ZEB1 promotes invasion and metastasis of endometrial cancer by interacting with HDGF and inducing its transcription.

Zinc finger E-box binding homeobox 1 (ZEB1), as a typical transcription inhibitory factor of E-cadherin, plays a major role in stimulating the invasion and metastasis of tumors via modulating the epithelial-mesenchymal transition (EMT) signal. However, its function and modulatory mechanisms in endometrial carcinoma (EC) remain unclear. In this study, silencing ZEB1 significantly reduced EC cell migration, invasion, and metastasis, as well as enhanced the sensitivity of EC cells to cisplatin (cDDP) in vitro and in vivo. Mechanism analysis indicated that ZEB1 interacts with hepatoma-derived growth factor (HDGF) and co-localizes in the nucleus. In addition, ZEB1 as a transcription factor binds to the promoter of HDGF to stimulate HDGF transcription. Furthermore, suppression of HDGF in ZEB1-overexpressed EC cells not only reduced the expression of ß-catenin, TCF4, and ZEB1, but also repressed ß-catenin translocation from the cytoplasm into the nucleus and further downregulated the combination with TCF4. Interestingly, the ß-catenin/TCF4 signaling feedback stimulates ZEB1 transcription and therefore constitutes a positive feedback loop. In clinical samples, ZEB1 positively correlates with HDGF expression, and co-expression of ZEB1 and HDGF promotes the pathogenesis of EC. In summary, our study demonstrated that the positive feedback loop of ZEB1/HDGF/ß-catenin/TCF4 plays an unfavorable role in the metastasis of endometrial carcinoma.

[Expression of phosphoglycerate kinase 1 in endometrial carcinoma and its association with patients' outcome].

OBJECTIVE: To investigate the expression of phosphoglycerate kinase 1 (PGK1) and its prognostic value in endometrial carcinoma (EC). METHODS: The expression of PGK1 was detected immunohistochemically in 30 normal endometrium and 130 EC specimens. The relationship between PGK1 protein expression and the clinicopathological features of the patients was evaluated. RESULTS: Immunohistochemical analysis revealed low PGK1 expression in 55.4% (72/130) and high PGK1 expression in 44.6% (58/130) of the EC specimens, as compared with the rates of 90% (27/30) and 10% (3/30) in normal endometrium, respectively (P<0.001). PGK1 expression was significantly correlated with FIGO stage (P<0.001), histological grade (P=0.002) and lymph node metastasis (P<0.001). Kaplan-Meier survival analysis indicated that patients with a high PGK1 expression had a shorter overall survival rate than those with a low PGK1 expression (P<0.001). Multivariate analysis showed that a high PGK1 expression was not the independent predictor of the prognosis of EC (P=0.077). CONCLUSION: A high expression of PGK1 is associated with aggressive and metastatic behaviors of EC, and detection of PGK1 provides assistance in evaluating the prognosis of patients with EC.