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bioRxiv2020

Mapping the unique and shared functions of oncogenic KRAS and RIT1 with proteome and transcriptome profiling

Aberrant activation of RAS oncogenes is prevalent in lung adenocarcinoma, with somatic mutation of KRAS occurring in [~]30% of tumors. Recently, we identified somatic mutation of the RAS-family GTPase RIT1 in lung adenocarcinoma, but relatively little is known about the biological pathways regulated by RIT1 and how these relate to the oncogenic KRAS network. Here we present quantitative proteomic and transcriptomic profiles from KRAS-mutant and RIT1-mutant isogenic lung epithelial cells and globally characterize the signaling networks regulated by each oncogene. We find that both mutant KRAS and mutant RIT1 promote S6 kinase, AKT, and RAF/MEK signaling, and promote epithelial-to-mesenchymal transition and immune evasion via HLA protein loss. However, KRAS and RIT1 diverge in regulation of phosphorylation sites on EGFR, USO1, and AHNAK proteins. The majority of the proteome changes are related to altered transcriptional regulation, but a small subset of proteins are differentially regulated by both oncoproteins at the post-transcriptional level, including intermediate filament proteins, metallothioneins, and MHC Class I proteins. These data provide the first global, unbiased characterization of oncogenic RIT1 network and identify the shared and divergent functions of oncogenic RIT1 and KRAS GTPases in lung cancer.

cancer biology↗

bioRxiv2022

Engineered bacteria recruit and orchestrate anti-tumor immunity

Tumors employ multiple mechanisms to actively exclude or suppress adaptive immune cells involved in anti-tumor immunity. Strategies focused on overcoming these immunosuppressive or exclusion signals - through localized delivery of chemokines that directly recruit immune cells into the tumor microenvironment - remain limited due to an inability to target therapeutics specifically to the tumor. Synthetic biology enables engineering of cells and microbes for tumor localized delivery, offering therapeutic candidates previously unavailable using conventional systemic administration techniques. Here, we engineer bacteria to produce and intratumorally release chemokines to attract adaptive immune cells into the tumor environment. Intravenous or intratumoral delivery of bacteria expressing an activating mutant of the human chemokine CXCL16 (hCXCL16K42A) leads to the recruitment of activated T cells within tumors and offers therapeutic benefit in multiple mouse tumor models. Furthermore, we rationally target an additional step in the immune activation cascade - specifically, the presentation of tumor-derived antigens by dendritic cells - using a second engineered bacterial strain expressing CCL20. This combined targeting approach led to the recruitment of type 1 conventional dendritic cells and effectively synergized with hCXCL16K42A-induced T cell recruitment to provide additional therapeutic benefit. In summary, we engineer bacteria to cooperatively recruit and activate both innate and adaptive anti-tumor immune responses, offering a new cancer immunotherapy strategy.

cancer biology↗

bioRxiv2021

Inhibition of PLK1-dependent EBNA2 phosphorylation promotes lymphomagenesis in EBV-infected mice.

While Epstein-Barr virus (EBV) establishes a life-long latent infection in apparently healthy human immunocompetent hosts, immunodeficient individuals are at particular risk to develop lymphoproliferative B cell malignancies caused by EBV. A key EBV protein is the transcription factor EBV nuclear antigen 2 (EBNA2), which initiates B cell proliferation. Here, we combine biochemical, cellular and in vivo experiments demonstrating that the mitotic polo-like kinase 1 (PLK1) binds to EBNA2, phosphorylates its transactivation domain and thereby inhibits its biological activity. EBNA2 mutants that impair PLK1 binding or prevent EBNA2 phosphorylation are gain-of-function mutants. They have enhanced transactivation capacities, accelerate the proliferation of infected B cells and promote the development of monoclonal B cell lymphomas in infected mice. Thus, PLK1 coordinates the activity of EBNA2 to attenuate the risk of tumor incidences in favor of the establishment of latency in the infected but healthy host.

cancer biology↗

bioRxiv2025

TET CpG sequence context specific DNA demeth-ylation shapes progression of IDH-mutant gliomas

