EZH2 and breast cancer: To expand the investigation of EZH2’s effect on bone metastasis, we also established CRISPR/CAS9-mediated EZH2-knockout subclones in 4T1 mouse mammary tumor cells (4T1.KO #1 and #2) (Supplementary Fig. 1o) and examined their proliferation, migration, and invasion compared with those of the control 4T1 cells.