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B Cell C-Maf Signaling Promotes Tumor Progression in Animal Models of Pancreatic Cancer and Melanoma

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Abstract

Background: The role of B cells in antitumor immunity remains controversial, with studies suggesting the protumor and antitumor activity. This controversy may be due to the heterogeneity in B cell populations, as the balance among the subtypes may impact tumor progression. The immunosuppressive regulatory B cells (Breg) release interleukin 10 (IL-10) but only represent a minor population. Additionally, tumor-specific antibodies (Abs) also exhibit antitumor and protumor functions dependent on the Ab isotype. Transcription factor c-Maf has been suggested to contribute to the regulation of IL-10 in Breg, but the role of B cell c-Maf signaling in antitumor immunity and regulating Ab responses remains unknown.

Methods: Conditional B cell c-Maf knockout (KO) and control mice were used to establish a KPC pancreatic cancer model and B16.F10 melanoma model. Tumor progression was evaluated. B cell and T cell phenotypes were determined by flow cytometry, mass cytometry, and cytokine/chemokine profiling. Differentially expressed genes in B cells were examined by using RNA sequencing (RNA-seq). Peripheral blood samples were collected from healthy donors and patients with melanoma for B cell phenotyping.

Results: Compared with B cells from the spleen and lymph nodes (LN), B cells in the pancreas exhibited significantly less follicular phenotype and higher IL-10 production in naïve mice. c-Maf deficiency resulted in a significant reduction of CD9 IL-10-producing Breg in the pancreas. Pancreatic ductal adenocarcinoma (PDAC) progression resulted in the accumulation of circulating B cells with the follicular phenotype and less IL-10 production in the pancreas. Notably, B cell c-Maf deficiency delayed PDAC tumor progression and resulted in proinflammatory B cells. Further, tumor volume reduction and increased effective T cells in the tumor-draining LN were observed in B cell c-Maf KO mice in the B16.F10 melanoma model. RNA-seq analysis of isolated B cells revealed that B cell c-Maf signaling modulates immunoglobulin-associated genes and tumor-specific Ab production. We furthermore demonstrated c-Maf-positive B cell subsets and an increase of IL-10-producing B cells after incubation with IL-4 and CD40L in the peripheral blood of patients with melanoma.

Conclusion: Our study highlights that B cell c-Maf signaling drives tumor progression through the modulation of Breg, inflammatory responses, and tumor-specific Ab responses.

References
1.
Lee K, Spata M, Bayne L, Buza E, Durham A, Allman D . Hif1a Deletion Reveals Pro-Neoplastic Function of B Cells in Pancreatic Neoplasia. Cancer Discov. 2015; 6(3):256-69. PMC: 4783189. DOI: 10.1158/2159-8290.CD-15-0822. View

2.
Fridman W, Petitprez F, Meylan M, Chen T, Sun C, Roumenina L . B cells and cancer: To B or not to B?. J Exp Med. 2021; 218(1). PMC: 7754675. DOI: 10.1084/jem.20200851. View

3.
Romero D . B cells and TLSs facilitate a response to ICI. Nat Rev Clin Oncol. 2020; 17(4):195. DOI: 10.1038/s41571-020-0338-6. View

4.
Ullman N, Burchard P, Dunne R, Linehan D . Immunologic Strategies in Pancreatic Cancer: Making Tumors . J Clin Oncol. 2022; 40(24):2789-2805. PMC: 9390820. DOI: 10.1200/JCO.21.02616. View

5.
Higgins B, McHeyzer-Williams L, McHeyzer-Williams M . Programming Isotype-Specific Plasma Cell Function. Trends Immunol. 2019; 40(4):345-357. PMC: 6481617. DOI: 10.1016/j.it.2019.01.012. View