The Nedd8-activating enzyme inhibitor MLN4924 suppresses colon cancer cell growth via triggering autophagy

Neddylation is a post-translational protein modification process. MLN4924 is a newly discovered pharmaceutical neddylation inhibitor that suppresses cancer growth with several cancer types. In our study, we first investigated the effect of MLN4924 on colon cancer cells (HCT116 and HT29). MLN4924 significantly inhibited the neddylation of cullin-1 and colon cancer cell growth in a time and dose-dependent manner. MLN4924 induced G2/M cell cycle arrest and apoptosis in HCT116 and HT29 cells. Moreover, MLN4924 also triggered autophagy in HCT116 and HT29 cells via suppressing the PI3K/AKT/mTOR pathway. Inhibiting autophagy by autophagy inhibitor 3-MA or ATG5 knockdown reversed the function of MLN4924 in suppressing colon cancer cell growth and cell death. Interestingly, MLN4924 suppresses colon cell growth in a xenograft model. Together, our finding revealed that blocking neddylation is an attractive colon cancer therapy strategy, and autophagy might act as a novel anti-cancer mechanism for the treatment of colon cancer by MLN4924.

Effect of salvianolic acid B and tanshinone Ⅱ A on theproliferation of rat thoracic aorta adventitial fibroblast / 中国药理学通报

Aim To explore the effects of salvianolic acid B(SAB) and tanshinone ⅡA(TA) alone or the compatibility of these two effective components on the proliferation of rat vascular adventitial fibroblasts, and to observe the effects of the compatibility of the two on cell proliferation with the stimuation of angiotensin Ⅱ(Ang Ⅱ).Methods The effects of SAB and TA alone or the compatibility of the two on cell proliferation were detected by methyl thiazolyl tetrazolium(MTT) method, and flow cytometry was adopted to detect cell cycle with or without the induction of Ang Ⅱ.Results It was shown that SAB and TA alone could inhibit fibroblast proliferation in different degree.Through a series of concentration screening, three effective concentrations were obtained respectively and then the inhibition of cell growth was detected by Pairwise compatibilities.The results showed that the compatibility of TA(10-8 mol·L-1) and SAB(10-5 mol·L-1) had the most significant inhibitory effect(P<0.01), and they could inhibit cell proliferation, further flow cytometry was adopted to detect drug effects on cell cycle, the results indicated that the compatibility of SAB and TA mainly blocked the cells in G0/G1 phase.Induced by Ang Ⅱ, the compatibility of SAB and TA group, compared with Ang Ⅱ group, blocked thee cells in G0/G1 phase;and compared with combination of SAB and TA group, it mainly blocked cell cycle in S phase.Conclusion SAB and TA have certain inhibitory effect on fibroblast proliferation, also they could inhibit the proliferation induced by Ang Ⅱ, mainly by blocking the cells in G0/G1 phase.