Regulation of the EphA2 Tyrosine Phosphorylation by the Human Cytoplasmic Protein Tyrosine Phosphatase

Abstract

Intracellular signaling by protein tyrosine phosphorylation is generally understood to govern many aspects of cellular behavior. The biological consequences of this signaling pathway are important because the levels of protein tyrosine phosphorylation are frequently elevated in cancer cells. In the classic paradigm, tyrosine kinases promote tumor cell growth, survival and invasiveness whereas tyrosine phosphatases negatively regulate these same behaviors. Here, we identify one particular tyrosine phosphatase, LMW-PTP, which is frequently overexpressed in transformed cells. We also show that overexpression of LMW-PTP is sufficient to confer malignant transformation upon non-transformed mammary epithelial cells. Notably, we show that the EphA2 receptor tyrosine kinase is a prominent substrate for LMW-PTP and that the oncogenic activities of LMW-PTP result from altered EphA2 expression and function. These results suggest a role for LMW-PTP in breast cancer progression and link its oncogenic potential to EphA2.

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Document Details

Document Type
Technical Report
Publication Date
Jun 01, 2002
Accession Number
ADB282209

Entities

People

  • Elikplimi K. Asem

Organizations

  • Purdue University

Tags

DTIC Thesaurus Topics

  • Antisense Elements (Genetics)
  • Biomedical Research
  • Breast Cancer
  • Cell Line
  • Cells
  • Chemical Synthesis
  • Chemistry
  • Epithelial Cells
  • Governments
  • Kinases
  • Materials
  • Neoplasms
  • Phosphorylation
  • Regulations
  • Substrates
  • Survival
  • Tyrosine

Fields of Study

  • Biology

Readers

  • Breast cancer cell signaling and growth regulation.