Role of cyclophilin B in tumorigenesis and cisplatin resistance in hepatocellular carcinoma in humans

Hepatology. 2011 Nov;54(5):1661-78. doi: 10.1002/hep.24539.


Cyclophilin B (CypB) performs diverse roles in living cells, but its role in hepatocellular carcinoma (HCC) is largely unclear. To reveal its role in HCC, we investigated the induction of CypB under hypoxia and its functions in tumor cells in vitro and in vivo. Here, we demonstrated that hypoxia-inducible factor 1α (HIF-1α) induces CypB under hypoxia. Interestingly, CypB protected tumor cells, even p53-defective HCC cells, against hypoxia- and cisplatin-induced apoptosis. Furthermore, it regulated the effects of HIF-1α, including those in angiogenesis and glucose metabolism, via a positive feedback loop with HIF-1α. The tumorigenic and chemoresistant effects of CypB were confirmed in vivo using a xenograft model. Finally, we showed that CypB is overexpressed in 78% and 91% of the human HCC and colon cancer tissues, respectively, and its overexpression in these cancers reduced patient survival.

Conclusions: These results indicate that CypB induced by hypoxia stimulates the survival of HCC via a positive feedback loop with HIF-1α, indicating that CypB is a novel candidate target for developing chemotherapeutic agents against HCC and colon cancer.

MeSH terms

  • Animals
  • Antineoplastic Agents / pharmacology
  • Apoptosis / drug effects
  • Carcinoma, Hepatocellular / drug therapy*
  • Carcinoma, Hepatocellular / metabolism
  • Carcinoma, Hepatocellular / pathology*
  • Cisplatin / pharmacology*
  • Colonic Neoplasms / metabolism
  • Colonic Neoplasms / pathology
  • Cyclophilins / genetics*
  • Cyclophilins / metabolism
  • Drug Resistance, Neoplasm / physiology
  • Female
  • Hep G2 Cells
  • Humans
  • Hydrogen Peroxide / pharmacology
  • Hypoxia / pathology
  • Hypoxia-Inducible Factor 1, alpha Subunit / genetics
  • Hypoxia-Inducible Factor 1, alpha Subunit / metabolism
  • Liver Neoplasms / drug therapy*
  • Liver Neoplasms / metabolism
  • Liver Neoplasms / pathology*
  • Male
  • Mice
  • Mice, Inbred BALB C
  • Mice, Nude
  • Neovascularization, Pathologic / metabolism
  • Neovascularization, Pathologic / pathology
  • Oxidants / pharmacology
  • Promoter Regions, Genetic / physiology
  • STAT3 Transcription Factor / metabolism
  • Vascular Endothelial Growth Factor A / metabolism
  • Xenograft Model Antitumor Assays


  • Antineoplastic Agents
  • HIF1A protein, human
  • Hypoxia-Inducible Factor 1, alpha Subunit
  • Oxidants
  • STAT3 Transcription Factor
  • STAT3 protein, human
  • VEGFA protein, human
  • Vascular Endothelial Growth Factor A
  • cyclophilin B
  • Hydrogen Peroxide
  • Cyclophilins
  • Cisplatin