[Plasma proteasome 20S activity in children treated for acute lymphoblastic leukaemia]

THE AIM of our study was: to determine the proteasome 20S activity in plasma of patients treated for acute lymphoblastic leukaemia.

Plasma proteasome activity was measured in children (n=16) at two points: at diagnosis and on the 33rd day using the spectrophotometric method with peptidic substrate and selective proteasome activator 0.03% SDS.

1. At diagnosis we observed high activity of the proteasome 20S in comparison to control (p<0.005). After haematological remission the proteasome 20S activity lowered by about 50% (p<0.05). 3. We did not find the influence of immunophenotype, initial leucocytosis, LDH activity and hepatosplenomegaly on initial proteasome values.

Dynamic changes of the proteasome 20S activity confirm its participation in cancerogenic process. Proteasome 20S activity may be an effective indicator in the monitoring of anticancer treatment.