CD274 and neoplasm: In addition, gemcitabine can reduce the number of immunosuppressive cells (such as myeloid suppressor cells) in the tumor microenvironment to a certain extent, thereby improving the local immune status and converting “cold” tumors into “hot” tumors (referring to tumors with less immune cell infiltration, while “hot tumors” contain abundant immune cells (Chen and Mellman, 2013), creating conditions for the application of immunotherapy drugs (such as PD-1/PD-L1 inhibitors).