CCND1 and preeclampsia: As a type of miRNA, roles of miR-155 in preeclampsia were investigated in several previous studies, and were reported to be elevated in preeclampsia (Azizi et al. 2017; Jairajpuri et al. 2017; Gan et al. 2017) and regulate eNOS, cyclin D1, and CYR61 expression levels in placenta (Li et al. 2014; Zhang et al. 2010; Dai et al. 2012; Kim et al. 2017).