Mucin 1 (MUC1) is a protein that is commonly found on the surface of epithelial cells in various organs, including the lungs, gastrointestinal tract, and breast tissue. It plays a crucial role in protecting and lubricating the epithelial cells, as well as being involved in cell signaling and immune response. Research on MUC1 has focused on its role in cancer, as abnormalities in MUC1 expression or structure have been associated with various types of cancer, including breast, lung, and pancreatic cancer. Studies have explored the potential of targeting MUC1 for cancer therapy, as well as using MUC1 as a biomarker for cancer diagnosis and prognosis. Overall, research on MUC1 spans multiple disciplines, including oncology, immunology, and molecular biology, and continues to uncover new insights into the role of this protein in health and disease.