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Phosphorylated KDR can be located in the nucleus of neoplastic cells

Cristina Blazquez1, Nathan Cook, Kingsley Micklem

  • 1Departamento de Bioquimica y Biologia Molecular I, Facultad de Biologia, Universidad Complutense de Madrid, Ciudad Universitaria, Madrid 28040, Espania, Spain.

Cell Research
|February 10, 2006
PubMed

Insights

Kinase insert domain receptor (KDR) nuclear translocation occurs in human cells. Its nuclear levels, particularly phosphorylated KDR, are influenced by hypoxia and VEGF, but its function remains unclear.

Area of Science:

  • Oncology
  • Cell Biology
  • Molecular Biology

Background:

  • Kinase insert domain receptor (KDR) phosphorylation is crucial for cell proliferation and survival.
  • The mechanisms of KDR nuclear communication after activation are not fully understood.
  • Previous studies showed KDR nuclear translocation in animal cell lines upon VEGF stimulation.

Purpose of the Study:

  • To investigate KDR nuclear translocation in human cells, both in vitro and in vivo.
  • To determine the effects of hypoxia and VEGF on KDR nuclear localization in human neoplastic cells.

Main Methods:

  • Laser scanning confocal microscopy was employed.
  • Human neoplastic cell lines and tumor samples were analyzed.
  • Cells were subjected to hypoxic and VEGF stimulation.

Main Results:

  • Variable nuclear localization of total and phosphorylated KDR was observed in human cell lines and tumor samples.
  • Hypoxic stimulation increased nuclear KDR, particularly the total form, in human neoplastic cells.
  • Combined hypoxia and VEGF stimulation led to comparable increases in nuclear phosphorylated and total KDR.

Conclusions:

  • Neoplastic cells exhibit variable nuclear expression of total and phosphorylated KDR.
  • The functional significance of KDR's nuclear localization requires further investigation.

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