Research on the Metabolism of Immune Cells and Immune Escape Mechanisms in the Tumor Immune Microenvironment

Abstract

The tumor microenvironment (TME) is a complex and dynamic system consisting of tumor cells, immune cells, stromal cells, and extracellular matrix, whose internal metabolic state and other characteristics have a profound impact on the proliferation, invasion, metastasis and treatment response of tumors. Currently, there is a problem of poor treatment efficiency for tumors due to immune escape. So, analyzing the internal relationship between the metabolism of immune cells and the mechanism of immune escape in TME is a goal for improving treatment outcomes. This study involved analyzing the changes in immune cell metabolites and investigating the impact of metabolic pathways on immune function. Firstly, the metabolic changes of different immune cells (CD8⁺T cells, NK cells, Tregs, TAMs) were described, and it was found there was a significant metabolic disorder in TME. The reprogramming of sugar metabolism inhibits immune activity, the fatty acid metabolism promotes immune evasion, and the disorder of amino acid metabolism seizes key amino acids leading to the immune cells being in a “nutritional deficiency” state. Meanwhile, the abnormal accumulation of metabolites such as lactic acid and ketone bodies jointly creates an immunosuppressive microenvironment. However, some immune functions can be restored and the growth of tumors can be inhibited by regulating certain metabolic pathways. Treating the metabolic disorders in TME is expected to become a breakthrough in tumor immune suppression. It provides experimental evidence for developing the combined strategy of “metabolic regulation + immunotherapy” and opens up a new direction for the design of tumor treatment plans.