The epigenetically regulated miR-494 associates with stem-cell phenotype and induces sorafenib resistance in hepatocellular carcinoma

Cell Death Dis. 2018 Jan 5;9(1):4. doi: 10.1038/s41419-017-0076-6.

Abstract

Hepatocellular carcinoma (HCC) represents the second cause of cancer-related mortality worldwide and is associated with poor prognosis, especially in patients not amenable for curative treatments. The multi-kinase inhibitor sorafenib represents the first-line treatment option for advanced HCC; nevertheless, its effectiveness is limited due to tumor heterogeneity as well as innate or acquired drug resistance, raising the need for new therapeutic strategies. MicroRNAs (miRNAs) involvement in treatment response as well as their safety and efficacy in preclinical models and clinical trials have been widely documented in the oncologic field, including HCC. Here, we identified miR-494 upregulation in a subgroup of human and rat HCCs with stem cell-like characteristics, as well as multiple epigenetic mechanisms involved in its aberrant expression in HCC cell lines and patients. Moreover, we identified p27, puma and pten among miR-494 targets, contributing to speed up cell cycle progression, enhance survival potential in stressful conditions and increase invasive and clonogenic capabilities. MiR-494 overexpression increased sorafenib resistance via mTOR pathway activation in HCC cell lines and, in line, high miR-494 levels associated with decreased sorafenib response in two HCC animal models. A sorafenib-combined anti-miR-494-based strategy revealed an enhanced anti-tumor potential with respect to sorafenib-only treatment in our HCC rat model. In conclusion, our findings suggested miR-494 as a possible therapeutic target as well as a candidate biomarker for patient stratification in advanced HCC.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • AC133 Antigen / genetics
  • AC133 Antigen / metabolism
  • Animals
  • Antineoplastic Agents / pharmacology
  • Antineoplastic Agents / therapeutic use
  • Carcinoma, Hepatocellular / drug therapy
  • Carcinoma, Hepatocellular / genetics
  • Carcinoma, Hepatocellular / pathology*
  • Cell Cycle Checkpoints / drug effects
  • Cell Line, Tumor
  • Cell Movement / drug effects
  • DNA (Cytosine-5-)-Methyltransferases / chemistry
  • DNA (Cytosine-5-)-Methyltransferases / genetics
  • DNA (Cytosine-5-)-Methyltransferases / metabolism
  • DNA Methyltransferase 3B
  • Disease Models, Animal
  • Drug Resistance, Neoplasm / genetics*
  • Epigenesis, Genetic*
  • Humans
  • Liver Neoplasms / drug therapy
  • Liver Neoplasms / genetics
  • Liver Neoplasms / pathology*
  • Mice
  • MicroRNAs / metabolism*
  • PTEN Phosphohydrolase / genetics
  • PTEN Phosphohydrolase / metabolism
  • Phenotype
  • Rats
  • Sorafenib / pharmacology
  • Sorafenib / therapeutic use
  • TOR Serine-Threonine Kinases / genetics
  • TOR Serine-Threonine Kinases / metabolism

Substances

  • AC133 Antigen
  • Antineoplastic Agents
  • MIRN494 microRNA, human
  • MicroRNAs
  • PROM1 protein, human
  • Sorafenib
  • DNA (Cytosine-5-)-Methyltransferases
  • MTOR protein, human
  • TOR Serine-Threonine Kinases
  • PTEN Phosphohydrolase
  • PTEN protein, human