J Breast Cancer.  2020 Aug;23(4):385-397. 10.4048/jbc.2020.23.e42.

Expression and Role of Epithelial Membrane Proteins in Tumorigenesis of Hormone Receptor-Positive Breast Cancer

• Cha YJ
• Koo JS

• KMID: 2511798
• DOI: http://doi.org/10.4048/jbc.2020.23.e42

Abstract

Purpose
Studies on the expression of epithelial membrane proteins (EMPs) in breast cancer have been rare and limited. In the present study, we aimed to evaluate the expression of EMP1, EMP2, and EMP3 in invasive ductal carcinoma (IDC) of the breast, and investigate their clinical implications.
Methods
In total, 418 IDC cases were collected, and specimens were used to construct a tissue microarray. Immunohistochemical staining of EMP1, EMP2, and EMP3 was performed and the results were analyzed in combination with the clinical data.
Results
EMP1 was expressed in > 90% of all IDC subtypes. A decreased expression of EMP2 and EMP3 was observed in triple-negative breast cancer. EMP3 expression was independently associated with human epidermal growth factor receptor 2 (HER2) positivity. HER2-negative cases exhibited a decreased EMP2 expression along with a higher histological grade and an increased proliferative index. No significant difference was found in the overall survival or disease-free survival based on the EMP expression. In HER2-negative breast cancer, EMP2 expression inversely correlated with the histological grade and proliferative index.
Conclusion
EMP2 may be involved in the early stage of tumor development in hormonepositive breast cancer.

Keyword

Breast neoplasms; EMP-2 protein; human; Immunohistochemistry; Pathology