Efficacy Of Inhibitors Research Articles

Dizocilpine derivatives as neuroprotective NMDA receptor antagonists without psychomimetic side effects

We aimed to prepare novel dibenzo[a,d][7]annulen derivatives that act on N-methyl-D-aspartate (NMDA) receptors with potential neuroprotective effects. Our approach involved modifying the tropane moiety of MK-801, a potent open-channel blocker known for its psychomimetic side effects, by introducing a seven-membered ring with substituted base moieties specifically to alleviate these undesirable effects. Our in silico analyses showed that these derivatives should have high gastrointestinal absorption and cross the blood-brain barrier (BBB). Our pharmacokinetic studies in rats supported this conclusion and confirmed the ability of leading compounds 3l and 6f to penetrate the BBB. Electrophysiological experiments showed that all compounds exhibited different inhibitory activity towards the two major NMDA receptor subtypes, GluN1/GluN2A and GluN1/GluN2B. Of the selected compounds intentionally differing in the inhibitory efficacy, 6f showed high relative inhibition (∼90% for GluN1/GluN2A), while 3l showed moderate inhibition (∼50%). An in vivo toxicity study determined that compounds 3l and 6f were safe at 10 mg/kg doses with no adverse effects. Behavioral studies demonstrated that these compounds did not induce hyperlocomotion or impair prepulse inhibition of startle response in rats. Neuroprotective assays using a model of NMDA-induced hippocampal neurodegeneration showed that compound 3l at a concentration of 30 μM significantly reduced hippocampal damage in rats. These results suggest that these novel dibenzo[a,d][7]annulen derivatives are promising candidates for developing NMDA receptor-targeted therapies with minimal psychotomimetic side effects.

Macropinocytosis-targeted peptide-docetaxel conjugate for bystander pancreatic cancer treatment

Oncogenic Kirsten rat sarcoma viral oncogene homolog (KRAS) mutations are highly prevalent in pancreatic ductal adenocarcinoma (PDAC) and have garnered attention as potential target for targeted therapies, such as KRAS inhibitors. However, the limited therapeutic efficacy of KRAS allele-specific inhibitors necessitate an efficient pan-KRAS cancer cell killing strategy. Here, we have examined enhanced macropinocytosis pathway in KRAS mutant cancer cells and report improved intracellular delivery of albumin-based therapeutics. We further established an albumin-binding peptide-docetaxel conjugate platform (MPD3), which has a caspase-3 cleavable feature, for macropinocytosis-targeted bystander payload delivery and realization of bystander killing of pan-KRAS cancer cells, complemented with caspase-3 mediated activation of MPD3 to bolster tumoral accumulation of cytotoxic payloads. Utilization of in vitro co-culture system of pan-KRAS cancer cells and pharmacodynamic marker staining revealed potent bystander killing effects of MPD3, highlighting MPD3 as an efficient delivery platform against pan-KRAS cancer. Moreover, MPD3 elicited robust anti-tumor activities in both local and liver metastatic PDAC tumor models in mice. Overall, this work establishes a paradigm for developing translational pan-KRAS cancer treatment and broadens the applicability of albumin binding peptide-drug conjugate against albumin-metabolism enriched cancers.

Beyond clinical trials: CDK4/6 inhibitor efficacy predictors and nomogram model from real-world evidence in metastatic breast cancer.

CDK4/6 inhibitors (CDK4/6i) have shown promising results in the treatment of hormone receptor-positive (HR+) metastatic breast cancer (MBC) when combined with endocrine therapy (ET). It is crucial to evaluate the actual effectiveness and safety of CDK4/6i in clinical practice, as well as to analyze the factors that can predict their outcomes. Patients with HR+ MBC who received CDK4/6i-based therapy between May 2016 and May 2023 at Hunan Cancer Hospital were evaluated for progression-free survival (PFS). Adverse reactions were assessed based on the National Cancer Institute Common Toxicity Criteria (version 5.0). This study included 344 patients, with a median PFS (mPFS) of 12.8 months (range: 10.4-15.2 months). After adjustment, Cox multivariate regression analysis revealed that visceral metastasis (specifically liver and brain metastases), Eastern Cooperative Oncology Group Performance Status (ECOG PS) ≥ 1, estrogen receptor ≤ 80%, progesterone receptor ≤ 10%, Ki-67 > 30%, and treatment in later stages were significant factors associated with reduced PFS. Based on this, we created a prognostic nomogram and validated its performance, obtaining a C-index of 0.714 (95% confidence interval: 0.640-0.787) as well as reliable calibration and clinical impact. The mPFS of CDK4/6i rechallenge was 7.7 months; for patients who initially discontinued CDK4/6i for reasons other than disease progression, CDK4/6i rechallenge still provided a mPFS of 11.4 months. The tolerability and safety of combining CDK4/6is with ET were manageable. Adverse events led to treatment discontinuation in 3.8% of patients. Neutropenia (29.1%), leukopenia (13.7%), and anemia (4.1%) were the primary grade 3/4 adverse reactions. This real-world study highlights the ample efficacy and reasonable safety of combined CDK4/6i and ET in patients with HR+ MBC. Individualized treatment decisions and ongoing safety monitoring are important to optimize the therapeutic benefit of CDK4/6i treatment.

