CA9 and hereditary clear cell renal cell carcinoma: Raimondo et al. [125] studied exosomes in urine samples from nine patients with renal cell carcinoma and 23 healthy controls, and found that matrix metalloproteinase 9 (MMP9), ceruloplasmin (Cp), podocalyxin (PC), DKK 4, and carbonic anhydrase IX (CAIX) were highly expressed.