17-二甲基胺乙基-17-去甲氧基格尔德霉素对人胃癌裸鼠移植瘤血管内皮生长因子表达的抑制作用

目的:观察热休克蛋白90(HSP90)抑制剂17-二甲基胺乙基-17-去甲氧基格尔德霉素(17-DMAG)对人胃癌裸鼠移植瘤生长的影响,探讨17-DMAG对胃癌生长和血管生成的抑制作用。方法:用人胃癌细胞HGC-27接种于裸鼠皮下,建立裸鼠胃癌移植瘤模型;将荷瘤裸鼠随机分为3组,每组8只:17-DMAG组(腹腔注射17-DMAG 25 mg/kg)、5-氟尿嘧啶(5-FU)组(腹腔注射5-FU20 mg/kg)及对照组(腹腔注射生理盐水10mL/kg),4周后测量裸鼠移植瘤的体积及重量,HE染色观察形态学变化,同时采用免疫组化方法检测肿瘤组织中CD31(以阳性细胞数计算肿瘤微血管密度)及血管内皮生长因子(VEGF)的表达,采用Western blotting法检测VEGF的表达。结果:17-DMAG组移植瘤体积为(288.10±23.32)mm3,5-FU组移植瘤体积为(366.37±26.42)mm3,对照组移植瘤体积为(957.66±117.51)mm3,前二者与对照组比较,均差异显著(P0.05)。移植瘤重量与对照组比较,17-DMAG组(0.41±0.02)g明显低于对照组(1.12±0.08)g,P0.05;5-FU组(0.48±0.05)g也明显低于对照组(1.12±0.08)g,P0.05;17-DMAG组和5-FU组抑瘤率分别63%和57%,2组抑瘤率无明显差异。17-DMAG组微血管密度(21.72±1.24)比对照组(37.78±1.68)明显减少,P0.05;5-FU组(36.70±1.51)和对照组(37.78±1.68)之间没有显著差异;17-DMAG组肿瘤组织中VEGF的表达(15.39±4.37)明显低于对照组(36.45±7.45)和5-FU组(26.11±6.26)。结论:热休克蛋白90抑制剂17-DMAG可通过降低胃癌组织中血管内皮细胞生长因子的表达抑制肿瘤新生血管的生成,进而抑制裸鼠移植瘤的生长。

Inhibition of 17-DMAG on VEGF expression in transplanted human gastric cancer in nude mice

AIM: To observe the anti-tumor effects of heat shock protein 90(HSP90) inhibitor 17-dimethylaminoethylamino-17 demethoxygeldanamycin (17-DMAG) on the tumor growth and angiogenesis in implanted gastric cancer nude mouse model. METHODS: Human gastric cancer cell HGC-27 was subcutaneous inoculation into the nude mice to develop a tumor model. Ten days later, 24 mice with implanted tumor were randomly divided into 3 groups: 17-DMAG group (receiving 17-DMAG at dose of 25 mg/kg), control group (treated with NS at dose of 10 mL/kg) and 5-fluorouracil(5-FU) group (treated with 5-FU at dose of 20 mg/kg). Four weeks after treatment, the tumor volume and weight, and the inhibitory rates of tumor growth were evaluated. In the meantime, the expression of CD31 was detected by immunohistochemical staining. The expression of vascular endothelial growth factor (VEGF) was determined by Western blotting. RESULTS: The size of xenografts in 17-DMAG treatment group was (288.10±23.32)mm³, and that in 5-FU treatment group was (366.37±26.42)mm³, both were significantly smaller than that in control group (957.66±117.51)mm³. The tumor weight in 17-DMAG treatment group was (0.41±0.02)g, significantly less than that in control group (1.12±0.08)g. The inhibitory rate of 17-DMAG was 63%. A significant decease of MVD in 17-DMAG group (21.72±1.24) was observed as compared to 5-FU group (36.70±1.51) and control group (37.78±1.68). The expression of VEGF in 17-DMAG group (15.39±4.37) was significantly lower than that in 5-FU group (26.11±6.26) and control group (36.45±7.45). CONCLUSION: HSP90 inhibitor 17-DMAG suppresses the expression of VEGF and the angiogenesis of the gastric cancer to inhibit the tumor growth.