Email updates

Keep up to date with the latest news and content from WJSO and BioMed Central.

Open Access Highly Accessed Research

Significance of EpCAM and TROP2 expression in non-small cell lung cancer

Min Gyoung Pak1, Dong Hoon Shin13*, Chang Hun Lee13* and Min Ki Lee2

Author Affiliations

1 Department of Pathology, School of Medicine, Pusan National University, Beomeo-ri, Mulgeum-eup, Yangsan 626-770, South Korea

2 Department of Internal Medicine, Pusan National University, Yangsan 626-770, South Korea

3 Medical Research Institute, Pusan National University, Yangsan 626-770, South Korea

For all author emails, please log on.

World Journal of Surgical Oncology 2012, 10:53  doi:10.1186/1477-7819-10-53

Published: 6 April 2012

Abstract

Background

The tumor-associated calcium signal transducer (TACSTD) genes, originally designated epithelial cell adhesion molecule (EpCAM) and TROP2, represent true oncogenes. Little is known about EpCAM and TROP2 gene expression in non-small cell lung carcinoma (NSCLC). This study evaluated EpCAM and TROP2 protein expression and clinicopathologic significance in cases of NSCLC.

Methods

Tissue microarray blocks acquired from 164 cases of NSCLC, including 100 cases of adenocarcinoma (AdC) and 64 of squamous cell carcinoma (SCC), were examined by immunohistochemical staining for EpCAM, and TROP2. The results were correlated with clinicopathologic data.

Results

EpCAM and TROP2 were significantly overexpressed in SCC than in AdC (P < 0.01). In AdC, EpCAM overexpression was closely related to sex, histologic grade, pathologic T stage, pathologic N stage, and TNM stage, and TROP2 overexpression was only related to histologic grade (P < 0.05, respectively). In SCC, correlations were evident between EpCAM overexpression and TNM stage (P = 0.01), and between TROP2 overexpression and pathologic T stage (P = 0.02). EpCAM overexpression showed no significance with overall survival in AdC and SCC patients. However, TROP2 overexpression in AdC had a positive influence on overall survival (P = 0.02) and disease-free survival (P = 0.03). In particular, AdC patients with stage II or III showed better overall survival (P = 0.05) and disease-free survival (P = 0.04).

Conclusions

While EpCAM and TROP2 show weak and non-complete membranous staining in normal bronchial epithelium and pneumocyte, their complete membranous expression in carcinoma suggests their role in carcinogenesis. EpCAM and TROP2 were more frequently overexpressed in SCC. EpCAM overexpression had no prognostic value in this study, but TROP2 overexpression showed better survival in AdC patients and might be a better prognostic marker in advanced stage AdC.

Keywords:
Non-small cell lung cancer; prognosis; EpCAM; TROP2