Promoter methylation level affects the expression of E-cadherin in salivary malignant pleomorphic adenoma cell lines

Abstract

Abstract: PURPOSE: To investigate the effect of promoter methylation on the expression of E-cadherin by changing the E-cadherin gene promoter methylation level in human salivary malignant pleomorphic adenoma cell lines in vitro. METHODS: After appropriate concentrations of 5-Aza-CdR and TGF-β1 treatment, E-cadherin promoter methylation, protein and mRNA expression were detected by bisulfite sequencing, Western blotting, fluorescence quantitative real-time PCR respectively. Wound-healing test and Transwell test were used to identify the corresponding changes of SM-AP4 and SM-AP1 cells when E-cadherin expression was altered. SPSS 13.0 software package was used for statistical analysis. RESULTS: After treatment with 5-Aza-CdR, E-cadherin promoter methylation rate was decreased significantly in SM-AP4 cell (P<0.001). E-cadherin protein and mRNA expression was significantly elevated (P<0.05) and the corresponding ability of cell migration significantly decreased (P<0.05). After TGF-β1 treatment in SM-AP1, vimentin expression was induced. E-cadherin promoter methylation rate significantly increased (P<0.001) and E-cadherin protein and mRNA expression significantly decreased (P<0.05). The corresponding migration ability of SM-AP1 cell significantly increased (P<0.05). CONCLUSIONS: DNA methylation is an important mechanism to regulate the expression of E-cadherin in MPA, which can improve the level of E-cadherin protein expression and decrease the ability of tumor metastasis by reducing the methylation level of E-cadherin gene promoter.

Key words: E-cadherin, 5-Aza-CdR, TGF-β1, DNA methylation, Malignant pleomorphic adenoma, Salivary gland

CLC Number:

R739.8

XIA Liang, ZHANG Chun-ye, HU Yu-hua, QIAN Jia-jun, LI Jiang, TIAN Zhen. Promoter methylation level affects the expression of E-cadherin in salivary malignant pleomorphic adenoma cell lines[J]. China Journal of Oral and Maxillofacial Surgery, 2016, 14(4): 308-314.

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