Quiñones‐Hinojosa, Alfredo

Abstract Glioblastoma (GBM) remains the most lethal primary brain cancer due to its remarkable metabolic plasticity and therapeutic resistance. Here, we identify cholesterol dependency as a therapeutically exploitable vulnerability in GBM using two FDA-approved drugs: the H1 histamine antagonist clemastine and the retinoid X receptor agonist bexarotene. Combined treatment induces potent synergistic anti-tumor activity across patient-derived glioma models, suppressing proliferation, stemness, and survival at sub-IC50 concentrations. Mechanistically, this therapy disrupts cholesterol biosynthesis, transport, and homeostasis, triggering endoplasmic reticulum stress and activation of the unfolded protein response, ultimately leading to autophagy and apoptotic cell death. Orthotopic patient-derived glioma models recapitulate these mechanisms in vivo, where local intracranial administration significantly reduces tumor progression and prolongs survival using fourfold lower doses than systemic intraperitoneal delivery. Single-cell RNA sequencing revealed activation of regeneration and plasticity programs, accompanied by immune microenvironment remodeling and enhanced inflammatory signaling. Importantly, syngeneic models preserved immune cell composition, supporting future integration with immunotherapeutic strategies. Together, these findings establish cholesterol dysregulation–induced metabolic collapse as a promising therapeutic approach for GBM.

Background Lumbar facet arthropathy (LFA) is a degenerative, arthritic joint disorder and a common specific cause of axial low back pain and functional impairment. Currently, no disease-modifying therapies are available for symptomatic LFA. Mesenchymal stem/stromal cell (MSC)-based therapy represents an emerging regenerative treatment modality with the promise to target the underlying pathophysiology of LFA. Despite encouraging clinical evidence supporting the safety and efficacy of MSC therapy in other osteoarthritis, its therapeutic utility in LFA remains largely unexplored. We recently completed a prospective, single-arm, open-label phase I clinical trial that demonstrated a favourable safety profile and preliminary clinical benefit following intra-articular administration of bone marrow-derived MSCs (BMSCs) in patients with symptomatic LFA. Building on these findings, we present the protocol for CellKine II , a prospective, randomised, double-blind, placebo-controlled, cross-over phase II clinical trial to evaluate the safety and preliminary efficacy of intra-articular delivery of allogeneic, culture-expanded BMSCs in patients with painful LFA. Methods and analysis This study is a single-centre, randomised, double-blind, placebo-controlled, cross-over phase II trial with a target accrual of 40 patients. Eligible patients will be randomly assigned in a 1:1 ratio to receive a single intra-articular injection of either Arm A: BMSC or Arm B: Placebo (dimethyl sulfoxide). At the 6-month follow-up, all patients will be unblinded. Patients initially randomised to Arm A will continue follow-up for up to 12 months. Patients initially randomised to Arm B may cross over to receive the BMSC treatment, followed by an additional 12 months of post-BMSC treatment follow-up, or they may continue observation for another 6 months without BMSC treatment. Overall, each patient will be followed up to 12 months after BMSC treatment. The primary endpoints are back pain, functional outcomes and adverse events at 6 months post-randomisation. Ethics and dissemination This study will be conducted in compliance with U.S. federal regulations and Mayo Clinic institutional research policies and procedures. The protocol has been approved by the Mayo Clinic Institutional Review Board (IRB) and the Data Safety Monitoring Board (IRB No. 21-013278). The results of this trial will be disseminated through publication in peer-reviewed journals and on ClinicalTrials.gov. Trial registration number NCT06001853 .

Abstract Glioblastoma (GBM) is among the most aggressive and lethal primary brain cancers. A major therapeutic challenge is that the standard chemotherapeutic agent temozolomide (TMZ) is associated with drug resistance and lacks tumor-specificity. The development of targeted drug delivery systems encapsulating new chemotherapeutic agents may overcome these limitations. Fucoidan has been reported to exhibit tumor-targeting properties through its high binding affinity for P-selectin overexpressed on both GBM cells and activated brain microvascular endothelial cells (BMECs) within and surrounding tumors. Verteporfin (VP), a benzoporphyrin derivative, has been reported to suppress Yes-associated protein (YAP) activity, inhibit tumor angiogenesis, and exhibit antitumor activity in heterogeneous GBM. However, the hydrophobic nature of VP limits its bioavailability, reducing therapeutic efficacy and necessitating high doses that may increase the risk of adverse effects. To address this challenge, we synthesized VP-laden, fucoidan-coated nanoparticles (VP@NP-F), and VP-laden nanoparticles without fucoidan coating (VP@NP). Their capability of enhancing VP delivery and antitumor efficacy was evaluated using human BMECs and patient-derived primary GBM cells (GBM1a). VP@NP-F exhibits ∼4-fold and ∼1.8-fold greater uptake in BMECs and GBM1a than VP@NP, demonstrating the fucoidan coating enhances targeting and internalization. The half-maximal inhibitory concentration (IC50) value of VP@NP-F is ∼12.3-fold and ∼3-fold lower than that of free VP and VP@NP, respectively. These data suggest the therapeutic advantage of the VP-laden, fucoidan-coated nanoparticles in vitro, which warrants further in vivo investigation in the future.

