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Biology subjects

Reville, P. K.

Publications and source records attributed to Reville, P. K..

6 recordsLinked to original sources

Single-Cell Atlas of Renal Cell Carcinoma Brain Metastasis Uncovers Mechanisms of Immune Dysfunction and Resistance

Brain metastasis (BM) in renal cell carcinoma (RCC) remains poorly understood and often resistant to immune checkpoint inhibitors. We generated a large single-nucleus RNA-seq data of RCC BM, profiling 14 BM samples alongside matched extracranial metastases and primary tumors. Tumor cells in BM displayed neuronal infiltration, neural-like adaptation, and marked remodeling of the microenvironment, including expansion of immunosuppressive myeloid cells and depletion of antigen-presenting dendritic cells. Tumor, immune, and stromal cells exhibited metabolic rewiring characterized by fatty-acid metabolism, oxidative phosphorylation, and MYC-driven programs. CD8 T cells showed terminal exhaustion and impaired proliferative capacity, and tertiary lymphoid structures were absent. Spatial profiling of 12 BM samples (13,128 cells) validated key cellular interactions, while ligand-receptor analysis revealed immunoregulatory circuits between tumor, stromal, and immune cells. These findings define BM-specific adaptations that promote immune evasion and resistance, revealing therapeutic vulnerabilities in RCC BM. SIGNIFICANCESingle-nucleus RNA-sequencing profiling reveals tumor, immune, and metabolic adaptations in renal cell carcinoma (RCC) brain metastases, including neuroglial remodelling and immunosuppressive niche formation. These findings identify immune evasion mechanisms that could contribute to therapeutic resistance, providing new avenues for site-specific therapeutic interventions to improve treatment efficacy and outcomes in patients with RCC BM.

cancer biology↗

Spatial Transcriptomics Reveals Inflammation and Trans-differentiation States of Acute Myeloid Leukemia in Extramedullary and Medullary Tissues

Acute myeloid leukemia (AML) is a heterogeneous disease of the bone marrow (medullary) but can also involve extramedullary tissues. While single cell dynamics of AML in suspension are previously explored, a comprehensive spatial transcriptomic assessment in AML remain underexplored. Here, we used Visium spatial transcriptomics to resolve medullary and extramedullary AML environments. We reveal spatial co-localization of monocytes and granulocyte-monocyte progenitors with leukemic populations in the bone marrow, sharing molecular signatures with extramedullary sites. Cell-cell communication via the CXCL12- CXCR4 axis correlated with PI3K/AKT/mTOR signaling in high inflammatory niches. Trans- differentiation states were concentrated in AML-infiltrated regions, with committed-like AML populations present in inflammatory niches and away from the trabeculae, while primitive-like AML cells localized near the endosteal niche. We validated these findings in GeoMx-based Digital Spatial profiling (DSP). Our study applied multimodal spatial transcriptomic approaches to characterize the spatial hierarchy and microenvironmental dynamics of AML differentiation states. We also demonstrated the feasibility of applying Visium-based spatial transcriptomics in decalcified bone tissues.

cancer biology↗

Multimodal Spatial Proteomic Profiling in Acute Myeloid Leukemia

Acute myeloid leukemia (AML) resides in an immune rich microenvironment, yet, immune-based therapies have faltered in eliciting durable responses. Bridging this paradox requires a comprehensive understanding of leukemic interactions within the bone marrow microenvironment. We optimized a high-throughput tissue-microarray based pipeline for high-plex spatial immunofluorescence and mass cytometry imaging on a single slide, capturing immune, tumor, and structural components. Using unbiased clustering on the spatial K function, we unveiled the presence of tertiary lymphoid-like aggregates in bone marrow which we validated using spatial transcriptomics and an independent proteomics approach. We then found validated TLS signatures predictive of outcomes in AML using an integrated public 480 patient transcriptomic dataset. By harnessing high-plex spatial proteomics, we open the possibility of discovering of novel structures and interactions that underpin leukemic immune response. Further, our studys methodologies and resources can be adapted for other bone marrow diseases where decalcification and autofluorescence present challenges.

cancer biology↗

BRG1/BRM inhibitor targets AML stem cells and exerts superior preclinical efficacy combined with BET or Menin inhibitor

