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ara-C. Doxorubicin and ara-C showed strong potency against MA9.3
AML cells with IC50 values of 86 5 nM and 0.92 0.03 M respec-
tively; these agents had IC50 values against CD34+ blood stem/pro-
genitor cells of 76 18 nM and 0.59 0.09 M. These agents had
very limited selectivity. The therapeutic index for doxorubicin
was 0.9 0.2 and the index for ara-C was 0.6 0.1. The negative in-
dex for ara-C was statistically significant but small. Thus, these two
agents showed low selectivity. We then determined if other com-
mercially available DNA-modifying agents were selective, as a base
of comparison for our ROS-activated DNA-modifying agents. We
chose cisplatin for its high therapeutic use and chlorambucil for
its utilization in chronic lymphocytic leukemia. The IC50 value for
we would like to thank the University Research Council for funding
an interdisciplinary research award to JM and EJM. JCM is sup-
ported by an Institutional Clinical and Translational Science Award,
NIH/NCRR Grant Number 1UL1RR026314-01, and a Center of
Excellence in Molecular Hematology P30 award (DK090971). JCM
is a Leukemia and Lymphoma Scholar. We acknowledge Larry Sal-
lans and Jeffrey Bailey for technical assistance.
l
l
Supplementary data
Supplementary data associated with this article can be found, in
cisplatin was 14 0.7
against MA9.3 AML cells. Against CD34+ blood stem/progenitor
cells, the former had an IC50 value of 15 M, while the latter
had an IC50 value of 11 M. The therapeutic index for cisplatin
lM and for chlorambucil was 8.7 0.3 lM
2
l
References and notes
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lM and 7 had an IC50 value
l
1
l
l
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1 lM
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l
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Acknowledgments
We thank the University of Cincinnati Technology Accelerator
for funding the collaborative efforts of EJM and JCM. In addition,