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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
PubMed

Insights

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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