Profiling the effects and mechanisms of immunopotentiator GC on myeloid cells within the tumor microenvironment using single-cell RNA sequencing (scRNAseq)

Investigating myeloid cells' role during cancer therapy is critical to developing novel strategies, as they shape the tumor microenvironment and modulate anti-tumor immune responses. Using single-cell RNA sequencing (scRNAseq), we examined the impact of the immunostimulant N-dihydrogalactochitosan (GC) on myeloid cells within MMTV-PyMT tumors. We discovered unique myeloid cell clusters with varied responses to GC, showing increased proportions of certain cell types, such as G-MDSC, monocytes, and DCs. Importantly, we observed significant upregulation of STING signaling-associated genes, indicative of conventional STING signaling and canonical NFkB signaling activation. Furthermore, our analysis showed an upregulation of proinflammatory cytokines in cDCs, and a significant reduction in M2-like macrophages post-GC treatment. This supports GC's potent immunostimulatory properties, activating key cells within the tumor microenvironment to enhance antitumor immunity.