Labyrinthin (LAB)

Labyrinthin is a 40 kDa tumor-associated cell surface antigen that is highly specific to adenocarcinomas, including those of the lung, breast, and colon (Barsky et al., 1997). It is encoded by the aspartyl/asparaginyl beta-hydroxylase (ASPH) gene but exists as a distinct, truncated isoform that localizes to the external cell membrane (Sprenger et al., 2001). In normal tissues and non-adenocarcinoma cancers, labyrinthin expression is virtually undetectable, making it a highly selective biomarker and therapeutic target (Radosevich et al., 1991). Biologically, the protein is involved in promoting the invasive and metastatic potential of tumor cells, likely through its role in cell signaling and migration (Barsky et al., 1997). Therapeutic strategies targeting labyrinthin include the monoclonal antibody MCA 44-3A6, which has been used for diagnostic imaging and as a potential vehicle for drug delivery, and the Lab-1 peptide vaccine designed to elicit a T-cell mediated immune response against adenocarcinoma cells (Zhu et al., 2007).

Other names

LAB44-3A6 antigenAdenocarcinoma-associated antigenASPH-related protein

Targeted immunotherapy via monoclonal antibody binding for tumor detection and destruction, or induction of antigen-specific T-cell responses through peptide vaccination (Zhu et al., 2007; Radosevich et al., 1991).