scholarly journals FOXR2 Stabilizes MYCN Protein and Identifies Non–MYCN-Amplified Neuroblastoma Patients With Unfavorable Outcome

2021 ◽  
pp. JCO.20.02540
Author(s):  
Felix Schmitt-Hoffner ◽  
Sjoerd van Rijn ◽  
Umut H. Toprak ◽  
Monika Mauermann ◽  
Felix Rosemann ◽  
...  

PURPOSE Clinical outcomes of patients with neuroblastoma range from spontaneous tumor regression to fatality. Hence, understanding the mechanisms that cause tumor progression is crucial for the treatment of patients. In this study, we show that FOXR2 activation identifies a subset of neuroblastoma tumors with unfavorable outcome and we investigate the mechanism how FOXR2 relates to poor outcome in patients. MATERIALS AND METHODS We analyzed three independent transcriptional data sets of in total 1030 primary neuroblastomas with full clinical annotation. We performed immunoprecipitation for FOXR2 and MYCN and silenced FOXR2 expression in two neuroblastoma cell lines to examine the effect on cellular processes, transcriptome, and MYCN protein levels. Tumor samples were analyzed for protein levels of FOXR2 and MYCN. RESULTS In three combined neuroblastoma data sets, 9% of tumors show expression of FOXR2 but have low levels of MYCN mRNA. FOXR2 expression identifies a group of patients with unfavorable outcome, showing 10-year overall survival rates of 53%-59%, and proves to be an independent prognostic factor compared with established risk factors. Transcriptionally, FOXR2-expressing tumors are very similar to MYCN-amplified tumors, suggesting that they might share a common mechanism of tumor initiation. FOXR2 knockdown in FOXR2-expressing neuroblastoma cell lines resulted in cell cycle arrest, reduced cell growth, cell death, and reduced MYCN protein levels, all indicating that FOXR2 is essential for these tumors. Finally, we show that FOXR2 binds and stabilizes MYCN protein and MYCN protein levels are highly increased in FOXR2-expressing tumors, in several cases comparable with MYCN-amplified samples. CONCLUSION The stabilization of MYCN by FOXR2 represents an alternative mechanism to MYCN amplification to increase MYCN protein levels. As such, FOXR2 expression identifies another subset of neuroblastoma patients with unfavorable clinical outcome.

2020 ◽  
Vol 19 ◽  
pp. 153303382095762
Author(s):  
Li Zhang ◽  
Hangyu Zhou ◽  
Jing Li ◽  
Xinyu Wang ◽  
Xin Zhang ◽  
...  

Neuroblastoma (NB) is a rare type of cancer but frequently occurred in children. However, it is still unclear whether circular RNAs (circRNAs) play key roles in NB tumorigenesis or progression. In this study, we identified 39,022 circRNAs across the 39 neuroblastoma and 2 normal cell lines. With the gene and circRNA expression data, we classified the NB cell lines, identified and characterized the functional circRNAs in the 3 NB classes. Specifically, 29 circRNAs were found to be dysregulated in the NB classes. Notably, 7 circRNAs located within MYCN-amplified regions were upregulated in cell lines with the high activities of MYC targets and MYCN amplification, and were highly correlated with expression of their parental gene, NBAS. Subsequently, we constructed ceRNA networks for the functional circRNAs. Specifically, hsa_circ_0005379 was identified as a critical regulator in the ceRNA networks because of targeting 13 genes, which formed a complex competing endogenous RNA (ceRNA) network. Moreover, hsa_circ_0002343, which was connected with few genes, might regulate the PI3K/Akt/mTOR signaling via RAC1. Furthermore, 3 genes, including NOTCH2, SERPINH1, and LAMC1, involved in epithelial mesenchymal transition (EMT) were observed to connect with hsa_circ_0001361, suggesting that this circRNA was closely associated with EMT. Consequently, 7 genes, such as DAD1, PPIA, NOTCH2, PGK1, BUB1, EIF2S1, and TCF7L2, were found to be closely associated with both event-free survival (EFS) and overall survival (OS). In conclusion, the present study identified functional circRNAs and predicted their functionality in neuroblastoma cell lines, which not only improved the understanding of circRNAs in neuroblastoma, but also provided the evidences for the related researchers.


2019 ◽  
Vol 39 (1) ◽  
Author(s):  
Gang Chen ◽  
Weicheng Chen ◽  
Ming Ye ◽  
Weiqiang Tan ◽  
Bing Jia

Abstract Neuroblastoma is the most common tumor in children, with a very poor prognosis. It is urgent to identify novel biomarkers to treat neuroblastoma, together with surgery, chemotherapy, and radiation. Human tripartite motif 59 (TRIM59), a member of the TRIM family, has been reported to participate in several human tumors. However, the exact role of TRIM59 in neuroblastoma is unknown. In the present study, real-time PCR and Western blot were used to measure mRNA and protein levels of TRIM59 in four neuroblastoma cell lines and in neuroblastoma tissues. Lentiviruses targeting TRIM59 were used to up/down-regulate TRIM59 expression levels. Cell Counting Kit-8 and Annexin-V/PI were used to analyze cell proliferation and apoptosis in neuroblastoma cell lines. Our data showed that TRIM59 knockdown inhibits cell proliferation while inducing apoptosis in SH-SY5Y and SK-N-SH neuroblastoma cell lines. TRIM59 knockdown up-regulated expression of Bax and Bim and down-regulated levels of Survivin, β-catenin, and c-myc. Interestingly, the inhibition of cell proliferation caused by TRIM59 knockdown could be blocked by LiCl, which is an agonist of Wnt/β-catenin signaling pathway. In contrast, TRIM59 overexpression could increase cell proliferation, up-regulate Survivin, β-catenin and c-myc, down-regulate Bax and Bim, and these effects could be blocked by XAV939, which is an inhibitor of Wnt/β-catenin signaling pathway. In addition, TRIM59 was up-regulated and positively related with β-catenin in neuroblastoma tissues. In conclusion, TRIM59 was up-regulated in neuroblastoma, and TRIM59 knockdown inhibited cell proliferation by down-regulating the Wnt/β-catenin signaling pathway in neuroblastoma.


2010 ◽  
Vol 222 (03) ◽  
Author(s):  
S Degen ◽  
S Kuhfittig-Kulle ◽  
JH Schulte ◽  
F Westermann ◽  
A Schramm ◽  
...  

Gene ◽  
2004 ◽  
Vol 337 ◽  
pp. 91-103 ◽  
Author(s):  
Hidehiko Sugino ◽  
Tomoko Toyama ◽  
Yusuke Taguchi ◽  
Shigeyuki Esumi ◽  
Mitsuhiro Miyazaki ◽  
...  

2021 ◽  
Vol 22 (12) ◽  
pp. 6565
Author(s):  
Jennifer H. Foster ◽  
Eveline Barbieri ◽  
Linna Zhang ◽  
Kathleen A. Scorsone ◽  
Myrthala Moreno-Smith ◽  
...  

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.


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