4EGI-1诱导细胞凋亡抑制鼻咽癌细胞增殖活性的分子机制研究

发布时间：2018-02-25 02:06

本文关键词： 鼻咽癌 4EGI-1 凋亡治疗　出处：《中南大学》2014年硕士论文　论文类型：学位论文

【摘要】：[目的]鼻咽癌(Nasopharyngeal Carcinoma, NPC)是中国南方地区最为常见恶性肿瘤之一。目前以放化疗为主的治疗仍不能有效的阻止鼻咽癌的复发、转移。真核细胞翻译起始因子-4E (Eukaryotic initiation factor4E, eIF4E)为帽状依赖性翻译过程中的限速因子,eIF4E/eIF4G复合物的组装在翻译起始阶段的基因表达调控中起关键性作用。这一复合物受真核翻译起始因子4E结合蛋白(4EBPs)调节,4EBPs与eIF4G竞争性地连结至eIF4E。正常细胞中,非磷酸化状态的4EBPs与eIF4E结合,限制eIF4E/eIF4G复合物的组装,从而抑制帽状依赖性翻译,影响肿瘤相关蛋白质的翻译。小分子化合物4EGI-1能干扰eIF4E/eIF4G的相互作用,有效地增加4EBP1与eIF4E结合,下调eIF4E调控的翻译起始依赖性肿瘤相关蛋白的表达,抑制肿瘤细胞生长和诱导细胞凋亡。我们前期研究发现4EGI-1具有增加DR5蛋白表达和下调c-FLIP蛋白表达,增加肿瘤坏死因子相关凋亡诱导配体(Tumor necrosis factor-related apoptosis inducing ligand, TRAIL)诱导肺癌细胞凋亡发挥抗肿瘤作用的功能。但未见4EGI-1在鼻咽癌中的研究报道。基于上述前期研究结果,我们研究4EGI-1对鼻咽癌细胞增殖活性的影响,探讨4EGI-1在鼻咽癌中作用的具体分子机制；分析DR4和DR5蛋白表达与鼻咽癌临床病理特征的相关性,为鼻咽癌的靶向治疗和分子靶标的研究提供科学依据和理论基础。[方法](1)不同浓度的4EGI-1处理鼻咽癌细胞,流式细胞学检测鼻咽癌细胞凋亡率,Western blotting检测c-PARP、Caspase-8、DR5、 HIF-1α、p-4EBP1和DR4蛋白的表达,平板克隆形成检测4EGI-1对鼻咽癌细胞的放疗增敏效果。(2)免疫组化检测DR4和DR5在鼻咽癌组织中的蛋白表达水平。[结果](1)4EGI-1诱导鼻咽癌细胞凋亡,显著抑制鼻咽癌的增殖活性；(2)4EGI-1增加鼻咽癌细胞c-PARP、 Caspase8、DR5和HIF-1α蛋白的表达,降低p-4EBP1和DR4蛋白表达；(3)4EGI-1增加2Gy和4Gy放射剂量治疗鼻咽癌细胞的疗效,增敏比为1.195；(4)临床Ⅲ-Ⅳ期鼻咽癌组织中DR5蛋白表达显著低于临床Ⅰ-Ⅱ期鼻咽癌。(5)伴有淋巴结转移的鼻咽癌组织中DR5蛋白阳性表达率低于无淋巴结转移者,鼻咽癌转移灶的DR5阳性表达也显著低于与其匹配的原发鼻咽癌。(6)多因素回归分析结果也显示DR5蛋白表达与鼻咽癌淋巴结转移状况显著相关。[结论]1、4EGI-1诱导鼻咽癌细胞凋亡抑制鼻咽癌细胞的增殖活性；4EGI-1增加放射治疗鼻咽癌细胞的疗效。2、4EGI-1促进鼻咽癌细胞过表达DR5,c-PARP和Caspase8,通过激活死亡受体通路诱导细胞凋亡发挥抗肿瘤作用。3、DR5蛋白表达降低促进鼻咽癌淋巴结转移和鼻咽癌患者的临床进展；DR5蛋白表达可作为评估鼻咽癌淋巴结转移和治疗的分子标志物。我们的研究结果为类似4EGI-1结构的抗鼻咽癌的靶向药物研究提供科学依据和理论基础。图18幅,表9个,参考文献79篇。
[Abstract]:[Objective] nasopharyngeal carcinoma (Nasopharyngeal Carcinoma NPC) is one of the most common malignant tumors in South China. Treatment at present is mainly composed of chemotherapy still can not effectively prevent the recurrence of nasopharyngeal carcinoma and metastasis. Eukaryotic translation initiation factor -4E (Eukaryotic initiation factor4E, eIF4E) is the rate limiting factor of cap dependent translation process eIF4E/eIF4G, assembly of complex gene expression in translation initiation plays a key role in the regulation of this complex by eukaryotic translation initiation factor 4E binding protein (4EBPs) regulation, 4EBPs compete with eIF4G to link to eIF4E. in normal cells, 4EBPs and eIF4E phosphorylation state with limited eIF4E/eIF4G assembly compound, inhibits cap dependent translation, influence of tumor associated protein translation. Small molecule 4EGI-1 can interfere with eIF4E/eIF4G interaction, effectively increase 4E BP1 combined with eIF4E, down-regulation of eIF4E expression regulation of translation initiation dependent tumor related protein, inhibit tumor cell growth and induce cell apoptosis. Our previous study found that 4EGI-1 can increase the expression of DR5 and down-regulation of c-FLIP protein expression, increased tumor necrosis factor related apoptosis inducing ligand (Tumor necrosis factor-related apoptosis inducing ligand, TRAIL) induced apoptosis lung cancer cells play the role of anti-tumor function. But there is no research reports