High-risk Neuroblastoma Research Articles

Prognostic factors for intermediate- or high-risk neuroblastomas in children in China

BackgroundEvidence regarding the characteristics and prognosis of neuroblastoma (NBL) in China is limited. We aimed to investigate the characteristics and prognosis of intermediate- or high-risk NBL in children in China.MethodsWe included 147 patients with intermediate- or high-risk NBL evaluated from January 2006 to March 2015. The patients were aged 1 month to 15.5 years, 66% of them were boys, and 117 (79.6%) were diagnosed with high-risk NBL.ResultsAfter a median follow-up of 32.5 months, 80 (45.6%) patients survived, with a median survival time of 48 months (95% confidence interval [CI]: 36.41–59.59). High-risk patients (hazard ratio [HR]: 12.467; 95% CI: 11.029–12.951), partial response (PR) (HR: 1.200; 95% CI: 1.475–2.509) or progression disease (PD) (HR: 1.924; 95% CI: 1.623–3.012) after induction chemotherapy, and intracranial metastasis (HR: 3.057; 95% CI: 0.941–4.892) were independent risk factors for survival (p < 0.05) and postrelapse survival (p < 0.05). NBL relapse, male sex, and PR or PD after induction chemotherapy were risk factors for event-free survival (p < 0.05).ConclusionsIn addition to previously established independent risk factors, such as age, risk group, and relapse, efficacy of induction chemotherapy and intracranial metastasis play significant roles in the prognosis of NBL.

Abstract C159: ALK signaling primes the DNA damage response allowing exploitation of ATR inhibition in ALK-driven Neuroblastoma

Abstract High-risk neuroblastoma currently presents significant clinical challenges. Oncogenes such as MYCN and ALK, which are often involved in high-risk neuroblastoma, result in increased replication stress in cancer cells, offering therapeutically exploitable options. We previously identified an ATR/ALK inhibitor combination as an effective therapeutic approach in two independent genetically modified mouse neuroblastoma models. Here we show that ALK signaling leads to phosphorylation of ATR and CHK1, supporting an effective DNA damage response. Remarkably, the importance of ALK inhibition is supported by mouse data, in which ATRi monotreatment resulted in a robust initial response, but subsequent relapse, in contrast to ALKi/ATRi combination treatment that resulted in robust and sustained responses. Here, we describe the mechanism underlying the remarkable tumor response to combined ATR/ALK inhibition. Our results identify a unique ability of ATR inhibition to trigger tumor regression in neuroblastoma and underscore the importance of further exploring combined ALK/ATR inhibition in neuroblastoma, particularly in high-risk patient groups with oncogene-induced replication stress. Citation Format: Marcus Borenäs, Ganesh Umapathy, Dan E. Lind, Wei-Yun Lai, Jikui Guan, Joel Johansson, Eva Jennische, Alexander Schmidt, Jonatan Gabre, Mats Bemark, Michael N. Hall, Jimmy Van den Eynden, Bengt Hallberg, Ruth H. Palmer. ALK signaling primes the DNA damage response allowing exploitation of ATR inhibition in ALK-driven Neuroblastoma [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2023 Oct 11-15; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2023;22(12 Suppl):Abstract nr C159.

129P Naxitamab efficacy in patients with refractory/relapsed high-risk neuroblastoma and bone metastases as assessed by Curie score

129P Naxitamab efficacy in patients with refractory/relapsed high-risk neuroblastoma and bone metastases as assessed by Curie score

Abstract LB_C20: A tumor-associated chemokine attracts CCR4-expressing CD4+ cells to foster immune repression and tumor aggressiveness in MYCN-driven neuroblastoma

