POU5F1 and breast cancer: To determine whether these CSC transcription factors are differentially expressed between AA and CA TNBC tumors and cell lines, we interrogated the TCGA PanCancer cohort and found Oct4 (Figure 5A), Nanog (Figure 5B), and Sox2 (Figure 5C) to be significantly (p < 0.001) highly expressed in tumors of the basal (TNBC) breast cancer subtype when compared to tumors of Her2, Luminal-A, or Luminal-B subtypes.