Role of the Wnt Signaling Pathway in Keratoacanthoma

The study investigated the role of the Wnt/β-catenin signaling pathway in the development of keratoacanthoma (KA), a type of skin tumor with a growth pattern similar to the hair follicle cycle. The research involved analyzing the expression of Wnt signaling proteins (β-catenin, Lef1, Sox9, and Cyclin D1) in 67 formalin-fixed, paraffin-embedded tissue samples of KAs using immunohistochemistry. The results showed that the majority of KAs expressed Sox9 and Cyclin D1, but not nuclear-localized β-catenin or Lef-1, with no significant difference between young and old KAs. A significant association was found between Ki67 and Cyclin D1 proteins (P = .008). The conclusion drawn from the study was that the Wnt signaling pathway does not play a significant role in the biogenesis of human KA, and that the overexpression of Sox9 may indicate inhibition of Wnt signaling. Sox9 and Cyclin D1 were suggested to be proliferation markers likely activated by alternative signaling pathways.