舟山眼镜蛇毒及其有效组分体内外抑瘤的作用

Tumor-inhibitory activities of the snake venom and its fractionated components from Naja atra Cantor in vivo and in vitro

目的:观察蛇毒(SV)及其有效组分体内外的抗癌活性,为SV抗肿瘤新药的开发提供实验依据。方法:采用四甲基偶氮唑盐比色法(MTT法)筛查不同浓度(5～20mg/mL)SV及其7种分离组分对人结肠癌细胞株(HCT-8)、人肝癌细胞株(Bel-7402)、人口腔上皮癌细胞株(KB)、人乳腺癌细胞株(MCF-7)的影响;并用小鼠肝癌(H22)动物移植瘤作为实验动物模型,进一步观察SV及其组分Ⅳ(0.01～0.03mg/kg)对瘤重、脾重、外周血白细胞和体质量的影响。结果:SV、Ⅲ2和Ⅳ的肿瘤抑制作用较为明显,三者的浓度在20μg/mL时,对HCT-8、Bel-7402、KB以及MCF-7具有非常显著的抑制作用,对HCT-8的抑制率分别为84.37%、79.39%和85.78%;对Bel-7402的抑制率分别为89.64%、88.13%和92.08%;对KB的抑制率分别为90.08%、91.30%和93.93%;对MCF-7的抑制率分别为89.88%、89.49%和92.33%。腹腔注射10 d后,组分Ⅳ对H22有明显的抑制作用,SV组分Ⅳ3个浓度组的瘤重分别为(0.81±0.20)g、(0.70±0.18)g、(0.61±0.17)g,均明显低于对照组瘤重[(1.19±0.21)g,P<0.05],肿瘤生长抑制率(IR)分别为31.93%、41.17%和48.73%。Ⅳ各剂量组小鼠脾脏指数较对照组增加,白细胞数与对照组相比无明显变化。结论:SV及其7种分离组分均能有效抑制4种人肿瘤细胞株(HCT-8、Bel-7402、KB及MCF-7)的生长,不同的SV分离组分对同一肿瘤细胞抑制作用有差异;不同肿瘤细胞对同一SV分离组分的反应性也不同。SV分离组分Ⅳ对动物移植性肿瘤小鼠肝癌H22有良好的实验疗效。

Objective： To study the tumor-inhibitory activities of snake venom （ SV ） and its fractionated components in vitro and in vivo, and to provide laboratory evidences for developing new anti-cancer preparations of snake venom. Methods： MTT method was used to evaluate the effects of SV （ 5 - 20 mg/mL） and 7 types of its fractionated components on HCT-8, Bel-7402, KB and MCF-7. In hepatoma H22 bearing mice as experimental animal models,the effects of SV and its component Ⅳ（0. 01 - 0.03 mg/kg） on tumor weight, spleen weight, peripheral WBC counts and body weight were evaluated. Results： SV and several of its fractions （ Ⅲ2 and Ⅳ ） showed significant tumor inhibitory activities on HCT-8, Bel-7402, KB and MCF-7 cells. At a level of 20 μg/mL, The inhibition rates（ IR% s） by SV, Ⅲ2 and Ⅳ components were 84.37% ,79.39% and 85.78% ,respectively, in HCT-8 cells; 89. 64% , 88. 13% and 92.08% , respectively, in Bel-7402 cells; 90. 08% , 91. 30% and 93.93 % ,respectively,in KB cells ; 89.88%, 89.49% and 92.33 %, respectively, in MCF-7 ceils. On day 10 after intraperitoneal injection, the SV component IV showed significant inhibition of H22 cells in tumor-bearing mice, as reflected by lower tumor weights [ （0.81 ± 0.20） g, （0.70 ± 0. 18 ） g and （0.61 ± 0. 17 ） g ] in three groups on different doses of SV-IV compared with control group [ （1.19 ± 0.21 ）g; P 〈 0.051. In these groups,the IR% was 31.93% ,41.17% and 48.73% ,respectively. Compared with the control group,the SV-IV treated mice showed increased spleen indexes but unchanged WBC counts. Conclusion： Effective growth inhibition in four types of human tumor cells （ HCT-8, Bel-7402, KB, MCF-7 ） was achieved with SV and its 7 fractionated components. The tumor inhibitory activity on a given type of these tumor cells may vary with different SV fractions, and vice versa. Favorable outcome of tumor inhibition in experimental tumor-bearing mice was noted with the fractionated component Ⅳ of snake venom.