ABSTRACT Glioblastoma (GBM) is universally lethal despite decades of research to find effective treatments. This highlights the need to identify druggable targets essential for sustaining the malignant phenotype but dispensable for normal tissue. We propose that the enzyme α-tubulin acetyl transferase ( ATAT1 ) meets these criteria. ATAT1 acetylates α-tubulin at lysine 40, which increases microtubule stability and promotes microtubule-based transport. While ATAT1 knockout mice have only a very mild phenotype, ATAT1 suppression in GBM has multiple therapeutic effects by reducing tumor invasion, proliferation, and therapeutic resistance. These translate not only into improved survival with ATAT1 targeting by itself, but also into synergy when ATAT1 deletion is combined with FDA approved therapies. This study strongly supports our conclusion that ATAT1 is a promising therapeutic target in GBM.

Abstract Background Glioblastoma (GBM) remains a devastating cancer with limited treatment options, largely due to its heterogeneity. While supramaximal resection has recently provided survival benefits, therapeutic profiling of different tumor compartments, particularly its infiltrative edge remains largely unexplored. Methods Here, we leveraged magnetic resonance imaging (MRI)-guided multi-sampling, collecting 2 cores and 2 margins per case, to query GBM heterogeneity. Whole-exome and RNA-seq with drug testing in two patient-derived 3D models were used to reveal similarities and differences in genomic and transcriptomic makeups, cellular compositions, and drug responses across cores and margins. Bioinformatics interrogations further identified response biomarkers. Results Mutation analysis showed that oncogenes exhibited a higher degree of spatial heterogeneity than tumor suppressor genes, regardless of MRI status. While the mesenchymal transcriptional subtype with extracellular matrix remodeling, stress response, and immune programs were preferentially enriched in enhancing cores, proneural tumors with neurological processes favored non-enhancing margins. Using a 15-drug GBM-targeted panel, ERK (ulixertinib) and PI3K pathway (paxalisib, CC-115) inhibitors showed preferential efficacy in enhancing cores and non-enhancing margins, respectively. The anti-apoptosis, pan-Bcl2 agent navitoclax and the epigenetic drug trotabresib represented the most effective, tumor-wide monotherapies. Importantly, drug combinations generally outperformed single agents across all regions. Conclusions This work demonstrates the regional heterogeneity of therapeutic vulnerabilities in GBM ex vivo, showing various drugs with tumor-wide or MRI-enhancement informed activity. These findings offer preclinical bases of numerous monotherapies and drug combinations for future clinical trial design.

Abstract Background The current treatment of glioblastoma involves resection followed by radiotherapy (RT) and temozolomide. Rapid early progression (REP) of tumor in the surgery-to-radiotherapy interval (SRI) has been described using categorical or semi-quantitative assessments and is associated with inferior clinical outcomes. This study seeks to establish and validate a quantitative definition for REP and examine how REP could inform future therapy. Methods Volumes of tumor and resection cavity at 3 time points—preoperative, postoperative and RT-planning (pre-RT)—were contoured among patients who had undergone standard of care. A minimal, but clinically appreciable, threshold for defining REP based on change in tumor volume was established, validated, and subsequently used to assess actionable predictors of REP and its prognostic value. Results An increase of >2 cc in volume or a new satellite tumor between the post-operative to planning MRI was found to be a sensitive, pragmatic, and statistically significant cutoff for REP (P = .002). Actionable predictors such as SRI of 6 weeks and a > 5 cc residual immediate post-operative tumor volume were found to be statistically significant predictors of REP. REP was also found to be a statistically significant prognostic indicator for overall survival (P = .002) and progression-free survival. Conclusion These findings support that an increase in tumor volume between post-operative and pre-RT MRI of >2 cc is the ideal working definition of REP in this clinical setting. Furthermore, REP could serve as a prognostic ­biomarker to track treatment response. Additionally, 2 actionable predictors of REP, post-op residual tumor volume and SRI, are identified.