of 4EGI-1 in nasopharyngeal carcinoma. The preliminary study based on the results, we study the effect of 4EGI-1 on nasopharyngeal carcinoma cell proliferation activity, to explore the molecular mechanism of action of 4EGI-1 in nasopharyngeal carcinoma; analysis of DR4 and DR5 protein expression correlated with the clinical pathological features of nasopharyngeal carcinoma, and provide scientific based on the theoretical basis and method for nasopharyngeal carcinoma. Study on the targeted therapy and molecular targets of different] (1) 4EGI-1 treatment of nasopharyngeal carcinoma cell concentration, flow cytometry was used to detect the apoptosis rate of nasopharyngeal carcinoma, Western blotting detection of c-PARP Caspase-8, DR5, HIF-1, alpha, p-4EBP1 expression and DR4 protein, colony formation and detection of 4EGI-1 radiotherapy on nasopharyngeal carcinoma cell sensitization effect. (2) immunohistochemistry to detect the expression of DR4 and DR5 in nasopharyngeal carcinoma the protein level. Results (1) 4EGI-1 induced cell apoptosis, inhibit the proliferation of nasopharyngeal carcinoma; (2) 4EGI-1 increased c-PARP, nasopharyngeal carcinoma cell line Caspase8, the expression of DR5 and HIF-1 protein, decreased p-4EBP1 and DR4 protein expression; (3) 4EGI-1 2Gy and 4Gy increase the efficacy of radiation dose in treatment of nasopharyngeal carcinoma cells. The sensitization enhancement ratio was 1.195; (4) clinical stage III - IV nasopharyngeal carcinoma DR5 protein expression was significantly lower than the clinical stage of nasopharyngeal carcinoma. (5) the positive expression rate of DR5 protein in nasopharyngeal carcinoma with lymph node metastasis. Lower than that without lymph node metastasis, the positive expression of DR5 in nasopharyngeal carcinoma metastasis foci was significantly lower than that of matched primary nasopharyngeal carcinoma (6). Multivariate regression analysis showed that DR5 protein expression was significantly related to metastasis. Conclusion]1,4EGI-1 induced cell apoptosis inhibition of nasopharyngeal carcinoma cell proliferation activity in nasopharyngeal carcinoma and lymph node; increase the efficacy of radiation therapy.2,4EGI-1 nasopharyngeal carcinoma cell 4EGI-1 in nasopharyngeal carcinoma cells promote expression of DR5, c-PARP and Caspase8, the antitumor effect of.3 through activation of the death receptor pathway induced apoptosis, DR5 protein expression decreased to promote clinical progress of nasopharyngeal carcinoma and lymph node metastasis in patients with nasopharyngeal carcinoma; the expression of DR5 protein can be used as molecular lymph node metastasis of nasopharyngeal carcinoma and evaluate the treatment of our marker. The results for the anti nasopharyngeal carcinoma target similar 4EGI-1 structure to provide a scientific basis and theory to study medicine Basis. 18 drawings, 9 tables, 79 references.

【学位授予单位】：中南大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：R739.63

【参考文献】