[Cystatins: cysteine proteases regulation and disturbances in tumors and inflammation].

Cystatin C belongs to the group of wide spread extracellular cysteine protease inhibitors. Using ELISA kits it was shown that the highest cystatin C concentration was in human cerebrospinal fluid and low cystatin C concentration was in human urine. In healthy young persons serum cystatin C concentration was lower than in elder patients (50-65 year old). In patients with hemoblastoses (lymphoma, lymphogranulomatosis) increased serum cystatin C concentration was normalized after effective antitumor therapy. According to these data one can conclude that serum cystatin C concentration can be used as one of the prognostic criteria in patients with several kinds of hemoblastoses.