TGFB1 and neoplasm: Exosomes are also involved in different soluble factors such as check-point receptor ligands (PD-L1), inhibitory cytokines (IL-10 and TGF-β1), death receptor ligands (FasL), ectoenzymes, and prostaglandin E2 responsible for antitumor immunity in the tumor microenvironment (84, 85).