IL-17A和G-CSF在炎症相关结肠癌中的作用

The association between IL-17A and G-CSF in murine colitis-associated cancer A

目的探索在小鼠结肠炎相关结肠癌(CAC)发展过程中IL-17A和G-CSF的调控关系。方法采用氧化偶氮甲烷和葡聚糖硫酸钠联合诱导建立CAC动物模型,得到了从结肠炎发展到结肠癌三个阶段的小鼠模型(分别为AD1、AD2、AD3),免疫组化检测各阶段小鼠结直肠部位IL-17A和G-CSF表达;重组小鼠IL-17A体外刺激流式分选得到的结直肠上皮细胞,实时PCR和ELISA方法检测G-CSF基因转录和蛋白表达水平。结果 CAC模型经历了从隐窝病灶—腺瘤—腺癌疾病发展过程,与人CAC病程相似。免疫组化结果显示,IL-17A和G-CSF在CAC小鼠结直肠部位的表达均高于健康对照组;IL-17A作用于小鼠结直肠上皮细胞,G-CSF在处理组转录(10.34±0.8)ng/ml和蛋白表达水平(3.5±0.24)ng/ml的表达均高于对照组转录(0.94±0.04)ng/ml和蛋白水平(0.05±0.008)ng/ml的表达,差异均有统计学意义(P﹤0.001)。结论随着小鼠CAC的发展,IL-17A和G-CSF在结直肠组织中均上调表达,且体外实验证实IL-17A促进了结直肠上皮细胞G-CSF表达。

Objective To investigate the correlation between IL-17A and G-CSF during the development of colitis-as-sociated cancer （CAC）. Method A murine colitis-associated colon cancer （CAC） model was established using azoxy-methane （AOM） and dextran sulfate sodium （DSS）. The three stages from colitis to colon cancer were named as ADl, AD2 and AD3, respectively. The expression of IL-17A and G-CSF in rectum were detected by immunohistochemistry. Re-combinant mouse IL-17A was used to stimulate the colorectal epithelial cells sorted by flow cytometry. The transcription and protein expression level of G-CSF were detected by Real-time PCR and ELISA. Result The CAC mouse model un-derwent a normal development process of mucosa—dysplasia—adenoma—carcinoma, which was similar to the develop-ment of human CAC. Immunohistochemistry results indicated that the expression of IL-17A and G-CSF in CAC model was higher than that in normal mice. After IL-17A stimulation, the level of IL-17A and G-CSF were up-regulated in epi-thelial cells compared with control [（10.34±0.8） ng/ml vs （0.94±0.04） ng/ml] and [（3.5±0.24） ng/ml vs （0.05±0.008） ng/ml], P〈0.001, respectively. These findings were statistically significant. Conclusion IL-17A and G-CSF are up-regulated in colorectal tissue as the murine CAC develops, and it is demonstrated that IL-17A promotes the expression of G-CSF in colorectal epithelial cells.