Like many cancers, melanomas look like healthy cells to our immune system. But melanomas have unique protein fragments (peptides) on their cell surfaces that make them stand out from normal cells. A new study suggests that our immune systems can be redirected to target these cancer-specific peptides — and so melanomas. In an ongoing phase I clinical trial, the researchers found that an anti-melanoma vaccine shrank tumors in both of the people with melanomas that had spread. One of these people now has no evidence of melanoma.