【作者】 吴二林；

【导师】 刘全宏；

【作者基本信息】 陕西师范大学 ， 动物学， 2005， 硕士

【摘要】 据WHO预测,恶性肿瘤将成为21世纪危害人类健康的头号杀手,但就目前肿瘤的治疗而言,特别是中晚期肿瘤,任何一种常规治疗(手术切除、化学疗法、放射疗法等)均不能单独成为一种根治肿瘤的手段,综合治疗已逐渐成为治疗肿瘤的主要方法。1989年,日本学者在光动力学疗法的基础上提出了一种新的抗肿瘤理论,即声动力学疗法(Sonodynamic Therapy,SDT)。该理论主要是利用超声能穿透深层组织并聚焦于特定的部位,激活富集在组织和细胞内的光敏剂产生协同效应这一特点,达到抗癌效果,从而弥补了光动力学疗法等的局限性。因此,SDT是具有重要理论研究意义和临床应用价值的抗肿瘤新思路,在肿瘤治疗的方法探索方面倍受关注。 SDT提出以来已得到迅速的发展,目前国内外学者主要以离体培养的人肿瘤细胞和动物移植肿瘤为研究对象,就不同的超声参数结合不同的光敏剂对肿瘤细胞和肿瘤的杀伤效应及机制做了探讨,并提出了各种理论。迄今为止,SDT仍处于实验阶段,距临床实践尚有一定的距离。为了更多积累声动力学疗法在理论研究方面的资料,从而进一步推动该疗法的发展,使其早日应用于临床实践,本论文在综合国内外研究进展的基础上,结合本实验室前期研究结果,依托国家自然科学基金项目“超声激活血卟啉诱导肿瘤细胞凋亡的分子学机制的研究”的支持,采用频率为1.43MHz、能量为1W/cm~2的低强度聚焦超声结合3.5ug/ml血卟啉浓度等实验参数,通过显微和超微结构等层次对超声结合血卟啉杀伤腹水型艾氏腹水瘤细胞(EAT)的动态变化过程进行了观察分析,同时利用AV-PI荧光双染、TUNEL法及免疫细胞组织化学等方法对超声结合血卟啉诱导EAT细胞凋亡以及与凋亡相关蛋白的变化进行了研究,最后通过加入自由基清除剂对超声结合血卟啉作用效应的影响和检测细胞中MDA的含量探讨了SDT的作用机理。得出的结论如下: 1、通过不同的时间段取材进行形态学观察分析,发现血卟啉可明显增强低强度超声对EAT细胞的杀伤程度,并且可对EAT细胞造成继发性损伤,其作用的敏感位点主要是细胞的膜性结构,其中线粒体是最易受损的膜性细胞器。 2、用形态学、AV-PI荧光双染和TUNEL法的研究均证实1.43MHz、1W/cm~2的聚焦超声可通过诱导EAT细胞凋亡而致其死亡。表明超声结合血卟啉在损伤细胞而使其死亡的同时还存在诱导肿瘤细胞凋亡致其死亡的作用模式。更多还原

【Abstract】 According to the predication of WHO, malignant tumor will be the first killer to human health in the 21th Century. As far as the actual condition is concerned, any single conventional cancer treatment available (resection, chemotherapy or radiotherapy et al) can hardly be a radical therapy to the patient with malignant tumor, especially those with middle or late stage ones on admission, combined therapy has been the main therapeutic means gradually. On the foundation of photodynamic therapy(PDT), Shin-ichiro V memura, a Japanese scholar, has brought forward a new antitumor theory-sonodynamic therapy(SDT). The antitumor effect of SDT is based on the synergistic effects induced by photosensitizer which can remain preferentially in tumor tissues much longer than in normal tissues when activated with ultrasound. Many scholars have paid close attention to SDT for its theoretical significance and clinical value.A rapid development has been got on the studing of SDT since its putting forward. At present, the studies on the SDT have focused mainly on the mechanisms of killing effects on the human cancer cells in vitro and animal tumors in vivo by using different ultrasound parameters and different photosentizer. So far the studying has been still in the stage of lab and has a far way for clinic. Based on the early studying results of our laboratory, studies of home and abroad, and assuming a part of work of "The Mechanism of Tumor Cell Apotosis Induced by Ultrasound Activated Hematoporphyrin"supported by National Nature Science Foundation, I adopted the frequency of ultrasound wave 1.43MHz, the low-intensity 1W/cm2 with duration of exposure of 120s in this paper to observe the antitumor effects on Ehrlich ascites tumor (EAT) in vitro and the potential mechanisms of action inducing this cytotoxicity, in order to promote the development of SDT and put it into clinical pratice early. The main conclusions are as follow:1. Morphology observed through sample preparation for different time that hematoporphyrin can significant enhance the damage degree of EAT induced by low-intensity ultrasound and lingering damages, the sensitive killing sites of SDT are membrane system and mitochondrion is the most site to be destroyed.更多还原