PSA is a 237-amino acid protein with a single N-glycosylation site. In contrast to PSA from normal cells that contain a dibranched carbohydrate at the glycosylation site, PSA from cancerous cells contains tri- and tetrabranched glycans. However, current assays for PSA employ antibodies against peptide epitopes only and are thus unable to distinguish between normal and “transformed” PSA. This invention consists of normal and transformed PSA glycans and glycopeptides, as well as methods for their synthesis.
Current PSA tests have low specificity. Antibodies against specific glycoforms of PSA developed with the use of this invention could lead to improved tests for prostate cancer and allow earlier diagnosis of the disease and monitoring of its likely aggressiveness.
Research tool for producing antibodies against different glycoforms of PSA that can be used for diagnostics and prognostics
Different glycoforms of PSA have been synthesized and are being used to immunize animals with the goal of producing selective antibodies.
Samuel Danishefsky, PhD, Laboratory Head, Molecular Pharmacology & Chemistry Program, Sloan Kettering Institute, Memorial Sloan Kettering
Dudkin VY, et al. (2004) J Am Chem Soc. 126(3):736-8