PDCD1 and melanoma: For example, miR-28 interacts with PD-1/PD-L1, BTLA, and Tim-3 in melanoma [112]; miR-424 interacts with PD-1/PD-L1 and CD80/CTLA-4 in OC [108]; miR-128 interacts with B7-H3 and Gal-3 in CRC [118,127]; miR-138 interacts with PD-1 and CTLA-4 in glioma [109].