Abstract: Background and purpose: Sirtuin 6 (SIRT6) is an important histone modifying protein that is implicated in diverse physiological processes, as well as aging-associated diseases, and regulates DNA repair, energy metabolism and target gene expression. However, the role of SIRT6 in human osteosarcoma has not been fully understood. This study investigated the effect of the small interfering RNA (siRNA)-mediated SIRT6 knockdown on the survival and invasion. Methods: The siRNA against SIRT6 was constructed and transfected into U2OS cell line with Lipofectamine^TM 2000. The expression of SIRT6 was detected by Western blot. Flow cytometry was used to detect the cell apoptosis. Proliferation of cells was assayed using the cell counting kit-8 (CCK-8) method. The Transwell test was used to detect the invasion and migration ability of U2OS cells. And the viability in taxol was detected using CCK-8 method. Results: Compared with the control group, the protein level was significantly decreased in the experimental group at 24, 48 and 72 hours after transfection with SIRT6 siRNA. Flow cytometry detection showed the apoptotic rate increased significantly in the experimental group (P<0.05). Cell invasion and migration ability in the experimental group decreased significantly (P<0.05). In addition, the experimental group showed decreased growth after exposure to taxol compared with the control group (P<0.05). Conclusion: Down-regulation of SIRT6 expression may decrease invation and migration, promote apoptosis, and enhance the sensitivity to Taxol in U2OS osteosarcoma cell line.

Key words: SIRT6, Osteosarcoma, siRNA