For purine nucleosides, oral supplementation of inosine enhanced the anti-tumor ability of T cells in mouse CRC, bladder cancer and melanoma models under the condition of combined IFN - γ co stimulation, and played a synergistic role with immunotherapy; peritumoral (intraperitoneal) dosing that increases local inosine also elevates intratumoral IFN-γ and constrains tumor growth [24, 180, 255]. Here, IFNG is linked to colorectal carcinoma.