耐药乳腺癌免疫治疗的实验研究

Pilot Study of Immunization Therapy on Drug-Resistance in Breast Cancer Bearing Mouse Model

目的:探讨耐药乳腺癌抗原负载的树突细胞(DC)与细胞因子诱导的杀伤细胞(CIK)联合培养后对同种乳腺癌荷瘤小鼠的可能治疗机制。方法:分离健康人外周血获得单个核细胞,分别诱导为DC和CIK细胞,将人类乳腺癌耐药细胞株MCF-7/ADR细胞的冻融物抗原冲击DC(AP-DC),分别将DC与CIK细胞共培养(AP-DC+CIK组、DC+CIK组),将细胞经尾静脉注入裸鼠体内,观察不同组荷瘤标本中MDR1的表达、肿瘤细胞凋亡及凋亡相关蛋白Bax和Bcl-2的表达。结果:AP-DC+CIK组、DC+CIK组、CIK组及生理盐水组MDR1/β-actin比值分别为0.14、0.57、0.81及0.98。生理盐水组、CIK组、DC+CIK组和AP-DC+CIK组平均凋亡指数差异有统计学意义(P<0.001)。各组Bcl-2及Bax蛋白表达的OD值差异有统计学意义(P<0.01),Bcl-2/Bax值AP-DC+CIK组<DC+CIK组<CIK组<生理盐水组。结论:经耐药乳腺癌抗原负载的DC与CIK共同作用后,诱导同种乳腺癌细胞凋亡强于单纯DC与CIK共同作用后及单独CIK的治疗效果。

Objective： To explore the possible mechanisms of immunization therapy, cytokine-induced killer （CIK） cells co-cultured with dendritic cells （DC）, on mutidrug-resistance breast cancer bearing mouse model. Methods： DC and CIK were cultured respectively from peripheral blood mononuclear cells （PBMC） derived from healthy individuals. MCF-7/ ADR, a kind of breast cancer cell line with multidrug resistance, was prepared to obtain the antigen lyses. CIK was co-cul- tured with DC pulsed or unpulsed by the above antigen lyses （AP-DC＋CIK and DC＋CIK）. The effector cells were injected into the tumor-bearing mice through tail intravenous. The expression of MDR1, tumor cell apoptosis and the expression of Bcl-2 and Bax were measured in 4 types of cells. Results：The ratio of MDR1 to β-actin was different in the above 4 types of cells, AP-DC＋CIK group was 0.14, DC＋CIK group was 0.57, CIK groupwas 0.81, and normal saline （NS） group was 0.98. The average apoptosis index was also significantly different in these 4 groups （P 〈 0.001）. The values of optical density （OD） of protein Bcl-2 and Bax were different in 4 types of cells （P 〈 0.05）. The value of Bcl-2/Bax was the lowest in AP-DC＋CIK group, and then followed by DC＋CIK group and CIK group. The value of Bcl-2/Bax was the highest in NS group. Conclu- sion： After CIK cells were co-cultured with DC loaded with multidrug resistance breast cancer antigen, the apoptosis of these breast cancer cells was higher than those of CIK cells co-cultured with DC and those of CIK.