- Breast carcinoma epithelial cells express a very low-density lipoprotein receptor variant lacking the O-linked glycosylation domain encoded by exon 16, but with full binding activity for serine proteinase/serpin complexes and Mr-40,000 receptor-associated protein. Martensen, P.M., Oka, K., Christensen, L., Rettenberger, P.M., Petersen, H.H., Christensen, A., Chan, L., Heegaard, C.W., Andreasen, P.A. Eur. J. Biochem. (1997)