Time and dose-response effects of honokiol on UVB-induced skin cancer development.

Abstract

Honokiol has shown chemopreventive effects in chemically-induced and UVB-induced skin cancer in mice. In this investigation, we assessed the time-effects of a topical low dose of honokiol (30 μg), and then the effects of different honokiol doses (30, 45, and 60 μg) on a UVB-induced skin cancer model to find an optimal dose and time for desirable chemopreventive effects. UVB radiation (30 mJ/cm(2), 5 days/week for 25 or 27 weeks) was used to induce skin carcinogenesis in SKH-1 mice. For the time-response experiment 30 μg honokiol in acetone was applied topically to the animals before the UVB exposure (30 min, 1 h, and 2 h) and after the UVB exposure (immediately, 30 min, and 1 h). Control groups were treated with acetone. For the dose-response study, animals were treated topically with acetone or honokiol (30, 45, and 60 μg) one hour before the UVB exposure. In the time-response experiment, honokiol inhibited skin tumor multiplicity by 49-58% while reducing tumor volumes by 70-89%. In the dose-response study, honokiol (30, 45, and 60 μg) significantly decreased skin tumor multiplicity by 36-78% in a dose-dependent manner, while tumor area was reduced by 76-94%. Honokiol (60 μg) significantly reduced tumor incidence by 40% as compared to control group. Honokiol applied in very low doses (30 μg) either before or after UVB radiation shows chemopreventive effects. Honokiol (30, 45, and 60 μg) prevents UVB-induced skin cancer in a dose-dependent manner. Honokiol can be an effective chemopreventive agent against skin cancer.

• Authors: Ruth F Guillermo, Chandeshwari Chilampalli, Xiaoying Zhang, David Zeman, Hesham Fahmy, Chandradhar Dwivedi
• Journal: Drug discoveries & therapeutics (Drug Discov Ther) Vol. 6 Issue 3 Pg. 140-6 (Jun 2012) ISSN: 1881-7831 [Print] Japan
• PMID: 22890204 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antineoplastic Agents, Phytogenic
• Biphenyl Compounds
• Drugs, Chinese Herbal
• Lignans
• honokiol

Topics

• Animals
• Antineoplastic Agents, Phytogenic (therapeutic use)
• Biphenyl Compounds (therapeutic use)
• Dose-Response Relationship, Drug
• Drugs, Chinese Herbal (therapeutic use)
• Female
• Lignans (therapeutic use)
• Mice
• Mice, Hairless
• Neoplasms, Radiation-Induced (drug therapy, pathology)
• Skin Neoplasms (drug therapy, pathology)
• Tumor Burden (drug effects)
• Ultraviolet Rays
• Weight Gain (drug effects)