Citations

Abstract Neurofibromatosis type 1 (NF1) syndrome is an autosomal dominant cancer predisposition syndrome defined by germline deletion of one NF1 allele. Somatic loss of heterozygosity in the remaining NF1 allele in Schwann lineage cells gives rise to benign tumors known as plexiform neurofibromas. These tumors have a high risk of transforming into malignant peripheral nerve sheath tumors (MPNST) through the sequential deletion of CDKN2A/B followed by recurrent mutations in SUZ12 or EED, constituting the inactivation of polycomb repressor complex 2 (PRC2). PRC2 is a transcriptional repressor complex involved in the silencing of several development and differentiation genes. Loss of this complex leads to a depletion in trimethylation marks on Histone H3 Lysine 27 (H3K27me3) and the subsequent gain of acetylation marks on the same lysine residue (H3K27Ac). These molecular hallmarks are shared with diffuse intrinsic pontine gliomas (DIPG) harboring the H3K27M mutation which prevents effective deposition of H3K27me3, thus having similar molecular phenotypes to MPNST. However, the full range of epigenetic consequences of these events are currently not well characterized. Additionally, given that MPNSTs originate from cells of neural crest origin and DIPGs from cells of neural origin, it is not know to what degree epigenetic changes stemming from H3K27me3-loss are general across tumors or are context-dependent based on cell-of-origin. In order to contribute to this effort, the Largaespada lab has engineered Schwann cell lines to harbor deletions in NF1 and either SUZ12 or EED and assayed the H3K27ac landscape of these cells in addition to patient-derived MPNST cell lines. Utilizing the ranked ordering of super enhancers (ROSE) algorithm, we have identified common super enhancers within each MPNST cell line. These super enhancer elements are located nearby a variety of putative oncogenes responsible for the maintenance of cell identity. These elements were then compared to publicly available data from DIPG primary and patient-derived samples to understand common regulatory events driven by loss of H3K27me3 as well as molecular signatures present only in MPNST or in DIPG that may be a result of PRC2 or H3K27M alone. We further characterized these super enhancers by assessing the expression levels of their associated genes to understand their role in transcriptional activation. These efforts provide a roadmap of the super enhancer landscape of both MPNSTs and DIPGs to investigate novel mechanisms of H3K27me3-dependent tumorigenesis while also contributing to knowledge of potential effects of H3K27me3-loss that dependent on the cell-of-origin for each respective tumor. Citation Format: Christopher M. Stehn, Minu Bhunia, Kyle Williams, Alex T. Larsson, Ariel Caride, Jeong-Heon Lee, Tamas Ordog, David Largaespada. Characterizing the super enhancer landscape of H3K27me3 loss in MPNST and DIPG [abstract]. In: Proceedings of the AACR Special Conference on Brain Cancer; 2023 Oct 19-22; Minneapolis, Minnesota. Philadelphia (PA): AACR; Cancer Res 2024;84(5 Suppl_1):Abstract nr B009.

Multi-agent regimens incorporating immunomodulatory (IMiD®) agents such as thalidomide, lenalidomide, and pomalidomide have become the preferred standard of care for the treatment of patients with multiple myeloma (MM), resulting in improved survival outcomes. Currently, there are three IMiD agents approved for the treatment of MM: thalidomide, lenalidomide, and pomalidomide. Lenalidomide is commonly used to treat patients with newly diagnosed MM and as maintenance therapy following stem cell transplant or after disease relapse. Pomalidomide, the focus of this review, is approved in patients with relapsed/refractory MM (RRMM). Despite survival benefits, IMiD agents each have different safety profiles requiring consideration both prior to starting therapy and during treatment. Adverse event (AE) management is essential, not only to ensure treatment adherence and thus ensure optimal efficacy but also to maintain patient quality of life. Here, we discuss AEs associated with pomalidomide and present five clinically relevant hypothetical case studies in patients with RRMM to provide scenario-driven guidance regarding treatment selection and AE prevention and management in the clinical setting. Lastly, as new treatment approaches continue to be explored in MM, we also discuss novel cereblon E3 ligase modulator (CELMoD™) agents including iberdomide (CC-220) and mezigdomide (CC-92480).

