Neuroblastoma, Version 2.2024, NCCN Clinical Practice Guidelines in Oncology.

Neuroblastoma is the most common extracranial solid tumor diagnosed in children. This inaugural version of the NCCN Guidelines for Neuroblastoma provides recommendations for the diagnosis, risk classification, and treatment of neuroblastoma. The information in these guidelines was developed by the NCCN Neuroblastoma Panel, a multidisciplinary group of representatives with expertise in neuroblastoma, consisting of pediatric oncologists, radiologists, pathologists, surgeons, and radiation oncologists from NCCN Member Institutions. The evidence-based and consensus recommendations contained in the NCCN Guidelines are intended to guide clinicians in selecting the most appropriate treatments for their patients with this clinically heterogeneous disease.

Acute lipopolysaccharide (LPS)-induced cell membrane hyperpolarization is independent of voltage gated and calcium activated potassium channels.

The gram-negative toxin lipopolysaccharides (LPS) are known to trigger inflammatory cytokines in mammals, which can result in pathological responses. Upon treatment of bacterial sepsis with antibiotics, the lysing bacteria can present a surge in LPS, inducing a cytokine storm. However, LPS can also have direct cellular effects, including transient rapid hyperpolarizing of the membrane potential, blocking glutamate receptors and even promoting release of glutamate. The detailed mechanism of action for these immediate responses is still unresolved. In addressing the membrane hyperpolarization, voltage gated K+ channel blockers 4-aminopyridine (4-AP, 3 mM), quinidine hydrochloride monohydrate (0.1 mM) and tetraethylammonium (TEA, 20 mM) were examined along with RNAi knockdowns of potential calcium activated K+ channels. The immediate responses of LPS were not blocked. Even in the presence of glutamate, the membrane still hyperpolarizes with LPS. When the driving gradient for the ionotropic glutamate receptors is enhanced during hyperpolarization, spontaneous quantal responses are dampened in amplitude. Thus, glutamate receptors are blocked, and the mechanism of hyperpolarization remains unresolved. The larval Drosophila glutamatergic neuromuscular junction is used as a model synaptic preparation to address the direct rapid actions by LPS.

Clinical characteristics and outcomes of adult alveolar rhabdomyosarcoma patients on first-line systemic therapies: A single-institution cohort.

Background: Rhabdomyosarcomas are the most common soft tissue sarcoma in children, and pediatric alveolar rhabdomyosarcoma (ARMS) prognosis has improved based on cooperative studies. However, in adults, ARMS is significantly rarer, has poorer outcomes, and currently lacks optimal treatment strategies. Objective: This study aimed to evaluate the clinical outcome of an adult ARMS population with different front-line systemic chemotherapies and determine if any chemotherapy regimen is associated with improved survival. Materials and methods: This is a retrospective study of histologically confirmed fusion-positive ARMS patients over 18 years of age, who were treated at MD Anderson Cancer Center (MDACC) from 2004 to 2021 and received systemic chemotherapy. Descriptive clinical statistics were performed, including staging, front-line chemotherapy, multimodal therapy usage, response rates, and survival analyses. Results: 49 ARMS patients who received upfront chemotherapy were identified. Locoregional treatments included radiotherapy (RT) alone (29%, n = 14), surgery alone (10%, n = 5), or both (45%, n = 22). Median overall survival (OS) for the entire cohort was 3.6 years, and the overall response rate to systemic therapy was 89%. No chemotherapy regimen showed OS benefit, specifically analyzing the pediatric-based vincristine, actinomycin-D, cyclophosphamide (VAC) or adult-based vincristine, doxorubicin, ifosfamide (VDI) regimens, even when controlled for other clinical risk factors. Conclusion: In this single-center contemporary series, adult ARMS patient outcomes remain poor. There was no statistically significant OS difference in patients who did or did not receive adult or pediatric based ARMS regimens, although a high overall response rate to chemotherapy was seen across the entire cohort. Based on these observations, further randomized prospective studies are necessary to delineate which frontline chemotherapy regimen is most beneficial in this rare adult cancer.

Deciphering cellular heterogeneity in Spodoptera frugiperda midgut cell line through single cell RNA sequencing.

