Neurophysin-related cell surface antigen (NRSA)

The neurophysin-related cell surface antigen (NRSA) is a tumor-specific marker derived from the pro-vasopressin (Pro-AVP) precursor protein [1, 2]. In normal physiology, the AVP gene is expressed in the hypothalamus, where the resulting pro-hormone is cleaved into arginine vasopressin, neurophysin II, and copeptin [2]. However, in small cell lung cancer (SCLC) and certain breast cancers, the pro-vasopressin precursor is often incorrectly processed and becomes localized to the outer plasma membrane of the tumor cells [1, 11]. This aberrant surface expression makes NRSA an attractive target for monoclonal antibodies, such as MAG-1, which can selectively bind to the tumor cells without affecting normal tissues [1, 5]. Binding of MAG-1 to NRSA leads to the internalization of the antibody-antigen complex and can trigger apoptosis or be used to deliver radioisotopes directly to the tumor [5]. Furthermore, the presence of NRSA and its related peptides in the blood can serve as valuable biomarkers for diagnosing SCLC and monitoring the efficacy of treatment [3, 11]. The target is particularly significant because it is expressed in both primary and recurrent SCLC, providing a potential therapeutic avenue for a disease with limited treatment options [5].

Other names

Pro-vasopressinPro-AVPGlycopeptide-related cell surface antigenGRSAVasopressin-associated human neurophysin surface antigenVP-HNP surface antigen

Monoclonal antibody binding to the surface-expressed pro-vasopressin precursor, leading to internalization and induction of apoptosis or delivery of cytotoxic isotopes.