增殖缺陷型腺病毒介导人内皮抑素基因抗乳腺癌的实验

Antitumor Efficacy of Human Endostatin Expressed by Replication-Deficient Adenovirus on Human Breast Cancer in Nude Mice

目的通过建立裸鼠乳腺癌肿瘤模型,在体内实验中进一步证实携带人内皮抑素基因的增殖缺陷型腺病毒Ad-hE的抗肿瘤作用。方法在BALB/c裸鼠皮下种植人乳腺癌细胞MCF-7,建立移植瘤模型。在瘤体内注射Ad-hE治疗,观察肿瘤生长,免疫组化检测肿瘤细胞内皮抑素的表达和计数肿瘤间质中微血管的数量。结果Ad-hE具有明显抑制肿瘤细胞生长的作用,瘤体内注射重组腺病毒后4周,Ad-hE治疗组肿瘤体积为(225.3±90.2)mm3,明显小于Ad-LacZ病毒对照组(794.9±189.8)mm3和空白对照组(890.7±102.5)mm3。免疫组化显示,乳腺癌细胞在感染腺病毒后能够有效表达内皮抑素,阳性细胞比率超过60%以上。Ad-hE治疗组瘤组织中血管数量(16.3±7.3)明显少于空白对照组(54.6±17.6)和Ad-LacZ病毒对照组(49.8±21.2)。结论增殖缺陷型腺病毒介导人内皮抑素的表达,具有明显抑制肿瘤细胞生长的作用。

Objective To establish human breast cancer xenografts in nude mice, and to investigate the antitumor efficacy of human endostatin expressed by replication-deficient adenovirus Ad-hE in vivo. Methods The mammary cancer cells MCF-7 were injected subcutaneously in BALB/c nude mice to establish the xenografts. The tumor growth was observed and measured after Ad-hE treatment. The immunohistochem/stry was used to examine the expression of endostatin in cancer cells and to calculate the density of microvessels in tumor matrix. Results Ad hE exerted an obvious effect of tumor growth inhibition. After 4 weeks later, the tumor volume of Ad hE treated group was （225.3 ± 90. 2）mm^3 , markedly less than that of Ad-LacZ group （794. 9 ± 189. 8）mm^3 or control group （890.7 ± 102.5）mm^3. The im munohistochemistry showed that, after infection of adenoviruses, the mammary cancer cells expressed endostatin efficiently with more than 60% of the positive cell rate. The density of microvessels （MVD） in tumor matrix of AdhE treated group （16. 3 ± 7. 3） was obviously lower than that of control group （54. 6 ±17. 6） or Ad LacZ group （49. 8 ± 21.2）. Conclusion The replication-deficient adenovirus mediated efficiently the expression of endostatin and exerted the inhibition effect on cancer cells. This antiangiogenesis gene therapy may serve as an effective means to overcome the difficult of cancer recurrence and metastasis.