Investigation of expression of small ubiquitin-like modifier (SUMO) 1 and DNA methyltransferase (DNMT) 2 in pregnant women with preeclampsia

Subject: The aim was to investigate the expression of DNA methyltransferase 2 (DNMT2) and Small Ubiquitin-Like Modifier 1 (SUMO1) expression levels in preeclamptic pregnant women and to shed light on the role of epigenetic mechanisms in the etiopathogenesis of preeclampsia. Material and Method: A total of 78 pregnants, including 16 early-onset preeclamptic (EOPE), 25 late-onset preeclamptic (LOPE) and 37 normotensive control pregnant women, have been evaluated. Expression of placental DNMT2 and SUMO1 have been examined by using immunohistochemical staining technique. Results: While nuclear and cytoplasmic SUMO1 levels and cytoplasmic DNMT2 levels were significantly higher in the preeclampsia group (p<0.05, p<0.05, p<0.05, respectively), no significant difference was observed between the groups in terms of nuclear DNMT2 levels (p>0.05). A significant difference was found between the EOPE group and the control group in terms of SUMO1 cytoplasmic, SUMO1 nuclear and DNMT2 cytoplasmic levels (p<0.05, p<0.05, p<0.05, respectively). While there was a significant positive correlation between nuclear and cytoplasmic SUMO1 levels and cytoplasmic DNMT2 level and the amount of proteinuria (p<0.05, p<0.05, p<0.05, respectively), a significantly negative correlation was found with the delivery time (p<0,001). Conclusion: We determined that nuclear and cytoplasmic SUMO1 levels and cytoplasmic DNMT2 levels were significantly higher in the preeclampsia group compared to the control group. The results underline the role of these epigenetic modifications in the pathogenesis of preeclampsia.