Using the 10x Genomics Chromium single-cell RNA sequencing (scRNA-seq) platform, we discovered unexpected heterogeneity in an established cell line developed from the midgut of the Fall armyworm, Spodoptera frugiperda, a major global pest. We analyzed the sequences of 18,794 cells and identified ten unique cellular clusters, including stem cells, enteroblasts, enterocytes and enteroendocrine cells, characterized by the expression of specific marker genes. Additionally, these studies addressed an important knowledge gap by investigating the expression of genes coding for respiratory and midgut membrane insecticide targets classified by the Insecticide Resistance Action Committee. Dual-fluorescence tagging method, fluorescence microscopy and fluorescence-activated cell sorting confirmed the expression of midgut cell type-specific genes. Stem cells were isolated from the heterogeneous population of SfMG-0617 cells. Our results, validated by KEGG and Gene Ontology analyses and supported by Monocle 3.0, advance the fields of midgut cellular biology and establish standards for scRNA-seq studies in non-model organisms.

Addition of temsirolimus to chemotherapy in children, adolescents, and young adults with intermediate-risk rhabdomyosarcoma (ARST1431): a randomised, open-label, phase 3 trial from the Children's Oncology Group.

BACKGROUND: The Children's Oncology Group defines intermediate-risk rhabdomyosarcoma as unresected FOXO1 fusion-negative disease arising at an unfavourable site or non-metastatic FOXO1 fusion-positive disease. Temsirolimus in combination with chemotherapy has shown promising activity in patients with relapsed or refractory rhabdomyosarcoma. We aimed to compare event-free survival in patients with intermediate-risk rhabdomyosarcoma treated with vincristine, actinomycin, and cyclophosphamide alternating with vincristine and irinotecan (VAC/VI) combined with temsirolimus followed by maintenance therapy versus VAC/VI alone with maintenance therapy. METHODS: ARST1431 was a randomised, open-label, phase 3 trial conducted across 210 institutions in Australia, Canada, New Zealand, and the USA. Eligible patients were those aged 40 years or younger with non-metastatic FOXO1-positive rhabdomyosarcoma or unresected FOXO1-negative rhabdomyosarcoma disease from unfavourable sites. Two other groups of patients were also eligible: those who had FOXO1-negative disease at a favourable site (excluding orbit) that was unresected; and those who were aged younger than 10 years with stage IV FOXO1-negative disease with distant metastases. Eligible patients had to have a Lansky performance status score of 50 or higher if 16 years or younger and a Karnofsky performance status score of 50 or higher if older than 16 years; all patients were previously untreated. Patients were randomised (1:1) in blocks of four and stratified by histology, stage, and group. Patients received intravenous VAC/VI chemotherapy with a cyclophosphamide dose of 1·2 g/m2 per dose per cycle with or without a reducing dose of intravenous weekly temsirolimus starting at 15 mg/m2 or 0·5 mg/kg per dose for those who weighed less than 10 kg. The total duration of therapy was 42 weeks followed by 6 months of maintenance therapy with oral cyclophosphamide plus intravenous vinorelbine for all patients. Temsirolimus was withheld during radiotherapy and for 2 weeks before any major surgical procedure. The primary endpoint was 3-year event-free survival. Data were analysed with a revised intention-to-treat approach. The study is registered with ClinicalTrials.gov (NCT02567435) and is complete. FINDINGS: Between May 23, 2016, and Jan 1, 2022, 325 patients were enrolled. In 297 evaluable patients (148 assigned to VAC/VI alone and 149 assigned to VAC/VI with temsirolimus), the median age was 6·3 years (IQR 3·0-11·3); 33 (11%) patients were aged 18 years or older; 179 (60%) of 297 were male. 113 (77%) of 148 patients were FOXO1 negative in the VAC/VI group, and 108 (73%) of 149 were FOXO1 negative in the VAC/VI with temsirolimus group. With a median follow-up of 3·6 years (IQR 2·8-4·5), 3-year event-free survival did not differ significantly between the two groups (64·8% [95% CI 55·5-74·1] in the VAC/VI group vs 66·8% [57·5-76·2] in the VAC/VI plus temsirolimus group (hazard ratio 0·86 [95% CI 0·58-1·26]; log-rank p=0·44). The most common grade 3-4 adverse events were anaemia (62 events in 60 [41%] of 148 patients in the VAC/VI group vs 89 events in 87 [58%] of 149 patients in the VAC/VI with temsirolimus group), lymphopenia (83 events in 65 [44%] vs 99 events in 71 [48%]), neutropenia (160 events in 99 [67%] vs 164 events in 105 [70%]), and leukopenia (121 events in 86 [58%] vs 132 events in 93 [62%]). There was one treatment-related death in the VAC/VI with temsirolimus group, categorised as not otherwise specified. INTERPRETATION: Addition of temsirolimus to VAC/VI did not improve event-free survival in patients with intermediate-risk rhabdomyosarcoma defined by their FOXO1 translocation status and clinical factors. Novel biology-based strategies are needed to improve outcomes in this population. FUNDING: The Children's Oncology Group (supported by the US National Cancer Institute, US National Institutes of Health).

