Metastatic Neuroblastoma Research Articles

123I]-metaiodobenzylguanidine imaging findings and outcome in patients with metastatic neuroblastoma

Background: 123I-Metaiodobenzylguanidine ([123I]mIBG) is the agent of choice to assess for presence of metastases and therapy response in patients with neuroblastoma.Aim: To assess [123I]mIBG scan results and outcome in patients with stage 4 neuroblastoma at our institution.Setting: Red Cross War Memorial Children’s Hospital.Methods: A retrospective review of baseline and follow-up [123I]mIBG scans of patients who presented between January 2001 and May 2015. The clinical follow up extended until October 2019. The association between the baseline and post-induction Curie score (CS) and overall survival (OS) were assessed.Results: Thirty-four patients with stage 4 disease were included. Twenty-two (65%) patients died. The median age at diagnosis for survivors was 15.5 months vs 39 months for those who died (Kruskal Wallis c2 = 4.63, p = 0.03). Neither the baseline CS nor the post-induction CS predict the outcome or duration of survival. The median OS for a baseline CS ≤ 12 and CS 12 was 19 and 26 months, p = 0.13. The median OS for a post-induction CS 2 and CS ≤ 2 was 28 and 26 months, p = 0.66.Conclusion: In this study, baseline, post-induction and reduction in CS did not predict OS in stage 4 neuroblastoma. Factors such as small patient numbers, less intensive treatment regimes, and possible poorly dedifferentiated disease have been identified for this finding.Contribution: In contrast to international studies the Curie score did not predict treatment outcome in the South African setting where the vast majority of patients are treated with OPEC/OJEC OPEC/OJEC (vincristine [O], cisplatin [P], etoposide [E], cyclophosphamide [C] and carboplatin [J]) chemotherapy.

Identification of a novel eighteen-gene signature of recurrent metastasis neuroblastoma.

Neuroblastoma is the most common malignant tumor in childhood, and metastases occur in more than 30% patients. Recurrent metastasis is the main cause of poor prognosis and high mortality in neuroblastoma. In this regard, there is still a lack of sufficient biomarkers and effective therapies. Therefore, we performed a multi-omics analysis of neuroblastoma patients from Therapeutically Applicable Research To Generate Effective Treatments (TARGET). With clinical relapse site information, tumor samples derived from the primary site were divided into recurrent metastasis and primary tumor groups. The initial gene signature was obtained by comparing RNA-Seq and copy number variation differences. Survival data was used to further filter prognosis-related genes. This 18-gene signature consists of three clusters: tumor suppression, cell proliferation, and immunity. A super enhancer is involved in the enhanced expression of NCAPG in cluster2 together with IRF3. Based on the gene signature expression in primary neuroblastoma, it is possible to predict tumor metastasis before it occurs. According to the anticancer drug dataset of Genomics of Drug Sensitivity in Cancer (GDSC), vinorelbine and docetaxel were predicted to have high sensitivity against recurrent metastatic neuroblastoma. In conclusion, our study offers a novel metastasis biomarker and helps understand the mechanisms of tumor recurrent metastasis. KEY MESSAGES: We identified a novel eighteen-gene signature of recurrent metastasis neuroblastoma and build risk and classification models. We dissected the regulatory role of NCAPG in signatures. We found immune exhaustion and immunosuppression in recurrent metastasis neuroblastoma. Vinorelbine and docetaxel were predicted to have high sensitivity against recurrent metastatic neuroblastoma.

Multiple subcutaneous nodules leading to a diagnosis of metastatic neuroblastoma in an infant: A case report

Neuroblastoma is a childhood malignancy with protean clinical manifestations. One rare presentation is multiple cutaneous nodules, especially in infants. We present a case of multiple cutaneous nodules as the initial presentation in an infant with metastatic neuroblastoma. The patient received chemotherapy with good response and is alive and well 5 years post diagnosis.

Effect of Oral β-Glucan on Antibody Response to Ganglioside Vaccine in Patients With High-Risk Neuroblastoma

