mitoguazone and Leukemia--Myelogenous--Chronic--BCR-ABL-Positive

The present study proved that TGF-beta 1 significantly inhibited the growth of K 562 cells. The drop in cell numbers after 24 h incubation with increasing concentrations of TGF-beta 1 (0.01, 0.1, 1.0, 10.0 ng/ml) was accompanied by significant suppression of the activity of two key enzymes of polyamine biosynthesis: ornithine decarboxylase (ODC) and S-adenosylmethionine decarboxylase (SAMDC). In contrast to ODC and SAMDC activity, TGF-beta 1 did not significantly affect the absolute concentration of spermidine and spermine in K 562 cells. We suppose that the lack of an evident drop in concentration of spermidine and spermine in spite of a significant decrease in ODC and SAMDC activity in K 562 cells exposed to TGF-beta 1 resulted from the uptake of polyamines from the extracellular space.

Topics: 1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine; Adenosylmethionine Decarboxylase; Apoptosis; Cell Division; Cell Line; Dose-Response Relationship, Drug; Eflornithine; Humans; Isoquinolines; Kinetics; Leukemia, Myelogenous, Chronic, BCR-ABL Positive; Mitoguazone; Ornithine Decarboxylase; Piperazines; Polyamines; Protein Kinase Inhibitors; Putrescine; Spermidine; Spermine; Transforming Growth Factor beta; Tumor Cells, Cultured