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Fearon, D. T.

Publications and source records attributed to Fearon, D. T..

2 recordsLinked to original sources

Cancer cell CCR2 orchestrates suppression of the adaptive immune response

C-C chemokine receptor type 2 (CCR2) is expressed on monocytes and facilitates their recruitment to tumors. Though breast cancer cells also express CCR2, its functions in these cells are unclear. We found that Ccr2 deletion in cancer cells led to reduced tumor growth and [~]2-fold longer survival in an orthotopic, isograft breast cancer mouse model. Deletion of Ccr2 in cancer cells resulted in multiple alterations associated with better immune control: increased infiltration and activation of cytotoxic T lymphocytes (CTLs) and CD103+ cross-presenting dendritic cells (DCs), as well as upregulation of MHC class I and downregulation of checkpoint regulator PD-L1 on the cancer cells. Pharmacological or genetic targeting of CCR2 increased cancer cell sensitivity to CTLs and enabled the cancer cells to induce DC maturation toward the CD103+ subtype. Consistently, Ccr2-/- cancer cells did not induce immune suppression in Batf3-/- mice lacking CD103+ DCs. Our results establish that CCR2 signaling in cancer cells can orchestrate suppression of the immune response. SummaryC-C chemokine receptor type 2 (CCR2) expressed on monocytes facilitates their recruitment to tumors. Here, CCR2 signaling in cancer cells is shown to suppress immune control of tumors, in part by reducing CD103+ dendritic cell recruitment.

cancer biology

Endoplasmic reticulum stress engenders immune-resistant, latent pancreatic cancer metastases

Patients who have had their primary pancreatic ductal adenocarcinoma (PDA) surgically resected often develop metastatic disease, exemplifying the problem of latent metastases. Livers from patients and mice with PDA contained single, disseminated cancer cells (DCCs) with an unusual phenotype of being cytokeratin-19 (CK19)- and MHC class I (MHCI)-. We created a mouse model to determine how DCCs develop, their relationship to metastatic latency, and the role of immunity. Intra-portal injection of immunogenic PDA cells into pre-immunized mice seeded livers only with single, non-replicating DCCs lacking MHCI and CK19; naive recipients had macro-metastases. Transcriptomic analysis of PDA cells with the DCC phenotype demonstrated an endoplasmic reticulum (ER) stress response. Relieving ER stress with a chemical chaperone, in combination with T cell-depletion, stimulated outgrowth of macro-metastatic lesions containing PDA cells expressing MHCI and CK19. The ER stress response is the cell-autonomous reaction that enables DCCs to escape immunity and establish latent metastases.\n\nOne sentence summaryLatent pancreatic cancer metastases are created when T cells select disseminated cancer cells in which immune resistance and quiescence have been imposed by endoplasmic stress.

immunology