Therapeutic cancer vaccines can slow or stop cancer growth, shrink tumors, prevent cancer from returning, and even kill cancer cells that cannot be killed by other means. In order for a therapeutic cancer vaccine to work, it needs to stimulate a targeted and specific immune response, and recognize cancer cells that are being evasive. Cancer cells can have different evasion strategies. One strategy is that cancer cells carry normal self-antigens, and T cells that will recognize self are eliminated during negative selection. Another strategy is that while cancer cells do have cancer associated antigens, these antigens can be removed when the cells mutate. A third strategy is that cancer cells can suppress the CTLs. As a result, few cancer cells can escape detection from the immune system. When that happens, the cancer cells can multiply and overwhelm the immune system.
Currently, the only therapeutic cancer vaccine that is approved by the FDA is sipuleucel-T, which is a customized treatment for men that have metastatic prostate cancer. However, there are many other therapeutic cancer vaccines that are in the clinical trial stage, such as vaccines against bladder cancer, brain tumors, breast cancer, cervical cancer, Hodgkin lymphoma, kidney cancer, leukemia, lung cancer, melanoma, multiple myeloma, non-Hodgkin lymphoma, pancreatic cancer, and prostate cancer.
Therapeutic cancer vaccines can be combined with other cancer treatment options such as surgery, chemotherapy, and radiation therapy. Surgical removal of large portions of tumors can then help the vaccine work more efficiently, by allowing the vaccine to focus on the hard to remove tumors. Currently, there are clinical trials investigating when best to administer the therapeutic cancer vaccines: before, during, or after chemotherapy.
If you would like to learn more about Therapeutic Cancer Vaccines, please check out this article.