A combination of AZD5363 and FH5363 induces lethal autophagy in transformed hepatocytes

Cell Death Dis. 2020 Jul 17;11(7):540. doi: 10.1038/s41419-020-02741-1.

Abstract

Hepatocellular carcinoma (HCC) is one of the major causes of cancer-related death worldwide. High Akt activation and aberrant β-catenin expression contribute to HCC cell proliferation, stem cell generation, and metastasis. Several signaling pathway-specific inhibitors are in clinical trials and display different efficacies against HCC. In this study, we observed that a β-catenin inhibitor (FH535) displays antiproliferative effect on transformed human hepatocytes (THH). A combination treatment of these cells with FH535 and Akt inhibitor (AZD5363) exerted a stronger effect on cell death. Treatment of THH with AZD5363 and FH535 inhibited cell-cycle progression, enhanced autophagy marker protein expression, and autophagy-associated death, while FH535 treatment alone induced apoptosis. The use of chloroquine or z-VAD further verified these observations. Autophagy flux was evident from lowering marker proteins LAMP2, LAPTM4B, and autophagic protein expression by confocal microscopy using mCherry-EGFP-LC3 reporter construct. A combination treatment with AZD5363 and FH535 enhanced p53 expression, by modulating MDM2 activation; however, AZD5363 treatment alone restricted p53 to the nucleus by inhibiting dynamin-related protein activation. Nuclear p53 plays a crucial role for activation of autophagy by regulating the AMPK-mTOR-ULK1 pathway. Hep3B cells with null p53 did not modulate autophagy-dependent death from combination treatment. Together, our results strongly suggested that a combination treatment of Akt and β-catenin inhibitors exhibits efficient therapeutic potential for HCC.

Publication types

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

MeSH terms

  • Adenylate Kinase / metabolism
  • Autophagy / drug effects*
  • Biomarkers / metabolism
  • Cell Line, Transformed
  • Cell Nucleus / drug effects
  • Cell Nucleus / metabolism
  • Cell Proliferation / drug effects
  • Dynamins / metabolism
  • Hepatocytes / cytology*
  • Hepatocytes / drug effects
  • Hepatocytes / metabolism
  • Humans
  • Nuclear Proteins / metabolism
  • Protein Transport / drug effects
  • Proto-Oncogene Proteins c-mdm2 / metabolism
  • Pyrimidines / pharmacology*
  • Pyrroles / pharmacology*
  • Signal Transduction / drug effects
  • Subcellular Fractions / metabolism
  • Sulfonamides / pharmacology
  • TOR Serine-Threonine Kinases / metabolism
  • Tumor Suppressor Protein p53 / metabolism

Substances

  • Biomarkers
  • FH535
  • Nuclear Proteins
  • Pyrimidines
  • Pyrroles
  • SESN2 protein, human
  • Sulfonamides
  • Tumor Suppressor Protein p53
  • Proto-Oncogene Proteins c-mdm2
  • TOR Serine-Threonine Kinases
  • Adenylate Kinase
  • Dynamins
  • capivasertib