Antarlides F-H, new members of the antarlide family produced by Streptomyces sp. BB47

J Antibiot (Tokyo). 2017 May;70(5):595-600. doi: 10.1038/ja.2017.6. Epub 2017 Feb 8.

Abstract

Castration-resistant prostate cancer (CRPC) is the most aggressive form of this disease. CRPC remains dependent on androgen receptor (AR) signaling. Therefore, a novel AR antagonist, enzalutamide, is used clinically for the treatment of men with metastatic CRPC. However, enzalutamide-resistant AR has appeared, and a new type of AR antagonist is desired. Previously, in the course of screening for a new type of AR antagonist, we isolated a series of compounds, designated antarlides A-E, that share a novel 22-membered-ring macrocyclic structure and are produced by Streptomyces sp. BB47. In the present study, we found that this strain also produces antarlides F-H as minor components. Antarlide F is a novel geometric isomer of known antarlides. On the other hand, antarlides G and H are new members of the antarlide family that have a 20-membered-ring macrocyclic structure. Antarlides G and H inhibited the binding of androgen to AR in vitro at concentrations similar to those observed with antarlides A-E. In addition, antarlide G inhibited the transcriptional activity of not only wild-type AR but also enzalutamide-resistant AR, suggesting that antarlides with either 22- or 20-membered rings may serve as potent third-generation AR antagonists capable of overcoming resistance to enzalutamide.

MeSH terms

  • Androgen Receptor Antagonists / chemistry
  • Androgen Receptor Antagonists / isolation & purification
  • Androgen Receptor Antagonists / pharmacology*
  • Antineoplastic Agents / chemistry
  • Antineoplastic Agents / isolation & purification
  • Antineoplastic Agents / pharmacology*
  • Benzamides
  • Drug Resistance, Neoplasm
  • Humans
  • Macrocyclic Compounds / chemistry
  • Macrocyclic Compounds / isolation & purification
  • Macrocyclic Compounds / pharmacology*
  • Male
  • Nitriles
  • Phenylthiohydantoin / analogs & derivatives*
  • Phenylthiohydantoin / pharmacology
  • Prostatic Neoplasms, Castration-Resistant / drug therapy
  • Streptomyces / metabolism*

Substances

  • Androgen Receptor Antagonists
  • Antineoplastic Agents
  • Benzamides
  • Macrocyclic Compounds
  • Nitriles
  • Phenylthiohydantoin
  • enzalutamide