Background Higher scores for the American Heart Association Life's Essential 8 (LE8) metrics, blood pressure, cholesterol, glucose, body mass index, physical activity, smoking, sleep, and diet, are associated with lower risk of chronic disease. Socioeconomic status (SES; employment, insurance, education, and income) is associated with LE8 scores, but there is limited understanding of potential differences by sex. This analysis quantifies the association of SES with LE8 for each sex, within Hispanic Americans, non‐Hispanic Asian Americans, non‐Hispanic Black Americans, and non‐Hispanic White Americans. Methods and Results Using cross‐sectional data from the National Health and Nutrition Examination Survey, years 2011 to 2018, LE8 scores were calculated (range, 0–100). Age‐adjusted linear regression quantified the association of SES with LE8 score. The interaction of sex with SES in the association with LE8 score was assessed in each racial and ethnic group. The US population representatively weighted sample (13 529 observations) was aged ≥20 years (median, 48 years). The association of education and income with LE8 scores was higher in women compared with men for non‐Hispanic Black Americans and non‐Hispanic White Americans ( P for all interactions <0.05). Among non‐Hispanic Asian Americans and Hispanic Americans, the association of SES with LE8 was not different between men and women, and women had greater LE8 scores than men at all SES levels (eg, high school or less, some college, and college degree or more). Conclusions The factors that explain the sex differences among non‐Hispanic Black Americans and non‐Hispanic White Americans, but not non‐Hispanic Asian Americans and Hispanic Americans, are critical areas for further research to advance cardiovascular health equity.

Intrathecal synthesis of central nervous system (CNS)-reactive autoantibodies is observed across patients with autoimmune encephalitis (AE), who show multiple residual neurobehavioral deficits and relapses despite immunotherapies. We leveraged two common forms of AE, mediated by leucine-rich glioma inactivated-1 (LGI1) and contactin-associated protein-like 2 (CASPR2) antibodies, as human models to comprehensively reconstruct and profile cerebrospinal fluid (CSF) B cell receptor (BCR) characteristics. We hypothesized that the resultant observations would both inform the observed therapeutic gap and determine the contribution of intrathecal maturation to pathogenic B cell lineages. From the CSF of three patients, 381 cognate-paired IgG BCRs were isolated by cell sorting and scRNA-seq, and 166 expressed as monoclonal antibodies (mAbs). Sixty-two percent of mAbs from singleton BCRs reacted with either LGI1 or CASPR2 and, strikingly, this rose to 100% of cells in clonal groups with ≥4 members. These autoantigen-reactivities were more concentrated within antibody-secreting cells (ASCs) versus B cells ( P < 0.0001), and both these cell types were more differentiated than LGI1- and CASPR2-unreactive counterparts. Despite greater differentiation, autoantigen-reactive cells had acquired few mutations intrathecally and showed minimal variation in autoantigen affinities within clonal expansions. Also, limited CSF T cell receptor clonality was observed. In contrast, a comparison of germline-encoded BCRs versus the founder intrathecal clone revealed marked gains in both affinity and mutational distances ( P = 0.004 and P < 0.0001, respectively). Taken together, in patients with LGI1 and CASPR2 antibody encephalitis, our results identify CSF as a compartment with a remarkably high frequency of clonally expanded autoantigen-reactive ASCs whose BCR maturity appears dominantly acquired outside the CNS.

