Experimental treatment of sarcoma by high-intensity focused ultrasound

点击翻译按钮获取中文摘要

Background: Antitumor effects of HIFU (high-intensity focused ultrasound) has been investigated in several kinds of cancers, its effects on soft tissue sarcomas were rarely reported.Materials and Methods: Mouse soft tissue tumor model was made by a subcutaneous inoculation of sarcoma 180 cells (3x10^5). As the HIFU system, we used the transducer (HITACHI) and amplifier. The model tumor was treated by single shot of the HIFU, and their size, infiltration of macrophages and CD4 or CD8 positive lymphocytes, development of apoptotic cells, and mouse survival rate were observed until 6 weeks after the HIFU irradiation.Results: Size of the tumor was significantly smaller in HIFU-treated group than those in non-treated group. TRAP stain showed marked infiltration of macrophages around the remnant of the tumor cells in HIFU-treated group, but none in the non-treated group. Similarly, immunostain for CD4 or CD8 showed marked infiltration of lymphocytes in HIFU-treated group. Apoptosis surveyed by TUNEL method in the remnant tumor cells were occasionally observed in HIFU treated group, and the rate of apoptosis in HIFU-treated group was significantly higher than those in non-treated group. Survival of the sarcoma-bearing mouse in HIFU-treated group was significantly better than those in non-treated group.Conclusion: HIFU treatment for sarcoma may induced antitumor immunoresponses, even by a single shot.