BackgroundTreatment decisions in IDH-mutant oligodendrogliomas are shaped by tumor aggressiveness, underscoring the need for objective grading of these malignant brain tumors. Material and MethodsWe collected 302 primary and recurrent resections from oligodendrogliomas and performed Ki-67 staining, proteomics and DNA methylation profiling. Results & conclusionDuring tumor progression, DNA methylation of oligodendrogliomas changed along a continuum. This continuum is linked to increased epigenetic aging, methylation of transcription factors and Ki-67+ cell density, and to large scale DNA demethylation. Demethylation was correlated with CpGs flanking sequences preferred by TET enzymes. We confirmed these findings in previously profiled astrocytomas, indicating IDH-mutant gliomas progress along a shared epigenetic axis. We developed an objective DNA methylation based prognostic continuous grading coefficient (CGC{psi}) that captured these changes and outperformed WHO grading for oligodendrogliomas. Our findings underscore the potential of DNA methylation-based grading to more accurately reflect tumor biology and inform clinical decision-making in IDH-mutant gliomas.

cancer biology↗

bioRxiv2020

Heterogeneity in clone dynamics within and adjacent to intestinal tumours identified by Dre-mediated lineage tracing

Somatic models of tissue pathology commonly utilise induction of gene specific mutations in mice mediated by spatiotemporal regulation of Cre recombinase. Subsequent investigation of the onset and development of disease can be limited by the inability to track changing cellular behaviours over time. Here a lineage tracing approach based on ligand dependent activation of Dre recombinase that can be employed independently of Cre is described. The clonal biology of intestinal epithelium following Cre-mediated stabilisation of {beta}-catenin reveals that within tumours many new clones rapidly become extinct. Surviving clones show accelerated population of tumour glands compared to normal intestinal crypts but in a non-uniform manner indicating that intra-tumour glands follow heterogeneous dynamics. In tumour adjacent epithelium clone sizes are smaller than in the background epithelium as a whole. This suggests a zone of around 5 crypt diameters within which clone expansion is inhibited by tumours and that may facilitate their growth.

cancer biology↗

bioRxiv2025

PTEN deficiency linked to chromosome 10q loss leads to aggressive NF2mutant meningioma biology

While most meningiomas are benign and can be surgically removed, a subset behaves aggressively, recurs quickly, and can ultimately be fatal. Recent work has focused on defining this aggressive group. To better characterize this clinically distinct, high-risk group, we analyzed bulk RNA sequencing (RNA-seq) from human meningiomas using a dimension-reduced reference landscape. We identified an NF2 mutant subtype enriched for chromosome 10q loss and low PTEN expression, both of which were strongly associated with shorter time to recurrence. To directly test causality, we engineered several genetically accurate, immunocompetent in vitro and in vivo mouse models with Pten knockdown or knockout. Across models, Pten loss markedly accelerated YAP1-driven tumorigenesis. Projection of Pten-deficient mouse tumors onto bulk and single-cell RNA-seq datasets from human meningiomas revealed that mouse tumors faithfully recapitulate the transcriptional programs of aggressive NF2 mutant meningiomas and robustly predicted clinical outcomes. Collectively, these findings demonstrate that PTEN loss cooperates with YAP1 activation to drive aggressive NF2 mutant meningioma biology, and that the high fidelity of this model to human disease establishes it as a robust platform for mechanistic investigation and therapeutic testing. More broadly, this work highlights the power of cross-species integration in both validating preclinical models and enhancing the translational relevance and utility of dimension-reduced reference landscapes across diverse disease types. One Sentence SummaryPTEN loss causally drives aggressive NF2 mutant meningiomas, and cross-species integration provides a novel, high-fidelity system to validate preclinical models to human disease.

cancer biology↗

bioRxiv2020

Drug screening linked to molecular profiling identifies novel dependencies in patient-derived primary cultures of paediatric high grade glioma and DIPG

Paediatric high grade glioma and diffuse midline glioma (including DIPG) are comprised of multiple biological and clinical subgroups, the majority of which urgently require novel therapies. Patient-derived in vitro primary cell cultures represent potentially useful tools for mechanistic and preclinical investigation based upon their retention of key features of tumour subgroups under experimental conditions amenable to high-throughput approaches. We present 17 novel primary cultures derived from patients in London, Dublin and Belfast, and together with cultures established or shared from Barcelona, Brisbane, Rome and Stanford, assembled a panel of 52 models under 2D (laminin matrix) and/or 3D (neurospheres) conditions, fully credentialed by phenotypic and molecular comparison to the original tumour sample (methylation BeadArray, panel/exome sequencing, RNAseq). In screening a subset of these against a panel of ~400 approved chemotherapeutics and small molecules, we identified specific dependencies associated with tumour subgroups and/or specific molecular markers. These included MYCN-amplified cells and ATM/DNA-PK inhibitors, and DIPGs with PPM1D activating truncating mutations and inhibitors of MDM2 or PARP1. Specific mutations in PDGFRA were found to confer sensitivity to a range of RTK inhibitors, though not all such mutations conferred sensitivity to targeted agents. Notably, dual PDGFRA/FGFR and downstream pathway MEK inhibitors showed profound effects against both PDGFRA-sensitising mutant and FGFR1-dependent non-brainstem pHGG and DIPG. In total, 85% cells were found to have at least one drug screening hit in short term assays linked to the underlying biology of the patients tumour, providing a rational approach for individualised clinical translation.

