Overexpression of GRP78 Is Associated With Malignant Transformation in Epithelial Ovarian Tumors

Abstract

Glucose-regulated protein 78 (GRP78) is one of the best-characterized endoplasmic reticulum chaperone proteins. The aim of this study was to explore the potential implications of GRP78 in the development of epithelial ovarian carcinomas (EOCs) and the possible clinical usefulness of GRP78 expression as a prognostic biomarker for EOCs. A total of 133 women were enrolled. This pilot study consisted of 96 cases of EOCs and 37 cases of benign ovarian tumors as controls. The expression of GRP78 protein was studied using tissue microarray technology and immunohistochemistry. Of the 96 invasive carcinomas analyzed, 25 cases (26.0%) showed moderate GRP78 expression and 65 cases (67.7%) showed strong GRP78 expression. Conversely, 17 (45.9%) of the 37 patients with benign ovarian tumors showed no or weak GRP78 staining. Our results demonstrated that GRP78 expression was significantly higher in EOCs than in benign ovarian tumors (P<0.001). However, no statistically significant association was found between GRP78 expression and survival. The present study suggests that GRP78 plays a significant role in malignant transformation of epithelial ovarian tumors and may represent an important biomarker for EOCs.