Figure 4 from Nuclear Focal Adhesion Kinase Protects against Cisplatin Stress in Ovarian Carcinoma

FAK KO and reexpression show that nuclear FAK promotes cisplatin but not paclitaxel resistance in human OVCAR3 cells. A, Immunoblots of cultured FAK KO OVCAR3 (clone AB21) and GFP-FAK-WT or FAK-NLS⁻ reconstituted AB21 cells for HA-tag (at FAK C-terminal), FAK pY397, and β-tubulin as a loading control. B, FAK-WT, and FAK-NLS⁻ OVCAR3 cells were evaluated for cisplatin cytotoxicity after 48 hours in culture. Shown is percent cell viability vs. cisplatin concentration (μmol/L, log₁₀), and points are means of triplicate samples ± SD (n = 3 independent experiments). C, Determination of IC₅₀ values to cisplatin as performed in B (***, P < 0.001). D, FAK-WT and FAK-NLS⁻ OVCAR3 cells were evaluated for paclitaxel cytotoxicity (μmol/L, log₁₀) after 48 hours in culture. E, Analysis of OVCAR3 FAK-WT and FAK-NLS⁻ cells for growth in culture and (F) in the presence of 0.5 μmol/L cisplatin for 72 hours. Values are means ± SD from two independent experiments with triplicate points and FAK-WT values set to 1 (***, P < 0.001; ns not significant). G, Representative images of crystal violet–stained OVCAR3 FAK-WT and FAK-NLS⁻ cell colonies formed in the presence of 0, 0.5, or 1.0 μmol/L cisplatin after 10 days. H, Quantitation of FAK-WT (green bars) and FAK-NLS⁻ (blue bars) colony formation. Values are means ± SD from three independent experiments with triplicate points (*, P < 0.05).