Cancer Vaccine Adjuvant: Annexin II (20100242)

Annexin II Increases MHC I Expression on Tumor Cells

The protein Annexin II can work through a mechanism to boost immunotherapy treatments. Annexin II possesses attributes which makes it desirable as a cancer vaccine adjuvant - it selectively increases the shuttling of exogenous antigen to the major histocompatibility complex class 1 (MHC I) pathway, a key antigen-presenting process associated with tumor killing; it increases the expression of inflammatory cytokines associated with cellular immune responses; and it also decreases the expression of cytokines which are known to suppress immune responses associated with tumor killing. Finally, Annexin II appears to act in a synergistic manner with other vaccine adjuvants, such as CpG, to enhance tumor killing in breast and brain cancer models.

Annexin II as an Immune Response Modifier

Lack of drug efficacy, and/or the development of drug resistance, is a common challenge in the field of oncology. There is a real need for therapeutics that can overcome these problems, and make tumor cells susceptible to killing. Researchers have been investigating the use of immunotherapy for this purpose - with the ultimate goal of training the patient’s own immune system to seek out and destroy the cancer. One major hurdle to this approach is that cancer is viewed as “self” by the immune system, and is very poor at stimulating a strong immune response. Vaccine “adjuvants” are needed which selectively, potently, and efficiently activate the appropriate arm of the immune system associated with tumor killing.

BENEFITS OF ANNEXIN II TO BOOST IMMUNOTHERAPY TREATMENTS

• As an immunotherapy agent, Annexin II is a native protein that is useful in the targeted delivery of therapy
• Increases antigen expression on MHC I providing a adjuvant effect to increase cellular immune response
• Increases the efficacy of vaccines that rely on CD8+ T cell responses
• Down-regulates “suppressor” cytokines and increases “inflammatory” cytokines, boosting the development of the immune arm associated with tumor killing
• Effective as a “single” agent and has synergistic effects with other adjuvants if necessary