Inhibitory action of pristimerin on hypoxia‑mediated metastasis involves stem cell characteristics and EMT in PC-3 prostate cancer cells

Oncol Rep. 2015 Mar;33(3):1388-94. doi: 10.3892/or.2015.3708. Epub 2015 Jan 7.

Abstract

The aim of the present study was to investigate whether pristimerin affects the bone metastasis, stem cell characteristics and epithelial-mesenchymal transition (EMT) of prostate cancer (PCa) PC-3 cells subjected to hypoxia. The PC-3 cells were cultured under hypoxia or normoxia for 48 h and were then treated with increasing concentrations of pristimerin from 0 to 0.8 µmol/l, under normoxia. Hypoxia‑inducible factor-1α (HIF-1α) was detected by western blotting. Proliferation was assessed with the CCK-8 assay. Transwell invasion assay was used to analyze the potency of invasion. Stem cell characteristics were detected by sphere formation, colony formation assay and western blotting, including CD44, KLF4, OCT4 and AGO2, which are stem cell characteristic-related markers. EMT was confirmed by the expression changes of EMT-related markers, including N-cadherin, fibronectin, vimentin and ZEB1, which were evaluated by western blotting. The addition of pristimerin to the medium reduced the hypoxia-induced PC-3 cell proliferation in a dose-dependent manner. Pristimerin effectively inhibited hypoxia‑induced invasion of the PCa cells in vitro. Moreover, the treatment of cells with pristimerin induced the reversal of hypoxia-induced stem cell characteristics and EMT, which was confirmed by sphere formation, colony formation assay and the expression changes of CSC- and EMT-related markers. The reversal of hypoxia‑induced stem cell characteristics and EMT in the PCa cells by low-dose pristimerin was dose‑dependent. These results showed that treatment with pristimerin may be a potential strategy for the suppression of hypoxia-induced metastasis through the reversal of hypoxia-induced stem cell characteristics and EMT in cancer cells, which justifies the potential use of pristimerin as a practical chemopreventive approach for patients with PCa.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antineoplastic Agents / pharmacology
  • Argonaute Proteins / metabolism
  • Bone Neoplasms / drug therapy
  • Bone Neoplasms / secondary*
  • Cadherins / biosynthesis
  • Cell Hypoxia / drug effects*
  • Cell Proliferation / drug effects
  • Cell Transformation, Neoplastic / drug effects
  • Epithelial-Mesenchymal Transition / drug effects*
  • Fibronectins / biosynthesis
  • Gene Expression Regulation, Neoplastic / drug effects
  • Homeodomain Proteins / biosynthesis
  • Humans
  • Hyaluronan Receptors / metabolism
  • Hypoxia-Inducible Factor 1, alpha Subunit / metabolism
  • Kruppel-Like Factor 4
  • Kruppel-Like Transcription Factors / metabolism
  • Male
  • Neoplasm Invasiveness / pathology
  • Neoplastic Stem Cells / drug effects
  • Octamer Transcription Factor-3 / metabolism
  • Pentacyclic Triterpenes
  • Prostatic Neoplasms / drug therapy*
  • Prostatic Neoplasms / pathology
  • Spheroids, Cellular / drug effects
  • Transcription Factors / biosynthesis
  • Triterpenes / pharmacology*
  • Tumor Cells, Cultured
  • Vimentin / biosynthesis
  • Zinc Finger E-box-Binding Homeobox 1

Substances

  • AGO2 protein, human
  • Antineoplastic Agents
  • Argonaute Proteins
  • CD44 protein, human
  • Cadherins
  • Fibronectins
  • HIF1A protein, human
  • Homeodomain Proteins
  • Hyaluronan Receptors
  • Hypoxia-Inducible Factor 1, alpha Subunit
  • KLF4 protein, human
  • Kruppel-Like Factor 4
  • Kruppel-Like Transcription Factors
  • Octamer Transcription Factor-3
  • POU5F1 protein, human
  • Pentacyclic Triterpenes
  • Transcription Factors
  • Triterpenes
  • Vimentin
  • ZEB1 protein, human
  • Zinc Finger E-box-Binding Homeobox 1
  • celastrol