麦角甾苷调节HIPK2-P53通路对人大肠癌裸鼠移植瘤的治疗作用

Verbascoside exerts therapeutic effects against colorectal cancer xenografts in nude mice via HIPK2-P53 pathway

目的:研究肉苁蓉提取物麦角甾苷对人大肠癌裸鼠移植瘤模型肿瘤生长的作用,及对人大肠癌细胞HIPK2-P53通路的影响,探讨麦角甾苷抑制人大肠癌的作用机制.方法:通过腋下接种人结肠癌HCT-116细胞,建立人大肠癌裸鼠移植瘤模型,随机分为:模型组(生理盐水)、麦角甾苷低[20mg/(kg·d)]、中[40 mg/(kg·d)]、高[80 mg/(kg·d)]剂量组和5-氟尿嘧啶(5-fluorouracil,5-FU)组[1 mg/(kg·d)],经腹腔分别给药0.2mL,连续给药2 wk.2 wk后处死裸鼠,分别检测裸鼠瘤体体积、瘤质量,采用免疫组织化学法检测瘤组织中凋亡相关蛋白同源结构域相互作用蛋白激酶2(homeodomain-interacting protein kinase 2,HIPK2)、P53、Bax和Bcl-2的表达情况.结果:麦角甾苷低、中、高剂量及5-F U对裸鼠瘤体大小抑制率分别为:48.41%、61.04%、63.75%和75.14%,瘤体质量抑制率分别为:42.79%、53.90%、60.99%、66.19%.免疫组织化学结果显示,裸鼠大肠癌肿瘤组织中麦角甾苷低、中、高剂量及5-FU组HIPK2的表达量分别为:4.83±0.62、8.46±0.99、11.90±1.21、13.50±0.94;P53的表达量分别为:14.59±0.90、17.60±1.40、23.10±2.10、22.44±2.05;B a x表达量分别为14.41±0.38、15.84±0.54、26.28±0.55、26.34±2.33;Bcl-2的表达量分别为14.08±1.04、11.93±0.93、7.48±0.86、5.46±0.67.结论:麦角甾苷能够抑制人大肠癌裸鼠移植瘤生长,上调凋亡相关蛋白HIPK2、P53、Bax的表达,下调Bcl-2表达,其抑制大肠癌的作用与促进肿瘤细胞凋亡密切相关.

AIM： To investigate whether verbascoside exerts therapeutic effects against colorectal cancer xenografts in nude mice and the possible role of the HIPK2-P53 pathway in this process.METHODS： An ectopic nude mice model of colorectal cancer was established by subcutaneously inoculating human colorectal carcinoma HCT-116 cells into the armpit of nude mice. The mice were then randomly divided into 5 groups： a model control group, low- [20 mg/（kg？d）], medium- [40 mg/（kg？d）], high-dose verbascoside groups [80 mg/（kg？d）], and a 5-fluorouracil （5-FU） group [1 mg/（kg？d）]. Drugs were injected intraperitoneally for two weeks. Two weeks later, the mice were sacrificed and the tumors were peeled off to measure tumor size and weight. The expression of apoptosis-related proteins HIPK2, P53, Bax, and Bcl-2 in tumor tissues was tested by immunohistochemistry. RESULTS： Compared with the model control group, tumor size decreased by 48.41%, 61.04%, 63.75%, and 75.14% in the low-, medium-, high-dose verbascoside groups and the 5-FU group, respectively, and tumor weight decreased by 42.79%, 53.90%, 60.99%, and 66.19%. The relative expression levels of HIPK2 in tumor tissues were 4.83 ± 0.62, 8.46 ± 0.99, 11.90 ± 1.21 and 13.50 ± 0.94, in the low-, medium-, high-dose verbascoside groups and the 5-FU group, respectively. The corresponding values were 14.59 ± 0.90, 17.60 ± 1.40, 23.10 ± 2.10 and 22.44 ± 2.05 for P53, 14.41 ± 0.38, 15.84 ± 0.54, 26.28 ± 0.55 and 26.34 ± 2.33 for Bax, and 14.08 ± 1.04, 11.93 ± 0.93, 7.48 ± 0.86 and 5.46 ± 0.67 for Bcl-2. CONCLUSION： Verbascoside can inhibit the growth of human colorectal cancer xenografts in mice, up-regulate the expression of HIPK2, P53 and Bax, and down-regulate Bcl-2 expression. The inhibition of colorectal cancer by verbascoside was closely with the promotion of tumor cell apoptosis.