Increased CCL18 expression infers a poor prognosis in glioblastoma multiforme and promotes U-87 MG cell proliferation and migration: A retrospective cohort study

This study aims to investigate the role of C-C Motif Chemokine Ligand 18 (CCL18) in glioblastoma multiforme tissues. Glioblastoma multiforme-related gene expression, clinical parameters, and the corresponding expression data in normal tissues were obtained from The Cancer Genome Atlas database and The Genotype-Tissue Expression database, respectively. The expression levels of CCL18 in 1157 normal tissues, 166 glioblastoma multiforme tissues and its relationship with clinicopathological features were analyzed. The degree of immune infiltration in glioblastoma multiforme tissues was assessed using single sample gene set enrichment analysis algorithm and ESTIMATE algorithm. Gene set enrichment analysis was used to explore the biological processes and pathways that may be regulated by CCL18. Univariate and multivariate Cox regression analysis were used to predict the risk factors affecting the prognosis of glioblastoma multiforme patients. Based on risk factors, nomogram models were constructed. Besides, the expression and roles of CCL18 in glioblastoma multiforme were validated in Clinical Proteomic Tumor Analysis Consortium database, GSE57872 dataset, and in vitro. CCL18 mRNA and protein are highly expressed in glioblastoma multiforme tissues and are closely associated with immune infiltration and prognosis in glioblastoma multiforme patients. CCL18 is involved in regulating multiple neural-, immune-, and tumor-related signaling pathways, and potentially promote proliferation, angiogenesis, migration, and epithelial-mesenchymal transition in glioblastoma multiforme tissues. Moreover, CCL18 promoted cell viability and migration in vitro. CCL18 might be a potential molecular marker for prognosis prediction and targeted therapy in glioblastoma multiforme patients.