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Luteolin induces apoptosis via death receptor 5 upregulation in human malignant tumor cells

Mano Horinaka1, Tatsushi Yoshida, Takumi Shiraishi

  • 1Department of Molecular-Targeting Cancer Prevention, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan.

Oncogene
|July 12, 2005
PubMed

Insights

Luteolin, a flavonoid, triggers cancer cell death by increasing death receptor 5 (DR5). This discovery offers potential for new cancer therapies targeting DR5 signaling pathways.

Area of Science:

  • Molecular Biology
  • Biochemistry
  • Cancer Research

Background:

  • Luteolin, a natural flavonoid, exhibits anticancer properties by inducing apoptosis.
  • The precise molecular mechanisms underlying luteolin's apoptotic effects remain largely unelucidated.

Purpose of the Study:

  • To investigate the novel molecular mechanisms of luteolin-induced apoptosis.
  • To determine the role of death receptor 5 (DR5) in luteolin's anticancer activity.

Main Methods:

  • Investigated luteolin's effects on cancer cell apoptosis and DR5 expression.
  • Utilized siRNA to suppress DR5 expression and assessed its impact on apoptosis.
  • Employed human recombinant DR5/Fc to evaluate its inhibitory effect on luteolin-induced apoptosis.

Main Results:

  • Luteolin significantly upregulated DR5 expression, leading to Bcl-2-interacting domain cleavage and caspase activation (caspase-8, -10, -9, and -3).
  • siRNA-mediated suppression of DR5 diminished luteolin-induced caspase activation and apoptosis.
  • Recombinant DR5/Fc inhibited luteolin-induced apoptosis.
  • Luteolin did not induce DR5 expression or apoptosis in normal human peripheral blood mononuclear cells.

Conclusions:

  • Luteolin-induced apoptosis is mediated through the upregulation of death receptor 5 (DR5).
  • DR5 plays a crucial role in mediating luteolin's apoptotic effects in cancer cells.
  • Luteolin holds promise as a potential therapeutic agent for cancer treatment, leveraging DR5-mediated apoptosis.

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