Human Mucin 1 (MUC1) Protein

Background

MUC1 (Mucin 1) is a large, transmembrane glycoprotein predominantly expressed on the surface of epithelial cells in various tissues, including the lungs, stomach, intestines, and the mammary glands. As a mucin protein, MUC1 plays a critical role in forming a protective mucous barrier on epithelial surfaces, which protects against environmental and microbial challenges. MUC1 also contributes to cell signaling and modulation of the immune response, particularly in epithelial cell inflammation. Due to its protective function on epithelial tissues, MUC1 expression is typically restricted to the apical surface of cells. However, in pathological states like cancer, MUC1 expression becomes dysregulated. Overexpression, aberrant glycosylation, and loss of polarity are commonly observed in many epithelial cancers, including breast, ovarian, and pancreatic cancers. These modifications contribute to tumor development, cancer cell survival, and metastasis, making MUC1 a key target for cancer diagnostics and therapeutics. In addition to cancer, MUC1 is associated with certain inflammatory and infectious diseases due to its role in the immune system.