Regulation of HAND2 Expression by LncRNA HAND2-AS1 in Ovarian Endometriosis Involving DNA Methylation

Study on 20-hydroxyprogesterone: Chiral resolution, content determination and progesterone-like activity

20-hydroxyprogesterone (20-DHP) is a natural metabolite of progesterone which occurs with two diastereoisomers: 20α-DHP and 20β-DHP. They have drawn attention for their progesterone-like activity since the middle of the 20th century. However, the literature from that era bears witness to a lack of consensus regarding their specific effects. Considered that their stereoisomerism differences, it is essential to investigate their biological activities in vivo separately. In this study, we presented a chemical synthesis technique that yielded highly pure samples of 20α-DHP and 20β-DHP, and performed simultaneous content analysis. Subsequently, we examined and contrasted the progesterone-like properties of 20α-DHP, 20β-DHP, and a 1:1 mixture of 20α-DHP and 20β-DHP. The Morphological observations of the endometrium were conducted via Haematoxylin-eosin staining. Serum hormone levels were measured using enzyme-linked immunosorbent assays. Furthermore, real-time fluorescence quantitative polymerase chain reaction and immunohistochemistry were employed to analyse the relevant mRNA and protein expression, respectively. Our comparison revealed that 20α-DHP and P4 share identical progesterone-like actions, while 20β-DHP exhibits partial similarity. The progesterone activity varied when the two were combined in a 1:1 ratio.

The Long Non-Coding RNA Gene AC027288.3 Plays a Role in Human Endometrial Stromal Fibroblast Decidualization

During the secretory phase of the menstrual cycle, endometrial fibroblast cells begin to change into large epithelial-like cells called decidual cells in a process called decidualization. This differentiation continues more broadly in the endometrium and forms the decidual tissue during early pregnancy. The cells undergoing decidualization as well as the resulting decidual cells, support successful implantation and placentation during early pregnancy. This study was carried out to identify new potentially important long non-coding RNA (lncRNA) genes that may play a role in human endometrial stromal fibroblast cells (hESF) undergoing decidualization in vitro, and several were found. The expression of nine was further characterized. One of these, AC027288.3, showed a dramatic increase in the expression of hESF cells undergoing decidualization. When AC027288.3 expression was targeted, the ability of the cells to undergo decidualization as determined by the expression of decidualization marker protein-coding genes was significantly altered. The most affected markers of decidualization whose expression was significantly reduced were FOXO1, FZD4, and INHBA. Therefore, AC027288.3 may be a major upstream regulator of the WNT-FOXO1 pathway and activin-SMAD3 pathways previously shown as critical for hESF decidualization. Finally, we explored possible regulators of AC027288.3 expression during human ESF decidualization. Expression was regulated by cAMP and progesterone. Our results suggest that AC027288.3 plays a role in hESF decidualization and identifies several other lncRNA genes that may also play a role.

Activation of HAND2-FGFR signaling pathway by lncRNA HAND2-AS1 in adenomyosis†

Heart and neural crest derivatives expressed transcript 2 (HAND2) is a critical mediator of progesterone action in endometrial stromal cells. Silencing of Hand2 expression in mouse uterus leads to an unopposed FGFR-mediated action that causes female mice infertility. To investigate the involvement of HAND2-FGFR signaling in pathogenesis of adenomyosis, immunohistochemistry, in situ hybridization, and quantitative real-time PCR were employed to assess gene expression in the normal endometrium, the paired eutopic endometrium and ectopic lesions obtained from women with adenomyosis. DNA methylation in the regions of HAND2 promoter and the first exon was also monitored in these samples. Our results revealed that HAND2 expression were dramatically reduced, but FGF9 expression and FGFR-ERK1/2-mediated MAPK signaling pathway were enhanced in the eutopic endometrium and ectopic lesions of patients with adenomyosis compared to the normal controls. Interestingly, expression of HAND2-AS1, a long noncoding RNA that resides adjacent to HAND2 in genome, was also reduced in adenomyosis. DNA methylation analysis revealed that the bidirectional promoter between HAND2 and HAND2-AS1, and the first exon of HAND2 gene was heavily methylated in the eutopic endometrium and the ectopic lesions of adenomyosis. To investigate the regulation of gene expression by HAND2-AS1, HAND2-AS1 expression was silenced in human endometrial stromal cells. In contrast to the downregulation of HAND2 in response to HAND2-AS1 silencing, FGF9 expression was augmented significantly. Endometrial stromal cells lacking HAND2-AS1 exhibited enhanced proliferation and migration potentials. Collectively, our studies revealed a new molecular mechanism by which HAND2-AS1 is involved in the pathogenesis of adenomyosis via modulating HAND2-FGFR-mediated signaling.