Among patients with high-risk relapsed metastatic neuroblastoma, oral β-glucan adjuvant during GD2/GD3 ganglioside vaccine boost has stimulated IgG antibody response, which was associated with improved survival; however, the effectiveness of oral β-glucan during the vaccine priming phase remains unproven. To isolate the adjuvant effect of oral β-glucan on antibody response to GD2/GD3 ganglioside vaccine in patients with high-risk neuroblastoma. In this phase 2 randomized clinical trial, enrolled patients with high-risk neuroblastoma were randomized to 2 groups to receive the GD2/GD3 vaccine at a large cancer center in a major metropolitan area from October 2018 to September 2020. Data were analyzed from October 7, 2021, to February 28, 2022. Eligible patients receiving GD2/GD3 vaccine were randomly assigned to group 1 (n = 54) to receive no β-glucan or group 2 (n = 53) to receive an oral β-glucan regimen during the first 5 weeks of vaccine priming. From week 6 onwards, all 107 patients received oral β-glucan during vaccine boost for 1 year or until disease progression. Primary end point was comparison of anti-GD2 IgG1 response before vaccine injection 6 (week 32) in group 1 vs group 2. Seroconversion rate and the association of antibody titer with β-glucan receptor dectin-1 single nucleotide polymorphism (SNP) rs3901533 were also assessed. In all, 107 patients with high-risk neuroblastoma were randomized to the 2 groups: 54 patients (median [range] age, 5.2 [1.0-17.3] years; 28 [52%] male and 26 [48%] female) in group 1; and 53 patients (median [range] age, 6.2 [1.9-18.4] years; 25 [47%] male and 28 [53%] female) in group 2; both groups were also comparable in their first remission status at study entry (70% vs 70%). Adding oral β-glucan during the first 5 weeks of vaccine priming elicited a higher anti-GD2 IgG1 antibody response in group 2 (1.80; 90% CI, 0.12-3.39; P = .08; planned type I error, 0.10). Anti-GD2 IgG1 titer of 230 ng/mL or greater by week 8 was associated with statistically favorable PFS. Antibody titer correlated significantly with dectin-1 SNP. The genotype frequency, seroconversion rates, and vaccine-related toxic effects were similar in the 2 groups. This phase 2 randomized clinical trial found that adding oral β-glucan during vaccine priming increased anti-GD2 IgG1 titer among genetic responders without added toxic effects. Because responder dectin-1 SNP was identical in the 2 randomized groups, no difference was detected in seroconversion rates. Alternative or additional adjuvants may be needed to enhance seroconversion. ClinicalTrials.gov Identifier: NCT00911560.

An atypical imaging characteristic of calvarial metastasis of neuroblastoma as multiple multi-loculated cystic masses with internal blood-fluid levels: a case report

As the third most common malignancy of childhood, Neuroblastoma has a great propensity to metastasize to multiple organs. The most common site of metastasis is the bone and bone marrow. Concerning the central nervous system, neuroblastoma usually involves the calvarium and the external dural surface. The skull metastases may show different appearances, including: multiple lytic bone lesions, bone thickening, hair-on-end periosteal reaction, irregular suture widening and/or plaque like epidural deposits. Here we present a case of metastatic neuroblastoma, appearing as multiple multi-loculated cystic epidural masses with internal blood-fluid levels as a rare imaging manifestation of calvarial metastasis. An 8-year-old boy with known history of autism, presented to the emergency department with a 3-month history of intermittent fever, malaise and myalgia and headache along with significant weight loss. Laboratory examination revealed elevated ESR and CRP and anemia. On Abdomino-Pelvic imaging a well-defined, 45*30*24mm, solid-cystic mass was observed, replacing the normal left adrenal gland. On brain MRI, multiple multi-loculated cystic, lentiform masses were observed on the external surface of cerebral hemispheric dura. Multiple fluid-fluid levels were noted in the locules in some of which the dependent fluid was hyperintense on T1w and FLAIR and hypointense on T2w sequences, compatible with blood, representing blood-fluid level. The wall and septa of the masses, enhanced after contrast administration. Associated abnormal marrow signal and aggressive type periosteal reactions were identified in the overlying bone. All of the lesions had increased uptake in MIBG scan. Bone marrow biopsy revealed small round cells, diagnostic for neuroblastoma. The patient underwent chemotherapy treatment. All calvarial/epidural metastatic lesions resolved after chemotherapy and residual adrenal tumor was resected. Cystic epidural lesions, especially when associated with adjacent abnormal bone marrow signal, or periosteal reaction and containing blood-fluid level should raise the suspicion of a calvarial metastasis.

Phase 1 study of intraventricular 131I-omburtamab targeting B7H3 (CD276)-expressing CNS malignancies

