CA9 and renal carcinoma: They suggested 10 proteins for renal cancer exsome biomarker, 5 of which are abundant in renal cancer patients; matrix metalloproteinase 9 (MMP-9), ceruloplasmin (CP), podocalyxin (PODXL), dickkopf related protein 4 (DKK4) and carbonic anhydrase IX (CAIX).