Mutation independent activation of the Notch pathway is associated with Lapatinib resistance in Her2+ breast cancer cell lines

We compared untreated HCC1419 cells with Lapatinib resistant HCC1419 cells that were either treated with Lapatinib for only 9 days before harvesting (drug tolerant persisters, DTPs) or were growing in the presence of Lapatinib (>70 days) (drug tolerant expanded persisters, DTEPs). We show that the Notch pathway is significantly over-expressed in DTEPs when compared to untreated cells. RNA-Seq of HCC1419 cells either untreated, treated with 1μM Lapatinib for 9 days or treated with 1μM Lapatinib for greater than 70 days