Vaccines harness the immune system to keep people safe from infectious diseases. Thanks to broad-based vaccination programs, some of the most terrifying diseases in history, small pox and polio among them, have been eliminated from existence. Unfortunately, there’s been little success developing a preventative (prophylactic) vaccine against cancer.
Vaccines work by exposing to an individual’s immune system a benign form of a disease agent. The immune system identifies the agent and learns to attack and destroy it, retaining a memory of the agent so the immune system knows to react if an individual is exposed to the disease agent months or years later.
Most vaccines attack pathogens, such as viruses and bacteria. The immune system is better able to assail these agents because they come from outside the body. Cancer, however, is a different matter. The disease is caused by aberrant cells that arise out of our resident cells. That can make it difficult for our immune system to find the diseased cells, especially as advancing age weakens our immune system. Once these aberrant cells gain critical mass, they become cancer.
Despite the lack of success with cancer vaccines, recently gained knowledge about the human immune system has led to the development, approval and commercialization of revolutionary immuno-therapy drugs. These drugs do not attack cancer directly, but rather modulate the immune system in ways that enable it to destroy or dramatically impair cancer cells.
Imagine if we could train the immune system to kill cancer cells as they arise before they form into tumors. Perhaps, we could eliminate the onset of cancer. The difficulty has been to identify an agent that allows the immune system to target malignant cells without harming healthy tissue.
Cleveland Clinic researchers have identified a protein called alpha-lactalbumin that is present in healthy breast tissue only when a woman is lactating and disappears when she stops nursing her child. Alpha-lactalbumin is never present on any other cell in the body. However, it does show up in many types of breast cancer, including an aggressive and deadly form of the disease known as Triple Negative Breast Cancer (TNBC).
In addition, Cleveland Clinic researchers have identified that the extracellular domain of anti-Mullerian hormone receptor II (AMHR2-ED) is expressed in normal ovaries, and nowhere else in the body, with this expression ceasing after menopause. However, this protein is also expressed in cancerous ovary cells.
By developing vaccines that target alpha-lactalbumin and AMHR2-ED, we feel the immune system can destroy breast cancer cells and ovarian cancer cells, respectively, as they arise and ultimately prevent tumors from forming.
Following the positive clinical data seen in the breast cancer vaccine Phase 1 clinical trial, we have commenced, in collaboration with Cleveland Clinic, a cancer vaccine discovery program utilizing the same mechanism as our breast and ovarian cancer vaccines, to develop additional cancer vaccines to address many intractable cancers, including high incidence malignancies in lung, colon, and prostate.