补中益气汤对A549/DDP动物模型实体瘤中耐药相关酶GST和TopoⅡ表达的影响

Effect of Buzhongyiqi decoction on the GST and TopoⅡ expression in A549/DDP lung drug resistance tumor-bearing mice

目的研究补中益气汤对A549/DDP细胞荷瘤小鼠实体瘤中耐药相关酶GST和TopoⅡ表达的影响,探讨补中益气汤的作用机制。方法体外培养A549/DDP细胞,接种健康BALB/c小鼠,荷瘤成功后予补中益气汤治疗,实验分为:荷瘤组,补中益气汤低剂量组及补中益气汤高剂量组。取实体瘤后,利用RT-PCR检测GST和TopoⅡmRNA的表达,免疫组化法检测蛋白表达。结果同荷瘤组相比,高低剂量的补中益气汤均可降低耐药相关酶GST和TopoⅡmRNA表达水平,但补中益气汤高剂量组效果同低剂量组区别不大(>0.05)。同荷瘤组相比,高低剂量的补中益气汤均可降低耐药相关酶GST和TopoⅡ蛋白的表达(<0.05),补中益气汤高剂量组的效果优于补中益气汤低剂量组(<0.05)。结论补中益气汤能下调A549/DDP实体瘤中耐药相关酶GST和TopoⅡ的表达水平。

Objective To study the effect of Buzhongyiqi decoction on the glutathione S-transferase（GST ） and DNA topoisomerase Ⅱ（Topo Ⅱ ） expression in A549/DDP lung drug resistance tumor-bearing mice to explore the possible mechanism of Buzhongyiqi decoction on A549/DDP cells. Methods The A549/DDP cells were inoculated into BALB/c mice subcutaneously to establish tumor-bearing model. The mice were administrated by Buzhongyiqi decoction orally, then the mice were randomized into： Buzhongyiqi decoction lower does group and higher does group. The expression of GST and Topo Ⅱ proteins and mRNA was determined by immunohistoehemistry and RT-PCR respectively. Results Buzhongyiqi decoction could significantly downregulate the expression levels of GST mRNA and Topo Ⅱ mRNA in A549/DDP cells, but with no difference between higher and lower doses groups （ P〉 0.05 ） . Buzhongyiqi decoction could decrease the expression levels of GST and TOpo IIproteins in A549/DDP cells, and much efficient in higher does group than in lower does group. Conclusion Buzhongyiqi decoction could decrease the expression levels of GST and Topo Ⅱ in A549/DDP cells.