Indole-3-carbinol inhibits tumorigenicity of hepatocellular carcinoma cells via suppression of microRNA-21 and upregulation of phosphatase and tensin homolog

Biochim Biophys Acta. 2015 Jan;1853(1):244-53. doi: 10.1016/j.bbamcr.2014.10.017. Epub 2014 Oct 25.

Abstract

A major obstacle to successful treatment of hepatocellular carcinoma (HCC) is its high resistance to cytotoxic chemotherapy due to overexpression of multidrug resistance genes. Activation of the AKT pathway is known to be involved in chemoresistance in HCC; however, the underlying mechanisms modulating the AKT pathway by chemopreventive agents remain unclear. In the present study, we found that indole-3-carbinol (I3C) treatment for tumor cells repressed the AKT pathway by increasing the expression of phosphatase and tensin homolog (PTEN) in HCC xenograft tumor and HCC cell lines. qRT-PCR data showed that the expression of miR-21 and miR-221&222 was significantly reduced by I3C in HCC cells in vitro and in vivo. Reactivation of the AKT pathway via restoration of miR-21 was reversed by I3C. Ectopic expression of miR-21 mediated-accelerated wound healing was abrogated by I3C. Moreover, reducing the expression of miR-21 by anti-miR decreased the resistance of HCC cells to I3C. These results provide experimental evidences that I3C could function as a miR-21 regulator, leading to repression of the PTEN/AKT pathway and opening a new avenue for eradication of drug-resistant cells, thus potentially helping to improve the therapeutic outcome in patients diagnosed with HCC.

Keywords: Hepatocellular carcinoma; Indole-3-carbinol; PTEN; miR-21; miR-221&222.

Publication types

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

MeSH terms

  • Animals
  • Anticarcinogenic Agents / pharmacology*
  • Carcinoma, Hepatocellular / pathology
  • Carcinoma, Hepatocellular / prevention & control*
  • Cell Line, Tumor
  • Cell Proliferation / drug effects
  • Drug Resistance, Neoplasm
  • Female
  • Humans
  • Indoles / pharmacology*
  • Liver Neoplasms / pathology
  • Liver Neoplasms / prevention & control*
  • Mice
  • MicroRNAs / antagonists & inhibitors*
  • MicroRNAs / physiology
  • Microfilament Proteins / physiology*
  • PTEN Phosphohydrolase / physiology
  • Phosphoric Monoester Hydrolases / physiology*
  • Proto-Oncogene Proteins c-akt / physiology
  • Signal Transduction / physiology
  • Tensins

Substances

  • Anticarcinogenic Agents
  • Indoles
  • MIRN21 microRNA, human
  • MicroRNAs
  • Microfilament Proteins
  • Tensins
  • indole-3-carbinol
  • Proto-Oncogene Proteins c-akt
  • Phosphoric Monoester Hydrolases
  • PTEN Phosphohydrolase
  • PTEN protein, human