Department of Obstetrics and Gynecology, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, China; Key Laboratory of Birth Defects and Related Diseases of Women and Children Sichuan University, Ministry of Education, Chengdu, Sichuan, China.
Department of Obstetrics and Gynecology, West China Second University Hospital, Sichuan University, Chengdu, Sichuan, China; Key Laboratory of Birth Defects and Related Diseases of Women and Children Sichuan University, Ministry of Education, Chengdu, Sichuan, China.
J Biol Chem. 2024 Sep;300(9):107680. doi: 10.1016/j.jbc.2024.107680. Epub 2024 Aug 17.
Endometrial cancer (EC) is the most prevalent gynecological epithelial malignancy. DNA methylation is a promising cancer biomarker but limited use for detecting EC. We previously found that the level of cysteine dioxygenase 1 (CDO1) promoter methylation was elevated in EC patients through methylomics, but the role and mechanism of CDO1 in EC remained unclear. Here, the methylation level of CDO1 promoter was detected by bisulfite-sequencing PCR and methylation-specific PCR (bisulfite conversion-based PCR methods, which remain the most commonly used techniques for methylation detection). Cells were incubated with erastin (the ferroptosis activator). Cell vitality was measured using the cell counting kit-8 assay. FAM83H-AS1 cellular distribution was analyzed by the fluorescence in situ hybridization assay. Lipid reactive oxygen species level was examined by BODIPY-C11 staining. The interactions between FAM83H-AS1, CDO1, and DNA methyltransferase1 (DNMT1) were analyzed by RNA-binding protein immunoprecipitation or chromatin immunoprecipitation assay. The xenograft mouse model was utilized to test CDO1 and FAM83H-AS1's influence on tumor development in vivo. Results showed that CDO1 was hypermethylated and downregulated in EC. CDO1 knockdown reduced erastin-induced ferroptosis in EC cells. Mechanistically, DNMT1 is a DNA methyltransferase, which can transfer methyl groups to cytosine nucleotides in genomic DNA. Long noncoding RNA FAM83H-AS1 increased CDO1 promoter methylation level and inhibited its expression in EC cells by recruiting DNMT1. CDO1 knockdown or FAM83H-AS1 overexpression promoted EC tumor growth in vivo. Long noncoding RNA FAM83H-AS1 inhibited ferroptosis in EC by recruiting DNMT1 to increase CDO1 promoter methylation level and inhibit its expression.
子宫内膜癌（EC）是最常见的妇科上皮恶性肿瘤。DNA 甲基化是一种很有前途的癌症生物标志物，但在检测 EC 方面的应用有限。我们之前通过甲基组学发现 EC 患者胱氨酸双加氧酶 1（CDO1）启动子甲基化水平升高，但 CDO1 在 EC 中的作用和机制仍不清楚。本研究采用亚硫酸氢盐测序 PCR 和甲基化特异性 PCR（基于亚硫酸氢盐转化的 PCR 方法，仍然是最常用的甲基化检测技术）检测 CDO1 启动子的甲基化水平。用 erastin（铁死亡激活剂）孵育细胞。用细胞计数试剂盒-8 检测细胞活力。用荧光原位杂交检测 FAM83H-AS1 细胞分布。用 BODIPY-C11 染色检测脂质活性氧水平。用 RNA 结合蛋白免疫沉淀或染色质免疫沉淀检测 FAM83H-AS1、CDO1 和 DNA 甲基转移酶 1（DNMT1）之间的相互作用。利用异种移植小鼠模型检测 CDO1 和 FAM83H-AS1 在体内对肿瘤发展的影响。结果表明，CDO1 在 EC 中呈高甲基化和下调。CDO1 敲低减少了 EC 细胞中 erastin 诱导的铁死亡。机制上，DNMT1 是一种 DNA 甲基转移酶，可将甲基基团转移到基因组 DNA 中的胞嘧啶核苷酸上。长链非编码 RNA FAM83H-AS1 通过招募 DNMT1 增加 CDO1 启动子甲基化水平并抑制其在 EC 细胞中的表达，从而增加 CDO1 启动子甲基化水平并抑制其表达。CDO1 敲低或 FAM83H-AS1 过表达促进了 EC 肿瘤在体内的生长。长链非编码 RNA FAM83H-AS1 通过招募 DNMT1 抑制 EC 中的铁死亡，从而增加 CDO1 启动子甲基化水平并抑制其表达。
