Abstract 2600: A human stem cell model of neuroblastoma reveals candidate drivers of tumorigenesis on chromosome 17q

Abstract Background: In neuroblastoma (NB), the most common pediatric extracranial solid tumor, the most frequent genetic abnormality is gain of chromosome 17q (17q+), occurring in >80% of all patient tumors. 17q+, similar to amplification of the oncogene MYCN, is one of the hallmarks of high-risk NB, which has a 5-year survival rate of less than 50% and is associated with a high relapse rate. Although MYCN-driven mouse models of NB exist, mouse models incorporating human 17q+ cannot be established due to the misalignment of genes on mouse and human chromosomes. Thus, the mechanism by which 17q+ contributes to poor prognosis remains largely unknown. Methods: Here, we used a human stem cell model of NB to investigate the effects of 17q+. Two human embryonic stem cell lines (H7 and H9), either wild-type (WT) or with spontaneous 17q+, were transduced with doxycycline-inducible MYCN, differentiated into sympathoadrenal cells (NB cell of origin), and implanted orthotopically into the renal capsule of immunocompromised mice fed doxycycline chow. RNA sequencing was performed on the resulting MYCN/17q+ and MYCN-driven NBs. In vitro proliferation of the tumor cells was assessed by Incucyte live-cell imaging and EdU incorporation assays. Results: Although 17q+ alone was insufficient to generate NB tumors, MYCN/17q+ tumors compared to MYCN-only tumors exhibited higher penetrance (H7: 100% vs 60%; H9: 100% vs 50% at day 104 post-implantation) and shorter latency (median survival H7: 70 vs 90 days, p=0.0186; H9: 69 vs 114 days, p=0.0001, n=10 per arm), suggesting that MYCN and 17q+ cooperate in tumorigenesis. MYCN/17q+ tumor cells also showed increased proliferation and S-phase occupancy relative to MYCN-only tumor cells in vitro. Bulk RNA sequencing revealed an enrichment in the activation of ribosome biogenesis, cell cycle transition, and DNA replication pathways in MYCN/17q+ tumors. Additionally, 16 genes located on 17q were upregulated in MYCN/17q+ tumors compared to MYCN-only tumors, as well as in NB patients with 17q+ compared to 17q WT. We confirmed the protein-level overexpression of 6 of these 16 genes in MYCN/17q+ tumors: BRIP1 (helicase), TK1 (thymidine kinase), BIRC5 (survivin), and CDC6 (pre-replication complex subunit) directly regulate the cell cycle, while IGF2BP1 (mRNA binding protein) stabilizes the MYCN transcript, and CBX2 (polycomb repressive complex subunit) blocks neural differentiation. Indeed, individual knockdown of these 6 genes in MYCN/17q+ tumor cells reduced proliferation, and individual overexpression in MYCN-only tumor cells enhanced proliferation, implicating these genes in tumorigenesis. Conclusion: A newly established human stem cell model of NB identified BRIP1, TK1, BIRC5, CDC6, IGF2BP1, and CBX2 as candidate genes on chromosome 17q that cooperate in NB tumorigenesis. Citation Format: Wanqi Fang, Bo Cheng, Steven J. Pastor, Ivana Barbaric, Anestis Tsakiridis, Tania Porras, Hong-Wei Wu, Chintan Parekh, Shahab Asgharzadeh, John M. Maris, Miller Huang. A human stem cell model of neuroblastoma reveals candidate drivers of tumorigenesis on chromosome 17q [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 2600.