Figure 3.

Combination index plots of Chou-Talalay and impact of drug sequence in HL-60 cells. Composite dose-response curves were constructed for drugs alone and in combination as described in Methods. The respective fraction affected (F_a) was interpolated at 10 percent Intervals and the values used to compute the combination index for simultaneous administration of CP-4055 (open circles), for CP-4055 given 24 h prior to (open triangles) or 24 h after (open squares) the second drug in the combination listed in each panel. For cytarabine, only simultaneous combinations are shown combined with CP-4055 (closed circles), and with gemcitabine (closed triangles).