Houttuynia cordata Thunb extract induces apoptosis through mitochondrial-dependent pathway in HT-29 human colon adenocarcinoma cells

Oncol Rep. 2009 Nov;22(5):1051-6. doi: 10.3892/or_00000535.

Abstract

The Houttuynia cordata Thunb (HCT) extract has been used as a traditional Chinese herb medicine and as well as an effective drug for treating allergic inflammation for thousands of years. In this study, we investigated the anti-cancer activity of HCT and its molecular mechanisms in the human colon adenocarcinoma cell line HT-29. HCT inhibited HT-29 cell viability in a dose- and time-dependent manner by MTT assay. Treatment with 450 microg/ml of HCT for 48 and 72 h led to DNA damage and apoptosis by DAPI staining and comet assay. HCT increased reactive oxygen species production and decreased the levels of mitochondria membrane potential (MMP) in HT-29 cells by flow cytometry analysis. HCT caused the release of cytochrome c, Apaf-1, pro-caspase-9 and AIF from mitochondria via a decrease of the MMP. The decrease of MMP was then associated with a decrease in the ratio of Bax/Bcl-2 and activation of caspase-9 and -3 by Western blotting and caspase activity assay. Caspase-9 and -3 inhibitors almost completely suppressed HCT-induced caspase-9 and -3 activities. Our results demonstrated that the HCT-induced apoptosis in human colon adenocarcinoma cell line HT-29 might be related to a mitochondrial-dependent pathway.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenocarcinoma / metabolism
  • Adenocarcinoma / pathology*
  • Apoptosis / drug effects*
  • Blotting, Western
  • Caspases / metabolism
  • Cell Proliferation / drug effects
  • Colonic Neoplasms / metabolism
  • Colonic Neoplasms / pathology*
  • Comet Assay
  • DNA Damage / drug effects
  • Dose-Response Relationship, Drug
  • Drugs, Chinese Herbal / pharmacology*
  • Flow Cytometry
  • Humans
  • Matrix Metalloproteinase 9 / metabolism
  • Membrane Potential, Mitochondrial / drug effects
  • Mitochondria / metabolism*
  • Reactive Oxygen Species / metabolism
  • Signal Transduction
  • Time Factors
  • Tumor Cells, Cultured

Substances

  • Drugs, Chinese Herbal
  • Reactive Oxygen Species
  • plant extract, Houttuynia cordata
  • Caspases
  • Matrix Metalloproteinase 9