SOX2 and breast cancer: The genes that were upregulated in primary BC included MMPs (MMP2, MMP9, MMP11, MMP13, and MME), KRTs (KRT5, KRT14, and KRT 17), VCAM1, CXCL12, SCUBE2, TP63, and SFRP. Expression levels of SOX2 and OLIG2 were downregulated in primary BC compared to BCBM.