IDO1 and neoplasm: Additionally, the expression of immune inhibitory markers CTLA-4 and the metabolic enzyme IDO1 was also significantly higher in the high-expression group, indicating a more complex tumor microenvironment with activated immune evasion mechanisms.Regarding immunotherapy-related biomarkers, the significant upregulation of IFNG suggests a strong Th1-type immune response, which is associated with a favorable potential for immunotherapy response.