载VEGF-ASODN PLGA纳米粒抑制大鼠肝癌新生血管生成的作用

Anti-angiogenesis effectiveness of VEGF antisense oligodeoxynucleotide loaded polylactic-co-glycolic acid nanoparticles in the treat ment of Walker-256 hepatoma in rats

目的研究VEGF-ASODN PLGA纳米粒对大鼠肝癌血管生成的抑制作用。方法建立大鼠Walker-256肝癌模型。48只大鼠随机分为4组,均采用肝动脉插管方法注射药物。A组生理盐水组,B组PLGA组,C组单纯反义ODN组,D组VEGF-ASODN PLGA纳米粒组。每组3只大鼠于治疗后1周行组织学及免疫组化检查,以抗CD34单克隆抗体显示血管内皮细胞,根据CD34阳性血管内皮细胞记数来测定肿瘤微血管密度(MVD)。结果常规病理检查,A、B组组织形态学相似,C组癌细胞巢减小,部分癌细胞核固缩,出现小片坏死灶,而D组癌细胞核固缩和核碎裂现象明显增多、核染色质浓缩、细胞体积缩小,并出现多个片状和灶性坏死;MVD测定显示:D组MVD值为(18.1±6.15),明显低于其他各组,相差非常显著(P<0.01)。结论载VEGF反义寡核苷酸纳米粒能更有效抑制肿瘤血管生成,降低肿瘤微血管密度。

Objective To study the anti-angiogenesis effectiveness by using VEGF ASODN loaded PLGA nanoparticles in the treatment of Walker-256 hepatoma in rats. Methods The planted Walker-256 hepatoma model were established in 48 rats. We examined the therapeutic effectiveness by using VEGF ASODN loaded PLGA nanoparticles on planted rat models via hepatic artery infusion. Four treatment groups were compared with 12 rats in each group： ① Normal saline （group A）; ② Nothing loaded PLGA （group B）; ③ AS ODN （group C）; ④ VEGF-ASODN loaded PLGA nanoparticles （group D）. Microvessel density （MVD） was evaluated with immunostained by anti-CD34 antibody in 3 rats for each group. Results Microscopically, the morphological features in group A was similar with that of group B. Tumors in group C is often characterized by reduced tumor nests, karyopyknosis and snip necrosis in some tumor cells. Compared with group C, the karyopyknosis and the karyorrhexis of the tumor cells were obvious increased in group D. Furthermore, the chromatin condensation, the contraction, the snip and focal necrosis of tumor cells were also demonstrated. Compared with other three groups, microvessel density （MVD） was significantly reduced in group D （18. 1 ± 6. 16, P〈0.01）. Conclusion Transarterial infusion of VEGF-ASODN loaded PLGA nanoparticles may significantly enhance the anti-angiogenesis effect in comparison with using ASODN alone in the treatment of Walke〉256 hepatoma in rats.