Funded by the Hearst Foundation
Tumors that spread to the brain, called brain metastases, are the cause of death of half of patients with metastatic melanoma. The metabolic environment of the brain is uniquely low in two amino acids, serine and glycine, which carry messages between nerve cells. This ensures accurate nerve cell communication, but should prevent or slow the growth of tumors, as tumor cells need large amounts of serine and glycine to make DNA and proteins to divide and grow. Yet, tumors can spread to the brain, and are incurable once they have done so.
We hypothesize that tumors metabolically adapt to the brain’s metabolic environment by increasing their ability to make serine and its product glycine, and that blocking the production of serine should either attenuate the development of brain metastases or help treat existing brain metastases. We will determine if serine synthesis is increased in brain metastases, and if tumor cells adapt to, or are selected for, the environment of the brain by increasing their production of serine and glycine. In addition, we have developed small molecules that inhibit serine synthesis, and will test these compounds in mouse models of melanoma brain metastases with the goal of reducing their initiation or growth. These studies will demonstrate that targeting the serine synthesis pathway might be useful in treating melanoma brain metastases and offer proof of concept that small molecule inhibitors of serine synthesis might be effective in treating patients with melanoma brain metastases and brain metastases from other tumors.