白细胞介素6／信号转导和转录激活因子3通路在胆酸诱导Apc^min／＋小鼠肠腺瘤癌变中的作用  

Role of interleukin-6/signal transduction and activator of transcription 3 signalling in cholic acid-induced intestinal carcinogenesis in Apc^min/＋ mice

作　　者：王斯南[1] 曹海龙[1] 许梦雀 达彬琳 王伟强[1] 陈雪[1] 鄢芳[1] 王邦茂[1] 

机构地区：[1]天津医科大学总医院消化科,300052

出　　处：《中华消化杂志》2017年第2期101-105,共5页Chinese Journal of Digestion

基　　金：国家自然科学基金（81570478、81470796）;天津市应用基础与前沿技术研究计划（15JCZDJC36600）

摘　　要：目的探讨胆酸对Apcmin/＋小鼠肠道腺瘤癌变的影响及其作用机制。方法将20只Apc^min/＋小鼠分为对照组和胆酸组，每组10只。对照组常规饮食，胆酸组在常规饮食基础上添加0.4%胆酸。给药12周后处死，观察两组肠道肿瘤数目、大小和分布情况。HE染色评价肠道肿瘤病理类型，Ki-67免疫组织化学法评价肿瘤细胞增殖水平。实时荧光定量PCR检测肠道炎性细胞因子IL-1β、IL-6和TNF-α mRNA表达水平。通过免疫组织化学法评价胆酸对IL-6/信号转导和转录激活因子3（IL-6/STAT3）通路的激活情况。蛋白质印迹法进一步验证胆酸刺激对IL-6/STAT3及其下游靶基因细胞周期蛋白的影响。统计学分析采用独立样本t检验。结果与对照组相比，胆酸可显著增加Apc^min/＋小鼠肠道腺瘤数量[（22.80±0.93）个比（33.40 ±1.17 ）个]和Ki-67阳性细胞率[（31.60±2.14）%比（71.20±3.19）%]，差异均有统计学意义（t＝7.11、10.31，P均〈0.01）。胆酸组HE染色未见明显炎性细胞浸润，炎性细胞因子IL-1β、IL-6和TNF-α相对表达量均高于对照组（分别为7.09±1.03比1.09±0.11，2.27±0.19比0.99±0.09，14.70±2.29比1.13±0.10），差异均有统计学意义（t＝5.81、6.11、5.92，P均〈0.01）。在小鼠肠道组织中胆酸可明显上调IL-6和磷酸化的STAT3（Tyr705）的蛋白质表达水平，胆酸刺激永生化结肠上皮细胞系（IMCE）组磷酸化的STAT3（Tyr705）表达水平约是对照组的5倍（5 517.00±81.50比863.50±9.13），细胞周期蛋白表达水平约是对照组的7倍（11 165.00±78.53比2 443.00±45.85），差异均有统计学意义（t＝56.74、95.91，P均〈0.01）。结论胆酸可通过诱导肠道低度炎性反应激活IL-6/STAT3通路，促进肿瘤细胞增殖从而诱导Apc^min/＋小鼠肠腺瘤癌变。Objective To investigate the effect of cholic acid on intestinal carcinogenesis and its possible mechanisms in Ap^min/＋ mice. Methods Twenty Apc^mi/＋ mice were divided into control group and cholic acid group, 10 mice in each group. The mice of control group were fed with regular diet, and the mice of cholic acid group were fed with regular diet and 0.4% cholic acid. All mice were sacrificed after treated for 12 weeks. The number, size and location of intestinal adenomas were observed intwo groups. The pathological type was assessed by hematcxylin-eosin （HE） staining. The level of tumor cell proliferation was detected by Ki-67 immunohistochemistry staining. The expression level of intestinal inflammatory cytokines interleukin （IL）-1β, IL-6 and tumor necrosis factor （TNF）-α were measured by real-time polymerase chain reaction （PCR）. The impact of cholic acid on the activation of IL-6/signal transduetion and activator of transcription3 （STAT 3） signalling was determined by immunohistochemistry. The role of cholie acid on IL-6/STAT3 activation and its downstream gene cyclin D1 was further confirmed by Western blot. Independent sample t test was performed for mean comparison between two samples. Results Compard with that of control group, cholie acid significantly increased the total number of intestinal adenomas in Apc^min/＋ mice （22.80±0.93 vs 33.40± 1.17） and percentage of Ki-67 positive cells （（31.60±2.14） % vs （71.20±3.19）%）, and the differences were statistically significant （t= 7. 11 and 10.31, both P〈0.01 ）. There was no obvious inflammatory cells infiltration in cholic acid group according to HE staining. The relative expression levels of inflammatory cytokines IL-1β, IL-6 and TNF-α were higher than those of control group （7. 09±1.03 vs 1. 09±0.11, 2. 27±0.19 vs 0.99±0.09 and 14. 70±2.29 vs 1.13±0.10, respectively）, and the differences were statistically significant （t=5.81, 6.11 and 5.92, all P〈0.01）. In mice intestinal tissues, cholic

关 键 词：胆酸 肠腺瘤 癌变 白细胞介素6 STAT3 Apc^min/+小鼠 

分 类 号：R735.3[医药卫生—肿瘤]