CUL4B and cancer: The chemotactic migration assay and cancer cell–bone matrix adhesion assay indicated that depletion of RUNX2, MTA1, or CUL4B hampered breast cancer cell metastasis to the bone, while overexpression of RUNX2, MTA1, or CUL4B resulted in the opposite trend (Fig. 3K, L, Supplementary Fig. 3I, J).