Enhancer of zeste homolog 2 (EZH2) is a member of the polycomb protein family and an oncogene that is overexpressed in various human cancers. Here, researchers used immunohistochemical staining to find that EZH2 expression levels are associated with poor prognosis in oral squamous cell carcinoma (OSCC) patients. EZH2 overexpression significantly promoted glycolysis, epithelial-mesenchymal transition (EMT), migration, and invasion in OSCC cells. Conversely, EZH2 silencing inhibited glycolysis, EMT, migration, and invasion in OSCC cells. Ectopic overexpression of EZH2 increased STAT3 phosphorylation at pY705 and decreased FoxO1 expression; while inhibiting STAT3 enhanced FoxO1 expression. Furthermore, in a nude mouse xenograft model, EZH2 overexpression led to a significant decrease in FoxO1 mRNA levels. These results suggest that targeting EZH2 may be a potential therapeutic target for OSCC.
To investigate the role of EZH2 in oral squamous cell carcinoma (OSCC) cell migration, invasion, and epithelial-mesenchymal transition (EMT), researchers constructed EZH2 knockdown Cal-27 and Tca8113 cell lines, and confirmed the knockdown effect using Western blot and RT-PCR (Figure 1A). Wound healing assays showed that the cell migration area was reduced by 31.9% and 23% in EZH2 knockdown Cal-27 and Tca8113 cells, respectively (Figure 1B). Compared with the control group, the invasion ability of EZH2 knockdown Cal-27 and Tca8113 cells was reduced by 34.9% and 24%, respectively (Figure 1C). Subsequently, researchers detected EMT-related markers using Western blot and RT-PCR. The results showed that in EZH2 knockdown Cal-27 cells, the protein and mRNA levels of epithelial markers E-cadherin and β-catenin were significantly increased, while the protein and mRNA levels of mesenchymal markers N-cadherin and vimentin were significantly decreased (Figure 1D), which was also confirmed by immunofluorescence staining (Figure 1E). However, no significant difference in apoptosis was detected between the EZH2 knockdown group and the control group (Figure 1F).
Figure 1. EZH2 knockdown inhibits migration, invasion potential and EMT in OSCC cells. (Zheng M, et al., 2019)