Publications by authors named "Victor A Arrieta"

Purpose: The blood-brain barrier (BBB) impedes the passage of most circulating drugs into the brain. Low-intensity pulsed ultrasound with microbubbles (LIPU/MB) transiently opens the BBB, improving parenchymal drug penetration. Parenchymal drug retention following short-lived BBB opening is unknown.

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Background: Immunotherapy has revolutionized cancer treatment but has yet to be translated into brain tumors. Studies in other solid tumors suggest a central role of B-cell immunity in driving immune checkpoint blockade efficacy. In glioblastoma (GBM), tumor B-cells are driven into a regulatory B-cell state that suppresses immune activation and T-cell function.

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Although GBM's immunosuppressive environment is well known, the tumor's resistance to CD8+ T cell killing is not fully understood. Our previous study identified Checkpoint Kinase 2 (Chek2) as the key driver of CD8+ T cell resistance in mouse glioma through an in vivo CRISPR screen and demonstrated that Chk2 inhibition, combined with PD-1/PD-L1 blockade, significantly enhanced CD8+ T cell-mediated tumor killing and improved survival in preclinical model. Here, we aimed to elucidate the immunosuppressive function of Chek2.

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Background: The blood-brain barrier (BBB) impedes the passage of most circulating drugs into the brain. Low-intensity pulsed ultrasound with microbubbles (LIPU/MB) transiently opens the BBB, improving parenchymal drug penetration. Parenchymal drug permanence upon short-lived BBB opening is unknown.

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Cerebral endothelial cell (EC) injury and blood-brain barrier (BBB) permeability contribute to neuronal injury in acute neurological disease states. Preclinical experiments have used animal models to study this phenomenon, yet the response of human cerebral ECs to BBB disruption remains unclear. In our phase I clinical trial (ClinicalTrials.

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Background: Glioblastoma (GB) remains a formidable challenge in neuro-oncology, with immune checkpoint blockade (ICB) showing limited efficacy in unselected patients. We previously recently established that MAPK/ERK signaling is associated with overall survival following anti-PD-1 and anti-CTLA-4 treatment in recurrent GB. However, the causal relationship between MAPK/ERK signaling and susceptibility to ICB, as well as the mechanisms underlying this association, remain poorly understood.

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Article Synopsis
  • Glioblastoma is a challenging brain cancer that often resists standard immunotherapy, but Botensilimab, a specialized antibody, has shown potential in treating this type of cancer.
  • In preclinical studies, a mouse version of Botensilimab demonstrated effectiveness when used alone or with doxorubicin combined with ultrasound techniques, leading to significant immune responses in treatment-resistant glioblastoma.
  • Results indicated that this combination therapy not only effectively targeted and reduced tumor-associated immune cells but also fostered a strong infiltration of harmful T cells, achieving a remarkable cure rate in mice and suggesting promising implications for human treatments.
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Objective: Neurosurgery is one of the most competitive specialties, and navigating the match process is often challenging for aspiring applicants. Here, we analyze insights from the National Resident Matching Program Director Surveys, illustrating evolving trends in applicant selection for interviews and for the ranking process, and providing a comparison with other specialties.

Methods: We evaluated 7 surveys administered from 2012 to 2022.

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Article Synopsis
  • Most drugs struggle to effectively treat glioblastoma (GBM) due to limited penetration across the blood-brain barrier, which makes their efficacy low.
  • This study utilizes low-intensity pulsed ultrasound (LIPU) combined with microbubbles (MB) to temporarily open the blood-brain barrier, significantly increasing the delivery of liposomal doxorubicin and PD-1 blocking antibodies (aPD-1) in both human and animal models.
  • Results show that this method improves drug concentrations, enhances immune responses in cells, and contributes to long-term survival in GBM mouse models, highlighting its potential for improving GBM treatments.
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Immunoglobulin G4-related disease (IgG4-RD) is a rare autoimmune disorder with an unknown etiology. Using orthogonal immune profiling and automated sequential multiplexing, we found an enhanced frequency of activated circulating B cells, antigen-presenting myeloid cells in peripheral blood, and a distinct distribution of immune cells within the CNS lesions. Prohibitin-expressing CD138+ plasma B cells and CD11c+ dendritic cells have been found interacting with T cells resulting in irmnune cell activation within the lesion.

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Purpose: Only a small percentage of Hispanic patients have been included in studies that developed prognostic models for breast cancer and brain metastases. Therefore, there is a clear need for tools tailored to this demographic. This study assesses the efficacy of common prognostic tools in a Hispanic population.

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We recently discovered a putative paclitaxel response predictive biomarker for glioblastoma and breast cancer using the whole genome CRISPR knockout screen. The biomarker candidate was validated in two independent breast cancer patient cohorts that received taxane treatment. To further evaluate the potential application of this biomarker in the clinic for patients with glioblastoma, a prospective validation in cohorts of patients with glioblastoma is essential and will be performed as part of our ongoing phase II clinical trial (NCT04528680).

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Introduction: Glioblastoma multiforme (GBM) pathobiology is characterized by its significant induction of immunosuppression within the tumor microenvironment, predominantly mediated by immunosuppressive tumor-associated myeloid cells (TAMCs). Myeloid cells play a pivotal role in shaping the GBM microenvironment and influencing immune responses, with direct interactions with effector immune cells critically impacting these processes.

