For example, the levels of succinylation and acetylation increase simultaneously in breast cancer tissues, and the 2 may be co-regulated by members of the histone deacetylase family.[57] Nucleophosmin 1(NPM1) is the only protein in which acetylation and succinylation occur at the same lysine site and is highly conserved in many distinct species. This evidence concerns the gene NPM1 and breast carcinoma.