ECM1 promotes migration and invasion in endometriosis

Extracellular matrix protein 1 (ECM1) is a glycoprotein that may be a key player in tumorigenesis and tumor progression. However, knowledge regarding the role of ECM1 in endometriosis (EM) is still lacking. Microarray analyses were performed to compare the mRNA expression patterns between paired EU tissues and ectopic endometrial (EC) tissues (n = 4) from EM patients. ECM1 expression was significantly increased in the eutopic endometrial (EU) tissues than paired EC tissues of endometriotic patients and normal endometrial (NE) tissues of controls without EM. Blocking ECM1 with siRNA attenuated the migration and invasion of hEM15A cells and modified the distribution of the F-actin cytoskeleton. We conducted microarray analyses and bioinformatics analyses to investigate the differentially expressed genes (DEGs) and related pathways regulated by ECM1. A total of 161 DEGs between the siECM1 and the negative control (siNC) treatments were identified, consisting of 79 downregulated genes and 82 upregulated genes. Enriched DEGs were associated with 9 gene ontology (GO) terms. Moreover, a protein-protein interaction (PPI) network was constructed for the hub genes and modules. Radixin (RDX) was the second most downregulated gene in the siECM1 group compared with the siNC group. ECM1 knockdown significantly decreased the expression of RDX, RhoC, ROCK1, N-cadherin and beta-catenin but not ROCK2. ECM1 showed high tissue-specific expression in EU tissues from EM patients, and may contribute to the migration, invasion and reorganization of the F-actin cytoskeleton in eutopic endometrial stromal cells via the RhoC/ROCK1 signaling pathway in EM.