Role of hypoxia-inducible factor 1α in gastric cancer cell growth, angiogenesis, and vessel maturation

Oliver Stoeltzing, Marya F. McCarty, Jane S. Wey, Fan Fan, Wenbiao Liu, Anna Belcheva, Corazon D. Bucana, Gregg L. Semenza, Lee M. Ellis

Research output: Contribution to journalArticlepeer-review

Abstract

Background: Hypoxia-inducible factor 1 (HIF-1), a heterodimer comprising the oxygen-regulated subunit, HIF-1α, and HIF-1β, mediates transcription of the gene for vascular endothelial growth factor (VEGF). Overexpression of HIF-1α is associated with tumor angiogenesis and tumor cell proliferation and invasion. We examined the effects of inhibiting HIF-1α activity on angiogenesis and human gastric cancer growth in vivo. Methods: Human gastric cancer TMK-1 cells were stably transfected with pHIF-1αDN, an expression plasmid encoding a dominant-negative form of HIF-1α that dimerizes with endogenous HIF-1β to produce HIF-1 complexes that cannot activate transcription, or with the empty expression vector (pCEP4). Two clones of pHIF-1αDN-transfected cells, DN2 and DN3, were tested in all experiments. We used an enzyme-linked immunosorbent assay to measure VEGF secretion by transfected cells cultured in hypoxic (1% O2) or nonhypoxic (20% O2) conditions. We used subcutaneous and orthotopic mouse tumor models to examine the growth of tumors derived from injected pHIF-1αDN- or pCEP4-transfected cells. Tumor cell proliferation, vessel area (a measure of functional vascular volume), and tumor endothelial cell association with pericyte-like cells (a measure of vessel maturation) were analyzed by immunohistochemical or immunofluorescent staining. All statistical tests were two-sided. Results: DN2 cells and DN3 cells secreted less VEGF than pCEP4-transfected TMK-1 cells when cultured in nonhypoxic or hypoxic conditions (e.g., DN2 versus pCEP4 in nonhypoxic conditions: 645 pg of VEGF/106 cells versus 1591 pg of VEGF/106 cells, difference = 946 pg of VEGF/106 cells [95% confidence interval {CI} = 640 to 1251 pg of VEGF/106 cells; P = .006]; DN2 versus pCEP4 in hypoxic conditions: 785 pg of VEGF/106 cells versus 2807 pg of VEGF/106 cells, difference = 2022 pg of VEGF/106 cells [95% CI = 1871 to 2152 pg of VEGF/106 cells; P<.001]). In the subcutaneous tumor model, tumors derived from DN2 or DN3 cells had lower final volumes, weights, and vessel areas, less tumor endothelial cell association with desmin-positive cells, and fewer proliferating tumor cells than tumors derived from pCEP4-transfected cells. In the orthotopic tumor model, tumors derived from DN2 cells had smaller volumes and less vessel area and maturation than tumors derived from pCEP4-transfected cells. Conclusions: Inhibition of HIF-1α activity impairs gastric tumor growth, angiogenesis, and vessel maturation.

Original languageEnglish (US)
Pages (from-to)946-956
Number of pages11
JournalJournal of the National Cancer Institute
Volume96
Issue number12
DOIs
StatePublished - Jun 16 2004

ASJC Scopus subject areas

  • Oncology
  • Cancer Research

Fingerprint

Dive into the research topics of 'Role of hypoxia-inducible factor 1α in gastric cancer cell growth, angiogenesis, and vessel maturation'. Together they form a unique fingerprint.

Cite this