Abstract Neuroblastoma, especially those with aberrant MYCN activation, often harbor an immunosuppressive microenvironment to fuel malignant growth and trigger treatment resistance. Despite this knowledge, there are no effective strategies to tackle this problem. Here we combined analyses of human neuroblastoma with live tracking and functional studies of the tumor microenvironment (TME) in zebrafish. We identified a tumor-associated chemokine (TAC) as a key driver of MYCN-mediated immunosuppression and neuroblastoma aggression. Taking advantage of in vivo zebrafish models of MYCN-driven neuroblastoma that resemble human high-risk disease, we demonstrated that TAC overexpression in zebrafish neural crest cells induces an immunosuppressive TME while promoting rapid tumor onset and progression. We also demonstrated that as early as the premalignant stage, tumor cells secrete TAC to attract CCR4-expressing Cd4+ cells to induce immunosuppression and tumor aggression. In addition, genetically depleting Cd4+ T regulatory cells abolishes the immunorestrictive and pro-tumorigenic effects of TAC. We showed that human MYCN-activated neuroblastoma upregulates and secretes TAC, which is a reliable predictor of poor patient survival. Analysis of primary patient samples demonstrates a strong positive association between MYCN and TAC expression in neuroblastoma cells together with the enrichment of FOXP3+ T cells in the TME. Our work provides the first example that MYCN can activate TAC to allure CD4+ immune cells to the TME and incite immunosuppression, positioning TAC as a potential novel immunotherapeutic target for the treatment of MYCN-driven high-risk neuroblastoma. Citation Format: Xiaodan Qin, Andrew Lam, Xu Zhang, Satyaki Sengupta, J. Bryan Iorgulescu, Sanjukta Das, Zhenwei Zhou, Tao Zuo, Grace K. Meara, Madison Rager, Alexander E. Floru, Hongru Ni, Chinyere Kemet, Divya Veerapaneni, Daniel Kashy, Liang Lin, Kenneth Lloyd, Lauren Kwok, Kaylee S. Smith, Raghavendar T. Nagaraju, Rob Meijers, Craig Ceol, Ching-Ti Liu, Sanda Alexandrescu, Catherine J. Wu, Derin B. Keskin, Rani E. George, Hui Feng. A tumor-associated chemokine attracts CCR4-expressing CD4+ cells to foster immune repression and tumor aggressiveness in MYCN-driven neuroblastoma [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2023 Oct 11-15; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2023;22(12 Suppl):Abstract nr LB_C20.

PD-L1-expressing natural killer cells predict favorable prognosis and response to PD-1/PD-L1 blockade in neuroblastoma

ABSTRACT T/NK cell-based immunotherapy has achieved remarkable success in adult cancers but has limited efficacy in pediatric malignancies including high-risk neuroblastoma (NB). Immune defects of NB tumor microenvironment are poorly understood compared with adults. Here, we described the unique characteristics of NB immune contexture and determined the phenotype signatures of PD-L1-expressing CD8+ T and NK cells in NB tumors by systemically analyzing the spatial distribution of T and NK cells and the distinct expression of programmed death 1 (PD-1) and its ligand (PD-L1) in patients with NB. We found that PD-L1-expressing CD8+ T and NK cells in NB tumors were highly activated and functionally competent and associated with better clinical outcomes. Intratumoral NK cells were a favorable prognostic biomarker independent of CD8+ T cells, PD-1/PD-L1 expression, tumor stage, MYCN amplification, and risk classification. NK cells combined with anti-PD-1/PD-L1 antibodies showed potent antitumor activity against both MYCN-amplified and non-amplified NBs in vitro and in vivo, and PD-L1-expressing NK cells associated with improved antitumor efficacy. Collectively, we raise novel insights into the role of PD-L1 expression on CD8+ T-cell and NK-cell activation. We highlight the great potential of intratumoral NK cells in better defining risk stratification, and predicting survival and response to anti-PD-1/PD-L1 therapy in NB. These findings explain why single anti-PD-1/PD-L1 therapy may not be successful in NB, suggesting its combination with NK cell-adoptive cellular therapy as a promising strategy for relapsing/refractory NB. This study provides a potential prospect that patients with PD-L1-expressing NK cells may respond to anti-PD-1/PD-L1 therapy.

Abstract B110: β3-adrenergic receptor as a new molecular target in neuroblastoma treatment

