Molecular and clinical characterization of CD163 expression via large-scale analysis in glioma.

The expression and function of CD163 in glioma are not fully understood. In this report, we collected totally 1323 glioma samples from the Chinese Glioma Genome Atlas (CGGA) dataset, including 325 RNA-seq data and 301 mRNA microarray data, and 697 glioma samples from The Cancer Genome Atlas (TCGA) dataset to characterize the molecular and clinical features of CD163 in glioma by conducting a large-scale study. We found that CD163 expression was positively associated with the grade of malignancy of glioma. CD163 expression was up-regulated in IDH wild-type glioma and mesenchymal subtype. Gene ontology analysis suggested that CD163-related genes were more involved in immune response and angiogenesis in glioma. Moreover, CD163 showed a positive relationship with stromal and immune cell populations. Kaplan-Meier curves analysis revealed that higher CD163 expression indicated significantly poor survival in glioma and glioblastoma multiforme (GBM). Pearson correlation analysis revealed that CD163 was robustly associated with the immune checkpoints and other macrophage markers. These results demonstrated that CD163 predicts poor prognosis in glioma patients. Additionally, combination of CD163 and immune checkpoints may impair angiogenesis and reverse dysfunctional phenotypes of T cells, which suggest that CD163 may be a promising biomarker and target for immunotherapeutic strategies. Abbreviations: CGGA: Chinese Glioma Genome Atlas; TCGA: The Cancer Genome Atlas; TAMs: Tumor associated macrophages; IDH: isocitrate dehydrogenase; GBM: glioblastoma.