The transition from an epithelial to mesenchymal cell phenotype (EMT) and its reverse mesenchymal-epithelial transition (MET) are essential for wound healing and many other normal, physiological, developmental processes; these fundamental cellular changes have also been implicated in cancer metastasis and organ fibrosis. During the EMT process, epithelial cells lose their apical-basal polarity and cell-cell adhesive properties and gain migratory and invasive properties, thereby exhibiting the characteristics of mesenchymal stem cells. In contrast, during the MET process mesenchymal cells lose their motility and show an increased number of cell-cell adhesions. 

Scientists have implicated EMT in metastasis and are thus targeting EMT/MET pathways as a potential strategy for cancer treatment. As researchers investigate the physiological mechanisms implicated in metastasis, they need access to credible cell models that demonstrate the forward and retrograde transition from an epithelial to a mesenchymal phenotype. To help researchers in the fight against cancer and the development of new treatment options, ATCC scientists created reporter cell lines that enable the real-time monitoring of EMT. 

The HCT116 VIM RFP, A549 VIM RFP, and MDA-MB-231 VIM RFP cell lines were generated by using CRISPR/Cas9 genome-editing technology to integrate a red fluorescent protein (RFP) reporter molecule before the stop codon at the last exon of the endogenous vimentin gene. This genetic manipulation enables researchers to track the EMT status of cells by monitoring RFP expression and to gain insight into this phenomenon in colon, lung, and breast cancer models.