Table 1 : Combination index (CI) of co-treatment with Tamoxifen and Doxorubicin.


Cell line Combination Combination index (CI)

BT483 0.5µM Dox / 4µM Tam 0.88
  1µM Dox / 4µM Tam 1.25
231eB 0.5µM Dox / 4µM Tam 0.87
  1µM Dox / 4µM Tam 1.12
231neo 0.5µM Dox / 4µM Tam 1.54
  1µM Dox / 4µM Tam 0.71
MDA-MB-231 0.5µM Dox / 4µM Tam 3.01
  1µM Dox / 4µM Tam 2.02

CI was defined as follows: CI = (D)1/(Dx)1 + (D)2/ (Dx)2 + (D)1(D)2/(Dx)1 (Dx)2(Dx)1 and (Dx)2 are the concentrations of drug 1 and drug 2, which alone produce x% effect. (D)1 and (D)2 are the concentrations of drug 1 combined with drug 2 to obtain the same response as drug 1 alone or drug 2 alone.

Huang et al.Journal of Pharmaceutical Technology and Drug Research  2013 2:12DOI : 10.7243/2050-120X-2-12