Figure 3

Paclitaxel and olaparib resistance are reversible following combination treatment with the P-glycoprotein inhibitors verapamil and elacridar. MTT chemosensitivity assays were used as described in Materials and Methods section to compare cell viability following exposure to serial dilutions of paclitaxel and olaparib in A2780, A2780pacR and A2780olapR cells in the presence and absence of combination treatments (5 μM and 10 μM) with the P-glycoprotein inhibitors (A–C) verapamil and (D–F) elacridar.