乳腺癌微环境CAF中GPER对肿瘤他莫昔芬耐受的影响与机制

Cancer associated fibroblasts (CAF) significantly contribute to the development and progression of breast cancer via synthesis of growth factors and local estrogens; therefore, the biologic therapy targeting CAF promises an effective strategy in cancer management. Estrogen (G-protein coupled) receptor (GPER), which plays an essential role in tamoxifen resistance of breast cancer, was demonstrated to be active in CAF and correlated with the synthesis of growth factors and estrogens via GPER-mediated transcriptional activation. Accordingly, it was hypothesized that tamoxifen, as an agonist of GPER, would trigger it and up-regulate the expression of target genes including some could facilitate the synthesis of growth factors and estrogens in CAF, inducing tamoxifen resistance in breast cancer cells.In the present program, microarray and bioinformational analysis would utilized to identify the spectrum of target genes and signal pathways activiated by GPER. Protein chips, chemical luminescence assay, western blot et al would be used to evaluate the contribution of GPER to synthesis of growth factors and estrogens as well as its mechanisms. The influence of GPER on cross-talk between CAF and cancer cells and whether it could induce tamoxifen resistance would be explored by co-culture and co-implantation of them in vivo and in vitro respectively. As a potential therapeutic target, the role of GPER would be evaluated in CAF, possibly indicating an alternative approach to target GPER in CAF for endocrine therapy of breast cancer.

乳腺癌微环境肿瘤相关成纤维细胞（CAF）通过合成生长因子和雌激素对肿瘤发生发展起重要作用,靶向CAF成为治疗新策略。前期研究表明:雌激素G蛋白偶联受体（GPER）在CAF中具有受体活性及转录调节作用，与生长因子及雌激素合成密切相关,在他莫西芬(TAM)耐受中扮演重要角色。据此提出TAM激活CAF中GPER，转录调节下游靶基因表达，促进生长因子和雌激素合成，作用于癌细胞,诱导肿瘤TAM耐受。项目拟在明确CAF表达GPER的基础上应用基因芯片技术及生物信息学分析鉴定CAF中GPER的靶基因谱及其介导的信号通路改变；应用蛋白质芯片、化学发光法、免疫印迹等手段探讨GPER对生长因子和雌激素合成的影响与机制；通过共培养、混合成瘤等实验明确GPER介导CAF与癌细胞交互作用对乳腺癌TAM耐受的影响与机制,探讨靶向CAF细胞中GPER的可能性，结果有望为乳腺癌内分泌治疗探明靶向CAF中GPER的新策略。

乳腺癌微环境肿瘤相关成纤维细胞（CAF）通过合成生长因子和雌激素对肿瘤发生发展起重要作用,靶向CAF成为治疗新策略。前期研究表明:雌激素G蛋白偶联受体（GPER）在CAF中具有受体活性及转录调节作用，与生长因子及雌激素合成密切相关,在他莫西芬(TAM)耐受中扮演重要角色。项目成功构建针对GPER的乳腺癌CAF研究模型。结合GPER激动剂TAM，以CCK-8法及流式细胞仪检测明确GPER介导促进CAF增殖和抑制其凋亡的作用。明确了GPER通过GPER/EGFR/ERK通路调控BCAF增殖和雌激素E2的合成。发现CAF细胞质内GPER转位调控cAMP/PKA/CREB/糖酵解轴以赋予肿瘤细胞多药耐药性。发现GPER可介导CAF外分泌HMGB1促进乳腺癌细胞自噬及增殖。