1
|
Omstead AN, Paskewicz M, Gorbunova A, Zheng P, Salvitti MS, Mansoor R, Reed P, Ballengee S, Wagner PL, Jobe BA, Kelly RJ, Zaidi AH. CSF-1R inhibitor, pexidartinib, sensitizes esophageal adenocarcinoma to PD-1 immune checkpoint blockade in a rat model. Carcinogenesis 2022; 43:842-850. [PMID: 35552655 DOI: 10.1093/carcin/bgac043] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 04/14/2022] [Accepted: 05/10/2022] [Indexed: 11/14/2022] Open
Abstract
Esophageal adenocarcinoma (EAC) is a leading cause of cancer deaths. Pexidartinib, a multi-gene tyrosine kinase inhibitor, through targeting CSF-1R, down modulates macrophage mediated pro-survival tumor signaling. Previously, CSF-1R inhibitors have successfully shown to enhance antitumor activity of PD-1/PD-L1 inhibitors by suppressing tumor immune evasion, in solid tumors. In this study, we investigated the antitumor activity of pexidartinib alone or in combination with blockade of PD-1 in a de novo EAC rat model. Here, we showed limited toxicity with significant tumor shrinkage in pexidartinib treated animals compared to controls, single agent and in combination with a PD-1 inhibitor, AUNP-12. Suppression of CSF-1/CSF-1R axis resulted in enhanced infiltration of CD3+CD8+ T cells with reduced M2 macrophage polarization, in the tumor microenvironment (TME). Endpoint tissue gene expression in pexidartinib treated animals demonstrated upregulation of BAX, Cas3, TNFα, IFNγ and IL6 and downregulation of Ki67, IL13, IL10, TGFβ and Arg1 (p<0.05). Additionally, among the pexidartinib treated animals responders compared to non-responders demonstrated a significant upregulation of pre-treatment CSF-1 gene, confirming that tumor associated macrophage suppression directly translates to clinical benefit. Moreover, a post-treatment serum cytokine assay exhibited similar systemic trends as the gene expression in the TME, depicting increases in pro-inflammatory cytokines and decreases in anti-inflammatory cytokines. In conclusion, our study established a promising combinatorial strategy using a CSF-1R inhibitor to overcome resistance to PD-1/PD-L1 axis blockade in an EAC model, providing the rationale for future clinical strategies.
Collapse
Affiliation(s)
- Ashten N Omstead
- Allegheny Health Network, Allegheny Health Network Cancer Institute, Pittsburgh, PA, USA
| | - Michael Paskewicz
- Allegheny Health Network, Allegheny Health Network Cancer Institute, Pittsburgh, PA, USA
| | - Anastasia Gorbunova
- Allegheny Health Network, Allegheny Health Network Cancer Institute, Pittsburgh, PA, USA
| | - Ping Zheng
- Allegheny Health Network, Allegheny Health Network Cancer Institute, Pittsburgh, PA, USA
| | - Madison S Salvitti
- Allegheny Health Network, Allegheny Health Network Cancer Institute, Pittsburgh, PA, USA
| | - Rubab Mansoor
- Allegheny Health Network, Allegheny Health Network Cancer Institute, Pittsburgh, PA, USA
| | - Payton Reed
- Allegheny Health Network, Allegheny Health Network Cancer Institute, Pittsburgh, PA, USA
| | - Sydne Ballengee
- Allegheny Health Network, Allegheny Health Network Cancer Institute, Pittsburgh, PA, USA
| | - Patrick L Wagner
- Allegheny Health Network, Allegheny Health Network Cancer Institute, Pittsburgh, PA, USA
| | - Blair A Jobe
- Allegheny Health Network, Esophageal Institute, Pittsburgh, PA, USA
| | - Ronan J Kelly
- Baylor University Medical Center at Dallas, Department of Hematology and Oncology, Dallas, TX, USA
| | - Ali H Zaidi
- Allegheny Health Network, Allegheny Health Network Cancer Institute, Pittsburgh, PA, USA
| |
Collapse
|