Bcr3/abl2和VEGF基因反义寡核苷酸联用增强对K562细胞的生长抑制作用

The Synergistic Effects of bcr3/abl2 and VEGF Antisense Oligodeoxynucleotides on K562 Cells

目的:研究BCR ABL和VEGF反义寡核苷酸联用对K5 62细胞株的作用及其相互作用的影响。方法:设计针对bcr3/abl2和VEGF的反义寡核苷酸(AS ODNs) ,应用脂质体Oligofectamine作为转染载体。在转染后72h进行台盼蓝染色细胞计数;建立裸鼠K5 62移植瘤动物模型,瘤内注射AS ODNs,观察肿瘤体积生长变化,组织学检测肿瘤血管密度和肿瘤细胞凋亡情况。结果:转染后72h ,各实验组与空白组相比,细胞增殖抑制率分别为1 3 .47% (ASO B3/A2组) ,1 2 . 79%(ASO VEGF组)和41 . 5 5 % (半量联合治疗组)。经过4次治疗后,与对照组相比,肿瘤生长抑制率分别为2 3 .1 8% (ASO B3/A2组) ,1 7. 2 8% (ASO VEGF组)和5 7 .83% (半量联合治疗组)。联合治疗组肿瘤生长速率显著低于单一治疗组,伴随明显的肿瘤细胞凋亡增加和肿瘤血管密度减少。结论:双基因反义寡核苷酸联合应用协同抑制K5 62细胞增殖,抗肿瘤作用明显优于单一治疗组,可为CML基因治疗提供一项新策略。

Objective: Stimultaneous targeting of BCR-ABL and VEGF could be a rational therapy for Philadephia1 leukemia. It was aimed at determining the in vitro and in vivo anti-tumor efficacy of bcr3/abl2 antisense oligodeoxynucleotides (ASO-B3/A2) in combination with VEGF antisense oligodeoxynucleotides (ASO-VEGF). Methods :Antisense oligodeoxynucleotides (AS-ODNs) were synthesized and transfected into K562 cells by Oligofectamine. Trypan blue exclusion assay was used to determine cell proliferation. A xenotransplant model of human K562 cells was established in nude mice. The mice were subsequently devided into four groups and received different treatments that were given respectively. The volume of subcutaneous tumors was measured, the number of microvessels was counted and the apoptosis of tumor cells was examined. Results: At 72 hours after transfection, the inhibition of K562 cell proliferation induced by 200nmol/L ASO-B3/A2, 200nmol/L ASO-VEGF or the combined treatment (100nmol/L each) was 13 47%, 12 79%, and 41 55%, respectively. In vivo, after a four-time therapy, the tumor growth inhibition rate in the ASO-B3/A2 group was 23 18%, 17 28% in the ASO-VEGF group and 57 83% in the combined group. In comparison with the mice treated with individual agents, the mice treated with both ODNs showed a slower growth of leukemia tumors, a reduction of microvessel density and an increased apoptosis in the tumors. Conclusion: The combination of BCR-ABL and VEGF AS-ODNs inhibits synergistically the growth of K562 cells in vitro and in vivo, and may provide a new strategy for CML treatment.