【摘要】：ErbB2是原癌基因erbB-2編碼的185kDa的細(xì)胞膜受體,為表皮生長因子受體(epidermal growth factor receptor,EGFR)家族成員之一。該家族包括ErbB-1(又稱EGFR,HER1)、ErbB2(又稱HER2)、ErbB-3(HER3)和ErbB-4(HER4)四個(gè)成員。ErbB2高表達(dá)腫瘤細(xì)胞中Ras-MAPK和PI3K-Akt信號(hào)傳導(dǎo)活性較高,細(xì)胞增殖能力較強(qiáng),分化成熟和凋亡機(jī)制受到抑制,細(xì)胞惡性程度高。ErbB2高表達(dá)腫瘤細(xì)胞可抵抗TNF-α、射線以及各種化療藥物引起的細(xì)胞凋亡效應(yīng)。臨床上ErbB2表達(dá)與患者預(yù)后密切相關(guān),ErbB2高表達(dá)的患者易發(fā)生腫瘤轉(zhuǎn)移,存活期短。由于ErbB2在正常細(xì)胞和腫瘤細(xì)胞中的表達(dá)水平具有顯著的差異,因而已成為腫瘤免疫生物治療的理想靶點(diǎn),亦是目前腫瘤治療研究領(lǐng)域的熱點(diǎn)分子。Herstatin是近年來發(fā)現(xiàn)的唯一天然存在的ErbB2自身抑制分子,它是ErbB2mRNA加工過程中選擇性剪接的產(chǎn)物,是一種可溶性的ErbB2受體。Herstatin能與細(xì)胞表面的ErbB2受體高親和力結(jié)合,阻礙ErbB2同源或異源二聚體的形成,抑制受體酪氨酸磷酸化及ErbB2過表達(dá)細(xì)胞的增殖能力。但是,Herstatin與ErbB2相互作用的機(jī)制及與ErbB2受體分子的結(jié)合位點(diǎn)以及抑制ErbB2過表達(dá)細(xì)胞增殖的機(jī)制均不清楚。闡明ErbB2分子表達(dá)的自身調(diào)節(jié)機(jī)制,有助于理解該受體分子在生理?xiàng)l件下表達(dá)平衡對(duì)于細(xì)胞正常分化的重要意義,而且可能為ErbB2過表達(dá)腫瘤的治療提供新思路。對(duì)二者相互作用位點(diǎn)的分析亦可為尋找到控制ErbB2的敏感靶位及有效的小分子抑制劑的設(shè)計(jì)提供依據(jù)。 本研究采用基因工程技術(shù)構(gòu)建了Herstatin的真核表達(dá)載體,將構(gòu)建成功的載體轉(zhuǎn)染ErbB2表達(dá)水平不同的細(xì)胞,在mRNA和蛋白水平均檢測(cè)到Herstatin的表達(dá)。應(yīng)用MTT法證實(shí)了Herstatin對(duì)細(xì)胞的增殖具有明顯的抑制作用。Hoechst和PI染色發(fā)現(xiàn)Herstatin轉(zhuǎn)染后可誘導(dǎo)轉(zhuǎn)染細(xì)胞凋亡,這可能是其抑制細(xì)胞增殖
[Abstract]:ErbB2 is a cell membrane receptor of 185kDa encoded by proto-oncogene erbB-2 and is a member of the (epidermal growth factor receptor,EGFR family. The family includes four members: ErbB-1 (also known as EGFR,HER1), ErbB2 (also known as HER2), ErbB-3 (HER3) and ErbB-4 (HER4). ErbB2 highly expressed tumor cells have high Ras-MAPK and PI3K-Akt signal transduction activity, strong cell proliferation ability, inhibition of differentiation, maturation and apoptosis, and high degree of malignancy. ErbB2 high expression tumor cells can resist TNF- 偽, radiation and apoptosis induced by various chemotherapeutic drugs. The expression of ErbB2 is closely related to the prognosis of patients. Patients with high expression of ErbB2 are prone to tumor metastasis and have a short survival period. Because the expression level of ErbB2 in normal cells and tumor cells is significantly different, it has become an ideal target of tumor immunobiotherapy and a hot molecule in the field of tumor therapy at present. Herstatin is the only natural self-inhibitory molecule of ErbB2 discovered in recent years, and it is the product of selective splicing in the process of ErbB2mRNA processing. It is a soluble ErbB2 receptor. Herstatin can bind to ErbB2 receptor on cell surface with high affinity, hinder the formation of ErbB2 homologous or heterodimer, and inhibit the phosphorylation of receptor tyrosine and the proliferation of ErbB2 overexpression cells. However, the mechanism of the interaction between Herstatin and ErbB2, the binding site of ErbB2 receptor molecule and the mechanism of inhibiting the proliferation of ErbB2 overexpression cells are not clear. To elucidate the self-regulation mechanism of ErbB2 molecule expression is helpful to understand the significance of the expression balance of ErbB2 molecule in the normal differentiation of cells under physiological conditions, and may provide a new idea for the treatment of ErbB2 overexpression tumor. The analysis of the interaction sites can also provide a basis for finding sensitive targets to control ErbB2 and the design of effective small molecular inhibitors. In this study, the eukaryotic expression vector of Herstatin was constructed by genetic engineering technique. The constructed vector was transformed into cells with different expression levels of ErbB2, and the expression of Herstatin was detected at both mRNA and protein levels. It was confirmed by MTT assay that Herstatin had obvious inhibitory effect on cell proliferation. Hoechst and PI staining showed that Herstatin could induce apoptosis of transfected cells, which may be due to its inhibition of cell proliferation.
【學(xué)位授予單位】：中國人民解放軍軍事醫(yī)學(xué)科學(xué)院
【學(xué)位級(jí)別】：博士
【學(xué)位授予年份】：2005
【分類號(hào)】：R346

【共引文獻(xiàn)】

相關(guān)碩士學(xué)位論文 前2條

1 李妞妞;Maspin蛋白和C-erbB-2蛋白在子宮內(nèi)膜樣腺癌中的表達(dá)及其臨床意義[D];吉林大學(xué);2011年

2 崔小健;Maspin和C-erbB-2基因在前列腺癌中表達(dá)及兩者相關(guān)性的初步研究[D];天津醫(yī)科大學(xué);2006年

，

本文編號(hào)：2507201