EMP2 Assay Portfolio Service

Epithelial Membrane Protein 2 (EMP2)

EMP2 is a member of the growth arrest-specific gene 3/peripheral myelin protein-22 (GAS3/PMP22) group of tetraspan proteins. Structurally, EMP2 is a hydrophobic protein with four predicted transmembrane domains, two extracellular domains, and small intracellular regions. EMP2 is approximately 160 amino acids translating into an 18 kDa polypeptide core with three N-linked glycosylation sites on its first extracellular loop. EMP2 is typically located in the cytoplasm or cellular membrane and plays diverse roles in tumor carcinogenesis, proliferation, and metastasis. Moreover, EMP2 is a novel oncogene upregulated in a number of gynecological tumors. However, the roles of EMPs (EPM1, EPM2, and EPM3) in invasion and metastasis in diverse cancers are controversial.

Fig.1 Structure of EMPs, and signal transduction molecules that are affected by EMPs. (Ahmat Amin, 2019)

Functions of EMP2

EMP2 has been associated with various functions including endocytosis, cell signaling, cell proliferation, cell migration, cell adhesion, cell death, cholesterol homeostasis, urinary albumin excretion, and embryo implantation.

• Under physiological conditions, EMP2 may function as a trafficking molecule for a variety of proteins and glycolipids to efficiently transfer from a post-Golgi endosomal compartment to the plasma membrane.
• EMP2 appears to regulate the expression of select integrins, glycosylphosphatidylinositol-anchored proteins, and class 1 major histocompatibility complex (MHC I) proteins where it helps to traffic these proteins into lipid raft domains. In this way, EMP2 appears to help stabilize select integrins, modulating adhesion onto various extracellular matrices.
• EMP2 physically associates with and regulates the activity of integrin-focal adhesion kinase (FAK) signaling complexes, with the consequence that high levels of EMP2 increase tumor cell invasion.
• EMP2 regulates blood vessel endothelial cell migration and angiogenesis by regulating vascular endothelial growth factor (VEGF) protein expression through protein tyrosine kinase 2 (PTK2) activation and regulates cell migration and cell contraction through PTK2 and SRC activation.
• Mutations in EMP2 have been linked to childhood-onset nephrotic syndrome.

Expression of EMP2

• In normal tissues

EMP2 is most commonly expressed in the lung, skin, and esophagus, In addition, the expression of EMP2 was found in multiple structures of the eye, such as the cornea, ciliary body, and the epithelium of the retina. The transcript level of EMP2 is elevated in the fetal lung and kidney, but not in the adult thymus and peripheral leukocytes.

• In cancers

Overexpression of EMP2 is associated with tumor progression as well as poor patient survival. Its expression is up-regulated in ovarian, breast, and endometrial malignancies. Within these tumors, EMP2 is a prognostic indicator as its expression correlates with poor survival and/or advanced disease.

EMP2 and Tumors

Analogous to other tetraspan proteins, the history of EMP2 in cancer has been variable.

• Pro-tumor properties.

EMP2 functions as an oncoprotein. EMP2 mRNA is upregulated in a number of cancers including breast, ovarian, endometrial, and primary CNS malignancies. The level of EMP2 protein is positively associated with cancer progression, which is supported by findings that EMP2 is expressed in 67% of lymph node metastases and is linked with lymphovascular invasion. EMP2 promotes more aggressive disease.

• Anti-tumor properties.

EMP2 was also reported to have an apoptotic effect in a B-cell lymphoma cell line, nasopharyngeal and urinary tract urothelial carcinoma. EMP2 protein is expressed at low levels or is undetectable in nasopharynx cancer. And EMP2 possesses anti-tumor properties by suppressing the growth of nasopharyngeal carcinoma cells. EMP2 protein expression inversely correlates with the histologic grades of uroepithelial cancer cells, and overexpression of EMP2 impairs cancer cell proliferation and inhibits tumor development.

EMP2 Assay Portfolio Service for Research

EMP2 is a tetraspan protein that is upregulated in many gynecological cancers. EMP2 can be used as a prognostic marker in some gynecological tumors. Creative Biolabs provides a full set of EMP2 assay portfolio services for research, which including but not limited to:

• Angiogenesis assays (tube formation assay, sprouting assay, and additional angiogenesis assays)
• Cell proliferation assay
• Cell migration assay (transwell assay)
• Wound healing assay
• Apoptosis assay
• In vitro tumor sensitivity assay (soft agar colony formation）
• ELISA
• Immunoprecipitations
• Immunohistochemistry

Creative Biolabs provides a complete portfolio of tumor marker assay development and validation services that can be used from preclinical development through proof of concept. Our scientific team now provides professional and tailored solutions for our worldwide clients. Please feel free to contact us.

Reference

• Ahmat Amin, M.K.; et al. The pivotal roles of the epithelial membrane protein family in cancer invasiveness and metastasis. Cancers (Basel). 2019, 11(11): 1620.

For Research Use Only | Not For Clinical Use

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