MicroRNA-126-5p downregulates BCAR3 expression to promote cell migration and invasion in endometriosis.

Endometriosis (EMs) is an estrogen-dependent multifactorial disease. Inhibition of estrogen in endometrial cells contributes to their failure to form lesions in ectopic sites. However, whether reducing or suppressing the inhibitory effect of estrogen results in the establishment of ectopic lesions remains unclear. The BCAR3 gene induces estrogen resistance in estrogen-dependent breast cancer cells and promotes cell migration, invasion, and epithelial-mesenchymal transition (EMT). However, the expression of BCAR3 in endometriosis and its effect on endometrial cell function and the anti-estrogen effect of endometriosis have not been reported. These issues are addressed in the present study. The study included 32 cases of ectopic endometrium and eutopic endometrium in patients with endometriosis and 31 cases of normal endometrium as controls. The expression of BCAR3 and microRNA (miR)-126-5p was detected by real-time PCR, immunohistochemistry, and western blotting. The effects of BCAR3 and miR-126-5p on the morphology and biological behavior of eutopic endometrial cells were verified using lentivirus overexpression and a vector knockdown model, the CCK-8 assay, Transwell experiments, and estrogen intervention experiments using primary cultures of epithelial and stromal cells. The BCAR3 gene was highly expressed in ectopic endometrium and the eutopic endometrium of patients with endometriosis, and the expression level was higher in stage III-IV patients than in stage I-II patients. In vitro cell experiments showed that miR-126-5p negatively regulated the expression of BCAR3 and its effect on the migration and invasion of stromal cells. Low expression of miR-126-5p and high expression of BCAR3 promoted endometriosis stromal cell migration and invasion. Assessment of EMT in endometriosis compared with eutopic endometrium showed that the expression of vimentin was significantly increased and the expression of E-cadherin was significantly decreased in ectopic endometrium. Estrogen promoted EMT in eutopic endometrial epithelial cells and this effect was reversed by estrogen inhibitors. BCAR3 had no direct effect on EMT and did not act synergistically with estrogen on promoting EMT. miR-126-5p negatively regulated BCAR3 expression in eutopic endometriosis, enhanced the migration and invasion of endometrial cells, and promoted the occurrence of endometriosis. BCAR3 did not induce EMT and had no synergistic effect with estrogen, but its inhibition of anti-estrogen function may provide new insight into the mechanism of local estrogen action in endometriosis.

Meng X ，Liu J ，Wang H ，Chen P ，Wang D ... -  《-》

The role of miR-34c-5p/Notch in epithelial-mesenchymal transition (EMT) in endometriosis.

Endometriosis, a common benign gynecological disease, has the growth characteristics of malignant tumors, however, the pathogenesis of this disease remains unclear. It is well known that micro ribonucleic acids (miRNAs) are involved in epithelial-mesenchymal transition (EMT), associated with the development of endometriosis. This study investigated the role of a specific miRNA, miR-34c-5p, in endometriosis. High-throughput sequencing (HTS) showed that miR-34c-5p expression was reduced in ectopic endometrium (ecEM) in patients from Northeast Asia with ovarian endometriosis. A wound healing assay and a transwell invasion assay showed that miR-34c-5p inhibits the invasion and migration of Ishikawa and End1/E6E7 endocervical cells. Dual luciferase gene reporter assays revealed that miR-34c-5p specifically targets Notch1 3 'UTR, and Western blot analyses showed that miR-34c-5p promotes E-cadherin expression but inhibits Notch1, N-cadherin and vimentin expression in Ishikawa and End1/E6E7 cell lines. These results were reversed following knockdown of miR-34c-5p. Using quantitative real time reverse transcriptase polymerase chain reaction (qRT-PCR) and western blot analyses, there was a significant reduction in the expression of Notch1 in ecEM compared with eutopic endometrium (euEM). The results of this study indicate that miR-34c-5p inhibits the progression of EMT and cell invasion and migration by targeting the Notch signaling pathway, specifically, Notch1. The findings of this study provide unique insights into the development of EMT in endometriosis and novel, potential therapeutic targets.

