Display Settings:

Format

Send to:

Choose Destination
See comment in PubMed Commons below
Exp Cell Res. 2007 Sep 10;313(15):3337-48. Epub 2007 Jun 29.

Synergistic up-regulation of Hexokinase-2, glucose transporters and angiogenic factors in pancreatic cancer cells by glucose deprivation and hypoxia.

Author information

  • 1Department of Pathological Oncology, Division of Cancer Medicine, Hokkaido University Graduate School of Medicine, Japan.

Abstract

There is accumulating evidence demonstrating that HIF-1 functions as a key regulator of the adaptation responses to hypoxia in cancer tissues. To this evidence, we add that adaptation responses to glucose deprivation plus hypoxia are also necessary for the survival of tumor cells in the tumor microenvironment as cancer tissues are exposed to glucose deprivation as well as hypoxia. We found that adrenomedullin (AM), VEGF, Glut-1, Glut-3, and Hexokinase-2 among 45 hypoxia-inducible genes investigated were expressed at higher levels under glucose-deprived hypoxic conditions than under hypoxic conditions. Glucose deprivation activated the AMPK under normoxia and hypoxia. Compound C, an inhibitor of AMPK, suppressed the expressions of AM and VEGF which had already been enhanced under glucose-deprived hypoxic conditions. siRNAs for both AMPKalpha1 and AMPKalpha2 suppressed the expressions of AM and VEGF. HIF-1alpha protein level and the transcriptional activity of HIF-1 under glucose-deprived hypoxic conditions were thus found to be similar to those under hypoxic conditions. Furthermore, tumor cells in 15 out of 20 human pancreatic cancer tissue specimens were stained by anti-phospho-AMPKalpha antibody. Our results thus suggest that the enhanced expressions of those genes mediated by the activation of AMPK and HIF-1 therefore play a pivotal role in the tumor formation of pancreatic cancers.

PMID:
17651733
[PubMed - indexed for MEDLINE]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science
    Loading ...
    Write to the Help Desk