Ethyl 1,8-naphthyridone-3-carboxylates downregulate human papillomavirus-16 E6 and E7 oncogene expression

J Med Chem. 2014 Jul 10;57(13):5649-63. doi: 10.1021/jm500340h. Epub 2014 Jun 25.

Abstract

Strong epidemiological and molecular data associate cervical cancer (CC) with high-risk human papillomavirus (HPV) infections. The carcinogenic mechanism depends mainly on the expression of E6 and E7 oncoproteins encoded by the viral genome. Using a cell-based high-throughput assay, an in-house library of compounds was screened identifying the 1,8-naphthyridone 1 that efficiently inhibited the transcription driven by the long control region of the HPV genome. A series of analogues were then synthesized, obtaining more potent derivatives able to downregulate E6 and E7 transcripts in HPV-16-positive CC CaSki cells. An unusual structural insight emerged for the C-3 position of the 1,8-naphthyridone core, where the ethyl carboxylate esters, but not the carboxylic acids, are responsible for the activity. In vitro uptake studies showed that the 3-ethyl carboxylates do not act as prodrugs. The 1,8-naphthyridones emerged as valid starting points for the development of innovative agents potentially useful for the treatment of HPV-induced CC.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Line, Tumor
  • Down-Regulation
  • Female
  • Humans
  • Naphthyridines / pharmacology*
  • Oncogene Proteins, Viral / biosynthesis*
  • Papillomaviridae / drug effects
  • Papillomaviridae / metabolism*
  • Repressor Proteins / biosynthesis*
  • Uterine Cervical Neoplasms / genetics

Substances

  • E6 protein, Human papillomavirus type 16
  • Naphthyridines
  • Oncogene Proteins, Viral
  • Repressor Proteins