UNLABELLED: Sirtuin 1 (SIRT1) has been implicated in telomere maintenance and the growth of hepatocellular carcinoma (HCC). Nevertheless, the role of other sirtuins in the pathogenesis of HCC remains elusive. We found that sirtuin 2 (SIRT2), another member of the sirtuin family, also contributes to cell motility and invasiveness of HCC. SIRT2 is up-regulated in HCC cell lines and in a subset of human HCC tissues (23/45). Up-regulations of SIRT2 in primary HCC tumors were significantly correlated with the presence of microscopic vascular invasion (P = 0.001), a more advanced tumor stage (P = 0.004), and shorter overall survival (P = 0.0499). Functional studies by short hairpin RNA-mediated suppression of SIRT2 expression in HCC cell lines revealed significant inhibition of motility and invasiveness. Depletion of SIRT2 also led to the regression of epithelial-mesenchymal transition (EMT) phenotypes, whereas the ectopic expression of SIRT2 in the immortalized hepatocyte cell line L02 promoted cell motility and invasiveness. Mechanistic studies revealed that SIRT2 regulates the deacetylation and activation of protein kinase B, which subsequently impinges on the glycogen synthase kinase-3β/β-catenin signaling pathway to regulate EMT. CONCLUSIONS: Our findings have uncovered a novel role for SIRT2 in HCC metastasis, and provide a rationale to explore the use of sirtuin inhibitors in HCC therapy. (HEPATOLOGY 2013;).
UNLABELLED: Sirtuin 1 (SIRT1) has been implicated in telomere maintenance and the growth of hepatocellular carcinoma (HCC). Nevertheless, the role of other sirtuins in the pathogenesis of HCC remains elusive. We found that sirtuin 2 (SIRT2), another member of the sirtuin family, also contributes to cell motility and invasiveness of HCC. SIRT2 is up-regulated in HCC cell lines and in a subset of human HCC tissues (23/45). Up-regulations of SIRT2 in primary HCC tumors were significantly correlated with the presence of microscopic vascular invasion (P = 0.001), a more advanced tumor stage (P = 0.004), and shorter overall survival (P = 0.0499). Functional studies by short hairpin RNA-mediated suppression of SIRT2 expression in HCC cell lines revealed significant inhibition of motility and invasiveness. Depletion of SIRT2 also led to the regression of epithelial-mesenchymal transition (EMT) phenotypes, whereas the ectopic expression of SIRT2 in the immortalized hepatocyte cell line L02 promoted cell motility and invasiveness. Mechanistic studies revealed that SIRT2 regulates the deacetylation and activation of protein kinase B, which subsequently impinges on the glycogen synthase kinase-3β/β-catenin signaling pathway to regulate EMT. CONCLUSIONS: Our findings have uncovered a novel role for SIRT2 in HCC metastasis, and provide a rationale to explore the use of sirtuin inhibitors in HCC therapy. (HEPATOLOGY 2013;).
Authors: Sabine A S Langie; Gudrun Koppen; Daniel Desaulniers; Fahd Al-Mulla; Rabeah Al-Temaimi; Amedeo Amedei; Amaya Azqueta; William H Bisson; Dustin G Brown; Gunnar Brunborg; Amelia K Charles; Tao Chen; Annamaria Colacci; Firouz Darroudi; Stefano Forte; Laetitia Gonzalez; Roslida A Hamid; Lisbeth E Knudsen; Luc Leyns; Adela Lopez de Cerain Salsamendi; Lorenzo Memeo; Chiara Mondello; Carmel Mothersill; Ann-Karin Olsen; Sofia Pavanello; Jayadev Raju; Emilio Rojas; Rabindra Roy; Elizabeth P Ryan; Patricia Ostrosky-Wegman; Hosni K Salem; A Ivana Scovassi; Neetu Singh; Monica Vaccari; Frederik J Van Schooten; Mahara Valverde; Jordan Woodrick; Luoping Zhang; Nik van Larebeke; Micheline Kirsch-Volders; Andrew R Collins Journal: Carcinogenesis Date: 2015-06 Impact factor: 4.944
Authors: Osama Abo Alrob; Sowndramalingam Sankaralingam; Cary Ma; Cory S Wagg; Natasha Fillmore; Jagdip S Jaswal; Michael N Sack; Richard Lehner; Mahesh P Gupta; Evangelos D Michelakis; Raj S Padwal; David E Johnstone; Arya M Sharma; Gary D Lopaschuk Journal: Cardiovasc Res Date: 2014-06-25 Impact factor: 10.787