Mucin-1 cleavage product (MUC1*) (MUC1* (for the cleaved form))

Mucin-1 (MUC1) is a large, highly glycosylated transmembrane glycoprotein that is normally expressed on the apical surface of epithelial cells; in cancer, it is overexpressed and aberrantly glycosylated. MUC1 cleavage product—commonly designated MUC1*—refers to a membrane-associated fragment produced by proteolytic cleavage of full-length MUC1 at a specific SEA domain cleavage site[4]. This cleaved form (MUC1*) is enriched on the surface of many tumor cells, where it functions as a growth factor receptor and signaling mediator[2][1]. Specially developed antibodies (e.g., MNC2) and cell therapies (CAR T cells) can selectively recognize MUC1* but not full-length MUC1, enabling tumor targeting while sparing normal tissue[1]. The presence of MUC1* has been associated with tumor progression, cell proliferation, and is being developed as a novel immunotherapy and biomarker for cancers such as breast and ovarian carcinoma[2][1]. MUC1*’s unique prevalence and distribution on tumor cells, along with its functional role in oncogenesis, make it a therapeutic target and potential diagnostic biomarker in oncology.

Other names

Tumor-associated mucin 1 cleavage productMUC1*Tumor-associated growth factor receptor form of MUC1Cleaved MUC1MUC1 cleavage product

Antibody-mediated recognition and killing of MUC1*-expressing tumor cells (e.g., CAR T-cells, monoclonal antibodies)[1] Blocking or modulating cell surface signaling mediated by MUC1* (hypothesized anticancer mechanism)