Fig. 4

WEE1 kinase inhibition sensitizes MOC2 cells to NK killing via a tumor-specific mechanism. a MOC2 cells were cultured in increasing doses of AZD1775 (250–2000 nM) or DMSO volume equivalent for 18 h and apoptosis was assessed by annexin V/7AAD flow cytometry. Representative dot plots shown on left, quantified for early (annexin V⁺7AAD⁻) or late (annexin V⁺7AAD⁺) apoptosis on right. * indicates significant difference compared to control. b MOC2 cells were plated in increasing concentrations of AZD1775 (125–2000 nM) or DMSO volume equivalent and assays for cell proliferation and viability via impedance analysis, % loss of cell index at 48 h quantified on right. c MOC2 cells were exposed to AZD1775 (250 nM) or DMSO (control, volume equivalent) for 18 h and analyzed for cell surface marker expression by flow cytometry. IFNγ (20 ng/mL × 18 h) treatment of MOC2 cells or YAC cells were used as positive controls. d MOC2 cells were plated in AZD1775 250 (nM) or DMSO and cell index after exposure to KIL at a 6.25:1 E:T ratio was assessed by impedance analysis. In some wells, MOC2 cells were plated in AZD1775 (250 nM) or DMSO but washed three times before the addition of KIL (only MOC cells exposed to AZD before addition of KIL cells). In other wells, KIL were exposed to AZD1775 or DMSO for 24 h, then washed three times before being added to MOC2 cells (only KIL cells exposed to AZD before addition to MOC2 cells). % loss of cell index 48 h after the addition of KIL to MOC2 cells quantified on the right. Results presented are representative of three independent experiments with similar results. *, p < 0.05; **, p < 0.01; ***, p < 0.001; n/s, not significant