Development of an online calculator for the prediction of seizure freedom following pediatric hemispherectomy using the Hemispherectomy Outcome Prediction Scale (HOPS)
AbstractObjectivesAlthough hemispheric surgeries are among the most effective procedures for drug‐resistant epilepsy (DRE) in the pediatric population, there is a large variability in seizure outcomes at the group level. A recently developed HOPS score provides individualized estimation of likelihood of seizure freedom to complement clinical judgement. The objective of this study was to develop a freely accessible online calculator that accurately predicts the probability of seizure freedom for any patient at 1‐, 2‐, and 5‐years post‐hemispherectomy.MethodsRetrospective data of all pediatric patients with DRE and seizure outcome data from the original Hemispherectomy Outcome Prediction Scale (HOPS) study were included. The primary outcome of interest was time‐to‐seizure recurrence. A multivariate Cox proportional‐hazards regression model was developed to predict the likelihood of post‐hemispheric surgery seizure freedom at three time points (1‐, 2‐ and 5‐ years) based on a combination of variables identified by clinical judgment and inferential statistics predictive of the primary outcome. The final model from this study was encoded in a publicly accessible online calculator on the International Network for Epilepsy Surgery and Treatment (iNEST) website (https://hops‐calculator.com/).ResultsThe selected variables for inclusion in the final model included the five original HOPS variables (age at seizure onset, etiologic substrate, seizure semiology, prior non‐hemispheric resective surgery, and contralateral fluorodeoxyglucose–positron emission tomography [FDG‐PET] hypometabolism) and three additional variables (age at surgery, history of infantile spasms, and magnetic resonance imaging [MRI] lesion). Predictors of shorter time‐to‐seizure recurrence included younger age at seizure onset, prior resective surgery, generalized seizure semiology, FDG‐PET hypometabolism contralateral to the side of surgery, contralateral MRI lesion, non‐lesional MRI, non‐stroke etiologies, and a history of infantile spasms. The area under the curve (AUC) of the final model was 73.0%.SignificanceOnline calculators are useful, cost‐free tools that can assist physicians in risk estimation and inform joint decision‐making processes with patients and families, potentially leading to greater satisfaction. Although the HOPS data was validated in the original analysis, the authors encourage external validation of this new calculator.
Loss of LncRNA DUXAP8 synergistically enhanced sorafenib induced ferroptosis in hepatocellular carcinoma via SLC7A11 de‐palmitoylation
AbstractBackgroundFerroptosis is an important iron‐dependent form of cell death in hepatocellular carcinoma (HCC). Sorafenib, a potent ferroptosis inducer, is used to treat advanced HCC but its efficacy is limited by the development of drug resistance.MethodsThe effects of DUXAP8 expression on HCC progression were evaluated by TCGA database, Kaplan‐Meier analysis, and in situ hybridization analysis. Sorafenib resistant HCC cell lines were modeled in vitro to study the regulation of DUXAP8 on ferroptosis in HCC induced by sorafenib. We used RNA pull‐down, immunofluorescence assays, acyl‐biotinyl exchange assay and mass spectrometry analysis to assess the molecular mechanism of ferroptosis regulation by DUXAP8. Syngeneic subcutaneous and orthotopic CDX models were used to assess whether DUXAP8 inhibition improves HCC in vivo.ResultsLncRNA DUXAP8, which is highly expressed in liver cancer and associated with poor prognosis, contributes to sorafenib resistance through suppression of ferroptosis. In vitro tests revealed that DUXAP8 reduced the sensitivity of HCC to sorafenib‐induced ferroptosis by acting on SLC7A11, a subunit of the amino acid antiporter system xc‐. DUXAP8 facilitates SLC7A11 palmitoylation and impedes its lysosomal degradation, thereby enhancing SLC7A11 action and suppressing ferroptosis. RNA pull‐down and immunofluorescence assays confirmed that DUXAP8 decreased membrane translocation and promoted sorting of de‐palmitoylated SLC7A11 to lysosomes by binding of DUXAP8 to SLC7A11. In addition, mass spectrometric analysis found that the Cys414 residue of SLC7A11 might be the predominant mutant site responsible for molecular masking of SLC7A11 lysosomal sorting. Further, the antitumor effect of DUXAP8 knockdown was verified in orthotopic and subcutaneous CDX models.ConclusionsOur findings suggest that a novel translational strategy combining sorafenib with DUXAP8 silencing to overcome drug resistance may improve treatment efficacy in patients with advanced HCC.
