DEK在肺癌細(xì)胞中的表達(dá)水平及其作用機理的研究
發(fā)布時間:2018-10-16 14:27
【摘要】:工作目的:DEK是一種在多細(xì)胞生物與部分單細(xì)胞生物中廣泛表達(dá)的癌蛋白,在大多數(shù)惡性腫瘤中高表達(dá),而在終末分化的細(xì)胞中保持低表達(dá)水平。DEK可通過改變?nèi)旧|(zhì)結(jié)構(gòu),修復(fù)DNA,參與mRNA剪接與信號通路,或作為轉(zhuǎn)錄因子等途徑調(diào)控細(xì)胞的增殖、分化、凋亡、遷移、衰老等,與腫瘤細(xì)胞的形成有著重要的關(guān)系。然而關(guān)于DEK在肺腫瘤組織中的表達(dá)情況及其作用機理尚未有完善的研究成果。本研究將對肺癌細(xì)胞中DEK的表達(dá)量、作用、分子機制與轉(zhuǎn)錄調(diào)控進行檢測與探究,深化對DEK與腫瘤形成之間關(guān)系的了解。 研究方法:本實驗通過逆轉(zhuǎn)錄PCR (RT-PCR)與免疫組織化學(xué)實驗(IHC)檢測肺癌患者組織中DEK表達(dá)水平差異。并通過使用siRNA與DEK過表達(dá)載體轉(zhuǎn)染A549肺腺癌細(xì)胞,檢測DEK沉默與過表達(dá)的細(xì)胞功能與相關(guān)基因表達(dá)水平的改變。其中通過MTT法與集落形成法檢測DEK表達(dá)水平與細(xì)胞增殖能力之間的關(guān)系,Annexin V-PE細(xì)胞凋亡檢測試劑盒檢測DEK表達(dá)水平與細(xì)胞凋亡的關(guān)系、Matrigel細(xì)胞侵襲實驗檢測DEK表達(dá)水平與細(xì)胞侵襲能力之間的關(guān)系。此外,通過對肺癌患者基因組DNA進行DEK啟動子區(qū)域的BSP實驗,檢測其甲基化水平的差異,探究DEK啟動子區(qū)域甲基化水平與其轉(zhuǎn)錄調(diào)控的關(guān)系。 成果和結(jié)論:通過RT-PCR實驗發(fā)現(xiàn),相對于肺正常組織,DEK mRNA在51.7%的肺腫瘤組織中發(fā)生高表達(dá);其中有87.5%的肺腺癌組織發(fā)生DEK mRNA的高表達(dá),高于其他組織學(xué)類型。而通過IHC實驗發(fā)現(xiàn),肺腫瘤組織中,81.5%表現(xiàn)出DEK蛋白的陽性表達(dá),39.5%表現(xiàn)出DEK蛋白的強陽性表達(dá),強陽性率高于正常組織。進一步,通過使用siRNA與DEK過表達(dá)載體轉(zhuǎn)染A549肺腺癌細(xì)胞系,改變DEK表達(dá)量,檢測得到肺癌細(xì)胞DEK表達(dá)水平與細(xì)胞增殖能力和侵襲能力有著正相關(guān)關(guān)系,而與細(xì)胞凋亡率有著負(fù)相關(guān)關(guān)系,且p53、p65、ATM三種與DEK功能相關(guān)的基因表達(dá)量均與DEK的表達(dá)水平呈負(fù)相關(guān)關(guān)系。實驗同時發(fā)現(xiàn),在肺腫瘤組織中,DEK啟動子區(qū)域CpG島的總甲基化水平與E2F和YY1等轉(zhuǎn)錄因子結(jié)合位點CpG的甲基化水平均有所下降。以上結(jié)果顯示,DEK在肺癌中的高表達(dá)與其作為癌基因的功能密切相關(guān),其作用涉及p53、p65、ATM等DEK相關(guān)基因的作用,同時還提示DEK啟動子區(qū)域去甲基化與其轉(zhuǎn)錄活化及腫瘤形成之間的關(guān)系。
[Abstract]:Objective: DEK is a kind of oncoprotein widely expressed in multicellular organisms and some unicellular organisms. It is highly expressed in most malignant tumors and remains low in terminal differentiated cells. DEK can change chromatin structure. Repair DNA, is involved in mRNA splicing and signaling pathway, or as a transcription factor to regulate cell proliferation, differentiation, apoptosis, migration, aging, and has an important relationship with tumor cell formation. However, the expression and mechanism of DEK in lung neoplasms have not been well studied. In this study, the expression, role, molecular mechanism and transcriptional regulation of DEK in lung cancer cells were examined and explored to deepen the understanding of the relationship between DEK and tumor formation. Methods: reverse transcription PCR (RT-PCR) and immunohistochemical (IHC) were used to detect the expression of DEK in lung cancer. SiRNA and DEK overexpression vectors were used to transfect A549 lung adenocarcinoma cells to detect the changes of DEK silencing and overexpression cell function and the expression level of related genes. Among them, the relationship between DEK expression and cell proliferation was detected by MTT and colony forming assay, Annexin V-PE cell apoptosis detection kit was used to detect the relationship between DEK expression and cell apoptosis, and Matrigel cell invasion assay was used to detect DEK expression water. The relationship between flatness and cell invasiveness. In addition, the difference of methylation level in genomic DNA of lung cancer patients was detected by BSP test of DEK promoter region, and the relationship between methylation level of DEK promoter region and its transcriptional regulation was explored. Results and conclusions: compared with normal lung tissues, the expression of, DEK mRNA was higher in 51.7% of lung tumor tissues, and 87.5% of lung adenocarcinoma tissues had higher expression of DEK mRNA than other histological types. IHC assay showed that 81.5% of lung tumors showed positive expression of DEK protein, 39.5% showed strong positive expression of DEK protein, and the strong positive rate was higher than that of normal tissue. Furthermore, by using siRNA and DEK overexpression vector to transfect A549 lung adenocarcinoma cell line, the expression of DEK was changed, and the expression level of DEK in lung cancer cell line was positively correlated with cell proliferation and invasion ability. However, there was a negative correlation between the expression of p53 and p65ATM genes related to DEK function and the level of DEK expression. It was also found that the total methylation level of CpG island in the DEK promoter region and the CpG methylation level of transcription factor binding sites such as E2F and YY1 decreased in lung tumor tissues. These results suggest that the high expression of DEK in lung cancer is closely related to its function as a oncogene, and its role is related to the role of DEK related genes such as p53, p65, ATM, and so on. The relationship between demethylation of DEK promoter region and its transcriptional activation and tumor formation was also suggested.
