Fig. 2

Isobologram analysis of a HepG2 cells after 48 and 72 hrs. of exposure to sorafenib in combination with CPT b Huh7 cells after 48 and 72 hrs. of exposure to sorafenib in combination with CPT. The zones of antagonistic (upper), synergistic (lower), and additivity (on the line) are illustrated. The data point’s distance from its respective line indicates the degree of synergism in this drug combination (same color). The results show that there is synergism at the IC₅₀ level. The data points in circles are the means of three different replicates.