Silymarin suppresses HepG2 hepatocarcinoma cell progression through downregulation of Slit-2/Robo-1 pathway

Pharmacol Rep. 2020 Feb;72(1):199-207. doi: 10.1007/s43440-019-00040-x. Epub 2020 Jan 8.

Abstract

Background: 14 million people are diagnosed with new cancer and approximately 8 million people die from cancer every year. Hepatocellular carcinoma is the most common type of liver cancer and covers almost 5-6% of cancer deaths worldwide. Silybum marianum, a plant that contains silymarin, has been used traditionally in the treatment of liver diseases for centuries. The antioxidant, anti-inflammatory and anti-fibrotic anti-cancer properties of silymarin have been demonstrated in several studies in vivo and in vitro. The Slit/Robo signaling pathway plays a role in many processes such as neurogenesis, angiogenesis, cell proliferation, cell movement, cancer progression, cell invasion, migration and metastasis. In this study, we aimed to investigate the effects of silymarin on HepG2 Hepatocellular carcinoma cells on Slit-2/Robo-1 signaling pathway and CXCR-4 which plays a role in the metastasis process.

Methods: HepG2 Hepatocellular carcinoma cells were used in the study. Different doses of silymarin's effect on HepG2 cells were observed by hematoxylin and eosin staining. Immunoblotting techniques were used to test the expression of Slit-2/Robo-1 and CXCR4 protein level. Immunocytochemistry was used to visualize the localization of Slit-2/Robo-1 and CXCR4 protein within the cells.

Results: Silymarin caused apoptosis in HepG2 cells, decreased the level of CXCR-4 protein dose-dependently, and decreased the Slit-2/Robo-1 protein level at low doses and increased it at high doses.

Conclusions: Silymarin doses showed anti-carcinogenic, anti-metastatic and apoptotic effects in a dose-dependent manner on HepG2 cells through the Slit-2/Robo-1 pathway.

Keywords: HepG2 cells; Hepatocarcinoma; Silymarin; Slit/Robo pathway.

MeSH terms

  • Antineoplastic Agents, Phytogenic / administration & dosage
  • Antineoplastic Agents, Phytogenic / pharmacology*
  • Apoptosis / drug effects
  • Carcinoma, Hepatocellular / drug therapy*
  • Carcinoma, Hepatocellular / pathology
  • Cell Movement / drug effects
  • Cell Proliferation / drug effects
  • Disease Progression
  • Dose-Response Relationship, Drug
  • Down-Regulation / drug effects
  • Hep G2 Cells
  • Humans
  • Intercellular Signaling Peptides and Proteins / genetics
  • Liver Neoplasms / drug therapy*
  • Liver Neoplasms / pathology
  • Nerve Tissue Proteins / genetics
  • Receptors, Immunologic / genetics
  • Roundabout Proteins
  • Signal Transduction / drug effects
  • Silymarin / administration & dosage
  • Silymarin / pharmacology*

Substances

  • Antineoplastic Agents, Phytogenic
  • Intercellular Signaling Peptides and Proteins
  • Nerve Tissue Proteins
  • Receptors, Immunologic
  • Silymarin
  • Slit homolog 2 protein