绿茶对肺癌的干预及其机制初探

发布时间：2018-01-16 09:47

本文关键词：绿茶对肺癌的干预及其机制初探　出处：《南昌大学》2014年硕士论文　论文类型：学位论文

更多相关文章：肺癌绿茶 化学预防 P53 Survivin VEGF

【摘要】：目的: 肺癌在当今全球范围之内，已成为发病率增长最为迅速，而预后最差的恶性肿瘤。由于在肺癌的早期诊断方面，仍未发现高灵敏度的特异性检测技术和筛查方法，人们更迫切期待能通过日常饮食等手段，积极预防肺癌的发病。化学预防是癌症预防的关键要素。而更多的流行病学和实验研究证明，健康的饮食和生活方式等因素能明显降低肺癌的患病风险。茶是全球饮用范围最为普及的饮料之一。绿茶具有良好的防癌功效。人们期待，能通过饮用绿茶这种生活方式，有效的预防肺癌发病。与此同时，构建肺部恶性肿瘤动物模型是评估肺癌防治疗效必要的实验方法。本课题应用苯并芘，这种因吸烟及空气污染而产生的，在人们日常生活中接触最为频繁的高活性致癌物，经肺部穿刺操作，对实验大鼠进行注射，构建大鼠肺部恶性肿瘤动物模型，通过这一模型，达到评价绿茶对肺部恶性肿瘤的干预作用，并在此基础之上，更深入的研究绿茶对大鼠肺部恶性肿瘤组织在p53蛋白和survivin蛋白表达上的影响。同时，通过酶联免疫吸附试验，检测大鼠动物模型VEGF的表达，以此初步探明绿茶对肺部恶性肿瘤的干预机制。方法: 构建大鼠肺部恶性肿瘤模型。应用3,4-苯并芘粉末混于玉米油溶液，配制成混合溶液，每次均固定注射含有3,4-苯并芘2mg剂量的玉米油混合溶液0.2ml。使用10%水合氯醛腹腔注射麻醉后，于大鼠右侧3-4肋间经皮肺穿刺注射。对照组则使用纯玉米油溶液做肺部穿刺注射。各组均每隔2周操作1次，总共操作4次。在绿茶干预肺部恶性肿瘤实验组中，，仅使用绿茶作为日常的唯一饮料进行化学预防。而饮水组和对照组则使用饮用水作为日常的饮料。观察大鼠肺部恶性肿瘤病变过程，通过免疫组织化学方法，检测绿茶组和饮水组大鼠肺部肿瘤组织p53蛋白和survivin蛋白表达差异。同时，通过酶联免疫吸附试验，检测各组大鼠血清VEGF表达的差异。结果: 所有单纯接受玉米油溶液肺部穿刺注射的对照组大鼠，在52周实验周期内未发现肿瘤。饮水组在52周内恶性肿瘤发病率为65%，而绿茶组在52周内恶性肿瘤发病率明显下降，仅为20%。免疫组织化学结果显示:绿茶组肺部恶性肿瘤组织p53蛋白表达上调、survivin蛋白表达下调，且与饮水组比较，在表达差异上具有统计学意义(P0.05)。酶联免疫吸附试验检测结果显示:绿茶组VEGF表达下调，且与饮水组相比，在表达差异上具有统计学意义(P0.05)。结论: 绿茶对3,4-苯并芘致癌物所致的肺部恶性肿瘤具有较为明显的预防和干预作用。通过上调p53蛋白的表达，下调survivin蛋白和VEGF的表达是绿茶预防肺癌的重要机制。
[Abstract]:Objective: Lung cancer has become the most rapidly increasing incidence and the worst prognosis of malignant tumors in the world today, due to the early diagnosis of lung cancer. High sensitivity specific detection techniques and screening methods have not yet been found, and people are looking forward to daily diet and other means. Active prevention of lung cancer. Chemical prevention is a key element of cancer prevention. A healthy diet and lifestyle can significantly reduce the risk of lung cancer. Tea is one of the most popular drinks in the world. Green tea has a good anti-cancer effect. It can effectively prevent lung cancer by drinking green tea. At the same time, it is necessary to establish animal model of lung cancer to evaluate the curative effect of lung cancer. This highly active carcinogen, which is produced by smoking and air pollution, is the most frequently exposed carcinogen in people's daily life. It is injected into experimental rats through lung puncture to establish the animal model of lung malignant tumor in rats. Through this model, the intervention effect of green tea on lung malignant tumor was evaluated, and on this basis. To study the effect of green tea on the expression of p53 protein and survivin protein in lung malignant tumor tissues of rats. At the same time, enzyme linked immunosorbent assay (Elisa) was used. To investigate the mechanism of green tea intervention on lung malignant tumor, the expression of VEGF in rat model was detected. Methods: The model of lung malignant tumor in rats was established. The mixed solution was prepared by mixing 3o 4-benzo pyrene powder in corn oil solution and containing 3% in each injection. The dosage of 4-benzopyrene was 0.2 ml of corn oil mixed solution. 10% chloral hydrate was injected intraperitoneally after anesthesia. The right 3-4 intercostal lung puncture was performed on the right side of the rats, while the control group was injected with pure corn oil solution once every 2 weeks for a total of 4 times. In the experimental group of green tea intervention lung malignant tumor. Only green tea was used as the only daily drink for chemical prophylaxis, while drinking water was used as daily drink in drinking water group and control group. The pathological process of lung malignant tumor in rats was observed by immunohistochemical method. The expression of p53 protein and survivin protein in lung tumor tissue of green tea group and drinking group were detected. At the same time, enzyme linked immunosorbent assay (Elisa) was used. The difference of serum VEGF expression in each group was detected. Results: No tumor was found in all the control rats who received pure pulmonary puncture injection of corn oil solution. The incidence of malignant tumor in drinking water group was 65% within 52 weeks. However, the incidence of malignant tumor in green tea group decreased significantly within 52 weeks, only 20%. Immunohistochemical results showed that p53 protein expression was up-regulated in lung malignant tumor tissue of green tea group. The expression of survivin protein was down-regulated and compared with the drinking water group. The results of Elisa showed that the expression of VEGF in green tea group was down-regulated and compared with that in drinking water group. The difference of expression was statistically significant (P 0.05). Conclusion: Green tea has obvious preventive and interventional effects on lung malignant tumors caused by carcinogens of 3o 4-benzo pyrene. It can up-regulate the expression of p53 protein. Down-regulating the expression of survivin protein and VEGF is an important mechanism of preventing lung cancer in green tea.
【学位授予单位】：南昌大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：R734.2

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