背景:间变性甲状腺癌(ATC)肿瘤微环境中肿瘤相关巨噬细胞(TAM)的密度与不良预后相关。然而,巨噬细胞和ATC细胞之间的串扰知之甚少。本研究旨在研究巨噬细胞对癌细胞表型的影响。通过蛋白质组学分析,我们发现了M2巨噬细胞和ATC细胞之间的新介质。
方法:巨噬细胞在增殖中的作用,迁移,使用共培养测定和条件培养基(CM)评估ATC细胞的侵袭。使用LC-MS/MS蛋白质组学分析鉴定来自单一或共培养的CM中的分泌因子。我们评估了分泌因子在增殖中的作用,迁移,和癌细胞的入侵。使用体内异种移植模型来评估因子的作用。
结果:M2巨噬细胞显著增加增殖,迁移,和ATC细胞的入侵,而M1巨噬细胞减少了增殖,迁移,和ATC细胞的侵袭。基于CM的蛋白质组学分析,我们确定羧肽酶A4(CPA4)是巨噬细胞和ATC细胞之间串扰的介质。CPA4仅在M2巨噬细胞/8505C的共培养基中检测到,M2巨噬细胞增加了其在癌细胞中的表达。CPA4蛋白在人甲状腺癌中的表达明显增高,特别是在ATCs中,比正常和良性组织。对公开数据的生物信息学分析显示,CPA4表达与甲状腺癌的不良预后和去分化有关。敲除CPA4抑制增殖,菌落形成,迁移,和ATC细胞的入侵,与STAT3、ERK、AKT/mTOR磷酸化和EMT标记表达。此外,M2巨噬细胞刺激导致癌细胞中CPA4表达增加,诱导巨噬细胞向M2表型极化,形成了一个正反馈回路。在CPA4敲低后,异种移植肿瘤没有发展。
结论:我们的数据表明CPA4通过在M2巨噬细胞和ATC细胞之间介导刺激甲状腺癌的进展。CPA4可以成为ATC患者医治的新医治靶点。
Background: The density of tumor-associated macrophages in the tumor microenvironment of anaplastic thyroid cancer (ATC) is associated with poor prognosis. However, the crosstalk between macrophages and ATC cells is poorly understood. This study aimed to examine the impact of macrophages on cancer cell phenotypes. We found a new mediator between M2 macrophages and ATC cells through proteomics analysis. Methods: The role of macrophages in proliferation, migration, and invasion of ATC cells was evaluated using coculture assay and conditioned medium (CM). Secretory factors in the CM from single or coculture were identified using liquid chromatography-tandem mass spectrometry proteomics analysis. We evaluated the role of the secretory factor in proliferation, migration, and invasion of cancer cells. In vivo xenograft model was used to evaluate the effect of the factor. Results: M2 macrophages significantly increased the proliferation, migration, and invasion of ATC cells, whereas M1 macrophages decreased the proliferation, migration, and invasion of ATC cells. Based on proteomic analysis of CM, we identify
carboxypeptidase A4 (CPA4) as a mediator of the crosstalk between macrophages and ATC cells. CPA4 was only detected in the coculture media of M2 macrophage/8505C, and its expression in cancer cells increased by M2 macrophage. The expression of CPA4 protein was significantly higher in human thyroid cancers, particularly in ATCs, than normal and benign tissues. A bioinformatics analysis of public data revealed that CPA4 expression was associated with poor prognosis and dedifferentiation of thyroid cancer. Knockdown of CPA4 suppressed proliferation, colony formation, migration, and invasion of ATC cells, consistent with the decrease of STAT3, ERK, and AKT/mTOR phosphorylation and epithelial-mesenchymal transition (EMT) marker expression. In addition, the increased expression of CPA4 in cancer cells by M2 macrophage stimulation induced the polarization of macrophages to the M2 phenotype, which formed a positive feedback loop. Xenograft tumors did not develop after CPA4 knockdown. Conclusions: Our data suggest that CPA4 stimulates the progression of thyroid cancer by mediating between M2 macrophages and ATC cells. CPA4 can be a new therapeutic target for the treatment of patients with ATC.