title: Cross-talk between tumors can affect responses to therapy.
abstract: Advanced stages of cancer often involve multiple tumors in different locations in the body. These tumors are associated with a microenvironment that can influence tumor responses to immunotherapy. Whether tumors and their disparate microenvironment can interact together at distance in a multiple tumor setting, through a form of cross-talk, and affect their responses to immunotherapy has never been described. Our study investigated the cross-talk between two tumors with disparate microenvironments in a mouse model. We demonstrated that immunosuppressive visceral tumors could influence distant subcutaneous (SC) tumors to render them resistant to immunotherapy. We observed distinct modifications in the SC tumor microenvironment following cross-talk with kidney tumors that exhibit a type-2 macrophage-related immunosuppressive microenvironment. Indeed, when a concomitant kidney tumor was present in the mouse, the SC tumors were highly infiltrated with M2 macrophages and had a reduced T cell and NK cell effector immune profile. Finally, blocking the M2-associated chemokine CCL2 or depleting macrophages, significantly improved the effect of immunotherapy on growth of SC tumors in the presence of concomitant kidney tumors. This work emphasizes the potential negative influence that a tumor, with a strong immunosuppressive microenvironment, can exert on distant tumors that would normally be treatment-responsive. This report may lead to a new vision of the prioritization in the treatment of advanced metastatic cancer.
authors.affiliation: Cancer Immunology Research Program; Sir Peter MacCallum Department of Oncology; University of Melbourne ; Parkville, Australia ;
authors.forename: Christel
authors.initials: C
authors.lastname: Devaud
authors.affiliation: Cancer Immunology Research Program; Sir Peter MacCallum Department of Oncology; University of Melbourne ; Parkville, Australia ;
authors.forename: Liza B
authors.initials: LB
authors.lastname: John
authors.affiliation: Cancer Immunology Research Program; Sir Peter MacCallum Department of Oncology; University of Melbourne ; Parkville, Australia ;
authors.forename: Jennifer A
authors.initials: JA
authors.lastname: Westwood
authors.affiliation: Cancer Immunology Research Program; Sir Peter MacCallum Department of Oncology; University of Melbourne ; Parkville, Australia ;
authors.forename: Carmen Sm
authors.initials: CS
authors.lastname: Yong
authors.affiliation: Cancer Immunology Research Program; Sir Peter MacCallum Department of Oncology; University of Melbourne ; Parkville, Australia ;
authors.forename: Paul A
authors.initials: PA
authors.lastname: Beavis
authors.affiliation: Institute of Molecular Cancer Research; University of Zurich ; Zurich, Switzerland ;
authors.forename: Reto A
authors.initials: RA
authors.lastname: Schwendener
authors.affiliation: Cancer Immunology Research Program; Sir Peter MacCallum Department of Oncology; University of Melbourne ; Parkville, Australia ; ; Department of Immunology; Monash University ; Prahran, Victoria, Australia.
authors.forename: Phillip K
authors.initials: PK
authors.lastname: Darcy
authors.affiliation: Cancer Immunology Research Program; Sir Peter MacCallum Department of Oncology; University of Melbourne ; Parkville, Australia ; ; Department of Immunology; Monash University ; Prahran, Victoria, Australia.
authors.forename: Michael H
authors.initials: MH
authors.lastname: Kershaw
keywords: C-C motif ligand-2; CD; CCL2; CD137; CD40; DR5; T cell receptor.; clodronate; cluster of differentiation; IFNγ; immunosuppression; immunotherapy; interferon gamma; IH; interleukin; M2; intrahepatic; IK; intrakidney; IL; natural killer; SC; subcutaneous; TCR; tumor immunology; tumor microenvironment; type 2 macrophages; NK; type-2 macrophages