Correlation between thyroid dysfunction and efficacy of immune checkpoint inhibitors in patients with advanced solid tumors.

Immune checkpoint inhibitors (ICIs) are currently the first line of tumor immunotherapy for the treatment of a wide range of tumors. However, the main side effect of immune checkpoint inhibitors is that they cause immune-related adverse events (irAEs) in patients. The relationship between the occurrence of immune side effects in patients and efficacy is controversial. The objective of this study was to confirm the relationship between patients who develop thyroid dysfunction after immune checkpoint inhibitors and efficacy. This study was a retrospective real-world clinical study, and a total of 50 patients with advanced tumors treated with immune checkpoint inhibitors at Anqing People's Hospital from 2020.8 to 2022.5 were retrospectively collected. Among them, 30 patients with hypothyroidism and 20 patients with normal or hyperthyroidism occurred, and the treatment effects and prognostic differences between the two groups were compared. After PD1 treatment in all patients, there were 10 cases of partial remission(PR), 18 cases of stable disease(SD) and 2 cases of progressive disease(PD) in patients who developed hypothyroidism, with a disease control rate(DCR) of 93.3% and objective remission rate(ORR) of 33.3%. There were 0 complete remission (CR) patient, 3 PR patients, 11 SD patients, 6 PD patients, 70.0% DCR and 15.0% ORR in patients who did not develop hypothyroidism. The DCR and ORR of patients who developed hypothyroidism were better than those of non-hypothyroid patients, and the difference was statistically significant (P < 0.05). Kaplan-Meier survival analysis showed that progression-free survival (PFS) reached 9.2months (95% CI 7.726-10.779) in patients who developed hypothyroidism and did not hypothyroidism patients have a PFS of 7.3months (95% CI 5.604-8.505), with a statistically significant difference (P = 0.0341 < 0.05). Further subgroup analysis revealed that among patients who developed hypothyroidism, PFS was 3.3months (95% CI 0.630-5.440) in patients with cholangiocarcinoma, 6.89months (95% CI 5.604-8.505) in patients with non-small cell lung cancer, > 12months in patients with hepatocellular carcinoma, and 11.05months (95% CI 9.308-12.792) in patients with esophageal cancer months and PFS for patients with gastric cancer was 9.74months (95% CI 6.979-12.502). When patients with advanced tumors were treated with immune checkpoint inhibitors, DCR and ORR were higher in patients who developed hypothyroidism, and patients had better PFS. The benefits were greater in patients with gastric, esophageal, and hepatocellular carcinomas.

Targeting the mTOR-Autophagy Axis: Unveiling Therapeutic Potentials in Osteoporosis

Osteoporosis (OP) is a widespread age-related disorder marked by decreased bone density and increased fracture risk, presenting a significant public health challenge. Central to the development and progression of OP is the dysregulation of the mechanistic target of the rapamycin (mTOR)-signaling pathway, which plays a critical role in cellular processes including autophagy, growth, and proliferation. The mTOR-autophagy axis is emerging as a promising therapeutic target due to its regulatory capacity in bone metabolism and homeostasis. This review aims to (1) elucidate the role of mTOR signaling in bone metabolism and its dysregulation in OP, (2) explore the interplay between mTOR and autophagy in the context of bone cell activity, and (3) assess the therapeutic potential of targeting the mTOR pathway with modulators as innovative strategies for OP treatment. By examining the interactions among autophagy, mTOR, and OP, including insights from various types of OP and the impact on different bone cells, this review underscores the complexity of mTOR’s role in bone health. Despite advances, significant gaps remain in understanding the detailed mechanisms of mTOR’s effects on autophagy and bone cell function, highlighting the need for comprehensive clinical trials to establish the efficacy and safety of mTOR inhibitors in OP management. Future research directions include clarifying mTOR’s molecular interactions with bone metabolism and investigating the combined benefits of mTOR modulation with other therapeutic approaches. Addressing these challenges is crucial for developing more effective treatments and improving outcomes for individuals with OP, thereby unveiling the therapeutic potentials of targeting the mTOR-autophagy axis in this prevalent disease.

