Plasticity between Epithelial and Mesenchymal States Unlinks EMT from Metastasis-Enhancing Stem Cell Capacity

In this study we studied the presence of tumor cells that underwent epithelial-to-mesenchymal transition within polyoma middle T antigen (PyMT) breast tumors. For this we dissociated tumors and isolated Ecad positive tumor cells by FACS sorting. We confirmed that PyMT tumors contain a small set of tumor cells that have undergone EMT in the primary tumor and that E-cadherin can be used as a marker on single cell level for mesenchymal status in this model. (i) We isolated primary tumors from mice, dissociated the tumors and FACS-sorted for single Ecad positive tumor cells, after this we performed single cell sequencing of the cells. (ii) We isolated CTCs and solid tumor cells from mice, dissociated the tumors and FACS-sorted for single Ecad positive and negative cells, after this we performed single cell sequencing of the cells.