An experimental treatment made from a plant virus is effective at protecting against a broad range of metastatic cancers in mice, shows a new study from the University of California San Diego. The treatment, composed of nanoparticles fashioned from the cowpea mosaic virus—a virus that infects black-eyed pea plants—showed remarkable success in improving survival rates and suppressing the growth of metastatic tumors across various cancer models, including colon, ovarian, melanoma and breast cancer.