Clinical advances and challenges in targeting FGF/FGFR signaling in lung cancer.

Fibroblast growth factors (FGFs) and their receptors regulate numerous cellular processes, such as metabolism and signal transduction, but can also drive tumorigenesis. Specifically, in lung cancer, the overexpression of FGFs, as well as the amplification, mutation and fusion of FGFR genes, are closely linked to the initiation, progression and resistance of the disease, suggesting that targeting FGF/FGFR is an attractive therapeutic strategy for lung cancer treatment. Nintedanib, a multitarget tyrosine kinase inhibitor (TKI) used in combination with docetaxel, has shown some success as a second-line therapy for lung cancer. However, clinical trials evaluating other FGFR inhibitors have yielded mixed results, indicating substantial complexity in targeting aberrant FGF/FGFR signaling. In this review, we describe the aberrations in FGF/FGFR signaling in lung cancer and summarize the clinical efficacy of FGFR inhibitors, such as multitarget TKIs, selective FGFR-TKIs and biological agents. We also discuss various challenges associated with FGFR targeting in lung cancer, including precision patient selection, toxicity and resistance. Finally, we provide perspectives on future directions, namely, developing novel FGFR-targeting drugs, such as FGFR degraders and more specific FGFR-TKIs, adopting combination therapy and targeting FGFs.

Rapid response of lichen planus to baricitinib associated with suppression of cytotoxic CXCL13+ CD8+ T-cells.

Cutaneous lichen planus (LP) is a recalcitrant, difficult-to-treat, inflammatory skin disease characterized by pruritic, flat-topped, violaceous papules on the skin. Baricitinib is an oral Janus kinase (JAK) 1/2 inhibitor that interrupts the signaling pathway of interferon gamma (IFN)-γ, a cytokine implicated in the pathogenesis of LP. In this phase II trial, twelve patients with cutaneous LP received baricitinib 2 mg daily for 16 weeks, accompanied by in-depth spatial, single-cell, and bulk transcriptomic profiling of pre- and post-treatment samples. An early and sustained clinical response was seen, with 83.3% of patients responsive at week 16. Our molecular data identified a unique, oligoclonal IFN-γ, CD8+, CXCL13+ cytotoxic T-cell population in LP skin and demonstrated a rapid decrease in IFN signature within 2 weeks of treatment, most prominently in the basal layer of the epidermis. This study demonstrates the efficacy and molecular mechanisms of JAK inhibition in LP. NCT05188521.ROLE OF FUNDING SOURCE. Eli Lilly, Appignani Benefactor Funds, 5P30AR075043, Mayo Clinic Clinical Trials Stimulus Funds.

Safety and efficacy of IL-17 inhibitors in hidradenitis suppurativa: an updated systematic review and meta-analysis including the BE-HEARD trials.

Safety and efficacy of IL-17 inhibitors in hidradenitis suppurativa: an updated systematic review and meta-analysis including the BE-HEARD trials.

Dysregulation of deubiquitinases in gastric cancer progression

Gastric cancer (GC), characterized by a high incidence rate, poses significant clinical challenges owing to its poor prognosis despite advancements in diagnostic and therapeutic approaches. Therefore, a comprehensive understanding of the molecular mechanisms driving GC progression is crucial for identifying predictive markers and defining treatment targets. Deubiquitinating enzymes (DUBs), also called deubiquitinases, function as reverse transcriptases within the ubiquitin-proteasome system to counteract protein degradation. Recent findings suggest that DUB dysregulation could be a crucial factor in GC pathogenesis. In this review, we examined recent research findings on DUBs in the context of GC, elucidating their molecular characteristics, categorizations, and roles while also exploring the potential mechanisms underlying their dysregulation in GC. Furthermore, we assessed the therapeutic efficacy of DUB inhibitors in treating malignancies and evaluated the prevalence of aberrant DUB expression in GC.

Comprehensive analysis of single-cell and bulk RNA sequencing reveals postoperative progression markers for non-muscle invasive bladder cancer and predicts responses to immunotherapy.

