Table 1

Cytotoxic activity of 4-hydroperoxycyclophosphamide (4-HC)a

IC50
LM6LM6-#6LM6-neoP
4-HC2.34 μm0.41 μm2.10 μmP < 0.01
4-Hydroperoxy-didechloroclo-phosphamide (4-HDC)5.12 μm5.16 μm6.11 μmP > 0.1
Methotrexate (MTX)63.0 μm71.2 μm78.6 μmP > 0.5
Cisplatin (CDP)0.15 μm0.10 μm0.12 μmP > 0.1
Adriamycin (ADR)11.90 μm12.1 μm10.67 μmP > 0.1
  • a LM6 and LM6-#6 cells [Fas expression 36.2 versus 80.5% (Fig. 2)<$REFLINK>] were incubated with various concentrations of 4-HC, 4-HDC, MTX, CDP, or ADR for 24 h. The IC50 of each drug was determined using the colony-forming assay.