探讨淫羊藿苷（icariin, ICA）对肝癌细胞H22荷瘤小鼠体内抑瘤作用及其机制。方法： 肝癌细胞株H22右腋皮下接种C57BL/6小鼠，建立小鼠体内荷移植瘤模型。接种H22细胞后24 h,用高、中、低不同剂量（9、4.5、2.25 mg/ml）的ICA和环磷酰胺（cyclophosphamide, Cy）（30 mg/kg）进行局部注射治疗，待荷瘤对照组肿瘤长至1 g左右，各组小鼠称重，处死。留自凝血，取血清检测TNFα；依次取脾脏及肿瘤组织称重；取1/2脾脏和肿瘤组织制成单细胞悬液，剩余的用10%中性甲醛溶液固定，做病理切片和HE染色以及TUNEL实验；脾单细胞悬液用流式细胞术（FACS）检测CD3、CD4、CD8、DX5等抗原分子的表达；肿瘤单细胞悬液用AnnexinV/PI双染检测肿瘤细胞的早期与晚期凋亡情况，同时取适量的瘤细胞用70%乙醇固定以FACS检测肿瘤细胞周期各时相的分布情况。结果： Cy治疗组抑瘤率为67.16%，ICA高、中、低剂量治疗组抑瘤率分别为24.63%、 32.84%、5.22%。 AnnexinV/PI双染结果表明，Cy治疗组与ICA治疗组早期凋亡细胞率均高于荷瘤对照组\[Cy组为（9.11±1.584）%，ICA组为（7.14±1.376）%，荷瘤对照组为（3.6±2.38）%\]。TUNEL结果显示，ICA治疗组凋亡指数为（5.35±0.73）%，显著高于荷瘤对照组中的凋亡指数\[（1.03±1.17）%\]（P<0.01）。正常小鼠血清中未检测到TNFα的存在，而ICA治疗组及Cy治疗组中检测到微量TNFα。病理检测表明，ICA中、高剂量组肿瘤组织中出现较多的灶状及小片状坏死，包膜处及肿瘤边缘可见瘤细胞坏死，包膜及肿瘤组织中可见少量的炎细胞（淋巴细胞与单核细胞）浸润。结论： ICA有显著的抑瘤作用，可能通过促进实体瘤细胞早期凋亡引起肿瘤组织坏死而起作用。

To investigate the in vivo antitumor effects of Icarrin (ICA) on H22bearing mice and the related antitumor mechanisms. Methods: C57BL/6 mice were subcutaneously inoculated with H22 hepatocarcinoma cell line to establish H22bearing mice model. 24 h after the inoculation, H22bearing mice were treated with different doses of ICA (9.0 mg/ml, 4.5 mg/ml, and 2.25 mg/ml) and cyclophosphamide (30 mg/kg). When the tumors in H22bearing mice grew to 1 g, the mice were weighed, sacrificed and their spleens and tumors were harvested. The mice sera were also collected for determination of TNFα. Half of the spleens and tumors were made into singlecell suspensions and the other half was fixed by 10% formaldehyde solution for pathology analysis and TUNEL detection. Flow cytometry technique was used to detect the expression of surface antigens CD3, CD4, CD8, and DX5 in the spleen. Annexin V/PI double staining method was used to analyze the early and late apoptosis of tumor singlecell suspension. 1.0×106 cells were used to analyze the cell cycle of the solid tumor cells by flow cytometry. Results: The tumor inhibition rate of cyclophosphamide was 67.16%(P<0.001), and those of high, medium and lowdose ICA groups were 24.63% （P<0.05）, 32.84% （P<0.01）and 5.22%, respectively. Annexin V/PI double staining results indicated that the early apoptosis rate of tumor cells in cyclophosphamide group and mediumdose ICA group were higher than those in H22bearing group \[Cy (911±1.584)%, ICA (7.14±1.376)%, H22bearing group (3.6±2.38)%\]. TUNEL result showed that apoptosis index in ICAmedium group was significantly higher than that in H22bearing group\[(5.35±0.73)% vs (1.03±117)%, P<0.01\]. No TNFα was detected in normal control mice and only very low level of TNFα was found in ICA treatment group and Cy group. Pathology study showed that there were severe necrosis in tumors of medium and highdose ICA groups, with the necrosis found in the capsule and the margin of tumors. A small number of inflammatory cells (lymphocytes and monocytes) were observed in the capsule of tumor and tumor tissues.Conclusion: ICA can effectively inhibit tumor growth, which is probably through inducing early apoptosis of solid tumor cells and the subsequent tumor tissues necrosis.

国家自然科学基金主任基金资助项目（No.30540041）