Induction of apoptosis in Ehrlich ascites tumour cells via p53 activation by a novel small-molecule MDM2 inhibitor - LQFM030

J Pharm Pharmacol. 2016 Sep;68(9):1143-59. doi: 10.1111/jphp.12573. Epub 2016 Jun 28.

Abstract

Objective: The activation of the p53 pathway through the inhibition of MDM2 has been proposed as a novel therapeutic strategy against tumours. A series of cis-imidazoline analogues, termed nutlins, were reported to displace the recombinant p53 protein from its complex with MDM2 by binding to MDM2 in the p53 pocket, and exhibited an antitumour activity both in vitro and in vivo. Thus, the purpose of this study was to evaluate the antitumour properties of LQFM030 (2), a nutlin analogue created by employing the strategy of molecular simplification.

Methods: LQFM030 (2) cytotoxicity was evaluated in Ehrlich ascites tumour (EAT) cells, p53 wild type, by the trypan blue exclusion test, and the mechanisms involved in EAT cell death were investigated by light and fluorescence microscopy, flow cytometry, real-time PCR and Western blotting.

Key findings: Our results demonstrate that LQFM030 has dose-dependent antiproliferative activity and cytotoxic activity on EAT cells, induces the accumulation of p53 protein and promotes cell cycle arrest and apoptosis. p53 gene transcription was unaffected by LQFM030 (2); however, MDM2 mRNA increased and MDM2 protein decreased.

Conclusions: These results suggest that the small-molecule p53 activator LQFM030 (2) has the potential for further development as a novel cancer therapeutic agent.

Keywords: Ehrlich ascites tumor; LQFM030; MDM2; Nutlins; p53.

MeSH terms

  • Animals
  • Antineoplastic Agents / chemical synthesis
  • Antineoplastic Agents / pharmacology*
  • Antineoplastic Agents / therapeutic use
  • Apoptosis*
  • Carcinoma, Ehrlich Tumor / drug therapy
  • Carcinoma, Ehrlich Tumor / metabolism*
  • Cell Cycle Checkpoints
  • Cell Proliferation
  • Imidazoles / pharmacology
  • Mice
  • Piperidines / chemical synthesis
  • Piperidines / pharmacology
  • Piperidines / therapeutic use*
  • Proto-Oncogene Proteins c-mdm2 / antagonists & inhibitors*
  • Pyrazoles / chemical synthesis
  • Pyrazoles / pharmacology
  • Pyrazoles / therapeutic use*
  • RNA, Messenger / metabolism
  • Tumor Suppressor Protein p53 / metabolism*

Substances

  • Antineoplastic Agents
  • Imidazoles
  • LQFM030
  • Piperidines
  • Pyrazoles
  • RNA, Messenger
  • Tumor Suppressor Protein p53
  • Mdm2 protein, mouse
  • Proto-Oncogene Proteins c-mdm2