BackgroundThe prognosis for metastatic and recurrent tumors of the central nervous system (CNS) remains dismal, and the need for newer therapeutic targets and modalities is critical. The cell surface glycoprotein B7H3 is expressed on a range of solid tumors with a restricted expression on normal tissues. We hypothesized that compartmental radioimmunotherapy (cRIT) with the anti-B7H3 murine monoclonal antibody omburtamab injected intraventricularly could safely target CNS malignancies.Patients and methodsWe conducted a phase I trial of intraventricular 131I-omburtamab using a standard 3 + 3 design. Eligibility criteria included adequate cerebrospinal fluid (CSF) flow, no major organ toxicity, and for patients > dose level 6, availability of autologous stem cells. Patients initially received 74 MBq radioiodinated omburtamab to evaluate dosimetry and biodistribution followed by therapeutic 131I-omburtamab dose-escalated from 370 to 2960 MBq. Patients were monitored clinically and biochemically for toxicity graded using CTCAEv 3.0. Dosimetry was evaluated using serial CSF and blood sampling, and serial PET or gamma-camera scans. Patients could receive a second cycle in the absence of grade 3/4 non-hematologic toxicity or progressive disease.ResultsThirty-eight patients received 100 radioiodinated omburtamab injections. Diagnoses included metastatic neuroblastoma (n = 16) and other B7H3-expressing solid tumors (n = 22). Thirty-five patients received at least 1 cycle of treatment with both dosimetry and therapy doses. Acute toxicities included < grade 4 self-limited headache, vomiting or fever, and biochemical abnormalities. Grade 3/4 thrombocytopenia was the most common hematologic toxicity. Recommended phase 2 dose was 1850 MBq/injection. The median radiation dose to the CSF and blood by sampling was 1.01 and 0.04 mGy/MBq, respectively, showing a consistently high therapeutic advantage for CSF. Major organ exposure was well below maximum tolerated levels. In patients developing antidrug antibodies, blood clearance, and therefore therapeutic index, was significantly increased. In patients receiving cRIT for neuroblastoma, survival was markedly increased (median PFS 7.5 years) compared to historical data.ConclusionscRIT with 131I-omburtamab is safe, has favorable dosimetry and may have a therapeutic benefit as adjuvant therapy for B7-H3-expressing leptomeningeal metastases.Trial registration: clinicaltrials.gov NCT00089245, August 5, 2004.

Clinical and biological features prognostic of survival after relapse or progression of INRGSS stage MS pattern neuroblastoma: A report from the International Neuroblastoma Risk Group (INRG) project.

Outcomes for patients with INRGSS metastatic special (MS) metastatic pattern neuroblastoma at initial diagnosis are well described. Prognosis after an initial event (relapse, progression, secondary malignancy) is unclear. We investigated characteristics of MS pattern neuroblastoma patients in the International Neuroblastoma Risk Group database who subsequently experienced an event. Post-event overall survival (OS)±standard error was calculated overall and by diagnosis era: before 2000 versus 2001 or after. Cox models were used to identify factors prognostic of post-event OS. Among 209 patients with an event, 88% were less than 365days old at diagnosis; tumors were MYCN amplified in 24% and diploid in 33%. The median (range) time from diagnosis to first event was 8.16months (7days to 11.24years). Of 96 patients with known relapse/progression pattern, 75% were metastatic or primary plus metastatic. Five-year post-event OS was 53%±3.6% and was higher for 2001 and afterwards (62%±5.0%) compared to before 2001 (44%±4.9%; p=.0046). In patients diagnosed in 2001 and after, older age, Hispanic ethnicity, MYCN amplification, 1p LOH, diploidy, high Mitotic Karyorrhexis Index, high lactate dehydrogenase (LDH), unfavorable histology, and longer time to first event were prognostic of worse post-event OS. Independent adverse prognostic factors on multivariable testing were non-White race, MYCN amplification, and diploidy. Patients diagnosed in and after 2001 have substantially better post-event OS compared to before 2001. In those diagnosed in and after 2001, most well-accepted prognostic factors for OS at diagnosis are also prognostic of post-event OS. Future studies may evaluate strategies to improve outcomes in this rare population.

Patterns of Failure in High-Risk Neuroblastoma with or without Metastatic Site Irradiation

