Figure 4. SOX2 expression is enriched in luminal-B and HER2-positive breast cancer subtypes. (A) Relative enrichment of SOX2 expression (213721_at) in breast cancer cell lines organized by luminal, basal A, and basal B sub-classes [38, 39]. (B) Box plots presents the SOX2 gene expression in primary breast tumors from the METABRIC project classified in distinct subtypes using 3-gene (left), PAM50 (middle), and integrative clusters (right) classifiers. The color line presents median, box shows interquartile region and whiskers – the highest (max) and the lowest (min) value.