OSU-03012, a novel celecoxib derivative, induces reactive oxygen species-related autophagy in hepatocellular carcinoma

Cancer Res. 2008 Nov 15;68(22):9348-57. doi: 10.1158/0008-5472.CAN-08-1642.

Abstract

Hepatocellular carcinoma (HCC) is the fifth most common cancer and the third leading cause of cancer death worldwide. Systemic treatments for HCC have been largely unsuccessful. OSU-03012 is a derivative of celecoxib with anticancer activity. The mechanism of action is presumably 3-phosphoinositide-dependent kinase 1 (PDK1) inhibition. This study investigated the potential of OSU-03012 as a treatment for HCC. OSU-03012 inhibited cell growth of Huh7, Hep3B, and HepG2 cells with IC(50) below 1 mumol/L. In Huh7 cells, OSU-03012 did not suppress PDK1 or AKT activity. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay and flow cytometry analysis indicated that OSU-03012 did not induce cellular apoptosis. Instead, morphologic studies by light and electron microscopy, as well as special biological staining with monodansylcadaverine, acridine orange, and microtubule-associated protein 1 light chain 3, revealed OSU-03012-induced autophagy of Huh7 cells. This OSU-03012-induced autophagy was inhibited by 3-methyladenine. Moreover, reactive oxygen species (ROS) accumulation was detected after OSU-03012 treatment. Blocking ROS accumulation with ROS scavengers inhibited autophagy formation, indicating that ROS accumulation and subsequent autophagy formation might be a major mechanism of action of OSU-03012. Daily oral treatment of BALB/c nude mice with OSU-03012 suppressed the growth of Huh7 tumor xenografts. Electron microscopic observation indicated that OSU-03012 induced autophagy in vivo. Together, our results show that OSU-03012 induces autophagic cell death but not apoptosis in HCC and that the autophagy-inducing activity is at least partially related to ROS accumulation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3-Phosphoinositide-Dependent Protein Kinases
  • Adenine / analogs & derivatives
  • Adenine / pharmacology
  • Animals
  • Apoptosis / drug effects
  • Autophagy / drug effects*
  • Autophagy-Related Protein 5
  • Carcinoma, Hepatocellular / drug therapy*
  • Carcinoma, Hepatocellular / pathology
  • Cell Line, Tumor
  • Humans
  • Liver Neoplasms / drug therapy*
  • Liver Neoplasms / pathology
  • Male
  • Mice
  • Mice, Inbred BALB C
  • Microtubule-Associated Proteins / antagonists & inhibitors
  • Protein Kinase Inhibitors / pharmacology*
  • Protein Serine-Threonine Kinases / antagonists & inhibitors*
  • Pyrazoles / pharmacology*
  • Reactive Oxygen Species / metabolism*
  • Sulfonamides / pharmacology*
  • Xenograft Model Antitumor Assays

Substances

  • ATG5 protein, human
  • Autophagy-Related Protein 5
  • Microtubule-Associated Proteins
  • OSU 03012
  • Protein Kinase Inhibitors
  • Pyrazoles
  • Reactive Oxygen Species
  • Sulfonamides
  • 3-methyladenine
  • 3-Phosphoinositide-Dependent Protein Kinases
  • PDPK1 protein, human
  • Pdpk1 protein, mouse
  • Protein Serine-Threonine Kinases
  • Adenine