Choi Jinju, Kwak Yoonjin, Park Miree, Jo Jeong Yeon, Kang Jun Hyuk, Myeong-Cherl Kook, Kim Hang-Rae, Kim Gwanghun, Kong Seong-Ho, Park Do-Joong, Lee Hye Seung, Lee Hyuk-Joon, Kim Jung Mogg, Kim Sang Gyun, Yang Han-Kwang, Ryu Ji Kon, Cho Soo-Jeong
Division of Gastroenterology, Department of Internal Medicine and Liver Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea.
Department of Gastroenterology, Seoul National University Bundang Hospital, Seongnam, Republic of Korea.
Exp Mol Med. 2025 May 14. doi: 10.1038/s12276-025-01447-8.
Diffuse-type gastric cancer (DGC), characterized by poorly cohesive cells within fibrotic stroma, is associated with advanced disease and poor prognosis. Here, to identify distinct biomarkers for DGC compared with intestinal-type gastric cancer, we constructed a comprehensive large-scale signaling network using RNA-sequencing data from three genomic databases (The Cancer Genome Atlas, GSE62254 and GSE26253), developed a mathematical model and conducted simulation analyses. For validation, we used tissue microarray blocks of gastric cancers with immunohistochemical staining, single-cell RNA sequencing, primary cultures of cancer-associated fibroblasts (CAFs) and organoids, and a co-culture system involving CAFs and cancer cells. Signaling network analysis identified six differentially activated signaling components across the database, including BIRC5, TTK, NEK2, FHL1, NR2F1 and FBLN5. Among the differentially activated signaling components, high tumoral expression of fibulin-5 protein encoded by FBLN5 correlated with poor overall and disease-specific survival rates in patients with DGC, even after adjusting for the tumor, node, metastases (TNM) stage. Fibulin-5, derived from CAFs within DGC stroma, promoted organoid growth and epithelial-mesenchymal transition (EMT) in DGC cell lines via the cAMP response element-binding protein (CREB) pathway in a CAF co-culture system. FBLN5 knockdown in CAFs reduced the aggressive phenotype of co-cultured DGC cells, while CREB inhibitors reversed EMT. Furthermore, levels of secreted FBLN5 in patient blood samples correlated with its expression in primary tumors. In summary, fibulin-5 secreted by CAFs and interacted with DGC cells promotes EMT and is clinically associated with poor patient outcomes. These findings suggest fibulin-5 as a potential prognostic marker and therapeutic target in patients with DGC.
弥漫型胃癌（DGC）的特征是在纤维化基质中细胞黏附性差，与疾病进展和预后不良相关。在此，为了确定与肠型胃癌相比DGC的独特生物标志物，我们利用来自三个基因组数据库（癌症基因组图谱、GSE62254和GSE26253）的RNA测序数据构建了一个全面的大规模信号网络，开发了一个数学模型并进行了模拟分析。为了进行验证，我们使用了胃癌组织微阵列块进行免疫组织化学染色、单细胞RNA测序、癌相关成纤维细胞（CAF）和类器官的原代培养以及涉及CAF和癌细胞的共培养系统。信号网络分析在整个数据库中确定了六个差异激活的信号成分，包括BIRC5、TTK、NEK2、FHL1、NR2F1和FBLN5。在差异激活的信号成分中，由FBLN5编码的纤连蛋白-5蛋白在肿瘤中的高表达与DGC患者的总生存率和疾病特异性生存率低相关，即使在调整肿瘤、淋巴结、转移（TNM）分期后也是如此。源自DGC基质中CAF的纤连蛋白-5在CAF共培养系统中通过环磷酸腺苷反应元件结合蛋白（CREB）途径促进DGC细胞系中的类器官生长和上皮-间质转化（EMT）。CAF中FBLN5的敲低降低了共培养的DGC细胞的侵袭性表型，而CREB抑制剂逆转了EMT。此外，患者血液样本中分泌的FBLN5水平与其在原发性肿瘤中的表达相关。总之，CAF分泌并与DGC细胞相互作用的纤连蛋白-5促进EMT，并且在临床上与患者不良预后相关。这些发现表明纤连蛋白-5是DGC患者潜在的预后标志物和治疗靶点。
