CD274 and neoplasm: In vitro studies demonstrated that PD-L1 found on tumor-derived extracellular vesicles can activate cAMP-response element binding protein (CREB) and signal transducer and activator of transcription (STAT) signaling that induce senescence and suppression in T cells by a mechanism that mainly targets the DNA damage and hyperactivation of the lipid metabolism that increase the cholesterol level and lipid droplet formation [37].