cancer biology↗

bioRxiv2022

Automatic grading of cervical biopsies by combining full and self-supervision

In computational pathology, predictive models from Whole Slide Images (WSI) mostly rely on Multiple Instance Learning (MIL), where the WSI are represented as a bag of tiles, each of which is encoded by a Neural Network (NN). Slide-level predictions are then achieved by building models on the agglomeration of these tile encodings. The tile encoding strategy thus plays a key role for such models. Current approaches include the use of encodings trained on unrelated data sources, full supervision or self-supervision. While self-supervised learning (SSL) exploits unlabeled data, it often requires large computational resources to train. On the other end of the spectrum, fully-supervised methods make use of valuable prior knowledge about the data but involve a costly amount of expert time. This paper proposes a framework to reconcile SSL and full supervision, showing that a combination of both provides efficient encodings, both in terms of performance and in terms of biological interpretability. On a recently organized challenge on grading Cervical Biopsies, we show that our mixed supervision scheme reaches high performance (weighted accuracy (WA): 0.945), outperforming both SSL (WA: 0.927) and transfer learning from ImageNet (WA: 0.877). We further shed light upon the internal representations that trigger classification results, providing a method to reveal relevant phenotypic patterns for grading cervical biopsies. We expect that the combination of full and self-supervision is an interesting strategy for many tasks in computational pathology and will be widely adopted by the field.

cancer biology↗

bioRxiv2023

The landscape of drug sensitivity and resistance in sarcoma

Sarcomas are a family of rare malignancies composed of over 100 distinct histological subtypes. The rarity of sarcoma poses significant challenges in conducting clinical trials to identify effective therapies, to the point that many rarer subtypes of sarcoma do not have standard-of-care treatment. Even for established regimens, there can be substantial heterogeneity in responses. Overall, novel, personalized approaches for identifying effective treatments are needed to improve patient out-comes. Patient-derived tumor organoids (PDTOs) are clinically relevant models representative of the physiological behavior of tumors across an array of malignancies. Here, we use PDTOs as a tool to better understand the biology of individual tumors and characterize the landscape of drug resistance and sensitivity in sarcoma. We collected n=194 specimens from n=126 sarcoma patients, spanning 24 distinct subtypes. We characterized PDTOs established from over 120 biopsy, resection, and metastasectomy samples. We leveraged our organoid high-throughput drug screening pipeline to test the efficacy of chemotherapeutics, targeted agents, and combination therapies, with results available within a week from tissue collection. Sarcoma PDTOs showed patient-specific growth characteristics and subtype-specific histopathology. Organoid sensitivity correlated with diagnostic subtype, patient age at diagnosis, lesion type, prior treatment history, and disease trajectory for a subset of the compounds screened. We found 90 biological pathways that were implicated in response to treatment of bone and soft tissue sarcoma organoids. By comparing functional responses of organoids and genetic features of the tumors, we show how PDTO drug screening can provide an orthogonal set of information to facilitate optimal drug selection, avoid ineffective therapies, and mirror patient outcomes in sarcoma. In aggregate, we were able to identify at least one effective FDA-approved or NCCN-recommended regimen for 59% of the specimens tested, providing an estimate of the proportion of immediately actionable information identified through our pipeline. HighlightsO_LIStandardized organoid culture preserve unique sarcoma histopathological features C_LIO_LIDrug screening on patient-derived sarcoma organoids provides sensitivity information that correlates with clinical features and yields actionable information for treatment guidance C_LIO_LIHigh-throughput screenings provide orthogonal information to genetic sequencing C_LIO_LISarcoma organoid response to treatment correlates with patient response to therapy C_LIO_LILarge scale, functional precision medicine programs for rare cancers are feasible within a single institution C_LI

cancer biology↗

bioRxiv2023

Analysis of uveal melanoma scRNA sequencing data identifies neoplastic-immune hybrid cells that exhibit metastatic potential

