Notably, since the importance of BCKDK translocation to the nucleus was proven (Figure 1), we closely examined nuclear‐localized BCKDK in these clinical patient samples and found a large proportion of tumor samples exhibited strong nuclear BCKDK staining in contrast to adjacent normal tissues (Figure 5e), further demonstrating that nuclear‐localized BCKDK is associated with breast cancer progression. This evidence concerns the gene BCKDK and breast cancer.