The competition of amino acid among tumors, tumor-associated macrophages and T cells based on metabolic reprogramming.

Amino acids are important nutrients in the process of tumor proliferation. Dysregulated amino acid metabolism profoundly influences tumor growth and immune cell function. Within the tumor microenvironment (TME), metabolic reprogramming of amino acids modulates the polarization of tumor-associated macrophages (TAMs) and the differentiation of T cells, processes intimately linked to tumor immune evasion. Meanwhile, metabolic reprogramming leads to amino acid competition between tumor cells and immune cells, particularly TAMs and T cells. To meet their own amino acid needs, tumors carry out a series of optimized metabolic strategies by expressing specific enzymes, cytokines, and amino acid transporters, and so forth promoting the formation of an immunosuppressive microenvironment and hindering anti-tumor immunity. Notably, this metabolic competition may exhibit spatial heterogeneity and temporal dynamics. Given the central role of amino acid metabolism in tumor progression and immune evasion, targeting key metabolic pathways represents a promising therapeutic strategy for cancer treatment.