Uveal melanoma (UM) is the most common non-cutaneous melanoma and is an intraocular malignancy that affects nearly 7,000 individuals per year worldwide. Of these, nearly 50% will progress to metastatic disease for which there are currently no effective therapies. Despite advances in the molecular profiling and metastatic stratification of class 1 and 2 UM tumors, little is known regarding the underlying biology of UM metastasis. Our group has identified a disseminated tumor cell population characterized by co-expression of immune and melanoma proteins, (circulating hybrid cells (CHCs), in patients with UM. Compared to circulating tumor cells, CHCs are detected at an increased prevalence in peripheral blood and can be used as a non-invasive biomarker to predict metastatic progression. To identify mechanisms underlying enhanced hybrid cell dissemination we sought to identify hybrid cells within a primary UM single cell RNA-seq dataset. Using rigorous doublet discrimination approaches, we identified UM hybrids and evaluated their gene expression, predicted ligand-receptor status, and cell-cell communication state in relation to other melanoma and immune cells within the primary tumor. We identified several genes and pathways upregulated in hybrid cells, including those involved in enhancing cell motility and cytoskeleton rearrangement, evading immune detection, and altering cellular metabolism. In addition, we identified that hybrid cells express ligand-receptor signaling pathways implicated in promoting cancer metastasis including IGF1-IGFR1, GAS6-AXL, LGALS9-P4HB, APP-CD74 and CXCL12-CXCR4. These results contribute to our understanding of tumor progression and interactions between tumor cells and immune cells in the UM microenvironment that may promote metastasis.

cancer biology↗

bioRxiv2021

Ultraviolet radiation modulates DNA methylation in melanocytes

Ultraviolet radiation (UVR) is the principal causal factor for melanoma; albeit the underlying mechanisms remain unclear. While the mutagenic properties of UVR are irrefutable, the role of UVR-induced mutations in the initiation of melanoma is controversial which highlights the gap in our knowledge of the initial critical molecular mechanisms of UVR-induced melanomagenesis. To investigate the potential non-mutational mechanisms of UVR-induced melanomagenesis, we studied the role of UVR in modulating DNA methylation changes in melanocytes via next-generation sequencing-based methodologies. Here we show that UVR directly causes stable changes in the DNA methylome and transcriptome, one month after exposure. Genomic features associated with transcription were protected from 5mC alterations whereas CpG sites found in intergenic regions were more likely to be affected. Additionally, the long-term effects of UVR seem to perturb signaling pathways important for melanocyte biology. Interestingly, UVR-sensitive CpG sites were found to be prognostic of overall patient survival and highlighted a subset of CpG sites that may be relevant in melanomagenesis. SignificanceWe report a novel finding that ultraviolet radiation (UVR) induces DNA methylation changes along with stable alterations in gene expression in cultured melanocytes. Our results provide experimental evidence of UVR-induced epigenetic rewiring, which may be implicated in the susceptibility to melanomagenesis, independently of its mutational effects. These findings offer novel insight into the role of UVR in the initiation and pathogenesis of melanoma via a currently underappreciated mechanism.

cancer biology↗

bioRxiv2020

Rapid and direct control of target protein levels with VHL-recruiting dTAG molecules

Chemical biology strategies for directly perturbing protein homeostasis including the degradation tag (dTAG) system provide temporal advantages over genetic approaches and improved selectivity over small molecule inhibitors. We describe dTAGV-1, an exclusively selective VHL-recruiting dTAG molecule, to rapidly degrade FKBP12F36V-tagged proteins. dTAGV-1 overcomes a limitation of previously reported CRBN-recruiting dTAG molecules to degrade recalcitrant oncogenes, supports combination degrader studies and facilitates investigations of protein function in cells and mice.

cancer biology↗

bioRxiv2020

A computational systems biology approach identifies SLUG as a mediator of partial Epithelial-Mesenchymal Transition (EMT)

Epithelial-mesenchymal plasticity comprises of reversible transitions among epithelial, hybrid epithelial/mesenchymal (E/M) and mesenchymal phenotypes, and underlies various aspects of aggressive tumor progression such as metastasis, therapy resistance and immune evasion. The process of cells attaining one or more hybrid E/M phenotypes is termed as partial EMT. Cells in hybrid E/M phenotype(s) can be more aggressive than those in either fully epithelial or mesenchymal state. Thus, identifying regulators of hybrid E/M phenotypes is essential to decipher the rheostats of phenotypic plasticity and consequent accelerators of metastasis. Here, using a computational systems biology approach, we demonstrate that SLUG (SNAIL2) - an EMT-inducing transcription factor - can inhibit cells from undergoing a complete EMT and thus stabilizing them in hybrid E/M phenotype(s). It expands the parametric range enabling the existence of a hybrid E/M phenotype, thereby behaving as a phenotypic stability factor (PSF). Our simulations suggest that this specific property of SLUG emerges from the topology of the regulatory network it forms with other key regulators of epithelial-mesenchymal plasticity. Clinical data suggests that SLUG associates with worse patient prognosis across multiple carcinomas. Together, our results indicate that SLUG can stabilize hybrid E/M phenotype(s).

