The BRCA1 Expression in Placenta of Normal and Fetal Growth Restriction

Moon, J S; Jeong, J H; Park, C S; Yang, S H; Roh, J R; Song, S Y

Abstract

OBJECTIVE
BRCA1, the breast and ovarian cancer susceptibility gene, is regarded as not only a tumor suppressor gene but regulator of cell growth and differentiation. We hypothesized that there is a relationship between BRCA1 expression and growth and differentiation of trophoblast.
METHODS
Twenty placental samples were collected from 5 fetal growth-restricted term pregnancies and 15 normal growth pregnancies at different gestational ages [from 9th week of gestational age to term ; 5 samples from each trimester]. Immunohistochemistry and western blotting were performed for identifying the expression of BRCA1 protein.
RESULTS
The expression of BRCA1 were detected on all normal placentas. We could not find any remarkable difference of BRCA1 expression according to gestational age on normal placentas. In growth-restricted placenta, the staining intensity was diminished more than 30% and the number of stained cells were decreased more than 20% by immunohistochemistry, and BRCA1 protein expression was decreased about 30% on western blotting compared with normal placenta.
CONCLUSION
These results revealed that the expression of BRCA1 gene is a constant finding irrespective of gestational ages and decreased in the placenta taken from growth restricted fetuses compared with normal fetuses. It suggests that BRCA1 may play a role in trophoblast differentiation and be related to the pathophysiologic mechanism of fetal growth restriction.