1. N87-TM model generation and characterization.
N87-TM model generation and characterization. A, Schematic model of cyclical dosing paradigm used to generate T-DM1 resistant cells. Parental cells were dosed with T-DM1 for 3 days, followed by a washout and recovery period. This process was cycled multiple times until a T-DM1 resistant population emerged. B, Parental N87 (closed circle) and two T-DM1–resistant populations (open square and open circle), selected simultaneously (N87-TM-1 and N87-TM-2), were treated with T-DM1 for 4 days. Cell viability is plotted against ADC payload concentration. C–E, Whole-cell lysates from parental and T-DM1–resistant N87 cells were separated by SDS-PAGE and levels of MDR1 (C), MRP1 (D), and HER2 (E) were determined by immunoblot analyses. Whole-cell lysates from positive and negative control cell lines for MDR1 (KB85 and KBV1) and MRP1 (A549 and H69AR) are shown. F, Parental and T-DM1–resistant N87 cells were treated with a trastuzumab-ADC conjugated to a non-cleavable linker and auristatin payload for 4 days. Cell viability is plotted against ADC payload concentration. G, Parental and T-DM1–resistant N87 cells were treated with a trastuzumab–ADC conjugated to a cleavable-linked auristatin payload for 4 days. Cell viability is plotted against ADC payload concentration.
Matthew Sung et al. Mol Cancer Ther 2018;17:
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