The effects of doxapram and its potential interactions with K2P channels in experimental model preparations.

The channels commonly responsible for maintaining cell resting membrane potentials are referred to as K2P (two-P-domain K+ subunit) channels. These K+ ion channels generally remain open but can be modulated by their local environment. These channels are classified based on pharmacology, pH sensitivity, mechanical stretch, and ionic permeability. Little is known about the physiological nature of these K2P channels in invertebrates. Acidic conditions depolarize neurons and muscle fibers, which may be caused by K2P channels given that one subtype can be blocked by acidic conditions. Doxapram is used clinically as a respiratory aid known to block acid-sensitive K2P channels; thus, the effects of doxapram on the muscle fibers and synaptic transmission in larval Drosophila and crawfish were monitored. A dose-dependent response was observed via depolarization of the larval Drosophila muscle and an increase in evoked synaptic transmission, but doxapram blocked the production of action potentials in the crawfish motor neuron and had a minor effect on the resting membrane potential of the crawfish muscle. This indicates that the nerve and muscle tissues in larval Drosophila and crawfish likely express different K2P channel subtypes. Since these organisms serve as physiological models for neurobiology and physiology, it would be of interest to further investigate what types of K2P channel are expressed in these tissues. (212 words).

Event-free survival in relapsed and refractory rhabdomyosarcoma treated on cooperative group phase II trials: A report from the Children's Oncology Group.

BACKGROUND: Novel therapies are needed for relapsed and refractory rhabdomyosarcoma (RRMS). Phase II clinical trials in RRMS have typically utilized radiologic response as the primary activity endpoint, an approach that poses several limitations in RRMS. In this analysis, we aimed to estimate an event-free survival (EFS) endpoint for RRMS that could be used as a benchmark for future studies. PROCEDURE: We performed a retrospective study of patients with RRMS enrolling on 13 single-agent phase II Children's Oncology Group and legacy group trials from 1997 to 2016. All included trials used radiographic response as their primary activity endpoint. Six-month EFS was estimated from time of trial enrollment with 95% confidence intervals. Clinical characteristics, including trial of enrollment, sex, age, race, histology, number of prior chemotherapies, and radiographic response were evaluated for their impact on 6-month EFS. RESULTS: We identified 175 patients across 13 trials. The 6-month EFS was 16.8% (11.6%-22.8%). No differences were seen in 6-month EFS based on age, sex, race, or histology. There were nonsignificant trends toward improved 6-month EFS for patients with less than or equal to two prior lines of therapy versus higher than two, for patients enrolled on trials that achieved their primary radiographic response endpoint versus trials that did not, and for patients who achieved complete or partial response compared to those achieving stable disease. CONCLUSIONS: The prognosis of RRMS enrolled on single-agent phase II trials is poor. This pooled 6-month EFS of RRMS on single-agent trials may be used as a RRMS-specific benchmark for future single-agent phase II trials.

Adolescents and young adults with rhabdomyosarcoma: A report from the Soft Tissue Sarcoma Committee of the Children's Oncology Group.

INTRODUCTION: The impact of established prognostic factors on survival outcomes for childhood rhabdomyosarcoma (RMS) have not been well described in the adolescent and young adult (AYA) RMS patient population. METHODS: This is a retrospective analysis of patients with newly diagnosed RMS enrolled between 1997 and 2016 on seven previously reported Children's Oncology Group (COG) clinical trials. Demographics, clinical features, treatment details, and outcome data were collected. Five-year event-free survival (EFS) and overall survival (OS) were estimated for patients diagnosed at age 15-39 years and those diagnosed under age 15 years using the Kaplan-Meier method. Log-rank test was used to compare prognostic factors for EFS and OS. Factors significant in the univariable analysis were included in a Cox proportional hazards regression model. Nonsignificant covariates were removed from the multiple regression model. RESULTS: Total 2151 patients including 402 AYAs were analyzed. AYAs were more likely to present with primary tumors ≥5 cm in size, metastatic disease, alveolar histology, and have FOXO1 fusions compared to children. Five-year EFS for the AYA cohort was 44.2% versus 67% for children (p < .001), and 5-year OS was 52% for the AYA cohort versus 78% for children (p < .001). Multivariable analysis revealed tumor site, size and invasiveness, clinical group, and histology were prognostic in AYAs. CONCLUSION: AYAs with RMS have a poorer prognosis compared to younger children due to multiple factors. Further research focused on AYAs to better understand RMS biology and improve treatments is critical to improve survival.

