Exosome-derived circ-001422 promotes tumor-associated macrophage M2 polarization to accelerate the progression of glioma
Wenpeng Cao, Zhirui Zeng, JianFei Sun, Yunhua Chen, FaGuang Kuang, Shipeng Luo, Jinzhi Lan, Shan Lei
Abstract
Cytokines, tumor cells, and tumor-associated macrophages play crucial roles in the composition of glioma tissue. Studies have demonstrated that certain cytokines can induce M2 polarization of tumor-associated macrophages and contribute to the progression of glioma. Nonetheless, the intricate molecular interactions among cytokines, glioma cells, and tumor-associated macrophages remain largely unexplored. To investigate this cross-talk, a combination of RNA-sequencing, chromatin immunoprecipitation, immunoprecipitation, exosome isolation, and biological experiments were employed. Treatment with IL-6 significantly increased circ-001422 expression in glioma cells. A poorer prognosis was associated with elevated levels of circ-001422 in glioma tissues. Circ-001422 was transcribed directly by STAT3 through binding to its promoter. Circ-001422 exerted cancer-promoting functions when co-cultured with M2 macrophages. Furthermore, glioma cells were found to transfer circ-001422 to macrophages via an exosomal pathway, promoting M2 polarization. Mechanically, circ-001422 interacted with p300, resulting in STAT3 acetylation, thus promoting nuclear localization and transcriptional activity of STAT3/NF-κB and M2 macrophage polarization. In conclusion, glioma cells released exosomes enriched with circ-001422, which in turn induce M2 macrophage polarization by activating the STAT3/NF-κB pathway, thereby enhancing the aggressive characteristics of glioma cells. Targeting circ-001422 may represent a potential therapeutic approach for glioma.