Gene amplifications in well-differentiated pancreatic neuroendocrine Tumors inactivate the p53 Pathway Journal Article


Authors: Hu, W.; Feng, Z.; Modica, I.; Klimstra, D. S.; Song, L.; Allen, P. J.; Brennan, M. F.; Levine, A. J.; Tang, L. H.
Article Title: Gene amplifications in well-differentiated pancreatic neuroendocrine Tumors inactivate the p53 Pathway
Abstract: Neuroendocrine tumors (NETs) comprise a group of rare tumors derived from the diffuse neuroendocrine system or islet endocrine cells of the pancreas. The molecular mechanisms underlying NETs are largely unknown. The tumor suppressor p53 plays a critical role in maintaining genomic stability and tumor prevention. The p53 pathway is tightly regulated by a number of proteins, among which MDM2, MDM4, and WIP1 are key negative regulators of p53 protein levels or activity. Aberrant activation of these negative regulators can attenuate the p53 function that serves as an important mechanism of tumorigenesis. In this study, several genetic alterations in pancreatic NETs were studied. These tumors exhibit various chromosomal aberrations throughout the whole genome as examined by array-based comparative genomic hybridization. Although p53 mutations are rare in NETs (<3%), this study presents evidence that the p53 pathway is altered in pancreatic NETs through aberrant activation of its negative regulators. A high percentage of pancreatic NETs contain extra gene copies of MDM2 (22%), MDM4 (30%), and WIP1 (51%), which are correlated with expression of corresponding mRNAs and proteins. In addition, there is a higher frequency (23% v. 15% in the control population) of the G/G genotype of MDM2 SNP309, a functional single-nucleotide polymorphism in the MDM2 gene that attenuates the function of the p53 protein. Overall, approximately 70% of pancreatic NETs have one or more of these genetic changes. These findings suggest that the negative regulation of p53 function could be an important echanism for the initiation and/or progression of pancreatic NETs, and reactivation of p53 could be a potential therapeutic strategy for patients with this disease. © The Author(s) 2010.
Keywords: neuroendocrine tumor; p53; mdm2; mdm4; wip1
Journal Title: Genes and Cancer
Volume: 1
Issue: 4
ISSN: 1947-6019
Publisher: Sage Publications  
Date Published: 2010-05-15
Start Page: 360
End Page: 368
Language: English
DOI: 10.1177/1947601910371979
PROVIDER: scopus
PMCID: PMC2943645
PUBMED: 20871795
DOI/URL:
Notes: --- - "Cited By (since 1996): 2" - "Export Date: 20 April 2011" - "Source: Scopus"
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MSK Authors
  1. Murray F Brennan
    1059 Brennan
  2. David S Klimstra
    978 Klimstra
  3. Peter Allen
    501 Allen
  4. Laura Hong Tang
    447 Tang
  5. Ippolito Modica
    11 Modica
  6. Lin Song
    10 Song