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Biology subjects

Wong, R. A.

Publications and source records attributed to Wong, R. A..

3 recordsLinked to original sources

Therapeutic Targeting of the TGFβ Pathway Augments CAR T cell Efficacy in Glioblastoma

Chimeric Antigen Receptor (CAR) T therapy represents a promising approach to improve outcomes for patients with high-grade gliomas (HGG). Recently, we reported on a phase I trial assessing the local delivery of CAR T cells for HGG. Despite notable clinical benefits to CAR T treatment, clinical responses were highly variable between patients. Here we report that TGF{beta} levels in the tumor cavity fluid (TCF) decreased following CAR T treatment and that lower TGF{beta} levels positively correlated with improved patient responses to CAR T therapy. Patients were stratified based on baseline TGF{beta} levels in the TCF before CAR T therapy. Single-cell RNA sequencing of patient tumor tissues identified significant upregulation of genes associated with angiogenesis and epithelial-to-mesenchymal transition, and IL6 and SLRP pathways in TGF{beta} high patients, while IL2, chemokine signaling and NK-mediated cytotoxicity pathways were significantly upregulated in TGF{beta} low patients. Preclinically, we demonstrated that systemic treatment with a TGF{beta}R1 inhibitor markedly improved CAR T efficacy in syngeneic murine glioma models, correlating with changes in the tumor microenvironment (TME) that benefited both endogenous and CAR T cell phenotype and trafficking. Further studies demonstrated that inhibition of the TGF{beta} pathway in CAR T cells, through either TGF{beta}R1 inhibitor or CRISPR/Cas9 knockout of TGF{beta}R2 (TGF{beta}R2-KO), significantly enhanced CAR T cell expansion and antitumor activity. Collectively, our clinical and preclinical findings strongly indicate that targeting the TGF{beta} pathway could significantly enhance CAR T therapy for patients with high-grade gliomas.

cancer biology↗

Overcoming myeloid-driven resistance to CAR T therapy by targeting SPP1

Chimeric antigen receptor (CAR) T cell therapy faces notable limitations in treatment of solid tumors. The suppressive tumor microenvironment (TME), characterized by complex interactions among immune and stromal cells, is gaining recognition in conferring resistance to CAR T cell therapy. Despite the abundance and diversity of macrophages in the TME, their intricate involvement in modulating responses to CAR T cell therapies remains poorly understood. Here, we conducted single-cell RNA sequencing (scRNA-seq) on tumors from 41 glioma patients undergoing IL13R2-targeted CAR T cell therapy, identifying elevated suppressive SPP1 signatures predominantly in macrophages from patients who were resistant to treatment. Further integrative scRNA-seq analysis of high-grade gliomas as well as an interferon-signaling deficient syngeneic mouse model--both resistant to CAR T therapy--demonstrated the role of congruent suppressive pathways in mediating resistance to CAR T cells and a dominant role for SPP1+ macrophages. SPP1 blockade with an anti-SPP1 antibody abrogates the suppressive TME effects and substantially prolongs survival in IFN signaling-deficient and glioma syngeneic mouse models resistant to CAR T cell therapy. These findings illuminate the role of SPP1+ macrophages in fueling a suppressive TME and driving solid tumor resistance to CAR cell therapies. Targeting SPP1 may serve as a universal strategy to reprogram immune dynamics in solid tumors mitigating resistance to CAR T cell therapies.

cancer biology↗

CAR T cell therapy drives endogenous locoregional T cell dynamics in a responding patient with glioblastoma

CAR T cell therapy has transformed clinical care and management of patients with certain hematological cancers. However, it remains unclear whether the success of CAR T cell therapy relies solely on CAR T cell engagement with tumor antigen, or if it also requires the stimulation of an individual patients endogenous T cell response. Here, we performed combined analysis of longitudinal, single cell RNA and T cell receptor sequencing on glioblastoma tumors, peripheral blood (PB), and cerebrospinal fluid (CSF) from a patient with recurrent multifocal glioblastoma that underwent a remarkable response followed by recurrence on IL13RA2-targeted CAR T cell therapy (Brown et al. 2016). Single cell analysis of a tumor resected prior to CAR T cell therapy revealed the existence of an inflamed tumor microenvironment including a CD8+ cytotoxic, clonally expanded and antigen specific T cell population that disappeared in the recurrent setting. Longitudinal tracking of T cell receptors uncovered distinct T cell dynamics classes in the CSF during CAR T cell therapy. These included T cell clones with transient dynamics, representing intraventricular CAR T cell delivery and endogenous T cell recruitment from the PB into the CSF; and a group of T cells in the cerebrospinal fluid, that tracked with clonally expanded tumor resident T cells and whose dynamics contracted concomitantly with tumor volume. Our results suggest the existence of an endogenous T cell population that was invigorated by intraventricular CAR T cell infusions, and combined with the therapy to produce a complete response.

immunology↗