APOBEC3B and IL-6 form a positive feedback loop in hepatocellular carcinoma cells

Sci China Life Sci. 2017 Jun;60(6):617-626. doi: 10.1007/s11427-016-9058-6. Epub 2017 May 29.

Abstract

APOBEC3 protein families, a DNA cytidine deaminase, were up-regulated in multiple tumors. However, the relationship between Hepatocellular carcinoma (HCC) and APOBEC3B (A3B) remains unknown. It has been confirmed that interleukin-6 (IL-6) has significant impacts on oncogenesis of HCC. Here, we reported that the expression of IL-6 was substantially up-regulated by A3B in HepG2 cells. A3B induced IL-6 expression through relocating HuR to enhance the IL-6 mRNA stability. Further analysis indicated that IL-6 also increased the expression of A3B through JAK1/STAT3 signaling pathway, which formed a positive feedback to maintain the continuous expression of A3B and IL-6, and thereby promoted the prolonged non-resolving inflammation. Collectively, these findings suggest that A3B is essential for oncogenesis of HCC, and is a potential target for preventive intervention.

Keywords: APOBEC3B; HuR; hepatitis; hepatocellular carcinoma; interleukin-6.

MeSH terms

  • Animals
  • Carcinoma, Hepatocellular / metabolism
  • Carcinoma, Hepatocellular / pathology*
  • Cytidine Deaminase / metabolism*
  • Feedback
  • Hep G2 Cells
  • Humans
  • Interleukin-6 / metabolism*
  • Liver Neoplasms / metabolism
  • Liver Neoplasms / pathology*
  • Mice, Inbred C57BL
  • Minor Histocompatibility Antigens / metabolism*

Substances

  • Interleukin-6
  • Minor Histocompatibility Antigens
  • APOBEC3B protein, human
  • Cytidine Deaminase