EIF5A and cancer: eIF5A, particularly eIF5A2, is usually overexpressed in various types of cancer, while its activation due to spermidine-mediated hypusination through the action of two highly specialized enzymes, DHPS and DOHH, plays a critical role in regulating cell proliferation, apoptosis, EMT process, CSC properties, and metastasis of cancer cells [27, 48–51].