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Updated: Jun 11, 2026
12:37
Pharmacologic Induction of Epidermal Melanin and Protection Against Sunburn in a Humanized Mouse Model
Published on: September 7, 2013
Kaempferol inhibits UVB-induced COX-2 expression by suppressing Src kinase activity
Kyung Mi Lee1, Ki Won Lee, Sung Keun Jung
1The Hormel Institute, University of Minnesota, 801 16th Avenue NE, Austin, MN 55912, USA.
Biochemical Pharmacology
|July 6, 2010
Summary
Kaempferol, a flavonoid, effectively inhibits UVB-induced skin inflammation and cancer development by blocking Src kinase activity. This natural compound shows promise as a chemopreventive agent against nonmelanoma skin cancer.
Area of Science:
- Photocarcinogenesis
- Molecular Biology
- Chemoprevention
Background:
- Ultraviolet (UV) radiation, particularly UVB, is a major risk factor for nonmelanoma skin cancer.
- Flavonoids like kaempferol possess anti-inflammatory and anti-oxidative properties, but their role in UVB-induced skin cancer is not well understood.
Purpose of the Study:
- To investigate the effects of kaempferol on UVB-induced skin inflammation and photo-carcinogenesis.
- To elucidate the molecular mechanisms underlying kaempferol's action against UVB damage.
Main Methods:
- Cellular assays using JB6 P+ mouse skin cells to assess protein expression and transcriptional activity.
- Kinase assays (in vitro and ex vivo) to evaluate Src kinase activity.
- In vivo mouse skin studies and molecular docking to confirm kaempferol's interaction with Src.
Main Results:
- Kaempferol suppressed UVB-induced cyclooxygenase-2 (COX-2) and activator protein-1 (AP-1) activation.
- It inhibited the phosphorylation of mitogen-activated protein kinases (MAPKs) but not upstream Src.
- Kaempferol directly inhibited Src kinase activity by competing with ATP binding, as confirmed by in vitro, ex vivo, and docking studies.
Conclusions:
- Kaempferol acts as a potent chemopreventive agent against UVB-induced skin cancer.
- Its mechanism involves the direct inhibition of Src kinase activity, thereby reducing downstream inflammatory signaling pathways.
- Kaempferol represents a promising therapeutic candidate for preventing skin cancer development.
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