Our previous studies demonstrated that SFN-Cys acted as a chemopreventive agent through activating ERK1/2 in human prostate cancer DU145 and PC3 cells, a few downstream effectors were involved.24 However, the linkage between ERK1/2 phosphorylation and the modulation of maspin on cell apoptosis has not been reported yet. Here, SERPINB5 is linked to prostate cancer.