Figure 4

Cell-type-specific cytokeratin expression in breast cancer subgroups. The log ratios for the cytokeratin probes for the van't Veer and colleagues tumor samples [11] are colored by group as in Fig. 3. (a) Co-expression of the luminal KRT8 and KRT18 is found in the estrogen receptor (ER)-positive tumors (black, blue and yellow) and in the ERRB2-positive tumors (purple). (b) Co-expression of the basal KRT5 and KRT14 is found in the ER-negative tumors (red) and in the BRCA1 mutant tumors (dark green).