Ezrin Is Associated with Disease Progression in Ovarian Carcinoma.

Vered Horwitz,Dganit Stern,Claes G Tropé,Tali Tavor Re’Em,Ben Davidson,Reuven Reich,David Wai Chan

doi:10.1371/journal.pone.0162502

Abstract

ObjectiveEzrin and p130Cas are structural proteins with an important role in signaling pathways and have been shown to promote cancer dissemination. We previously reported on overexpression of both ezrin and p130Cas in breast carcinoma effusions compared to primary carcinomas. Since ovarian and breast carcinomas share the ability to disseminate by forming malignant effusions, we sought to study the role of these molecules in ovarian carcinoma (OC).MethodsOC cell lines were cultured in two different 3-dimensional conditions, on alginate scaffolds and as spheroids, which served as models for solid tumor and malignant effusions, respectively. shRNA was used to reduce protein expression in the cells. The malignant potential was evaluated by chemo-invasion assay, branching capacity on Matrigel and rate of proliferation. Subsequently, clinical specimens of high-grade serous carcinoma effusions, ovarian tumors and solid metastases were analyzed for ezrin and p130Cas expression.ResultsHigher ezrin expression was found in cells composing the spheroids compared to their counterparts cultured on alginate scaffold and in clinical samples of malignant effusions compared to solid tumors. In addition, reduced Ezrin expression impaired the invasion ability and the branching capacity of OC cells to a greater extent than reduced p130Cas expression. However, ezrin and p130Cas expression in effusions was unrelated to clinical outcome.ConclusionsThe 3-dimensional cell cultures were found to mimic the different tumor sites and be applicable as a model. The in vitro results concur with the clinical specimen analysis, suggesting that in OC, the role of ezrin in disease progression is more pronounced than that of p130Cas.

Highlights

Ezrin and p130Cas are two different cytosolic structural proteins that play an important role in signaling pathways affecting the cytoskeleton and regulating cell motility and proliferation [1,2].Ezrin is part of the ERM family of proteins that function as linkers between the plasma membrane and the actin cytoskeleton
Higher ezrin expression was found in cells composing the spheroids compared to their counterparts cultured on alginate scaffold and in clinical samples of malignant effusions compared to solid tumors
ovarian carcinoma (OC) cells cultured as spheroids and OC effusions have higher ezrin expression Analysis of ezrin protein expression in ES2 and OVCAR3 cells cultured on alginate scaffolds and as spheroids showed higher expression in the latter, though not significantly (Fig 1A)

Summary

Introduction

Ezrin and p130Cas are two different cytosolic structural proteins that play an important role in signaling pathways affecting the cytoskeleton and regulating cell motility and proliferation [1,2]. Ezrin is part of the ERM (ezrin, radixin, moesin) family of proteins that function as linkers between the plasma membrane and the actin cytoskeleton. As such, they are placed at the center of a regulatory network of many cellular processes, in both physiological and pathological conditions [2,3]. The active ezrin (p-ezrin) translocate to the cell membrane and interacts with transmembrane proteins, as well as the cytoskeleton, regulating cell morphology and motility and transducing growth signals [2,4]. Ezrin has been shown to promote cancer dissemination by several mechanisms including changes in signaling, increased cell motility and the ability to survive anoikis, invade and proliferate in 3-dimensional environment [2,7,10,13]

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Results

Conclusion