Exploitation of heparanase inhibitors from microbial metabolites using an efficient visual screening system

J Antibiot (Tokyo). 2004 Feb;57(2):136-42. doi: 10.7164/antibiotics.57.136.

Abstract

In this paper we describe the establishment of an efficient visual method for screening heparanase inhibitors, and we present the results of screening 10,000 microbial culture broths. Heparanase-overexpressing stable clones of the human hepatocellular carcinoma HepG2 cells were established and used as an enzyme source. Digestion of heparan sulfate (HS) was detected using novel HS-containing tablets or SDS-polyacrylamide gel electrophoresis. This method was able to find suramin, a known heparanase inhibitor, from a library of typical enzyme inhibitors. By screening 10,000 culture broths of microorganisms (actinomycetes, fungi, and bacteria) an actinomycete strain, RK99-A234, was found to have heparanase inhibitory activity. RK-682 was identified in the fermentation broth as a heparanase inhibitor, IC50 = 17 microM.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actinobacteria / metabolism
  • Animals
  • Blotting, Western
  • Carcinoma, Hepatocellular / drug therapy
  • Carcinoma, Hepatocellular / pathology
  • Cell Line, Tumor
  • Clone Cells
  • Culture Media
  • DNA, Complementary / biosynthesis
  • DNA, Complementary / genetics
  • Drug Evaluation, Preclinical
  • Electrophoresis, Polyacrylamide Gel
  • Enzyme Inhibitors / chemistry
  • Enzyme Inhibitors / isolation & purification
  • Enzyme Inhibitors / pharmacology*
  • Glucuronidase / antagonists & inhibitors*
  • Glucuronidase / biosynthesis
  • Heparitin Sulfate / metabolism
  • Humans
  • Liver Neoplasms / drug therapy
  • Liver Neoplasms / pathology
  • Phosphoprotein Phosphatases / antagonists & inhibitors*
  • Phosphoprotein Phosphatases / chemistry
  • Phosphoprotein Phosphatases / isolation & purification
  • Phosphoprotein Phosphatases / pharmacology*
  • Transfection

Substances

  • Culture Media
  • DNA, Complementary
  • Enzyme Inhibitors
  • RK 682
  • Heparitin Sulfate
  • Phosphoprotein Phosphatases
  • heparanase
  • Glucuronidase