Drug treatment.

Trastuzumab was kindly provided by Genentech Inc. (MTA OR-215366). Human iPSC-CMs were treated with trastuzumab or doxorubicin (Sigma-Aldrich) for 7 days. Human IgG (Sigma Aldrich) was used as a control treatment unless noted. For the co-treatment experiment, cells were treated with AICAR (Sigma-Aldrich), rosiglitazone (Thermo Fisher Scientific), metformin (Sigma-Aldrich), or lipoic acid (Cayman Chemical) at 0.001 to 1 mM, or rapamycin (Sigma-Aldrich) at 0.001 to 1 μM in the presence of trastuzumab at 1 μM for 7 days. The medium containing fresh drug was replaced every 3 days.