cancer biology↗

bioRxiv2021

Glioblastoma embryonic-like stem cells exhibit immune-evasive phenotype

Glioma stem cells (GSCs) are a subset of cells with self-renewal and tumor-initiating capacities that are thought to participate in drug resistance and immune evasion mechanisms in glioblastoma (GBM). Given GBM heterogeneity, we hypothesized that GSCs might also display cellular hierarchies associated with different degrees of stemness. We evaluated a single-cell RNA-seq glioblastoma dataset (n = 28) and identified a stem cell population co-expressing high levels of embryonic pluripotency markers, named core glioma stem cells (c-GSCs). This embryonic-like population represents 4.22% {+/-} 0.59 of the tumor cell mass, and pathway analysis revealed an upregulation of stemness and downregulation of immune-associated pathways. Using induced pluripotent stem cell technology, we generated an in vitro model of c-GSCs by reprogramming glioblastoma patient-derived cells into induced c-GSCs (ic-GSCs). Immunostaining of ic-GSCs showed high expression of embryonic pluripotency markers and downregulation of antigen presentation HLA proteins, mimicking its tumoral counterpart. Transcriptomic analysis revealed a strong agreement of enriched biological pathways between tumor c-GSCs and in vitro ic-GSCs ({kappa} = 0.71). Integration of ic-GSC DNA methylation and gene expression with chromatin state analysis of epigenomic maps (n = 833) indicated that polycomb repressive marks downregulate HLA genes in stem-like phenotype. Together, we identified c-GSCs as a GBM cell population with embryonic signatures and poor immunogenicity. Genome-scale transcriptomic and epigenomic profiling provide a valuable resource for studying immune evasion mechanisms governing c-GSCs and identifying potential therapeutic targets for GBM immunotherapy.

cancer biology↗

bioRxiv2022

SGC-CAMKK2-1: A chemical probe for CAMKK2

The serine/threonine protein kinase calcium/calmodulin-dependent protein kinase kinase 2 (CAMKK2) plays critical roles in a range of biological processes. Despite its importance, only a handful of inhibitors of CAMKK2 have been disclosed. Having a selective small molecule tool to interrogate this kinase will help demonstrate that CAMKK2 inhibition can be therapeutically beneficial. Herein, we disclose SGC-CAMKK2-1, a selective chemical probe that targets CAMKK2.

cancer biology↗

bioRxiv2025

Functional Spatial Mapping of the Tumour Immune Microenvironment In Advanced Melanoma Patients

IntroductionCurrent spatial proteomic approaches quantify immune checkpoint expression but do not directly measure functional receptor/ligand (PD-1/PD-L1) interactions within the tumor immune microenvironment (TiME). Therapeutic antibodies disrupt receptor-ligand interactions and do not target protein abundance. Methods that resolve functional checkpoint interactions provide biologically distinct insight beyond expression-based assays MethodsWe combined computation and quantitative spatial imaging, FuncO:TiME, [Functional Oncology Mapping (FuncOmap)], to map PD-1/PD-L1 interaction states to spatially defined regions of the TiME, in clinically annotated melanoma specimens, collected before and after neoadjuvant immune checkpoint blockade (ICB), ResultsFuncOmap spatially quantified millions of per-pixel PD-1/PD-L1 interactions demonstrated spatial heterogeneity in checkpoint interaction, not reflected by PD-1 expression levels alone. Post-treatment tissues exhibited increased PD-1/PD-L1 interaction states despite no corresponding increase in expression, indicating persistent or augmented functional checkpoint interaction despite therapy. Integration with spatial immune profiling further demonstrated that checkpoint interaction intensity can be contextualized within distinct immune cell populations. ConclusionWe have established the feasibility of spatially resolved functional checkpoint mapping in human melanoma tissues. We demonstrate that receptor-ligand interactions diverge from protein expression patterns. By enabling direct interrogation of functional checkpoint interaction dynamics within intact tissue architecture, FuncO:TiME advances a functional paradigm for studying immune regulation in cancer.