BRG1 (SMARCA4) and BRM (SMARCA2) are the core ATPases of chromatin remodeling BAF (BRG1/BRM-associated factor) complexes, which enable transcription factors/co-factors to modulate gene-expressions, mediating growth, differentiation-arrest and survival of AML cells. In AML with MLL1r (MLL1 rearrangement) or mutant (mt) NPM1, although monotherapy with Menin inhibitor (MI) induces clinical remissions, most patients either fail to respond or relapse. FHD-286 is a selective BRG1/BRM inhibitor, undergoing clinical development in AML. Here, FHD-286 induced differentiation and lethality in AML cells with MLL1r or mtNPM1, reducing chromatin accessibility and repressing c-Myc, PU.1 and CDK4/6. Whereas FHD-286 monotherapy reduced AML burden, leukemia-initiating potential and improved survival, FHD-286 combinations with MI, BET inhibitor, decitabine or venetoclax was significantly more effective in reducing AML burden and improved survival, without significant toxicity, in xenograft models of AML with MLL1r or mtNPM1. These findings highlight promising FHD-286-based combinations for therapy of AML with MLL1r or mtNPM1. Statement of SignificanceInhibition of BRG1/BRM ATPases by FHD-286 reduced chromatin accessibility, repressed c-Myc, PU.1 and CDK4/6, inducing differentiation, leukemia-initiating potential and lethality in AML stem-progenitor cells. FHD-286-based combinations with Menin or BET inhibitor or decitabine reduced AML burden and improved survival in xenograft models of AML with MLL rearrangement or mutant NPM1.

cancer biology↗

CD8 T-cell dysfunction is linked with CAR T-cell failure and can be mitigated by a non-alpha IL-2 agonist, pegenzileukin

Chimeric antigen receptor (CAR) T-cell therapy has been a breakthrough for relapsed or refractory large B-cell lymphoma (rrLBCL). However, suboptimal CAR T-cell activity can lead to therapeutic failure and dismal outcome. Using single cell RNA-sequencing of rrLBCL tumors, we identify a prominent population of clonally expanded dysfunctional CAR+ CD8 T-cells indicative of ongoing tumor cell engagement, proliferation, and dysfunction at the time of progression from CAR T-cell therapy. Furthermore, we show that rrLBCL patient-derived CAR T-cells are more prone to dysfunction and loss of cytotoxicity compared to healthy donor-derived CAR T-cells. Using both antigen-driven and CAR-driven models of T-cell dysfunction, we show that pegenzileukin, a non-alpha IL2 agonist, can prevent T-cell dysfunction. In both in vitro and in vivo CAR T-cell models, pegenzileukin improved T-cell expansion and tumor control. This provides pre-clinical rational for use of pegenzileukin in combatting T-cell dysfunction, a central mechanism of CAR T-cell failure. HIGHLIGHTSO_LITumor-infiltrating CD8 CAR T-cells show clonal expansion and dysfunction at the time of progression. C_LIO_LIrrLBCL patient-derived CAR T-cells are more prone to dysfunction compared to healthy-donor-derived CAR T-cells. C_LIO_LIPegenzileukin, a non-alpha IL2 agonist, rescues antigen- and CAR-driven CD8 T-cell dysfunction and improves CAR T-cell responses in vivo. C_LI

immunology↗

Single-cell Characterization of Acute Myeloid Leukemia and its Microenvironment Following PD-1 Blockade Based Therapy

Acute myeloid leukemia (AML) and effector cells of immune checkpoint blockade (ICB) therapy co-reside in a complex bone marrow (BM) milieu. The interplay of tumor intrinsic and microenvironment (TME) mechanisms that influences the response to ICB-based therapies in AML have not been elucidated. Here we report our analyses of single cell RNA profiling of more than 127,000 BM cells from healthy donors and relapsed/refractory (R/R) AML patients at pre/post treatment with azacitidine/nivolumab, paired with single cell T cell receptor (TCR) repertoire profiles, to uncover factors impacting response and resistance. Loss of chromosome 7/7q conferred an immunosuppressive TME and was associated with resistance to ICB-based therapy in R/R AML. Our trajectory analysis revealed a continuum of CD8+ T cell phenotypes, characterized by differential expression of granzyme B (GZMB) and GZMK. GZMK expression defined a BM residing memory CD8+ T cell subset with stem-like properties likely an intermediary between naive and cytotoxic lymphocytes. Responses to ICB-based therapy were primarily driven by novel and expanded T cell clonotypes. Our findings support an adaptable T cell plasticity in response to PD-1 blockade in AML. Disentangling AML cells from their complex, immune-rich microenvironment revealed characteristics that shaped resistance to ICB-based therapy and could inform strategies to target AML vulnerabilities. SignificanceDetermining the cellular and molecular underpinnings of response and resistance to PD-1 blockade based therapy in AML can guide immune-based therapeutic strategies. Our results reveal AML intrinsic characteristics (chromosome 7/7q status and oxidative stressors) and tumor microenvironment to modulate responses to checkpoint blockers. CD8 cells exist in the bone marrow in a continuum with GZMK expression defining a memory, stem-like T cell population that could play a role in response to therapy.

cancer biology↗