A 62-year-old woman presents with a breast lump that she discovered 6 days ago. A breast biopsy shows lobular carcinoma in situ. Compared to normal epithelial cells of the breast lobule, these malignant cells would most likely show decreased expression of which of the following proteins?
High-Yield Explanation
Cadherins are Ca2+-dependent transmembrane glycoproteins that mediated cell-cell adhesion. E-cadherin is expressed on the surface of all epithelium and mediates cell adhesion by "zipper-like" interactions. -Desmin (choice A) is an intermediate filament protein found in cells of mesenchymal origin. -Lysyl hydroxylase (choice C) is involved in the post-translational modification of collagen. -P selectin is a cell adhesion molecule that mediates the margination of neutrophils during acute inflammation.