Fig. 1

Isobolograms of the plot between combination index (CI) and fa in U937 (black symbol) and HepG2 (white symbol). fa = fraction affected by D (i.e., percentage antiproliferation/100). Isobolograms of the combination of compounds when P. kesiya was fixed (a, c; square), and when melphalan was fixed (b, d; circle) in each cancer cell lines