DPH1 and ovarian cancer: Notably, diphthamide has previously been linkedto cancer, with the DPH1 gene initially identifiedas a tumor suppressor gene (OVCA1); heterozygosityloss of OVCA1 has been associated with various cancers,particularly ovarian cancer.24,27,37 Given that genomic instability resulting from DNA damage and DNAreplication stress is associated with cancer progressions,4,38 our results provide a potential explanation for how diphthamidedeficiency promotes tumors (Figure 7C).