肿瘤相关性中性粒细胞来源的CCL17介导Treg细胞浸润促进肝癌转移复发的机制研究

最近研究表明肿瘤微环境中浸润的中性粒细胞在肿瘤发生发展过程中起到至关重要的作用。前期工作中，通过趋化因子/细胞因子PCR阵列筛选并证实在肝癌中肿瘤相关性中性粒细胞(TANs)高表达趋化因子CCL17；细胞体外趋化实验证实CCL17是参与TANs趋化Treg细胞，并诱导癌内浸润的关键趋化因子。本课题拟首先通过体外细胞功能试验和体内小鼠肝癌成瘤试验，明确TANs分泌的CCL17在肝癌生长和转移过程中的重要作用；然后应用磷酸化蛋白芯片以及western blot、ELISA检测，分析肝癌微环境诱导TANs分泌CCL17的关键信号通路；最后在肝癌组织样本中进行免疫组织化学和免疫荧光检测，观察TANs、CCL17以及Treg表达和定位的关联性，并对其预后价值进行评价。通过以上研究，明确TANs通过分泌CCL17介导Treg浸润，促进肝癌转移复发的作用机制，为探讨肝癌治疗中新的干预靶点提供依据。

Tumor-associated neutrophils (TANs) play a crucial role in carcinogenesis and cancer progression. We have isolated TANs from Hepatocellular carcinoma (HCC) microenvironment and screened their specific secreted cytokines by using chemokine/cytokine array, and recently found that TANs in the HCC microenvironment have a powerful ability for recruiting T regulatory cells (Treg) in a CCL17 dependent manner. In this study, we firstly plan to identify by in vitro and in vivo study, the key chemokine/cytokine CCL17 inducing Treg recruitment which involved in the metastasis and recurrence of HCC and then explore the molecular mechanism regulated by HCC microenvironment. Finally, using tissue microarrays (TMAs) and immunofluorescence in HCC samples, we will determine the relationship between neutrophils and Treg infiltration, and evaluate their prognostic significance. Through the above research, we will determine the effect and mechanism of TANs in recruiting regulatory T-cells infiltration in the HCC microenvironment, and provide experimental evidence for exploring the new intervention targets on the metastasis and recurrence of HCC.