Patient-derived xenograft (PDX) models

Human SCLC PDX models JHU-LX22, JHU-LX-44, JHU-LX-48 and JHU-LX-110 were established by using dissociated cells from resected PDX tumors (gift from C. Rudin and J.T. Poirier, Memorial Sloan Kettering Cancer Center, NYC) (Poirier et al., 2015). Cells (1 × 10⁶) were centrifuged, resuspended 1:1 (vol/vol) in matrigel and HITES media (Corning) and injected subcutaneously in the flank of 6–8 week old female NGS mice. Animals were sacrificed 6–8 weeks after implantation, tumors were collected and processed for ChIP (see below). All animal work was approved by the University of Texas Southwestern (Dallas, TX) Institutional Animal Care and Use Committee.