Pevonedistat (MLN4924)

Description

MLN4924 is a small molecule inhibitor of Nedd8 activating enzyme (NAE) with IC50 of 4 nM.

Features

A mechanism-based inhibitor of NAE, and creates a covalent NEDD8-MLN4924 adduct catalyzed by the enzyme.

In vitro

MLN4924 is structurally related to adenosine 59-monophosphate (AMP)—a tight binding product of the NAE reaction. MLN4924 (3 μM) selectively inhibits NAE in HCT-116 cell lysates. MLN4924 (3 μM) inhibits overall protein turnover by <9% in HCT-116 cells. MLN4924 results in a dose-dependent decrease of Ubc12–NEDD8 thioester and NEDD8–cullin conjugates with an IC50 < 0.1 μM in HCT-116 cells, resulting in a reciprocal increase in the abundance of the known CRL substrates CDT1, p27 and NRF2, but not non-CRL substrates. MLN4924 (3 μM) leads cells to accumulate in S-phase as early as 8 hours and results in a significant fraction of cells contained 4N DNA content by 24 hours in HCT-116 cells. [1] MLN4924 (3 μM) results in rapid accumulation of pIkappaBalpha, decrease in nuclear p65 content, reduction of nuclear factor-kappaB (NF-kappaB) transcriptional activity, and G(1) arrest, ultimately resulting in apoptosis induction, events consistent with potent NF-kappaB pathway inhibition in ABC DLBCL cells. [2] MLN4924 (1 μM) triggers DNA replication and inhibit cell proliferation by stabilizing the DNA replication factor Cdt1, a substrate of cullins 1 and 4. MLN4924 (1 μM) , which is sufficient to elevate Cdt1 for 4-5 hours, is found to be sufficient to induce DNA replication and to activate apoptosis and senescence pathways. [3] MLN4924 treatment induces the characteristics of senescence phenotypes as evidenced by enlarged and flattened cellular morphology and positive staining of senescence-associated β-Gal. MLN4924-induced senescence is associated with cellular response to DNA damage, triggered by accumulation of DNA-licensing proteins CDT1 and ORC1, as a result of inactivation of CRL/SCF E3s. MLN4924-induced senescence is irreversible and coupled with persistent accumulation of p21 and sustained activation of DNA damage response. [4]

Cell Data

Assay

In vivo

MLN4924 (60 mg/kg) results in a dose- and time-dependent decrease of NEDD8–cullin levels as early as 30 min after administration in HCT-116 tumour-bearing mice, with maximal effect 1–2 hours post-dose. MLN4924 (60 mg/kg) also leads to a dose- and time-dependent increase in the steady state levels of NRF2 and CDT1 in HCT-116 tumour-bearing mice. MLN4924 (60 mg/kg) leads to DNA damage in the tumour indicated by the increased levels of phosphorylated CHK1 in HCT-116 tumour-bearing mice. MLN4924 administered on a BID schedule at 30 mg/kg and 60 mg/kg inhibits tumour growth with T/C values of 0.36 and 0.15, respectively, in mice bearing HCT-116 xenografts. [1] MLN4924 (60 mg/kg) blocks NAE pathway biomarkers and results in complete tumor growth inhibition in mice bearing human xenograft tumors of ABC- and GCB-DLBCL. MLN4924 (60 mg/kg) results in NF-kappaB pathway inhibition accompanied by tumor regressions in primary human tumor mice models of ABC-DLBCL. [2]