低剂量辐射对肿瘤细胞增殖及小鼠免疫力影响

发布时间：2018-05-02 02:08

本文选题：低剂量辐射 + 适应性效应　；参考：《山西医科大学》2017年硕士论文

【摘要】：目的:低剂量辐射对正常细胞的适应性效应及兴奋效应是当前研究的热点,由于其适应性效应可显著降低放疗对正常细胞的损伤,同时对肿瘤细胞的有一定抑制作用,导致其适应性效应在临床研究中成为热点。然而低剂量辐射生物效应还包括超敏感性、旁效应等,影响其生物学效应的因素包括辐射剂量、辐射品质以及生物本身的特异性。一方面我们看到了低剂量辐射在临床及社会实际生活的广阔应用前景,一方面低剂量辐射的效应机制仍有诸多未明之处,导致难以对其进行令人信服的损伤评价,极大限制了它的应用前景。因此对低剂量辐射的研究仍需深入。本研究观察体外实验低剂量辐射对Lewis细胞生长速度、成活率、迁移及侵袭能力的影响,同时通过体内试验观察低剂量辐射与恶性肿瘤双重影响下免疫机体机能的变化情况。方法:本实验分为体外和体内试验两部分,体外实验将Lewis细胞分为四组,分别以0 Gy、12.5 mGy、25 mGy、50 mGy剂量伽马射线按两天照射一次的频率照射15次后,以克隆形成率、MTT实验、划痕实验、transwell实验检验细胞成活率、生长速率、迁移能力、侵袭力变化情况。体内试验分两批进行,一批将经照射后细胞植入小鼠腋下,另一批将未经处理的肿瘤细胞植入经照射小鼠腋下。然后观察记录小鼠及肿瘤各项指标。结果:1.体外实验克隆形成率实验组按剂量不同分别较对照组降低17.8%、21.8%、65.0%,生长速率较对照组降低9.4%、22.5%、25.7%,迁移能力较对照组提高65.8%、90.9%、125.2%。,侵袭能力较对照组增强90.2%、116.6%、193.8%。体内试验切片可见部分接种照射细胞的小鼠有肺部转移,对照组则无。2.溶酶体染色实验48h测得吸光值与0 Gy相比12.5 mGy、25 mGy和50mGy分别增加8.6%、14.6%、17.8%。72h测得吸光值与0 Gy相比12.5 mGy、25 mGy和50mGy分别增加14.3%、17.0%、24.4%。3.ELSA实验实验组小鼠与对照组有显著不同,其中IL-6在12.5 mGy、25 mGy和50mGy组中较0Gy组分别增加55.6%、114.8%、229.6%。IFN-γ在12.5 mGy、25 mGy和50mGy组中较0Gy组分别增加32.2%、98.9%、133.3%。测得各组肿瘤重量12.5 mGy、25 mGy和50mGy较0Gy组分别减少15.9%、40.6%、63.4%。结论:体外实验说明低剂量辐射对肿瘤细胞的增值能力有明显抑制,但对肿瘤细胞的迁移侵袭能力有增强作用,体内试验也证明了这点。体内试验通过组间小鼠对比,低剂量辐射对小鼠免疫力有增强作用。
[Abstract]:Objective: the adaptive effects and excitatory effects of low dose radiation on normal cells are the focus of current research. Because of their adaptive effects, the damage to normal cells caused by radiotherapy can be significantly reduced, and the tumor cells can be inhibited to a certain extent. As a result, its adaptive effect has become a hot spot in clinical research. However, biological effects of low dose radiation also include hypersensitivity and side effects. The biological effects of low dose radiation include radiation dose, radiation quality and biological specificity. On the one hand, we see the broad application prospect of low dose radiation in clinical and social life, on the other hand, the mechanism of low dose radiation is still not clear, which makes it difficult to make convincing damage evaluation. The prospect of its application is greatly limited. Therefore, the study of low dose radiation still needs to be further studied. In this study, we observed the effects of low dose radiation on the growth rate, survival rate, migration and invasion ability of Lewis cells in vitro, and observed the changes of immune function under the double effects of low dose radiation and malignant tumor in vivo. Methods: in vitro and in vivo experiments, Lewis cells were divided into four groups. Lewis cells were irradiated at a dose of 0 Gy 12.5 mGy ~ (25 mGy) ~ (50 mGy) for 15 times at a frequency of one day for 15 times, and the colony formation rate was determined by MTT assay. The cell survival rate, growth rate, migration ability and invasiveness were examined by scratch test and transwell test. In vivo experiments were carried out in two batches. One batch of irradiated cells were implanted into the armpit of mice and the other batch of untreated tumor cells were implanted into the axillary of irradiated mice. Then the indexes of mice and tumor were observed and recorded. The result is 1: 1. Compared with the control group, the rate of colony formation in vitro in the experimental group was lower than that in the control group by 17.81.821.80.The growth rate of the experimental group was lower than that of the control group, the growth rate was lower than that of the control group, the migration capacity of the experimental group was increased by 65.80.90. 9% and 125.2%, and the invasiveness of the experimental group was increased by 90.26.6193.83.85.7than that of the control group. In vivo test sections showed that some of the mice inoculated with irradiated cells had lung metastasis, while the control group had no. 2. 2. After 48 hours of lysosomal staining, the absorptivity values of 12.5 mGy (25 mGy) and 12.5mGy (25 mGy) and 50mGy (50mGy) of lysosome staining were increased by 8.6and 14.6and 14.6and 17.8g / 72h, respectively. Compared with 0 Gy, the absorbency values measured at 12.5mGy 25 mGy and 50mGy increased 14.3Gy 17.0g 24.44.3.There were significant differences between the experimental group and the control group. IL-6 in 12.5 mGy 25 mGy and 50mGy group increased 55.6and 114.8% and 229.6%, respectively. IFN- 纬 in 12.5 mGy 25 mGy group and 50mGy group increased 32.299% and 133.3%, respectively, compared with 0Gy group. The tumor weight of each group was 12.5mGy ~ 25 mGy and 50mGy decreased 15.9mGy ~ (25) and 63.40.The tumor weight of each group decreased by 15.9mGy ~ (25) mGy and 50mGy respectively. Conclusion: in vitro experiments showed that low dose radiation significantly inhibited the proliferation of tumor cells, but enhanced the ability of migration and invasion of tumor cells, which was also proved by in vivo experiments. In vivo test, low dose radiation enhanced immunity of mice by comparison between groups.
【学位授予单位】：山西医科大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：R730.5

【参考文献】