AB046. Dual role of POSTN in maintaining glioblastoma stem cells and immune-suppressive microglia in glioblastoma

In conclusion, our study defined POSTN as a key regulator in mediating the molecular crosstalk between GSCs and immune-suppressive Microglia in the tumor microenvironment in GBM. POSTN activates the PI3K/AKT/β-catenin/FOSL1 pathway in an autocrine manner to promote GSC self-renewal and tumor growth. At the same time, POSTN recruits microglia in a paracrine manner and upregulates the expression of CD70 in microglia through the PI3K/AKT/NFκB pathway, thereby promoting the development and function of Treg and generating an immunosuppressive tumor microenvironment. Our findings indicate that targeting the POSTN gene may be a promising approach to ablating GSCs, breaking the immunosuppressive environment and overcoming treatment resistance in GBM.