Fig. 1. Isobolograms (A) and (B) Combination Index (CI) values of the interaction between Cxb with Doc against human lung Cancer cells.

Different concentrations of Cxb were employed to study the effect on IC50 of Doc. Variable ratios of drug concentrations and mutually non-exclusive equations were used to determine the CI. The CI values represent mean of four experiments. CI >1.3: antagonism; CI 1.1–1.3: moderate antagonism; CI 0.9–1.1: additive effect; CI 0.8–0.9: slight synergism; CI 0.6–0.8: moderate synergism; CI 0.4–0.6: synergism; CI 0.2–0.4: strong synergism.