PDCD1 and cancer: Huang et al. [68] discovered that the tumor suppressor tuberous sclerosis complex subunit 1/2 (TSC1/2) effectively regulated PD-L1 expression in vitro and that its knockout enhanced PD-L1 transcription and membrane expression, thereby sensitizing cancer cells to PD-1 treatment in a murine KrasG12D/Trp53−/− lung cancer model.