SOX9 and breast carcinoma: Intriguingly, the results also revealed that HR+ breast cancer had a decreased SOX9 expression and an increased SOX9 methylation relative to normal tissue or TNBC subtype, indicating that SOX9 tended to be epigenetically and transcriptionally silenced in HR+ breast cancers, similar to our IHC results (Fig. 3c, d; Table 1).