Soft Tissue Sarcomas in Adolescents and Young Adults.

Soft tissue sarcomas (STS) represent a heterogeneous group of extraskeletal mesenchymal tumors that affect individuals throughout the entire age continuum. Despite this pervasive influence, key differences exist in the presentation of these sarcomas across varying age groups that have prevented a more uniform approach to management. Notably, rhabdomyosarcoma (RMS) is more common in children, while most nonrhabdomyosarcoma soft tissue sarcoma (NRSTS) subtypes are more prevalent in adults. Older patients with NRSTS appear to have more molecularly complex biology and often present with more advanced disease compared with children. Poorer outcome disparities are observed in older patients with RMS despite receiving similar treatment as younger patients. In this review, we highlight differences in epidemiology, biology, and management paradigms for pediatric and adult patients with STS and explore opportunities for a unified approach to enhance the care and outcomes within the AYA population.

In-person and virtual adaptation of an interprofessional palliative care communications skills training course for pediatric oncology clinicians.

Purpose: Effective, empathic communication is crucial for pediatric oncology clinicians when discussing palliative and end-of-life (PC/EOL) care with parents of children with cancer. Unfortunately, many parents report inadequate communication at these distressing times. This study evaluates the communication skills training (CST) clinicians received to deliver a PC/EOL communication intervention as part of a multi-site randomized-controlled trial (RCT). Methods: Clinicians from eight sites formed dyads (one physician and one nurse [RN] or advanced practice provider [APP]) and were trained over 3 days (in-person or virtually). Training was adapted from VitalTalk™ and included didactic instruction, videos, visual aids, and dedicated time to practice with simulated patients. Study participants completed a confidential, post-training online evaluation survey. A self-reported quality assurance checklist was used to measure fidelity to the communication protocol when delivered to parents during the RCT. Results: Thirty clinicians completed training; 26 completed post-training surveys including twelve (46.1%) physicians, 8 (30.8%) RNs and 6 (23.1%) APPs. Most were female (65.4%); white (80.8%), not Latinx (88.5%); 40-50 years old (53.9%); and in practice over 10 years (65.4%). Nine (34.6%) trained in-person; the rest trained virtually. Ninety-two percent reported the course was valuable or very valuable for developing their PC/EOL communication skills and 96% reported learning something new. Dyads trained virtually had similar fidelity to those trained in-person (95% and 90% respectively) when delivering the PC/EOL communication intervention to parents. Conclusion: This PC/EOL CST was valuable for improving pediatric oncology clinicians' communication skills, successfully implemented in-person and virtually, and translated effectively into practice.

Feasibility of combining temsirolimus to vincristine, dactinomycin, cyclophosphamide, and vincristine and irinotecan chemotherapy for children with intermediate-risk rhabdomyosarcoma: A report from Children's Oncology Group.

