Schisandrin B Suppresses Colon Cancer Growth by Inducing Cell Cycle Arrest and Apoptosis: Molecular Mechanism and

Vanessa Anna Co1, Hani El-Nezami1,2, Yawen Liu3

  • 1School of Biological Sciences, Faculty of Science, Kadoorie Biological Sciences Building, The University of Hong Kong, Pokfulam Hong Kong.

Insights

Schisandrin B (Sch B) effectively inhibits colon cancer growth by inducing apoptosis. This natural compound activates the unfolded protein response via CHOP, offering a promising therapeutic avenue for colon cancer treatment.

Area of Science:

  • Oncology
  • Molecular Biology
  • Pharmacology

Background:

  • Colon cancer is a leading cause of cancer-related deaths globally.
  • Existing therapies for colon cancer have limitations, necessitating novel treatment strategies.
  • Schisandrin B (Sch B), derived from *Schisandra chinensis*, shows potential anticancer activity, but its mechanism in colon cancer is unclear.

Purpose of the Study:

  • To investigate the antitumorigenic effects of Schisandrin B (Sch B) in colon cancer.
  • To elucidate the molecular mechanisms underlying Sch B's therapeutic action.
  • To evaluate Sch B's efficacy in preclinical colon cancer models.

Main Methods:

  • Utilized Raman spectroscopy, RNA-sequencing (RNA-seq), computational docking, and molecular/cellular experiments.
  • Assessed *in vitro* effects on human colon cancer cell lines.
  • Evaluated *in vivo* efficacy using a mouse xenograft model.

Main Results:

  • Sch B significantly reduced colon cancer cell proliferation and induced apoptosis.
  • Sch B activated the unfolded protein response by upregulating and interacting with CHOP.
  • CHOP knockdown diminished Sch B's effects on cell viability and apoptosis, confirming CHOP's role.
  • Sch B inhibited colon tumor growth in a mouse xenograft model.

Conclusions:

  • Schisandrin B demonstrates significant antitumorigenic effects against colon cancer both *in vitro* and *in vivo*.
  • The mechanism involves Sch B-induced apoptosis mediated by the CHOP-dependent unfolded protein response.
  • These findings support Sch B as a potential candidate for clinical trials in colon cancer patients.

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