PROGNOSTIC-SIGNIFICANCE OF PROTEIN-KINASE-C IN NEWLY-DIAGNOSED CHILDHOOD ACUTE LYMPHOBLASTIC-LEUKEMIA

The expression of protein kinase C (PKC) was analysed in newly diagnos ed cases of non-B acute lymphoblastic leukemia (NB-ALL) in children. B last cells obtained from 104 children with untreated NB-ALL were analy sed using the streptavidin-biotin-peroxidase method and the antibody M C5. Of the 104 patients with NB-ALL, 48 (=46%) showed positive stainin g for PKC. The relapse rate was significantly higher in NB-ALL with ex pression of PKC than in leukemia without expression of PKC (p=0.008). The relapse-free intervals in the PKC-negative leukemias were signific antly longer than in cases of PKC-positive leukemias (p=0.004). The ov erall survival times were also longer in NB-ALL without expression of PKC than in ALL with PKC-expression (p=0.03). The results of univariat e and multivariate analyses demonstrate that in addition to the clinic al prognostic indicators PKC expression is a significant prognostic fa ctor for relapse rate, relapse-free intervals, and overall survival ti mes in NB-ALL of children.