Different Expression and Clinical Significance of DNA Methyltransferases in the Chorionic Villi of Early Embryo Growth Arrest

GUO Wei-wei; GAO Jing; ZHOU Lei; HUANG Wei-qing; KONG Qing-nuan

Abstract：Objective:To study the expression of DNMT1, DNMT3A, DNMT3B and DNMT3L mRNA and protein in the chorionic villi of early embryo growth arrest and explore its clinical significance. Methods:We randomly selected 40 women as observational group in which were diagnosed with early embryo growth arrest by B ultrasound and accepted complete curettage of uterine cavity after visiting the Obstetrical Department of the Qingdao Municipal Hospital between January 2013 and June 2014, during the same period, select another 40 women who performed induced abortion with normal early pregnancy as control group.①Real-time quantitative PCR (qRT-PCR) was used on the normal groups (40 cases) and the early embryo growth arrest group (40 cases) to quantitatively determine DNMT1, DNMT3A, DNMT3B and DNMT3L mRNA expression in the chorionic villi tissues. ②Streptavidin- Perosidase (SP) immunochemistry and Western blot were performed on the two groups to detect the expression and distribution of DNMT1, DNMT3A, DNMT3B and DNMT3L. Results: ①qRT-PCR showed there were no statistically significant difference of DNMT1, DNMT3A, DNMT3B and DNMT3L expression in two groups (P>0.05).②Immuno-chemistry showed DNMTs were predominately distributed on the villous trophoblasts which the cytoplasm and nuclear had varying degrees of positive staining. And semi-quantitative analysis indicated that the expression of DNMT3A of early embryo growth arrest was significantly lower, compared with that of the normal group (P<0.05).③Western blot also showed expression of DNMT3A of early embryo growth arrest was lower, differences between the two groups were statistical significance (P<0.05).④There was no significant correlation between DNMT3A and DNMT1, DNMT3B, DNMT3L in the chorionic villi of early embryo growth arrest (all P>0.05). Conclusions:The lower expression of the DNMT3A protein might be involved in the pathogenesis of early embryo growth arrest.