Chronic myelogenous leukemia (CML) is characterized by a chimeric BCR/ABL gene giving rise to fusion protein with increased tyrosine kinase activity. Genistein is a protein tyrosine kinase inhibitor. The aims of the present study were: (1) to evaluate the effects of genistein on the growth of primitive (long-term culture-initiating cells, LTC-IC) and committed | multipotent (CPUMix), erythroid (BFU-E), granulocyte-macrophage (CFU-GM)t progenitors; (2) to determine whether genistein could enrich nonleukemic progenitors. Continuous exposure to genistein ( I -100 p.M) induced a dose-dependent suppression of CPU-Mix, BFU-E and CPU-CM growth. Prcincubation of CML cells with genistein (200 pM, 1-18 hrs) induced a time-dependent growh suppression, while sparing a substantial proportion of LTC-IC (86 ±7% and 33 ±4% after 1 and 18 hr prcincubation, respectively). Terminal deoxynucleotidyl transferee assay and DNA electrophoresis demonstrated apoptosis of a significant proportion of gcnistein-treated CML cells. Individual colonies were harvested and analyzed by reverse transcription polymerase chain reaction (RT-PCR) for the expression of BCR/ABL mRNA. As compared to control cultures, continuous exposure to genistein significantly reduced the mean (±SD) percentage of BCR/ABL+ progenitors (76 ±18% vs 24 ±12%, P £.004). Similarly, preincubation of marrow cells with genistein resulted in a significant reduction of BCR/ABL+ progenitors (75 ±16 vs 21 ±10, P E.002). Preincubation with genistein reduced BCR/ABL LTC-IC from 80 ±3% to 30 ±7%. In conclusion, we demonstrate that: (a) genistein inhibits CML CPU-Mix, BFU-E, CFU-GM while sparing a substantial proportion of LTC-IC; (b) growth inhibition selectively affects leukemic CFUGM and LTC-IC while sparing normal progenitors; (c) the antileukemic effect of genistein is likely to occur by triggering apoptosis of leukemic progenitors.
Genistein trjggers apoftosis of chronic myelogenous leukemia cells and selects bcr/abl negative progenitors
Carlo Stella C.
1996-01-01
Abstract
Chronic myelogenous leukemia (CML) is characterized by a chimeric BCR/ABL gene giving rise to fusion protein with increased tyrosine kinase activity. Genistein is a protein tyrosine kinase inhibitor. The aims of the present study were: (1) to evaluate the effects of genistein on the growth of primitive (long-term culture-initiating cells, LTC-IC) and committed | multipotent (CPUMix), erythroid (BFU-E), granulocyte-macrophage (CFU-GM)t progenitors; (2) to determine whether genistein could enrich nonleukemic progenitors. Continuous exposure to genistein ( I -100 p.M) induced a dose-dependent suppression of CPU-Mix, BFU-E and CPU-CM growth. Prcincubation of CML cells with genistein (200 pM, 1-18 hrs) induced a time-dependent growh suppression, while sparing a substantial proportion of LTC-IC (86 ±7% and 33 ±4% after 1 and 18 hr prcincubation, respectively). Terminal deoxynucleotidyl transferee assay and DNA electrophoresis demonstrated apoptosis of a significant proportion of gcnistein-treated CML cells. Individual colonies were harvested and analyzed by reverse transcription polymerase chain reaction (RT-PCR) for the expression of BCR/ABL mRNA. As compared to control cultures, continuous exposure to genistein significantly reduced the mean (±SD) percentage of BCR/ABL+ progenitors (76 ±18% vs 24 ±12%, P £.004). Similarly, preincubation of marrow cells with genistein resulted in a significant reduction of BCR/ABL+ progenitors (75 ±16 vs 21 ±10, P E.002). Preincubation with genistein reduced BCR/ABL LTC-IC from 80 ±3% to 30 ±7%. In conclusion, we demonstrate that: (a) genistein inhibits CML CPU-Mix, BFU-E, CFU-GM while sparing a substantial proportion of LTC-IC; (b) growth inhibition selectively affects leukemic CFUGM and LTC-IC while sparing normal progenitors; (c) the antileukemic effect of genistein is likely to occur by triggering apoptosis of leukemic progenitors.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
