Abstract
Human polymorphic epithelial mucin is a high-molecular-mass glycoprotein that associates to provide protection to the epithelial-cell surface and may afford the malignant cell a selective advantage for growth. The scanning-tunnelling-microscopy micrographs obtained in the present study identify the purified human ovarian-carcinoma polymorphic epithelial mucin glycoproteins as rod-shaped molecules of mixed length. The dimensions of the individual molecules range from 25 to 45 nm in length and are 3-4 nm in width. The images further suggest that lateral association of the rods occurs.