SIRT5 and cancer: Thus, SUCLG2 regulates mitochondrial protein succinylation in a dual manner: on one hand, by hydrolyzing succinyl-CoA, it reduces succinylation levels and maintains the activity of key metabolic enzymes; on the other hand, its own succinylation enhances protein stability via the SIRT5-TRIM21 axis, forming a cancer-promoting positive feedback loop.