Enterolactone induces apoptosis in human prostate carcinoma LNCaP cells via a mitochondrial-mediated, caspase-dependent pathway

Mol Cancer Ther. 2007 Sep;6(9):2581-90. doi: 10.1158/1535-7163.MCT-07-0220.

Abstract

The mammalian lignan enterolactone is a major metabolite of plant-based lignans that has been shown to inhibit the growth and development of prostate cancer. However, little is known about the mechanistic basis for its anticancer activity. In this study, we report that enterolactone selectively suppresses the growth of LNCaP prostate cancer cells by triggering apoptosis. Mechanistic studies showed that enterolactone-induced apoptosis was characterized by a dose-dependent loss of mitochondrial membrane potential, release of cytochrome c and cleavage of procaspase-3 and poly(ADP-ribose)-polymerase (PARP). Caspase dependence was indicated by the ability of the pan-caspase inhibitor z-VAD-fmk to attenuate enterolactone-mediated apoptosis. Mechanistic studies suggested roles for Akt, GSK-3beta, MDM2, and p53 in enterolactone-dependent apoptosis. Our findings encourage further studies of enterolactone as a promising chemopreventive agent against prostate cancer.

Publication types

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

MeSH terms

  • 4-Butyrolactone / analogs & derivatives*
  • 4-Butyrolactone / pharmacology
  • Apoptosis / drug effects*
  • Caspases / metabolism*
  • Cell Survival / drug effects
  • Cytochromes c / metabolism
  • Enzyme Activation / drug effects
  • Glycogen Synthase Kinase 3 / metabolism
  • Glycogen Synthase Kinase 3 beta
  • Humans
  • Immunoblotting
  • In Situ Nick-End Labeling
  • Lignans / pharmacology*
  • Male
  • Membrane Potential, Mitochondrial / drug effects*
  • Mitochondria / drug effects*
  • Mitochondria / metabolism
  • Phytoestrogens / pharmacology*
  • Poly(ADP-ribose) Polymerases / metabolism
  • Prostatic Neoplasms / drug therapy*
  • Prostatic Neoplasms / metabolism
  • Prostatic Neoplasms / pathology
  • Proto-Oncogene Proteins c-akt / metabolism
  • Proto-Oncogene Proteins c-mdm2 / metabolism
  • Tumor Cells, Cultured / drug effects
  • Tumor Cells, Cultured / metabolism
  • Tumor Suppressor Protein p53 / metabolism

Substances

  • Lignans
  • Phytoestrogens
  • Tumor Suppressor Protein p53
  • Cytochromes c
  • MDM2 protein, human
  • Proto-Oncogene Proteins c-mdm2
  • Poly(ADP-ribose) Polymerases
  • GSK3B protein, human
  • Glycogen Synthase Kinase 3 beta
  • Proto-Oncogene Proteins c-akt
  • Glycogen Synthase Kinase 3
  • Caspases
  • 4-Butyrolactone
  • 2,3-bis(3'-hydroxybenzyl)butyrolactone