PDCD1 and cancer: The blue cluster was related to “clinical research,” focusing on the clinical efficacy of conventional treatments, with keywords such as “biomarkers,” “chemotherapy,” “immune checkpoint,” “cancer immunotherapy,” “PD-L1/PD-1,” and “prognosis.” The yellow cluster was mainly related to the “anti-tumor mechanism of TCM regulating immunity,” with keywords such as “ferroptosis,” “immunogenic cell-death,” “autophagy,” “cell-cycle arrest,” and “mitochondria”.