Epigenetic modulation of neuroblastoma enhances T cell and NK cell immunogenicity by inducing a tumor-cell lineage switch

Abstract

BackgroundImmunotherapy in high-risk neuroblastoma (HR-NBL) does not live up to its full potential due to inadequate (adaptive) immune engagement caused by the extensive immunomodulatory capacity of HR-NBL. We aimed to tackle one of the most notable immunomodulatory processes in neuroblastoma (NBL), absence of major histocompatibility complex class I (MHC-I) surface expression, a process greatly limiting cytotoxic T cell engagement. We and others have previously shown that MHC-I expression can be induced by cytokine-driven immune modulation. Here, we aimed to identify tolerable pharmacological repurposing strategies to upregulate MHC-I expression and therewith enhance T cell immunogenicity in NBL.MethodsDrug repurposing libraries were screened to identify compounds enhancing MHC-I surface expression in NBL cells using high-throughput flow cytometry analyses optimized for adherent cells. The effect of positive hits was confirmed in a panel of NBL cell lines and patient-derived organoids. Compound-treated NBL cell lines and organoids were cocultured with preferentially expressed antigen of melanoma (PRAME)-reactive tumor-specific T cells and healthy-donor natural killer (NK) cells to determine the in vitro effect on T cell and NK cell cytotoxicity. Additional immunomodulatory effects of histone deacetylase inhibitors (HDACi) were identified by transcriptome and translatome analysis of treated organoids.ResultsDrug library screening revealed MHC-I upregulation by inhibitor of apoptosis inhibitor (IAPi)- and HDACi drug classes. The effect of IAPi was limited due to repression of nuclear factor kappa B (NFκB) pathway activity in NBL, while the MHC-I-modulating effect of HDACi was widely translatable to a panel of NBL cell lines and patient-derived organoids. Pretreatment of NBL cells with the HDACi entinostat enhanced the cytotoxic capacity of tumor-specific T cells against NBL in vitro, which coincided with increased expression of additional players regulating T cell cytotoxicity (eg, TAP1/2 and immunoproteasome subunits). Moreover, MICA and MICB, important in NK cell cytotoxicity, were also increased by entinostat exposure. Intriguingly, this increase in immunogenicity was accompanied by a shift toward a more mesenchymal NBL cell lineage.ConclusionsThis study indicates the potential of combining (immuno)therapy with HDACi to enhance both T cell-driven and NKcell-driven immune responses in patients with HR-NBL.

PRMT5 orchestrates EGFR and AKT networks to activate NFκB and promote EMT

“…Further, we identified NFkB as a downstream effector of AKT and EGFR in regulating EMT transcription factors in neuroblastoma. Given the well-documented role of NFkB in inflammation, cell survival, and proliferation, and recent reports of mesenchymal-like neuroblastoma cells displaying an inflammatory state 43, 44 , it is likely that PRMT5-dependent signaling pathways may also influence the tumor microenvironment, potentially impacting immune evasion and therapy resistance. However, since our studies were conducted in immunocompromised models, these results indicate that PRMT5 may be a viable therapeutic target and suggest that disrupting a PRMT5-dependent AKT-EGFR-NFkB signaling networks may be an effective strategy in treating high-risk neuroblastoma.…”

Targeting pediatric cancers via T-cell recognition of the monomorphic MHC class I-related protein MR1

“…697 target cells were preincubated with 50 μg/mL panHLA-ABC blocking antibody (Clone W6/32, Biolegend) for 1 hour. 29 Cells were subsequently cultured with effector cells at an E:T of 10:1 for 5 hours. HLA-A2 restricted Wilms’ Tumor 1 (WT1)-specific T-cells 30 acted as a positive control for MHC-I block.…”

Nebivolol, an antihypertensive agent, has new application in inhibiting melanoma

“…The development of new antineoplastic drugs is confronted with great challenges, including huge investments, time-consuming, and high failure risks [9,10]. Owing to the thorough investigation of both preclinical and clinical properties, discovering existing drugs for new purposes is able to decrease research duration and costs, and has been widely concerned by more and more researchers and enterprises as an effective alternative strategy to accelerate the development of anticancer drugs [11][12][13]. Consequently, 'new tricks for old drugs' offer new insights in the field of anticancer drug development [14,15].…”