丹参酮ⅡA磺酸钠在结肠癌裸鼠移植瘤模型中增殖及血管生成的实验研究

Anticancer effects and mechanisms of Tanshinon ⅡA sulfonic acid on colon carcinoma cell line HT-29 transplanted subcutaneously in nude mice

目的:探讨丹参酮ⅡA(TanIIA)磺酸钠在结肠癌裸鼠移植瘤模型中的抗癌作用及其对肿瘤血管生成的影响.方法:建立结肠癌裸鼠移植瘤模型,随机分成对照组和低、中、高TanⅡA磺酸钠干预组,每组6只.干预组分别用TanⅡA磺酸钠1,5,10mg/kg,ip;对照组等量生理盐水干预.观察抑瘤率,TUNEL法测凋亡指数,CD34标记观察4组瘤块微血管密度(MVD),免疫组化法检测缺氧诱导因子1α(HIF1α)、血管内皮生长因子(VEGF)、环氧合酶2(COX2)的表达.结果:与对照组相比,3组干预组凋亡指数明显上升(均P<0.05),中剂量组增殖减慢最明显,抑瘤率为(26.0±2.4)%.与对照相比,3组干预组MVD,VEGF表达上调,尤以中高剂量组差异显著(均P<0.05);3组干预组COX2表达与对照组无统计学差异;HIF1α在低剂量组表达略有下调,但未达到统计学差异,中高剂量组表达则有明显上调(P<0.05).结论:TanⅡA体内的抗肿瘤效果在中剂量组中最显著,机制可能与诱导细胞凋亡和上调缺氧诱导因子表达有关.

AIM： To investigate the anticancer effects and the mechanism of Taushinon IIA sulfonic aeid（TASA） on colon carcinoma cell line HT-29 transplanted subcutaneously in nude mice. METHODS： HT-29 human colon cancer cells were grown as xenografts in 24 immunodeficient mice, which were randomly divided into 4 groups. The mice in the observation groups were injected intraperitoneally with TASA at 1 mg/kg （ low dosage ） , 5 mg/kg （ medium dosage ） or 10 mg/kg （ large dosage ） respectively once per day for 2 weeks while the mice in the control group were injected with sodium chloride. All the nude mice were sacrificed 2 weeks later and growth inhibition rates of transplanted tumors were measured by weighing the masses. Apoptosis index was tested by TUNEL assay and microvascular density （MVD） was marked by CD34 staining. The protein expression levels of hypoxia-inducible factor 1 alpha （HIF1α）, vascular endothelial growth factor （VEGF） and cyclooxygenase-2 （ COX2 ） were measured by immunohistochemistry. RESULTS： Compared with that in the control group, the apoptosis index significantly increased in the three observation groups（ all P 〈 0.05 ）. The medium dose TASA suppressed HT-29 cell proliferation and the growth inhibition rate was （26.0± 2.4） %. Compared with those in the control group, MVD and VEGF expressions were＇ up-regulated in the observation groups, especially in the medium and large-dose groups （all P 〈 0.05）. No significant difference was observed in the Cox-2 expression between the 4 groups. HIF1α expression was slightly but not significantly down-regulated in low-dose TASA group, while it was significantly up-regulated in the medium and largedose groups as compared with that in the control group （P 〈 0.05 ）. CONCLUSION： Medium dosage of Tanshinon ⅡA sulfonic acid has some obvious anticancer effect of human colon carcinoma transplanted subcutaneously in nude mice. The probable mechanism may be related with the inducement of apoptosis and the up-regulation of hypoxia-inducible factor 1 alpha of human colon carcinoma.