201. Dissecting the Stromal Signaling and Regulation of Myeloid Cells and Memory Effector T Cells in Pancreatic Cancer.
- Author
-
Blair AB, Kim VM, Muth ST, Saung MT, Lokker N, Blouw B, Armstrong TD, Jaffee EM, Tsujikawa T, Coussens LM, He J, Burkhart RA, Wolfgang CL, and Zheng L
- Subjects
- Animals, CD8-Positive T-Lymphocytes drug effects, CD8-Positive T-Lymphocytes immunology, CD8-Positive T-Lymphocytes pathology, Cancer Vaccines administration & dosage, Cancer-Associated Fibroblasts drug effects, Cancer-Associated Fibroblasts immunology, Cancer-Associated Fibroblasts pathology, Carcinoma, Pancreatic Ductal drug therapy, Carcinoma, Pancreatic Ductal pathology, Cell Line, Tumor, Cell Movement, Chemokines immunology, Chemokines metabolism, Female, Humans, Immunologic Memory drug effects, Immunosuppression Therapy, Lymphocytes, Tumor-Infiltrating drug effects, Mice, Mice, Inbred C57BL, Mice, Transgenic, Myeloid Cells drug effects, Myeloid Cells pathology, Pancreatic Neoplasms drug therapy, Pancreatic Neoplasms pathology, Signal Transduction, Stromal Cells drug effects, Stromal Cells pathology, Cancer Vaccines immunology, Carcinoma, Pancreatic Ductal immunology, Immunologic Memory immunology, Lymphocytes, Tumor-Infiltrating immunology, Myeloid Cells immunology, Pancreatic Neoplasms immunology, Stromal Cells immunology
- Abstract
Purpose: Myeloid cells are a prominent immunosuppressive component within the stroma of pancreatic ductal adenocarcinoma (PDAC). Previously, targeting myeloid cells has had limited success. Here, we sought to target the myeloid cells through modifying a specific stromal component., Experimental Design: A murine model of metastatic PDAC treated with an irradiated whole-cell PDAC vaccine and PDAC specimens from patients treated with the same type of vaccine were used to assess the immune-modulating effect of stromal hyaluronan (HA) degradation by PEGPH20., Results: Targeting stroma by degrading HA with PEGPH20 in combination with vaccine decreases CXCL12/CXCR4/CCR7 immunosuppressive signaling axis expression in cancer-associated fibroblasts, myeloid, and CD8
+ T cells, respectively. This corresponds with increased CCR7- effector memory T-cell infiltration, an increase in tumor-specific IFNγ, and improved survival. In the stroma of human PDACs treated with the same vaccine, decreased stromal CXCR4 expression significantly correlated with decreased HA and increased cytotoxic activities, suggesting CXCR4 is an important therapeutic target., Conclusions: This study represents the first to dissect signaling cascades following PDAC stroma remodeling via HA depletion, suggesting this not only overcomes a physical barrier for immune cell trafficking, but alters myeloid function leading to downstream selective increases in effector memory T-cell infiltration and antitumor activity., (©2019 American Association for Cancer Research.)- Published
- 2019
- Full Text
- View/download PDF