Whole-genome microarray and targeted analysis of angiogenesis-regulating gene expression (ENG, FLT1, VEGF, PlGF) in placentas from pre-eclamptic and small-for-gestational-age pregnancies.

OBJECTIVE: To compare the placental pathology associated with pre-eclampsia (PE) and/or fetal growth restriction, the transcriptomes of placental tissues from PE and small-for-gestational-age (SGA) pregnancies were explored. In addition, a targeted analysis of angiogenesis-regulating gene expression was performed.
METHODS: Whole-genome microarray analysis was performed on placental tissue from gestational age-matched PE (n = 10), SGA (n = 8) and PE + SGA (n = 10) pregnancies. The expression of genes regulating angiogenesis (endoglin (ENG), fms-related tyrosine kinase 1 (FLT1), vascular endothelial growth factor (VEGF) and placental growth factor (PlGF)) was analyzed by quantitative real time reverse transcriptase polymerase chain reaction (qRT-PCR).
RESULTS: Microarray analysis did not reveal any significant differences between groups. However, an increased expression of ENG and FLT1 was detected by qRT-PCR in the PE + SGA group.
CONCLUSIONS: The placental transcriptome did not differ between groups, although an increased anti-angiogenic gene expression in PE + SGA was observed with qRT-PCR analysis. Based on this, we conclude that although microarray technology may represent a powerful tool in generating new hypothesis in complex fields, it may not be sensitive enough to detect subtle changes in gene expression.