In specific, TIS is referred to as an 18‐gene signature (CCL5, GZMK, CD3D, CD3E, CD2, HLA‐DRA, IL2RG, NKG7, CIITA, CXCR6, LAG3, TAGAP, HLA‐E, CXCL13, IDO1, CXCL10, STAT1, and GZMB), which was related to the response to ICIs in various cancers.21, 22. The gene discussed is CIITA; the disease is cancer.