【學(xué)位授予單位】:北京交通大學(xué)
【學(xué)位級別】:碩士
【學(xué)位授予年份】:2015
【分類號】:R734.2
本文編號:2274654
[Abstract]:Objective: DEK is a kind of oncoprotein widely expressed in multicellular organisms and some unicellular organisms. It is highly expressed in most malignant tumors and remains low in terminal differentiated cells. DEK can change chromatin structure. Repair DNA, is involved in mRNA splicing and signaling pathway, or as a transcription factor to regulate cell proliferation, differentiation, apoptosis, migration, aging, and has an important relationship with tumor cell formation. However, the expression and mechanism of DEK in lung neoplasms have not been well studied. In this study, the expression, role, molecular mechanism and transcriptional regulation of DEK in lung cancer cells were examined and explored to deepen the understanding of the relationship between DEK and tumor formation. Methods: reverse transcription PCR (RT-PCR) and immunohistochemical (IHC) were used to detect the expression of DEK in lung cancer. SiRNA and DEK overexpression vectors were used to transfect A549 lung adenocarcinoma cells to detect the changes of DEK silencing and overexpression cell function and the expression level of related genes. Among them, the relationship between DEK expression and cell proliferation was detected by MTT and colony forming assay, Annexin V-PE cell apoptosis detection kit was used to detect the relationship between DEK expression and cell apoptosis, and Matrigel cell invasion assay was used to detect DEK expression water. The relationship between flatness and cell invasiveness. In addition, the difference of methylation level in genomic DNA of lung cancer patients was detected by BSP test of DEK promoter region, and the relationship between methylation level of DEK promoter region and its transcriptional regulation was explored. Results and conclusions: compared with normal lung tissues, the expression of, DEK mRNA was higher in 51.7% of lung tumor tissues, and 87.5% of lung adenocarcinoma tissues had higher expression of DEK mRNA than other histological types. IHC assay showed that 81.5% of lung tumors showed positive expression of DEK protein, 39.5% showed strong positive expression of DEK protein, and the strong positive rate was higher than that of normal tissue. Furthermore, by using siRNA and DEK overexpression vector to transfect A549 lung adenocarcinoma cell line, the expression of DEK was changed, and the expression level of DEK in lung cancer cell line was positively correlated with cell proliferation and invasion ability. However, there was a negative correlation between the expression of p53 and p65ATM genes related to DEK function and the level of DEK expression. It was also found that the total methylation level of CpG island in the DEK promoter region and the CpG methylation level of transcription factor binding sites such as E2F and YY1 decreased in lung tumor tissues. These results suggest that the high expression of DEK in lung cancer is closely related to its function as a oncogene, and its role is related to the role of DEK related genes such as p53, p65, ATM, and so on. The relationship between demethylation of DEK promoter region and its transcriptional activation and tumor formation was also suggested.
【學(xué)位授予單位】:北京交通大學(xué)
【學(xué)位級別】:碩士
【學(xué)位授予年份】:2015
【分類號】:R734.2
【參考文獻(xiàn)】
相關(guān)期刊論文 前1條
1 王璇;黃紹輝;於麗喬;劉潔;刁堯;孫長伏;;DEK原癌基因與口腔鱗狀細(xì)胞癌的關(guān)系[J];上?谇会t(yī)學(xué);2014年01期
,本文編號:2274654
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