放疗干预对宫颈癌荷瘤小鼠的抑瘤作用及对Th1/Th2免疫细胞比例的影响

目的探讨放疗干预对宫颈癌荷瘤小鼠的抑瘤作用及其对辅助性T细胞1(Th1)/Th2细胞比例的影响。方法建立宫颈癌荷瘤小鼠模型,随机分为荷瘤组和放疗组,每组各10只,另设对照组10只。放疗组进行放疗干预14天,荷瘤组和对照组不治疗。放疗后4、6、8、10、12、14天测量肿瘤体积;末次治疗后,ELISA法测定血清干扰素-γ(IFN-γ)、白介素-2(IL-2)、IL-4、IL-10含量;计算抑瘤率、胸腺指数和脾脏指数;HE染色观察肿瘤组织学变化;TUNEL染色观察肿瘤组织细胞凋亡情况;流式细胞术检测脾脏Th1/Th2细胞比例;RT-qPCR和Western blot检测脾脏T盒子转录因子(T-bet)、GATA结合蛋白3(GABA-3)mRNA和蛋白表达。结果与荷瘤组比较,放疗组小鼠4、6、8、10、12、14天肿瘤体积及瘤质量减小,血清IL-2、IFN-γ升高,IL-4、IL-10降低,胸腺指数、脾脏指数升高,Th1细胞比例、Th1/Th2增加,Th2细胞比例减少,T-bet mRNA和蛋白及T-bet/GATA-3表达升高,GATA-3 mRNA和蛋白表达降低(P<0.05)。HE染色显示,荷瘤组肿瘤细胞数量较多,核大深染,无明显坏死;放疗组肿瘤细胞数量减少,出现大量坏死组织。TUNEL染色显示,荷瘤组TUNEL阳性细胞较少,放疗组TUNEL阳性细胞明显增多。结论放疗对宫颈癌荷瘤小鼠具有明显抑瘤作用,可能是通过调节T-bet/GATA-3表达,促进Th1/Th2分化平衡,增强机体免疫功能发挥作用。

Effect of radiotherapy intervention on tumor-bearing mice with cervical cancer and its influence on Th1/Th2 immune cell ratio

Objective To investigate the antitumor effect of radiotherapy intervention on cervical cancer tumor-bearing mice and its effect on the ratio of helper T cell 1(Th1)/Th2 cells.Methods Cervical cancer Hela cells were injected subcutaneously to establish a cervical cancer tumor-bearing mouse model,which was randomly divided into a tumor-bearing group and a radiotherapy group,with 10 mice in each group,and a control group with 10 mice.The radiotherapy group received radiotherapy intervention for 14 days,and the tumor-bearing group and the control group were not treated.Tumor volume was measured at 4,6,8,10,12,and 14 days after treatment.After the last treatment,serum interferon-γ(IFN-γ),interleukin-2(IL-2),IL-4,and IL-10 content were measured by ELISA.The tumor inhibition rate,thymus index and spleen index were calclelated;HE staining was used to observe tumor histological changes,TUNEL staining was used to observe tumor tissue cell apoptosis,flow cytometry was used to detect the ratio of spleen Th1/Th2 cells,RT-qPCR and Western blot were used to detect T-box expressed in T cells(T-bet),GATA binding protein-3(GABA-3)mRNA and protein expression of spleen.Results Compared with the tumor-bearing group,the tumor volume and tumor mass of mice in the radiotherapy group decreased at 4,6,8,10,12,and 14 days,and serum IL-2 and IFN-γlevels increased,and IL-4 and IL-10 levels decreased,thymus index,spleen index increased.Th1 cell ratio,Th1/Th2 increased,Th2 cell ratio decreased,T-bet mRNA and protein expression and T-bet/GATA-3 increased,GATA-3 mRNA and protein expression decreased(P<0.05).HE staining showed the number in the tumor-bearing group was large,nuclei were large and deeply stained,without obvious necrosis,the number in the radiotherapy group were reduced,and a large amount of necrotic tissue appeared.TUNEL staining showed there were fewer TUNEL-positive cells in the tumor-bearing group,and signifi-cantly more in the radiotherapy group.Conclusion Radiotherapy has a significant inhibitory effect on cervical cancer tumorbear-ing mice,which may be through regulating the expression of T-bet/GATA-3,promoting the balance of Th1/Th2 differentiation,and enhancing the immune function of the body to exert its anti-tumor effect.