precise and effective. Here, IDO1 is linked to neoplasm.