Expression profiles of candidate microRNAs in the peripheral blood leukocytes of patients with early- and late-onset preeclampsia versus normal pregnancies

Objectives: Maternal leucocytes play an important role in the pathogenesis of preeclampsia (PE). Circulating microRNAs (miRNAs) are small, noncoding RNA molecules. The purpose of this study was to investigate miR-518b, miR-155-5p, and miR-21-3p in the peripheral blood leukocytes of patients with PE, compared to controls. Study design: Using real-time quantitative PCR method, the selected miRNAs which have been associated with PE were examined from early-onset PE (EOPE) (< 34 weeks) (n = 48), late-onset PE (LOPE) (>= 34 weeks) (n = 48), total cases of PE (n = 96), and healthy controls (n = 52). Main outcome measures: The relative expression of the target miR in patient samples was compared to the calibrator and the results were expressed as relative quantification values. Results: Gestational age (GA) was significantly different between PE and controls. Univariate logistic regression analysis adjusted for GA at blood draw were fit to compare miR-518b, miR-155-5p, and miR-21-3p between PE and controls. The expression of miR-518b, miR-155-5p, and miR-21-3p were not significantly different in PE, compared to controls. The expression of miR-518b was upregulated in the EOPE and LOPE group, compared to controls, and the area under the receiver operating characteristic curve (AUC) of miR-518b was 0.65 and 0.62, respectively. miR-518b was positively correlated with WBC count, platelet count, serum levels of AST, ALT, LDH in EOPE. miR-21-3p expression level was negatively correlated with body mass index at blood draw and systolic blood pressure in the LOPE group. Conclusions: Increased miR-518b expression levels were found to be associated with EOPE and LOPE.