Decreased expression of Ep-CAM protein is significantly associated with the progression and prognosis of oral squamous cell carcinomas in Taiwan

Immunolocalization of epithelial cell adhesion molecule and matrix metalloproteinase-9 in oral epithelial dysplasia and oral squamous cell carcinoma

INTRODUCTION

Cancers are complex tissues composed of multiple distinct cell types that participate in heterotypic interactions with one another. Physiologically cell-to-cell contacts formed by dense populations of normal cells operate to suppress further cell proliferation.

OBJECTIVES

The objective of the study is to evaluate and compare the immunoexpression of matrix metalloproteinase-9 (MMP-9) and epithelial cell adhesion molecule (EpCAM) in oral epithelial dysplasia (OED) and oral squamous cell carcinoma (OSCC) and to hypothesize their role in the progression in varying grades of these lesions.

MATERIALS AND METHODS

A total of 60 samples comprising of 30 cases each of OED and OSCC. Three micrometers thin sections were taken and subjected for hematoxylin and eosin stain and immunohistochemical procedure. The sections were incubated with monoclonal anti-EpCAM anti-MMP-9 antibody. The data were analyzed using SPSS software version 19.

RESULTS

The results of the study show EpCAM immunoexpression decreased in OSCC when compared to OED. MMP-9 immunoexpression increased in OSCC when compared to OED (statistically significant, P ≤ 0.05).

CONCLUSION

Correlation between EpCAM and MMP-9 may help to unravel the signaling cascades involved in the carcinomatous changes, tumor cell invasion, and progression of OSCCs.

Epithelial Cell Adhesion Molecule in Primary Sjögren's Syndrome Patients: Characterization and Evaluation of a Potential Biomarker

Objective

To determine the subcellular localization of epithelial cell adhesion molecule (EpCAM) in labial salivary gland (LSG) and evaluate the diagnostic use of the extracellular domain of EpCAM (EpEX) and intracellular domain (EpICD) for primary Sjögren's syndrome (pSS).

Methods

Immunohistochemical (IHC) analysis was conducted using EpEX and EpICD domain-specific antibodies on labial salivary gland biopsy (LSGB) from participants. Chi-square or Fisher's exact analysis, Mann-Whitney U-test, and Kruskal-Wallis test compared differences among groups. Independent risk factors of pSS were determined by multiple logistic regression analysis. Receiver-operator characteristic curves (ROC) were carried out to estimate the diagnostic value.

Results

Compared to non-SS controls, loss of membranous EpEX and EpICD expression was observed in LSGB of pSS patients, which occurred in parallel with increased accumulation of cytoplastic and nuclear EpICD. The subcellular EpEX/EpICD expressions were associated with various features of pSS patients, especially histopathological grade of LSGB. Furthermore, high IHC scores of membranous EpEX were independent risk factors for pSS, even for the pSS patients at early stage. The IHC scores of subcellular EpEX/EpICD were of great diagnostic value for pSS with high sensitivity (70-80%) and specificity (85-95%).

Conclusion

This study first found the aberrant expression pattern of EpCAM in LSG of pSS patients. The IHC scores of subcellular EpEX/EpICD were demonstrated to have the potential to act as diagnostic biomarkers for pSS.

The expression of EpCAM in extramammary Paget's disease

Extramammary Paget's disease (EMPD) is a rare skin malignant tumor. The prognosis of EMPD with distant metastasis is poor, however an effective therapy has not yet established. Recently, EpCAM (epithelial cell adhesion molecule, CD326) has attracted attention as both prognostic marker and therapeutic target in several cancers. Besides, EpCAM is an important surface marker of circulating tumor cell (CTC) in the collection of CTC. Thus, the purpose of our study was to examine the expression levels of EpCAM and evaluate the correlation between its intensity of EpCAM and the clinical characteristics of EMPD. The expression of EpCAM in EMPD was examined using immunohistochemistry. Skin samples were obtained from 32 patients with EMPD. We found that almost all EMPD tissues (90.6%, 29/32) were positive for EpCAM. Furthermore, the staining intensity of EpCAM protein negatively correlated with the presence of distant metastasis. Overexpression of EpCAM in EMPD cells suggests that EpCAM may be a novel therapeutic target and the research of CTC may be newly developed in EMPD. Based on these findings, EpCAM may be a meaningful molecule in EMPD.

Functions of EpCAM in physiological processes and diseases (Review)

EpCAM (epithelial cell adhesion molecule) is a type I transmembrane glycoprotein, which was originally identified as a tumor-associated antigen due to its high expression level in rapidly growing epithelial tumors. Germ line mutations of the human EpCAM gene have been indicated as the cause of congenital tufting enteropathy. Previous studies based on cell models have revealed that EpCAM contributes to various biological processes including cell adhesion, signaling, migration and proliferation. Due to the previous lack of genetic animal models, the in vivo functions of EpCAM remain largely unknown. However, EpCAM genetic animal models have recently been generated, and are useful for understanding the functions of EpCAM. The authors here briefly review the functions and mechanisms of EpCAM in physiological processes and different diseases.