Incident atrial functional mitral regurgitation in atrial fibrillation and sinus rhythm
Abstract Funding Acknowledgements Type of funding sources: None. Background Atrial functional mitral regurgitation (AFMR) has been associated with atrial fibrillation (AF) and heart failure with preserved ejection fraction. However, data on its incidence, risk factors, and clinical outcomes are scarce. Objective We aimed to study the incidence, risk factors and clinical significance of AFMR, defined as >mild functional MR in the absence of more than mild left ventricle enlargement or dysfunction, in AF and sinus rhythm (SR). Methods Adults with a new diagnosis of AF between 2010–2021 who had a transthoracic echocardiogram (TTE) were identified (n=57,109). Similarly, adults with no diagnosis of AF who had a TTE between 2010–2021 were identified for comparison (n= 364,767). Patients with >mild MR at baseline, primary mitral valve disease, cardiomyopathy, ≥moderate aortic valve disease, current or previous low ejection fraction, enlarged left ventricle, cardiac devices, previous cardiac surgeries, or with no follow up TTE ≥6 months from baseline were excluded. Furthermore, patients with AF had to have a TTE within 1 month of AF diagnosis. The presence of ≥2 of 4 abnormal diastolic function parameters [mitral septal e’ <0.07 m/sec, mitral septal E/e’ >15 in SR and >11 in AF, TR velocity >2.80 m/sec, left atrial volume index >34 ml/m2] was determined. Cox proportional hazards regression was used to determine risk factors associated with incident AFMR and all-cause death. Patients without the event of interest were censored at last follow up. Patients who developed >mild MR of other types (primary or functional ventricular) were censored at that time. Results Overall, 1,747 (median age 67 years; 34% females) patients with AF and 29,623 (median age 59; 51% females) in SR were included. Incident AFMR occurred in 167 patients with AF over median 3.1 (IQR 1.6–5.1) years [incidence rate of 2.6 per 100-person year] and in 780 patients in SR over median 3.1 (IQR 1.5–5.8) years [incidence rate 0.7 per 100-person year] (Figure 1). AF remained associated with AFMR after adjusting to confounding factors [age ≥65, female sex, ≥2 abnormal diastolic function parameters, and low hemoglobin; adjusted HR 3.23 (2.71–3.85)]. Independent risk factors associated with incident AFMR in AF were age ≥65, female sex, persistent AF, and ≥2 abnormal diastolic function parameters, whereas successful rhythm control without recurrence was a protective factor (Figure 2a). Risk factors for AFMR in SR were age ≥65 years, female sex, presence of ≥2 abnormal diastolic function parameters, and low hemoglobin (Figure 2a). Incident AFMR was independently associated with all-cause death in both AF and SR (Figure 2b). Conclusions AF confers more than 3-fold increase in the risk of AFMR. Diastolic dysfunction, older age, and female sex were independent risk factors for incident AFMR in both SR and AF. Paroxysmal AF and successful rhythm control were protective factors against AFMR in AF. AFMR is universally associated with worse mortality.
