Immunometabolism in Cancer: Targeting Metabolic Pathways to Enhance Immune Responses

Cancer cell metabolism and immune cell functions have complex interconnections. This review discusses emerging metabolic targets which have the potential to improve immune cell functions. The tumor microenvironment (TME) presents unique metabolic attributes such as nutrient competition, hypoxia, and buildup of immunosuppressive metabolites. These components collectively impair anti-tumor immune responses. Novel therapeutic approaches targeting key metabolic pathways, including glutamine metabolism, adenosine signaling, fatty acid oxidation, and amino acid metabolism have shown potential in improving immunity. For example, glutamine antagonists have demonstrated reprograming of tumor-associated macrophages and enhanced T cell responses. Also, adenosine pathway inhibitors have exhibited synergism with existing immunotherapies. Further, strategies like mitochondrial transfer resulted in rejuvenation of exhausted T cells. Integration of metabolic inhibitors with conventional immunotherapies, such as glutaminase inhibitors with immune checkpoint blockade, have displayed synergistic effects. Notwithstanding the advantages many challenges, like metabolic plasticity, tumor heterogeneity, and poor drug delivery, remain to be overcome. Approaches including development of specific metabolic inhibitors, identification of reliable biomarkers, and implementation of adaptive treatment strategies with the help artificial intelligence are also discussed. This review highlights the potential of immunometabolic interventions in cancer treatment while acknowledging the complexity of targeting cellular metabolism.