<h3>Purpose/Objective(s)</h3> Neuroblastoma is the most common extracranial malignancy diagnosed in childhood. Despite recent improvements in outcomes and an overall 5-year survival of >80%, the majority of children with high-risk neuroblastoma will relapse despite aggressive treatment. As part of their treatment paradigm, radiation treatment (RT) is recommended to the primary site after surgery, as well as to metastatic sites of disease that continue to be metaiodobenzylguanidine (MIBG)-avid post-induction chemotherapy. While there is an abundance of data supporting the former, data is limited on the role of RT to metastatic sites and thus our practice has generally been to withhold RT to metastatic sites. The aim of this study is to examine patterns of failure in patients with high-risk metastatic neuroblastoma to better determine the value of metastatic site RT. <h3>Materials/Methods</h3> We performed an IRB-approved retrospective review from our institutional database of patients with high-risk neuroblastoma who were treated from 2010-2020. The included patients had MIBG-avid metastatic disease at the time of diagnosis, as well as first relapse. These patients achieved a partial or complete response before first relapse, and did not receive total body radiation or therapy with ¹³¹I-MIBG prior to first relapse. We analyzed the patients who failed and compared the anatomical location of all sites at initial relapse to sites that were MIBG-avid on post-induction chemotherapy scan. <h3>Results</h3> With a median follow up of 38 months, 13 of the 41 patients (32%) treated during this time recurred, and 5 (12%) died. 3 patients who recurred were excluded from the analysis as they did not have sufficient records. Of the 10 patients analyzed with recurrent disease, there were 70 MIBG-avid metastatic sites on post-induction chemotherapy scan, and of these only 11 (16%) received RT. There were 13 total MIBG-avid metastatic sites at time of first recurrence, of which 6 (46%) were in original site present on post-induction chemo MIBG scan, 1 which received radiation treatment and the other 5 (38%) did not. Of the sites that did receive radiation treatment, 10/11 (91%) did not recur. In analysis per patient, 4/10 (40%) recurred initially in metastatic sites that were MIBG-avid on post-induction scan, while the remaining majority recurred in both initial and new sites or new sites only. <h3>Conclusion</h3> In this unique cohort of high-risk neuroblastoma patients who mostly did not receive RT to post-induction chemotherapy MIGB-avid metastatic sites, a little less than half of the patients and sites relapsed in initial areas, while the remaining relapsed at new sites. Those sites that were treated with RT had excellent local control >90%, consistent with prior reports. While this data suggests that RT to metastatic sites on post-induction chemotherapy MIBG scan may improve outcomes, the sample size is limited and caution must be taken to balance potential benefits with risks, especially in situations with several metastatic sites.

The pre-surgical factors that determine the decision to proceed to resection in children diagnosed with high-risk neuroblastoma in a resource limited setting

Surgical control has prognostic value in neuroblastoma (NB). Advanced NB is common at diagnosis in South Africa. We investigated the pre-surgery factors that influenced decisions to perform surgical resections. We included 204 patients with high-risk NB from a national retrospective study, who completed induction chemotherapy between 2000 and 2016. The median age was 32.4 months (IQR 15.1 − 53.5 months). Primary tumor resection was achieved in 76.9% of patients between 0-18 months of age, 51.8% between 18-60 months and 51.7% older than 60 months (p < 0.001). Only 43.2% of patients with distant metastatic disease had surgery done (p < 0.001). LDH was >750 U/L in 46.8% and ferritin >120 g/dL in 53.1% of those who had surgery (p = 0.005). The majority (80.4%), who had achieved post-induction metastatic complete remission (mCR), were operated, while 28.7% without mCR had surgery (p < 0.001). The long-term overall survival in patients with mCR and primary tumor resection was 36.5% compared to those with mCR without primary tumor resection (25.4%) and without mCR (≤3.0%)(p < 0.001). Age (p < 0.001), stage (p < 0.001), mCR (p < 0.001) and treatment setting (p < 0.001) were of prognostic significance. The tumor site and MYCN-amplification did not significantly predict resection rates. Post-induction mCR and stage were associated with surgical resection and five-year OS (p < 0.001) on multivariate analysis. Patients with high-risk NB who achieved mCR and had primary tumor resections are curable in limited resourced settings. Stage and post-induction mCR were significant variables that led to surgery. These variables should be included as indications in the management of metastatic NB in resource limited settings.

Structural disruption of BAF chromatin remodeller impairs neuroblastoma metastasis by reverting an invasiveness epigenomic program

BackgroundEpigenetic programming during development is essential for determining cell lineages, and alterations in this programming contribute to the initiation of embryonal tumour development. In neuroblastoma, neural crest progenitors block their course of natural differentiation into sympathoadrenergic cells, leading to the development of aggressive and metastatic paediatric cancer. Research of the epigenetic regulators responsible for oncogenic epigenomic networks is crucial for developing new epigenetic-based therapies against these tumours. Mammalian switch/sucrose non-fermenting (mSWI/SNF) ATP-dependent chromatin remodelling complexes act genome-wide translating epigenetic signals into open chromatin states. The present study aimed to understand the contribution of mSWI/SNF to the oncogenic epigenomes of neuroblastoma and its potential as a therapeutic target.MethodsFunctional characterisation of the mSWI/SNF complexes was performed in neuroblastoma cells using proteomic approaches, loss-of-function experiments, transcriptome and chromatin accessibility analyses, and in vitro and in vivo assays.ResultsNeuroblastoma cells contain three main mSWI/SNF subtypes, but only BRG1-associated factor (BAF) complex disruption through silencing of its key structural subunits, ARID1A and ARID1B, impairs cell proliferation by promoting cell cycle blockade. Genome-wide chromatin remodelling and transcriptomic analyses revealed that BAF disruption results in the epigenetic repression of an extensive invasiveness-related expression program involving integrins, cadherins, and key mesenchymal regulators, thereby reducing adhesion to the extracellular matrix and the subsequent invasion in vitro and drastically inhibiting the initiation and growth of neuroblastoma metastasis in vivo.ConclusionsWe report a novel ATPase-independent role for the BAF complex in maintaining an epigenomic program that allows neuroblastoma invasiveness and metastasis, urging for the development of new BAF pharmacological structural disruptors for therapeutic exploitation in metastatic neuroblastoma.

