| Summary: | 碩士 === 國立交通大學 === 生醫工程研究所 === 107 === In recent years, due to multiple reasons including westernization of diet and irregular lifestyle, etc., the breast cancer has become the most prevalent cancer among Taiwanese female, and the incident rate has an increasing trend. Nowadays, the common treatment of breast cancer is effective, yet still can be improved, for instance, reducing side effects, lowering treatment prices, and using non-invasive treatment. Ultrasonic is well known for its non-invasive, deep penetrating and non-ionizing radiation ability. Ultrasound has seen development not only as a diagnostic imaging modality but also as a therapeutic modality. For instance high intensity focused ultrasound（HIFU）has been applied in clinical thermal tumor ablation. On the other hand, the non-thermal effects like cavitation can have a great effect on biological effect, such as high pressure induced by bubble explosion and the generation of free radicals. Therefore, we use the ultrasonic cavitation to do the breast cancer therapy. The traditional 2D cells culture were first used to find the effective parameters, then conduct the experiment in 3D cell culture hydrogel to mimic the natural environment. This experiment use a 1 MHz focused ultrasound probe. After ultrasound exposure, measuring the cell viability, cell death and the increase of ROS within the cell. The results show that there is a different ultrasonic effect between 2D and 3D culture. In 2D cells culture, the cell viability has a little decrease at first, but it recovered after 24 hours. Different from 2D, 3D cultured cells were affected by free radicals after 24 hours that the activity reduce about 19 %. From this study, the main mechanism by which the ultrasonic parameters used in this experiment reduce the activity of breast cancer cells is the free radicals generated by the cavitation effect.
|
|---|