Background and Objectives: It is unclear whether induced hypertension in acute ischemic stroke (AIS) may improve long-term outcomes. We conducted a systematic review and meta-analysis to compare the safety and efficacy of induced hypertension vs standard medical care in patients presenting with acute ischemic stroke within 72 hours of symptom onset. Methods: Two reviewers systematically searched PubMed using the prespecified terms “induced hypertension” or “blood pressure augmentation” plus “ischemic stroke” for clinical trials that reported functional independence (mRS 0-2) at 90 days. The safety outcome was symptomatic intracranial hemorrhage (sICH). Pooled odds ratio (OR) and 95% CI across trials were synthesized using fixed-effect model based on Mantel-Haenszel methods. Forest plots were constructed. Results: Three clinical trials with 270 AIS patients treated with induced hypertension (n=126) or standard medical care (n= 144) were included. Mean age was 66.6 years, 35.2% were women, and the mean initial NIHSS was 7.5. The rate of functional independence at 90 days was higher in patients treated with induced hypertension (70.6%) versus control (54.9%) (OR 1.88; 95% CI 1.13-3.11; p=0.01). sICH did not differ between patients treated with induced hypertension (<1%) versus control (<1%) (OR 1.03; 95% CI 0.14-7.45; p=0.98). Discussion: Among patients presenting with acute ischemic stroke with 72 hours of symptoms onset, induced hypertension resulted in better functional outcome at 90 days than standard medical care and did not increase risk of sICH. Large RCTs to test this observation are ongoing and needed to guide clinical practice.

Staphylococcus aureus skin colonization and eosinophil infiltration are associated with many inflammatory skin disorders, including atopic dermatitis, bullous pemphigoid, Netherton’s syndrome, and prurigo nodularis. However, whether there is a relationship between S. aureus and eosinophils and how this interaction influences skin inflammation is largely undefined. We show in a preclinical mouse model that S. aureus epicutaneous exposure induced eosinophil-recruiting chemokines and eosinophil infiltration into the skin. Remarkably, we found that eosinophils had a comparable contribution to the skin inflammation as T cells, in a manner dependent on eosinophil-derived IL-17A and IL-17F production. Importantly, IL-36R signaling induced CCL7-mediated eosinophil recruitment to the inflamed skin. Last, S. aureus proteases induced IL-36α expression in keratinocytes, which promoted infiltration of IL-17-producing eosinophils. Collectively, we uncovered a mechanism for S. aureus proteases to trigger eosinophil-mediated skin inflammation, which has implications in the pathogenesis of inflammatory skin diseases.

572 Background: Bladder preservation with trimodal therapy (TMT), which consists of maximal transurethral resection of bladder tumors followed by chemoradiation, is now included in guidelines with radical cystectomy (RC) as options for definitive management of muscle-invasive bladder cancer (MIBC). Prospective randomized controlled trial data to help guide treatment selection are lacking, and prior efforts to bridge this knowledge gap have failed primarily due to poor accrual. A recent retrospective analysis comparing TMT to RC reported similar oncologic outcomes between these treatments when performed in highly selected patients. However, treatment toxicities and costs vary significantly between these management options. To investigate the impact of these outcomes on relative treatment value, we evaluated the comparative cost-effectiveness of TMT and RC for treatment of MIBC. Methods: Cost-effectiveness was compared between TMT and RC for patients with a solitary, muscle-invasive tumor less than 7cm, no or unilateral hydronephrosis, limited carcinoma in situ, and adequate bladder function (criteria utilized in a recent retrospective comparative series) using a microsimulation model with a 5-year horizon from a Medicare payer perspective. Additionally, a 10-year lifetime horizon was evaluated to better understand the impact of long-term outcome uncertainty on cost-effectiveness. Based on recently published multicenter retrospective propensity score matched data, metastatic progression and survival probabilities were assumed to be equivalent between treatments. Utility values and additional probabilities, including both short and long-term treatment toxicities, were obtained from published literature. Primary outcomes of interest included effectiveness measured in quality adjusted life years (QALYs) and incremental cost-effectiveness ratios (ICER) using a willingness-to-pay threshold of $100,000/QALY. One-way and probabilistic sensitivity analyses were performed to assess the robustness of the model. Results: At 5 years, the average cost was $32,286.35 higher for TMT versus RC. The average QALYs were 3.88 and 3.96 for RC and TMT respectively. TMT was not cost-effective at 5-year (ICER: $379,917.21/QALY) or 10-year (ICER: $222,704.78/QALY) time horizons. On one-way sensitivity analyses, TMT would become cost effective if: 1) TMT costs were less than $16,152; or 2) TMT resulted in a 13.3% improvement in metastasis free survival relative to RC. Conclusions: Although it resulted in similar quality and duration of life, TMT was not cost-effective relative to RC at 5 and 10 years given higher treatment costs. These findings support the role of both TMT and RC in management of MIBC and highlight the need for continued efforts to reduce healthcare costs associated with TMT.