Non-muscle-invasive bladder cancer (NMIBC) is renowned for its high recurrence, invasiveness, and poor prognosis. Consequently, developing new biomarkers for risk assessment and investigating innovative therapeutic targets postoperative in NMIBC patients are crucial to aid in treatment planning. Differential gene expression analysis was performed using multiple Gene Expression Omnibus (GEO) datasets to identify differentially expressed genes (DEGs) between NMIBC and normal tissue, as well as between NMIBC and muscle-invasive bladder cancer (MIBC). Functional enrichment analysis was conducted based on the DEGs identified. Subsequently, prognosis-related genes were selected using Kaplan-Meier (KM) analysis and Cox regression analysis. The Boruta algorithm was utilized to further screen for core DEGs related to postoperative progression in NMIBC based on the aforementioned prognosis-related genes. Single-cell and clinical correlation studies were performed to verify their expression across various stages of bladder cancer. To investigate the link between core genes and the immune microenvironment, single-sample gene set enrichment analysis (ssGSEA) was utilized, and Receiver Operating Characteristic (ROC) and KM analyses were performed to confirm predictive power for immune therapy outcomes. Machine learning (ML) models were constructed using the DepMap dataset to predict the efficacy of core gene inhibitors in treating bladder cancers. The prognostic performance of the core genes was evaluated using ROC curve analysis. An online prediction tool was developed based on the core genes to provide prognostic predictions. Finally, RT-qPCR, CCK-8, and Transwell assays were used to verify the pro-tumor effects of the GINS2 in bladder cancer. A total of 70 DEGs were identified, among which 11 prognostic genes were obtained through KM analysis, and an additional 8 prognostic genes were obtained through COX analysis. The Boruta algorithm selected AURKB, GINS2, and UHRF1 as the three core DEGs. Single-cell and clinical variable correlation analyses indicated that the core genes promoted the progression of bladder cancer. The analysis of immune infiltration revealed a strong positive association between the core genes and both activated CD4 T cells and Type 2 helper T cells. Two random forest (RF) models were constructed to effectively predict the treatment effect of bladder cancer after targeted inhibition of AURKB and GINS2. In addition, an online nomogram tool was developed to effectively predict the risk of postoperative progression in NMIBC patients undergoing TURBT. Finally, RT-qPCR, CCK8, and Transwell assays showed that GINS2 promoted the growth and progression of bladder cancer. AURKB, GINS2, and UHRF1 have the potential to enhance postoperative management of NMIBC patients undergoing transurethral resection of bladder tumor (TURBT) and can predict immunotherapy response, establishing them as promising therapeutic targets.

Abstract 4147610: Efficacy and Safety of Selective Cardiac Myosin Inhibitors in Symptomatic Hypertrophic Obstructive Cardiomyopathy: A Meta-Analysis of Randomized Controlled Trials

Background: Hypertrophic Obstructive Cardiomyopathy (HOCM) is an autosomal dominant inherited condition with limited management options, primarily focusing on symptom improvement through beta blockers. A novel selective cardiac myosin inhibitor, Mavacamten has been shown to improve exercise tolerance and NYHA functional class as compared to placebo in multiple randomized controlled trials (RCTs). A recent RCT from 2024 studied another oral cardiac myosin inhibitor, Aficamten which potentially decreases left ventricular outflow tract obstruction (LVOTO) in symptomatic HOCM. One limitation of all these RCTs, for obvious reasons, is the small sample size, which poses a challenge in its actual clinical significance. Aims: To analyze the efficacy and safety of novel selective cardiac myosin inhibitors in symptomatic HOCM patients Methods: We included 4 RCTs, comparing the efficacy and safety of selective cardiac myosin inhibitors and placebo groups. These studies were selected through a detailed search of the MEDLINE, COCHRANE, and PUBMED databases. We compared various common primary and secondary endpoints between both the groups: changes in exercise tolerance, NYHA functional class, and Kansas City Cardiomyopathy Questionnaire-Clinical Summary Score (KCCQ-CSS). The results were reported as Odds Ratios (OR) with 95% confidence intervals (CI), using a random effects model. Results: The outcomes from 704 HOCM patients, which consisted of 361 patients who received a myosin inhibitor and 343 who received a placebo were analyzed. The primary endpoint in all the studies was improvement in exercise tolerance [measured as 1.5 mL/kg per min or greater increase in peak oxygen consumption (pVO2)], which was not statistically significant in our study (OR: 1.75, 95% CI: 0.89-3.43, p:0.1). There was a statistically significant improvement in ≥1 NYHA functional Class (OR: 3.9, 95% CI:2.49-6.12 p&lt;0.05). There was no significant change seen in KCCQ-CSS (OR: 1.26, 95% CI: 0.75-2.12, p:0.3) and1 or more Serious Adverse Events (OR: 0.75, 95% CI: 0.42-1.32, p:0.3). (Figures A-D) Conclusion: Novel cardiac myosin inhibitors have shown statistically significant results in improving NYHA functional class, but not much difference in objective criteria like pVO2 with no significant adverse events. While these results appear promising and 2024 ACC/AHA guidelines have Class 1 Recommendation regarding their use for symptomatic HOCM, further analysis from a large population is needed.

