Abstract LB_C20: A tumor-associated chemokine attracts CCR4-expressing CD4+ cells to foster immune repression and tumor aggressiveness in MYCN-driven neuroblastoma

Abstract

Abstract Neuroblastoma, especially those with aberrant MYCN activation, often harbor an immunosuppressive microenvironment to fuel malignant growth and trigger treatment resistance. Despite this knowledge, there are no effective strategies to tackle this problem. Here we combined analyses of human neuroblastoma with live tracking and functional studies of the tumor microenvironment (TME) in zebrafish. We identified a tumor-associated chemokine (TAC) as a key driver of MYCN-mediated immunosuppression and neuroblastoma aggression. Taking advantage of in vivo zebrafish models of MYCN-driven neuroblastoma that resemble human high-risk disease, we demonstrated that TAC overexpression in zebrafish neural crest cells induces an immunosuppressive TME while promoting rapid tumor onset and progression. We also demonstrated that as early as the premalignant stage, tumor cells secrete TAC to attract CCR4-expressing Cd4+ cells to induce immunosuppression and tumor aggression. In addition, genetically depleting Cd4+ T regulatory cells abolishes the immunorestrictive and pro-tumorigenic effects of TAC. We showed that human MYCN-activated neuroblastoma upregulates and secretes TAC, which is a reliable predictor of poor patient survival. Analysis of primary patient samples demonstrates a strong positive association between MYCN and TAC expression in neuroblastoma cells together with the enrichment of FOXP3+ T cells in the TME. Our work provides the first example that MYCN can activate TAC to allure CD4+ immune cells to the TME and incite immunosuppression, positioning TAC as a potential novel immunotherapeutic target for the treatment of MYCN-driven high-risk neuroblastoma. Citation Format: Xiaodan Qin, Andrew Lam, Xu Zhang, Satyaki Sengupta, J. Bryan Iorgulescu, Sanjukta Das, Zhenwei Zhou, Tao Zuo, Grace K. Meara, Madison Rager, Alexander E. Floru, Hongru Ni, Chinyere Kemet, Divya Veerapaneni, Daniel Kashy, Liang Lin, Kenneth Lloyd, Lauren Kwok, Kaylee S. Smith, Raghavendar T. Nagaraju, Rob Meijers, Craig Ceol, Ching-Ti Liu, Sanda Alexandrescu, Catherine J. Wu, Derin B. Keskin, Rani E. George, Hui Feng. A tumor-associated chemokine attracts CCR4-expressing CD4+ cells to foster immune repression and tumor aggressiveness in MYCN-driven neuroblastoma [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2023 Oct 11-15; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2023;22(12 Suppl):Abstract nr LB_C20.