For instance, expression of METTL3 in macrophages was suggested to synergize with PD-1-based therapy in B16 melanoma (6), and METTL3 and METTL14 have been shown to regulate immune response to anti-PD-1 treatment in melanoma and colorectal carcinoma (7). This evidence concerns the gene PDCD1 and colorectal carcinoma.