大黄[庶虫]虫丸抑制趋化因子配体17表达对CT26小鼠结肠癌的影响

Effect of Dahuang Zhechong Pill on Development of Colon Cancer in CT26 Mice by Inhibiting the Expression of CCL17

目的观察大黄[庶虫]虫丸对趋化因子配体17(CCL17)在CT26结肠癌小鼠模型中表达的影响,研究其可能的抗肿瘤作用机制。方法复制CT26结肠癌小鼠模型,将模型小鼠随机分为模型组,大黄[庶虫]虫丸高、中、低剂量组(48、24、12 g·kg^-1·d-1),另设正常组。计算各组小鼠结肠癌的抑瘤率;用流式细胞术和免疫荧光法分别检测外周血、肿瘤归巢淋巴结和肿瘤组织细胞中调节性T细胞(Tregs)百分比,肿瘤组织中CCL17的表达,趋化因子受体4(CCR4)在外周血和肿瘤组织细胞表面的表达百分比和肿瘤组织细胞核转录因子κB(NF-κB)p65的表达。结果大黄[庶虫]虫丸能明显抑制小鼠结肠癌的生长,且呈剂量依赖性;大黄[庶虫]虫丸各剂量组肿瘤组织中Tregs明显减少(P<0.05),肿瘤组织中CCL17的荧光强度明显下降(P<0.05);模型组的CCR4+Tregs百分比和CCL17荧光强度最高,大黄[庶虫]虫丸各剂量组随着用药浓度增加,CCR4+Tregs百分比和CCL17荧光强度均表现为依次降低(P<0.05);大黄[庶虫]虫丸能显著抑制结肠癌细胞NF-κB的活化(P<0.05),NF-κB p65的荧光比例显著降低。结论大黄[庶虫]虫丸可通过减少肿瘤组织中Tregs的聚集,降低肿瘤组织中CCL17的表达,下调CCR4在Treg细胞表面的表达比率,降低结肠癌细胞NF-κB p65在细胞内的表达,从而抑制CT26小鼠结肠癌细胞的生长。

Objective The effect of Dahuang Zhechong pill(DZP)on CCL17 in CT26 colon cancer mice model was investigated, and the possible anti-tumor mechanism and clinical application strategy were explored.Methods CT26 colon cancer mice were divided into three groups randomly:model group,DZP(high,medium and low dose)sub-groups and normal group. Flow cytometry and immunofluorescence were used to detect the following indicators respectively: tumor inhibition rate, the percentage of Tregs in peripheral blood, tumor homing lymph nodes and tumor tissues, the expression of chemokine CCL17 in tumor tissues, the expression ratio of chemokine receptor CCR4 on the surface of peripheral blood and tumor tissues,and the activation of nuclear transcription factor κB(NF-κB)p65 in tumor tissues.ResultsDZP can inhibit tumor growth of colon cancer in mice in a dose-dependent manner.Compared with the tumor bearing group, the local Tregs in tumor tissues of each dose group of DZP were significantly reduced(P<0.05). Compared with the tumor bearing group,the mean fluorescence intensities of CCL17 in tumor tissue in each dose group of DZP were significantly decreased(P<0.05);the changes of CCR4 expression percentage on Tregs surface in each experimental group were consistent with these of CCL17. The percentage of CCR4~+Tregs in the tumor bearing group was the highest,and the percentages of CCR4~+Tregs in each dose group decreased in turn with the increase of drug concentration(P<0.05);the activation of NF-κB in colon cancer cells was significantly inhibited by DZP(P<0.05), and the fluorescence percentage of p65 was significantly reduced.ConclusionDZP can inhibit the aggregation of Tregs,reduce the expression of CCL17 and the expression ratio of CCR4 on the surface of Treg cells,and reduce the expression of NF-κB p65 in colon cancer cells to inhibit the development of colon cancer in CT26 mice.