Personalizing Approaches to Patient Education Throughout the Radiation Oncology Workflow
Abstract 14719: Erk5 S496 Phosphorylation, but Not Erk5 Kinase Activation, Promotes Senescence-Associated Cell Growth (sacg) and Inflammation of Myeloid Cells and Atherosclerosis via Upregulating Sumoylation at a Novel Site (k518) on Nrf2 and Aryl Hydrocar
Senescence induced by various stresses reprograms cancer cells to acquire senescence-associated (SA) cell growth (SACG), which allows them to escape senescence-induced cell cycle arrest with enhanced growth potential. ERK5 is a dual kinase-transcription factor, containing an N-terminal kinase domain and transactivation domains in the C-terminal half. Recent data have raised questions regarding the functional role of ERK5 kinase inhibitors in cancer and inflammatory diseases. We aimed to investigate how ERK5 reprograms myeloid cells (MC) to the SA secretory phenotype (SASP) and SACG, consequently leading to atherosclerosis (AthS). AthS was inhibited in ERK5 S496A knock-in (KI) mice. Single-cell analysis of p53 and Ki67 with imaging mass cytometry revealed three groups of MCs with different p53 and Ki67 expression patterns in the plaque. One group showed that p53 and Ki67 were co-expressed lineally, suggesting that this group of cells escaped from the growth-suppression effects of p53, which is also known as a senescence marker. The % of ERK5 S496A KI cells in this group was significantly lower than in wild-type (WT). Also, we found an increase of SA β-gal (SAβ-gal) + Ki67 + and 53BP1 + Ki67 + cells in bone narrow-derived macrophage (BMDMs) isolated from hypercholesterolemia (H-chol) WT mice, suggesting H-chol-induced MC SACG. MC SACG were significantly inhibited in ERK5 S496A KI mice, supporting the role of ERK5 S496 phosphorylation on SACG. RNA sequencing analysis identified the ERK5 S496 phosphorylation-dependent AHR induction by H-chol, and AHR depletion significantly inhibited SACG. We also discovered a critical effect of ERK5 S496 phosphorylation on SUMOylation at a novel site of NRF2 (i.e., K518), which inhibited NRF2 transcriptional activity without affecting ERK5 kinase activity and antagonized oxidized LDL (oxLDL)-induced SASP. Specific ERK5 kinase inhibitors (AX15836 and XMD8-92) inhibited oxLDL-induced ERK5 S496 phosphorylation, suggesting that ERK5 S496 phosphorylation was involved at least in part of the effects of these inhibitors. We have discovered a novel mechanism in which ERK5 S496 phosphorylation directly inhibits NRF2 activity by upregulating NRF2 K518 SUMOylation and AHR induction, subsequently inducing SACG and AthS.
Abstract 12996: Outcomes of Cardiac Resynchronization Therapy in Transthyretin Wild-Type Cardiac Amyloidosis
Introduction: Cardiac resynchronization therapy (CRT) has known benefit for heart failure (HF) with reduced left ventricular ejection fraction (LVEF) and dyssynchrony. However, very little is known about its benefit in infiltrative cardiomyopathies such as cardiac amyloidosis (CA) due to relative rarity of these conditions. Methods: This retrospective case series (2003-2021) comprised patients with HF due to transthyretin wild-type CA with (case) or without (control) CRT implant. Only controls with an indication for CRT or LVEF <40% were included. To further match disease severity, cases were 1:1 matched (propensity score tolerance 0.04) to controls for age, NYHA class, and CA stage (UK Staging). Primary outcome was MACE (major adverse cardiac events) which included stroke, myocardial infarction, HF hospitalization and cardiac mortality during a 3-year follow-up. Loss to follow-up was censored as per last visit date. LVEF and NYHA were noted closest to 1-year follow-up. Survival analysis for MACE was performed with Kaplan-Meier (KM) and multivariable cox regression models. Results: Study Cohort (n=160) had a mean age of 75.5 (SD 7.8) years and 97.5% were males. A majority had NYHA class 2 or 3 (92.3%) and CA stage 2 (42.2.%). Notably, median LVEF at baseline was lower in controls (33.5 vs 36.5; P = .001) and 77.5% of controls had an indication for CRT device. A total of 79 MACE events occurred, most frequent being HF hospitalization (n=45). KM curves were comparable for MACE events in the two groups (log-rank test; P = .059). Even after adjusting, as in table, CRT device was not associated with MACE events (adjusted HR 0.66; 95% CI 0.40-1.09; P = .106). Lastly, change in LVEF ( P = .84) and NYHA ( P = .86) at follow-up was similar in cases vs controls. Conclusions: The findings of this largest yet observational study to examine this question suggest that CRT in patients with transthyretin wild-type CA does not favorably impact outcomes for MACE events, improve LVEF or NYHA functional class.
