A novel PI3K inhibitor displays potent preclinical activity against an androgen-independent and PTEN-deficient prostate cancer model established from the cell line PC3

Toxicol Lett. 2014 Aug 4;228(3):133-9. doi: 10.1016/j.toxlet.2014.05.003. Epub 2014 May 14.

Abstract

Recent studies demonstrated that targeting the phosphatidylinositide 3-kinase (PI3K)/AKT signaling pathway is a major strategy for the treatment of androgen-independent prostate cancer. In the present study, we developed an analog BENC-511 from a recently reported PI3K inhibitor S14161 by structural optimization. Using PC3 and DU145 as the model cell lines, we found PTEN-deficient PC3 cells were more sensitive than PTEN-expressing DU145 ones in terms of cell proliferation, apoptosis, and caspase-3 activation. These findings were consistent with the inhibition on PI3K/AKT signals. BENC-511 preferably suppressed AKT activation in PC3 over DU145 cells. Notably, PTEN restoration attenuated BENC-511 induced apoptosis. Moreover, BENC-511 displayed great therapeutic efficacy in a PC3-derived prostate cancer model in nude mice. With an oral dosage of 50mg/kg, BENC-511 decreased tumor growth more than 50% in 27 days, which was accompanied with PARP cleavage, but did not show overt toxicity. This study lays a solid rationale for the development of BENC-511 as a drug for the treatment of PTEN-deficient and androgen-independent prostate cancers.

Keywords: Androgen-independence; BENC-511; PI3K/AKT; PTEN; Prostate cancer.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Oral
  • Animals
  • Antineoplastic Agents / administration & dosage
  • Antineoplastic Agents / pharmacology*
  • Apoptosis / drug effects
  • Benzopyrans / administration & dosage
  • Benzopyrans / pharmacology*
  • Caspase 3 / metabolism
  • Cell Line, Tumor
  • Cell Proliferation / drug effects
  • Dose-Response Relationship, Drug
  • Enzyme Activation
  • Humans
  • Male
  • Mice
  • Mice, Nude
  • PTEN Phosphohydrolase / deficiency*
  • PTEN Phosphohydrolase / genetics
  • Phosphatidylinositol 3-Kinase / metabolism
  • Phosphoinositide-3 Kinase Inhibitors*
  • Poly(ADP-ribose) Polymerases / metabolism
  • Prostatic Neoplasms / drug therapy*
  • Prostatic Neoplasms / enzymology
  • Prostatic Neoplasms / genetics
  • Prostatic Neoplasms / pathology
  • Protein Kinase Inhibitors / administration & dosage
  • Protein Kinase Inhibitors / pharmacology*
  • Signal Transduction / drug effects
  • Time Factors
  • Transfection
  • Tumor Burden
  • Xenograft Model Antitumor Assays

Substances

  • 6-bromo-8-ethoxy-3-nitro-2H-chromene
  • Antineoplastic Agents
  • Benzopyrans
  • Phosphoinositide-3 Kinase Inhibitors
  • Protein Kinase Inhibitors
  • Poly(ADP-ribose) Polymerases
  • Phosphatidylinositol 3-Kinase
  • PTEN Phosphohydrolase
  • PTEN protein, human
  • CASP3 protein, human
  • Caspase 3