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09:17
Co-immunoprecipitation Assay Using Endogenous Nuclear Proteins from Cells Cultured Under Hypoxic Conditions
Published on: August 2, 2018
Honokiol inhibits hypoxia-inducible factor-1 pathway
Keng-Li Lan1, Keng-Hsin Lan, Meei-Ling Sheu
1Cancer Center, Taipei Veterans General Hospital, Taipei, Taiwan. kllan@vghtpe.gov.tw
International Journal of Radiation Biology
|April 9, 2011
Summary
Honokiol inhibits hypoxia-inducible factor-1α (HIF-1α) and tumor growth. This natural compound enhances radiation therapy
Area of Science:
- Oncology
- Molecular Biology
- Pharmacology
Background:
- Hypoxia-inducible factor-1α (HIF-1α) is crucial in tumor response to hypoxia.
- HIF-1α activity influences tumor progression and treatment resistance.
Purpose of the Study:
- To investigate honokiol's inhibitory effect on HIF-1α activity.
- To evaluate honokiol's impact on tumor growth, particularly in combination with radiation therapy.
Main Methods:
- Assessed honokiol's effect on hypoxia-responsive element (HRE) luciferase activity and HIF-1α accumulation.
- Utilized immunohistochemistry and in vivo bioluminescence to study HIF-1α levels in tumors.
- Evaluated the in vivo radiosensitizing effects of honokiol on murine colon carcinoma (CT26) xenografts.
Main Results:
- Honokiol suppressed HRE-luciferase activity and decreased HIF-1α accumulation.
- In vivo studies demonstrated honokiol's non-invasive monitoring of HIF-1α inhibition in tumors.
- Combination of honokiol and irradiation synergistically delayed CT26 tumor growth.
Conclusions:
- Honokiol acts as a HIF-1α inhibitor, reducing HIF-1α protein levels and suppressing hypoxia-related signaling.
- Honokiol enhances the therapeutic efficacy of radiation in preclinical cancer models.
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