聚焦超声激活血卟啉对H-22肿瘤细胞的杀伤作用

A preliminary study of the killing effect of focused ultrasound and ultrasound-hematoporphyrin on H-22 tumor cells

目的研究声动力学疗法(SDT)杀伤肿瘤细胞的最佳声照处理时间点,探讨不同强度的聚焦超声激活血卟啉对H-22肝癌腹水瘤细胞的杀伤作用。方法采用荧光分光光度法测定血卟啉衍生物(HpD)在H-22肿瘤细胞内的富集时间,选择最佳声照处理时间点。采用频率为1.43 MHz,强度分别为1W/cm^2、2 W/cm^2和3 W/cm^2的聚焦超声结合血卟啉作用于H-22肿瘤细胞,于不同时间段取材,通过扫描电镜观察细胞表面的超微结构变化,并与单纯血卟啉或单纯超声处理后的细胞进行比较。结果加入HpD后45 min,肿瘤细胞内药物含量最高,作为最佳声照处理时间点。形态学观察显示:单纯血卟啉处理对H-22肿瘤细胞仅有轻微影响;单纯超声处理对细胞有一定的损伤作用,并且细胞受损程度随着超声强度的增大和取材时间的延迟而逐渐加重;超声结合血卟啉对细胞的协同杀伤效应在同等条件下显著高于单纯超声处理的细胞。结论SDT对H-22肿瘤细胞的损伤效应依赖于超声强度以及声敏剂在细胞内的含量,并且表现出一定的时间相关性变化。

Objective To study the killing effect of focused ultrasound activated-hematoporphyrin on H-22 and its optimum exposure time. Methods The distribution of hematoporphyrin in H-22 cells was measured by a fluorescence photometer, the uhrastructure changes were evaluated at different time with a scanning electron micro- scope after treatment with focused ultrasound at the frequency of 1. 43 MHz and intensity of 1. 0 W/cm^2, 2.0 W/cm^2 , 3.0 W/cm^2 , respectively, in combination with HpD. Results The concentration of HpD in the H-22 cells reached its peak after being added to H-22 tumor cells for 45 minutes, which will produce the best anti-tumor effect when activated by ultrasound. Morphological observation showed that HpD alone had a slight influence on H-22 cells; Ultrasound alone showed an anti-tumor effect on tumor cells, which was dosage-dependent. Ultrasound diathermy in combination with HpD has more effective in terms of its antitumor effect when compared with ultrasound diathermy alone. Conclusion The killing effect on H-22 tumor cells of sonodynamic treatment was dependent on the intensity of ultrasound and the content of HpD in the cells, as well as on the time of action of both ultrasound and HpD.