For example, m6A modification of related mRNA can be inhibited by knockout of methyltransferase METTL3/14, and the production of CD8 positive T cells, IFN‐γ, CXCL‐9 and CXCL‐10 in the tumour microenvironment can be increased through IFN‐γ‐STAT1‐IRF1 signalling pathway, thus enhancing the effect of anti‐PD‐1 therapy in the treatment of melanoma.11 This evidence concerns the gene PDCD1 and neoplasm.