The expression of Nectin-4 on the surface of ovarian cancer cells alters their ability to adhere, migrate, aggregate, and proliferate

Abstract

The cell adhesion molecule Nectin-4 is overexpressed in epithelial cancers, including ovarian cancer. The objective of this study was to determine the biological significance of Nectin-4 in the adhesion, aggregation, migration, and proliferation of ovarian cancer cells. Nectin-4 and its binding partner Nectin-1 were detected in patients’ primary tumors, omental metastases, and ascites cells. The human cell lines NIH:OVCAR5 and CAOV3 were genetically modified to alter Nectin-4 expression. Cells that overexpressed Nectin-4 adhered to Nectin-1 in a concentration and time-dependent manner, and adhesion was inhibited by antibodies to Nectin-4 and Nectin-1, as well as synthetic Nectin peptides. In functional assays, CAOV3 cells with Nectin-4 knock-down were unable to form spheroids and migrated more slowly than CAOV3 parental cells expressing Nectin-4. NIH:OVCAR5 parental cells proliferated more rapidly, migrated faster, and formed larger spheroids than either the Nectin-4 knock-down or over-expressing cells. Parental cell lines expressed higher levels of epithelial markers and lower levels of mesenchymal markers compared to Nectin-4 knock-down cells, suggesting a role for Nectin-4 in epithelial-mesenchymal transition. Our results demonstrate that Nectin-4 promotes cell-cell adhesion, migration, and proliferation. Understanding the biology of Nectin-4 in ovarian cancer progression is critical to facilitate its development as a novel therapeutic target.

Ectodomain shedding of the cell adhesion molecule Nectin-4 in ovarian cancer is mediated by ADAM10 and ADAM17

“…AKT can be activated by treatment with LPA (58) and by ascites (59), and patients with AKT2 alterations have a poor prognosis (60). AKT promotes EMT (61), which corroborates our recent work in which Nectin-4 knockdown cells had increased expression of mesenchymal markers such as vimentin and decreased expression of epithelial markers such as E-cadherin (15).…”

“…Ovarian cancer cells exist both as free-floating single cells and as aggregated spheroids in ascites fluid, and our recent study showed that Nectin-4 is essential for the formation of compact spheroids (Fig. 7d) (15). We have previously published that spheroids adhere to mesothelial cells (Fig.…”

“…We have previously published that spheroids adhere to mesothelial cells (Fig. 7e) (4 -6), possibly through binding to Nectin-1 (15), and then invade the mesothelial cell layer (Fig. 7f), potentially through the cleavage of Nectin-4, thereby promoting migration and tissue invasion and eventually formation of a secondary tumor (Fig.…”

“…The results of this study and our previous work support the role of ADAM proteases and Nectin-4 cleavage in ovarian cancer progression. We have observed that cells expressing Nectin-4 migrate faster than Nectin-4 knockdown cells in a scratch wound assay (15). ADAM10 has been shown to be involved in the migration of cells, either in conjunction with ADAM17 through ectodomain cleavage of the adhesion molecule CD44 (23) or alone for leukocyte migration to the alveolar space (65).…”

“…We have previously shown that the human ovarian cancer cell line NIH:OVCAR5 expresses moderate levels of Nectin-4 (9,15). To facilitate detection and quantification of the extracellular sN4, NIH:OVCAR5 parental cells were transfected with full-length Nectin-4, and cells that overexpressed Nectin-4 (NIH:OVCAR5-N4-over) were selected using FACS.…”