IL-6, a risk factor for hepatocellular carcinoma: FLLL32 inhibits IL-6-induced STAT3 phosphorylation in human hepatocellular cancer cells

Cell Cycle. 2010 Sep 1;9(17):3423-7. doi: 10.4161/cc.9.17.12946. Epub 2010 Sep 8.

Abstract

Hepatocellular carcinoma (HCC) is one of the most common human cancers and the patients' five-year survival rate is very low. Growing evidence indicates that interleukin-6 (IL-6) is a risk factor for HCC. High serum IL-6 may promote HCC development in hepatitis B patients. Therefore, IL-6 could be considered a HCC biomarker and blockade of IL-6 pathway may be a promising therapeutic alternative for HCC. STAT3 is major pathway to mediate signal from IL-6 to the nucleus, where different genes associated with proliferation and apoptosis are regulated. We previous reported that IL-6 induces cell survival upon drug treatment in HCC cells and inhibition of IL-6/STAT3 pathway using anti-IL-6 antibody or STAT3 small-molecule inhibitor LLL12 reduces this effect. Here we summarized the recent studies of IL-6 in HCC and showed another STAT3 small-molecule inhibitor FLLL32 also blocked IL-6-induced STAT3 activation in HCC cells. FLLL32 is a novel curcumin analogue, which has been described to suppress the constitutive activation of STAT3 in pancreatic and breast cancer cells in vitro and vivo. We demonstrated that FLLL32 blocked IL-6-induced STAT3 phosphorylation and nuclear translocation.

MeSH terms

  • Carcinoma, Hepatocellular / metabolism*
  • Cell Line, Tumor
  • Cell Nucleus / metabolism
  • Curcumin / analogs & derivatives*
  • Curcumin / pharmacology
  • Humans
  • Interleukin-6 / antagonists & inhibitors*
  • Interleukin-6 / blood
  • Interleukin-6 / metabolism
  • Liver Neoplasms / metabolism*
  • Phosphorylation
  • Risk Factors
  • STAT3 Transcription Factor / antagonists & inhibitors*
  • STAT3 Transcription Factor / metabolism

Substances

  • FLLL 32
  • Interleukin-6
  • STAT3 Transcription Factor
  • Curcumin