熟地黄多糖诱导肝癌细胞凋亡及对STAT3信号通路的影响

目的 观察熟地黄多糖(RGP)对信号转导及转录活化因子STAT3活性的调控、对凋亡抑制基因生存素Survivin的影响;观察凋亡细胞的形态学变化,探讨其促进细胞凋亡的作用及影响. 方法 将 H22肝癌腹水型瘤株移植于小鼠皮下,50只实体瘤模型小鼠随机分5组,采用不同剂量的RGP(1000,500,250 mg/kg)灌胃给药,环磷酰胺40 mg/kg腹腔注射给药.检测免疫器官指数、巨噬细胞功能及抑瘤率;应用原位末端标记法测定各组肿瘤细胞的凋亡指数,观察形态学改变;采用免疫组织化学法检测瘤体 STAT3及 Survivin 的表达情况;应用Western-blot检测STAT3及Survivin蛋白的表达情况. 结果 RGP作用于 H22肝癌细胞后,高、中、低剂量RGP组的抑瘤率分别为34.76%,45.69% 和30.32%,免疫器官指数(P<0.05)和巨噬细胞功能(P< 0.05)提示RGP可改善机体免疫力.RGP各组的凋亡指数与模型组比较均显著升高,差别均有统计学意义(P<0.01).免疫组织化学结果显示,高、低剂量RGP组的STAT3及Survivin表达水平与模型组比较明显降低(P<0.05),中剂量RGP组的STAT3及Survivin表达水平与模型组比较,差别有统计学意义(P<0.01).Western-blot检测结果表明,中剂量RGP组的STAT3及Survivin蛋白表达与模型组比较,差别有统计学意义(P<0.01). 结论 RGP可促进细胞凋亡,并有一定调节免疫的作用,其机制可能与 RGP 抑制 STAT3信号转导通路、并进一步抑制Survivin等下游靶基因的表达有关.

Effect of Rehmannia Glutinosa Polysaccharide on Apoptosis of Hepatocellular Carcinoma Cells and its Effect on STAT Signal Pathway

Objective To observe the effect of rehmannia glutinosa polysaccharide on STAT 3 activity and the its effect on Survivin and the morphological changes,and to explore its role in promoting apoptosis and its impact. Methods H22 hepatocellular carcinoma was transplanted into mice subcutane-ously. Fifty solid tumor model mice were randomly divided into 5 groups,treated with different doses of RGP(1 000,500,250 mg/kg)ig,cyclophosphamide 40 mg/kg,ip. We studied mice's immune organ in-dex,macrophage function,and inhibition rate. The apoptosis index of tumor cells in each group was de-termined by the method of TUNEL,and the morphological changes were observed. The expression of STAT3 and Survivin in the tumor was detected by immunohistochemistry. The expression of STAT3 and Survivin protein was detected by Western-blot. Results The inhibitory rates of RGP were 34.76%, 45.69%,and 30.32% respectively for the 1 000 mg/kg RGP,500 mg/kg RGP,and 250 mg/kg RGP groups. Immune organ index(P<0.05)and macrophage function(P<0.05)suggested that RGP could improve the immunity of the body. The apoptotic index of RGP group was significantly higher than that of model group(P<0.01). Immunohistochemical results showed that the expression of STAT 3 and Sur-vivin protein in high and low dose group were significantly lower than those in model group(P<0.05). The expression levels of STAT3 and Survivin in medium RGP dose group were significantly lower than that of model group(P<0.01). The results of Western-blot showed that the expression of STAT3 and Survivin protein in medium RGP dose group was significantly different from that of model group (P<0.01). Conclusion RGP can promote cell apoptosis and may to a certain degreeregulate immune function,the mechanism of which may be associated with RGP inhibition of STAT 3 signaling pathway, therefore further inhibit the expression of Survivin and other dow nstream target genes.