Antigens are the key
Cancer immunotherapy is a potential new approach for treating cancer using our own immune system to fight cancer.
To attack cancer cells, our immune system has to recognize something on the cells that makes them different from normal, non-cancerous cells. These substances on the surface of cancer cells are called “cancer antigens”. Cancer antigens can be particular to cancer cells (cancer-specific), merely different from normal cells or more present in the cancer cells than in normal cells.
GlaxoSmithKline (GSK) is developing an immunotherapy based approach (or immunotherapeutic) that uses these cancer antigens. It is called ASCI, which stands for Antigen-Specific Cancer Immunotherapeutics. This new therapy which is currently in development is given by injection into muscle.
The principle behind ASCI is that any cancer is associated with an antigen that is displayed on the surface of its cells and that ASCI will target only the antigen that is on the cancer cell. It is envisioned that as a result of stimulation of the immune system with ASCI, the immune system will only react to the cancer cell that displays the antigen and will have no effect on the normal cells.
The first antigen that has entered into late stage clinical development of an ASCI is called MAGE-A3, a cancer-specific antigen found in several types of cancer including lung cancer, melanoma (skin cancer) and bladder cancer.
Boosted by Adjuvant System
However, to make the ASCI approach to immunotherapy work more effectively, the reaction of the immune system has not only to be triggered by the antigen but also must be boosted to make it strong enough to detect and destroy cancer cells.
This is achieved by combining the antigen as well as a substance called an “Adjuvant System” together to create the ASCI: ASCI is an “antigen-adjuvant” combination that may make a difference in using immunotherapy for cancer treatment.
Recent discoveries have shown that particular Adjuvant Systems can be used to regulate and re-activate our immune system, potentially making ASCI treatment more effective.
ASCI treatment combining cancer antigens and an Adjuvant System is currently being tested against several specific types of cancer.