Abstract Purpose of study: β3-Adrenergic receptor correlation with tumor growth and progression in preclinical and clinical studies in neuroblastoma. Experimental procedures: Knock-out of β3-Adrenergic Receptor (β3-AR) in Neuroblastoma (NB) cell lines using CRISPR-Cas9 technology. In vivo experiment using β3-AR knock-out cells in order to evaluate the tumor growth in mice. RNA Sequencing of tumor masses derived from mice to investigate β3-AR Dependent tumor signaling pathways. Flow Cytometry analysis to observe the expression level of β3- Adrenergic Receptor on circulating tumor cells (CTCs) in peripheral blood and on disseminated tumor cells (DTCs) in bone marrow from NB patients with low-risk and high-risk prognosis. Summary of data: CRISPR/Cas9 technology was performed to obtain ADRB3-/- clones from human and murine NB cell lines. ADRB3-/- knocked-out cells were inoculated in murine models NU-Foxn1nu and A/J mice, showing an absence of tumor growth compared to wild type NB cells. Subsequently, RNA sequencing on tumor masses was performed to investigate β3-AR-dependent tumor signaling pathways. RNA-sequencing analysis showed many pathways were altered. Notably, downregulation of genes involved in epithelial–mesenchymal transition (EMT) pathway and genes involved in cell adhesion were underlined in Knock-out vs control, correlated with the absence of tumor growth. Cytofluorimetric analysis of β3-AR level expression were conducted on circulating tumor cells (CTCs) in peripheral blood and on disseminated tumor cells (DTCs) in bone marrow from NB patients with low-risk and high-risk prognosis to evaluating the expression levels of β3-AR. As expected, most of the high-risk NB patients showed high percentage of β3-AR+ cells among CTCs and DTCs, while the majority of low-risk patients showed lower percentage. Statement of the conclusions: Ours data showed that β3-AR could be a potential target therapy for neuroblastoma treatment. In fact, his deletion results in an absence of tumor growth and progression as demonstrate in mice in vivo experiments. In addition, NB patients with lower β3-AR level, showed a better prognosis . Furter studies should be focused on the pathways related to β3-AR. Moreover, new drugs will be tested in order to normalize the level of β3-AR in NB patients. Citation Format: Rossana Putino, Alessia Boaretto, Gennaro Bruno, Gianluca Mattei, Annalisa Tondo, Claudio Favre, Maura Calvani. β3-adrenergic receptor as a new molecular target in neuroblastoma treatment [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2023 Oct 11-15; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2023;22(12 Suppl):Abstract nr B110.

Extremely high prognostic risk group of neuroblastic tumors: histological, immunophenotypic and genetic characteristics. Literature review and own observations

Clinical heterogeneity appears to be one of the most characteristic feature of the group of peripheral neuroblastic tumors, ranging from spontaneous tumor regression to a widespread process, often resistant to multimodal therapeutic strategies. Despite significant progress in treatment, about 40 % of patients with high-risk neuroblastoma die from disease recurrence after complete response to first-line therapy. These 40 % are considered a “extremely high” risk group requiring intensification of therapeutic regimens from the time of diagnosis. Histological and molecular predictive features of this group are of high scientific and practical interest for the correct therapy.

Renal preservation in high-risk retroperitoneal neuroblastoma: Impact on survival and local progression

BackgroundRetroperitoneal neuroblastomas predominantly encroach upon critical structures, complicating surgical intervention and yielding elevated rates of surgery-associated complications. The kidney and renal vasculature represent the organs most susceptible to retroperitoneal neuroblastoma infiltration. Prior investigations have revealed high nephrectomy incidence and a paucity of renal-preserving surgical approaches. MethodsA retrospective analysis was undertaken, examining patients with retroperitoneal neuroblastoma who underwent surgical procedures from January 2018 to December 2019 at Beijing Children's Hospital. ResultsThe study encompassed 225 patients, presenting a median age of 37 months. Concomitant nephrectomy and tumor excision were performed in 11 (4.9%) patients, while 214 (95.1%) patients successfully preserved their kidneys during surgery. Among the patients who retained their kidneys, 8 (3.5%) experienced renal atrophy postoperatively. Predominant rationales for simultaneous nephrectomy included tumor invasion into the renal hilum (n = 9), markedly diminished function of the affected kidney (n = 2), and ureteral infiltration (n = 1). Subsequent to a median follow-up duration of 43 months, the outcomes demonstrated no considerable divergence in overall survival (OS) and event-free survival (EFS) between the nephrectomy and renal-preserving cohorts among high-risk (HR) neuroblastoma patients. Among the eight HR children who underwent nephrectomy, four experienced local recurrence. The nephrectomy cohort exhibited a significantly elevated cumulative incidence of local progression (CILP) relative to the renal-preserving group. ConclusionIn high-risk retroperitoneal neuroblastoma patients, nephrectomy does not enhance CILP, EFS, or OS. The guiding surgical tenet involves preserving the kidney while striving for gross total resection of the primary neoplasm, barring instances of severe deterioration of the affected renal function.

