Supplementary Fig. S3.

of Fig. 4: ROR1+ cells are resistant to T-DM1. (a) MCF-7-HER2⁺ cells were cultured in CSC medium and treated with either vehicle (DMSO) and/or T-DM1 for 5 days, harvested and FACS sorted for ROR1⁺ and ROR1⁻ populations. Sorted cells were re-cultured in supplemented CSC medium for 10 days and analyzed for the sphere growth efficiency from each subpopulation [p = .01 for T-DM1 treatment; p = ns (not significant) for vehicle, unpaired two-sided t-test; Scale bar: 100 μM]. (b) Patients tumor cells, (c) HCC1954 and (d) MCF-7-HER2+ cells were sorted for ROR1, treated with increasing concentrations of T-DM1 for 5 days and cell survival assessed by WST-1 assay (Bar graph represents the mean +/− SE, n = 3; run in triplicate; p = .05).