丝甘蛋白聚糖在乳腺癌对多柔比星耐药过程中的重要性研究

Investigation the Importance of Serglycinin the Drug-Resistance to the Doxorubicin in Breast Cancer

目的研究丝甘蛋白聚糖(serglycin)的表达高低是否会影响乳腺癌细胞系对多柔比星的敏感性。方法用瞬时干扰的方法敲低丝甘蛋白聚糖在MDA-MB-231中的表达水平,且用qRT-PCR,免疫荧光的方法验证敲低效率;用MTS法测定多柔比星在阴性对照(NC)组和Si-丝甘蛋白聚糖(Si-SG)组中的IC_(50)值,以及测定在0.018μmol·L-1多柔比星的作用下两组的增殖曲线;用克隆形成的方法观察在不同药物压力下两组克隆形成数的差异。结果瞬时干扰的效率达到70%以上;MTS方法检测Si-SG组的IC_(50)值以及药物压力下的增殖曲线均显著低于NC组;且在不同药物压力下的克隆形成能力也显著低于NC组。结论在MDA-MB-231中瞬时干扰丝甘蛋白聚糖能够显著增强MDA-MB-231对多柔比星的敏感性。

OBJECTIVE To explore whether knockdown serglycin＇s expression level in MDA-MB-231 cells by transient transfection can improve the sensitivity of breast cancer cells to the doxorubicin. METHODS At first,qRT-PCR,Western-Blot and immunofluorescence were used to examine the expression level in two different cell lines,MDA-MB-231 and MCF-7. Then serglycin＇s expression level in MDA-MB-231 was knocked down by using transient transfection,qRT-PCR and immunofluorescence were used to test the efficiency of this approach; and then,between the NC group and the Si-SG group,MTS was used to measure the IC_（50） of doxorubicin and the proliferation curve under the treatment of the doxorubicin. Also the numbers of colony formation in this two groups was observed when treating with different concentration of doxorubicin. RESULTS It was found that in these two cells,the expression of serglycin in MDA-MB-231 is significantly higher than MCF-7. The efficiency of knockdown in MDA-MB-231 is above 70%. In Si-SG group,the IC_（50） and the growth curve under treatment with doxorubicin is significantly lower than the NC group. Same results can be found in the colony formation assay,when treating with the doxorubicin,the decreasing rate of colony numbers is significantly quicker in the Si-SG group than NC group. CONCLUSION Knockdown serglycin＇ s expression level in MDA-MB-231 cells by transient transfection can improve the sensitivity to the doxorubicin.