Stomatin-like Protein-2 Promotes Aggregation, Colonization and Migration of Endometriotic Cells

Abstract

Endometriosis is a chronic gynecological disease in women of childbearing age, which leads to infertility with risk of endometrial and ovarian cancer. The pathogenesis of endometriosis is poorly understood, and cure/treatment for it is not available, except for symptomatic treatment. The recurrence rate of endometriosis is high. SLP-2 is an inner mitochondrial membrane protein whose participation has been explained in cases of endometrial stromal cell growth, differentiation and migration, but its role in endometriosis is yet to be understood. Previous studies have found altered expression of stomatin-like protein 2 (SLP-2) in the serum of endometriotic patients. Therefore, we have studied the possible role of SLP-2 in the development of endometriosis. We found the ubiquitous and high expression of SLP-2 in the endometriotic tissue of both human endometriosis patients and rat endometriosis model. SLP-2 is seen in the glandular epithelial cells and stromal cells in the eutopic/normal or non-endometriosis group endometrium from human subjects. Finding high expression levels of SLP-2 in endometriotic tissue and ovarian cystic cells derived from endometriosis patients, we explored the possible role of SLP-2 in the cell aggregation, colonization, migration, and invasion in the human endometriotic cells associated with the progression of the endometriosis. Transient silencing of SLP-2 by its siRNA hinders endometriotic cells, aggregation, migration, and invasion into the extracellular matrix, which confirms SLP-2 involvement in endometriotic disease onset and progression. This study unravels the ubiquitous expression of SLP-2 in the human ectopic endometrial tissue and its role in the endometriotic cell migration, colonization, aggregation, and invasion leading to endometriosis progression.

Keywords: Cell aggregation; Cell colonization; Cell migration; Endometriosis; Human endometriotic tissue and cells; SD rat model; Spheroid invasion; Stomatin-like protein-2 (SLP-2).