Dysregulation of Placental Functions and Immune Pathways in Complete Hydatidiform Moles

We analyzed high-dimensional RNA data to characterize molecular features of complete hydatidiform moles (CHMs) and corresponding pathologic pathways. CHMs and first trimester placentas were collected, histopathologically examined, then flash-frozen. Frozen CHMs and control placentas were subjected to RNA-Seq, with resulting data and published placental RNA-Seq data subjected to bioinformatics analyses. Of the 14,022 protein-coding genes expressed in all samples, 3729 were differentially expressed (DE) in CHMs of which 72% were up-regulated. DE genes were enriched in placenta-specific genes (OR = 1.88, p = 0.0001) of which 79% were down-regulated, imprinted genes (OR = 2.38, p = 1.54 × 10−6), and immune genes (OR = 1.82, p = 7.34 × 10−18), of which 73% were up-regulated. DNA methylation enzymes and histone demethylases were dysregulated. “Cytokine–cytokine receptor interaction” was the most impacted of 38 dysregulated pathways, among which 17 were immune-related pathways. Frozen complete hydatidiform moles and control placentas were subjected to RNA-Seq, with resulting RNA-Seq data subjected to bioinformatics analyses.