SIRT4 and cancer: Evidence has shown that SIRT2 promotes BRCA1-BRCA1-associated RING domain protein 1 (BARD1) heterodimerization through deacetylation, thereby facilitating homologous recombination and tumor suppression.407 Additionally, in cancer biology, Slug, an EMT transcription factor, promotes tumor progression and metastasis.408 In basal-like BC, SIRT2 maintains Slug protein stability by deacetylation, which contributes to basal-like BC’s robust tumorigenic activity, along with enhanced invasive and metastatic capabilities.409 SIRT3, SIRT4 and SIRT7 illustrate different functions in BC progression.