Table 1.

Combination index values induced by sequential treatments

		MCF-7			BRC-230
		CI value at inhibition of			CI value at inhibition of
Drug combination	Combination ratio	75%	90%	95%	75%	90%	95%
Dox→Pacl	1:1	0.3	0.3	0.4	0.1	0.2	0.2
Dox→Pacl→48-h washout→5-FU	1:1:10	0.0005	0.002	0.005	0.002	0.007	0.02

5-FU, 5-fluorouracil; CI, combination index; Dox, doxorubicin; Pacl, paclitaxel.