Distinct subsets of microRNAs are expressed differentially in the human placentas of patients with preeclampsia.

OBJECTIVE Preeclampsia and small-for-gestational age (SGA) neonates have partially overlapping clinicopathologic features. MicroRNAs (miRNAs) are critical posttranscriptional regulators of gene expression. This study was performed to determine whether preeclampsia and SGA are associated with alterations in placental miRNA expression. STUDY DESIGN Placentas were obtained from patients with (1) preeclampsia (n = 9); (2) SGA (n = 9); (3) preeclampsia + SGA (n = 9); and (4) a control group with spontaneous preterm labor and delivery (PTL; n = 9). The expression of 157 miRNAs was assessed by real-time quantitative reverse transcription-polymerase chain reaction. RESULTS Differential expression between preeclampsia and the control group (miR-210, miR-182) and between preeclampsia + SGA and the control group (miR-210, miR-182*, and others) was found. Gene Ontology analysis of the target genes revealed enrichment for specific biological process categories (antiapoptosis: miR-182; regulation of transcription: miR-210). CONCLUSION This study reports, for the first time, increased expression of specific placental miRNAs in preeclampsia with and without SGA. The findings also provide novel targets for further investigation of the pathophysiology of preeclampsia.