Concanavalin A induces autophagy in hepatoma cells and has a therapeutic effect in a murine in situ hepatoma model

Authors

  • Chih-Peng Chang,

    1. Institute of Basic Medical Sciences, National Cheng Kung University, Tainan, Taiwan, Republic of China
    Search for more papers by this author
  • Ming-Cheng Yang,

    1. Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan, Republic of China
    Search for more papers by this author
  • Hsiao-Sheng Liu,

    1. Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan, Republic of China
    Search for more papers by this author
  • Yee-Shin Lin,

    1. Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan, Republic of China
    Search for more papers by this author
  • Huan-Yao Lei

    Corresponding author
    1. Institute of Basic Medical Sciences, National Cheng Kung University, Tainan, Taiwan, Republic of China
    2. Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan, Republic of China
    • Department of Microbiology and Immunology, College of Medicine, National Cheng Kung University, Tainan, Taiwan, Republic of China
    Search for more papers by this author
    • fax: 886-6-2097825


  • Potential conflict of interest: Nothing to report.

Abstract

Concanavalin A (ConA), a lectin with mannose specificity that can induce acute hepatic inflammation, was tested for its therapeutic effect against hepatoma. ConA is cytotoxic or inhibitory to hepatoma cells, which is mediated by the autophagic pathway through mitochondria. Once it was bound to cell membrane glycoproteins, the ConA was internalized and preferentially localized onto the mitochondria. The mitochondria membrane permeability changed, and an autophagic pathway including LC3-II generation, double-layer vesicle, BNIP3 induction, and acidic vesicular organelle formation was induced. Either 3-MA or siRNA for BNIP3 and LC3, but neither beclin-1 nor ATG 5, partially inhibited the ConA-induced cell death. In addition to the autophagy induction, ConA is known to be a T cell mitogen. Using an in situ hepatoma model, ConA can exert an anti-hepatoma therapeutic effect, inhibiting tumor nodule formation in the liver and prolonging survival. Conclusion: ConA can be considered as an anti-hepatoma agent therapeutically because of its autophagic induction and immunomodulating activity. This dual function of ConA provides a novel mechanism for the biological effect of lectin. (HEPATOLOGY 2007;45:286–296.)

Ancillary