Effects of MCL-1 antisense oligonucleotides and inhibitory drugs on growth and viability of neoplastic mast cells exhibiting KIT D816V. (Top row) Effects of various concentrations of PKC412 (A), AMN107 (B), STI571 (imatinib) (C), or 2CdA (D) on ³H-thymidine uptake by HMC-1.2 cells transfected with a scramble control (▪) or MCL-1 antisense oligonucleotides (Antisense) (each 80 nM) (•). Results are expressed as percentage of control (ie, scramble control) without inhibitory drug and represent the mean ± SD of 3 independent experiments. *P < .05. (Middle row) Effects of MCL-1 antisense oligonucleotides (Antisense) or scramble control (each 100 nM) applied with PKC412 (A), AMN107 (B), STI571 (imatinib) (C), or 2CdA (D) or without the respective drug on cell viability (ie, percentage of apoptotic cells). Results represent the mean ± SD of 3 independent experiments (*P < .05). (Bottom row) Using CalcuSyn software, analyses of dose-effect relationships of PKC412 (A), AMN107 (B), STI571 (imatinib) (C), or 2CdA (D) and MCL-1 antisense–induced apoptosis in HMC-1.2 cells were calculated according to the median effect method of Chou and Talalay.⁵⁷  CI less than 1 indicated synergism.