Aromatase, CYP1B1 and fatty acid synthase expression in breast tumors of BRCA1 mutation carriers.

Numerous experimental evidence suggest that BRCA1-associated breast carcinomas may have distinct endocrine and metabolic features, however these peculiarities are poorly evaluated in clinical settings. Here we comparatively analyzed for the first time aromatase, estrogen 4-hydroxylase (CYP1B1) and fatty acid synthase immunohistochemical expression in breast tumors obtained from 12 BRCA1 mutations carriers and 22 non-carriers. Aromatase expression was higher in mutation carriers than in sporadic cases (p = 0.04), which confirms the earlier results obtained in cell lines with down-regulated wild-type BRCA1 and corroborates the usage of aromatase inhibitors in such patients. No differences between study groups were found in the expression of CYP1B1 and fatty acid synthase, which does not, however, mitigate the need of further search for manifestations of the excessive genotoxic effects of estrogens and for increased lipogenesis in BRCA1 mutations carriers.