低频超声联合微泡增强脂质体介导的野生型p53转染DUl45细胞诱导早期细胞凋亡

Apoptosis induced by the transfection of wild-type p53 gene into DU145 cells through 20 kHz ultrasound combined with microbubbles and iiposome

目的研究低频低能量超声联合微泡增强脂质体介导的野生型p53质粒转染促进人前列腺癌DU145细胞的早期细胞凋亡，及与β53-MDM2形成的负反馈环关系。方法以频率20kHz、声功率为80mw的超声，采用连续波辐照，实验分4组：空白对照组（A组）、单纯超声联合微泡组（B组）、脂质体转染组（c组）和超声加微泡联合脂质体转染组（D组），其中B、D组每毫升细胞悬液加微泡200μlC、D组每毫升细胞悬液加质粒8μg、脂质体20μg，处理后细胞继续培养24h，流式细胞仪检测细胞早期凋亡情况，36h后Westernblot检测细胞中p53蛋白及MDM2蛋白的表达量。结果流式结果显示D、C组的早期细胞凋亡率高于A、B组，差异有统计学意义（P〈0．01），以D组与A、B组的差异最明显，D组的早期细胞凋亡率亦高于c组，差异有统计学意义（P〈0．01）；Westernblot显示D、c组p53表达较A、B组表达增加，同时MDM2的表达较A、B组表达减少，差异有统计学意义（P〈0．01），以D组变化最明显，D组与c组比较差异也有统计学意义（P〈0．01）。结论超声联合微泡促进脂质体介导的野生型p53质粒转染人雄激素非依赖型前列腺癌DUl45细胞，可明显提高癌细胞的早期细胞凋亡率，这种重新表达野生型p53蛋白的DUl45细胞早期细胞凋亡率的提高可能与上调p53蛋白、下调MDM2蛋白的表达有关。

Objective To investigate whether the transfection of wild-type p53 gene into DU145 cells through 20 kHz ultrasound combined with microbubbles and liposome can induce cell apoptosis, and to explore the probable mechanism. Methods Ultrasound with a frequency of 20 kHz and power of 80 mW in continuous wave mode was used to transfect wild-type p53 gene into DU145 cells, and microbubble and liposome were added. DU145 cells were divided into four groups： control group（A）, ultrasound combined with microbubbles group（B）, liposome group（C）, and ultrasound combined with microbubbles and liposome group（D）. Twenty-four hours after treatment, the early apoptosis was detected by flow cytometry, and western blotting was used to evaluate the expression of the apoptosis-related proteins, p53 and MDM2, after treatment for thirty-six hours. Results The early apoptosis rate of group D was much higher than that of group A,B and C（ P ~ 0. 01 ）. Western blotting showed that the treatment of group D increase the expression of p53 protein and decreased the expression of MDM2 protein,which has a significance difference when compared with group A,B and C（ P d0. 01 ）. Conclusions The treatment of transfection wild-type p53 gene into DU145 cells through 20 kHz ultrasound combined with microbubbles and liposome induce cell apoptosis may through up-regulation of p53 and down-regulation MDM2.