Citations

Abstract NF2-related schwannomatosis is a genetic condition characterized by mutation in the NF2 gene resulting in tumor formation throughout the nervous system. The most common tumors in these patients include bilateral vestibular schwannomas and multiple meningiomas which, despite their benign classification, lead to significant neurologic deficits including hearing loss, ataxia, hydrocephalus, and brainstem compression. Loss of NF2, which encodes the protein Merlin, is also the most common mutation in spontaneous meningiomas and schwannomas. Current treatment consists of resection followed by radiation for more aggressive tumors. Unfortunately, these treatments are not curative and are associated with significant risk due to tumor location, involvement of neurovasculature, cognitive impairment, and radiation-induced tumor induction. Therefore, identifying additional therapeutics for these patients is critical. Molecular profiling across large cohorts of sporadic meningiomas have identified molecular signatures associated with NF2 mutation, indicating upregulation of Wnt5a/b and the alternative Wnt5a/b-YAP/TAZ signaling pathway. In NF2 knock-out human arachnoid and Schwann cells, we find a significant upregulation of YAP in NF2-null lines compared to controls. Additionally, when stimulated with Wnt5a/b, controls upregulate both beta catenin (canonical Wnt) and YAP (alternative Wnt). However, in NF2-null lines only YAP is increased, indicating a preference for the alternative pathway in the absence of canonical Wnt signaling. In primary NF2-mutant meningioma lines, targeting this pathway via blocking Wnt secretion with the inhibitor LGK974 or YAP signaling with verteporfin, which is FDA approved, results in decreased cell viability and proliferation in vitro. These results indicate activation of the Wnt5a/b-YAP/TAZ alternative signaling pathway in NF2-mutant meningeal and Schwann cells, and a potential therapeutic effect of blocking this pathway in NF2-mutant meningiomas with a previously-FDA approved inhibitor. Additional research is needed on the receptors and molecular mediators playing a role in this pathway and how these drugs may have therapeutic benefits in vivo

Abstract Background and Aims Patients with catecholaminergic polymorphic ventricular tachycardia (CPVT) are at risk for potentially life-threatening arrhythmic events (AEs) even while treated with β-blockers. The aim was to develop a model for individualized prediction of AEs in patients with RYR2-mediated CPVT on β-blocker monotherapy. Methods The derivation and independent validation cohorts included 743 and 129 patients, respectively. AEs were defined as arrhythmic syncope, appropriate implantable cardioverter–defibrillator shock, sudden cardiac arrest (SCA), and sudden cardiac death. Near-fatal or fatal AEs (nf/fAEs) included all AEs except for arrhythmic syncope. Prediction models using Cox regression were developed and internally and externally validated. Results A total of 102 (13.7%) patients in the derivation cohort and 24 (18.6%) patients in the validation cohort experienced ≥1 AE over a median follow-up of 5.1 [interquartile range (IQR), 7.7] and 2.4 (IQR, 4.4) years, respectively. Predictors of AE were arrhythmic syncope or SCA prior to diagnosis and age at β-blocker initiation. In the derivation and validation cohorts, the optimism-corrected C-indices of the models for AE were 0.67 [95% confidence interval (CI) 0.62–0.72] and 0.59 (95% CI 0.48–0.71), respectively. For nf/fAEs, ventricular arrhythmia severity before β-blocker initiation was a fourth independent predictor, and C-indices of the models in the derivation and validation cohorts were 0.74 (95% CI 0.68–0.80) and 0.60 (95% CI 0.47–0.72), respectively. In the derivation cohort, calibration slopes were 1.00 (95% CI 0.59–1.41) for AE and 1.00 (95% CI 0.69–1.32) for nf/fAE. Conclusions These externally validated risk prediction models using clinical parameters accurately distinguished CPVT patients on β-blocker monotherapy at low and high risk for future AEs while treated with β-blockers. These models provide guidance for implementation of clinical management therapies to prevent AEs in patients with CPVT.

