The specificity of the antibodies for epithelial (EpCAM, E-cadherin, CK8, CK18, and CK19) and mesenchymal (vimentin, fibronectin, and N-cadherin) markers used in the negFACS-IF:E/M platform were initially validated in various breast cancer cell lines (Supplementary Figure S1). Here, FN1 is linked to breast cancer.