FRK and breast cancer: We examined the relationship between the expression of FRK with mesenchymal markers Vimentin (VIM), N-cadherin (CDH2), fibronectin (FN1), snail family transcriptional repressor 2 (SNAI2), twist family bHLH transcription factor 1(TWIST1), and epithelial markers E-cadherin (CDH1) and Keratin 18 (KRT18), in breast cancer cell lines stratified under Basal B (BB), Basal A (BA) and luminal (LU) (Supplementary Table 5, Figure 10).