Immune Cell Metabolism and Immuno-Oncology

With the significant successes of immune checkpoint blockade and adoptive cellular therapy, immunotherapy has now become an established treatment option to effectively treat cancer. However, the full potential of this treatment modality has yet to be realized, as there are many additional mechanisms whereby tumors continue to evade immune destruction. To this end, metabolic reprogramming by cancer cells serves not only to promote their own growth but also to create an immunosuppressive tumor microenvironment. The tumor metabolic microenvironment not only inhibits antitumor effector function but also supports the differentiation and function of suppressive immune cells. In this review, we delineate the major metabolic programs of cancer cells and immune cells. Furthermore, we discuss the role of so-called metabolic checkpoints that promote immune evasion and tumor growth. Finally, we review current and potential future strategies to target metabolism in order to not simply inhibit tumor growth but also enhance antitumor immune responses. Such strategies have the great potential to enhance the breadth and depth of immunotherapy for cancer by targeting metabolic checkpoints.