BACKGROUND: Temsirolimus has shown in vivo activity against rhabdomyosarcoma (RMS). We aimed to determine the feasibility of incorporating temsirolimus within the standard Children's Oncology Group (COG) chemotherapy backbone of vincristine, actinomycin-D, and cyclophosphamide (VAC) alternating with vincristine and irinotecan (VI) in children with intermediate-risk (IR) RMS. METHODS: The feasibility phase of the COG IR-RMS trial, ARST1431 (NCT02567435), assigned 10 patients to receive 15 mg/m2 /dose (dose level 1) of temsirolimus on days 1, 8, and 15 of each of three weekly VAC and VI cycles for the first 12 weeks of induction chemotherapy. The primary endpoint of the feasibility phase was to establish the safe dose and safety of combining temsirolimus with VAC/VI. The combination regimen was deemed feasible if less than 40% of patients developed a priori defined nonhematological dose-limiting toxicities (DLTs). RESULTS: Ten patients (seven males and three females; median age = 4.5 years [range: 0.2-14.4 years]) with IR-RMS were enrolled and received dose level 1 of temsirolimus. Eight patients had FOXO1-negative disease, while two had FOXO1-positive disease. Two patients had metastatic disease. Of 10 patients, two developed DLTs: grade 3 oral mucositis and pneumonitis. Four patients (40%) had grade 4 neutropenia. No treatment-related mortality occurred. The median duration of the completion of the feasibility phase was 12.1 weeks (range: 11.7-15 weeks). CONCLUSIONS: Weekly temsirolimus at 15 mg/m2 /dose during VAC/VI chemotherapy was feasible and well tolerated. The efficacy of this regimen is currently being tested in a phase III randomized trial against VAC/VI chemotherapy alone in the ARST1431 trial.

Impact of Biomarker-Matched Therapies on Outcomes in Patients with Sarcoma Enrolled in Early-Phase Clinical Trials (SAMBA 101).

PURPOSE: Developing new therapeutics for any of the more than 100 sarcoma subtypes presents a challenge. After progression from standard therapies, patients with sarcoma may be referred for enrollment in early-phase trials. This study aimed to investigate whether enrollment in biomarker-matched early-phase clinical trials leads to better outcomes for patients with advanced sarcoma. EXPERIMENTAL DESIGN: In this retrospective analysis, investigational treatment characteristics and longitudinal survival outcomes were analyzed in patients with biopsy-confirmed sarcoma enrolled in early-phase trials at MD Anderson Cancer Center from May 2006 to July 2021. RESULTS: Five hundred eighty-seven patients were included [405 soft tissue, 122 bone, 60 gastrointestinal stromal tumor (GIST); median of three prior lines of therapy]. Most common subtypes were leiomyosarcoma (17.2%), liposarcoma (14.0%), and GIST (10.2%). Molecular testing was available for 511 patients (87.1%); 221 patients (37.6%) were treated in matched trials. Overall response rate was 13.1% matched compared with 4.9% in unmatched (P < 0.001); the clinical benefit rate at 6 months was 43.9% vs. 19.9% (P < 0.001). Progression-free survival was longer for patients in matched trials (median, 5.5 vs. 2.4 months; P < 0.001), and overall survival was also superior for patients in matched trials (median, 21.5 vs. 12.3 months; P < 0.001). The benefit of enrollment in matched trials was maintained when patients with GIST were excluded from the analysis. CONCLUSIONS: Enrollment in biomarker-matched early-phase trials is associated with improved outcomes in heavily pretreated patients with metastatic sarcoma. Molecular testing of tumors from patients with advanced sarcoma and enrollment in matched trials is a reasonable therapeutic strategy.

APOE4 drives transcriptional heterogeneity and maladaptive immunometabolic responses of astrocytes.

Apolipoprotein E4 (APOE4) is the strongest risk allele associated with the development of late onset Alzheimer's disease (AD). Across the CNS, astrocytes are the predominant expressor of APOE while also being critical mediators of neuroinflammation and cerebral metabolism. APOE4 has been consistently linked with dysfunctional inflammation and metabolic processes, yet insights into the molecular constituents driving these responses remain unclear. Utilizing complementary approaches across humanized APOE mice and isogenic human iPSC astrocytes, we demonstrate that ApoE4 alters the astrocyte immunometabolic response to pro-inflammatory stimuli. Our findings show that ApoE4-expressing astrocytes acquire distinct transcriptional repertoires at single-cell and spatially-resolved domains, which are driven in-part by preferential utilization of the cRel transcription factor. Further, inhibiting cRel translocation in ApoE4 astrocytes abrogates inflammatory-induced glycolytic shifts and in tandem mitigates production of multiple pro-inflammatory cytokines. Altogether, our findings elucidate novel cellular underpinnings by which ApoE4 drives maladaptive immunometabolic responses of astrocytes.

Evaluation of the pan-class I phosphoinositide 3-kinase (PI3K) inhibitor copanlisib in the Pediatric Preclinical Testing Consortium in vivo models of osteosarcoma.

