PDCD1 and neoplasm: The CellphoneDB analysis of ligand-receptor pairs showed that the interaction networks between UPP1high tumor cells and FOXP3+ Tregs/LAG3 + PDCD1 + CD8 + T cells were involved with numerous immune checkpoints, including CD274/PDCD1LG2_PDCD1, FGL1_LAG3, and NECTIN_TIGIT.