IDH1/2 mutations (IDH mut ) increase methylation of DNA and histones in gliomas. IDH mut inhibitors are effective against low-grade IDH mut gliomas, but new strategies against high-grade IDH mut gliomas are needed. Although histone deacetylase inhibitors (HDACi) are ineffective against IDH wt glioblastoma (GBM), their potential in IDH mut gliomas has not been extensively studied. We previously established that IDH mut gliomas are more sensitive to HDACi than IDH wt GBM. Here we show that IDH mut is associated with greater sensitivity to HDACi only in glioma, not in IDH mut chondrosarcoma or cholangiocarcinoma. While HDACi induced more histone acetylation and gene regulation in IDH mut glioma than in IDH wt GBM, such acetylation was mostly within gene deserts, whereas IDH mut glioma promoters paradoxically lost histone acetylation. Two mediators of HDACi resistance, YAP and TAZ, were methylated and suppressed in IDH mut gliomas but not in other IDH mut cancers. Inducing YAP or TAZ expression in IDH mut gliomas conferred resistance to HDACi. Finally, belinostat extended in vivo survival only in IDH mut glioma models, not in IDH mut GBM models. Our findings provide a mechanistic rationale for further studies of HDACi in patients with IDH mut glioma, as well as the potential use of YAP/TAZ as a biomarker of HDACi sensitivity in cancers.

Abstract Background: Black or African Americans (AA) with Parkinson’s disease (PD) are underrepresented in both care and research and experience significant health disparities. The existing literature provides limited guidance on how to enhance the engagement of AA individuals in PD care and research, particularly from the perspectives of AA patients, care partners, and healthcare providers. This project aimed to (1) describe the use of Community Engagement (CE) Studios as a community-engaged research approach to inform culturally appropriate and inclusive research and (2) examine factors influencing AA engagement in PD-related activities. Methods: We conducted three CE Studios: one with AA with PD and care partners (N = 6), one with healthcare providers of AA with PD (N = 8), and one with AA with PD, care partners, and healthcare providers (N = 4). Results: The CE Studios informed the design (e.g., cultural appropriateness) and conduct (e.g., accessibility) of the planned PD project, as well as identifying stakeholders to engage with, improving alignment between research and the AA community. We highlighted the importance of multifaceted factors, including environmental (e.g., segregation), biological (e.g., symptoms), sociocultural (e.g., not being invited), and behavioral (e.g., empowerment) domains, which influence AA engagement. Conclusions: The CE Studios method is a feasible and useful approach for understanding the perspectives of AA in PD. It is possible to conduct an in-depth exploration of community perspectives by synthesizing comprehensive analyses and leveraging additional frameworks. These efforts include identifying barriers to engagement, recognizing locally relevant individuals, and refining PD-related care to enhance cultural appropriateness.