Anti-proliferation and apoptosis-inducing effects of dihydroartemisinin on SH-SY5Y cells and metabolomic analysis

BackgroundIn childhood, metastatic neuroblastoma (NB) is the most common extracranial solid tumor, but there are no appropriate drugs for its treatment. Dihydroartemisinin (DHA), a drug for malaria treatment, has therapeutic potential in several cancers; however, its mechanisms remain unclear. This study aimed to investigate the anti-proliferation effect of DHA on SH-SY5Y cells and to explore its mechanism in vitro.MethodsWe used 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay to measure the half-maximal inhibitory concentration (IC50) of DHA; western blot was used to determine protein levels; propidium iodide (PI) staining was used to determine apoptotic cells; JC-1 staining to measure mitochondrial membrane potential; and dichloro-dihydro-fluorescein diacetate (DCFH-DA) staining was used to determine reactive oxygen species (ROS). Metabonomic analysis was performed by using ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS)-based untargeted metabolomics. Multivariate statistical analysis was performed to screen potential metabolites associated with DHA treatment in SH-SY5Y cells.ResultsIt was shown that DHA inhibited SH-SY5Y cell proliferation and increased poly (ADP-ribose) polymerase (PARP-1) and caspase 3 in a dose-dependent manner. In Further, DHA promoted ROS generation and γH2AX expression. In addition, a total of 125 proposed metabolites in SH-SY5Y cells and 45 vital metabolic pathways were identified through UHPLC-MS/MS-based untargeted metabolomic analysis.ConclusionsThese data suggest that DHA could regulate taurine, linoleic acid, phenylalanine metabolism, and tryptophan metabolism, which are involved in the anti-proliferation effect of DHA in SH-SY5Y cells.

Targeted parallel DNA sequencing detects circulating tumor-associated variants of the mitochondrial and nuclear genomes in patients with neuroblastoma.

The utility for liquid biopsy of tumor-associated circulating single-nucleotide variants, as opposed to mutations, of the mitochondrial (mt) and nuclear genomes in neuroblastoma (NB) is unknown. Variants of the mt and nuclear genomes from tumor, blood cells, and consecutive plasma samples of five patients with metastatic NB that relapsed or progressed were analyzed. Targeted parallel sequencing results of the mt genome, and of the coding region of 139 nuclear genes and 22 miRNAs implicated in NB, were correlated with clinical imaging and laboratory data. All tumors harbored multiple somatic mt and nuclear single nucleotide variants with low allelic frequency, most of them not detected in the circulation. In one patient a tumor-associated mt somatic variant was detected in the plasma before and during progressive disease. In a second patient a circulating nuclear tumor-associated DNA variant heralded clinical relapse. In all patients somatic mt and nuclear variants not evident in the tumor biopsy at time of diagnosis were found circulating at varying timepoints. This suggests either tumor heterogeneity, evolution of tumor variants or a confounding contribution of normal tissues to somatic variants in patient plasma. The number and allelic frequency of the circulating variants did not reflect the clinical course of the tumors. Mutational signatures of mt and nuclear somatic variants differed. They varied between patients and were detected in the circulation without mirroring the patients' course. In this limited cohort of NB patients clinically informative tumor-associated mt and nuclear circulating variants were detected by targeted parallel sequencing in a minority of patients.

Spectrum of paired-like homeobox 2b immunoexpression in pediatric brain tumors with embryonal morphology.

