Anti-proliferative and apoptosis-inducing effects of juglone in LS-174T cells were investigated. In this study, we showed that juglone inhibited the proliferation of LS-174T cells in a time and dose-dependent manner, treatment of juglone resulted in the activation of caspase-9 and caspase-3, decrease of Bcl-2. N-acetylcysteine significantly attenuate LS-174T cell death induced by juglone (p