肿瘤相关巨噬细胞调控肿瘤干性在哈族食管癌侵袭转移中的作用机制研究

The incidence and mortality of Kazakh esophageal cancer were significantly higher than those of the national average level, and the 5-years survival rate is only 10%. The poor prognosis was closely related to the early invasion, metastasis, recurrence and chemotherapy resistance of tumor. cancer stem cells (CSCs) is an important factor leading to recurrence, chemotherapy resistance and poor prognosis of tumor. Previous studies have shown that tumor-associated macrophages(TAMs) are closely related to the high aggressiveness and poor prognosis of Kazakh esophageal squamous cell carcinoma(ESCC), it is not clear whether the role of TAMs to Kazakh ESCCs carcinogenesis is achieved through tumor stemness maintenance. Therefore, this project intends to sort out ESCC CSCs. In vitro, ESCCs CSCs were co-cultured with macrophages, using morphological observation, tumor stem cell marker test and cell function to analysis the interaction effects between macrophages and esophageal CSCs on tumor proliferation, apoptosis, migration, invasion and resistance to chemotherapy. At the same time through the TGF-β signal pathway gene expression and intervention, analysis the molecular mechanism of TAMs mediated CSCs in ESCCs invasion and chemotherapy resistance; Combined with the distribution of CSCs in the Kazakh ESCC tissues, and the effects of macrophages on tumor stemness maintenance, tumorigenic ability and tumor metastasis in animal models, comprehensively analysis the molecular mechanism of TAMs mediated CSCs stemness, the invasion, metastasis and resistance to chemotherapy of Kazakh ESCCs.

新疆哈族食管癌发病率及死亡率均明显高于全国平均水平，5年生存率仅为10%，较差预后与食管癌早期浸润、转移、术后复发及化疗耐药关系密切。肿瘤干细胞是导致患者复发、化疗耐药及不良预后的重要因素。前期研究发现肿瘤相关巨噬细胞与哈族食管鳞癌的高侵袭性和不良预后关系密切，巨噬细胞促癌的作用是否通过肿瘤细胞干性调节所实现尚不明确。故本项目拟在体外分选食管鳞癌干细胞与巨噬细胞共培养，通过形态观察、肿瘤干性指标和细胞功能实验分析巨噬细胞与食管鳞癌干细胞的交互作用在肿瘤增殖、凋亡、迁移侵袭及对化疗耐药的影响；同时通过TGF-β 信号通路基因表达及干预，分析肿瘤相关巨噬细胞介导肿瘤干性在食管鳞癌侵袭及化疗耐药的分子机制；结合体内哈族食管鳞癌组织中肿瘤干细胞的分布特征，动物模型中巨噬细胞对食管鳞癌干性维持、成瘤能力和转移的影响；综合分析肿瘤相关巨噬细胞介导肿瘤干性在哈族食管鳞癌侵袭转移及化疗耐药的分子机制。

肿瘤干细胞是导致肿瘤患者复发、化疗耐药及不良预后的重要因素。前期研究发现肿瘤相关巨噬细胞与哈族食管鳞癌的高侵袭性和不良预后关系密切，巨噬细胞促癌的作用是否通过肿瘤细胞干性调节所实现尚不明确。本研究发现M2型肿瘤相关巨噬细胞的分布与食管鳞癌组织中干性标记物存在明显的正相关性。非接触共培养体系中M2型肿瘤相关巨噬细胞促进食管鳞癌细胞干性标记物的上调，同时促进食管鳞癌球体细胞的形成和干性特征的维持。进一步研究发现M2型肿瘤相关巨噬细胞来源的TGF-β1与癌细胞TGF-βR1结合是促进食管鳞癌干性特征的重要环节，结合体外和体内动物实验，通过相应靶点和信号通路的干预发现M2型肿瘤相关巨噬细胞介导TGF-β1-smad2/3信号通路是促进和维持食管鳞癌干性特征的重要因素，同时也是M2型肿瘤相关巨噬细胞介导食管鳞癌浸润、转移和化疗耐药的重要机制之一。为肿瘤微环境巨噬细胞介导临床食管鳞癌的靶向及免疫治疗提供理论基础。