Narrower insight to SIRT1 role in cancer: A potential therapeutic target to control epithelial–mesenchymal transition in cancer cells

The epithelial-mesenchymal transition (EMT) is a highly networked cellular process which involves cell transition from the immotile epithelial to the motile mesenchymal phenotype, whereby cells lose their cell-cell adhesion and cell polarity. This important process is one of the underlying mechanisms for enabling invasion and metastasis of cancer cells which is considered as malignant phase of tumor progression. However, the molecular mechanisms of this process are not fully clarified. It is reported that Sirtuin1 (SIRT1), a NAD+ dependent class III histone deacetylase is associated with tumor metastasis through positive regulation of EMT in several types of cancers. Recent studies confirmed that up and down regulation of SIRT1 expression remarkably change the migration ability of different cancer cells in vitro and tumor metastasis in vivo. Also, according to this fact that carcinomas as the main human solid tumors, originate from different epithelial cell types, SIRT1 role in EMT has received a great attention due to its potential role in tumor development and metastasis. Therefore, SIRT1 has been proposed as a key regulator of cancer metastasis by promoting EMT, although little is known about the cleared effect of SIRT1 in this transition. Our aim in this review is to explain in more detail the role of SIRT1 in various signaling pathways related to carcinogenesis, with the focus on the promoting role of SIRT1 in EMT as a potential therapeutic target to control EMT and to prevent cancer progression.