In vitro sensitivity of hematopoietic progenitors to tiazofurin in refractory acute myeloid leukemia and in the blast crisis of chronic myeloid leukemia.
The effect of Tiazofurin (TR) on the in vitro growth of bone marrow (BM) and peripheral blood (PB) leukemic progenitors was investigated in 29 patients. Nineteen of the patients were suffering the blast crisis of chronic myeloid leukemia (bcCML) and ten patients refractory acute myeloid leukemia (AML). PB and BM mononuclear cells were cultured in methylcellulose alone or with concentrations of TR ranging between 10 and 200 microM. TR produced a dose dependent inhibition of colony forming unit (CFU)-blast growth in all the samples tested from BM and PB. The most effective concentrations of TR used were 150 and 200 microM, while concentrations of less than 50 microM TR were not adequate for 50% inhibition of cell growth (IC50). Differences were found in the response of CFU-blasts to TR related to the type of underlying leukemia. Inhibition of CFU-blast growth was more pronounced in bcCML than in AML in both the BM and PB samples. The concentration of TR required to induce IC50 in bcCML was 50 microM, while the same effect in AML required a concentration of 150 microM. Analysis of the control samples also revealed that CFU-blasts from bcCML produced smaller numbers of colonies, though these differences were not statistically significant. It has therefore been demonstrated that TR has strong in vitro anti-leukemic activity, more pronounced in bcCML than in refractory AML. We thus feel this study gives further rationale for the clinical application of TR, and would strongly support this.
Colovic
M
M
Institute of Haematology Clinical Centre of Serbia, Koste Todorovica 2, 11000 Belgrade, Serbia, Yugoslavia. marcolov@eunet.yu
Sefer
D
D
Bogdanovic
A
A
Suvajdzic
N
N
Jankovic
G
G
Atkinson
H D E
HD
Milenkovic
P
P
D000328:Adult; D000368:Aged; D000964:Antimetabolites, Antineoplastic / Q000494:pharmacology*; D001752:Blast Crisis; D001773:Blood Cells / Q000187:drug effects; D001854:Bone Marrow Cells / Q000187:drug effects; D019008:Drug Resistance, Neoplasm; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005260:Female; D006412:Hematopoietic Stem Cells / Q000187:drug effects*; D006801:Humans; D020128:Inhibitory Concentration 50; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000097:blood / Q000473:pathology*; D007951:Leukemia, Myeloid / Q000097:blood / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D014411:Neoplastic Stem Cells / Q000187:drug effects*; D012254:Ribavirin / Q000031:analogs & derivatives / Q000494:pharmacology*; D014407:Tumor Cells, Cultured / Q000187:drug effects; D014410:Tumor Stem Cell Assay
D000964:Antimetabolites, Antineoplastic; D004791:Enzyme Inhibitors; D012254:Ribavirin; C033706:tiazofurin