Methods: Our study investigates the role of the CXCR6/CXCL16 axis in T-cell myeloid interactions within GBM tissues.

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Article Synopsis
  • The study explored the combination of paclitaxel and carboplatin for treating recurrent glioblastoma, showing that low-intensity pulsed ultrasound and microbubbles can enhance drug delivery to the brain.
  • In preclinical models, the combination was found to be effective, resulting in a higher susceptibility of glioma cell lines and demonstrating synergy in 55% of cases.
  • The findings suggest that the combination therapy could lead to better outcomes than individual treatments, and this approach is being further investigated in a phase II clinical trial.
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Article Synopsis
  • Understanding the spatial arrangement and interactions of immune cells in glioblastoma (GBM) is vital for creating therapies that counteract the tumor's immunosuppressive environment.
  • Our research indicates that B and T cells establish close clusters in GBM, but B cells can inhibit CD8 T cell activation.
  • We discovered that by stimulating B cells, they can enhance T cell activation and lead to improved proliferation compared to both naive B cells and dendritic cells, making them promising candidates for cellular vaccine strategies.
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Glioblastoma (GBM) is a malignancy dominated by the infiltration of tumor-associated myeloid cells (TAMCs). Examination of TAMC metabolic phenotypes in mouse models and patients with GBM identified the de novo creatine metabolic pathway as a hallmark of TAMCs. Multi-omics analyses revealed that TAMCs surround the hypoxic peri-necrotic regions of GBM and express the creatine metabolic enzyme glycine amidinotransferase (GATM).

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Purpose: Evidence suggests that MAPK pathway activation, as measured by ERK1/2 phosphorylation (p-ERK), predicts overall survival (OS) in patients with recurrent glioblastoma receiving anti-PD-1 therapy. We aimed to validate these findings in independent cohorts.

Experimental Design: In a 24-patient clinical trial on recurrent glioblastoma and high-grade gliomas, we examined the link between p-ERK levels and OS.

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A paucity of chemotherapeutic options for metastatic brain cancer limits patient survival and portends poor clinical outcomes. Using a CNS small-molecule inhibitor library of 320 agents known to be blood-brain barrier permeable and approved by the FDA, we interrogated breast cancer brain metastasis vulnerabilities to identify an effective agent. Metixene, an antiparkinsonian drug, was identified as a top therapeutic agent that was capable of decreasing cellular viability and inducing cell death across different metastatic breast cancer subtypes.

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Background: Low-intensity pulsed ultrasound with concomitant administration of intravenous microbubbles (LIPU-MB) can be used to open the blood-brain barrier. We aimed to assess the safety and pharmacokinetics of LIPU-MB to enhance the delivery of albumin-bound paclitaxel to the peritumoural brain of patients with recurrent glioblastoma.

Methods: We conducted a dose-escalation phase 1 clinical trial in adults (aged ≥18 years) with recurrent glioblastoma, a tumour diameter of 70 mm or smaller, and a Karnofsky performance status of at least 70.

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Article Synopsis
  • The study investigates how intrinsic tumor-cell mechanisms, specifically kinases, allow glioblastoma (GBM) cells to evade detection by CD8 T cells, highlighting checkpoint kinase 2 (Chek2) as a key player.
  • An in vivo CRISPR screen identified Chek2 as crucial for tumor cell escape, and its inhibition, along with PD-1 or PD-L1 blockade, improves survival in preclinical glioma models.
  • The research shows that reducing Chek2 enhances antigen presentation and T-cell activation while analysis of human GBMs shows an inverse relationship between Chek2 expression and immune responsiveness, suggesting it as a potential target for improving immune checkpoint therapies in GBM.
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Introduction: The immunosuppressive tumor microenvironment (TME) is a major barrier to the efficacy of chimeric antigen receptor T cells (CAR-T cells) in glioblastoma (GBM). Transgenic expression of IL15 is one attractive strategy to modulate the TME. However, at present, it is unclear if IL15 could be used to directly target myeloid-derived suppressor cells (MDSCs), a major cellular component of the GBM TME.

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Immune checkpoint blockade (ICB) has revolutionized modern cancer therapy, arousing great interest in the neuro-oncology community. While several reports show that subsets of patients with glioma exhibit durable responses to immunotherapy, the efficacy of this treatment has not been observed for unselected patient populations, preventing its broad clinical implementation for gliomas and glioblastoma (GBM). To exploit the maximum therapeutic potential of ICB for patients with glioma, understanding the different aspects of glioma-related tumor immune responses is of critical importance.

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The glioma tumor microenvironment (TME) is complex and heterogeneous, and multiple emerging and current technologies are being utilized for an improved comprehension and understanding of these tumors. Single cell analysis techniques such as single cell genomic and transcriptomic sequencing analysis are on the rise and play an important role in elucidating the glioma TME. These large datasets will prove useful for patient tumor characterization, including immune configuration that will ultimately influence therapeutic choices and especially immune therapies.

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Purpose: Paclitaxel (PTX) is one of the most potent and commonly used chemotherapies for breast and pancreatic cancer. Several ongoing clinical trials are investigating means of enhancing delivery of PTX across the blood-brain barrier for glioblastomas. Despite the widespread use of PTX for breast cancer, and the initiative to repurpose this drug for gliomas, there are no predictive biomarkers to inform which patients will likely benefit from this therapy.

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