Luo Y ，Wang D ，Chen S ，Yang Q ... -  《-》

miRNA-223 expression in patient-derived eutopic and ectopic endometrial stromal cells and its effect on epithelial-to-mesenchymal transition in endometriosis.

This study was designed to evaluate the expression of microRNA-223 (miRNA-223) in patient-derived eutopic and ectopic endometrial stromal cells (SCs). Given the fact that miRNA-223 was previously shown to be upregulated in these cells and that this upregulation has been linked to epithelial-to-mesenchymal transition (EMT) during endometriosis, this study aimed to further explore the expression of miRNA-223, its effect in endometriosis, and the mechanisms underlying its effects. Endometrial tissue was collected from 26 patients with endometriosis and 14 patients with hysteromyoma (control group). Primary endometrial SCs were isolated and cultured from several endometrial samples and miRNA-223 expression was evaluated using qRT-PCR. Cells were then transfected with a miRNA-223 overexpression lentiviral vector (sh-miR-223 cells) or an empty control (sh-NC cells) and then used to monitor the effects of miRNA-223 on the expression of several EMT-associated proteins, including N-cadherin, vimentin, and Slug, using western blot. Cellular migration, invasion, and proliferation were then evaluated using a wound healing, Transwell, and CCK-8 assay, respectively. Flow cytometry was used to detect apoptosis. There was a significant decrease in the expression of miRNA-223 in both eutopic and ectopic endometrial SCs (p < 0.05) whereas upregulation of miRNA-223 inhibited the expression of EMT-related molecules and reduced cell migration, invasion, and proliferation. High levels of miRNA-223 also promoted apoptosis. miRNA-223 expression decreased in endometrial SCs from endometriosis patients, which may facilitate the differential regulation of EMT during endometriosis. SWYX2020-211.

Xue Y ，Lin X ，Shi T ，Tian Y ... -  《-》

miR-96-5p regulated TGF-β/SMAD signaling pathway and suppressed endometrial cell viability and migration via targeting TGFBR1.

Chen S ，Luo Y ，Cui L ，Yang Q ... -  《-》

The estrogen-regulated lncRNA H19/miR-216a-5p axis alters stromal cell invasion and migration via ACTA2 in endometriosis.

Fibrotic tissue may contribute to the origin of some endometriosis-related symptoms, such as chronic pelvic pain and infertility. Alterations in the H19/miR-216a-5p/ACTA2 pathway may mediate the regulation of eutopic endometrial stromal cell (euESC) invasion and migration and may represent a potential mechanism underlying fibrous tissue formation or fibrosis in women with endometriosis. In this study, we aimed to determine the expression of H19 and ACTA2 in endometrial tissues of women with endometriosis. Two groups of 23 infertile women with endometriosis and 23 matched infertile women without endometriosis were investigated. Primary cultured cells of endometrial tissues were analyzed using RT-PCR and western blotting (WB) to determine expression of H19 and ACTA2. 5-Ethyl-2'-deoxyuridine, CCK8 and Transwell assays were used to study the functions of H19 and ACTA2. Human embryonic kidney 293 cells were used for luciferase assays to study miR-216a-5p binding sites with H19 and ACTA2. We found that H19 and ACTA2 levels were significantly higher in endometriosis euESCs than in control euESCs (P < 0.05) and were positively correlated in endometriosis euESCs. Luciferase assays indicated that H19 regulates ACTA2 expression via competition for inhibitory miR-216a-5p binding sites. Our results indicate that alterations in the estrogen/H19/miR-216a-5p/ACTA2 pathway regulated endometriosis euESC invasion and migration. Downregulation of H19 or ACTA2 inhibited endometriosis euESC invasion and migration; however, estrogen promoted endometriosis euESC invasion and migration via H19. The main limitation of our study was that experiments were conducted in vitro and further in vivo studies are required in the future. However, our study showed that primary cultured cells represented endometriosis cells more clearly than cell lines.

Xu Z ，Zhang L ，Yu Q ，Zhang Y ，Yan L ，Chen ZJ ... -  《-》