Functional analysis of the histidine N-methyltransferase SETD3 in endometriosis

Study questionEndometriosis is characterized by invasive growth of endometrial tissue outside the uterus. The histidine N-methyltransferase SETD3 modulates actin function as a prerequisite for cell motlilty, contractility and invasive growth. Does SETD3 have an impact on invasive growth of endometriotic cells?

Materials, Methods This is an in-vitro laboratory study on the immortalized endometriotic cell line 12Z and primary endometriotic stroma cells.

Cells were subjected to siRNA-mediated knockdown of SETD3 or a negative control siRNA, the impact on cell motility, contractility, invasiveness, cytoskeletal morphology and gene expression were analyzed by rt-qPCR, Western blotting, ELISA, immunofluorescence, scratch wound assay, collagen contraction and Matrigel invasion.

Results SETD3 knockdown was confirmed by qPCR and Western blotting. Only moderate changes in cytoskeletal element gene expression were observed, whereas VEGF expression was downregulated by >40% in both experimental systems (p< 0.05,n>3). SETD3 depletion resulted in a delay in cell motility in scratch wound assays (p< 0.05,n>5), in a reduction in invasive growth of 12Z cells by 50% (p< 0.05,n>5) and in a reduced capability to contract collagen gels (p< 0.05,n>5). Immunofluorescence microscopy for actin revealed altered cytoskeletal morphology.

Summary SETD3 affects invasive growth, cell motility and contractility of endometriotic cells in vitro. The presented data suggest that methylation of beta-actin, as mediated by SETD3, contributes to the remodeling of the cytoskeleton that plays a key role in cell migration and invasion. A dysregulation of SETD3 could be related to invasive growth in endometriosis. This in-vitro study needs to be confirmed in more complex experimental models.

Publication History

Article published online:
07 October 2020