Abstract Background Recent evidence challenges the current standard of offering surgery to patients with ileocecal Crohn’s disease only when they present complications of the disease. Methods A retrospective, multicenter comparative analysis was performed including patients operated for primary ileocecal CD at 12 referral centers. Patients were divided in 2 groups, according to indication of surgery for inflammatory (ICD) or complicated (CCD) phenotype. Short-term results were compared. Patients operated on for primary isolated ileocaecal CD (last 50 cm of the terminal ileum and cecum), either for predominantly inflammatory phenotype or for complications of the disease (stricturing or fistulizing pattern), between January 2012 - December 2021 were considered eligible to participate in this study. Patients with previous abdominal procedures for CD, and patients who had activity of the disease in other intestinal segments other than the ileocaecal region at the time of surgery, were excluded from the study. Results 2013 patients were included, 291 (14.5%) in the ICD group. No differences were found between groups in time from diagnosis to surgery or in the levels of exposure to biologic drugs before indication of surgery. CCD patients had higher rates of low BMI, anemia (40.9 vs. 27%, p: &lt; 0.001), and low albumin (11.3 vs. 2.6%, p: &lt; 0.001). CCD patients had longer operations, lower rates of laparoscopic approach (84.3 vs. 93.1%, p: 0.001), and higher conversion rates (9.3 vs. 1.9%, p: &lt; 0.001). CCD had longer hospital stay and higher postoperative complication rates (26.1 vs. 21.3%, p: 0.083). Anastomotic leakage and reoperations were also more frequent in this group. More patients in the CCD group required an extended bowel resection (14.1 vs. 8.3%, p: 0.017). In multivariate analysis, CCD was associated with prolonged surgeries (OR: 3.44, p: 0.001) and requirements of multiple intraoperative procedures (OR: 8.39, p: 0.030). Conclusion Indication of surgery in patients who present an inflammatory phenotype of CD was associated with better outcomes when compared to patients operated on for complications of the disease, without a difference between groups in time from diagnosis to surgery.

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical trial updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported. In 2003, the Eastern Cooperative Oncology Group initiated a randomized phase III clinical trial (E4402) comparing two different rituximab dosing strategies for patients with previously untreated low–tumor burden follicular lymphoma. Rituximab-responsive patients (n = 299) were randomly assigned to either a retreatment rituximab (RR) strategy or a maintenance rituximab (MR) strategy. Each dosing strategy was continued until treatment failure. The primary end point of the study was time to treatment failure (TTF). In the original report, there was no difference in TTF between the two dosing strategies. Here, we report on the long-term outcomes for secondary end points of time to first cytotoxic therapy, duration of response, and overall survival (OS). At 7 years, 83% of MR patients had not required first chemotherapy compared with 63% of RR patients (hazard ratio, 2.37 [95% CI, 1.5 to 3.76]). At 7 years, 71% of MR remained in their first remission compared with 37% of RR patients. Despite the improved first remission length with MR, there was no difference in OS at 10 years (83% v 84%). With mature long-term data, we confirm that prolonged maintenance rituximab does not confer an OS advantage in low–tumor burden follicular lymphoma.