Abstract 12057: Absence of Pericarditis Recurrence in Rilonacept-Treated Patients With COVID-19 and mRNA Vaccinations: Experience From Phase 3 Rhapsody Long-Term Extension
Introduction: Rare cardiac complications of COVID-19 and COVID-19 mRNA vaccination include pericarditis and myocarditis. Patients with recurrent pericarditis may be at increased risk of triggered recurrence. The known efficacy of the interleukin (IL)-1 antagonist rilonacept in treating and preventing recurrence could inform COVID-19 disease and vaccination management. Methods: The Phase 3 trial RHAPSODY was a global, double-blind, placebo-controlled, randomized-withdrawal study. A long-term extension (LTE) enabled up to 24 months further open-label treatment from May 2020 until June 2022. Concomitant vaccination data and adverse events, including COVID-19, were collected. Results: No COVID-19 cases were reported during the run-in and randomized withdrawal periods (n=86). As of the 6 May 2022 data cutoff, a COVID-19 AE was reported in 19% (14/74) of LTE subjects, of whom 12 were on rilonacept: 5 of 44 fully-vaccinated (≥14 days beyond second serial dose) subjects (11.4%) and 9 of 30 unvaccinated or partially-vaccinated subjects (30.0%). Of the fully-vaccinated subjects, 1 case occurred ~11 months post primary vaccination cycle (no booster). COVID-19 severity was mild (n= 11), moderate (n=2), or severe (n=1). All cases resolved except the severe AE complicated by comorbidities; the subject discontinued. Of 12 subjects receiving rilonacept at the time of COVID-19 diagnosis, 10 maintained dosing with rilonacept, 1 interrupted rilonacept for ~4 weeks, and 1 discontinued rilonacept permanently; none experienced a pericarditis recurrence (PR) after the AE. The remaining 2 subjects had previously interrupted rilonacept for off-treatment observation: one had a PR >4.5 months after suspending rilonacept and 18 days after COVID-19 resolution; no PR in the other (>6 months). There were no PR AEs associated with COVID-19 vaccination (all subjects were receiving rilonacept). Conclusions: In patients on rilonacept in this study, although numbers are small, vaccination reduced COVID-19 events, pericarditis recurrence was not increased by vaccination or disease, and no pericarditis recurrences occurred during rilonacept treatment. One pericarditis recurrence occurred remotely after rilonacept suspension in the peri-COVID-19 period.
Abstract 11653: Prolonged Rilonacept Treatment in Rhapsody Long-Term Extension Provided Persistent Reduction of Pericarditis Recurrence Risk
Introduction: Rilonacept reduced pericarditis recurrence in the phase 3 trial RHAPSODY. The long-term extension (LTE) enabled further insights into efficacy, safety, and clinical decision making. Methods: The RHAPSODY run-in (RI) and randomized-withdrawal periods were followed by an LTE that enabled open-label rilonacept treatment up to 24 additional months. A decision at 18 months after the most recent recurrence was based on clinical status at investigator discretion: 1) continue rilonacept on-study, 2) suspend rilonacept for observation or 3) discontinue from the LTE without observation. Endpoints included recurrence and quality of life. Results: In May 2020, 74 of 75 eligible subjects continued to LTE; US subjects (n=45) switched to commercial therapy or discontinued in April 2021 (treatment duration from RI baseline [median; maximum] 18; 27 months). Non-US subjects (n=29) completed the LTE in June 2022 (treatment duration from RI baseline [median; maximum] 27; 33 months). Concomitant oral medications during LTE: 22% NSAIDS, 20% colchicine, 0% corticosteroids, 43% none. Inflammation signs (CRP), RP symptoms (PGIPS), and recurrences were low on-treatment. Before the 18-month decision (n=74), there were 3 investigator-assessed recurrences (0.04 per patient-year). At the 18-month decision (n=52), 64% (n=33) continued rilonacept on-study, 15% (n=8) suspended rilonacept for observation, and 21% (n=11) discontinued the study without observation, of whom 7 switched to commercial rilonacept. There was a 75% recurrence rate (n=6/8) in the off-treatment observation group (median time to event 11.8 [3.7, Not-Estimable (NE)] weeks) but only 1 recurrence in subjects on rilonacept (time to event NE [too few events]) associated with a 4-week interruption; HR 0.018, p<0.0001; Fig 1. Conclusions: Continued rilonacept treatment resulted in continued treatment response, whereas treatment suspension at 18 months may be associated with pericarditis recurrence.