Paired‐like homeobox 2b (PHOX2B) is an established immunomarker for peripheral neuroblastoma and autonomic nervous system cells. We aimed to evaluate the utility of PHOX2B immunostaining in central nervous system (CNS) tumors with embryonal morphology. Fifty‐one tumors were stained with PHOX2B and submitted for whole slide image analysis: 35 CNS tumors with embryonal morphology (31 CNS embryonal tumors and four gliomas); and 16 peripheral neuroblastomas were included for comparison. Diffuse nuclear immunopositivity was observed in all (16/16) neuroblastomas (primary and metastatic). Among CNS embryonal tumors, focal immunoreactivity for PHOX2B was observed in most (5/7) embryonal tumors with multilayered rosettes (ETMR) and a single high‐grade neuroepithelial tumor (HGNET) with PLAGL2 amplification; the remaining 27 CNS tumors were essentially immunonegative (<0.05% positive). Among ETMR, PHOX2B expression was observed in a small overall proportion (0.04%–4.94%) of neoplastic cells but focally reached up to 39% in 1 mm ‘hot spot’ areas. In the PLAGL2‐amplified case, 0.09% of the total neoplastic population was immunoreactive, with 0.53% in the ‘hot spot’ area. Care should be taken in interpreting PHOX2B immunopositivity in a differential diagnosis that includes metastatic neuroblastoma and CNS tumors; focal or patchy expression should not be considered definitively diagnostic of metastatic peripheral neuroblastoma.

MIF/CXCR4 signaling axis contributes to survival, invasion, and drug resistance of metastatic neuroblastoma cells in the bone marrow microenvironment

BackgroundThe bone marrow (BM) is the most common site of dissemination in patients with aggressive, metastatic neuroblastoma (NB). However, the molecular mechanisms underlying the aggressive behavior of NB cells in the BM niche are still greatly unknown. In the present study, we explored biological mechanisms that play a critical role in NB cell survival and progression in the BM and investigated potential therapeutic targets.MethodsPatient-derived bone marrow (BM) primary cultures were generated using fresh BM aspirates obtained from NB patients. NB cell lines were cultured in the presence of BM conditioned media containing cell-secreted factors, and under low oxygen levels (1% O2) to mimic specific features of the BM microenvironment of high-risk NB patients. The BM niche was explored using cytokine profiling assays, cell migration-invasion and viability assays, flow cytometry and analysis of RNA-sequencing data. Selective pharmacological inhibition of factors identified as potential mediators of NB progression within the BM niche was performed in vitro and in vivo.ResultsWe identified macrophage migration inhibitory factor (MIF) as a key inflammatory cytokine involved in BM infiltration. Cytokine profiling and RNA-sequencing data analysis revealed NB cells as the main source of MIF in the BM, suggesting a potential role of MIF in tumor invasion. Exposure of NB cells to BM-conditions increased NB cell-surface expression of the MIF receptor CXCR4, which was associated with increased cell viability, enhanced migration-invasion, and activation of PI3K/AKT and MAPK/ERK signaling pathways. Moreover, subcutaneous co-injection of NB and BM cells enhanced tumor engraftment in mice. MIF inhibition with 4-IPP impaired in vitro NB aggressiveness, and improved drug response while delayed NB growth, improving survival of the NB xenograft model.ConclusionsOur findings suggest that BM infiltration by NB cells may be mediated, in part, by MIF-CXCR4 signaling. We demonstrate the antitumor efficacy of MIF targeting in vitro and in vivo that could represent a novel therapeutic target for patients with disseminated high-risk NB.

Abstract 1121: Identification and in vivo validation of unique anti-oncogenic properties and mechanisms involving protein kinase signalling and autophagy mediated by the investigational new agent PV-10

Abstract Introduction: PV-10 (10% Rose Bengal) is a small molecule agent previously shown to have potent immunotherapeutic and anti-tumor activities against a number of tumors including metastatic melanoma and refractory neuroblastoma, and is currently undergoing clinical testing as a single-agent for refractory metastatic neuroendocrine cancer (NCT02693067) and in combination with checkpoint inhibitors for metastatic melanoma (NCT02557321) and metastatic uveal melanoma (NCT00986661). We have previously determined that PV-10 induces cell death at pharmacologically relevant concentrations in a panel of phenotypically diverse adult solid tumor cell lines. However, the molecular consequences of this phenomenon have not yet been fully elucidated. In this study, we investigated the target validation and modulation of PV-10 on protein kinase signalling and their associated impact on specific oncogenic pathways in these tumor cells. Methods: A panel of human tumor cell lines derived from breast (MCF-7, T-47D, MDA-MB-231), colorectal (LoVo, T-84), head and neck (CAL-27, Detroit-562, FaDu, UM-SCC-1), and testicular (NCC-IT, NTERA-2, TCAM-2) tissues were treated with PV-10 and their cytotoxic and pro-apoptotic effects were described. Protein kinase profiling was performed using the human phospho-kinase antibody array (#ARY003C, R&amp;D Systems). Western blotting was used to investigate autophagic markers and protein kinase activity. Cell migration inhibition was determined by wound healing assay following treatment with a sublethal dose of PV-10 or pan-WNK inhibitor WNK463. Tumor xenograft studies were carried out according to established protocols. Results: Treatment with PV-10 leads to consistent inhibition of WNK lysine deficient protein kinase 1 (WNK1) phosphorylation based on protein kinase profiling of drug-treated cancer cells when compared with vehicle-treated cells. WNK1 has been implicated as an inhibitor of autophagy and a promoter of cell migration and invasion in several cancers. Western blot analysis showed that PV-10 leads to the downregulation of SQSTM1/p62, upregulation of Beclin-1, and conversion of LC3B-I into LC3B-II, indicating activation of autophagy. PV-10 was also found to significantly inhibit the migration of cancer cells similar to the inhibitor WNK463. Significant tumor regression and target modulation was noted in tumor-bearing animals treated with PV-10. Conclusion: In addition to the known activity of PV-10 to mediate tumor-specific immune responses and cytotoxic effects in neoplasms, we have identified novel therapeutic targets for PV-10, such as WNK1, and provide new insights into its effect on autophagy and metastasis. Our data provide essential mechanism-based evidence and biomarkers of activity to formulate effective PV-10 backbone clinical studies in the future. Citation Format: Son Tran, Satbir Thakur, Mohit Jain, Chunfen Zhang, Aru Narendran. Identification and in vivo validation of unique anti-oncogenic properties and mechanisms involving protein kinase signalling and autophagy mediated by the investigational new agent PV-10 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1121.

