SOX10high Cells within Mammary Tumo

SOX10high Cells within Mammary Tumors Exhibit Dedifferentiated and EMT-like FeaturesEctopic overexpression of SOX10 reprograms mammary epithelial cells into a mesenchymal-like cell state (Dravis et al., 2015). Strikingly, analysis of sections from C3-1 mammary tumors revealed that SOX10high cells expressed low levels of epithelial cytokeratins, whereas cells with lower SOX10 expression retained epithelial markers (Figures 5A and 5B ). To better quantify the relationship between SOX10 and epithelial markers, we dissociated C3-1 mammary tumors to single cells, and found that >80%–90% of SOX10high cells had undetectable levels of KRT8 and KRT14 (Figures 5C and 5D). SOX10high tumor cells form tumorspheres in 3D culture conditions at low efficiency, and these tumorspheres exhibited high levels of SOX10 and low levels of cytokeratins (Figure 5E). Thus SOX10high cells in these basal-like mammary tumors showed reduced levels of keratin markers associated with the epithelial state and mammary cell differentiation