Novel REIC/Dkk-3-encoding adenoviral vector as a promising therapeutic agent for pancreatic cancer

Cancer Gene Ther. 2016 Aug;23(8):278-83. doi: 10.1038/cgt.2016.31. Epub 2016 Jul 29.

Abstract

Reduced expression in immortalized cells (REIC)/dickkopf-3 (Dkk-3), a tumor suppressor gene, is downregulated in various cancers. We previously reported the tumor-inhibitory effects of the REIC/Dkk-3 gene, delivered by a conventional adenoviral vector (Ad-CAG-REIC) in pancreatic cancer. Here, we developed an Ad-REIC vector with a novel gene expression system, termed the super gene expression (SGE) system, and assessed its therapeutic effects relative to those of Ad-CAG-REIC in pancreatic cancer cells. Human pancreatic cancer cell lines ASPC1 and MIAPaCa2 were used. REIC/Dkk-3 expression was assessed by western blot analysis. Relative cell viability and apoptotic effects were examined in vitro. The anti-tumor effects of Ad-REIC treatment were assessed in the mouse xenograft model. Compared with Ad-CAG-REIC, Ad-SGE-REIC elicited a significant increase in REIC protein expression in the cells studied. Relative to Ad-CAG-REIC, Ad-SGE-REIC reduced cell viability and induced apoptosis in the ASPC1 and MIAPaCa2 cell lines in vitro, and achieved superior tumor growth inhibition in the mouse xenograft model. Compared with conventional Ad-REIC agents, Ad-SGE-REIC provided enhanced inhibitory effects against tumor growth. Our results indicate that Ad-SGE-REIC is an innovative therapeutic tool for pancreatic cancer.

MeSH terms

  • Adaptor Proteins, Signal Transducing
  • Adenoviridae / genetics*
  • Animals
  • Apoptosis / genetics
  • Cell Line, Tumor
  • Cell Survival / genetics
  • Chemokines
  • Disease Models, Animal
  • Gene Expression
  • Gene Order
  • Genetic Therapy*
  • Genetic Vectors / administration & dosage
  • Genetic Vectors / genetics*
  • Humans
  • Intercellular Signaling Peptides and Proteins / genetics*
  • Intercellular Signaling Peptides and Proteins / metabolism
  • JNK Mitogen-Activated Protein Kinases / metabolism
  • Mice
  • Pancreatic Neoplasms / genetics*
  • Pancreatic Neoplasms / metabolism
  • Pancreatic Neoplasms / pathology
  • Pancreatic Neoplasms / therapy
  • Signal Transduction
  • Tumor Burden / genetics
  • Xenograft Model Antitumor Assays

Substances

  • Adaptor Proteins, Signal Transducing
  • Chemokines
  • DKK3 protein, human
  • Intercellular Signaling Peptides and Proteins
  • JNK Mitogen-Activated Protein Kinases