Up-Regulation of Transient Receptor Potential Melastatin 6 Channel Expression by Tumor Necrosis Factor-α in the Presence of Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitor

J Cell Physiol. 2017 Oct;232(10):2841-2850. doi: 10.1002/jcp.25709. Epub 2017 Apr 25.


Anti-epidermal growth factor receptor (EGFR) drugs such as erlotinib and gefitinib cause a side effect of hypomagnesemia, but chemotherapy to treat this has not yet been developed. The transient receptor potential melastatin 6 (TRPM6) channel is involved in the reabsorption of Mg2+ in the renal tubule. We reported previously that the expression of TRPM6 is up-regulated by epidermal growth factor (EGF) in renal tubular epithelial NRK-52E and HEK293 cells. EGF-induced elevation of TRPM6 expression was inhibited by erlotinib, gefitinib, and lapatinib. We found that tumor necrosis factor-α (TNF-α) increases TRPM6 expression in the presence of erlotinib. Therefore, we investigated what molecules are involved in the up-regulation of TRPM6 expression by TNF-α. EGF increased the levels of phosphorylated extracellular signal-regulated kinase 1 and 2 (p-ERK1/2), which were inhibited by erlotinib. TNF-α did not change p-ERK1/2 levels, but increased the phosphorylation and nuclear localization of nuclear factor-κB (NF-κB), which were blocked by the NF-κB inhibitors BAY 11-7082 and pyrrolidinedithiocarbamate ammonium. Similarly, luciferase reporter activity of human TRPM6 was increased by TNF-α, which was blocked by NF-κB inhibitors, and was inhibited by a mutation in the κB-binding site in the proximal region of the TRPM6 promoter. A chromatin immunoprecipitation assay revealed that NF-κB binds to the κB-binding site, which was blocked by NF-κB inhibitors. In the presence of erlotinib, TNF-α increased Mg2+ influx, which was blocked by NF-κB inhibitors. These results suggest that TNF-α reverses the reduction in Mg2+ reabsorption caused by anti-EGFR drugs. J. Cell. Physiol. 232: 2841-2850, 2017. © 2016 Wiley Periodicals, Inc.

MeSH terms

  • Animals
  • Binding Sites
  • Epidermal Growth Factor / pharmacology
  • ErbB Receptors / antagonists & inhibitors*
  • ErbB Receptors / metabolism
  • Erlotinib Hydrochloride / toxicity*
  • Extracellular Signal-Regulated MAP Kinases / metabolism
  • Gefitinib
  • HEK293 Cells
  • Humans
  • Kidney Tubules / drug effects*
  • Kidney Tubules / metabolism
  • Kidney Tubules / physiopathology
  • Lapatinib
  • Magnesium / metabolism*
  • NF-kappa B / metabolism
  • Phosphorylation
  • Promoter Regions, Genetic
  • Protein Binding
  • Protein Kinase Inhibitors / toxicity*
  • Quinazolines / toxicity
  • Rats
  • Renal Reabsorption / drug effects*
  • TRPM Cation Channels / drug effects*
  • TRPM Cation Channels / metabolism
  • Time Factors
  • Transfection
  • Tumor Necrosis Factor-alpha / pharmacology*
  • Up-Regulation


  • NF-kappa B
  • Protein Kinase Inhibitors
  • Quinazolines
  • TRPM Cation Channels
  • TRPM6 protein, human
  • TRPM6 protein, rat
  • Tumor Necrosis Factor-alpha
  • Lapatinib
  • Epidermal Growth Factor
  • Erlotinib Hydrochloride
  • EGFR protein, human
  • Egfr protein, rat
  • ErbB Receptors
  • Extracellular Signal-Regulated MAP Kinases
  • Magnesium
  • Gefitinib