Time Course of Changes in Sorafenib-Treated Hepatocellular Carcinoma Cells Suggests Involvement of Phospho-Regulated Signaling in Ferroptosis Induction

Proteomics. 2020 May;20(10):e2000006. doi: 10.1002/pmic.202000006. Epub 2020 May 18.


Ferroptosis is a form of regulated, non-apoptotic cell death characterized by excessive lipid peroxidation that can be triggered by inhibition of the cystine-glutamate antiporter, system Xc- . Sorafenib, an FDA-approved multi-kinase inhibitor drug that is used for treatment of hepatocellular carcinoma (HCC), has been shown to induce ferroptosis. Protein phosphorylation changes upon sorafenib treatment have been previously reported in patient studies and in cell culture. However, early phosphorylation changes during induction of ferroptosis are not reported. This work highlights these changes through a time course from 7 to 60 min of sorafenib treatment in human (SKHep1) HCC cells. A total of 6170 unique phosphosites from 2381 phosphoproteins are quantified, and phosphorylation changes occur after as little as 30 min of sorafenib treatment. By 60 min, notable changes included phosphosites significantly changing on p53 (P04637), CAD protein (P27708), and proteins important for iron homeostasis, such as heavy chain ferritin (FTH1; P02794), heme oxygenase 1 (HMOX1; P09601), and PCBP1 (Q15365). Additional sites on proteins in key regulatory pathways are identified, including sites in ferroptosis-related proteins, indicating the likely involvement of phospho-regulated signaling during ferroptosis induction.

Keywords: ferroptosis; hepatocellular carcimnoma; mass spectrometry; phosphoproteomics; proteomics.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Carcinoma, Hepatocellular / drug therapy*
  • Carcinoma, Hepatocellular / genetics
  • Carcinoma, Hepatocellular / pathology
  • Cell Line, Tumor
  • DNA-Binding Proteins / genetics
  • Ferritins / genetics
  • Ferroptosis / drug effects
  • Gene Expression Regulation, Neoplastic / drug effects
  • Heme Oxygenase-1 / genetics
  • Homeostasis / drug effects
  • Humans
  • Iron / metabolism
  • Lipid Peroxidation / drug effects
  • Liver Neoplasms / drug therapy*
  • Liver Neoplasms / genetics
  • Liver Neoplasms / pathology
  • Oxidoreductases / genetics
  • Phosphoproteins / genetics
  • Phosphorylation / drug effects*
  • Protein Kinase Inhibitors / pharmacology
  • RNA-Binding Proteins / genetics
  • Signal Transduction / drug effects
  • Sorafenib / pharmacology*


  • DNA-Binding Proteins
  • PCBP1 protein, human
  • Phosphoproteins
  • Protein Kinase Inhibitors
  • RNA-Binding Proteins
  • Ferritins
  • Sorafenib
  • Iron
  • FTH1 protein, human
  • Oxidoreductases
  • HMOX1 protein, human
  • Heme Oxygenase-1