Saporins are ribosome inactivating proteins, cell toxins which are found in species of the Saponaria family. In nature they serve cell defence systems for protection of plants against fungal, and bacterial attacks. In cancer cells, saporins can be used to cause apoptosis activation, oxidative stress, and the inhibition of protein synthesis. For this reason RIBs are being investigated for cancer therapy. Vaccaria hispanica is a good source of these kind of RIBs for medical research.