Dual role of ARPC1B in regulating the network between tumor-associated macrophages and tumor cells in glioblastoma

The tumor microenvironment (TME) plays a critical role in promoting the growth and metastasis of glioblastoma (GBM). Tumor-associated macrophages (TAMs), the most abundant myeloid cells infiltrating in TME, produce proinflammatory cytokines, regulate glioma cell pools, and lead to GBM progression. Understanding the mechanism of GBM-TAMs regulation can help to find new targeted therapeutic strategies against GBM. Based on the CGGA and TCGA GBM cohorts, ARPC1B was defined as the key macrophage-associated gene with prognostic value. Higher ARPC1B expression was associated with progressive malignancy, poor outcomes and TAM infiltration. We demonstrated that macrophage-expressed ARPC1B promoted the migration, invasion, and epithelial-mesenchymal transition of glioma cells. Glioma-intrinsic ARPC1B also maintained the malignant phenotype and promoted macrophage recruitment. Positive feedback signaling between macrophages and glioma cells via ARPC1B was determined to be under control of the IFNγ-IRF2-ARPC1B axis. This study highlights the important role of ARPC1B in GBM malignancy progression and the regulation network between GBM and TAMs, suggesting ARPC1B as a novel biomarker with potential therapeutic implications.