The antitumor agent PBT-1 directly targets HSP90 and hnRNP A2/B1 and inhibits lung adenocarcinoma growth and metastasis

J Med Chem. 2014 Feb 13;57(3):677-85. doi: 10.1021/jm401686b. Epub 2014 Jan 31.

Abstract

Natural products are the major sources of currently available anticancer drugs. We recently reported that phenanthrene-based tylophorine derivative-1 (PBT-1) may be a potential antitumor agent for lung adenocarcinoma. We therefore examined the direct targets of PBT-1 and their effects in inhibiting lung adenocarcinoma. We found that PBT-1 reduced the level of Slug and inhibits the migration, invasion, and filopodia formation of lung adenocarcinoma CL1-5 cells in vitro. In addition, PBT-1 displayed in vivo antitumor and antimetastasis activities against subcutaneous and orthotopic xenografts of CL1-5 cells in nude mice. Chemical proteomics showed that heat shock protein 90 (HSP90) and heterogeneous nuclear ribonucleoproteins A2/B1 (hnRNP A2/B1) bound PBT-1 in CL1-5 cells. Inhibition of HSP90 and hnRNP A2/B1 reduced the activation of AKT and Slug expression. Taken together, these findings suggest that PBT-1 binds to HSP90 and/or hnRNP A2/B1 and initiates antitumor activities by affecting Slug- and AKT-mediated metastasis and tumorigenesis.

Publication types

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

MeSH terms

  • 8,11,14-Eicosatrienoic Acid / analogs & derivatives*
  • 8,11,14-Eicosatrienoic Acid / pharmacology
  • 8,11,14-Eicosatrienoic Acid / therapeutic use
  • Adenocarcinoma / drug therapy
  • Adenocarcinoma / metabolism
  • Adenocarcinoma / pathology*
  • Adenocarcinoma of Lung
  • Animals
  • Antineoplastic Agents / pharmacology*
  • Antineoplastic Agents / therapeutic use
  • Cadherins / metabolism
  • Cell Line, Tumor
  • Cell Movement / drug effects
  • HSP90 Heat-Shock Proteins / antagonists & inhibitors*
  • HSP90 Heat-Shock Proteins / metabolism
  • Heterogeneous-Nuclear Ribonucleoprotein Group A-B / antagonists & inhibitors*
  • Heterogeneous-Nuclear Ribonucleoprotein Group A-B / metabolism
  • Humans
  • Lung Neoplasms / drug therapy
  • Lung Neoplasms / metabolism
  • Lung Neoplasms / pathology*
  • Male
  • Mice
  • Mice, Nude
  • Neoplasm Invasiveness / prevention & control
  • Neoplasm Metastasis
  • Neoplasm Transplantation
  • Proto-Oncogene Proteins c-akt / metabolism
  • Pseudopodia / drug effects
  • Pseudopodia / pathology

Substances

  • 8-hydroxy-11,12-cyclopropyleicosa-5,9,14-trienoic acid methyl ester
  • Antineoplastic Agents
  • Cadherins
  • HSP90 Heat-Shock Proteins
  • Heterogeneous-Nuclear Ribonucleoprotein Group A-B
  • Proto-Oncogene Proteins c-akt
  • 8,11,14-Eicosatrienoic Acid