Design, synthesis and characterization of novel quinacrine analogs that preferentially kill cancer over non-cancer cells through the down-regulation of Bcl-2 and up-regulation of Bax and Bad

Eur J Med Chem. 2017 Sep 8:137:156-166. doi: 10.1016/j.ejmech.2017.05.052. Epub 2017 May 27.

Abstract

Both quinacrine, which contains a 9-aminoacridine scaffold, and thiazolidin-4-one are promising anticancer leads. In an attempt to develop effective and potentially safe anticancer agents, we synthesized 23 novel hybrid compounds by linking the main structural unit of the 9-aminoacridine ring with the thiazolidin-4-one ring system, followed by examination of their anticancer effects against three human breast tumor cell lines and matching non-cancer cells. Most of the hybrid compounds showed good activities, and many of them possessed the preferential killing property against cancer over non-cancer cells. In particular, 3-[3-(6-chloro-2-methoxy-acridin-9-ylamino)-propyl]-2-(2,6-difluoro-phenyl)-thiazolidin-4-one (11; VR118) effectively killed/inhibited proliferation of cancer cells at IC50 values in the range of 1.2-2.4 μM. Furthermore, unlike quinacrine or cisplatin, compound 11 showed strong selectivity for cancer cell killing, as it could kill cancer cells 7.6-fold (MDA-MB231 vs MCF10A) to 14.7-fold (MCF7 vs MCF10A) more effectively than matching non-cancer cells. Data from flow cytometry, TUNEL and Western blot assays showed that compound 11 kills cancer cells by apoptosis through the down-regulation of Bcl-2 (but not Bcl-XL) survival protein and up-regulation of Bad and Bax pro-apoptotic proteins. Thus, compound 11 is a highly promising lead for an effective and potentially anticancer therapy.

Keywords: 9-aminoacridine; Anticancer agents; Apoptosis; Hybrid approach; Quinacrine; Thiazolidin-4-one.

MeSH terms

  • Antineoplastic Agents / chemical synthesis
  • Antineoplastic Agents / chemistry
  • Antineoplastic Agents / pharmacology*
  • Cell Death / drug effects
  • Cell Line, Tumor
  • Cell Proliferation / drug effects
  • Dose-Response Relationship, Drug
  • Down-Regulation / drug effects
  • Drug Design*
  • Drug Screening Assays, Antitumor
  • Humans
  • Molecular Structure
  • Proto-Oncogene Proteins c-bcl-2 / antagonists & inhibitors*
  • Proto-Oncogene Proteins c-bcl-2 / metabolism
  • Quinacrine / chemical synthesis
  • Quinacrine / chemistry
  • Quinacrine / pharmacology*
  • Structure-Activity Relationship
  • Up-Regulation / drug effects
  • bcl-2-Associated X Protein / metabolism*
  • bcl-Associated Death Protein / metabolism*

Substances

  • Antineoplastic Agents
  • BAD protein, human
  • BAX protein, human
  • Proto-Oncogene Proteins c-bcl-2
  • bcl-2-Associated X Protein
  • bcl-Associated Death Protein
  • Quinacrine