Negative regulators of Wnt signaling pathway SFRP1 and SFRP3 expression in preterm and term pathologic placentas.

Objective: Since Wnt signaling pathway plays a pivotal role in the placental development, we explored the expression of its negative regulators, SFRP1 and SFRP3 proteins in placentas from pathological pregnancies and compared their levels with those in healthy placentas.Methods: Placentas (n=79) were stained for SFRP1, and SFRP3 proteins by immunohistochemistry and their expression levels were quantified by stereological variable of volume density (Vv, mm degrees).Results: Significantly higher expressions of SFRP1 and SFRP3 were found in all investigated groups of term and preterm pathologic placentas as well as in preterm control placentas in comparison with normal-term placentas.Conclusions: Our findings indicate the active involvement of negative Wnt regulators SFRP1/SFRP3 in placental development and important role in pathology of pregnancy.