CHI3L1 predicted in malignant entities is associated with glioblastoma immune microenvironment

Effective immunotherapies for patients with glioblastoma (GBM) are urgently needed. Chitinase-3 like-protein-1 (CHI3L1) play important roles in the development of gliomas. However, its role in glioma-related immune responses remains unclear. We aimed to comprehensively investigate its biological features and clinical value in glioma, especially in GBM. Transcriptome, proteome and single-cell RNA-sequencing databases were enrolled in the study. Immunostaining and immunoblotting were performed for validation. CHI3L1 was highly correlated with clinical and molecular features, suggesting that high CHI3L1 expression is more likely to be predicted as malignant entities. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed CHI3L1 closely associated with immune responses and inflammatory activities in GBM. In addition, CHI3L1 also correlated with immune cell infiltration and immune checkpoints. Our study suggests that inhibition of CHI3L1 may help to reduce immunosuppression and overcome immunotherapy resistance, which would be an therapeutic area for the treatment of GBM. •CHI3L1 predicts malignant pathological subtypes of glioma and poor patient prognosis.•CHI3L1 contributes to immunosuppressive microenvironment of GBM.•CHI3L1 positively correlates with inhibitory immune checkpoints in GBM.•CHI3L1 inhibition may reduce immunotherapy resistance, which would be therapeutic areas of great interest for GBM.