TABLE 1 Sorafenib/regorafenib cooperate with PI3K/AKT inhibitors to kill tumors cells
HuH7 and HCT116 cells (250–1500 cells/well) were plated in sextuplicate and allowed to attach for 12 hours. Cells, HuH7 [sorafenib + P-866] and HCT116 [regorafenib + MK2206], were treated with sorafenib (SOR, 2.0–4.0 μM), regorafenib (REGOR, 0.5–1.0 μM), PX-866 (0.5–1.0 μM), MK2206 (MK, 1.0–2.0 μM) for 24 hours. Media was removed, plates washed, and cells cultured for the next 10–14 days in media lacking drugs. After ∼10 days media was removed, plates washed, and cells fixed and stained. The number of colonies per plate (>50 cells per colony) was counted, plating efficiencies determined, and the relative changes in colony formation entered into the CalcuSyn for Windows program (Biosoft, Cambridge, UK) to determine synergy (n = 3). A combination index (CI) of less than 0.70 indicates a strong level of synergy.