^(125)I放射性粒子植入联合CIK细胞对人肝癌裸鼠移植瘤生长的抑制作用

Inhibitory effects of ^(125)I radioactive particle implantation combined with CIK cells on the growth of human hepatocellular carcinoma xenografts in nude mice

目的:观察125I放射性粒子组织间植入联合细胞因子诱导的杀伤(cytokine-induced killer,CIK)细胞对人肝癌裸鼠移植瘤生长的抑制效应。方法:取健康人外周血单个核细胞,加入不同的细胞因子促进CIK细胞成熟,流式细胞仪检测CIK细胞表型,CD3+CD56+双阳性细胞达20%以上为达标;用人肝癌细胞株SMMC-7721建立裸鼠皮下移植瘤模型,随机分为125I放射性粒子组(A组)、CIK细胞组(B组)、125I粒子+CIK细胞组(C组),空白对照组(D组),分别加处理因素,每4 d测量各组移植瘤体积,观察它们对裸鼠移植瘤生长的抑制作用。HE染色检测各组移植瘤病理变化,免疫组织化学技术检测各组Ki-67蛋白表达,TUNEL试剂盒检测各组移植瘤原位凋亡。结果:125I粒子放射性粒子植入联合CIK细胞静脉输入可明显抑制人肝癌裸鼠移植瘤的生长,C组瘤体积为(0.42±0.17)cm3,显著小于A组(1.23±0.83)cm3、B组(3.77±1.42)cm3和D组(6.62±0.53)cm3,各组瘤体积有显著性差异(F=155.706,P<0.001);C组抑瘤率为93.71%,显著高于A组(81.33%)和B组(43.06%)。免疫组化染色发现各组移植瘤Ki-67蛋白表达的平均吸光度值分别为:C组(0.481±0.063)、A组(0.592±0.104)、B组(0.669±0.120)、D组(0.797±0.113),差异有统计学意义(F=24.334,P<0.001)。TUNEL法发现:C组凋亡的平均光吸光度值(0.859±0.067),显著高于A组(0.756±0.055)和B组(0.517±0.051),差异有显著统计学意义(F=318.373,P<0.001),联合治疗明显抑制细胞增殖,促进肿瘤细胞凋亡。结论:125I放射性粒子永久植入联合CIK细胞免疫治疗在体内可显著抑制人肝癌裸鼠移植瘤的生长,抑制癌细胞增殖,诱导其凋亡,其疗效优于单一治疗方式,局部内放疗联合细胞免疫治疗可能有协同增效作用,有可能成为肝癌综合治疗的方法之一。

[Abstract]Objective：To observe the inhibitory effects of ^125I interstitial brachytherapy combined with eytokine-induced killer（CIK） cells on the growth of human hepatocellular carcinoma（HCC） xenografts in nude mice. Methods：Peripheral blood mononuclear cells were taken from health people and different cytokines were added to promote the mature of CIK cells. CIK cell phenotype was detected bv flow cytometry;CD3^±CD56^± double positive cells reaching 20% was considered as qualified. BAI,B/c nude mice were transplanted with SMMC-7721 HCC cell to establish tumor model and the mice were divided into ^125I radioactive particle group （group A）, C1K cell group （group B）, ^125I radioactive particle ± CIK cell group（group C） and blank control group（group D）. Treat- ment was given respectively,diameters of tumors in each group were measured every 4 d and inhihitory effects of different treatments on gruwth of HCC xenografts were obset~＇ed. Pathological changes of xenografted tumors were detected by HE staining,histo-pathol- ogy and apoptotic rate of these tumors were examined by TUNEL;expressions of Ki-67 protein were detected by immunohistochemical staining. Results：^125I radioactive particle implantation combined with CIK cells intravenously can significantly inhibit the growth of HCC xenograt^s in nude mice. In group C, tumor volume was （0.42± 0.17） cm3,less than those in group A （1.23 ± 0.83） cm3, group B （3.77 ± 1.42） cm^3 and group D（6.62 ± 0.53） cm3,with significant differences among groups（F=I55.706,P〈0.001）.Inhibition rate in group C was 93.71%,significantly higher than those in group A（81.33%） and group B（43.06%）. Immunohistochemical staining re- vealed that mean absurbance value of Ki-67 protein in each group were：group C （0.481 ± 0.063）, group A（0.592± 0.104）,group B （0.669 ± 0.120）,group 1）（0.797 ±0.113） respectively,with statistically significant differences among groups（F=24.334,P〈0.001 ）. Aceording to the results of TUNEL,apoptotic mean absorbance value in group C was （0.859±0.067）,higher than that in group A （0.756 ± 0.055 ） and group B （0.517 ± 0.051 ） respectively, with statistically significant differences in each group （F=318.373, P〈0.001 ）. Conclusions：Permanently implanted radioactive ^125I particle combined with CIK cells immune therapy can significantly inhibit the growth of HCC xenografts in nude mice,restrain the proliferation of tumor and induce apoptusis in vivo,thus it could become a thera- py for hepatoma.