cancer biology↗

bioRxiv2020

A subset of pediatric thalamic gliomas share a distinct DNA methylation profile, H3K27me3 loss and frequent alteration of EGFR

BackgroundMalignant astrocytic gliomas in children show a remarkable biological and clinical diversity. Small in-frame insertions or missense mutations in the EGFR gene have recently been identified in a distinct subset of pediatric bithalamic gliomas with a unique DNA methylation pattern. MethodsHere, we investigated an epigenetically homogeneous cohort of malignant gliomas (n=58) distinct from other subtypes and enriched for pediatric cases and thalamic location, in order to elucidate the overlap with this recently identified subtype of pediatric bithalamic gliomas. ResultsEGFR gene amplification was detected in 16/58 (27%) tumors, and missense mutations or small in-frame insertions in EGFR were found in 20/30 tumors with available sequencing data (67%; five of them co-occurring with EGFR amplification). Additionally, eight of the 30 tumors (27%) harbored an H3.1 or H3.3 K27M mutation (six of them with a concomitant EGFR alteration). All tumors tested showed loss of H3K27me3 staining, with evidence of EZHIP overexpression in the H3 wildtype cases. Although some tumors indeed showed a bithalamic growth pattern, a significant proportion of tumors occurred in the unilateral thalamus or in other (predominantly midline) locations. ConclusionsOur findings present a distinct molecular class of pediatric malignant gliomas largely overlapping with the recently reported bithalamic gliomas characterized by EGFR alteration, but additionally showing a broader spectrum of EGFR alterations and tumor localization. Global H3K27me3 loss in this group appears to be mediated by either H3 K27 mutation or EZHIP overexpression. EGFR inhibition may represent a potential therapeutic strategy in these highly aggressive gliomas. Key pointsO_LIThis study confirms a distinct new subset of pediatric diffuse midline glioma with H3K27me3 loss, with or without H3 K27 mutation C_LIO_LIThe poor outcome of these tumors is in line with the broader family of pediatric diffuse midline gliomas with H3 K27 mutation or EZHIP overexpression C_LIO_LIFrequent EGFR alterations in these tumors may represent a therapeutic target in this subset C_LI Importance of the StudyMalignant astrocytic gliomas in children show a remarkable biological and clinical diversity. Here, we highlight a distinct molecular class of pediatric malignant gliomas characterized by EGFR alteration and global H3K27me3 loss that appears to be mediated by either H3 K27 mutation or EZHIP overexpression. EGFR inhibition may represent a potential therapeutic strategy in these highly aggressive gliomas.

cancer biology↗

bioRxiv2025

The Th1/Th17 axis regulates chimeric antigen receptor (CAR) T cell therapy toxicities

CAR-T therapy has led to significant improvements in patient survival. However, a subset of patients experience high-grade toxicities, including cytokine release syndrome (CRS) and immune cell-associated hematologic toxicity (ICAHT). We utilized IL-2R knockout mice to model cytokine toxicities with elevated levels of IL6, IFN{gamma}, and TNF and increased M1-like macrophages. Onset of CRS was accompanied by a reduction in peripheral blood neutrophils due to disruption of bone marrow neutrophil homeostasis characterized by an increase in apoptotic neutrophils and a decrease in proliferative and mature neutrophils. Both non-tumor-bearing and E-ALL tumor-bearing mice recapitulated the co-occurrence of CRS and neutropenia. IFN{gamma}-blockade alleviated CRS and neutropenia without affecting CAR-T efficacy. Mechanistically, a Th1-Th17 imbalance was observed to drive co-occurrence of CRS and neutropenia in an IFN{gamma}-dependent manner leading to decreased IL-17A and G-CSF, neutrophil production, and neutrophil survival. In patients, we observed an increase in the IFN{gamma}-to-IL-17A ratio in the peripheral blood during high-grade CRS and neutropenia. We have uncovered a biological basis for ICAHT and provide support for the use of IFN{gamma}-blockade to reduce CRS and neutropenia. Statement of SignificanceDespite clinical success of CAR-T therapy, patients develop toxicities such as cytokine release syndrome and neutropenia, whose co-occurrence impacts their survival and quality-of-life. We recapitulate these toxicities in mice to discover their co-occurrence is driven by Th1-Th17 imbalance following CAR-T administration, which can be prevented via IFN{gamma} blockade.

cancer biology↗