Efficacy and safety of complement inhibitors in patients with geographic atrophy associated with age-related macular degeneration: a network meta-analysis of randomized controlled trials

ImportanceClinical trials in recent years have shown significant effectiveness of complement inhibitors for geographic atrophy (GA) treatment. Two complement inhibitor drugs have been approved by the Food and Drug Administration (FDA).Objectiveto compare and rank the different complement inhibitors in the treatment of GA secondary to age-related macular degeneration (AMD).Data sourcesA systematic literature search was conducted in the Cochrane Central, Web of Science Core Collection, PubMed, LWW Medical Journals, ClinicalTrials.gov, and WHO ICTRP from inception to October 2023.Study selectionAll randomized clinical trials evaluating the effectiveness of complement inhibitors in patients diagnosed with secondary GA in AMD were identified.Data extraction and synthesisThis study followed Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) network meta-analysis Checklist of Items and the Cochrane Risk of Bias Assessment Tool for assessing the study quality. Multiple authors independently coded all titles and abstracts, reviewed full-text articles against the inclusion and exclusion criteria, and resolved all discrepancies by consensus. Random-effects network meta-analyses were applied. Bayesian network meta-analysis was performed using the BUGSnet package in R (4.2.0).Main outcomes and measuresThe primary efficacy outcome was the change in GA lesion size (mm2) from baseline to month 12. The secondary efficacy outcome was the mean change in best-corrected visual acuity (BCVA) from baseline to month 12. Safety outcome measures included the number of subjects with serious adverse events (SAEs) and macular neovascularization (MNV).ResultsTen randomized controlled trials including 4,405 participants and five complement inhibitors were identified. Comparison with sham and SUCRA analysis showed that avacincaptad pegol 2 mg (MD: −0.58, 95% CrI: −0.97 to −0.18, SUCRA: 93.55), pegcetacoplan monthly (MD: −0.38, 95% CrI: −0.57 to −0.20, SUCRA: 81.37), and pegcetacoplan every other month (MD: −0.30, 95% CrI: −0.49 to −0.11, SUCRA: 70.16) have significant changes in GA lesion reduction. No treatments showed significant changes in BCVA and SAE compared with sham. Pegcetacoplan monthly (OR: 4.30, 95% CrI: 1.48–16.72) increased the risk of MNV. Avacincaptad pegol 2 mg demonstrated favorable outcomes in terms of SAE and MNV.Conclusion and relevanceAvacincaptad pegol 2 mg is the most effective complement inhibitor with better safety for the treatment of GA secondary to AMD.Systematic Review Registrationhttps://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022351515, Identifier PROSPERO CRD42022351515.

Abstract 4135465: Efficacy of SGLT-2 inhibitors combined with percutaneous coronary intervention on clinical and echocardiographic parameters in patients with acute myocardial infarction: A systematic review and meta-analysis

Background: Sodium-glucose cotransporter 2 inhibitors (SGLT2i) have shown benefits in improving cardiovascular outcomes in heart failure (HF) patients and may mitigate symptom progression in myocardial infarction (MI). However, their efficacy in acute MI patients undergoing percutaneous coronary intervention (PCI) is unclear. This study aims to evaluate whether SGLT2i combined with PCI improves clinical and echocardiographic outcomes. Methods: A comprehensive search of electronic databases, PubMed, Cochrane Central and SCOPUS was conducted from inception till May 2024. The study was conducted adhering to the PRISMA guidelines. The clinical benefit of PCI plus SGLT2i was assessed through risk reduction of acute kidney injury (AKI), CV death (CVD), hospitalization due to HF (hHF), all-cause mortality (ACM), and revascularization. Echocardiographic outcomes assessed were change in left ventricular ejection fraction (LVEF) and LV end-diastolic volume (LVEDV). Results were presented as risk ratios (RR) along with their 95% CI for dichotomous data while weighted mean difference (WMD) were reported for continuous outcomes. The data was aggregated using a random effects model. Results: Our analysis included eleven records comprising 6,411 participants. The results indicated that PCI plus SGLT2i significantly reduced the risk of AKI (RR: 0.66, 95% CI: [0.52, 0.83], p&lt;0.01) and ACM (RR: 0.54, 95% CI: [0.4, 0.7], p&lt;0.01) compared to PCI alone. However, the reduction in risk for CVD was not statistically significant (RR: 0.56, 95% CI: [0.2, 1.1], p=0.09), as was the case for hHF (RR: 0.65, 95% CI: [0.3, 1], p=0.07). Additionally, there was no significant difference in the risk of revascularization between the two groups (RR: 2.9, 95% CI: [0.62, 14.39], p=0.17). PCI plus SGLT2i was also significantly associated with an increase in LVEF (WMD: 2.73, 95% CI: [1.09, 4.36], p&lt;0.01) and decrease in LVEDV (WMD: -8.0, 95% CI: [-13.17, -2.90], p&lt;0.02). Conclusion: Our study demonstrates that SGLT2i administration in MI patients undergoing PCI leads to improved renal and mortality outcomes, along with enhanced cardiac function. These benefits are hypothesized to result from kidney-mediated natriuretic effects, improved blood flow regulation, reduced endothelial dysfunction, and decreased arterial stiffness, which optimize cardiac function. We recommend future studies with larger sample sizes and longer follow-ups to assess the long-term benefits of SGLT2i combined with PCI.

