The effects of acetaldophosphamide, a novel stable aldophosphamide analogue, on normal human and leukemic progenitor cells in vitro: implications for use in bone marrow purging.
Acetaldophosphamide (A-ALD), a novel in vitro active and stable derivative of aldophosphamide, kills human bone marrow-derived granulocyte-macrophage colony-forming cells (GM-CFC) independent of the cell cycle. The surviving fraction of GM-CFC is an exponential function of the drug concentration and time of exposure. Variation of marrow light-density cell concentration between 2 x 10(6) and 10 x 10(6)/ml does not significantly influence its GM-CFC toxicity. Marrow depleted of GM-CFC by A-ALD subsequently generates GM-CFC when grown in suspension cultures. During the early period after treatment with A-ALD the number of surviving GM-CFC (size of surviving GM-CFC compartment) does influence the speed of the GM-CFC repopulation in suspension cultures. The importance of the number of surviving GM-CFCs for the growth and maintenance of GM-CFC population in such suspension cultures diminishes with time. No significant differences are observed after 2 wk, indicating that the ancestor stem cell population and its regenerative potential responsible for in vitro hematopoiesis have not been significantly affected by the drug treatment. A-ALD-treated progenitor cells retain their ability to integrate with the previously established marrow stromal cell layer and generate GM-CFC within this layer to an extent comparable to that of untreated marrow cells. The effect of A-ALD on human hematopoiesis is comparable to that of 4-hydroperoxycyclophosphamide. Its advantage over 4-hydroperoxycyclophosphamide is a greater stability in vitro. It has sparing effect on GM-CFC ancestor cells. Its toxicity to myeloid leukemia cell line (KBM-3)-derived clonogeneic cells is higher than to the GM-CFC. It is similar in doxorubicin-sensitive (KBM-3) and -resistant (KBM-3/DOX) leukemic cells. Thus, A-ALD appears to be a promising drug for in vitro purging of bone marrow cells.
Beran
M
M
Department of Hematology, University of Texas M.D. Anderson Hospital and Tumor Institute at Houston 77030.
Andersson
B S
BS
Wang
Y
Y
McCredie
K B
KB
Farquhar
D
D
D001853:Bone Marrow / Q000187:drug effects; D016026:Bone Marrow Transplantation; D002470:Cell Survival / Q000187:drug effects; D003520:Cyclophosphamide / Q000031:analogs & derivatives / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D006412:Hematopoietic Stem Cells / Q000187:drug effects*; D006801:Humans; D007938:Leukemia / Q000473:pathology*; D014411:Neoplastic Stem Cells / Q000187:drug effects*; D010752:Phosphoramide Mustards / Q000494:pharmacology*; D012038:Regeneration
D010752:Phosphoramide Mustards; C054580:acetaldophosphamide; D003520:Cyclophosphamide; C011272:perfosfamide