Figure 3.

The metabolism targets for immunotherapy. (A) Targeting PD-1 and CTLA-4 to restore the immune function of T cells. (B) The lactic acid generated by glycolysis in tumor cells is transported outside the tumor cells through monocarboxylate transporter 1 (MCT1). Besides, lactic acid accumulation may inhibit the function of T effector cells and promote the function of M2-like TAMs, Treg cells, and MDSC. (C) CD36 is a glycoprotein that can help fatty acids pass through the cell membrane. Increased expression of CD36 enhances the fatty acid oxidation in M2like TAMs, eventually leading to immunosuppression. Therefore, CD36 inhibitors can hinder the intake of fatty acids by M2-like TAMs and ultimately achieve the purpose of inhibiting tumor progression. (D) IDO, produced by Tregs, decomposes tryptophan to specific metabolites, inhibiting the function of immune cells, such as effector T cells. Targeting IDO can inhibit tumor development by restoring tumor immunity. Created with "BioRender.com".