Corrigendum: Field efficacy of urease inhibitors for mitigation of ammonia emissions in agricultural field settings: a systematic review

Corrigendum: Field efficacy of urease inhibitors for mitigation of ammonia emissions in agricultural field settings: a systematic review

Enhanced corrosion protection of copper in saline environments using bio-nanocomposite coatings based on chitosan and chitosan Schiff base

An in-depth study focuses on developing new environmentally friendly bio-nanocomposites, by incorporating SrTiO3 (STO) ceramic nanoparticles into matrices of chitosan and its derivatives, aiming to use them as protective coatings against corrosion. The various stages of this study include the cross-linking of chitosan, the synthesis of Schiff base chitosan, the cross-linking of Schiff base chitosan, and the preparation of nanocomposite coatings. The coatings' structure and composition were analyzed using different methods, including Fourier Transform Infrared Spectroscopy - Attenuated Total Reflectance (FTIR-ATR), X-ray Diffraction (XRD), Transmission Electron Microscopy coupled with Energy Dispersive X-ray Spectroscopy (TEM-EDX), and Scanning Electron Microscopy (SEM). In addition, Electrochemical Impedance Spectroscopy (EIS) and Potentiodynamic Polarization (PDP) measurements were carried out to assess the inhibitory efficacy of chitosan crosslinked with epichlorohydrin (Cs-Ep), epichlorohydrin-crosslinked chitosan-salicylaldehyde Schiff base (CS-S-Ep) and CS-Ep-STO and CS-S-Ep-STO nanocomposite coatings, as well as the long-term protection durability of CS-S-Ep-STO. These techniques revealed a significant reduction in corrosion current density after chemical modification of chitosan and incorporation of SrTiO3 (STO) nanoparticles into CS-Ep and CS-S-Ep matrices, confirming a notable improvement in the inhibitory efficiency of these coatings against copper corrosion in a saline environment. Computational modeling methods like Density Functional Theory (DFT), Molecular Dynamics (MD), and Monte Carlo (MC) simulations reinforced these results by demonstrating efficient adsorption of CS-S-Ep-STO nanocomposites on metal surfaces through the interaction with heteroatoms present in the functional groups (-C=N-, -C-O-, -OH) and STO nanoparticles. The present study's findings provide key information for developing innovative protective coatings, highlighting the potential of chitosan-based nanocomposites and derivatives, particularly with SrTiO3 incorporation, in mitigating metal surface corrosion in aggressive environments.