Abstract 5218: Oral beta-glucan enhanced anti-ganglioside antibody titer after vaccination against high-risk neuroblastoma: Results of a randomized trial

Abstract Background and Aim: Ganglioside GD2/GD3 vaccine stimulated robust antibody response among patients with high-risk metastatic neuroblastoma (HR-NB) who had prior disease progression (J Clin Oncol 39:215-226, 2020). High anti-GD2-IgG1antibody titer was associated with improved progression-free survival and overall survival in multivariable analyses. A gel formulation of yeast beta-glucan was used as an oral vaccine adjuvant, but its importance remained unproven. Patients and Methods: In a follow-up randomized Phase II trial (Clinicaltrials.gov identifier: NCT00911560), seven vaccine injections at 1, 2, 3, 8, 20, 32 and 52 weeks were administered to patients with HR-NB during their first or subsequent remissions. Each subcutaneous vaccine injection consisted of 30 ug each of GD2 and GD3, which was lactonized and conjugated to keyhole limpet hemocyanin and mixed with the subcutaneous saponin OPT-821 adjuvant at 150 µg/m2. No patients in this analysis received prior ganglioside vaccine. They were randomized to Arm 1 (n=54) receiving no glucan, or Arm 2 (n=53) receiving oral beta-glucan regimen (40 mg/kg/day, 14 days on/14 days off) starting at week 1. From week 6 onwards, all 107 patients received oral beta-glucan regimen through year end or up to disease progression. Serum IgG1 against GD2 and GD3, and IgM against GD2 were measured by ELISA at (right before) each vaccine injection. Wilcoxon rank sum test was used to compare antibody titers between the 2 arms. Results: In both arms, patients had comparable disease status at study entry, with 70% each in first remission. The remaining patients were in second remission after one prior disease progression. Consistently higher antibody response was observed among Arm 2 patients. The primary endpoint was met for anti-GD2-IgG1 titer at vaccine injection #6 at 32 weeks (p=0.08). Per protocol design, statistical significance (p&amp;lt;0.1) of anti-GD2-IgG1titer was observed at vaccine #5 (2.7-fold), #6 (1.4-fold), and #7 (4.1-fold), irrespective of being in first or second remission at study entry. Total anti-GD2-IgG1 antibody exposure (AUC) up to vaccine #7 for Arm 2 was 1.9-fold higher than that of Arm 1 (p=0.05). In contrast, anti-GD2-IgM achieved statistical significance only at vaccine #4 (p=0.001), and for anti-GD3-IgG1, only at vaccine #5 (p=0.07). Oral beta-glucan was well tolerated, and no patient showed pain or neuropathic side effects despite having higher antibody titers. Conclusion: Adding oral yeast beta-glucan as vaccine adjuvant during the first 6 weeks of immunization significantly enhanced the anti-GD2-IgG1 antibody response without added toxicities. Its impact on patient survival will require a longer clinical follow-up. Citation Format: Irene Y. Cheung, Audrey Mauguen, Yi Feng, Govind Ragupathi, Ellen Basu, Stephen S. Roberts, Shakeel Modak, Brian H. Kushner, Nai-Kong V. Cheung. Oral beta-glucan enhanced anti-ganglioside antibody titer after vaccination against high-risk neuroblastoma: Results of a randomized trial [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5218.

Advancing therapy for neuroblastoma.

