SIRT3 and neoplasm: A variety of human tumors display reduced SIRT3 expression, supporting the hypothesis that sirtuin 3 (SIRT3) acts as a tumor suppressor in humans [37]; because the deacetylase enzyme SIRT3 targets enzymes that are involved in multiple mitochondrial oxidative pathways, with the cumulative effect of promoting nutrient oxidation and energy production, its anti-oncogenic activity may reside in enhancing oxidative metabolism to the detriment of the efflux of TCA cycle metabolites for anabolic purposes.