EXTH-44. ENHANCING THERAPEUTIC APPROACHES IN HIGH-GRADE GLIOMAS: SYNERGISTIC EFFECTS OF LSD1 AND KINASE INHIBITION

Abstract BACKGROUND Glioblastoma (GBM) and Diffuse Intrinsic Pontine Glioma (DIPG) are devastating high-grade gliomas (HGGs) with poor prognoses. Lysine-specific demethylase 1 (LSD1) is a promising therapeutic target and a key regulator in tumor initiation and recurrence. Crosstalk between LSD1 and other signaling pathways, such as the MAPK pathway, frequently hyperactivated in HGG, offers an opportunity to enhance the efficacy of LSD1 inhibitors. This study investigates the combined inhibition of LSD1 and kinase signaling to improve therapeutic outcomes in HGG. METHODS Transcriptional changes following LSD1 knockdown in human GBM cells were analyzed using RNA-seq and GSEA. RPPA and western blotting assessed the impact of LSD1 inhibition on kinase signaling. Pharmacological LSD1 inhibition was tested using NCD38 or bomedemstat in HGG models and normal human astrocytes (NHA). The effects of combining LSD1 inhibitors with kinase inhibitors (osimertinib, afatinib, and ulixertinib) on cell viability were evaluated. Combination treatment was also assessed in orthotopic xenograft models of GBM. RESULTS GSEA revealed LSD1 expression was enriched for gene sets involved in kinase signaling processes. Increased phosphorylated ERK1/2 levels were observed following NCD38 treatment in MDA-GSC17, as shown by RPPA and western blot analyses. The LSD1 inhibitor, NCD38, increased phospho-ERK1/2 levels (72% increase from baseline), while co-treatment with osimertinib mitigated this effect. Combined LSD1 and kinase inhibition (EGFR and ERK inhibition) showed synergistic effects in vitro in GBM and DIPG models but not in the NHA. DISCUSSION Our results demonstrate that kinase activity can be modulated by inhibiting LSD1, potentially leading to a resistant subpopulation. This study underscores the potential of combining LSD1 and kinase inhibition to enhance therapeutic efficacy in HGG, including GBM and DIPG. Future research will focus on elucidating the mechanisms by which LSD1 regulates kinase signaling, aiming to optimize combination therapies.

DDDR-26. IDENTIFICATION OF MODULATORS OF IDH INHIBITOR SENSITIVITY INIDH-MUTATED DIFFUSE GLIOMAS

Abstract Driver mutations in IDH1 and IDH2 characterize a substantial proportion of lower-grade diffuse gliomas in adults. Mutated IDH molecules cause the accumulation of D-2-hydroxyglutarate (D-2-HG), which perturbs many cellular functions, including metabolism, epigenetic regulation, and the ability to differentiate. This is notably associated with DNA and histone hyper-methylation. Recently, the newly developed IDH inhibitor, vorasidenib, was shown to delay tumor progression and the need for additional treatment in the groundbreaking INDIGO clinical trial. Nevertheless, the responses to vorasidenib were variable between patients, and so far have been established only for less aggressive disease. In addition, it is unclear to what extent vorasidenib can cause tumor regression. This highlights the need to identify molecules and pathways that control IDH inhibitor sensitivity. Towards this goal, we generated a new mouse model that combines Idh1R132H and Trp53 loss-of-function, targeted to oligodendrocyte progenitors. All the mutant mice develop diffuse gliomas that recapitulate the cardinal features of the corresponding human disease. We established multiple cell lines from these tumors, which retained expression of mutant IDH. The cells robustly produced D-2-HG, which was concentration-dependently suppressed by vorasidenib. Accordingly, vorasidenib could lower DNA methylation, and induce the expression of mature glial cell markers. To identify determinants of vorasidenib sensitivity, we performed genome-wide loss-of-function CRISPR/Cas9 functional genomics screens. In those experiments, targeting genes associated with astrocyte differentiation or Notch signaling enhanced cell fitness in the presence of vorasidenib, consistent with the anticipated effects of the drug on inducing cell differentiation. Conversely, vorasidenib-treated cells were more sensitive to the loss of regulators of cell growth and metabolism, and of some epigenetic regulators. These studies point to strategies that may enhance the efficacy of IDH inhibitors for the treatment of IDH mutated gliomas.

IMMU-64. SEX-SPECIFIC ROLES OFYAP1 AND CD276/B7-H3 IN MEDULLOBLASTOMA IMMUNE SUPPRESSION

Abstract The molecular mechanism governing sex disparities in cancer prevalence, progression, and treatment outcomes represents an important yet understudied area of research with significant implications for cancer treatment. Medulloblastoma (MB), the most prevalent pediatric brain malignancy, exhibits a notable sex bias in incidence and survival rates. Males have a higher incidence rate across all age groups and have worse prognoses than their females for age groups over three years old. Here, we report an unanticipated sex-biased role of the oncogene Yap1 in SHH medulloblastoma. Our results reveal that Yap1 deletion significantly prolongs survival in male, but not female mice with SmoM2-driven SHH MB. Employing an integrated multi-omics approach, we demonstrate that YAP1 is required to maintain cancer stem cells simultaneously activating stemness genes (such as Sox2) and repressing differentiation genes (such as Neurod1 and Zic1/2) in both sexes. In contrast, Yap1 plays a more critical role in immune evasion in males than in females. Specifically, YAP1 regulates the expression of the immune checkpoint molecule Cd276/B7-H3, which suppresses cytotoxic T cell function. In males, CD276 blockade or Yap1 deletion in MB cells is enough to reverse T cell suppression effectively. In females, neither CD276 blockade nor Yap1 deletion alone in MB cells can reverse T cell suppression. Furthermore, YAP1’s direct transcriptional target gene signatures, including CD276, predict survival across multiple human cancers in male patients. These findings suggest broader implications of our findings beyond medulloblastoma and indicate a highly conserved mechanism across species. Our study provides compelling evidence for the male-biased efficacy of Yap1 or CD276 inhibitors and presents novel insights into sex-specific mechanisms of cancer immune evasion.

