鼻咽癌相关成纤维细胞调控鼻咽癌远处转移的分子机制研究

The molecular mechanism underlying the distant metastasis of nasopharyngeal carcinoma (NPC) is still unclear. The microenvironment and epithelial-mesenchymal transition (EMT) play pivot roles in it. Cancer associated fibroblasts (CAF) are among the most important cells in matrix of cancer, which has been proved associated with the metastasis and EMT of cancer. We screened the expression levels of CAF-related genes in the metastatic tissues of NPC patients with mRNA microarray and found a serious of genes are high expressed, including pro-inflammatory factor tumor necrosis factor α-induced protein 6(TNFAIP6). The primary NPC CAF has been successfully isolated, and the co-culture system of CAF and NPC was set up. The preliminary experiments indicated that TNFAIP6 can enhance the migration of NPC cells, whereas the invasion, migration and tumorigenic ability of NPC cells co-cultured with supernatant of TNFAIP6-knock-down CAF was inhibited. In this study, we will use the co-culture system of NPC and CAF to investigate the molecular mechanism about NPC CAF on the distant metastasis of NPC by in vivo and in vitro experiments, as well as to verify it in clinical samples. Completion this project will eventually clarify the relationship between CAF and NPC metastasis, the key molecular mechanism of EMT and metastasis of NPC regulated by TNFAIP6 secreted by CAF and the potential target of TNFAIP6, which will provide new therapeutic targets and theoretical basis for NPC metastasis.

鼻咽癌远处转移的分子机制不明。肿瘤微环境及细胞上皮-间充质转化(EMT)在远处转移中起着重要的作用。癌症相关成纤维细胞(CAF)是肿瘤微环境中重要的基质细胞，与转移及EMT密切相关。我们经高通量基因芯片筛选到包括炎性因子TNFAIP6在内的多个CAF相关基因在转移灶中高表达；成功培养了鼻咽癌CAF并建立了鼻咽癌与CAF的共培养体系；发现TNFAIP6在CAF中高表达且能促进鼻咽癌细胞的迁移能力；鼻咽癌细胞与下调TNFAIP6表达的CAF上清共培养后侵袭、迁移及成瘤能力下降。本课题拟采用鼻咽癌与CAF的共培养体系，通过体外细胞实验、体内动物模型及临床样品检测，针对CAF及其分泌的TNFAIP6对鼻咽癌发展和转移的影响展开深入研究，明确CAF与鼻咽癌转移的关系，阐明TNFAIP6调控鼻咽癌EMT和远处转移的分子机制，并鉴定TNFAIP6的作用靶点，为鼻咽癌的防治提供重要药物靶点和理论依据。

肿瘤远处转移是鼻咽癌治疗失败的主要原因，而肿瘤微环境在肿瘤转移过程中起着重要作用。本研究中我们旨在探讨癌相关成纤维细胞分泌的TSG6在鼻咽癌转移中所起作用。首先我们从临床活检组织中提取组织RNA并检测TSG6的RNA表达水平，发现 TSG6的高表达水平患者具有显著差的生存预后。接着我们在成对的高转移-低转移鼻咽癌细胞株中发现TSG6均在高转移细胞中本底表达量较高，同时我们发现癌相关成纤维细胞的表达量显著高于高转移鼻咽癌细胞株的表达量；分别上调低转移细胞的TSG6表达可提高细胞迁移、侵袭能力；分别下调高转移细胞的TSG6表达可减弱细胞迁移、侵袭能力。同时在建立起的癌相关成纤维细胞与鼻咽癌细胞共培养体系中发现，敲降TSG6表达的癌相关成纤维细胞对鼻咽癌细胞的迁移、侵袭能力的影响显著降低。在裸鼠模型中，敲减TSG6表达的鼻咽癌细胞组的远处转移显著少于对照组。在共培养后并混合注射构建的鼻咽癌肺转移模型中，敲减TSG6的癌相关成纤维组的远处转移同样显著少于对照组。进一步分子机制研究的结果显示，癌相关成纤维细胞通过影响鼻咽癌EMT转化从而促进肿瘤远处转移，为鼻咽癌靶向治疗提供科学的理论依据。