RREB1 amplification, (6p25)
The protein encoded by this gene is a zinc finger transcription factor that binds to RAS-responsive elements (RREs) of gene promoters. Diseases associated with RREB1 include melanoma and substance-induced psychosis. RREB1 is thought to beinvolved in Raf/Ras-mediated cell differentiation, possibly by enhancing the expression of Calcitonin, besides being a repressor of angiotensinogen gene and regulate the transcriptional activity of other cancer-related genes.
FISH is a valuable diagnostic tool to differentiate between benign and malignant melanocytic lesions which provides a high degree of sensitivity and specificity.
To differentiate nevi from melanoma, a panel of 3 probes targeting RREB1 (6p), MYB (6q23) and CCND1 (11q13) genes has been developed. Melanoma is considered if complies with any of the following criteria:
- more than 55% of cells with more copies of RREB1 (6p25) than of Cep6 (6p25>Cep6)
- more than 29% of cells with more than 2 RREB1 (6p25) signals
- more than 40% of cells with fewer copies of MYB (6q23) than of Cep6 (6q23<Cep6)
- more than 38% of cells with more than 2 copies of CCND1 (11q13)
References
- Gerami P, et al. (2010) Arch Dermatol. 146(3):273-8.
- Abásolo A, et al. (2012) Clin Exp Dermatol. 37(8):838-43.
- Flajollet S, et al. (2009) Immunol. 183(11):6948-59.
- Senetta R, et al. (2012) Histopathology. 60(5):706-14.
