A cell-permeable phenylacetamide compound that is shown to upregulate p21Cip1/Waf1 and/or p27Kip1 in prostate cancer LNCaP, PC3, DU145, but not HeLa, cultures (40μM for 24 h) with a concomitant downregulation of the F-box E3 ubiquitin ligase Skp2 and a delayed G1-to-S cell cycle transition, displaying no apparent effect toward cell cycle progression or p21 and p27 levels in non-cancer human fibroblast