Abstract：
Endometrial carcinoma (EC) is a rising concern among gynecological malignancies. Iroquois Homeobox 2 (IRX2), a member of the Iroquois homeobox gene family, demonstrates variable effects in different cancer types, emphasizing the need for extensive exploration of its involvement in EC progression. Utilizing TCGA and GEO databases, as well as performing immunohistochemistry (IHC) analysis on clinical samples, we assessed the expression levels of IRX2 and its promoter methylation in EC. To understand the functional roles of IRX2, we conducted various assays including in vitro CCK-8 assays, colony formation assays, cell invasion assays, and cell apoptosis assays. Moreover, we utilized in vivo subcutaneous xenograft mouse models. Additionally, we performed KEGG pathway and gene set enrichment analyses to gain insights into the underlying mechanisms. To validate the regulatory relationship between IRX2 and RUVBL1, we employed chromatin immunoprecipitation and luciferase reporter assays. Our results indicate significantly reduced levels of IRX2 expression in EC, correlating with higher histological grades, advanced clinical stages, and diminished overall survival. We observed that DNA methylation of the IRX2 promoter suppresses its expression in EC, with cg26333652 and cg11793269 playing critical roles as methylated sites. In contrast, ectopic overexpression of IRX2 substantially inhibits cell proliferation and invasion, and promotes cell apoptosis. Additionally, we discovered that IRX2 exerts negative regulation on the expression of RUVBL1, which is upregulated in EC and associated with a poorer prognosis. In conclusion, our findings indicate that decreased expression of IRX2 facilitates EC cell growth through the regulation of RUVBL1 expression, thereby contributing to the development of EC. Hence, targeting the IRX2-RUVBL1 axis holds promise as a potential therapeutic strategy for EC treatment.
摘要：
子宫内膜癌（EC）是妇科恶性肿瘤中日益关注的问题。易洛魁Homeobox2(IRX2)，易洛魁异型盒基因家族的一员,在不同类型的癌症中表现出不同的效果，强调需要广泛探索其参与欧共体进程。利用TCGA和GEO数据库，以及对临床样本进行免疫组织化学（IHC）分析，我们评估了IRX2及其启动子甲基化在EC中的表达水平.为了了解IRX2的功能作用，我们进行了各种测定，包括体外CCK-8测定，集落形成试验,细胞侵袭试验，和细胞凋亡测定。此外，我们使用了体内皮下异种移植小鼠模型。此外,我们进行了KEGG通路和基因集富集分析,以深入了解其潜在机制.为了验证IRX2和RUVBL1之间的调节关系，我们采用了染色质免疫沉淀和荧光素酶报告基因测定。我们的结果表明，在EC中IRX2表达水平显着降低，与较高的组织学等级相关，晚期临床阶段，总体生存率下降。我们观察到IRX2启动子的DNA甲基化抑制其在EC中的表达，cg26333652和cg11793269作为甲基化位点起关键作用。相比之下,IRX2的异位过表达显著抑制细胞增殖和侵袭，促进细胞凋亡。此外,我们发现IRX2对RUVBL1的表达有负调控作用,RUVBL1在EC中上调,与预后较差有关。总之,我们的发现表明，IRX2的表达降低通过调节RUVBL1的表达促进EC细胞的生长，从而促进EC的发展。因此，靶向IRX2-RUVBL1轴有望成为EC治疗的潜在治疗策略.
