Zhao Xinyu, Yin Xuebei
Department of Clinical Laboratory, Qilu Hospital (Qingdao), Cheeloo College of Medicine, Shandong University, Qingdao, Shandong, China.
Center of Clinical Laboratory, Suzhou Dushu Lake Hospital, The Fourth Affiliated Hospital of Soochow University, 9 Chongwen Road, 215000, Suzhou, Jiangsu, China.
Biochem Genet. 2024 Dec 13. doi: 10.1007/s10528-024-10995-z.
Endometrial cancer (EC) is one of the three most common malignancies of the female reproductive system. SIRT3 is an NAD+-dependent protein deacetylase that maintains the stability of the intracellular environment. This study aims to investigate the mechanism of SIRT3 in regulating apoptosis in endometrial cancer and further reveal the role of SIRT3 in endometrial cancer. Differential expression of SIRT3 in tumors was analyzed by GEPIA using TCGA database data. Meanwhile, mRNA and protein expression levels of SIRT3 in tissues and cells were examined using RT-qPCR, Western Blot, and immunohistochemistry. The expression of SIRT3 after estradiol (E2) stimulation of Ishikawa cells was detected using RT-qPCR and Western Blot techniques. The effect of transfection after SIRT3 knockdown and overexpression was verified using RT-qPCR and Western Blot. Flow cytometry and TUNEL assay were used to detect the effect of SIRT3 on apoptosis. Reactive oxygen species (ROS) was used to detect the effect of SIRT3 on the level of oxidative stress in cells. The expression of apoptotic protein (BAX, cleaved-Caspase 3) and autophagy protein (cyto C and LC3A) were detected in transfected Ishikawa cell. Differences analysis of TCGA database data showed that the expression of SIRT3 in EC was significantly lower than that in normal endometrial tissue. The mRNA and protein levels of SIRT3 were significantly lower in EC tissues or cells than normal controls. E2 stimulation in Ishikawa cells resulted in the down-regulation of SIRT3 expression. After transfection, SIRT3 promoted the apoptosis of Ishikawa cells and attenuated the levels of ROS. Overexpression of SIRT3 promoted apoptosis and autophagy-related proteins. Thus, high expression of SIRT3 inhibits the development of EC whereas low expression of SIRT3 may promote the progression of EC, which provides a new direction for studying the treatment of EC.
子宫内膜癌（EC）是女性生殖系统最常见的三种恶性肿瘤之一。SIRT3是一种依赖烟酰胺腺嘌呤二核苷酸（NAD+）的蛋白质脱乙酰酶，可维持细胞内环境的稳定性。本研究旨在探讨SIRT3调节子宫内膜癌细胞凋亡的机制，并进一步揭示SIRT3在子宫内膜癌中的作用。利用GEPIA通过癌症基因组图谱（TCGA）数据库数据分析肿瘤中SIRT3的差异表达。同时，采用逆转录定量聚合酶链反应（RT-qPCR）、蛋白质免疫印迹法（Western Blot）和免疫组织化学法检测组织和细胞中SIRT3的mRNA和蛋白质表达水平。采用RT-qPCR和Western Blot技术检测雌二醇（E2）刺激子宫内膜癌细胞系（Ishikawa细胞）后SIRT3的表达情况。采用RT-qPCR和Western Blot验证SIRT3基因敲低和过表达后转染的效果。采用流式细胞术和末端脱氧核苷酸转移酶介导的缺口末端标记法（TUNEL法）检测SIRT3对细胞凋亡的影响。采用活性氧（ROS）检测SIRT3对细胞氧化应激水平的影响。检测转染后的Ishikawa细胞中凋亡蛋白（BAX、裂解的半胱天冬酶3）和自噬蛋白（细胞色素C和微管相关蛋白1轻链3A（LC3A））的表达。TCGA数据库数据分析结果显示，EC中SIRT3的表达显著低于正常子宫内膜组织。EC组织或细胞中SIRT3的mRNA和蛋白质水平显著低于正常对照。E2刺激Ishikawa细胞导致SIRT3表达下调。转染后，SIRT3促进Ishikawa细胞凋亡并降低ROS水平。SIRT3过表达促进凋亡和自噬相关蛋白表达。因此，SIRT3高表达抑制EC的发展，而SIRT3低表达可能促进EC的进展，这为研究EC的治疗提供了新方向。
