Abstract B110: β3-adrenergic receptor as a new molecular target in neuroblastoma treatment

Abstract

Abstract Purpose of study: β3-Adrenergic receptor correlation with tumor growth and progression in preclinical and clinical studies in neuroblastoma. Experimental procedures: Knock-out of β3-Adrenergic Receptor (β3-AR) in Neuroblastoma (NB) cell lines using CRISPR-Cas9 technology. In vivo experiment using β3-AR knock-out cells in order to evaluate the tumor growth in mice. RNA Sequencing of tumor masses derived from mice to investigate β3-AR Dependent tumor signaling pathways. Flow Cytometry analysis to observe the expression level of β3- Adrenergic Receptor on circulating tumor cells (CTCs) in peripheral blood and on disseminated tumor cells (DTCs) in bone marrow from NB patients with low-risk and high-risk prognosis. Summary of data: CRISPR/Cas9 technology was performed to obtain ADRB3-/- clones from human and murine NB cell lines. ADRB3-/- knocked-out cells were inoculated in murine models NU-Foxn1nu and A/J mice, showing an absence of tumor growth compared to wild type NB cells. Subsequently, RNA sequencing on tumor masses was performed to investigate β3-AR-dependent tumor signaling pathways. RNA-sequencing analysis showed many pathways were altered. Notably, downregulation of genes involved in epithelial–mesenchymal transition (EMT) pathway and genes involved in cell adhesion were underlined in Knock-out vs control, correlated with the absence of tumor growth. Cytofluorimetric analysis of β3-AR level expression were conducted on circulating tumor cells (CTCs) in peripheral blood and on disseminated tumor cells (DTCs) in bone marrow from NB patients with low-risk and high-risk prognosis to evaluating the expression levels of β3-AR. As expected, most of the high-risk NB patients showed high percentage of β3-AR+ cells among CTCs and DTCs, while the majority of low-risk patients showed lower percentage. Statement of the conclusions: Ours data showed that β3-AR could be a potential target therapy for neuroblastoma treatment. In fact, his deletion results in an absence of tumor growth and progression as demonstrate in mice in vivo experiments. In addition, NB patients with lower β3-AR level, showed a better prognosis . Furter studies should be focused on the pathways related to β3-AR. Moreover, new drugs will be tested in order to normalize the level of β3-AR in NB patients. Citation Format: Rossana Putino, Alessia Boaretto, Gennaro Bruno, Gianluca Mattei, Annalisa Tondo, Claudio Favre, Maura Calvani. β3-adrenergic receptor as a new molecular target in neuroblastoma treatment [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 B110.