MLN4924

MLN4924 is a potent and selective small-molecule inhibitor of NEDD8-activating enzyme (NAE) (IC50 = 4 nM) [1,2], and is selective relative to the closely related enzymes UAE, SAE, UBA6 and ATG7 (IC50 = 1.5, 8.2, 1.8 and >10 µM, respectively) ^[2]. MLN4924 has a multifaceted mechanism of action that is characterized by the induction of DNA re-replication and DNA damage, increased oxidative stress, inhibition of NF-B activity, apoptotic cell death, and cellular senescence ^[3].

MLN4924 Treatment of HCT-116 cells for 24 h resulted in a dose-dependent decrease of Ubc12-NEDD8 thioester and NEDD8-cullin conjugates, with an IC50 < 0.1 µM ^[2], resulting in a reciprocal increase in the abundance of the known CRL substrates CDT1, p27 and NRF2 (also known as NFE2L2), c-Jun27, HIF1α, cyclin E29, CDC25A, EMI1 (also known as FBXO5) and phosphorylated IκBα, but not non-CRL substrates ^[2]. MLN4924 treatment of human-tumour-derived cell lines, including HCT-116(colon), Calu-6 (lung), SKOV-3 (ovarian), H460 (lung), DLD-1 (colon), CWR22 (prostate) and OCI-LY19 (lymphoma), resulted in S-phase-defective phenotypes ^[2]. Potent inhibition of MLN4924 of cell viability was observed across 17 lymphoma cell lines tested in an ATPlite viability assay, with EC50 values of 10 to 244nM ^[1].

In OCI-Ly10 xenografts, a dose- and time-dependent increase in pIκBα levels was observed after MLN4924 treatment (10, 30, or 60 mg/kg, subcutaneous), with peak elevation occurring 2 hours after dose and levels returning to baseline at 8 hours after dose. A consequence of inhibiting NAE and NF-κB signaling in OCI-Ly10 xenografts was the induction of apoptosis 8 to 12 hours after a single dose of 60 mg/kg MLN4924, as evidenced by detection of cleaved caspase-3 ^[1]. A single dose of MLN4924 resulted in a dose- and time-dependent decrease of NEDD8-cullin levels as early as 30 min after administration of MLN4924 (10, 30 or 60 mg/kg, subcutaneous), with maximal effect 1-2 h post-dose on HCT-116 tumour-bearing mice ^[2].

References:
[1]. Milhollen M A, Traore T, Adams-Duffy J, et al. MLN4924, a NEDD8-activating enzyme inhibitor, is active in diffuse large B-cell lymphoma models: rationale for treatment of NF-κB-dependent lymphoma[J]. Blood, The Journal of the American Society of Hematology, 2010, 116(9): 1515-1523.
[2]. Soucy T A, Smith P G, Milhollen M A, et al. An inhibitor of NEDD8-activating enzyme as a new approach to treat cancer[J]. Nature, 2009, 458(7239): 732-736.
[3]. Nawrocki S T, Griffin P, Kelly K R, et al. MLN4924: a novel first-in-class inhibitor of NEDD8-activating enzyme for cancer therapy[J]. Expert opinion on investigational drugs, 2012, 21(10): 1563-1573.