Antiproliferative activity of (R)-4'-methylklavuzon on hepatocellular carcinoma cells and EpCAM+/CD133+ cancer stem cells via SIRT1 and Exportin-1 (CRM1) inhibition

Eur J Med Chem. 2019 Oct 15:180:224-237. doi: 10.1016/j.ejmech.2019.07.024. Epub 2019 Jul 9.

Abstract

Cytotoxic effects of (R)-4'-methylklavuzon were investigated on hepatocellular carcinoma cells (HuH-7 and HepG2) and HuH-7 EpCAM+/CD133+ cancer stem cells. IC50 of (R)-4'-methylklavuzon was found as 1.25 μM for HuH-7 parental cells while it was found as 2.50 μM for HuH-7 EpCAM+/CD133+ cancer stem cells. (R)-4'-methylklavuzon tended to show more efficient in vitro cytotoxicity with its lower IC50 values on hepatocellular carcinoma cell lines compared to its lead molecule, goniothalamin and FDA-approved drugs, sorafenib and regorafenib. Cell-based Sirtuin/HDAC enzyme activity measurements revealed that endogenous Sirtuin/HDAC enzymes were reduced by 40% compared to control. SIRT1 protein levels were upregulated indicating triggered DNA repair mechanism. p53 was overexpressed in HepG2 cells. (R)-4'-methylklavuzon inhibited CRM1 protein providing increased retention of p53 and RIOK2 protein in the nucleus. HuH-7 parental and EpCAM+/CD133+ cancer stem cell spheroids lost intact morphology. 3D HepG2 spheroid viabilities were decreased in a correlation with upregulation in p53 protein levels.

Keywords: CRM1 inhibitor; Cancer stem cell; Hepatocellular carcinoma; Klavuzon; SIRT1 inhibitor; Topoisomerase I inhibitor.

MeSH terms

  • AC133 Antigen / antagonists & inhibitors*
  • AC133 Antigen / metabolism
  • Antineoplastic Agents / chemical synthesis
  • Antineoplastic Agents / chemistry
  • Antineoplastic Agents / pharmacology*
  • Carcinoma, Hepatocellular / drug therapy*
  • Carcinoma, Hepatocellular / metabolism
  • Carcinoma, Hepatocellular / pathology
  • Cell Proliferation / drug effects
  • Cell Survival / drug effects
  • Dose-Response Relationship, Drug
  • Drug Screening Assays, Antitumor
  • Epithelial Cell Adhesion Molecule / antagonists & inhibitors*
  • Epithelial Cell Adhesion Molecule / metabolism
  • Exportin 1 Protein
  • Hep G2 Cells
  • Humans
  • Karyopherins / antagonists & inhibitors*
  • Karyopherins / metabolism
  • Liver Neoplasms / drug therapy*
  • Liver Neoplasms / metabolism
  • Liver Neoplasms / pathology
  • Molecular Structure
  • Naphthalenes / chemical synthesis
  • Naphthalenes / chemistry
  • Naphthalenes / pharmacology*
  • Receptors, Cytoplasmic and Nuclear / antagonists & inhibitors*
  • Receptors, Cytoplasmic and Nuclear / metabolism
  • Sirtuin 1 / antagonists & inhibitors*
  • Sirtuin 1 / metabolism
  • Structure-Activity Relationship
  • Tumor Cells, Cultured

Substances

  • (R)-4'-methylklavuzon
  • AC133 Antigen
  • Antineoplastic Agents
  • EPCAM protein, human
  • Epithelial Cell Adhesion Molecule
  • Karyopherins
  • Naphthalenes
  • Receptors, Cytoplasmic and Nuclear
  • SIRT1 protein, human
  • Sirtuin 1