IL-33/ST2信号通路参与食管腺癌发生的机制研究

Esophageal adenocarcinoma (EAC) is a typical disease following chronic inflammatory carcinogenesis, it develops from chronic gastroesophageal reflux disease(GERD) and Barrett esophagus(BE). Chronic reflux cause repeatedly stress and injury to the esophageal epithelial cells. It has been proved that epithelial cell-derived IL-33 modulate the inflammatory tumor microenvironment through its receptor ST2.The role of IL-33/ST2 pathway in the carcinogenesis of EAC has not been investigated. In our early study, we found IL-33 was upregulated in the nucleus of esophageal epithelial cells in gastroesophageal reflux disease and Barrett esophagus, and it related to the maintain and magnification of inflammation. Besides IL-33 was even more highly expressed in the cytoplasmic of EAC cells compared to the adjacent tissue. In in vitro and in vivo study, we found IL-33/ST2 promoted esophageal adenocarcinoma cells proliferation and tumor growth. Based on those results, we propose the hypothesis that IL-33 was upregulated in the process of GERD-BE-EAC, from nucleus to cytoplasm and be released, then act as cytokine to regulate tumor cell function and modulate a protumorogenic microenviroment to promote carcinogenesis of EAC. Therefore based on those primitive study, we will explore the clinical data to prove the expression and secretion alteration of IL-33 in the process from GERD to EAC. Then, we will use in vitrol and in vivo experiment to explore the biological function of IL-33/ST2 in the process of GERD-BE-EAC and its role in the modulation of inflammatory tumor microenvironment. Through this project, we can further clarify the potential application value of IL-33/ST2 for therapy targets of esophageal adenocarcinoma.

食管腺癌（EAC）遵循慢性炎症癌变过程，从胃食管反流（GERD）到Barrett食道（BE）再到EAC，慢性反流造成食道上皮细胞的反复应激及损伤。上皮细胞来源IL-33通过其受体ST2参与炎症肿瘤微环境形成，然而该信号通路在EAC发生中的作用尚未见报道。我们发现IL-33在GERD及BE上皮细胞核中高表达，并与炎症维持相关。在EAC中，IL-33在肿瘤细胞胞浆高表达。细胞及动物实验证实了IL-33通过ST2促进EAC细胞增殖及肿瘤生长。据此提出假说，从GERD-BE-EAC，食道上皮细胞IL-33表达增多，逐渐从核内到胞浆，并释放到细胞外，通过ST2调节自身功能及促肿瘤微环境形成参与EAC的发生。基于此本课题拟通过扩大临床样本量进一步明确IL-33在EAC发生过程中的变化，利用细胞及动物实验明确IL-33/ST2信号通路在EAC发生过程中的生物学功能，探讨其作为食管腺癌治疗靶标的潜在价值。

背景: 食管腺癌（EAC）遵循慢性炎症癌变过程，从胃食管反流（GERD）到Barrett食道（BE）再到EAC，慢性反流造成食道上皮细胞的反复应激及损伤。上皮细胞来源IL-33通过其受体ST2参与炎症肿瘤微环境形成，然而该信号通路在EAC发生中的作用尚未见报道。.主要研究内容: 通过免疫组织化学染色(IHC)技术对人类 EAC 的组织芯片中IL-33的表达进行分析。将空肠与食管吻合，建立大鼠胃十二指肠混合反流模型。采用定量即时聚合酶链式反应(RT-qPCR)、免疫印迹(WB)、IHC和酶联免疫吸附试验(ELISA)检测食管腺癌大鼠模型中IL-33的表达。使用食管腺癌细胞(OE19、OE33)和人正常食管上皮细胞(HEEC)进行体外细胞实验。.重要结果及关键数据: 在人类 EAC 的组织芯片中发现，细胞质中 IL-33的表达明显高于邻近正常组织。在大鼠模型中，EAC 组 IL-33的表达明显高于对照组，且随病理分期的升高而升高。在体外实验中，OE19和 OE33的 IL-33 mRNA 和蛋白水平显著高于 HEECs。IL33的刺激增强了 OE19和 OE33的增殖，迁移，侵袭和上皮-间质转化(EMT) ，但可溶性 ST2(sST2)抑制了这些作用。IL-33刺激 OE19和 OE33细胞释放 IL-6。.科学意义：本研究证实了 IL-33在GERD向 EAC 转变过程中的过度表达，并且 IL-33通过 ST2促进 EAC 细胞的致癌作用。IL-33可能是 EAC 的预防靶点。