Bi Xiaofei, Zhang Wenjin, Shen Meimei, Wu Guicheng, Fang Chengmei, Gao Jian
Department of Gastroenterology and Hepatology, The Second Affiliated Hospital of Chongqing Medical University, No. 76 Linjiang Road, Yuzhong District, Chongqing, 400010, China.
Chongqing Municipality Clinical Research Center for Endocrinology and Metabolic Diseases, Chongqing University Three Gorges Hospital, Chongqing, 400010, China.
Discov Oncol. 2025 Aug 29;16(1):1655. doi: 10.1007/s12672-025-03326-0.
Colorectal cancer (CRC) is one of the most common gastrointestinal malignancies, with a rising global incidence. Despite advances in diagnosis and treatment, effective biomarkers for early detection and targeted therapy remain limited. β-Klotho (KLB), a co-receptor in the FGF signaling pathway, has been implicated in tumor progression and poor prognosis in several cancers. However, its role in CRC is still poorly understood.
To investigate the function of KLB in CRC, we performed a comprehensive pan-cancer analysis using datasets from TCGA, GTEx, Human Protein Atlas, cBioPortal, UALCAN, and TIMER2.0. Analyses included KLB expression profiles, promoter methylation, genetic alterations, immune checkpoint associations, and immune cell infiltration. Functional enrichment was conducted via GO/KEGG and GSEA. A prognostic model was constructed using biostatistical methods. In vitro and in vivo assays-including CCK-8, colony formation, wound healing, and subcutaneous tumor formation in mice-were conducted to evaluate the biological effects of KLB on CRC cells. Additionally, single-cell RNA sequencing data were analyzed to explore the cell-type-specific expression of KLB within the tumor microenvironment.
KLB expression was significantly downregulated in CRC tissues compared to normal tissues and negatively correlated with TNM stage and overall prognosis. Promoter methylation and somatic mutations were observed in CRC, suggesting epigenetic and genetic regulation of KLB. Functional enrichment revealed that KLB is involved in regulating the cell cycle, chromatin remodeling, and immune responses. The prognostic nomogram based on KLB expression showed improved predictive performance for progression-free interval (C-index = 0.778). Experimentally, KLB overexpression inhibited CRC cell proliferation and migration. Single-cell RNA-seq analysis demonstrated that KLB is primarily expressed in fibroblasts and stromal cells within the CRC tumor microenvironment, implicating its role in intercellular communication and immune modulation through pathways such as MIF and MK signaling.
KLB functions as a potential tumor suppressor in CRC, with diagnostic, prognostic, and therapeutic implications. Its expression in stromal components of the tumor microenvironment suggests a regulatory role in immune response and tumor progression. These findings support KLB as a promising biomarker and therapeutic target for CRC.
结直肠癌（CRC）是最常见的胃肠道恶性肿瘤之一，全球发病率呈上升趋势。尽管在诊断和治疗方面取得了进展，但用于早期检测和靶向治疗的有效生物标志物仍然有限。β-klotho（KLB）是成纤维细胞生长因子（FGF）信号通路中的一种共受体，在几种癌症的肿瘤进展和不良预后中发挥作用。然而，其在结直肠癌中的作用仍知之甚少。
为了研究KLB在结直肠癌中的功能，我们使用来自癌症基因组图谱（TCGA）、基因型组织表达（GTEx）、人类蛋白质图谱、cbioportal、UALCAN和TIMER2.0的数据集进行了全面的泛癌分析。分析包括KLB表达谱、启动子甲基化、基因改变、免疫检查点关联和免疫细胞浸润。通过基因本体论（GO）/京都基因与基因组百科全书（KEGG）和基因集富集分析（GSEA）进行功能富集。使用生物统计学方法构建预后模型。进行体外和体内实验，包括细胞计数试剂盒-8（CCK-8）、集落形成、伤口愈合以及小鼠皮下肿瘤形成实验，以评估KLB对结直肠癌细胞的生物学作用。此外，分析单细胞RNA测序数据，以探索肿瘤微环境中KLB的细胞类型特异性表达。
与正常组织相比，结直肠癌组织中KLB表达显著下调，且与TNM分期和总体预后呈负相关。在结直肠癌中观察到启动子甲基化和体细胞突变，提示KLB的表观遗传和遗传调控。功能富集分析显示，KLB参与调节细胞周期、染色质重塑和免疫反应。基于KLB表达的预后列线图对无进展生存期的预测性能有所提高（C指数=0.778）。实验表明，KLB过表达抑制结直肠癌细胞增殖和迁移。单细胞RNA测序分析表明，KLB主要在结直肠癌肿瘤微环境中的成纤维细胞和基质细胞中表达，提示其通过巨噬细胞迁移抑制因子（MIF）和丝裂原活化蛋白激酶（MK）信号等途径参与细胞间通讯和免疫调节。
KLB在结直肠癌中作为一种潜在的肿瘤抑制因子发挥作用，具有诊断、预后和治疗意义。其在肿瘤微环境基质成分中的表达提示其在免疫反应和肿瘤进展中起调节作用。这些发现支持KLB作为结直肠癌有前景的生物标志物和治疗靶点。