Abstract Background: The transcriptional cofactor Yes-associated protein (YAP) is activated in CCA pathophysiology. While canonical regulation by the Hippo pathway resulting in phosphorylation at serine 127 (S127) is inhibitory, SRC-family kinases (SFKs) phosphorylate YAP at tyrosine 357 (Y357), causing activation. Previously, cholangiocytes, hepatic progenitor cells (HPCs), and even mature hepatocytes were suggested as potential cells of origin of CCA, which highlights the plasticity in the liver. However, the role of YAP activation in selecting the cell of origin and lineage commitment during hepatobiliary oncogenesis is unknown. Aim: To determine if YAP Y357 phosphorylation is required for CCA tumorigenesis, we utilized an in vivo model. Unexpectedly, a shift in tumor phenotype to hepatocellular carcinoma (HCC) was identified. Subsequently, we further explored cell signaling and cell of origin contributions to this phenotypic switch. Method: C57BL/6 mice underwent biliary transfection with Sleeping Beauty transposase and transposons encoding myr-AKT and either YAP S127A (YAP-S) or YAP S127A/Y357F (YAP-SY), followed by IL-33 treatment. Tumor nodule count, histologic classification, and liver-to-body ratio were assessed at necropsy after 10 weeks. RNA sequencing and ingenuity pathway analysis (IPA) were performed on HCC and CCA nodules. To determine the cell of origin, tumors were generated in lineage tracing mice (Rosa26 mT/mG mice treated with AAV8-TBG-Cre). Finally, two tumor-derived cell lines with YAP-SY and constitutive AKT expression were isolated. Results: Both YAP-S and YAP-SY models developed similar tumor numbers and bulk. YAP-S mice generated frequent CCA (25.3%) in addition to combined HCC-CCA (cHCC-CCA) tumors (10.7%) and HCC (64%), whereas YAP-SY mice developed predominantly HCC (86.7%), with rare CCA (8.8%) and mixed tumors (4.5%). Transcriptome analysis identified 3,367 differentially expressed genes (DEGs) between HCC from YAP-SY mice and CCA from YAP-S mice. Notably, YAP-regulated genes had decreased expression in the HCC from YAP-SY mice. IPA revealed key upstream regulators, including cytokines and growth factors (e.g., TGFB1, TNF, INFG, CSF2, IL6, IL1B, IL4) and transcription factors (e.g., TP53, JUN, SP1, NFKBIA, STAT3). Lineage tracing demonstrated HCC originated from hepatocytes and CCA from cholangiocytes in both models. Finally, gene expression analysis of novel syngeneic cancer cell lines from YAP-SY mice showed mixed features of both HCC and CCA. Conclusion: In this murine model, we found that sub-maximal YAP activation is associated with increased formation of HCC from hepatocytes, while a higher level of YAP activation due to YAP Y357 phosphorylation is associated with efficient formation of CCA. We identified cytokines and growth factors that may orchestrate this phenotypic switch. Finally, we developed novel syngeneic cancer cell lines with cHCC-CCA characteristics. Citation Format: Muhammed D. Aksu,Jayla T. Millender,Ryan D. Watkins,Jennifer A. Yonkus,EeeLN H. Buckarma,Nathan W. Werneburg,Daniel R. O'Brien,Chantal E. McCabe,Rondell P. Graham,Gregory J. Gores,Rory L. Smoot,Caitlin B. Conboy. YAP tyrosine phosphorylation regulates lineage commitment in liver tumorigenesis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 1457.

ABSTRACTBackgroundPsychological safety is critical to early and continued engagement with healthcare providers, yet no studies have explored this concept in relationship to cancer care. Black/African American (“Black”) individuals experience disparities in breast and ovarian cancer beyond what can be explained biologically.AimsWe explored factors influencing psychological safety among Black breast and ovarian cancer patients and their family members.MethodsSocioeconomically diverse patients with a personal diagnosis or family history of breast and/or ovarian cancer were invited to complete a semi‐structured qualitative interview on their cancer and healthcare experiences between September 2020 and April 2021. Informed by principles of grounded theory, interview transcripts were qualitatively analyzed for thematic content related to psychological safety.ResultsBlack breast and ovarian cancer patients and their family members described personal and community experiences and structural components of the healthcare system that suggested they may receive differential cancer care due to their race, placing them on guard. This posture was mediated by several self‐identified factors that added to or detracted from their comfort, including provider racial and gender concordance in healthcare, personalized care, and effective communication. The priorities and perceptions of care in participants receiving care in safety net clinics were more focused on what was feasible given resource limitations rather than what was ideally desired.ConclusionsImplementation of strategies to promote psychological safety with Black cancer patients may foster improved patient experiences, as well as encourage early screening, patient engagement, and treatment continuation.

