For example, the elevated expression level of certain proteasome subunits was found in the samples of patients with breast cancer along with higher proteasome activity.32 The overexpression of proteasome subunit S10 accompanied by an increased proteasome activity has also been reported in melanoma.33 It is noteworthy, that the application of a proteasome inhibitor suppresses the transactivation of the androgen receptor (AR) in an androgen‐dependent manner in prostate cancer LNCaP and PC3 cell lines. Here, AR is linked to breast cancer.