DDDR-41. A GENOME-WIDE CRISPR/CAS9 SCREEN IN GLIOBLASTOMA STEM CELLS UNVEILS SYNTHETIC LETHAL INTERACTIONS AND RESISTANCE MECHANISMS OF JIN001, A BLOOD-BRAIN BARRIER-PENETRANT HSP90 INHIBITOR

Abstract Glioblastomas (GBMs) are aggressive brain tumors characterized by extensive genetic heterogeneity and therapeutic resistance. Heat shock protein 90 (Hsp90) is a molecular chaperone that stabilizes and facilitates the proper folding of numerous proteins, including oncogenic drivers and is overexpressed in cancers. Hsp90 inhibitors can disrupt multiple oncogenic signaling pathways by degrading various client proteins essential for tumor growth and survival, making them attractive therapeutic candidates for GBMs. We have previously reported on the efficacy of Hsp90 inhibitors against gliomas. However, cancer cells develop resistance to Hsp90 inhibitors by upregulating compensatory chaperones (e.g., Hsp70), mutating client proteins, or activating alternative survival pathways, reducing the long-term efficacy of these agents. Combination approaches overcoming such resistance mechanisms are needed. JIN001, a novel Hsp90 inhibitor, demonstrates superior blood-brain barrier (BBB) penetration, and high potential for clinical translation. we performed a genome-wide CRISPR/Cas9 knockout screen using the Toronto Knockout Library v3 (TKOv3) with screen selection pressure from JIN001 in GBM stem cells (GSC272) to identify synthetic lethal interactions and resistance mechanisms associated with JIN001 treatment. Experiments were performed in triplicate with two time points, T22 and T37. Quality control analysis of the NGS data indicated excellent quality and consistency between different replicates. DrugZ analysis revealed a set of sensitive and resistant genes, informing potential combination therapies and further elucidating JIN001’s mechanism of action. Validation studies for the top synthetic lethal targets are underway to confirm the identified interactions and will be presented. This CRISPR-Cas9 screen offers valuable insights into JIN001’s therapeutic potential, reveals new combination strategies to overcome resistance to Hsp90 inhibitors and for use of these agents in other cancers, and paves the way for the development of more effective GBM combination treatment strategies.

BIOM-65. ELEVATED MMP9 EXPRESSION IN ADHERENT AND LARGE VESTIBULAR SCHWANNOMAS: A PROMISING THERAPEUTIC TARGET

Abstract Vestibular schwannoma (VS) is the most common tumor of the cerebellopontine angle affecting up to 1 in 2000 adults and presents significant treatment challenges, especially when the tumor is adherent to the brainstem and cranial nerves. These tumors often require complex surgeries with high risks of complications such as hearing loss, facial paralysis, and incomplete tumor resection. Previous studies have linked immune cell infiltration and protease activation to aggressive VS. MMP9, a protease involved in extracellular matrix (ECM) remodeling, is associated with cancer invasion and progression, suggesting its potential as a biomarker and therapeutic target. This study explores whether MMP9 can classify VS and improve surgical outcomes. METHODS Fresh tumors were collected from patients undergoing surgery to establish primary VS cultures. Transcriptomic profiling was performed to examine expression of genes related to ECM remodeling, protease activation, and immune cell infiltration. MMP9 expression during schwannoma progression was validated using immunofluorescence staining and ELISA. Transwell invasion assays were performed to evaluate the role of MMP9 in schwannoma invasion. The efficacy of small molecule inhibitors against eIF4F (a transcription factor that binds to 5’ UTR of MMP9) and against MMP9 was tested in a mouse model of schwannoma. RESULTS MMP9 was the most abundantly expressed protease in VS. MMP9 expression increased with tumor size, and was higher in adherent than non-adherent VS (49.7 vs. 13.8 ng/mL, p=0.014). MMP9 expression was abundant in perivascular regions in adherent VS. Inhibition of eIF4F reduced schwannoma cell invasion mediated by MMP9.MMP9 inhibition in vivo- reduced tumor burden by 50% in mice. CONCLUSIONS MMP9 is a highly active protease in VS growth and adherent VS. Developing MMP9-targeted therapies could be a breakthrough in managing these challenging tumors.