The diaryl oxazole PC-046 is a tubulin-binding agent with experimental anti-tumor efficacy in hematologic cancers

Invest New Drugs. 2013 Dec;31(6):1616-25. doi: 10.1007/s10637-013-0019-8. Epub 2013 Sep 14.

Abstract

Microtubule targeting agents are among the most widely used chemotherapeutics for both solid and hematological malignancies. This study characterizes the diaryl-oxazole based anticancer agent PC-046, which was originally identified for development based on selective activity in deleted in pancreas cancer locus 4 (DPC4/SMAD4) deficient tumors. PC-046 has growth inhibitory activity in a variety of tumor types in vitro, and efficacy in SCID mice was shown in human tumor xenografts of MV-4-11 acute myeloid leukemia, MM.1S multiple myeloma, and DU-145 prostate cancer. Pharmacokinetic studies demonstrated relatively high oral bioavailability (71%) with distribution to both plasma and bone marrow. No myelosuppression was seen in non-tumor bearing SCID mice given a single dose just under the acute lethal dose. The COMPARE algorithm in the NCI-60 cell line panel demonstrated that PC-046 closely correlated to other known tubulin destabilizing agents (correlation coefficients ≈0.7 for vincristine and vinblastine). Mechanism of action studies showed cell cycle arrest in metaphase and inhibition of tubulin polymerization. Overall, these studies show that PC-046 is a synthetically-derived, small molecule microtubule destabilizing agent. Advantages over existing microtubule destabilizing agents include ease of synthesis, lack of MDR cross-resistance, good oral bioavailability and the lack of acute myelotoxicity.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Antineoplastic Agents / pharmacology
  • Antineoplastic Agents / therapeutic use*
  • Caspases / metabolism
  • Cell Cycle / drug effects
  • Cell Line, Tumor
  • Cell Survival / drug effects
  • Hematologic Neoplasms / drug therapy*
  • Hematologic Neoplasms / metabolism
  • Humans
  • Male
  • Mice
  • Mice, SCID
  • Oxazoles / pharmacology
  • Oxazoles / therapeutic use*
  • Prostatic Neoplasms / drug therapy
  • Prostatic Neoplasms / metabolism
  • Pyridines / pharmacology
  • Pyridines / therapeutic use*
  • Tubulin / metabolism
  • Tubulin Modulators / pharmacology
  • Tubulin Modulators / therapeutic use*
  • Xenograft Model Antitumor Assays

Substances

  • 5-(4-methoxyphenyl)-2-(3-(3-methoxyphenyl)pyridin-4-yl)oxazole
  • Antineoplastic Agents
  • Oxazoles
  • Pyridines
  • Tubulin
  • Tubulin Modulators
  • Caspases