Figure 2
Hierarchical cluster analysis and validation of differentially expressed microRNAs.
46 differentially expressed microRNAs were selected using the following criteria: q value ≤0.05; fold change ≥1.5 or ≤0.66. The relative expression level was log transformed. Each column represents a placental sample from a pregnant control without preeclampsia (C1–C9) or with preeclampsia (P1–P10). The colour bar in the upper left indicates high expression (red) or low expression (green) (A). Validation of differentially expressed microRNAs by qRT-PCR. 2 down-regulated microRNAs (B) and 8 up-regulated microRNAs (C) are validated by qRT-PCR with independent control placentas (n = 20) and PE placentas (n = 22). The relative expression of each unique miRNA was normalized by the value of the U6 gene. We normalized the control as 1 by dividing each value by the average value of the control group. PE/Control–HTS indicates the fold change of PE placental microRNA expression level relative to the control as demonstrated by HTS. The mean raw ΔCT (CT,miRNA − CT,U6) values of each miRNA were shown on top of the bars. Data are shown as the mean ± S.E.M. Significant differences were determined by 2-tailed Student’s t test or the Mann-Whitney test. ***P < 0.001, **P < 0.01, *P < 0.05.
