利用拉曼光谱检测肝癌、鼻咽癌细胞及其在端粒酶抑制剂作用后的分子变化

【作者】 朱淼；

【导师】 舒雨雁；

【作者基本信息】 广西医科大学 ， 生物化学与分子生物学， 2006， 硕士

【摘要】 癌症是目前世界上危害人类健康和生命的最主要疾病之一,大量的临床实践表明:通过早期诊断、及时有效的治疗,可以在相当程度上控制肿瘤的发展,并大大提高病人的生存机会。拉曼光谱技术是分析物质结构的有效手段,能够在分子水平上反映出肿瘤细胞早期在化学组成和分子结构上所发生的变化,为癌症的早期诊断及其癌变机理分析提供重要的信息。鉴于端粒酶的激活普遍存在于恶性肿瘤中,是肿瘤细胞获得永生性的关键和肿瘤组织无限增殖的必要条件,端粒酶已成为目前最为广谱的肿瘤分子标志物及肿瘤基因治疗的新靶点之一。但对于端粒酶活性的调节机制的研究仍处于探索阶段,端粒酶抑制剂的生化特性及抗肿瘤的作用机理还有待进一步的研究。本文利用单细胞光镊拉曼光谱技术研究人肝癌细胞SMMC-7721、正常肝细胞LO₂及人鼻咽癌细胞CNE2、正常鼻咽部上皮细胞HBE,通过光谱的对比分析,从而寻找反映癌变的特征标志光谱。应用多种端粒酶抑制剂作用于肝癌、鼻咽癌细胞,通过对比端粒酶抑制剂作用前后的拉曼光谱,可见细胞在端粒酶抑制剂作用后的分子改变,探讨其抑制端粒酶活性的可能机制。结果如下:1.实验结果显示正常细胞和癌细胞的拉曼光谱有明显的差异。根据光谱,可以看出细胞在癌变后,核酸、蛋白质、脂类等重要生物分子在结构或含量上都发生了不同的改变。在肝癌细胞SMMC-7721和鼻咽癌细胞CNE₂中核酸的含量大大增加,脂类物质明显减少。肝癌细胞的蛋白质二级结构、侧链氨基酸残基都发生了改变,分子间氢键受到破坏。用I₁₃₀₃/I₁₃₃₆的比值等于1.1来区分正常鼻咽部上皮细胞与鼻咽癌细胞的灵敏度、特异度更多还原

【Abstract】 Cancer is one of the main diseases that threaten peoples’ health and life at present. A great deal of clinical practice indicated that the development of cancer could be controlled through early diagnosis and valid treatment to improve the chance of survival. Raman spectrum is an effective method for analyzing substance structure .It can represent the differences of chemical composition and molecular constitution in the tumor cell at molecular level, and these differences may provide some important information for the diagnose of cancer and the analysis of canceration mechanism. Since the activation of telomerase has been found universally in human cancers and telomerase is the key for the existence of tumor cells and is also the necessary condition for the proliferation of tumor tissue, telomerase has been explored as a promising biomarker and target in cancer gene therapy. It is at the exploring stage to the research for regulatory mechanism of the telomerase activity, and the biochemical characteristic and antitumor mechanism of the telomerase inhibitors should be further researched.In this thesis, unicell tweezers Raman spectroscopy is used to study the hepatocyte LO₂、hepatoma carcinoma cell SMMC-7721 and nasopharyngeal epithelial cell HBE、nasopharyngeal carcinoma cell CNE₂. Characteristic spectrum can be founded through the comparing and analyzing of the spectrum. To discuss the mechanism of telomerase inhibitors on cancer, hepatoma carcinoma cell SMMC-7721 and nasopharyngeal carcinoma cell CNE₂ treated by 8 telomerase inhibitors were studied. The molecule changes can be seen from the treated cancer cell. The main results are as follows:1. Experimental results have demonstrated that Raman spectra of malignant cells were significantly different from those of normal cells. Biological molecules such as DNA, protein, lipid undergo a series of changes in content or structure .In hepatoma carcinoma cell SMMC-7721 and nasopharyngeal更多还原