Neuroblastomas are tumours of sympathetic origin, with a heterogeneous clinical course ranging from localized or spontaneously regressing to widely metastatic disease. Neuroblastomas recapitulate many of the features of sympathoadrenal development, which have been directly targeted to improve the survival outcomes in patients with high-risk disease. Over the past few decades, improvements in the 5-year survival of patients with metastatic neuroblastomas, from <20% to >50%, have resulted from clinical trials incorporating high-dose chemotherapy with autologous stem cell transplantation, differentiating agents and immunotherapy with anti-GD2 monoclonal antibodies. The next generation of trials are designed to improve the initial response rates in patients with high-risk neuroblastomas via the addition of immunotherapies, targeted therapies (such as ALK inhibitors) and radiopharmaceuticals to standard induction regimens. Other trials are focused on testing precision medicine strategies for patients with relapsed and/or refractory disease, enhancing the antitumour immune response and improving the effectiveness of maintenance regimens, in order to prolong disease remission. In this Review, we describe advances in delineating the pathogenesis of neuroblastoma and in identifying the drivers of high-risk disease. We then discuss how this knowledge has informed improvements in risk stratification, risk-adapted therapy and the development of novel therapies.

Quantifying intraventricular drug delivery utilizing programmable ventriculoperitoneal shunts as the intraventricular access device.

Programmable ventriculoperitoneal shunts (pVP shunts) are increasingly utilized for intraventricular chemotherapy, radioimmunotherapy, and/or cellular therapy. Shunt adjustments allow optimization of drug concentrations in the thecal space with minimization in the peritoneum. This report assesses the success of the pVP shunt as an access device for intraventricular therapies. Quantifying intrathecal drug delivery using scintigraphy by pVP shunt model has not been previously reported. We performed a single-institution, retrospective analysis on patients with CNS tumors and pVP shunts from 2003 to 2020, noting shunt model. pVP flow was evaluated for consideration of compartmental radioimmunotherapy (cRIT) using In-111-DTPA scintigraphy. Scintigraphy studies at 2-4h and at 24h quantified ventricular-thecal and peritoneal drug activity. Twenty-two CSF flow studies were administered to 15 patients (N = 15) with diagnoses including medulloblastoma, metastatic neuroblastoma, pineoblastoma, and choroid plexus carcinoma. Six different types of pVP models were noted. 100% of the studies demonstrated ventriculo-thecal drug activity. 27% (6 of 22) of the studies had no peritoneal uptake visible by imaging. 73% (16 of 22) of the studies had minimal relative peritoneal uptake (< 12%). 27% (6 of 22) of the studies demonstrated moderate relative peritoneal uptake (12-37%). No studies demonstrated peritoneal uptake above 37%. All patients had successful drug delivery of In-111-DTPA to the ventriculo-thecal space. 73% of the patients had minimal relative (< 12%) peritoneal drug uptake. Though efficacy varies by shunt model, low numbers preclude conclusions regarding model superiority. CSF flow scintigraphy studies assesses drug distribution of In-111-DTPA, informing CSF flow for delivery of intraventricular therapies.

Imaging Findings of Pediatric Orbital Masses and Tumor Mimics.

Pediatric orbital masses are not common but encompass a wide spectrum of benign and malignant entities that range from developmental anomalies to primary and secondary orbital malignancies and metastatic disease. Certain orbital tumors are unique to pediatric patients, such as retinoblastoma and neuroblastoma. Clinical symptoms and signs are often insufficient to differentiate between orbital lesions, and imaging is essential for narrowing the diagnostic considerations and determining the most appropriate management strategy. MRI is the primary imaging modality for evaluating orbital masses in children, with US and CT playing complementary roles. The authors review a spectrum of masses and tumor mimics that affect the pediatric globe and orbit. The shared and differentiating characteristics of pediatric orbital lesions are reviewed. Emphasis is placed on utilizing an orbital compartment-based approach to narrow the differential diagnosis. By using this organizational scheme, the authors describe intraocular processes (retinoblastoma, persistent fetal vasculature, and Coats disease), intraconal lesions (lymphatic malformation, schwannoma, optic nerve sheath meningioma, and optic pathway glioma), extraconal lesions (infantile hemangioma, rhabdomyosarcoma, idiopathic orbital inflammation, lymphoma, venous varix, plexiform neurofibroma, and pleomorphic adenoma of the lacrimal gland), and lesions involving the bony orbit (dermoid cyst, metastatic neuroblastoma, and Langerhans cell histiocytosis). The authors describe the basic management of each entity. Orbital infections and traumatic lesions are beyond the scope of this article. ©RSNA, 2022.

Highlights from Recent Cancer Literature

Highlights from Recent Cancer Literature