Long noncoding RNA ADAMTS9-AS1 represses ferroptosis of endometrial stromal cells by regulating the miR-6516-5p/GPX4 axis in endometriosis.

Endometriosis (EMs) is one of the most frequent diseases of reproductive-age women and is characterized by the growth of endometrial tissues beyond the uterus. The enhanced proliferative and migratory potential of endometrial stromal cells (ESCs) plays an important role in the progression of EMs. Mounting studies have demonstrated that long noncoding RNAs (lncRNAs) exert an important role in regulating the development and progression of EMs. Given the aberrant expression of lncRNA ADAMTS9-AS1 in ectopic endometrium (ecEM), we investigated the biological effect of ADAMTS9-AS1 on ESC proliferation and migration and explored the underlying mechanism. The current data showed that ADAMTS9-AS1 expression was significantly upregulated in ecEM compared with eutopic endometrium (euEM) in patients with EMs and in a murine model of EMs. Functionally, ADAMTS9-AS1 knockdown in ectopic ESCs (EESCs) decreased cell viability and migration, whereas ADAMTS9-AS1 overexpression in normal ESCs (NESCs) enhanced cell viability and migration. More importantly, the effect of ADAMTS9-AS1 inhibition on decreasing ESC viability was significantly blocked by ferrostatin-1 (Fer-1, a ferroptosis inhibitor), and ADAMTS9-AS1 overexpression repressed erastin (a ferroptosis activator)-induced cell death. Furthermore, the regulatory role of ADAMTS9-AS1 in ferroptosis was defined and evidenced by increased reactive oxygen species (ROS) levels and malonyl dialdehyde (MDA) content and decreased expression of glutathione peroxidase 4 (GPX4) after ADAMTS9-AS1 inhibition. Mechanistically, ADAMTS9-AS1 functioned as a competing endogenous RNA (ceRNA) by sponging miR-6516-5p to derepress the expression of GPX4, the critical repressor of ferroptosis. Taken together, these results demonstrate that upregulated ADAMTS9-AS1 accelerates ESC proliferation and migration by regulating miR-6516-5p/GPX4-dependent ferroptosis and may be a potential target for the treatment of EMs.

LncRNA ADAMTS9-AS1, as prognostic marker, promotes cell proliferation and EMT in colorectal cancer.

The long non-coding RNA antisense 1 ADAMTS9-AS1 has been reported to predict the survival in several tumors, including bladder cancer and breast cancer. However, the clinical significance and biological behaviors of ADAMTS9-AS1 in colorectal cancer (CRC) have not been reported yet. In this study, the expression of ADAMTS9-AS1 was measured in CRC tissues and cell lines using quantitative real-time PCR analysis. The clinical significance of ADAMTS9-AS1 was evaluated with Chi-squared test, Kaplan-Meier method and Cox regression analysis in CRC patients. CCK8 assay, colony formation assay, flow cytometry and transwell assay were used to explore the biological function of ADAMTS9-AS1 knockdown in CRC cell lines (SW1116 and HT29). We further explore the role of ADAMTS9-AS1 in vivo though xenograft tumor assay. Our data showed that ADAMTS9-AS1 expression level was significantly up-regulated in CRC tissues and cell lines compared with corresponding controls. High ADAMTS9-AS1 level was associated with TNM stage, lymph node invasion and worse survival prognosis. Depletion of ADAMTS9-AS1 significantly suppressed cell proliferation, G1/S transition, migration and invasion, as well as suppressed CDK4/Cyclin D1 and epithelial-mesenchymal transition (EMT). To sum up, these findings illustrated that ADAMTS9-AS1 might be a promising therapeutic target and prognostic factor for CRC.

Upregulation of TNF-α and IL-6 induces preterm premature rupture of membranes by activation of ADAMTS-9 in embryonic membrane cells.

AIM: To investigate the role of thrombospondin motifs 9 (ADAMTS9) in preterm premature rupture of membranes (pPROM). MATERIALS AND METHODS: ADAMTS9 levels were measured in amnion cells from 24 patients of different groups (preterm vs. full-term birth, with vs. without PROM). ADAMTS9 was suppressed in human amnioblasts to investigate its effects on embryonic membrane cells and inflammation-induced cell damage. Pregnant mouse models were used to assess whether inflammation regulates ADAMTS9 by upregulating TNF-α and IL-6, contributing to the preterm birth occurrence. KEY FINDINGS: We found that ADAMTS9 protein and gene expression levels significantly differed among various groups (pPROM > full-term PROM > preterm non-PROM > full-term non-PROM). After ADAMTS9 suppression in human amnioblast WISH cells, TNF-α- and IL-6-induced apoptosis was decreased. In addition, TNF-α, IL-6, and ADAMTS9 protein and gene expression levels were increased in the embryos of mice treated with LPS compared with controls. In agreement, the rate of preterm birth was higher in the LPS group compared with controls. SIGNIFICANCE: Taken together, these in vitro and in vivo findings suggest that TNF-α and IL-6 secreted by macrophages during inflammation regulate ADAMTS9 and induce pPROM.

Genetic and biochemical evidence that gastrulation defects in Pofut2 mutants result from defects in ADAMTS9 secretion.

Protein O-fucosyltransferase 2 (POFUT2) adds O-linked fucose to Thrombospondin Type 1 Repeats (TSR) in 49 potential target proteins. Nearly half the POFUT2 targets belong to the A Disintegrin and Metalloprotease with ThromboSpondin type-1 motifs (ADAMTS) or ADAMTS-like family of proteins. Both the mouse Pofut2 RST434 gene trap allele and the Adamts9 knockout were reported to result in early embryonic lethality, suggesting that defects in Pofut2 mutant embryos could result from loss of O-fucosylation on ADAMTS9. To address this question, we compared the Pofut2 and Adamts9 knockout phenotypes and used Cre-mediated deletion of Pofut2 and Adamts9 to dissect the tissue-specific role of O-fucosylated ADAMTS9 during gastrulation. Disruption of Pofut2 using the knockout (LoxP) or gene trap (RST434) allele, as well as deletion of Adamts9, resulted in disorganized epithelia (epiblast, extraembryonic ectoderm, and visceral endoderm) and blocked mesoderm formation during gastrulation. The similarity between Pofut2 and Adamts9 mutants suggested that disruption of ADAMTS9 function could be responsible for the gastrulation defects observed in Pofut2 mutants. Consistent with this prediction, CRISPR/Cas9 knockout of POFUT2 in HEK293T cells blocked secretion of ADAMTS9. We determined that Adamts9 was dynamically expressed during mouse gastrulation by trophoblast giant cells, parietal endoderm, the most proximal visceral endoderm adjacent to the ectoplacental cone, extraembryonic mesoderm, and anterior primitive streak. Conditional deletion of either Pofut2 or Adamts9 in the epiblast rescues the gastrulation defects, and identified a new role for O-fucosylated ADAMTS9 during morphogenesis of the amnion and axial mesendoderm. Combined, these results suggested that loss of ADAMTS9 function in the extra embryonic tissue is responsible for gastrulation defects in the Pofut2 knockout. We hypothesize that loss of ADAMTS9 function in the most proximal visceral endoderm leads to slippage of the visceral endoderm and altered characteristics of the extraembryonic ectoderm. Consequently, loss of input from the extraembryonic ectoderm and/or compression of the epiblast by Reichert's membrane blocks gastrulation. In the future, the Pofut2 and Adamts9 knockouts will be valuable tools for understanding how local changes in the properties of the extracellular matrix influence the organization of tissues during mammalian development.