Abstract Background Morbidity from bacteremia may be exacerbated by inadequate initial antibiotic therapy. This concern however may lead to hesitance to de-escalate while awaiting pathogen identification and susceptibility results. We performed a randomized controlled trial evaluating the impact of a strategy for rapid pathogen and resistance detection directly from positive blood culture bottles (BCBs) using a rapid multiplex PCR (rmPCR) complemented with a rapid phenotypic screen (RPS) for extended-spectrum beta-lactamases and carbapenemases in a setting with moderate to high levels of antimicrobial resistance where routine direct-from-BCB disk diffusion susceptibility testing was in place Methods Patients with positive BCBs were randomized to 2 arms: 1) Standard BCB processing (including direct from BCB disk diffusion susceptibility testing - control, n=419) with antimicrobial stewardship (AS); or 2) rmPCR/RPS with AS (rmPCR/RPS, n=425). The primary outcome was time from positive blood culture result to prescription of an effective or optimal antibiotic regimen. An effective antibiotic regimen was defined as one active against the detected pathogen(s); an optimal antibiotic regimen was defined as an effective regimen which was also the most narrow spectrum and targeted one, as recommended by institutional guidelines. Mortality was analyzed as a secondary outcome. Results True bacteremia was identified in 658 patients (n=329 in both arms); 597 were monomicrobial (405 with aerobic or facultative anaerobic Gram negatives rods [AGNR]) and 61 polymicrobial (41 harboring AGNR). Time from BCB Gram stain to prescription of an effective antibiotic was 9.9 versus 3.2 hours in the control and rmPCR/RPS groups, respectively (p=0.58) and time from Gram stain to prescription of an optimal antibiotic regimen was 41.6 versus 29.4 hours in the two groups, respectively (p < 0.001). 14-day mortality was 7.6% versus 4.3% (p = 0.069) and 30-day mortality was 11.2% versus 8.8% (p=0.30) in the two groups, respectively. Conclusion Compared to control methods which included direct-from-BCB disk diffusion susceptibility testing, an intervention comprising rmPCR/RPS with AS applied to positive blood cultures improved time to optimal therapy but not time to effective therapy or mortality. Disclosures Shawn Vasoo, MBBS, MRCP, D(ABP), D(ABIM) (Inf Dis), FRCPath, bioMerieux: In-kind, for this study|Rosco Diagnostica: In-kind, for this study Robin Patel, MD, a patent on Bordetella pertussis/parapertussis PCR issued, a patent on a device/method for sonication with royalties paid by Samsung to Mayo Clinic, a: See above|MicuRx Pharmaceuticals and BIOFIRE: Grant/Research Support|PhAST, Day Zero Diagnostics, Abbott Laboratories, Sysmex, DEEPULL DIAGNOSTICS, S.L., Netflix, Oxford Nanopore Technologies and CARB-X: Advisor/Consultant|Up-to-Date and the Infectious Diseases Board Review Course.: Honoraria Paul Tambyah, MBBS (S'pore), Diplomate, American Board of Internal Medicine and Infectious Diseases, Moderna: Grant/Research Support|Sanofi-Pasteur: Grant/Research Support

Silver foam dressings have been extensively used in the management of burn injuries; however, its application in children requires elucidation. A literature search was conducted from database inception to October 2023. Eligible studies reported paediatrics patients under 21 years of age receiving silver dressings for burns or scalds. This review was registered prospectively with PROSPERO (CRD42023470239). 18 studies met the inclusion criteria with a total of 701 patients. The pooled mean time to re-epithelisation (TTRE) was 12.9 days (95% CI: 11.2, 14.6, I2 = 94%). The pooled mean duration of hospitalisation was 9.8 days (95% CI: 3.9, 15.7; I2 = 100%). Mean number of total dressing changes per patient was 3.6 (95% CI: 2.2, 4.9; I2 = 99%). There were a total of 98 complications, including 30 (30.6%) infections, 29 (29.6%) surgical requirements, 14 (14.3%) hypertrophic scarring, 17 (17.3%) escalations of care, 5 (5.1%) burn depth progression, and 3 (3.1%) others. Silver foam dressings appear as a safe and effective approach in terms of healing rate and dressing change frequency for selected paediatric patients with burn injuries. Despite the promising results, further comparative studies are required to evaluate the selection criteria and long-term effect of silver foam dressing.

Stenosis of the left main coronary artery (LM stenosis) is associated with significant mortality and morbidity due to the large area of affected myocardium. Evidence on the use of percutaneous coronary intervention (PCI) for the treatment of LM stenosis is growing. However, the role of Western guidelines on patients in the Asian-Pacific region is unclear due to anatomical variations, substantial heterogeneity in healthcare resources and infrastructure, and the lack of consensus on the optimal management of LM stenosis in the Asia-Pacific region. Hence, an Asian Pacific Society of Cardiology (APSC) working group developed consensus recommendations on the use of PCI in the management of LM stenosis in the Asia-Pacific region. The APSC expert panel reviewed and appraised the available evidence using the Grading of Recommendations Assessment, Development, and Evaluation system. Consensus recommendations were developed and put to an online vote. Consensus was reached when 80% of votes for a given recommendation were in support of ‘agree’ or ‘neutral’. The resulting 12 statements provide guidance for clinical practitioners in the region on the use of PCI in the treatment of patients with LM stenosis.