PHD3 regulates differentiation, tumour growth and angiogenesis in pancreatic cancer

Br J Cancer. 2010 Nov 9;103(10):1571-9. doi: 10.1038/sj.bjc.6605936. Epub 2010 Oct 26.

Abstract

Purpose: Tumour hypoxia activates hypoxia-inducible factor-1 (HIF-1) and indluences angiogenesis, cell survival and invasion. Prolyl hydroxylase-3 (PHD3) regulates degradation of HIF-1α. The effects of PHD3 in tumour growth are largely unknown.

Experimental design: PHD3 expression was analysed in human pancreatic cancer tissues and cancer cell lines by real-time quantitative PCR and immunohistochemistry. PHD3 overexpression was established by stable transfection and downregulation by short interfering RNA technology. VEGF was quantified by enzyme-linked immunosorbent assay. Matrigel invasion assays were performed to examine tumour cell invasion. Apoptosis was measured by annexin-V staining and caspase-3 assays. The effect of PHD3 on tumour growth in vivo was evaluated in an established orthotopic murine model.

Results: PHD3 was upregulated in well-differentiated human tumours and cell lines, and regulated hypoxic VEGF secretion. PHD3 overexpression mediated tumour cell growth and invasion by induction of apoptosis in a nerve growth factor-dependent manner by the activation of caspase-3 and phosphorylation of focal adhesion kinase HIF-1 independently. In vivo, PHD3 inhibited tumour growth by abrogation of tumour angiogenesis.

Conclusion: Our results indicate essential functions of PHD3 in tumour growth, apoptosis and angiogenesis and through HIF-1-dependent and HIF-1-independent pathways.

MeSH terms

  • Adenocarcinoma / pathology
  • Adenocarcinoma / surgery
  • Animals
  • Annexin A5 / analysis
  • Apoptosis
  • Carcinoma, Pancreatic Ductal / enzymology
  • Carcinoma, Pancreatic Ductal / pathology
  • Carcinoma, Pancreatic Ductal / surgery
  • Caspase 3 / metabolism
  • Cell Differentiation
  • Cell Line, Tumor
  • Dioxygenases / genetics*
  • Dioxygenases / physiology
  • Enzyme-Linked Immunosorbent Assay
  • Humans
  • Hypoxia-Inducible Factor 1, alpha Subunit / genetics
  • Hypoxia-Inducible Factor 1, alpha Subunit / physiology
  • Hypoxia-Inducible Factor-Proline Dioxygenases
  • Mice
  • Neoplasm Invasiveness / genetics
  • Neoplasm Invasiveness / pathology
  • Neovascularization, Pathologic / pathology*
  • Pancreatic Neoplasms / enzymology
  • Pancreatic Neoplasms / pathology*
  • Pancreatic Neoplasms / surgery
  • Polymerase Chain Reaction
  • RNA, Messenger / genetics
  • RNA, Neoplasm / genetics
  • Reverse Transcriptase Polymerase Chain Reaction
  • Transplantation, Heterologous
  • Up-Regulation
  • Vascular Endothelial Growth Factor A / analysis

Substances

  • Annexin A5
  • HIF1A protein, human
  • Hypoxia-Inducible Factor 1, alpha Subunit
  • RNA, Messenger
  • RNA, Neoplasm
  • Vascular Endothelial Growth Factor A
  • Dioxygenases
  • EGLN3 protein, human
  • Hypoxia-Inducible Factor-Proline Dioxygenases
  • Caspase 3