CBS9106-induced CRM1 degradation is mediated by cullin ring ligase activity and the neddylation pathway.

Abstract

Chromosome region maintenance 1 (CRM1) mediates the nuclear export of proteins and mRNAs, and is overexpressed in various cancers. Recent studies have also reported that CRM1 protein expression is a negative prognostic factor in patients with cancer. Therefore, CRM1 is considered a potential target for anticancer therapy. Our previous study demonstrated that CBS9106, a synthetic small-molecular inhibitor of CRM1, decreases CRM1 protein through proteasomal degradation without affecting CRM1 mRNA levels. However, the mechanism by which CRM1 is degraded is not well understood. Here, we demonstrate a novel signaling pathway that plays an important role in CBS9106-induced CRM1 degradation. We found that MLN4924, a selective inhibitor of NEDD8-activating enzyme (NAE), effectively inhibits cullin neddylation and attenuates CBS9106-induced CRM1 degradation in a time- and dose-dependent manner. MLN4924 also attenuated CBS9106-induced nuclear accumulation of Ran-binding protein 1 (RanBP1), cell growth inhibition, and apoptosis. Furthermore, RNAi-mediated knockdown of neddylation pathway proteins (NEDD8 and UBA3) or cullin ring ligase (CRL) component protein (Rbx1) attenuated CRM1 protein degradation and G1 phase cell-cycle arrest by CBS9106. Knockdown of CSN5 or CAND1 also partially inhibited CBS9106-induced CRM1 degradation. These findings demonstrate that CBS9106-induced CRM1 degradation is conferred by CRL activity involving the neddylation pathway, and that this response to CBS9106 leads to cell growth inhibition and apoptosis.

• Authors: Naoya Saito, Keiichi Sakakibara, Takuji Sato, Jonathan M Friedman, Donald W Kufe, Daniel D VonHoff, Takumi Kawabe
• Journal: Molecular cancer therapeutics (Mol Cancer Ther) Vol. 13 Issue 12 Pg. 3013-23 (Dec 2014) ISSN: 1538-8514 [Electronic] United States
• PMID: 25253782 (Publication Type: Journal Article)
• Copyright: ©2014 American Association for Cancer Research.

Chemical References

• Aminopyridines
• CAND1 protein, human
• CBS 9106
• Carrier Proteins
• Cullin Proteins
• Cyclopentanes
• Intracellular Signaling Peptides and Proteins
• Karyopherins
• NEDD8 Protein
• NEDD8 protein, human
• Nuclear Proteins
• Pyrimidines
• Pyrrolidinones
• RBX1 protein, human
• Receptors, Cytoplasmic and Nuclear
• Transcription Factors
• Tumor Suppressor Protein p53
• Ubiquitins
• exportin 1 protein
• ran-binding protein 1
• Peptide Hydrolases
• COPS5 protein, human
• COP9 Signalosome Complex
• Ubiquitin-Activating Enzymes
• NAE protein, human
• pevonedistat

Topics

• Aminopyridines (pharmacology)
• Apoptosis (drug effects)
• COP9 Signalosome Complex
• Carrier Proteins (genetics, metabolism)
• Cell Cycle (drug effects)
• Cell Line, Tumor
• Cell Nucleus (metabolism)
• Cell Survival (drug effects)
• Cullin Proteins (metabolism)
• Cyclopentanes (pharmacology)
• Gene Knockdown Techniques
• HCT116 Cells
• Humans
• Intracellular Signaling Peptides and Proteins (genetics, metabolism)
• Karyopherins (metabolism)
• Lysosomes (metabolism)
• NEDD8 Protein
• Nuclear Proteins (metabolism)
• Peptide Hydrolases (genetics, metabolism)
• Protein Transport
• Proteolysis (drug effects)
• Pyrimidines (pharmacology)
• Pyrrolidinones (pharmacology)
• Receptors, Cytoplasmic and Nuclear (metabolism)
• Signal Transduction
• Transcription Factors (genetics, metabolism)
• Tumor Suppressor Protein p53 (metabolism)
• Ubiquitin-Activating Enzymes (genetics, metabolism)
• Ubiquitins (genetics, metabolism)