CAJ | 학술논문

背景与目的:组蛋白去乙酰化酶1(sirtuin type 1,SIRT1)在胰腺癌等恶性肿瘤中高表达,可能与肿瘤的恶性表型相关.本研究采用RNA干扰技术下调胰腺癌PANC1细胞中SIRT1的表达,探讨其对DNA损伤修复及放化疗抵抗的影响.方法:用彗星试验检测细胞敲除SIRT1后DNA损伤修复能力;蛋白质印迹法(Western blot)检测NBS1、γH2AX DNA修复相关蛋白的表达水平;最后用克隆存活实验和细胞增殖实验观察胰腺癌细胞对放化疗的敏感性.结果:下调SIRT1显著抑制了胰腺癌细胞的DNA损伤修复能力;抑制了DNA损伤修复相关蛋白NBS1磷酸化活化;增强了细胞对放化疗的敏感性.结论:SIRT1基因表达下调可抑制胰腺癌细胞DNA损伤修复能力,提高其对放化疗的敏感性,机制上可能与SIRT1下调后NBS1磷酸化活化受抑制相关.
배경여목적:조단백거을선화매1(sirtuin type 1,SIRT1)재이선암등악성종류중고표체,가능여종류적악성표형상관.본연구채용RNA간우기술하조이선암PANC1세포중SIRT1적표체,탐토기대DNA손상수복급방화료저항적영향.방법:용혜성시험검측세포고제SIRT1후DNA손상수복능력;단백질인적법(Western blot)검측NBS1、γH2AX DNA수복상관단백적표체수평;최후용극륭존활실험화세포증식실험관찰이선암세포대방화료적민감성.결과:하조SIRT1현저억제료이선암세포적DNA손상수복능력;억제료DNA손상수복상관단백NBS1린산화활화;증강료세포대방화료적민감성.결론:SIRT1기인표체하조가억제이선암세포DNA손상수복능력,제고기대방화료적민감성,궤제상가능여SIRT1하조후NBS1린산화활화수억제상관.
@@@@Background and purpose:SIRT1 is widely up-regulated in different cancers including pancreatic cancer (PC) and may be involved in the cellular malignant transformation. This study was designed to investigate the effects of down-regulated SIRT1 expression on the DNA damage repair capacity as well as chemoradiosensitivity of PC cells. Methods:DNA damage repair was analyzed by comet assay under the condition of SIRT1 suppression. Western blot was performed to investigate the expression of DNA repair associated proteins including, NBS1 and γH2AX. Clonogenic survival assay and MTT assay were used to detect the chemoradiosensitivity following SIRT1 silencing. Results:Knockdown of SIRT1 significantly impaired DNA damage repair capacity while increased the sensitivity of PANC1 cells to radiation and chemotherapy. Mechanically, down-regulation of SIRT1 inhibited NBS1 activation in the presence of DNA damage repair. Conclusion:Down-regulated SIRT1 expression inhibits the activation of NBS1 and thus is involved in DNA damage repair arrest and restoration of chemoradiosensitivity.