Epithelial cell adhesion molecule overexpression regulates epithelial-mesenchymal transition, stemness and metastasis of nasopharyngeal carcinoma cells via the PTEN/AKT/mTOR pathway

Epithelial cell adhesion molecule (EpCAM) is known to be highly expressed in a variety of epithelial carcinomas, and it is involved in cell adhesion and proliferation. However, its expression profile and biological function in nasopharyngeal carcinoma (NPC) remains unclear. In this study, higher expression of EpCAM was found in NPC samples compared with non-cancer nasopharyngeal mucosa by qRT-PCR. Additionally, immunohistochemistry (IHC) analysis of NPC specimens from 64 cases showed that high EpCAM expression was associated with metastasis and shorter survival. Multivariate survival analysis identified high EpCAM expression as an independent prognostic factor. Ectopic EpCAM expression in NPC cells promoted epithelial-mesenchymal transition (EMT), induced a cancer stem cell (CSC)-like phenotype, and enhanced metastasis in vitro and in vivo without an effect on cell proliferation. Notably, EpCAM overexpression reduced PTEN expression and increased the level of AKT, mTOR, p70S6K and 4EBP1 phosphorylation. Correspondingly, an AKT inhibitor and rapamycin blocked the effect of EpCAM on NPC cell invasion and stem-like phenotypes, and siRNA targeting PTEN rescued the oncogenic activities in EpCAM knockdown NPC cells. Our data demonstrate that EpCAM regulates EMT, stemness and metastasis of NPC cells via the PTEN/AKT/mTOR pathway.

Differential expression of epithelial cell adhesion molecule in salivary gland neoplasms

Epithelial cell adhesion molecule (EpCAM) is the epithelial-specific molecule expressed on various epithelial cell types. The function of EpCAM involves cellular adhesion, proliferation, and signaling in both normal tissues and cancers. The purposes of this study were to investigate the EpCAM expression in salivary gland neoplasms and examine its relationship with pathologic characteristics. Forty-two cases of salivary gland neoplasms, including 20 mucoepidermoid carcinomas (MECs), 11 adenoid cystic carcinomas (ACCs), 9 pleomorphic adenomas (PAs), and 2 polymorphous low-grade adenocarcinomas (PLGAs) were enrolled. Epithelial cell adhesion molecule expression was analyzed immunohistochemically using MOC-31 and BerEP4 antibodies. Results showed that the majority of MECs and all PLGAs showed EpCAM expression in more than 50% of neoplastic cells, whereas most PAs and ACCs did not express this protein. In MECs, most EpCAM-positive neoplastic cells were clear cells, glandular epithelial cells, and intermediate cells, whereas squamous cells and mucous cells were largely negative. The expression was limited to ductal epithelium in EpCAM-positive PAs and ACCs. The decreased EpCAM expression in MECs was significantly associated with microscopically diminished cystic components, the presence of small nest invasion at invasive front, cellular anaplasia, vascular invasion, and high pathologic grade. These data suggested that EpCAM showed different expression pattern among salivary gland neoplasms and in different grades of MECs.

Predictive value of E-cadherin and Ep-CAM in cervical lymph node metastasis of supraglottic larynx carcinoma

OBJECTIVE

To evaluate the value of E-cadherin and epithelial cell adhesion molecule (Ep-CAM) expression in laryngeal biopsy materials for predicting cervical lymph node metastasis in patients with supraglottic laryngeal carcinoma.

METHODS

All patients participating in the study were selected from among the surgically treated patients at the department of Otolaryngology, Head and Neck Surgery, Erciyes University School of Medicine between 1991 and 2005. The study consisted of thirty patients who had pathologically metastatic lymph nodes (pN+ group) and 30 age-, sex-, T value- and differentiation matched patients without pathologically metastatic lymph nodes (pN0 group). Immunohistochemical studies were performed with E-cadherin and Ep-CAM antibodies on representative tumor sections collected from paraffin sections of laryngeal biopsy materials. The expression of E-cadherin and Ep-CAM was compared between the pN0 and pN+ groups. The association between immunostaining of E-cadherin and Ep-CAM was also evaluated.

RESULTS

There was no significant difference between the two groups in terms of E-cadherin and Ep-CAM expression. There was also a very poor agreement between the expression of E-cadherin and Ep-CAM.

CONCLUSION

Multi-institutional and multidisciplinary immunohistochemical studies conducted with standardized methodology and also with more patient participation may help to obtain more specific results.

Can immunohistochemistry serve as an alternative to subjective histopathological diagnosis of oral epithelial dysplasia?

Many attempts have been made to identify objective molecular biomarkers to diagnose and prognosticate oral epithelial dysplasia (OED) because histopathological interpretation is subjective and lacks sensitivity. The majority of these efforts describe changes in gene expression at protein level in OED as determined by immunohistochemistry (IHC). However, the literature on these putative markers of oral cancer progression is vast and varied. The main purpose of this article is to review current knowledge on biomarkers of protein expression for OED by IHC approaches. We further discuss these findings in terms of the proposed essential hallmarks of cancer cells to better understand their role in oral oncogenesis.

