Gold(I)-triphenylphosphine complexes with hypoxanthine-derived ligands: in vitro evaluations of anticancer and anti-inflammatory activities

PLoS One. 2014 Sep 16;9(9):e107373. doi: 10.1371/journal.pone.0107373. eCollection 2014.

Abstract

A series of gold(I) complexes involving triphenylphosphine (PPh3) and one N-donor ligand derived from deprotonated mono- or disubstituted hypoxanthine (HLn) of the general composition [Au(Ln)(PPh3)] (1-9) is reported. The complexes were thoroughly characterized, including multinuclear high resolution NMR spectroscopy as well as single crystal X-ray analysis (for complexes 1 and 3). The complexes were screened for their in vitro cytotoxicity against human cancer cell lines MCF7 (breast carcinoma), HOS (osteosarcoma) and THP-1 (monocytic leukaemia), which identified the complexes 4-6 as the most promising representatives, who antiproliferative activity was further tested against A549 (lung adenocarcinoma), G-361 (melanoma), HeLa (cervical cancer), A2780 (ovarian carcinoma), A2780R (ovarian carcinoma resistant to cisplatin), 22Rv1 (prostate cancer) cell lines. Complexes 4-6 showed a significantly higher in vitro anticancer effect against the employed cancer cells, except for G-361, as compared with the commercially used anticancer drug cisplatin, with IC50 ≈ 1-30 µM. Anti-inflammatory activity was evaluated in vitro by the assessment of the ability of the complexes to modulate secretion of the pro-inflammatory cytokines, i.e. tumour necrosis factor-α (TNF-α) and interleukin-1β (IL-1β), in the lipopolysaccharide-activated macrophage-like THP-1 cell model. The results of this study identified the complexes as auspicious anti-inflammatory agents with similar or better activity as compared with the clinically applied gold-based antiarthritic drug Auranofin. In an effort to explore the possible mechanisms responsible for the biological effect, the products of interactions of selected complexes with sulfur-containing biomolecules (L-cysteine and reduced glutathione) were studied by means of the mass-spectrometry study.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Inflammatory Agents / chemistry
  • Anti-Inflammatory Agents / pharmacology*
  • Anti-Inflammatory Agents / toxicity
  • Antineoplastic Agents / chemistry
  • Antineoplastic Agents / pharmacology*
  • Antineoplastic Agents / toxicity
  • Cell Line
  • Cell Line, Tumor
  • Gold / chemistry*
  • Humans
  • Hypoxanthine / chemistry
  • Hypoxanthine / pharmacology*
  • Hypoxanthine / toxicity
  • Macrophages / drug effects
  • Macrophages / metabolism
  • Models, Molecular
  • Molecular Conformation
  • Molecular Structure
  • Nuclear Magnetic Resonance, Biomolecular
  • Organophosphorus Compounds / chemistry
  • Organophosphorus Compounds / pharmacology*
  • Organophosphorus Compounds / toxicity

Substances

  • Anti-Inflammatory Agents
  • Antineoplastic Agents
  • Organophosphorus Compounds
  • triphenylphosphine
  • Hypoxanthine
  • Gold

Grants and funding

The authors gratefully thank the Operational Program Research and Development for Innovations - European Regional Development Fund (CZ.1.05/2.1.00/03.0058), the National Program of Sustainability I (LO1305) of the Ministry of Education, Youth and Sports of the Czech Republic and Palacký University in Olomouc (IGA_PrF_2014009). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.