摘要
目的探讨miR-155参与TGF-β1对胃癌微环境中的巨噬细胞分型的调控机制。方法免疫组织化学法检测胃癌组织内M2型巨噬细胞标志物CD163的表达和TGF-β1的表达;定量PCR检测胃癌细胞上清培养佛波酯诱导的巨噬细胞中miR-155的表达水平,并观察将TGF-β1受体阻滞后,胃癌细胞上清对miR-155表达的影响;利用双荧光素酶报告基因实验探讨miR-155对TGF-β1信号通路上的TGF-β1受体Ⅱ的靶向调控作用。结果胃癌组织中CD163、TGF-β1的表达显著高于癌旁组织;胃癌细胞上清作用于佛波酯诱导的巨噬细胞后,巨噬细胞内miR-155表达显著降低,TGF-β1作用于巨噬细胞后,miR-155表达降低,而阻断TGF-β1受体作用后,miR-155的表达回升。佛波酯诱导的巨噬细胞中过表达miR-155可使细胞分泌IL-10减少,IL-12增加。双荧光素酶报告基因实验结果显示miR 155可靶向负调控TGF-β1受体Ⅱ。结论胃癌微环境中的TGF-β1可以降低肿瘤相关巨噬细胞内miR-155的表达,后者具有调节巨噬细胞分型的作用,miR-155可通过调节TGF-β1受体Ⅱ对TGF-β1信号通路进行负反馈调节。
Objective To investigate the mechanisms of TGF-β1 in gastric cancer microenvironment mediated mac- rophage differentiation. Methods Immunohistochemical method was used to detecte the expressions of CD163 and TGF-β1 in gastric cancer tissue and corresponding paracarcinoma tissues; RT-PCR was used to detecte the expressions of miR-155 in phorbol myristate acetate （PMA） induced macrophage cultured in the supernatant of gastric cancer cells and observe the effect of TGF-β1 receptor blocker on the expression of miR-155 ; dual luciferase reporter gene assay was used to verify TGF-β1 receptor Ⅱ as the target of miR-155. Results The expressions of CD163, TGF-β1 in gastric cancer tissues was also higher than those in paracarcinoma tissues ; when cultured in the supernatant of gastric cancer ceils, the expression of miR-155 in PMA induced macrophage was decreased significantly. TGF-β1 could decrease the expression of miR-155 in PMA induced macrophage and TGF-β1 receptor blocker restored the level of miR-155. Overexpression of miR-155 in PMA induced macrophages reduced the secretion of IL-10 and increased the secretion of IL-12. Dual lucifer- ase reporter gene assay showed that miR-155 targeted the 3＇UTR of TGF-β1 receptor Ⅱ and decreased the expression of TGF-β1 receptor Ⅱ. Conclusion Altogether, our data uncover that TGF-β1 in gastric cancer micro-enviroment can decrease the expression of miR-155 in macrophages, which infulence the polarization of macrophage and reversly regulate the TGF-β1 pathway by targeting TGF-β1 receptor Ⅱ.
出处
《胃肠病学和肝病学杂志》
CAS
2016年第11期1217-1220,共4页
Chinese Journal of Gastroenterology and Hepatology
基金
国家自然科学基金(81302041)
江苏省自然科学基金(BK20130454)
江苏省高校自然科学基金(12KJD320007)
