The profile analysis of circular RNAs in human placenta of preeclampsia

Abstract

A total of 70 pregnant women were recruited for this study, including 35 early onset preeclampsia (PE) and 35 normal pregnant women. By RNA sequencing, the circular RNA (circRNAs) in placenta were identified. Differentially expressed circRNAs were bioinformatics analyzed with gene ontology, Kyoto Encyclopedia of Genes and Genomes, and circRNA–miRNA interaction prediction. Quantitative real time polymerase chain reaction(qRT-PCR) assay was used to verify the results. Compared with the normal pregnant women, there were 49 circRNAs differentially expressed in the placental tissue of PE women, including two circRNAs were up-regulated and 47 were down-regulated. Ten differentially expressed circRNAs were selected for validation by qRT-PCR, among which results of three circRNAs, circRNA_3286, circRNA_5593, and circRNA_3800, were consistent with the sequencing. According to the bioinformatic prediction, we speculate that these circRNAs may be involved in some cellular regulatory functions in PE through their targeted miRNAs. We also evaluated the expression of circRNA_3286 in plasma to be used as a potential biomarker for PE; in vitro Transwell assay shown transfected with si-circ-3286 significantly reduced invasion in HTR8/Svneo cells. In conclusion, we displayed a preliminary landscape of circRNA differential expression in PE and discussed their possible regulatory mechanisms. This study revealed a new insight into the molecular mechanism of PE. Impact statement The abnormal expression of many regulatory factors may be involved in the development of PE. circRNAs are proved to have a series of important biological functions; however, reports about circRNA and PE are rare. In this work, we evaluated the profile analysis of circRNAs in human placenta of PE by RNA-seq and found some newly differentially expressed circRNAs which might be involved in PE. Combined with bioinformatics analysis, their possible functions were preliminarily discussed.