G9a抑制剂BIX-01294对脑胶质瘤U251细胞株作用机制的研究

发布时间：2018-05-09 08:44

本文选题：G9a + 脑胶质瘤　；参考：《福建医科大学》2014年硕士论文

【摘要】：【目的】：研究组蛋白甲基化酶G9a、组蛋白H3K9me2、组蛋白H3K9me1在人类脑胶质瘤组织和癌旁组织中表达的差异及临床意义。观察甲基化酶G9a抑制剂BIX-01294在体外人类脑胶质瘤U251细胞株增殖、凋亡的改变、组蛋白H3K9、H3K27甲基化及组蛋白H3乙酰化水平的影响，初步探讨其机制。【方法】：1、免疫组织化学方法检测人类脑胶质瘤组织和癌旁组织中组蛋白甲基化酶G9a、组蛋白H3K9me2、组蛋白H3K9me1蛋白的表达差异，统计学分析探讨其临床意义。2、 MTS法绘制BIX-01294作用人类脑胶质瘤U251细胞后的生长曲线，TUNEL法检测U251细胞调亡率的变化。3、Western blot法检测GX-01294作用人类脑胶质瘤U251细胞后凋亡相关蛋白BCL-2、Bax、Caspase-9、Caspase-3；组蛋白H3K9me、H3K9me2、H3K9me3、组蛋白H3K27me1、组蛋白H3K27me2、组蛋白H3乙酰化状态的影响。【结果】：1、在脑胶质瘤的癌组织中组蛋白甲基转移酶G9a蛋白的阳性率为86%（43/50），癌旁组织中阳性率为42%（21/50），，p0.01，有统计学意义；癌组织中组蛋白H3K9me2的阳性率为82%（41/50），癌旁组织中阳性率为38%（19/50），确切概率法检验，χ2=18.38，p0.01；组蛋白甲基转移酶G9a蛋白和组蛋白H3K9me2的表达与脑胶质瘤WHO分级相关；脑胶质瘤的癌组织中组蛋白H3K9me的阳性率为54%（27/50），癌旁组织中阳性率为44%（22/50），确切概率法检验，χ2=1.21，p＞0.05，无统计学意义。2、BIX-01294抑制人类脑胶质瘤U251细胞增殖；下调BCL-2，上调Bax、 caspase-3、caspase-9，诱导细胞凋亡。3、 BIX-01294下调组蛋白H3K9me1、H3K9me2及组蛋白H3K27me1、组蛋白H3K27me2水平，而对组蛋白H3K9me3及组蛋白H3乙酰化无影响。【结论】：1、脑胶质瘤癌组织中组蛋白甲基化酶G9a、H3K9me2高表达，与脑胶质瘤WHO分级相关，提示G9a、H3K9me2可能有促进胶质瘤的发生、发展作用。2、BIX-01294可以抑制脑胶质瘤细胞增殖，启动凋亡程序、诱导肿瘤细胞凋亡，进一步研究发现组蛋白H3K9、H3K27甲基化改变导致染色体构象改变可能是其机制， BIX-01294可能成为治疗脑胶质瘤的潜在新药。
[Abstract]:[objective]: to study the difference of expression of protein methylase G9a, histone H3K9me2 and histone H3K9me1 in human glioma and paracancerous tissues and its clinical significance. To observe the effect of methylase G9a inhibitor BIX-01294 on the proliferation and apoptosis of human glioma cell line U251 in vitro, the effect of histone H3K9, H3K27 methylation and histone H3 acetylation, and to explore its mechanism. [methods] the expression of histone methylase G9a, histone H3K9me2 and histone H3K9me1 protein in human glioma and paracancerous tissues were detected by immunohistochemistry. The clinical significance of U251 cells was studied by statistical analysis. The growth curve of U251 cells induced by BIX-01294 was plotted by MTS method. Tunel method was used to detect the apoptosis rate of U251 cells after U251 cells were treated with GX-01294. The apoptosis related to U251 cells induced by GX-01294 was detected by Western blot. The effects of histone H3K9me2, histone H3K27me1, histone H3K27me2, histone H3 acetylation state. [results] the positive rate of histone methyltransferase G9a protein in glioma tissues was 8643 / 50, and the positive rate in adjacent tissues was 42%. The positive rate of histone H3K9me2 in cancer tissues was 82 / 41 / 50 and 38 / 38 / 50 in adjacent tissues. The positive rate of histone H3K9me2 and histone H3K9me2 were correlated with the WHO grade of gliomas by 蠂 2 + 18.38% p0.01.The expression of histone methyltransferase G9a and histone H3K9me2 were correlated with the WHO grade of gliomas. The positive rate of histone H3K9me in glioma tissues was 54 / 27 / 50 and that in adjacent tissues was 44 / 22 / 50. The exact probability test showed that 蠂 2 + 1. 21% p > 0. 05. There was no statistical significance. 2BIX-01294 inhibited the proliferation of human glioma U251 cells. Down-regulation of BCL-2, up-regulation of Bax, caspase-3 and caspase-9, induction of apoptosis. BIX-01294 down-regulated the levels of histone H3K9me2 and histone H3K27me1, histone H3K27me2, but had no effect on histone H3K9me3 and histone H3 acetylation. [conclusion] the high expression of histone methylase G9aOH3K9me2 in glioma tissues is related to the WHO grading of gliomas, suggesting that G9aH3K9me2 may promote the development of glioma, and the developmental action of .2BIX-01294 can inhibit the proliferation of glioma cells and initiate the process of apoptosis. Apoptosis of tumor cells was induced by histone H3K9 and H3K27 methylation, which may be the mechanism of chromosome conformation change. BIX-01294 may be a potential new drug in the treatment of glioma.
【学位授予单位】：福建医科大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：R739.4

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