The XOR-IDH3α axis controls macrophage polarization in hepatocellular carcinoma

BACKGROUND & AIMS: Tumor-associated macrophages (TAMs) are indispensable in the hepatocellular carcinoma (HCC) tumor microenvironment. Xanthine oxidoreductase (XOR), also known as xanthine dehydrogenase (XDH), participates in purine metabolism, uric acid production, and macrophage polarization to a pro-inflammatory phenotype. However, the role of XOR in HCC-associated TAMs is unclear. METHODS: ). We determined metabolic differences using specific methodologies, including metabolomics and metabolic flux. RESULTS: T cells. CONCLUSIONS: The XOR-IDH3α axis mediates TAM polarization and HCC progression and may be a small-molecule therapeutic or immunotherapeutic target against suppressive HCC TAMs. IMPACT AND IMPLICATIONS: T-cell exhaustion via the upregulation of immunosuppressive metabolites, including adenosine and kynurenic acid. Given the prevalence and high rate of incidence of HCC and the need for improved therapeutic options for patients, our findings identify potential therapeutic targets that may be further studied to develop improved therapies.