Prevention of prostate cancer by natural product MDM2 inhibitor GS25: in vitro and in vivo activities and molecular mechanisms

Carcinogenesis. 2018 Jul 30;39(8):1026-1036. doi: 10.1093/carcin/bgy063.

Abstract

Prostate cancer remains a major health problem in the USA and worldwide. There is an urgent need to develop novel approaches to preventing primary and metastatic prostate cancer. We have identified 25-OCH3-protopanaxadiol (GS25), the most active ginsenoside that has been identified so far; it has potent activity against human cancers, including prostate cancer. However, it has not been proven if GS25 could be a safe and effective agent for cancer prevention. In this study, we used the TRAMP model and clearly demonstrated that GS25 inhibited prostate tumorigenesis and metastasis with minimal host toxicity. Mechanistically, GS25 directly bound to the RING domain of MDM2, disrupted MDM2-MDMX binding and induced MDM2 protein degradation, resulting in strong inhibition of prostate cancer cell growth and metastasis, independent of p53 and androgen receptor status. In conclusion, our in vitro and in vivo data support the potential use of GS25 in prevention of primary and metastatic prostate cancer.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Cycle Proteins
  • Cell Line, Tumor
  • Disease Models, Animal
  • Drug Screening Assays, Antitumor
  • Humans
  • Male
  • Mice
  • Mice, Transgenic
  • Nuclear Proteins / metabolism
  • Prostatic Neoplasms / drug therapy*
  • Prostatic Neoplasms / genetics
  • Prostatic Neoplasms / pathology
  • Protein Binding / drug effects
  • Proteolysis / drug effects
  • Proto-Oncogene Proteins / metabolism
  • Proto-Oncogene Proteins c-mdm2 / antagonists & inhibitors*
  • Proto-Oncogene Proteins c-mdm2 / metabolism
  • RING Finger Domains / drug effects
  • Triterpenes / pharmacology*
  • Triterpenes / therapeutic use

Substances

  • 25-methoxydammarane-3,12,20-triol
  • Cell Cycle Proteins
  • MDM4 protein, human
  • Mdm4 protein, mouse
  • Nuclear Proteins
  • Proto-Oncogene Proteins
  • Triterpenes
  • MDM2 protein, human
  • Mdm2 protein, mouse
  • Proto-Oncogene Proteins c-mdm2