Copanlisib is a pan-class I phosphoinositide 3-kinase (PI3K) inhibitor, with activity against all four PI3K class I isoforms (PI3Kα, PI3Kß, PI3Kγ, and PI3Kδ). Whole-genome and RNA sequencing data have revealed several PI3K aberrations in osteosarcoma tumor samples. The in vivo anticancer effects of copanlisib were assessed in a panel of six osteosarcoma models. Copanlisib induced prolonged event-free survival in five of six osteosarcoma models; however, all models demonstrated progressive disease suggesting minimal activity. While copanlisib did not result in tumor regression, more data are needed to fully explore the role of the PI3K pathway in the pathogenesis of osteosarcoma.

Renal function in abdominal neuroblastoma patients undergoing proton radiotherapy.

BACKGROUND: The purpose of this study is to analyze renal function outcomes in abdominal neuroblastoma patients undergoing proton therapy (PT). PROCEDURE: From 2011 to 2019, two single-institution Institutional Review Board-approved protocols prospectively enrolled neuroblastoma patients for data collection. To assess renal function, serum creatinine (Cr), blood urea nitrogen (BUN), and creatinine clearance (CrCl) before proton therapy (pre-PT) were compared with the values at last follow-up. RESULTS: A total of 30 children with abdominal neuroblastoma with median age 3.5 years (range, 0.9-9.1) at time of PT were included in this study. All patients underwent chemotherapy and resection of primary tumor prior to PT. Two patients required radical nephrectomy. Median follow-up after PT was 35 months. Mean dose to ipsilateral and contralateral kidney was 13.9 and 5.4 Gy, respectively. No patients developed hypertension or renal dysfunction during follow-up. There was no statistically significant change in serum BUN (p = .508), CrCl (p = .280), or eGFR (p = .246) between pre-PT and last follow-up. CONCLUSION: At a median follow-up of almost 3 years, renal toxicity was uncommon after PT. Longer follow-up and larger patient cohort data are needed to further assess impact of PT on renal function in this population.

Trastuzumab Deruxtecan, Antibody-Drug Conjugate Targeting HER2, Is Effective in Pediatric Malignancies: A Report by the Pediatric Preclinical Testing Consortium.

HER2 is expressed in many pediatric solid tumors and is a target for innovative immune therapies including CAR-T cells and antibody-drug conjugates (ADC). We evaluated the preclinical efficacy of trastuzumab deruxtecan (T-DXd, DS-8201a), a humanized monoclonal HER2-targeting antibody conjugated to a topoisomerase 1 inhibitor, DXd, in patient- and cell line-derived xenograft (PDX/CDX) models. HER2 mRNA expression was determined using RNA-seq and protein expression via IHC across multiple pediatric tumor PDX models. Osteosarcoma (OS), malignant rhabdoid tumor (MRT), and Wilms tumor (WT) models with varying HER2 expression were tested using 10 mice per group. Additional histologies such as Ewing sarcoma (EWS), rhabdomyosarcoma (RMS), neuroblastoma (NB), and brain tumors were evaluated using single mouse testing (SMT) experiments. T-DXd or vehicle control was administered intravenously to mice harboring established flank tumors at a dose of 5 mg/kg on day 1. Event-free survival (EFS) and objective response were compared between treatment and control groups. HER2 mRNA expression was observed across histologies, with the highest expression in WT (median = 22 FPKM), followed by MRT, OS, and EWS. The relationship between HER2 protein and mRNA expression was inconsistent. T-DXd significantly prolonged EFS in 6/7 OS, 2/2 MRT, and 3/3 WT PDX models. Complete response (CR) or maintained CR (MCR) were observed for 4/5 WT and MRT models, whereas stable disease was the best response among OS models. SMT experiments also demonstrated activity across multiple solid tumors. Clinical trials assessing the efficacy of a HER2-directed ADC in pediatric patients with HER2-expressing tumors should be considered.

Cerium dioxide, a Jekyll and Hyde nanomaterial, can increase basal and decrease elevated inflammation and oxidative stress.

It was hypothesized that the catalyst nanoceria can increase inflammation/oxidative stress from the basal and reduce it from the elevated state. Macrophages clear nanoceria. To test the hypothesis, M0 (non-polarized), M1- (classically activated, pro-inflammatory), and M2-like (alternatively activated, regulatory phenotype) RAW 264.7 macrophages were nanoceria exposed. Inflammatory responses were quantified by IL-1ß level, arginase activity, and RT-qPCR and metabolic changes and oxidative stress by the mito and glycolysis stress tests (MST and GST). Morphology was determined by light microscopy, macrophage phenotype marker expression, and a novel three-dimensional immunohistochemical method. Nanoceria blocked IL-1ß and arginase effects, increased M0 cell OCR and GST toward the M2 phenotype and altered multiple M1- and M2-like cell endpoints toward the M0 level. M1-like cells had greater volume and less circularity/roundness. M2-like cells had greater volume than M0 macrophages. The results are overall consistent with the hypothesis.

