Combination of DESI2 and endostatin gene therapy significantly improves antitumor efficacy by accumulating DNA lesions, inducing apoptosis and inhibiting angiogenesis

Exp Cell Res. 2018 Oct 1;371(1):50-62. doi: 10.1016/j.yexcr.2018.07.040. Epub 2018 Jul 26.

Abstract

DESI2 is a novel pro-apoptotic gene. We previously reported that DESI2 overexpression induces S phase arrest and apoptosis by activating checkpoint kinases. This work was to test whether the combination of endostatin, an endogenous antiangiogenic inhibitor, with DESI2 could improve the therapy efficacy in vitro and in vivo. The recombinant plasmid co-expressing DESI2 and endostatin was encapsulated with DOTAP/Cholesterol cationic liposome. Mice bearing CT26 colon carcinoma and LL2 lung cancer were treated with the DNA-liposome complex. We found that, in vitro, the combination of DESI2 and endostatin more efficiently inhibited proliferation of CT26, LL2, HCT116 and A549 cancer cells via apoptosis, as assessed by MTT assay, colony-formation assays, flow cytometric analysis, hoechst staining and activation of caspase-3, respectively. In addition, DESI2 overexpression caused up-regulation of RPS7, a substrate of DESI2 deubiquitination. Furthermore, siRNA targeting RPS7 partially abrogated, whereas RPS7 overexpression enhanced DESI2-induced inhibition of cell proliferation. Importantly, the combination also caused DNA lesions accumulation, which further promotes apoptosis. Mechanistic rationale suggested that endostatin first inhibits DNA-PKcs kinase, and partly abrogated DESI2-induced phosphorylation of DNA-PKcs, leading to increase of DNA damage, then contributes to DESI2-induced apoptosis. In vivo, the combined gene therapy more significantly inhibited tumor growth and efficiently prolonged the survival of tumor bearing mice than mono therapy. The improved antitumor effect was associated with inhibition of cell proliferation via apoptosis, as analyzed by TUNEL assay and PCNA immunostaining. The combination also inhibited angiogenesis, as assessed by alginate-encapsulated tumor cell assay and CD31 staining. Our data suggest that the combined gene therapy of DESI2 and endostatin can significantly enhance the antitumor activity as a DNA lesions accumulator, apoptosis inducer and angiogenesis inhibitor. The present study may provide a novel method for the treatment of cancer.

Keywords: Anti-angiogenesis; Apoptosis; DESI2; DNA damage accumulation; Endostatin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • A549 Cells
  • Angiogenesis Inhibitors / chemistry
  • Angiogenesis Inhibitors / metabolism
  • Animals
  • Apoptosis / genetics
  • Carbon-Nitrogen Lyases / genetics*
  • Carbon-Nitrogen Lyases / metabolism
  • Caspase 3 / genetics
  • Caspase 3 / metabolism
  • Cell Proliferation
  • Cholesterol / chemistry
  • Cholesterol / metabolism
  • Colonic Neoplasms / genetics*
  • Colonic Neoplasms / mortality
  • Colonic Neoplasms / pathology
  • Colonic Neoplasms / therapy
  • DNA Fragmentation
  • Endostatins / genetics*
  • Endostatins / metabolism
  • Fatty Acids, Monounsaturated / chemistry
  • Fatty Acids, Monounsaturated / metabolism
  • Female
  • Gene Expression Regulation, Neoplastic*
  • Genetic Therapy / methods*
  • HCT116 Cells
  • Humans
  • Liposomes / administration & dosage
  • Liposomes / chemistry
  • Liposomes / metabolism
  • Lung Neoplasms / genetics*
  • Lung Neoplasms / mortality
  • Lung Neoplasms / pathology
  • Lung Neoplasms / therapy
  • Mice
  • Mice, Inbred C57BL
  • Plasmids / administration & dosage
  • Plasmids / chemistry
  • Plasmids / metabolism*
  • Quaternary Ammonium Compounds / chemistry
  • Quaternary Ammonium Compounds / metabolism
  • RNA, Small Interfering / genetics
  • RNA, Small Interfering / metabolism
  • Ribosomal Proteins / antagonists & inhibitors
  • Ribosomal Proteins / genetics
  • Ribosomal Proteins / metabolism
  • Signal Transduction
  • Survival Analysis
  • Xenograft Model Antitumor Assays

Substances

  • Angiogenesis Inhibitors
  • Endostatins
  • Fatty Acids, Monounsaturated
  • Liposomes
  • Quaternary Ammonium Compounds
  • RNA, Small Interfering
  • Ribosomal Proteins
  • ribosomal protein S7
  • Cholesterol
  • CASP3 protein, human
  • Caspase 3
  • Carbon-Nitrogen Lyases
  • DESI2 protein, human
  • 1,2-dioleoyloxy-3-(trimethylammonium)propane