The Anti-Tumor Activity of the NEDD8 Inhibitor Pevonedistat in Neuroblastoma.

Jennifer H Foster,Myrthala Moreno-Smith,Terzah M Horton,Kathleen A Scorsone,Eveline Barbieri,Peter Zage,Linna Zhang

doi:10.3390/ijms22126565

Abstract

Pevonedistat is a neddylation inhibitor that blocks proteasomal degradation of cullin–RING ligase (CRL) proteins involved in the degradation of short-lived regulatory proteins, including those involved with cell-cycle regulation. We determined the sensitivity and mechanism of action of pevonedistat cytotoxicity in neuroblastoma. Pevonedistat cytotoxicity was assessed using cell viability assays and apoptosis. We examined mechanisms of action using flow cytometry, bromodeoxyuridine (BrDU) and immunoblots. Orthotopic mouse xenografts of human neuroblastoma were generated to assess in vivo anti-tumor activity. Neuroblastoma cell lines were very sensitive to pevonedistat (IC50 136–400 nM). The mechanism of pevonedistat cytotoxicity depended on p53 status. Neuroblastoma cells with mutant (p53MUT) or reduced levels of wild-type p53 (p53si-p53) underwent G2-M cell-cycle arrest with rereplication, whereas p53 wild-type (p53WT) cell lines underwent G0-G1 cell-cycle arrest and apoptosis. In orthotopic neuroblastoma models, pevonedistat decreased tumor weight independent of p53 status. Control mice had an average tumor weight of 1.6 mg + 0.8 mg versus 0.5 mg + 0.4 mg (p < 0.05) in mice treated with pevonedistat. The mechanism of action of pevonedistat in neuroblastoma cell lines in vitro appears p53 dependent. However, in vivo studies using mouse neuroblastoma orthotopic models showed a significant decrease in tumor weight following pevonedistat treatment independent of the p53 status. Novel chemotherapy agents, such as the NEDD8-activating enzyme (NAE) inhibitor pevonedistat, deserve further study in the treatment of neuroblastoma.

Highlights

Introduction published maps and institutional affilNeddylation is an ATP-dependent process which is involved in the regulation of intracellular protein destruction
Using a panel of neuroblastoma cell lines that differ in MYCN and p53 status, we showed that pevonedistat was cytotoxic in vitro at nanomolar concentrations (Figure 1)
Both p53 mutant (p53MUT ) and p53 wild type (p53WT ) neuroblastoma cell lines were sensitive to pevonedistat, and sensitivity did not vary by MYCN status (Figure 1)

Summary

Introduction

Neddylation is an ATP-dependent process which is involved in the regulation of intracellular protein destruction. Similar to the process of ubiquitination, neddylation is controlled by a multistep process involving three enzymes: a single activation enzyme (E1) known as the NEDD8-activating enzyme (NAE), several NEDD conjugating enzymes (E2) which bring NEDD8 to the targeted substrate protein, and many NEDD8/ubiquitin ligases (E3) which transfer and ligate NEDD8 to the targeted substrate. Recent studies have shown that inhibition of the E1-NAE disrupts cancer cell proliferation by interfering with cullin–RING ligase (CRL) mediated neddylation and subsequent ubiquitination [1,2,3,4]. Cullin–RING ligases (E3), the largest complex of ring ligases, are responsible for the timed degradation of many proteins involved in the cell cycle, including WEE1, Crlf, Ets and I-κB. CRLs play an essential role in targeting proteins for ubiquitin-mediated destruction.

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Results

Conclusion