Oral pyogenic granulomas show MAPK/ERK signaling pathway activation, which occurs independently of BRAF, KRAS, HRAS, NRAS, GNA11, and GNA14 mutations

Abstract

Background: Pyogenic granuloma (PG) is a benign nodular lesion with a prominent vascular component which may affect different sites. Recently, BRAF, KRAS, HRAS, NRAS, GNA11, and GNA14 mutations were reported on PGs of the skin. The present study assessed the role of the MAPK/ERK pathway in oral PG pathogenesis.

Methods: Mutations in hotspot regions of genes involved in the MAPK/ERK pathway activation were investigated by Sanger sequencing. The expression of phospho-ERK1/2 was evaluated by immunohistochemistry.

Results: Oral PGs did not show mutations in the sequenced regions of the genes BRAF, KRAS, HRAS, NRAS, GNA11, or GNA14. Our results also showed activation of the MAPK/ERK pathway demonstrated by phospho-ERK1/2 immunohistochemical positivity.

Conclusions: Although oral PG shows MAPK/ERK pathway activation, the driver molecular event remains to be elucidated.

Keywords: MAPK; RAS; capillary hemangioma; oncogene; pyogenic granuloma.