ESR2 and Familial prostate cancer: On the other hand, this phytoestrogen has been reported to exert its antitumor activity in breast and prostate cancer cells through activation of ERβ (180); interestingly, in prostate cancer cells, apigenin induces apoptosis by selectively inhibiting proteasomal activity, thus rescuing ERβ from degradation and, therefore, increasing its intracellular levels (188).