EXT1 and Its Methylation Involved in the Progression of Uterine Corpus Endometrial Carcinoma Pathogenesis

Uterine corpus endometrial carcinoma (UCEC) is one of the most common gynecologic tumors. Due to the high recurrence and metastasis of UCEC, it is crucial for patients to find new biomarkers for diagnosis and therapy. In this study, R software and the TCGA database were used to screen candidate UCEC predictive markers. Western blot and RT-qPCR were performed to detect protein and mRNA expression of EXT1 in UCEC cell lines. In addition, MTT assay, flow cytometry, transwell assay, and wound healing assay were conducted to assess the cell viability, apoptosis, invasion, and migration in UCEC cells. Overlap-extension PCR technique was employed to construct the vector targeting the deletion of the methylated segment of EXT1. The results showed that a total of 11 candidate genes were obtained and EXT1 was identified as a potential target. The expression and methylation levels of EXT1 were both increased in UCEC tissues and cell lines, as well as elevated EXT1 was closely related to the poor prognosis of patients. Besides, the knockdown of EXT1 significantly inhibited the malignant biological behaviors in UCEC cells. Additionally, the current study also found that the deletion of 1559-2146 bp CpG island segment upregulated EXT1 expression and promoted malignant biological behaviors in UCEC cells. Furthermore, the presence of m7G RNA methylation in UCEC cells also was found. In conclusion, the methylation of EXT1 influenced the gene expression, thereby affecting the malignant biological behaviors in UCEC cells and regulating the pathological progression of UCEC.