Carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5) (CEACAM5)

Carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5), commonly known as CEA, is a cell surface glycoprotein and a member of the immunoglobulin superfamily that functions primarily as a cell adhesion molecule [8, 10]. The specific epitope defined by the monoclonal antibody 8019 is a highly tumor-restricted site on the CEA protein, notably absent from normal adult tissues and other CEA family members like the non-specific cross-reacting antigen (NCA) [3, 5]. In malignant cells, CEACAM5 is often overexpressed and loses its polarized distribution, contributing to tumor progression by promoting cell-cell adhesion and providing resistance to anoikis, or cell death induced by detachment [9, 12]. This specific 8019 epitope has served as the basis for the development of the anti-idiotype vaccine 3H1 (CeaVac), which acts as a functional mimic of the epitope to stimulate the patient's immune system against CEA-positive tumors [3, 4]. Targeting this epitope is particularly relevant in the treatment and imaging of colorectal, pancreatic, and lung adenocarcinomas, where high CEA expression correlates with poor prognosis and metastatic potential [1, 6, 10]. Clinical monitoring of serum CEA levels and tissue expression remains a standard practice for assessing treatment efficacy and disease recurrence in these patients [9, 10].

Other names

CEACD66eCarcinoembryonic antigenMeconium antigen 1008019 epitopeCarcinoembryonic antigen epitope 8019

The anti-idiotype vaccine 3H1 (CeaVac) mimics the 8019 epitope to induce an active immune response (Ab3) against CEA-expressing tumor cells, while the mAb 8019 itself binds directly to the epitope for potential therapeutic or diagnostic applications.