Altered gene expression patterns in intrauterine growth restriction: Potential role of hypoxia

Objective: Placental insufficiency is a primary cause of intrauterine growth restriction (IUGR). In our study, microarray technology was used to identify genes, which may impair placentation resulting in IUGR. Study design: The RNA was isolated from both IUGR term placentas and normal term placentas. Microarray experiments were used to identify differentially expressed genes between the 2 cohorts. Real-time quantitative reverse transcriptase polymerase chain reaction and immunohistochemistry were used in follow-up experiments. Results: Microarray experiments identified increased expression of certain genes including leptin, soluble vascular endothelial growth factor receptor, human chorionic gonadotropin, follistatin-like 3, and hypoxia-inducible factor 2α in the IUGR. Real-time quantitative polymerase chain reaction confirmed these results. Conclusion: The upregulation of soluble vascular endothelial growth factor receptor and hypoxia-inducible factor 2α at this period in pregnancy indicate that placental angiogenesis is altered in IUGR and that hypoxia is a major contributor to maldevelopment of the placental vasculature.