Methylation modifications play pertinent roles in regulating gene expression and various biological processes. The silencing of the demethylase enzyme TET1 can affect the expressions of key oncogenes or tumour suppressor genes, thus contributing to tumour formation. Nonetheless, how TET1 affects the progression of cervical cancer is yet to be elucidated. In this study, we found that the expression of TET1 was significantly downregulated in cervical cancer tissues. Functionally, TET1 knockdown in cervical cancer cells can promote cell proliferation, migration, invasion, cervical xenograft tumour formation and EMT. On the contrary, its overexpression can reverse the aforementioned processes. Moreover, the autophagy level of cervical cancer cells can be enhanced after TET1 knockdown. Mechanistically, methylated DNA immunoprecipitation (MeDIP)-sequencing and MeDIP quantitative real-time PCR revealed that TET1 mediates the methylation of autophagy promoter regions. These findings suggest that TET1 affects the autophagy of cervical cancer cells by altering the methylation levels of NKRF or HIST1H2AK, but the specific mechanism needs to be investigated further.

The aging process of the kidneys is accompanied with several structural diseases. Abnormal fiber formation disrupts the balance of kidney structure and function, causing to end-stage renal disease and subsequent renal failure. Despite this, the precise mechanism underlying renal damage in aging remains elusive. In this study, ABI3BP gene knockout mice were used to investigate the role of ABI3BP in renal aging induced by irradiation. The results revealed a significant increase in ABI3BP expression in HK2 cells and kidney tissue of aging mice, with ABI3BP gene knockout demonstrating a mitigating effect on radiation-induced cell aging. Furthermore, the study observed a marked decrease in Klotho levels and an increase in ferroptosis in renal tissue and HK2 cells following irradiation. Notably, ABI3BP gene knockout not only elevated Klotho expression but also reduced ferroptosis levels. A significant negative correlation between ABI3BP and Klotho was established. Further experiments demonstrated that Klotho knockdown alleviated the aging inhibition caused by ABI3BP downregulation. This study identifies the upregulation of ABI3BP in aged renal tubular epithelial cells, indicating a role in promoting ferroptosis and inducing renal aging by inhibiting Klotho expression.

Doxorubicin (DOX) is a commonly used antitumor drug, but its application has been limited because of its strong cardiac damage. This study aims to explore the role of NSUN2 in DOX-induced heart injury. C57BL/6J mice were intraperitoneally injected with 20 mg/Kg DOX to induce heart injury. After 3 days, the cardiac function, cardiac histopathology, myocardial apoptosis, and the expression level of NSUN2 were detected. In vitro, H9C2 cells were transfected with NSUN2 siRNA or overexpressed lentivirus and then treated with 500 ng/ml DOX. After 24 h, the changes in reactive oxygen species (ROS), apoptosis, and NSUN2 expression were detected. After DOX treatment, both in vitro and in vivo experiments showed that the cardiac function decreased, the number of apoptotic cells increased, and the expression level of NSUN2 increased. Interfering the expression of NSUN2 by siRNA promoted DOX-induced heart injury, while overexpression of NSUN2 could inhibit DOX-induced heart injury. Further study showed that NSUN2 promoted antioxidative stress by upregulating the Nrf2 protein level. In addition, NSUN2 overexpression could increase the half-life of Nrf2 mRNA. m5C RNA methylation immunoprecipitation (MeRIP) also showed that the level of Nrf2 m5C mRNA was significantly increased in NSUN2 overexpressed group when compared to the GFP group. NSUN2 enhances the expression of Nrf2 by promoting Nrf2 mRNA m5C modification and enhances its antioxidative stress effect to alleviate DOX-induced myocardial injury.

目的 研究小鼠急性心肌梗死(AMI)后不同时间点心肌组织自噬水平的动态变化.方法 选取8～10周龄SPF级C57BL/6J野生型小鼠40只,随机分为假手术组(Sham组)、AMI组(永久结扎左前降支),每组20只,分别于术后7、14、28 d时,用心脏超声检测心脏功能及结构变化,Masson染色观察小鼠梗死周边心肌组织纤维化,Western blot检测自噬蛋白、透射电镜观察自噬小体、免疫组织化学检查凋亡蛋白表达.结果 Masson染色显示,AMI组梗死周边组织间质纤维化随着时间的推移加重;AMI组7、14和28 d时Bax蛋白较Sham组明显上调(0.71±0.08、0.77±0.05和0.86±0.06 vs 0.53±0.08,P＜0.05),Bcl-2和自噬微管相关蛋白轻链3蛋白降低(P＜0.05),P62蛋白表达增强(P＜0.05);透射电镜示,AMI组梗死周边心肌组织内 自噬小体数量明显减少.结论 小鼠AMI后梗死周边心肌组织自噬水平进行性降低,心室重构进一步恶化,自噬可能在AMI中起保护作用.