PTAFR and neoplasm: After UVB reaches the skin, platelet-activating factors (PAFs) and platelet-activating factor receptor (PAF-R) agonists can generate to bind with PAF-R for the generation of UVB-mediated ROS and subcellular microvesicle particles (MVP) carrying the mediators with the ability of mediating systemic immunosuppression and thereby enhancing tumor growth are released [110].