The tyrosine phosphatase PTPRD is a tumor suppressor that is frequently inactivated and mutated in glioblastoma and other human cancers Academic Article uri icon

Overview

MeSH Major

  • Gene Expression Regulation, Neoplastic
  • Glioblastoma
  • Mutation
  • Neoplasms
  • Receptor-Like Protein Tyrosine Phosphatases, Class 2

abstract

  • Tyrosine phosphorylation plays a critical role in regulating cellular function and is a central feature in signaling cascades involved in oncogenesis. The regulation of tyrosine phosphorylation is coordinately controlled by kinases and phosphatases (PTPs). Whereas activation of tyrosine kinases has been shown to play vital roles in tumor development, the role of PTPs is much less well defined. Here, we show that the receptor protein tyrosine phosphatase delta (PTPRD) is frequently inactivated in glioblastoma multiforme (GBM), a deadly primary neoplasm of the brain. PTPRD is a target of deletion in GBM, often via focal intragenic loss. In GBM tumors that do not possess deletions in PTPRD, the gene is frequently subject to cancer-specific epigenetic silencing via promoter CpG island hypermethylation (37%). Sequencing of the PTPRD gene in GBM and other primary human tumors revealed that the gene is mutated in 6% of GBMs, 13% of head and neck squamous cell carcinomas, and in 9% of lung cancers. These mutations were deleterious. In total, PTPRD inactivation occurs in >50% of GBM tumors, and loss of expression predicts for poor prognosis in glioma patients. Wild-type PTPRD inhibits the growth of GBM and other tumor cells, an effect not observed with PTPRD alleles harboring cancer-specific mutations. Human astrocytes lacking PTPRD exhibited increased growth. PTPRD was found to dephosphorylate the oncoprotein STAT3. These results implicate PTPRD as a tumor suppressor on chromosome 9p that is involved in the development of GBMs and multiple human cancers.

publication date

  • June 9, 2009

Research

keywords

  • Academic Article

Identity

Language

  • eng

PubMed Central ID

  • PMC2687998

Digital Object Identifier (DOI)

  • 10.1073/pnas.0900571106

PubMed ID

  • 19478061

Additional Document Info

start page

  • 9435

end page

  • 40

volume

  • 106

number

  • 23