沉默信息调节因子（silence information regulator，sirtuin）是一类高度保守的烟酰胺腺嘌呤二核苷酸（NAD+）依赖的组蛋白去乙酰化酶，在衰老、代谢、细胞凋亡、基因转录、炎症发生等过程中发挥重要作用。哺乳动物有 7种 sirtuin，即 SIRT1～ SIRT7。其中 SIRT2的异常表达与包括肝癌在内的多种癌症相关： SIRT2既可以发挥癌基因的作用，也可以发挥抑癌基因的作用。而 SIRT2如何通过对不同底物去乙酰化发挥不同的作用仍然存在争议。该文主要对 SIRT2在肝癌发生发展中的作用进行综述。

Silence information regulators (sirtuins) are highly conserved nicotinamide adenine dinucleotide (NAD+) dependent histone deacetylases, which play important roles in the process of aging, metabolism, apoptosis, gene transcription, and inflammation. There are seven kinds of sirtuins in mammals, SIRT1-SIRT7. These proteins have different subcellular localization and play diverse roles in metabolism. SIRT2, one of the members of sirtuins family, is mainly located in the cytoplasm and participates in the cell cycle control, oxidative stress and glycolipid metabolism. In addition, the level of SIRT2 has been widely associated with the development of cancers, including hepatocellular carcinoma. SIRT2 possesses a dual role in tumorigenesis, with both tumor-promoting and tumor-suppressing function. However, the mechanisms in which SIRT2 plays the roles in cancer are still controversial. In this review, the conflicting roles of SIRT2 in the tumorigenesis and development of hepatocellular carcinoma were mainly discussed.