MYC and neoplasm: SIRT6 regulates glucose homeostasis by modulating histone acetylation.139 SIRT6 interacts directly with HIF1 and MYC, and it functions as a co-repressor through histone deacetylation, thereby inhibiting transcription.139, 140, 141, 142 SIRT6 hence acts as a tumor suppressor by repressing HIF-dependent glycolytic switch and MYC-dependent ribosome biogenesis and glutaminolysis.