Our analysis revealed a widespread negative correlation between the co-expression of these genes and the expression of genes encoding immune checkpoint molecules, such as CD274, PDCD1LG2, PDCD1, CTLA4, TIGIT, and CD244, across multiple cancer types, including gastrointestinal, reproductive, nervous, respiratory, ocular, and hematopoietic cancers. Here, PDCD1 is linked to hematopoietic and lymphoid cell neoplasm.