Mutations of the BRAF gene in benign and malignant melanocytic lesions.
A single-point mutation in exon 15 of the BRAF gene has recently been reported in a high percentage in cultured melanoma cells and in 6 of 9 primary melanomas examined. To evaluate the impact of the T1796A BRAF mutation, we screened primary melanomas, various types of nevi and lesions where a melanoma developed in an underlying nevus. We could detect the mutation in 28 of 97 (29%) melanomas and in 39 of 187 (21%) nevi, including blue nevi (0/20) and Spitz nevi (0/69), which did not carry the mutation. In melanomas with an underlying nevus, either the mutation was present in both the laser-microdissected nevus cells and the laser-microdissected melanoma cells (3/14) or both lesions were negative for the BRAF mutation except one case. In conclusion, mutations in exon 15 of the BRAF gene are nonspecific for progression of a nevus to a melanoma. Other so far unknown cofactors seem to be of importance.
Yazdi
Amir S
AS
Department of Dermatology, Ludwig-Maximilians-University, Munich, Germany.
Palmedo
Gabriele
G
Flaig
Michael J
MJ
Puchta
Ursula
U
Reckwerth
Andrea
A
Rütten
Arno
A
Mentzel
Thomas
T
Hügel
Heino
H
Hantschke
Markus
M
Schmid-Wendtner
Monika-Hildegard
MH
Kutzner
Heinz
H
Sander
Christian A
CA
D005091:Exons; D006801:Humans; D008545:Melanoma / Q000235:genetics* / Q000473:pathology; D009506:Nevus / Q000235:genetics* / Q000473:pathology; D017354:Point Mutation; D019908:Proto-Oncogene Proteins c-raf / Q000235:genetics*; D012878:Skin Neoplasms / Q000235:genetics* / Q000473:pathology
D019908:Proto-Oncogene Proteins c-raf