Moreover, it will be important to analyze the influence of different exercise modalities on cytokines (such as IL-6, IFN-γ, and IL-10), and enzyme expression/activity (e.g., IDO1, KATs, and KMO) in different cell types and tissues (e.g., immune cells, muscle tissue, and tumor tissue) within the KYN pathway. This evidence concerns the gene IL10 and neoplasm.