Prevention of STAT3-related pathway in SK-N-SH cells by natural product astaxanthin

PurposeNeuroblastoma (NB) is the most common solid malignancy in children. Despite current intensive treatment, the long-term event-free survival rate is less than 50% in these patients. Thus, patients with NB urgently need more valid treatment strategies. Previous research has shown that STAT3 may be an effective target in high-risk NB patients. However, there are no effective inhibitors in clinical evaluation with low toxicity and few side effects. Astaxanthin is a safe and natural anticancer product. In this study, we investigated whether astaxanthin could exert antitumor effects in the SK-N-SH neuroblastoma cancer cell line.MethodMTT and colony formation assays were used to determine the effect of astaxanthin on the proliferation and colony formation of SK-N-SH cells. Flow cytometry assays were used to detect the apoptosis of SK-N-SH cells. The migration and invasion ability of SK-N-SH cells were detected by migration and invasion assays. Western blot and RT-PCR were used to detect the protein and mRNA levels. Animal experiments were carried out and cell apoptosis in tissues were assessed using a TUNEL assay.ResultWe confirmed that astaxanthin repressed proliferation, clone formation ability, migration and invasion and induced apoptosis in SK-N-SH cells through the STAT3 pathway. Furthermore, the highest inhibitory effect was observed when astaxanthin was combined with si-STAT3. The reason for this may be that the combination of astaxanthin and si-STAT3 can lower STAT3 expression further than astaxanthin or si-STAT3 alone.ConclusionAstaxanthin can exert anti-tumor effect on SK-N-SH cells. The inhibitory effect was the higher when astaxanthin was combined with si-STAT3.

Predictive value of 2-deoxy-2-fluorine-18-fluoro-D-glucose positron emission tomography/computed tomography parameters for MYCN amplification in high-risk neuroblastoma

ObjectivesTo investigate the predictive value of 2-deoxy-2-fluorine-18-fluoro-D-glucose positron emission tomography/computed tomography (18F-FDG PET/CT) parameters for MYCN amplification in high-risk neuroblastoma (HR-NB). Materials and methodsA retrospective analysis was performed by reviewing 68 HR-NB patients who underwent MYCN testing and 18F-FDG PET/CT imaging at our hospital between January 2018 and December 2019. Based on the results of MYCN testing, patients were categorized into either the MYCN-amplified (MNA) or MYCN non-amplified (MYCN-NA) group. The 18F-FDG PET/CT parameters, including maximum standardized uptake value (SUVmax), mean standardized uptake value (SUVmean), peak standardized uptake value (SUVpeak), tumor metabolic volume (MTV), total lesion glycolysis (TLG), coefficient of variation (COV), and areas under the curve of cumulative SUV-volume histogram index (AUC-CSH index) were evaluated. Independent predictors were identified through univariate and multivariate logistic regression analyses, and their diagnostic performance was evaluated using the receiver-operating characteristic (ROC) curve. ResultsUnivariate logistic regression analysis revealed that SUVpeak was significantly associated with MYCN amplification. Multivariate logistic regression analysis showed that SUVpeak was an independent predictor of MYCN amplification in HR-NB [Odds ratio (OR) = 0.673, 95 % confidence interval (95 % CI): 0.494–0.917, P = 0.012]. ROC curve analysis demonstrated that the predictive model including SUVpeak had higher diagnostic performance [area under the curve (AUC): 0.790, 95 % CI: 0.677–0.881, sensitivity: 0.861, specificity: 0.591, positive predictive value (PPV): 0.820, negative predictive value (NPV): 0.722] compared to using SUVpeak alone (AUC: 0.640, 95 % CI: 0.514–0.752, sensitivity: 0.630, specificity: 0.682, PPV: 0.806, NPV: 0.469). ConclusionSUVpeak can predict the MYCN amplification in HR-NB patients. The predictive model constructed by combining SUVpeak and age can distinguish MYCN status in HR-NB non-invasively with superior efficacy compared to using SUVpeak alone.

The Non-Hematopoietic Content in Paediatric Autologous Hematopoietic Stem Cell Grafts Is Skewed Towards Regulatory Myeloid and Exhausted Phenotypes