Mechanism of Action of KL-50, a Novel Imidazotetrazine for the Treatment of Drug-Resistant Brain Cancers
Glioblastoma (GBM) is a lethal brain cancer with a five-year survival rate of <5%. Approximately half of GBM tumors lack the DNA repair protein O6-methylguanine DNA methyltransferase (MGMT), which reverses O6-alkylguanine (O6G) lesions. Patients presenting MGMT– GBM are treated with surgery followed by radiation therapy and temozolomide (TMZ), an imidazotetrazine prodrug that produces O6-methylguanine (O6MeG) lesions. However, ~50% of these patients will develop TMZ resistance by silencing of the DNA mismatch repair (MMR) pathway. We recently reported that the novel N3-(2-fluoroethyl)imidazotetrazine “KL-50” is efficacious and well-tolerated in murine models of TMZ-resistant GBM (Lin et al. Science 2022, 377, 502). Herein, we rigorously establish that KL-50 generates DNA interstrand crosslinks (ICLs) by DNA alkylation to generate O6-(2-fluoroethyl)guanine (O6FEtG), displacement of fluoride to form an N1,O6-ethanoguanine (N1,O6EtG) intermediate, and ring-opening by the adjacent cytidine. 2-Chloroethylating agents, such as lomustine and mitozolomide (MTZ), generate the same ICL by an analogous mechanism. However, DNA ICLs form >10-fold more slowly from O6FEtG than O6ClEtG, and this slower rate of cross-linking allows MGMT to reverse the initial O6FEtG in healthy tissue while also reducing MGMT–DNA cross-links arising from addition of MGMT to the N1,O6EtG intermediate. KL- 50 is efficacious in an intracranial patient-derived murine xenograft of TMZ-resistant, MGMT–/MMR– GBM (mOS = 205, 28, and 26 d for KL-50, TMZ, and vehicle-treated control, respectively) and in murine models of newly-diagnosed MGMT–/MMR+ GBM, suggesting its use in recurrent and up-front settings, respectively. These studies underscore the significance of considering the rates of chemical DNA modification and biochemical DNA repair in the design of systemic DNA alkylation agents.
ATRT-15. ATRTS HIJACK EPIGENETIC MECHANISMS TO PROMOTE IMMUNOSUPPRESSION AND ESCAPE FROM NK CELL THERAPY
Abstract Atypical Teratoid/Rhabdoid Tumors (ATRTs) are malignant tumors of the central nervous system in children. They are almost universally characterized by genetic loss of SWI/SNF Related, Matrix Associated, Actin Dependent Regulator of Chromatin Subfamily member B1 (SMARCB1) - a core subunit of the ATP-dependent SWI/SNF chromatin remodeling complex, and dysregulation of lineage restricted enhancers. Here, we show that tumor subgroup-specific upregulation of a distant member of the transforming growth factor-β (TGF-β), bone morphogenic factor (BMF) family of proteins drives insensitivity to NK-mediated cytolysis in vitro and in vivo. Mechanistically, subgroup-specific loss of chromatin occupancy by the RE1 Silencing Transcription Factor (REST) to its consensus RE1 motif, allowed deposition of enhancer-specific histone H3 lysine4 (K4) mono-methylation and histone H3K27 acetylation marks to activate an enhancer-promoter interaction. Restoration of REST binding or BET-domain inhibition resulted in a significant reduction in the enhancer marks and enhancer-promoter interaction and involved histone H3K27me3 deposition at the REST binding site, to facilitate gene silencing and sensitization of ATRTs to NK-mediated cytolysis. Thus, our study has identified a novel function for REST as a modulator of tumor-intrinsic enhancer activity and tumor-extrinsic immune microenvironment. Of equal significance, we highlight a role of REST in recruiting the polycomb repressive complex-2 (PRC2) in gene silencing in ATRTs.