A. Dual fluorescent IHC of paraffin sections of BLBC PDX UCD46, UCD115, and UCD18 for CK5 (red)/CK17(green), CK5(green)/vimentin(VIM, red) or CK17(green)/vimentin(VIM, red) plus DAPI (blue) counterstain. Scale bars, 20 μm. B. sc RNA-seq of BLBC PDX was used to generate EMT scores based on a published 156 gene signature (37) in individual cells that were CK5/CK17+, CK5/CK17/vimentin(VIM)+, or vimentin(VIM)+. y-axes (positive, higher scores are more epithelial, negative, lower scores are more mesenchymal). Scatter plot plus means. One-way ANOVA/Kruskal-Wallis test was performed to assess statistical significance. *P<0.05, **P<0.01, ***P<0.001, ****P<0.0001, NS=not significant. C. EMT scores were generated as in (B) for RNA-seq data from MDA-MB-468 and BT-20 cells, comparing each of the three replicates of shCont and shCK5-22. Unpaired T-tests were used to determine statistical significance. ***P<0.001, ****P<0.0001.