【作者】 魏冬；

【导师】 何庆泗；

【作者基本信息】 山东大学 ， 外科学， 2005， 硕士

【摘要】 研究背景 结肠癌是我国常见的恶性肿瘤之一,其发病率呈逐渐上升趋势。目前结肠癌的治疗仍以手术为主,辅以放疗、化疗等方法。近年来,诊治水平虽然不断提高,但总体上预后仍差,尤其是中晚期结肠癌患者,因此,对结肠癌的深入研究是我国肿瘤研究的重要课题。20世纪80年代以来,随着细胞分子生物学、生物工程技术的迅猛发展,使肿瘤生物治疗成为攻克恶性肿瘤的又一个极有希望的亮点。近年来,肿瘤的基因治疗已取得长足进展,在消化、神经、血液系统等已有肯定疗效。肿瘤联合基因治疗是一种全新的肿瘤治疗方法,迄今为止的实验研究已初步证实了肿瘤联合基因治疗的有效性、安全性及特异性,是传统疗法所不及的。应用野生型p53基因与双自杀基因系统联合治疗结肠癌可以发挥抑癌基因与双自杀基因系统的互补协同作用,可作为临床上优化自杀基因治疗方案的一种选择,且可望使结肠癌的基因治疗与目前的综合疗法得到较佳的契合,从而改善结肠癌患者的预后。在以往的体外实验中,我们已经证实WTp53基因对SW480细胞具有明显的生长抑制作用,并观察到一定的旁观者效应;同时亦通过体外实验证实,TK/GCV系统有明显的细胞杀伤作用,而CD/5-Fc系统的旁观者效应(bystander effect)更强,且TK/GCV、CD/5-Fc系统具有明显的协同作用;而且混合培养的SW480/TK-CD、SW480/p53细胞具有更为显著的生长抑制、旁观者效应及药物协同作用。为了进一步探讨WTp53基因联合TK/GCV、CD/5-Fc系统用于人结肠癌基因治疗的可能性,本课题通过建立SW480裸鼠移植瘤模型,在动物试验中应用WTp53基因联合TK/GCV、CD/5-Fc系统对人结肠癌进行治疗,证实其有效性,并探讨其作用机理,为结肠癌的联合基因治疗提供了新的思路和可靠的实验证据。更多还原

【Abstract】 Background Nowadays the incidence rate of human colocarcinoma becomes higher and higher. Surgery is always used as the main treatment of colocarcinoma, with some other ways, such as chemotherapy, radiotherapy and so on. In vitro test we have approved that WTp53 gene, TK/GCV and CD/5-Fc obviously inhibited the growth of SW480 cells, both TK/GCV and CD/5-Fc had bystander effect, and the combined genes had a greater antitumoral effect. So as to explore the probability of the gene therapy on human colocarcinoma with WTp53 gene and the System of TK/GCV and CD/5-Fc,we established the animal model of human colocarcinoma, treated them with genes above, and explored how they work. We have been expecting to supply the combined gene therapy on human colocarcinoma with new findings and credible experiment evidence.Objective To investigate the effect of the gene therapy on human colocarcinoma with WTp53 gene and the system of TK/GCV and CD/5-Fc, and to explore how the genes work.Methods The transplantation of cultivated cells was adopted. Nude mice were injected subcutaneously on the back with human colocarcinoma cells which belong to line SW480, so as to establish the animal model of human colocarcinoma. 48 nude mice were divided into 6 groups at random, which were comparison group,the group of WTp53,the group ofTK/GCV, the group of CD/5-Fc, the group of the system of TK/GCV and CD/5-Fc, the group of WTp53 and the System of TK/GCV and CD/5-Fc, and each group had 8 nude mice. WTp53 genes were mediated by Lipofectamine and TK> CD genes were mediated by the reverse transcription virus, and they all were injected directly into the tumor. Nude mice common status, tumor’s bulk, tumor’s weight, inhibition rate of tumor’s growth, pathology, survival period, et al,were investigated.Results Each treated group especially the combined gene therapy group obviously inhibited the tumors’ growth and prolonged the survival period significantly. The difference was significant between comparison and treated groups, and the combined gene therapy group worked more markedly. There was mutual effect between WTp53 gene and the system of TK/GCV and CD/5-Fc.Conclusions WTp53^ TK/GCV> CD/5-Fc obviously inhibited the growth of human colocarcinoma cell line SW480, and the combined genes had a greater antitumoral effect. They will have been probably used as the gene therapy of human colocarcinoma in the future.Significance We have succeded in establishing the animal model of human colocarcinoma in this experiment. In vivo test, the treatment of the gene therapy on human colocarcinoma with WTp53 gene and the system of TK/GCV and CD/5-Fc was significant. At the same time we have explored how they work, and supplied the combined gene therapy on human colocarcinoma with new findings and credible experiment evidence. Now we can forecast that WTp53^K/GCV>CD/5-Fc will have been probably used as the gene therapy of human colocarcinoma in the future, and the combined genes may have a greater antitumoral effect.更多还原