Synthesis and evaluation of anticancer vaccine candidates, c-glycoside Analogs of STn and PSA

Neuraminic acids are biologically important and occupy the terminal position of the glycoconjugate glycans on the outside of cells. Sialyl-Tn (sTn) is found on tumor-associated glycoprotein antigens present on the surface of cancer cells, including those associated with carcinomas of the breast, prostate, pancreas, colon, ovary, lung, and stomach. The sTn antigen is well known as a prognostic indicator and has proven to be an effective target for cancer therapy. Conjugate vaccines of sTn-KLH show remarkable immunogenicity, resulting in the production of both IgM and IgG type antibodies. The sTn C- glycoside was designed and synthesized and its KLH-conjugate was evaluated for immunogenicity in mice. Neuraminic acid C- glycosides such as sTn and polysialic acid (PSA) might be useful in preparing immunogens for active immunization against neuraminic acid containing glycoconjugates in the design and preparation of anti-cancer vaccines.