超声微泡介导的miR-21和miR-126克服紫杉醇耐药乳腺癌的实验研究

Ultrasound-mediatedmiR-21and miR-126overcome Paclitaxel-resistant Breast Cancer

目的miR-21和miR-126对乳腺癌紫杉醇耐药的影响。方法选择乳腺癌耐药细胞建立的乳腺癌皮下移植瘤模型50只作为研究对象,制备载miR-21和miR-126的超声微泡,随机分为对照组、空微泡组、miR-21微泡组、miR-126微泡组以及联合组,每组10只,观察各组小鼠肿瘤生长情况,绘制肿瘤生长曲线并计算抑瘤率,采用实时荧光定量RT-PCR法检测肿瘤组织miR-21和miR-126水平,采用免疫组织化学检测肿瘤组织中乳腺癌耐药蛋白(BCRP)、P-糖蛋白(P-gp)及多药耐药相关蛋白1(MRP1)的蛋白表达水平。结果与对照组及空泡组相比较,miR-21微泡组和联合组miR-21mRNA表达水平明显下调(P<0.05),miR-126微泡组和联合miR-126mRNA表达水平明显上调(P<0.05),对照组和空泡组肿瘤体积持续增加,与对照组和空泡组相比,联合组对肿瘤的肿瘤体积和肿瘤质量最小,体积抑瘤率和质量抑瘤率最高(P<0.05),miR-21微泡组和miR-126微泡组的抑制作用次之(P<0.05)。免疫组织化学结果显示,联合组BCRP、P-gp及MRP1阳性率分别为20.00%、10.00%和20.00%,均明显低于miR-126微泡组和miR-21微泡组(P<0.05)。结论miR-21和miR-126联合干预对乳腺癌耐紫杉醇小鼠皮下移植瘤生长具有协同抑制效应,为克服紫杉醇耐药乳腺癌提供了新的治疗途径及靶标。

Objective To investigate the effects of ultrasound-mediatedmiR-21 and miR-126 on paclitaxel resistance in breast cancer.Methods 50 subcutaneous breast cancer transplantation tumormodels established by drug-resistant breast cancer cells were selected as research objects.Ultrasonicmicrovesicles loaded withmiR-21 and miR-126 were prepared and randomly divided into control group,empty microvesicles group,miR-21microvesicles group,miR-126microvesicles group and combination group with 10mice in each group.Tumor growth ofmice in each group was observed.Tumor growth curve was plotted and tumor inhibition rate was calculated.Real-time fluorescence quantitative RT-PCR was used to detect the levels ofmiR-21 andmiR-126 in tumor tissues,and immunohistochemistry was used to detect the protein expression levels of breast cancer drug-resistant protein(BCRP),p-glycoprotein(P-gp)and drug-resistant drug-related protein 1(mRP1)in tumor tissues.Results Compared with the control group and the vacuole group,the miR-21mRNA expression level in themiR-21microbubble group and the combined miR-126microbubble group was significantly down-regulated(P<0.05),while the miR-126microbubble group and the combinedmiR-126mrna expression level was significantly up-regulated(P<0.05).The tumor volume in the control group and the vacuole group continued to increase.Compared with the control group and the vacuole group,the combined group had the smallest tumor volume andmass,and the highest tumor volume andmass inhibitory rate(P<0.05),followed by themiR-21 microvesicle group andmiR-126microvesicle group(P<0.05).Immunohistochemical results showed that the positive rates of BCRP,P-GP andmRP1 in the combination group were 20.00%,10.00%and 20.00%,respectively,which were significantly lower than those ofmiR-126microbubble group andmiR-21microbubble group(P<0.05).Conclusion The combined intervention ofmiR-21 andmiR-126mediated by ultrasonicmicrovesicle has a synergistic inhibitory effect on the growth of subcutaneous graft tumors in paclitaxel-resistantmice,providing a new therapeutic approach and target for overcoming paclitaxel-resistant breast cancer.