Role of the EpCAM (CD326) in prostate cancer metastasis and progression

Despite significant advances in surgery, radiotherapy and chemotherapy to treat prostate cancer (CaP), many patients die of secondary disease (metastases). Current therapeutic approaches are limited, and there is no cure for metastatic castration-resistant prostate cancer (CRPC). Epithelial cell adhesion molecule (EpCAM, also known as CD326) is a transmembrane glycoprotein that is highly expressed in rapidly proliferating carcinomas and plays an important role in the prevention of cell-cell adhesion, cell signalling, migration, proliferation and differentiation. Stably and highly expressed EpCAM has been found in primary CaP tissues, effusions and CaP metastases, making it an ideal candidate of tumour-associated antigen to detect metastasis of CaP cells in the circulation as well as a promising therapeutic target to control metastatic CRPC disease. In this review, we discuss the implications of the newly identified roles of EpCAM in terms of its diagnostic and metastatic relevance to CaP. We also summarize EpCAM expression in human CaP and EpCAM-mediated signalling pathways in cancer metastasis. Finally, emerging and innovative approaches to the management of the disease and expanding potential therapeutic applications of EpCAM for targeted strategies in future CaP therapy will be explored.

Epithelial cell adhesion molecule expression in pituitary adenomas: an immunohistochemical study

An important amount of data correlating the expression of epithelial cell adhesion molecule (Ep-CAM) with cellular proliferation and de-differentiation could directly contribute to carcinogenesis. The aim of this study is to evaluate prognosis relevance of Ep-CAM expression in a group of pituitary adenomas. Epithelial cell adhesion molecule, proliferating cell nuclear antigen, and microvascular density labeling indices in pituitary adenomas were determined by immunohistochemistry on tissue samples obtained from each adenoma after surgery. We evaluated 45 adenomas. Sixty-two percent were nonsecretor adenomas and 37.8% were secretor tumors. Immunohistochemistry was scored for immunoexpression of Ep-CAM (cytoplasmic, membrane, and mixed pattern). Proliferating cell nuclear antigen and vascular density (CD34) labeling indices were assessed. Statistical significance was observed between Ep-CAM cytoplasmic immunoreactions (P = .000) and higher proliferating cell nuclear antigen (P = .001) in secretor adenomas compared with nonsecretor tumors. Vascular density labeling indices did not show statistical significance. Therefore, Ep-CAM could be evaluated to distinguish secretor and nonsecretor pituitary adenomas. These suggest that the markers could predict the growth potential of individual pituitary adenomas.

Gene Expression Signatures of Lymph Node Metastasis in Oral Cancer: Molecular Characteristics and Clinical Significances

Even though lymph node metastasis accounts for the vast majority of cancer death in patients with oral cancer (OC), the molecular mechanisms of lymph node metastasis remain elusive. Genome-wide microarray analyses and functional studies in vitro and in vivo, along with detailed clinical observations, have identified a number of molecules that may contribute to lymph node metastasis. These include lymphangionenic cytokines, cell adhesion molecules, basement membrane-interacting molecules, matrix enzymes and relevant downstream signaling pathways. However, defined gene signatures from different studies are highly variable, which hinders their translation to clinically relevant applications. To date, none of the identified signatures or molecular biomarkers has been successfully implemented as a diagnostic or prognostic tool applicable to routine clinical practice. In this review, we will first introduce the significance of lymph node metastasis in OC, and clinical/experimental evidences that support the underlying molecular mechanisms. We will then provide a comprehensive review and integrative analysis of the existing gene expression studies that aim to identify the metastasis-related signatures in OC. Finally, the remaining challenges will be discussed and our insights on future directions will be provided.

EpCAM in carcinogenesis: the good, the bad or the ugly

The epithelial cell adhesion molecule (EpCAM) is a membrane glycoprotein that is highly expressed on most carcinomas and therefore of potential use as a diagnostic and prognostic marker for a variety of carcinomas. Interestingly, EpCAM is explored as target in antibody-based therapies. Recently, EpCAM has been identified as an additional marker of cancer-initiating cells. In this review, we describe the controversial biological role of EpCAM with the focus on carcinogenesis: as an adhesion molecule, EpCAM mediates homophilic adhesion interactions, which in turn might prevent metastasis. On the other hand, EpCAM abrogates E-cadherin mediated cell-cell adhesion thereby promoting metastasis. Also, upon cleavage of EpCAM, the intracellular domain functions as a part of a transcriptional complex inducing c-myc and cyclin A and E. In line with these seemingly controversial roles, EpCAM overexpression has been associated with both decreased and increased survival of patients. Similarly, either induction or downregulation of EpCAM expression lowers the oncogenic potential depending on the cell type. As epigenetic dysregulation underlies aberrant EpCAM expression, we propose epigenetic editing as a novel approach to investigate the biological role of EpCAM, expanding the options for EpCAM as a therapeutic target in cancer.