Adenovirus-mediated truncated Bid overexpression induced by the Cre/LoxP system promotes the cell apoptosis of CD133+ ovarian cancer stem cells

Oncol Rep. 2017 Jan;37(1):155-162. doi: 10.3892/or.2016.5263. Epub 2016 Nov 21.

Abstract

Cancer stem cells are a small subset of cancer cells that contribute to cancer progression, metastasis, chemoresistance and recurrence. CD133-positive (CD133+) ovarian cancer cells have been identified as ovarian cancer stem cells. Adenovirus-mediated gene therapy is an innovative therapeutic method for cancer treatment. In the present study, we aimed to develop a new gene therapy to specifically eliminate CD133+ ovarian cancer stem cells by targeting CD133. We used the Cre/LoxP system to augment the selective expression of the truncated Bid (tBid) gene as suicide gene therapy in CD133+ ovarian cancer stem cells. The adenovirus (Ad)-CD133-Cre expressing Cre recombinase under the control of the CD133 promoter and Ad-CMV-LoxP-Neo-LoxP-tBid expressing tBid under the control of the CMV promoter were successfully constructed using the Cre/LoxP switching system. The co-infection of Ad-CMV-LoxP-Neo-LoxP-tBid and Ad-CD133-Cre selectively induced tBid overexpression, which inhibited cell growth and triggered the cell apoptosis of CD133+ ovarian cancer stem cells. The Cre/LoxP system-mediated tBid overexpression activated the pro-apoptotic signaling pathway and augmented the cytotoxic effect of cisplatin in CD133+ ovarian cancer stem cells. Furthermore, in xenograft experiments, co-infection with the two recombinant adenoviruses markedly suppressed tumor growth in vivo and promoted cell apoptosis in tumor tissues. Taken together, the present study provides evidence that the adenovirus-mediated tBid overexpression induced by the Cre/LoxP system can effectively eliminate CD133+ ovarian cancer stem cells, representing a novel therapeutic strategy for the treatment of ovarian cancer.

MeSH terms

  • AC133 Antigen / metabolism
  • Adenoviridae / genetics*
  • Animals
  • Apoptosis / genetics*
  • BH3 Interacting Domain Death Agonist Protein / chemistry
  • BH3 Interacting Domain Death Agonist Protein / genetics*
  • Codon, Nonsense
  • Female
  • Gene Expression Regulation, Neoplastic
  • Gene Transfer Techniques
  • Genetic Therapy / methods*
  • Genetic Vectors
  • HEK293 Cells
  • Humans
  • Integrases / genetics*
  • Mice
  • Mice, SCID
  • Mutagenesis, Site-Directed
  • Neoplastic Stem Cells / metabolism
  • Neoplastic Stem Cells / pathology
  • Neoplastic Stem Cells / physiology*
  • Ovarian Neoplasms / genetics
  • Ovarian Neoplasms / metabolism
  • Ovarian Neoplasms / pathology
  • Ovarian Neoplasms / therapy*
  • Tumor Cells, Cultured
  • Xenograft Model Antitumor Assays

Substances

  • AC133 Antigen
  • BH3 Interacting Domain Death Agonist Protein
  • BID protein, human
  • Codon, Nonsense
  • PROM1 protein, human
  • Cre recombinase
  • Integrases