PDCD1 and cancer: GBP1-related genes were more enriched in immune-related GO terms (lymphocyte-mediated immunity and regulation of natural killer cell-mediated immunity), KEGG pathways (PD-L1 expression and PD-1 checkpoint pathway in cancer and THF signaling pathway), and Reactome pathways (adaptive immune system and interferon signaling) for patients with CESC, TGCT, and HNSC compared to those with KIRP, UCEC, and LAML (Figure 4C).