免疫毒素与顺铂协同杀伤肿瘤细胞机制的探讨

Synergistic Cytotoxic Effect of Immunotoxin HEL-PE38KDEL and Cis-platin against Tumor Cells

背景与目的:免疫毒素HELβ-PE38KDEL(HeregulinEGFlikedomainβ1-PsedomonasAeurginosa38KDEL,本文简称ITH)已经被证实是一种具有特异性杀伤erbB2、3、4阳性乳腺癌细胞的新的生物学制剂,然而它与化疗药物的联合作用效果目前尚未有报道。本文探讨ITH与化疗药物顺铂(DDP)的协同抗肿瘤作用。方法:采用AnnexinV结合实验和Westernblot检测乳腺癌细胞MDA-MB-453、2LMP和胃癌细胞N87分别在ITH和DDP单独及联合用药前后的细胞凋亡变化。结果:在高表达erbB-2、3、4的MDA-MB-453和N87中,联合用药组和单药组相比,凋亡细胞成倍增加(P<0.01);而在低表达erbB-2、3、4的2LMP,联合用药组和单药组相比,凋亡细胞无明显增加(P>0.05)。MDA-MB-453和N87细胞在联合用药组中PARP、caspase-3降解增加,bcl-2、mp53过度表达受抑制;而2LMP细胞中PARP、caspase-3降解无增加,bcl-2、mp53过度表达未受抑制。结论:ITH和DDP联合后可促进高表达erbB-2、3、4的乳腺癌细胞凋亡,这可能是两者协同作用的机制之一。

Background and Objective:The immunotoxin of HEL PE38KDEL has been proven to be a novel biological reagent which has specific cytotoxic effect against breast cancer cells with positive erbB 2, 3, 4. However it has not been tested the interaction of the immunotoxin and the conventional chemical anti cancer drugs. This study was designed to investigate the mechanism of the synergistic effect between HELβ1 PE38KDEL and cisplatin. Methods:The tests of Annexin V binding and Western blot were performed to detect the apoptosis in the breast cancer cell lines MDA MB 453, 2LMP, and the gastric cancer cell of N87 treated with single or drug combination. Results:In MDA MB 453 and N87 with high expression of erbB 2,3,4, percentage of the apoptosis cell was significantly higher in the group treated with the drug combination than that in the group treated with the single drug (P< 0.01). To the contrast, in 2LMP cells with low expression of erbB 2,3,4, there was no difference between the drug combination and the single drug group (P >0.05). In MDA MB 453 and N87, degradation of PARP, caspase 3 was more in the group treated with the drug combination than that in the group treated with the drug alone. Overexpressions of bcl 2, mp53 were inhibited in the group treated by the drug combination. On the contrary overexpressions of bcl 2, mp53 were not inhibited in the group treated with the single drug. While these changes of PARP[poly (ADP) ribose polymerase], caspase 3, mp53, bcl 2 could not be observed in the control cell line of 2LMP. Conclusions:The combination of HELβ1 PE38KDEL and cis platin could promote the synergistic effect on apoptosis in the target cancer cells with high expression of erbB 2,3,4 which might be one of the mechanism of these two drugs.