GSE157602
RNA-seq analysis of aPD-1 treatment outcomes in IL-34 expressing or not expressing CT26 cell line
Interleukin-34 (IL-34) is an alternative ligand to colony-stimulating factor-1 (CSF-1) for the CSF-1 receptor that acts as a key regulator of monocyte/macrophage lineage. In this study, we show that cancer cells-derived IL-34 mediates resistance to immune checkpoint blockade regardless of CSF-1 existence. In a therapeutic study of a programmed death-1 and cytotoxic T-lymphocyte-associated antigen-4 blocking monoclonal antibody, the expression of IL-34 in tumors was accompanied with limited benefits compared to IL-34 non-expressing tumors in various murine cancer models. Consistent with its immunosuppressive characteristics, the expression of IL-34 in tumors correlates with decreased frequencies of cellular (such as CD8+ and CD4+ T cells) and molecular (including various cytokines and chemokines) effectors at the tumor microenvironment. In addition, IL-34 blockade expands the M1-macrophage population. Then, a neutralizing antibody against IL-34 helped to reverse these effects and improved the therapeutic effects of the immune checkpoint blockade in combinatorial therapeutic models, including a patient-derived xenograft model of primary lung adenocarcinoma. Collectively, we revealed that tumor-derived IL-34 inhibits the efficacy of immune checkpoint blockade and proposed the utility of IL-34 blockade as a new strategy for cancer therapy. Overall design: mRNA profile after aPD-1 treatment of tumors derived from IL-34 expressing or not expressing CT26 cells.