In vitro profiling of epigenetic modifications underlying heavy metal toxicity of tungsten-alloy and its components

Ranjana Verma*, Xiufen Xu, Manoj K. Jaiswal, Cara Olsen, David Mears, Giuseppina Caretti, Zygmunt Galdzicki

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

32 Scopus citations


Tungsten-alloy has carcinogenic potential as demonstrated by cancer development in rats with intramuscular implanted tungsten-alloy pellets. This suggests a potential involvement of epigenetic events previously implicated as environmental triggers of cancer. Here, we tested metal induced cytotoxicity and epigenetic modifications including H3 acetylation, H3-Ser10 phosphorylation and H3-K4 trimethylation. We exposed human embryonic kidney (HEK293), human neuroepithelioma (SKNMC), and mouse myoblast (C2C12) cultures for 1-day and hippocampal primary neuronal cultures for 1-week to 50-200μg/ml of tungsten-alloy (91% tungsten/6% nickel/3% cobalt), tungsten, nickel, and cobalt. We also examined the potential role of intracellular calcium in metal mediated histone modifications by addition of calcium channel blockers/chelators to the metal solutions. Tungsten and its alloy showed cytotoxicity at concentrations > 50 μg/ml, while we found significant toxicity with cobalt and nickel for most tested concentrations. Diverse cell-specific toxic effects were observed, with C2C12 being relatively resistant to tungsten-alloy mediated toxic impact. Tungsten-alloy, but not tungsten, caused almost complete dephosphorylation of H3-Ser10 in C2C12 and hippocampal primary neuronal cultures with H3-hypoacetylation in C2C12. Dramatic H3-Ser10 dephosphorylation was found in all cobalt treated cultures with a decrease in H3 pan-acetylation in C2C12, SKNMC and HEK293. Trimethylation of H3-K4 was not affected. Both tungsten-alloy and cobalt mediated H3-Ser10 dephosphorylation were reversed with BAPTA-AM, highlighting the role of intracellular calcium, confirmed with 2-photon calcium imaging. In summary, our results for the first time reveal epigenetic modifications triggered by tungsten-alloy exposure in C2C12 and hippocampal primary neuronal cultures suggesting the underlying synergistic effects of tungsten, nickel and cobalt mediated by changes in intracellular calcium homeostasis and buffering.

Original languageEnglish
Pages (from-to)178-187
Number of pages10
JournalToxicology and Applied Pharmacology
Issue number3
StatePublished - 15 Jun 2011
Externally publishedYes


  • 2-photon calcium imaging
  • Calcium channel blockers
  • Calcium chelators
  • Cobalt
  • Cytotoxicity
  • Epigenetics
  • H3-histone modifications
  • Nickel
  • Tungsten-alloy


Dive into the research topics of 'In vitro profiling of epigenetic modifications underlying heavy metal toxicity of tungsten-alloy and its components'. Together they form a unique fingerprint.

Cite this