Ling Chun-hua, Ji Cheng, Chen Yan-bin, Fu Jian-xin, Zhou Ju-ying, Chen Wei-chang, Yang Ji-cheng, Su Liao-yuan
Department of Respiratory Medicine, First Affiliated Hospital of Suzhou University, Suzhou, China.
Zhonghua Jie He He Hu Xi Za Zhi. 2004 Oct;27(10):683-6.
The combined inhibition effects of endostatin gene transfer and ionizing radiation on lung adenocarcinoma model of A549-cell were investigated.
Human endostatin gene was transferred into lung adenocarcinoma A549 cell by retrovirus-mediation to obtain an A549/Endo cell. A549 and A549/Endo cells were xenoimplanted in nude mice respectively (each group included 10 mice). Then, the changes of the tumor size of each group (n = 5) and its growth inhibition rate were estimated. The implanted tumors of each group (n = 5) were exposed to radiation with 20 Gy at 28 day after implantation. They were irradiated again with 20 Gy 3 day later. The ionizing radiation was strictly confined to the tumor by shielding the rest of the body with lead. The size of tumor was measured periodically. The microvessel density (MVD) of 4 groups of implanted tumors (A549, A549/Endo, A549 + IR and A549/Endo + IR) were compared on day 42 postgrafting by the immunohistochemical method.
PCR confirmed that endostatin gene was inserted into the genomic DNA of human lung adenocarcinoma A549 cell. The tumor formation time showed significant difference (P < 0.05) between group A549 (7.8 +/- 1.6) d and group A549/Endo (12.2 +/- 1.7) d. At the time of day 42 postgrafting, the tumor sizes of group A549 and group A549/Endo were (927.8 +/- 269.2) mm3 and (217.5 +/- 81.5) mm3 respectively (P < 0.01), and the tumor growth inhibition rate was 76. 5%. At the time of day 14 after irradiation, the tumor sizes of group A549 and group A549/Endo were (157.7 +/- 49.0) mm3 and (4.6 +/- 2.9) mm3 respectively (P < 0.01). The results of immunohistochemical detection showed that the MVD of-A549/Endo implanted tumor was significantly decreased [21.62 +/- 3.55 compared with A549 implanted tumor 35.78 +/- 5.67 (P < 0.01)]. Moreover , it also showed that ionizing radiation could further reduce the MVD of A549/Endo implanted tumor from 21.62 +/- 3.55 to 11.32 +/- 2.78 (P < 0.01).
Retroviruses can highly mediate the transfer of endostatin gene into the adenocarcinoma cells. Endostatin gene transfer can inhibit the xenoimplanted tumor growth by its direct inhibition on neovascularization. The combination of endostatin gene transfer with ionizing radiation treatment can synergistically inhibit the neovascularization and the growth of lung adenocarcinoma.
研究内皮抑素基因转染联合电离辐射对A549细胞肺癌模型的抑制作用。
采用逆转录病毒介导法将人内皮抑素基因转染至人肺腺癌A549细胞，获得A549/Endo细胞。将A549和A549/Endo细胞分别接种于裸鼠体内（每组10只）。然后，评估每组（n = 5）肿瘤大小的变化及其生长抑制率。每组（n = 5）接种的肿瘤在接种后第28天接受20 Gy的辐射。3天后再次给予20 Gy辐射。通过用铅屏蔽身体其他部位，将电离辐射严格限制在肿瘤部位。定期测量肿瘤大小。移植后第42天，采用免疫组化方法比较4组移植瘤（A549、A549/Endo、A549 + IR和A549/Endo + IR）的微血管密度（MVD）。
PCR证实内皮抑素基因已插入人肺腺癌A549细胞的基因组DNA中。A549组（7.8±1.6）天与A549/Endo组（12.2±1.7）天的肿瘤形成时间差异有统计学意义（P < 0.05）。移植后第42天，A549组和A549/Endo组的肿瘤大小分别为（927.8±269.2）mm³和（217.5±81.5）mm³（P < 0.01），肿瘤生长抑制率为76.5%。辐射后第14天，A549组和A549/Endo组的肿瘤大小分别为（157.7±49.0）mm³和（4.6±2.9）mm³（P < 0.01）。免疫组化检测结果显示，A549/Endo移植瘤的MVD显著降低[与A549移植瘤相比，为21.62±3.55，而A549移植瘤为35.78±5.67（P < 0.01）]。此外，还显示电离辐射可使A549/Endo移植瘤的MVD从21.62±3.55进一步降低至11.32±2.78（P < 0.01）。
逆转录病毒可高效介导内皮抑素基因转染至腺癌细胞。内皮抑素基因转染可通过直接抑制新生血管形成来抑制移植瘤生长。内皮抑素基因转染与电离辐射治疗联合应用可协同抑制新生血管形成及肺腺癌生长。
