Wang and coauthors recently reported 12 hot tumor-related genes (CXCR3, CXCR4, CXCL9, CXCL10, CXCL11, CCL5, CD3, CD4, CD8a, CD8b, CD274, and PDCD1) and three cold tumor-related genes (CXCL1, CXCL2, and CCL20) constitute the TIP gene signature using a text-mining approach (Wang et al., 2021), which is significantly associated with the survival outcomes of cancer patients and presents better predictive ability in immunotherapeutic responses than widely used immune signatures such as tumor mutation burden (TMB) and tumor immune dysfunction and exclusion (TIDE). This evidence concerns the gene PDCD1 and cancer.