Immune System and Immune Checkpoints
The immune system plays a dual role against cancer: it prevents tumor cell outgrowth and also sculpts the immunogenicity of the tumor cells. Cancer cells are able to escape from the immune system by inhibiting T lymphocytes activation. New immunotherapies have been developed to target these T lymphocytes activation modulators: the immune checkpoints, defined as molecules of immune system that either turn up a signal or turn down a signal. Most of the cancers protect themselves from immune system by inhibiting activation of T cell.
These novel therapies are showing promising results with durable objective responses in some patients. Ipilimumab (anti-CTLA4) was the first of these new therapeutics to be approved by the FDA in March 2 11 for advanced melanoma and other immunomodulators trials are ongoing in other cancers with similar encouraging results like with the anti PD-1/PD-L1. These drugs are already challenging our future practice like for evaluation of tumor response or for management of immune related toxicities. Many immune checkpoints have been identified and could potentially be targeted. Future studies will help to identify predictive factors but also to coordinate these new immunotherapies with our classic treatment strategies.