The BRAF p.V600E mutation is a common event in ameloblastomas but is absent in odontogenic keratocysts

Abstract Background Odontogenic keratocysts (OKCs) are jaw lesions with a tendency to recur. PTCH1 gene mutations are common events in most OKCs; however, other genetic alterations underlying OKC pathogenesis have not yet been elucidated. BRAF p.V600E mutations have recently been detected in some odontogenic tumors, such as ameloblastoma and ameloblastic fibroma, although their involvement in OKC is still unclear. In this study, we aimed to clarify the presence and/or frequency of BRAF p.V600E mutations in OKCs. Methods Thirty-five cases of OKCs, 13 of which were associated with Gorlin syndrome, were evaluated for BRAF p.V600E mutations by direct sequencing of the formalin-fixed paraffin-embedded and frozen tissue samples. Seventeen cases of ameloblastoma and six cases of dentinogenic ghost cell tumor were also included in this study for comparative purposes. Results BRAF p.V600E mutations were not detected in any of the OKCs or dentinogenic ghost cell tumors. In contrast, 14 of 17 (82.35%) cases of ameloblastoma were proven to harbor BRAF p.V600E mutations. Conclusion BRAF p.V600E mutations were frequent in ameloblastomas, as previously reported, but were absent in OKCs and dentinogenic ghost cell tumors. These results further confirmed the noninvolvement of BRAF in OKCs and suggested different pathogenic mechanisms involved in various odontogenic lesions.