SIRT5 and colorectal carcinoma: To validate this hypothesis, we performed the 5-ethynyl-20-deoxyuridine (EdU) assay, and found that inhibition of DNA synthesis induced by SIRT5 knockdown was reversed by supplementation with nucleosides in different CRC cell lines (HCT116, LoVo, and HT29) using immunofluorescence and flow cytometry analysis (Fig. 2i–l and Supplementary Fig. 3a–d).