CD40 Agonists Alter the Pancreatic Cancer Microenvironment by Shifting the Macrophage Phenotype toward M1 and Suppress Human Pancreatic Cancer in Organotypic Slice Cultures

Abstract

Background/Aims: CD40 agonists are thought to generate antitumor effects on pancreatic cancer via macrophages and T cells. We aimed to investigate the role of CD40 agonists in the differentiation of macrophages and treatment of human pancreatic adenocarcinoma.Methods: Immunohistochemistry was performed on paraffin-embedded surgical blocks from patients with pancreatic cancers to evaluate macrophage phenotypes and their relationship with survival. The effects of CD40 agonists on macrophage phenotypes and human pancreatic cancer were evaluated utilizing cell cocultures and organotypic slice cultures.Results: CD163 + (predominant in M2 macrophages) and FOXP3 + (predominant in regulatory T cells) expression levels in the tumors were significantly lower in patients with stage IB pancreatic cancer than in those with stage II or III disease (p=0.002 and p=0.003, respectively). Patients with high CD163 + expression had shorter overall survival than those with low CD163 + expression (p=0.002). In vitro treatment of THP-1 macrophages with a CD40 agonist led to an increase in HLA-DR + (predominant in M1 macrophages) and a decrease in CD163 + expression in THP-1 cells. Cell cocultures showed that CD40 agonists facilitate the suppression of PANC-1 human pancreatic cancer cells by THP-1 macrophages. Organotypic slice cultures showed that CD40 agonists alter the pancreatic cancer microenvironment by shifting the macrophage phenotype toward M1 (increase HLA-DR + and decrease CD163 + expression), decreasing the abundance of regulatory T cells, and increasing tumor cell apoptosis.Conclusions: CD163 is related to advanced human pancreatic cancer stages and shorter overall survival. CD40 agonists alter macrophage phenotype polarization to favor the M1 phenotype and suppress human pancreatic cancer.

Accurate cell type deconvolution in spatial transcriptomics using a batch effect-free strategy

“…5d, e). We observed that most infiltrated spots highly expressed M1’s marker gene, Cd40 26 , while many peripheral spots did not express it at all (Fig. 5f).…”

“…This result suggests that M1 macrophage is more actively recruited into the tumor center rather than being gated by the boundary, like other immune cell types. Since M1s are anti-tumor macrophages 26 , we believe further investigation of their role in human EMT samples is critical to understanding and facilitating treatment.…”

“…4g). In contrast, Cd40, an M1 marker 26 , was significantly activated within the mesenchymal microenvironment (fold change = 146%, p = 5e-4, Wilcoxon rank-sum test) (Fig. 4g).…”

“…This result suggests that M1 macrophage is more actively recruited into the tumor center rather than being gated by the boundary, like other immune cell types. Since M1s are anti-tumor macrophages 26 , we believe further investigation of their role in human EMT samples is critical to understanding and facilitating treatment. We first demonstrated that ReSort significantly improves other reference-based deconvolution methods' accuracy in Pearson's correlation coefficient score and KL divergence.…”

In vivo transfection of cytokine genes into tumor cells using a synthetic vehicle promotes antitumor immune responses in a visceral tumor model

“…1 This limitation is primarily because of the degradation and dysfunction of DCs, 2 resulting from the lack of activators in the tumor microenvironment (TME). Agonists or ligands (L) of CD40 induce maturation, enhance the function of DCs, 3 and elicit the generation of antitumoral M1 macrophages from progenitors or pro-tumoral M2 macrophages. 4 Additionally, interferon gamma (IFNγ) activates an antitumoral immune response mediated by mature DCs.…”