中华眼镜蛇毒膜毒素对荷瘤小鼠S_(180)细胞增殖和Bcl-2表达的影响

Effect of Venom Cytotoxin from Chinese Cobra on Prolifertion of Sarcoma 180 Cells and Expression of Bcl - 2 in Tumor Bearing Mice

目的:探讨蛇毒膜毒素(CTX)对移植性肿瘤的抑制及其对肿瘤细胞Bcl-2表达的影响。方法:选取ICR小鼠48只,随机分为四组,在各组小鼠右腋皮下接种S180肉瘤细胞,3d后各实验组小鼠分别腋下注射CTX0.8 mg/kg、0.4 mg,/kg、0.2 mg/kg各0.1 mL,连续10 d。分析统计荷瘤小鼠的体重变化和肿瘤抑制率,并通过核仁组织区银染技术(AgNOR)和bcl-2蛋白的免疫组化实验,探讨CTX对体内肿瘤细胞生长和增殖的影响。结果:CTX各剂量组荷瘤小鼠的平均瘤重和瘤/体比值与对照组相比显著地减少(P<0.01),并有明显的剂量反应关系;CTX对体内S180肿瘤细胞的核仁形成区有明显的抑制效应,底、中、高剂量组的AgNOR数(3.693、2.578、1.042)均比对照组(x=3.858)明显减少,且随着CTX处理的浓度越大,AgNOR的数目也越少(P<0.05,P<0.001);对照组肿瘤细胞的bcl-2蛋白表达强烈,经CTX处理后,bcl-2蛋白表达减弱或被完全抑制。结论:CTX对荷瘤小鼠体内肿瘤细胞生长的抑制作用,可能是通过抑制rDNA基因的活性和干扰bcl-2蛋白的表达,从而干扰和阻断肿瘤细胞的增殖。

Objective:To explore the effect of cobra cytotoxin on the inhibition of transplanting tumor and the expression of bcl -2 protein in tumor cells. Methods: 48 mice selected and divided into four groups in random were inoculated the Sarcoma 180 tumor cells into the right armpits. After three days,CTX(0. 8 mg/kg,0. 4 mg/kg,0. 2 mg/kg respectively,once per day) was injected 0. 1 mL respectively for 10 days. The animal weight and the inhibiting rate of tumor in vivo were assayed. Argyrophil Nucleolar Organizer Region ( AgNOR ) and bcl - 2 protein immunohistochemistry were used to study the effect of CTX on the growth and proliferation of tumor cells in vivo. Results: The tumor weight and body weight among each groups were decreased significantly as compared with the control(P <0.01) ,and were apparently dose - dependent. The Nucleolar Organizer Region of Sarcoma 180 tumor cells in vivo were obviously inhibited by CTX. Compared with the control group(x =3. 858) ,the number of AgNOR each groups (low, medium and high dose groups were 3. 693,2. 578 , 1. 042 respectively) was decreased significantly. With the increasing of the dose of CTX,the number of AgNOR decreased (P <0. 05 in low dose group and P<0.001 in high dose group). The expression of bcl -2 protein in the control group was more active as compared with the other groups,but was negatively or weakly expressed after treated with CTX. Conclusion: The growth of tumor cells in the mice can be inhibited by CTX, which may disturb and block the cell proliferation by inhibiting the activity of the rDNA gene and disturbing the expression of bcl -2 protein.