The most well‐known and most studied are the immune checkpoints which are expressed on the surface of tumor cells, such as programmed cell death 1 ligand 1 (PD‐L1) and cytotoxic T lymphocyte‐associated antigen‐4 (CTLA‐4), which can bind to receptors on immune cells and act as an inhibitory signal to suppress immune cells function.13 Recently, several studies have shown that PD‐L1 can also be expressed on extracellular vesicles (EVs) secreted by cancer cells,14, 15 and the expression level is related to tumor progression. Here, CD274 is linked to cancer.