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Medulloblastoma is the most common malignant brain tumor in children. It has WNT-driven, SHH-driven/TP53 mutant, SHH-driven/TP53 wildtype, and non-WNT/non-SHH subgroups. MAGMAS (Mitochondrial Associated Granulocyte Macrophage colony-stimulating factor Signaling molecules) encodes a mitochondrial import inner membrane translocase subunit and is responsible for the translocation of matrix proteins across the inner membrane. We previously reported that a small molecule MAGMAS inhibitor, BT9, decreases cell proliferation, migration, and oxidative phosphorylation in adult glioblastoma cell lines. The aim of our study was to investigate whether the chemotherapeutic effect of BT9 can be extended to pediatric medulloblastoma.MethodsDAOY (SHH driven/tp53 mutant) and D425 (non-SHH group 3) were treated with BT9. For in vitro analysis, cell proliferation, death, migration, invasion, and metabolic activity were assessed using MTT assay, TUNEL staining, scratch wound assay, Matrigel invasion chambers, and seahorse assay, respectively. A D425 orthotopic xenograft mouse model was used to evaluate BT9 efficacy in vivo.ResultsBT9 treatment resulted in a significant decrease in cell proliferation (DAOY, 24 hours IC50: 3.6 μM, 48 hours IC50: 2.3 μM, 72 hours IC50: 2.1 μM; D425 24 hours IC50: 3.4 μM, 48 hours IC50: 2.2 μM, 72 hours IC50: 2.1 μM) and a significant increase in cell death (DAOY, 24 hours p = 0.0004, 48 hours p

Ubiquitin proteasome-mediated protein degradation has been implicated in posttranslational oncogenesis in medulloblastoma. Current research is evaluating the clinical implications of proteasome inhibition as a therapeutic target. In medulloblastoma cell lines, proteasome inhibitors induce apoptosis and inhibit cell proliferation via multiple pathways involving activation of caspase pathways, NFκB (nuclear factor kappa-light-chain-enhancer of activated B cells) pathway inhibition, reduced AKT/mTOR pathway activity, and pro-apoptotic protein expression. Second-generation proteasome inhibitors demonstrate blood-brain barrier penetration while maintaining antitumor effect. This review summarizes the ubiquitin-proteasome system in the pathogenesis of medulloblastoma and the potential clinical implications.

Background: The gift of postmortem tissue donation is critical to pediatric central nervous system (CNS) research. As a "Center of Excellence" for the Gift from a Child Program, our institution has a well-established postmortem tissue donation program. Our objective was to determine if differences exist between patients who participated in and those that declined research-based autopsy., Procedure: We performed a single-institution retrospective chart review of pediatric patients with CNS malignancies who died from their disease between January 1, 2021 and December 31, 2022. Individual clinical, demographic, and socioeconomic data were assessed. Population-level data were estimated using Zip Code Tabulation Areas. Descriptive statistics were used to compare categorical data., Results: Among the 23 patient families approached during the study time frame, 8/23 (35%) consented to participation. In the consented (C) versus declined (D) group, there was a higher percentage of White, non-Hispanic/Latino patients by self-reported race (C: 88% vs. D: 55%), and no patients who identified as Asian or Hispanic/Latino (C: 0% and 0% vs. D: 13% and 27%). Of all patients approached, two required interpreters (9%), and both families declined participation. The rate of private insurance was higher in the consented group (C: 75% vs. D: 47%) compared to Medicaid as primary insurance in the declined group (C: 13% vs. D: 53%).  CONCLUSIONS: Future research should aim to understand and improve identified disparities to ensure research advancements benefit all children with CNS malignancies. One area we plan to address is improved communication with non-English-speaking families by partnering with our interpreter services., (© 2024 Wiley Periodicals LLC.)

Objective: The aim of this study was to summarize the prognosis of recurrent infratentorial ependymomas based on treatment and molecular characterization., Methods: Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, the authors searched the PubMed, Scopus, Embase, and Ovid databases for studies on recurrent infratentorial ependymomas in patients younger than 25 years of age. Exclusion criteria included case series of fewer than 5 patients and studies that did not provide time-dependent survival data., Results: The authors' database search yielded 482 unique articles, of which 18 were included in the final analysis. There were 479 recurrent infratentorial pediatric ependymomas reported; 53.4% were WHO grade II and 46.6% were WHO grade III tumors. The overall mortality for recurrent infratentorial pediatric ependymomas was 49.1% (226/460). The pooled mean survival was 30.2 months after recurrence (95% CI 22.4-38.0 months). Gross-total resection (GTR) was achieved in 243 (59.0%) patients at initial presentation. The mean survival postrecurrence for those who received initial GTR was 42.3 months (95% CI 35.7-47.6 months) versus 26.0 months (95% CI 9.6-44.6 months) for those who received subtotal resection (STR) (p = 0.032). There was no difference in the mean survival between patients who received GTR (49.3 months, 95% CI 32.3-66.3 months) versus those who received STR (41.4 months, 95% CI 11.6-71.2 months) for their recurrent tumor (p = 0.610). In the studies that included molecular classification data, there were 169 (83.3%) posterior fossa group A (PFA) tumors and 34 (16.7%) posterior fossa group B (PFB) tumors, with 28 tumors harboring a 1q gain. PFA tumors demonstrated worse mean postprogression patient survival (24.7 months, 95% CI 15.3-34.0 months) compared with PFB tumors (48.0 months, 95% CI 32.8-63.2 months) (p = 0.0073). The average postrecurrence survival for patients with 1q+ tumors was 14.7 months., Conclusions: The overall mortality rate for recurrent infratentorial ependymomas was found to be 49.1%, with a pooled mean survival of 30.2 months in the included sample population. More than 80% of recurrent infratentorial ependymomas were of the PFA molecular subtype, and both PFA tumors and those with 1q gain demonstrated worse prognosis after recurrence.