KRT5 and cancer: Figure 2C shows that breast tumors stained positive for H3K27me3 display a consistent downregulation of CDKN1C compared with those negative for H3K27me3. Of important note, genes exhibiting the similar expression patterns to CDKN1C include KRT17, KRT5 and LAMB3 that have been validated to be EZH2 target in our previous study [23]. Thus, the data from both clinical breast tumor samples and cancer cell lines all support that CDKN1C downregulation in breast cancer is associated with a higher level of H3K27me3.