HIF-1α induced by β-elemene protects human osteosarcoma cells from undergoing apoptosis

J Cancer Res Clin Oncol. 2012 Nov;138(11):1865-77. doi: 10.1007/s00432-012-1256-5. Epub 2012 Jun 27.

Abstract

Background: β-Elemene, isolated from more than 50 Chinese herbs and plants, has shown promising anticancer effects against a broad spectrum of tumors, such as lung, breast, prostate, cervical, colon and ovarian carcinomas (Wang et al. in Cell Mol Life Sci 62:881-893, 2005; Li et al. in Cell Mol Life Sci 62:894-904, 2005; J Pharm Pharmacol 62(8):1018-1027, 2010). But it has not reported in osteosarcoma cells. The aim of the present study is to investigate the antitumor effect of β-elemene on human osteosarcoma cancer cells and the molecular mechanism involved.

Results: β-Elemene inhibited the viability of human osteosarcoma cells in a dose-time-dependent manner. The suppression of cell viability was due to the induction of apoptosis. Our study also found that β-elemene treatment upregulated HIF-1α protein, which partially inhibits apoptosis. Knockdown of HIF-1α with small interfering RNA or co-treatment with the HIF-1α inhibitor YC-1 significantly enhanced the antitumor effects of β-elemene.

Conclusions: Our study first found that β-elemene could increase the expression of HIF-1α through ROS and PI3K/Akt/mTor signaling pathway. And HIF-1α partially prevents human osteosarcoma cells from undergoing apoptosis. The anticancer effects of β-elemene was weakened by HIF-1α. So, we recognize that a combination of β-elemene with HIF-1α inhibitor might be a useful therapeutic option for osteosarcoma.

MeSH terms

  • Apoptosis / drug effects*
  • Blotting, Western
  • Cell Line, Tumor
  • Cell Proliferation / drug effects
  • Cell Survival / drug effects
  • Chromones / pharmacology
  • Dose-Response Relationship, Drug
  • Drugs, Chinese Herbal / pharmacology*
  • Enzyme Inhibitors / pharmacology
  • Humans
  • Hypoxia-Inducible Factor 1, alpha Subunit / antagonists & inhibitors
  • Hypoxia-Inducible Factor 1, alpha Subunit / genetics
  • Hypoxia-Inducible Factor 1, alpha Subunit / metabolism*
  • Indazoles / pharmacology
  • Microscopy, Fluorescence
  • Morpholines / pharmacology
  • Osteosarcoma / genetics
  • Osteosarcoma / metabolism
  • Osteosarcoma / pathology
  • Phosphatidylinositol 3-Kinases / metabolism
  • Phosphoinositide-3 Kinase Inhibitors
  • Proto-Oncogene Proteins c-akt / metabolism
  • RNA Interference
  • Reactive Oxygen Species / metabolism
  • Sesquiterpenes / pharmacology*
  • Signal Transduction / drug effects
  • TOR Serine-Threonine Kinases / metabolism
  • Time Factors

Substances

  • Chromones
  • Drugs, Chinese Herbal
  • Enzyme Inhibitors
  • Hypoxia-Inducible Factor 1, alpha Subunit
  • Indazoles
  • Morpholines
  • Phosphoinositide-3 Kinase Inhibitors
  • Reactive Oxygen Species
  • Sesquiterpenes
  • beta-elemene
  • 3-(5'-hydroxymethyl-2'-furyl)-1-benzylindazole
  • 2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one
  • MTOR protein, human
  • Proto-Oncogene Proteins c-akt
  • TOR Serine-Threonine Kinases