Complexes of oxoplatin with rhein and ferulic acid ligands as platinum(iv) prodrugs with high anti-tumor activity

Dalton Trans. 2020 Feb 7;49(5):1613-1619. doi: 10.1039/c9dt04594e. Epub 2020 Jan 16.

Abstract

We herein designed two new PtIV prodrugs of oxoplatin (cis,cis,cis-[PtCl2(NH3)2(OH)2]), [PtIVCl2(NH3)2(O2C-FA)2] (Pt-2) and [PtIVCl2(NH3)2(O2C-RH)2] (Pt-3), by conjugating with ferulic acid (FA-COOH) and rhein (RH-COOH) which have well-known biological activities. Three other Pt(iv) complexes of [PtIVCl2(NH3)2(O2C-BA)2] (Pt-1), [PtIVCl2(NH3)2(O2C-CA)2] (Pt-4) and [PtIVCl2(NH3)2(O2C-TCA)2] (Pt-5) (where BA-COOH = benzoic acid, CA-COOH = crotonic acid and TCA-COOH = trans-cinnamic acid) were also prepared for the comparative study. Like most PtIV prodrug complexes, the cytotoxicity of Pt-3 containing the biologically active rhein (RH-COOH) ligand against lung carcinoma (A549 and A549/DDP) cells was higher than those of Pt-1, Pt-2, Pt-4, cisplatin and Pt-5. Moreover, the cytotoxicity of Pt-3 in HL-7702 normal cells was lower than those of PtIV derivatives bearing BA-COOH, FA-COOH, TCA-COOH and CA-COOH ligands. The highly efficacious Pt-2 and Pt-3 were found to accumulate strongly in the A549/DDP cells, with the prodrug Pt-3 showing highest levels of penetration into the mitochondria. The prodrug Pt-3 effectively entered the A549/DDP cells and caused mitochondrial damage, significantly greater than Pt-2. In addition, the prodrug Pt-3 exhibited higher antitumor efficacy (inhibition rates (IR) = 67.45%) than Pt-2 (28.12%) and cisplatin (33.05%) in the A549/DDP xenograft mouse model. Thus, the prodrug Pt-3 containing the rhein (RH-COOH) ligand is a promising candidate drug targeting the mitochondria.

MeSH terms

  • A549 Cells
  • Animals
  • Anthraquinones / chemistry
  • Anthraquinones / pharmacology*
  • Antineoplastic Agents / chemical synthesis
  • Antineoplastic Agents / chemistry
  • Antineoplastic Agents / pharmacology*
  • Apoptosis / drug effects
  • Cell Proliferation / drug effects
  • Cisplatin / analogs & derivatives*
  • Cisplatin / chemistry
  • Cisplatin / pharmacology
  • Coumaric Acids / chemistry
  • Coumaric Acids / pharmacology*
  • Dose-Response Relationship, Drug
  • Drug Screening Assays, Antitumor
  • Humans
  • Ligands
  • Mice
  • Mitochondria / drug effects
  • Mitochondria / metabolism
  • Molecular Structure
  • Neoplasms, Experimental / drug therapy
  • Neoplasms, Experimental / metabolism
  • Neoplasms, Experimental / pathology
  • Organoplatinum Compounds / chemical synthesis
  • Organoplatinum Compounds / chemistry
  • Organoplatinum Compounds / pharmacology*
  • Prodrugs / chemical synthesis
  • Prodrugs / chemistry
  • Prodrugs / pharmacology*
  • Structure-Activity Relationship

Substances

  • Anthraquinones
  • Antineoplastic Agents
  • Coumaric Acids
  • Ligands
  • Organoplatinum Compounds
  • Prodrugs
  • ferulic acid
  • Cisplatin
  • diamminedichlorodihydroxyplatinum IV
  • rhein