Li Wei, Huang Guo, Wei Jinrong, Cao Hong, Jiang Guoqin
Department of Surgery, The Second Affiliated Hospital of Soochow University, No. 1055, San-Xiang Road, Suzhou, 215004, Jiangsu, People's Republic of China.
Department of Breast and Thyroid Surgery, The Second Affiliated Hospital, Hengyang Medical College, University of South China, Hengyang, 421001, Hunan, People's Republic of China.
Mol Cell Biochem. 2023 Apr;478(4):729-741. doi: 10.1007/s11010-022-04541-x. Epub 2022 Sep 7.
As a critical catalytic subunit of N6-methyladenosine (m6A) modification in messenger RNA, ALKBH5 has been reported to affect the progression of numerous tumors. However, the functions and mechanisms of ALKBH5 in thyroid cancer remain largely unknown. Relative mRNA and protein levels in thyroid cancer tissues and cells were detected by qRT-PCR and western blot, respectively. The proliferation and viability were evaluated using colony formation and CCK-8 assays. Intracellular iron level was measured by an iron colorimetric assay kit. ROS level was determined using CellRox Green reagent. TIAM1 mRNA m6A level was detected by MeRIP. Xenograft tumor growth was performed to examine the role of ALKBH5 in thyroid tumor growth in vivo. ALKBH5 was decreased in thyroid cancer tissues and cells. ALKBH5 overexpression inhibited thyroid cancer cell proliferation and increased the levels of Fe and ROS and reduced the proteins expression of GPX4 and SLC7A11. Furthermore, overexpression of ALKBH5 inhibited TIAM1 expression by m6A modification, and overexpression of TIAM1 reversed the regulatory of oe-ALKBH5 on cell proliferation and ferroptosis in thyroid cancer. In addition, TIAM1 was elevated in thyroid cancer, and TIAM1 knockdown repressed thyroid cancer cell proliferation and promoted ferroptosis through regulating Nrf2/HO-1 axis. In addition, in vivo evidences also showed that ALKBH5 suppressed thyroid cancer progression by decreasing the m6A level of TIAM1. Our findings suggested that ALKBH5 inhibited thyroid cancer progression by inducing ferroptosis through m6A-TIAM1-Nrf2/HO-1 axis, suggesting ALKBH5 might be a potential target molecule for the treatment and diagnosis of thyroid cancer.
作为信使核糖核酸中N6-甲基腺苷（m6A）修饰的关键催化亚基，已有报道称ALKBH5会影响多种肿瘤的进展。然而，ALKBH5在甲状腺癌中的功能和机制在很大程度上仍不清楚。分别通过qRT-PCR和蛋白质免疫印迹法检测甲状腺癌组织和细胞中的相关信使核糖核酸和蛋白质水平。使用集落形成和CCK-8试验评估细胞增殖和活力。通过铁比色测定试剂盒测量细胞内铁水平。使用CellRox Green试剂测定活性氧水平。通过甲基化RNA免疫沉淀法（MeRIP）检测TIAM1信使核糖核酸的m6A水平。进行异种移植瘤生长实验以研究ALKBH5在体内甲状腺肿瘤生长中的作用。ALKBH5在甲状腺癌组织和细胞中表达降低。ALKBH5过表达抑制甲状腺癌细胞增殖，增加铁和活性氧水平，并降低GPX4和SLC7A11的蛋白质表达。此外，ALKBH5过表达通过m6A修饰抑制TIAM1表达，而TIAM1过表达逆转了oe-ALKBH5对甲状腺癌细胞增殖和铁死亡的调节作用。此外，TIAM1在甲状腺癌中升高，TIAM1基因敲低通过调节Nrf2/HO-1轴抑制甲状腺癌细胞增殖并促进铁死亡。此外，体内实验证据还表明，ALKBH5通过降低TIAM1的m6A水平抑制甲状腺癌进展。我们的研究结果表明，ALKBH5通过m6A-TIAM1-Nrf2/HO-1轴诱导铁死亡来抑制甲状腺癌进展，提示ALKBH5可能是甲状腺癌治疗和诊断的潜在靶分子。
