The Effect Of The Ultrasound Activated Hematoporphyrin On Cytoskeleton Of Ascite S180 Tumor Cell

Cancer is one of the fatal diseases threatening people's health at present though the investigations of antitumor have been carrying on hundreds of years. There are many methods to cure tumors. Surgical, radiotherapy, chemotherapy, are normal method. However, chemotherapy and radiotherapy hurt human body seriously. Surgical can result in transferring tumor cells to other part of human body through blood circulation. In 1978, American scholar Doughtery put forward Photodynamic Therapy (PDT) which was already applied to the clinical treatment of tumors. Because of the weak penetration of light, Photodynamic Therapy was used mostly to treat tumors located in human skins, but not those in deeper part of human bodies. Japanese scholar Umemura raised the Sonodynamic Therapy (SDT) based on the PDT in 1989. This therapy is based on the ultrasound which can penetrate deep into the tissue and activate sonosensitizer that was accumulated in tumor. Sonosensitizer, such as Hematoporphyrin (Hp), can accumulate in tumor cells specifically, can do little harm to natural tissue, so it can cure cancer and relieve damage to human body. Recent years, scholars have been investigating this therapy for decades extensively and deeply, including the mechanism such as cavatition, singlet oxygen, hydroxide radicals, alkyl oxygen radicals, choice of sonosensitizer of antitumor drugs, such as Hp and other compounds. Morphological changes after SDT treatment suggest that there are two effect model: necrosis and apoptosis. Early studies in our laboratory suggested that the killing effect of the ultrasound associated with Hp on S180 cells could greatly decrease the ability to live. The study shows that ultrasound associated with Hp inhibited the expression of cytoskeletal proteins, and lead tumor cell to death or apoptosis.The paper is a part work of "Studies on Molecular Biological Mechanism of tumor cell's Apoptosis induced by Ultrasound Activated HpD" which is supported by National Nature Science Foundation. Focused ultrasound which has the frequency of 1.34MHz and intensity of 3W/cm~2 is used to detect the changes of cytoskeletal proteins after tumor cells treated by ultrasound associated with Hp. The results are as follows:1. Effect of sonodynamic therapy on cytoskeleton of Ascite S180 tumor cell: This article adopted immunocytochemistry to study the expression of Actin, Tubulin, Vimentin after the S180 tumor cells treated by ultrasound which is associated with Hp. The result indicates that the cooperation of ultrasound and Hp inhibited the expression of protein more seriously than the ultrasound alone. It has little inhibition to protein expression using Hp alone. Ultrasound associated with Hematoporphyrin strengthened the effect of solo ultrasound. It inhibitted the expression of Actin, Tubulin and Vimentin. It inhibited the cell division, reproduction, survival ability and it resulted in necrosis and apoptosis.2. Effect of sonodynamic therapy on nuclear skeleton of Ascite S180 tumor cell: expression changes of Lamina and LaminB are detected by immunocytochemistry after S180 cancer cells were treated. by ultrasound associated with Hematoporphydn, protein expression continued to decrease when the time went by. The expression of Lamina and LaminB decreased abruptly 3 hours after the treatment. Lamina is more sensitive to the treatment than LaminB. The result indicated that the cooperation of ultrasound and Hematoporphyrin highly inhibitted the expression of Lamina and LaminB than the ultrasound group. It has little inhibition to the expression of Lamina and LaminB using Hematoporphyrin alone.The article basically involved the influence of cytoskeletal proteins after SDT. It also indicated the mechanism of cell necrosis and apoptosis and provided some data for SDT.