Hypoxia as a target for drug combination therapy of liver cancer

Cressida Bowyer, Andrew Lewis, Andrew Lloyd, Gary Phillips, Wendy Macfarlane

Research output: Contribution to journalArticle

Abstract

Hepatocellular carcinoma (HCC) is the third most frequentcause of cancer deaths worldwide. The standard of care for intermediate HCC is transarterial chemoembolization, which combines tumour embolization with locoregional delivery of the chemotherapeutic doxorubicin. Embolization therapies induce hypoxia, leading to the escape and proliferation of hypoxia-adapted cancer cells. The transcription factor that orchestrates responses to hypoxia is hypoxia-inducible factor 1 (HIF-1). The aim of this work is to show that targeting HIF-1 with combined drug therapy presents an opportunity for improving outcomes for HCC treatment. HepG2 cells were cultured under normoxic and hypoxic conditions exposed to doxorubicin, rapamycin and combinations thereof, and analyzed for viability and the expression of hypoxia-induced HIF-1α in response to these treatments. A pilot study was carried out to evaluate the antitumour effects of these drug combinations delivered from drug-eluting beads in vivo using an ectopic xenograft murine model of HCC. A therapeutic doxorubicin concentration that inhibits the viability of normoxic and hypoxic HepG2 cells and above which hypoxic cells are chemoresistant was identified, together with the lowest effective dose of rapamycin against normoxic and hypoxicHepG2 cells. It was shown that combinations of rapamycinand doxorubicin are more effective than doxorubicin alone. Western Blotting indicated that both doxorubicin and rapamycin inhibit hypoxia-induced accumulation of HIF-1α. Combination treatments were more effective in vivo than either treatment alone. mTOR inhibition can improve outcomes of doxorubicin treatment in HCC Anti-Cancer.
Original languageEnglish
Pages (from-to)771-780
Number of pages10
JournalAnti-Cancer Drugs
Volume28
Issue number7
DOIs
Publication statusPublished - 24 May 2017

    Fingerprint

Bibliographical note

This is an open access article distributed under the Creative Commons Attribution License 4.0 (CCBY), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. http://creativecommons.org/licenses/by/4.0/

Keywords

  • doxorubicin
  • HepG2
  • hypoxia
  • mTOR
  • rapamycin
  • transarterial chemoembolization

Cite this