Mechanotherapy Reprograms Aged Muscle Stromal Cells to Remodel the Extracellular Matrix during Recovery from Disuse.

Aging is accompanied by reduced remodeling of skeletal muscle extracellular matrix (ECM), which is exacerbated during recovery following periods of disuse atrophy. Mechanotherapy has been shown to promote ECM remodeling through immunomodulation in adult muscle recovery, but not during the aged recovery from disuse. In order to determine if mechanotherapy promotes ECM remodeling in aged muscle, we performed single cell RNA sequencing (scRNA-seq) of all mononucleated cells in adult and aged rat gastrocnemius muscle recovering from disuse, with (REM) and without mechanotherapy (RE). We show that fibroadipogenic progenitor cells (FAPs) in aged RE muscle are highly enriched in chemotaxis genes (Csf1), but absent in ECM remodeling genes compared to adult RE muscle (Col1a1). Receptor-ligand (RL) network analysis of all mononucleated cell populations in aged RE muscle identified chemotaxis-enriched gene expression in numerous stromal cell populations (FAPs, endothelial cells, pericytes), despite reduced enrichment of genes related to phagocytic activity in myeloid cell populations (macrophages, monocytes, antigen presenting cells). Following mechanotherapy, aged REM mononuclear cell gene expression resembled adult RE muscle as evidenced by RL network analyses and KEGG pathway activity scoring. To validate our transcriptional findings, ECM turnover was measured in an independent cohort of animals using in vivo isotope tracing of intramuscular collagen and histological scoring of the ECM, which confirmed mechanotherapy-mediated ECM remodeling in aged RE muscle. Our results highlight age-related cellular mechanisms underpinning the impairment to complete recovery from disuse, and also promote mechanotherapy as an intervention to enhance ECM turnover in aged muscle recovering from disuse.

Clinical group and modified TNM stage for rhabdomyosarcoma: A review from the Children's Oncology Group.

The Children's Oncology Group (COG) uses Clinical Group (CG) and modified Tumor Node Metastasis (TNM) stage to classify rhabdomyosarcoma (RMS). CG is based on surgicopathologic findings and is determined after the completion of initial surgical procedure(s) but prior to chemotherapy and/or radiation therapy. The modified TNM stage is based on clinical and radiographic findings and is assigned prior to any treatment. These systems have evolved over several decades. We review the history, evolution, and rationale behind the current CG and modified TNM classification systems used by COG for RMS. Data from the seven most recently completed and reported frontline COG trials (D9602, D9802, D9803, ARST0331, ARST0431, ARST0531, ARST08P1) were analyzed, and confirm that CG and modified TNM stage remain relevant and useful for predicting prognosis in RMS. We propose updates based on recent data and discuss factors warranting future study to further optimize these classification systems.

Comprehensive Surfaceome Profiling to Identify and Validate Novel Cell-Surface Targets in Osteosarcoma.

Immunoconjugates targeting cell-surface antigens have demonstrated clinical activity to enable regulatory approval in several solid and hematologic malignancies. We hypothesize that a rigorous and comprehensive surfaceome profiling approach to identify osteosarcoma-specific cell-surface antigens can similarly enable development of effective therapeutics in this disease. Herein, we describe an integrated proteomic and transcriptomic surfaceome profiling approach to identify cell-surface proteins that are highly expressed in osteosarcoma but minimally expressed on normal tissues. Using this approach, we identified targets that are highly expressed in osteosarcoma. Three targets, MT1-MMP, CD276, and MRC2, were validated as overexpressed in osteosarcoma. Furthermore, we tested BT1769, an MT1-MMP-targeted Bicycle toxin conjugate, in osteosarcoma patient-derived xenograft models. The results showed that BT1769 had encouraging antitumor activity, high affinity for its target, and a favorable pharmacokinetic profile. This confirms the hypothesis that our approach identifies novel targets with significant therapeutic potential in osteosarcoma.