CD63 and lung adenocarcinoma: Lung adenocarcinoma-derived exosomal miR-19b-3p (size range of 100 nm, marker proteins CD9, CD81) and miR-10b (bilayer membrane structure, typical “cupped” structure, marker proteins TSG101,CD63,CD81) facilitate macrophage polarization to the M2 type to promote lung adenocarcinoma development [70,71].