The Effect And Expression Of H3K4me3 In Middle Ear Cholesteatoma

Part ? Expression of histone H3K4me3 in middle ear cholesteatomaOBJECTIVE: To quantify the expression of histone H3 lysine 4 trimethylation(H3K4me3)in middle ear cholesteatoma and outer ear canal epithelial tissues in order to study its significance in the development and progression of middle ear cholesteatoma.METHODS: Thirty patients with middle ear cholesteatoma admitted to the Department of Otolaryngology Head and Neck Surgery from September 2017 to June 2018 were enrolled.The cholesteatoma matrix of the middle ear was used as the study group.The external auditory canal tissue of the same patient was used as the control group.The expression level of H3K4me3 was analyzed by Western blot.After Western blotting,the results were confirmed by immunohistochemical staining,and H3K4me3 was located in study group and control group.Results: 1.The results of western blotting showed that the expression level of histone H3K4me3 in cholesteatoma matrix was significantly lower than that in external auditory canal tissue.The difference was statistically significant.2.Immunohistochemical staining showed that H3K4me3 was expressed in cholesteat epithelial tissues and epithelial tissues of external auditory canal,localized in the nucleus of cholesteatoma and epithelial tissues of external auditory canal,which showed brown granules in the nucleus of epithelial tissue.The expression of histone H3K4me3 in cholesteatoma maternal tissue was significantly lower than that in external auditory canal tissue,and the difference was statistically significant.Conclusion: The expression of histone H3K4me3 is down-regulated in the epithelial tissues of middle ear cholesteatoma,which may be involved in the development and progression of middle ear cholesteatoma,and it may become a new target for the treatment of middle ear cholesteatoma.Part ? Expression of histone H3K4me3 methylase and demethylase in middle ear cholesteatomaOBJECTIVE: To screen for major factors affecting the expression of H3K4me3 in epithelial tissues of middle ear cholesteatoma.METHODS: Thirteen patients with middle ear cholesteatoma admitted to the Department of Otorhinolaryngology Head and Neck Surgery from September 2017 to June 2018 were enrolled.The cholesteatoma matrix of the middle ear was used as the study group.The external auditory canal tissue of the same patient was used as the control group.The JARID1 family(JARID1A,JARID1 B,JARID1C,JARID1D),MLL family(MLL1,MLL2,MLL3,MLL4,SETD1A/B),MLL5 and SET7/9 were detected by RT-qPCR.The mRNA expression levels of each gene were analyzed by relative quantitative analysis to screen out possible factors affecting the difference in H3K4me3 expression.RESULTS: The results of RT-qPCR showed that the expression of H3K4me3 specific methyltransferase MLL family genes decreased in the middle ear cholesteatoma,including MLL1,MLL2.MLL5 and SETD1A;and their specific demethylases were not significantly different in the expression of middle ear cholesteatoma.Conclusion: The down-regulation of H3K4me3 in middle ear cholesteatoma may be the result of a combination of multiple specific methyltransferases such as MLL1,MLL2,MLL5 and SETD1 A.