超声波体内逆转肿瘤多药耐药基因表达的实验研究

Ultrasonic Therapy Induces Inhibition of Expression of Multidrug Resistance Genes in HepG2/ADM Cells in vivo

目的:探讨超声波体内逆转肿瘤多药耐药的有效性及其逆转机制。方法:70只HepG2/ADM移植瘤裸鼠随机分成对照组(10只),ADM组(20只),超声组(20只),ADM联合超声组(20只),治疗28天后收集标本。应用RT-PCR法和免疫组织化学法检测多药耐药相关基因和蛋白(MDR1,MRP和LRP)表达。结果:超声治疗组能显著逆转裸鼠HepG2/ADM移植瘤多药耐药基因的表达。免疫组化结果显示,超声治疗组和ADM联合超声组的P-gp,MRP阳性表达显著降低;与对照组相比,在超声治疗组和ADM联合超声治疗组P-gp,MRP水平明显降低。RT-PCR结果显示,超声组和ADM联合超声组能明显降低HepG2/ADM移植瘤细胞MDR1 mRNA和MRP mRNA的表达。结论:多种机制参与超声波逆转肿瘤多药耐药,超声波通过下调MDR1和MRP mRNA和蛋白表达水平,增加细胞内药物浓度等途径逆转肿瘤多药耐药。

To investigate the reversal efficacy of ultrasonic （US） therapy on multidrug resistance （MDR） in HepG2/ADM cells in vivo and to study the underlying mechanism. Methods： A total of 70 nude mice bearing HepG2/ADM tumors were randomized into the control group（n=10）, ADM group（n=20）, US group（n=20）, and ADM plus US group（n=20）. Tumor specimens were collected from the mice in each group 28 days after the interventions. Expression of the MDR-related genes MDRI, MDR resistance-associated protein （MRP） and lung resistance protein （LRP） were assayed by reverse transcription-polymerase chain reaction（RT-PCR） and immunohistochemistry. Results： US significantly reversed MDR in HepG2/ADM cells in nude mice. lmmunohistochemistry showed that expression of Pgp and MRP was significantly reduced in the US group and the ADM plus US group. Decreased expression of MDR1 and MRP mRNA in HepG2/ADM tumor cells was detected by RT-PCR in the US group and the ADM plus US group. Conclusion： US has strong reversal effects on MDR in HepG2/ ADM cells through multiple routes including downregulating MDR1 and MRP mRNA and protein ex- Dression and increasinz intracellular drug concentration.