Autologous hematopoietic stem cell transplant (aHSCT) is a central component of paediatric brain tumours and high-risk neuroblastoma management. Standardly, chemotherapy and G-CSF are used to mobilize the CD34+ hematopoietic stem/progenitor cells (HSC), which are used to support hematopoietic recovery following dose chemotherapy. Clinically, the graft infused is defined by solely by the CD34+ content. The non-hematopoietic passenger cells makeup most of the graft and are a mixture of myeloid and lymphoid cells that are potentially biologically active in the post-transplant setting. Here we study the content of the graft, focusing on the phenotypes of the cell populations, to begin to look at how the non-hematopoietic cells may facilitate anti-tumor activity, affect the tumour microenvironment, and/or immune recovery post-transplant. High parameter mass cytometry, with a custom 40-marker panel, was used to characterize 43 autologous cryopreserved grafts from children (median age 39 months, range 14-255 months) undergoing apheresis following chemotherapy and G-CSF mobilization. Healthy G-CSF-mobilized allogeneic donors (allograft) were used as a comparator group (n=10). Young children frequently have robust mobilization (peripheral blood CD34 count range from 100-1800 CD34/µL on day of collection) and generally one day collection will support multiple cycles of high dose therapy (target collections 20 x10 6 CD34+ cells/kg and often over collecting in 2-3 blood volume processed). This results in a product that is rich in CD34+ cells, with intergraft heterogeneity (median 7%; range 0.7-31%), compared to the CD34+ content of allografts (median 1.1%; range 0.3-2.4%) (autograft vs allograft median CD34 difference p&amp;lt;0.00005; Wilcoxon unpaired). There was variability in the non-hematopoietic component in the autografts (median T cells 10.8%; range 0.6 - 51.7%, and median monocytes 18.8%; range 4.1 - 51.4%). The allogeneic products were found to have less variability (T cells: 19.9 - 56%; monocytes: 7.3 - 19.6%). Autografts had increased expression of T cell exhaustion markers, with a median 30.8% (range 14.7 - 88.1%) of T cells expressing TIGIT and 35.1% (range 13.1 - 75.9%) expressing PD1 compared to the allografts (median TIGIT: 15.7%; range 9.3 - 28.7% and median PD1: 11%; range 4.2 - 19.7%). When grafts from high mobilizers (N= 21; &amp;gt;7% CD34+ cells) were analyzed by the actual number of cells infused they had had fewer regulatory cells: monocytic-myeloid derived-suppressor cells (M-MDSCs) (3.6x10 7 cells/kg; range 0.5 - 73.8x10 7; p&amp;lt; 0.0003), non-classical monocytes (0.9x10 7 cells/kg; range 0.5 - 21.3x10 7 cells/kg; p&amp;lt; 0.002) compared to the grafts from lower mobilizers (N = 22; &amp;lt;7.1% CD34+ cells) M-MDSC: median 7.7x10 7/kg; range 0.6 - 21.3x10 7 cells/kg, non-classical monocytes: 1.7x10 7 cells/kg; range 0.05 - 3.7x10 7 cells/kg). T cells and NK cells did not differ between high and low mobilizers. We are seeing significant differences in the regulatory cell populations infused in paediatric aHSCT based on the how robustly a patient mobilizes CD34+ cells after chemotherapy and G-CSF. It is not known whether these differences are clinically significant or affect anti-tumour immunity, tumour microenvironment perturbation, or immune recovery. With this high parameter mass cytometry strategy, we will be able to correlate engraftment kinetics and transplant outcomes (survival, relapse), which will allow us to re-envision how grafts should be optimally manufactured. Controllable variables include the timing of collection (earlier or later in the clinical course), alternative growth factor usage, enrichment or depletion of cell populations in the graft, or post-transplant growth factor administration. We suggest that the aHSCT graft can be thought of as an immunotherapy tool and not just for hematopoietic recovery.

Targeted Degradation of XIAP is Sufficient and Specific to Induce Apoptosis in MYCN-overexpressing High-risk Neuroblastoma.

XIAP degradation is sufficient to kill MYCN-amplified neuroblastoma which overexpresses and relies on XIAP as a brake against cell death, without affecting normal cells.

Integrated re-analysis of transcriptomic and proteomic datasets reveals potential mechanisms for Zika viral-based oncolytic therapy in neuroblastoma

Background Paediatric neuroblastoma and brain tumours account for a third of all childhood cancer-related mortality. High-risk neuroblastoma is highly aggressive and survival is poor despite intensive multi-modal therapies with significant toxicity. Novel therapies are desperately needed. The Zika virus (ZIKV) can access the nervous system and there is growing interest in employing ZIKV as a potential therapy against paediatric nervous system tumours, including neuroblastoma. Methods Here, we perform extensive data mining, integration and re-analysis of ZIKV infection datasets to highlight molecular mechanisms that may govern the oncolytic response in neuroblastoma cells. We collate infection data of multiple neuroblastoma cell lines by different ZIKV strains from a body of published literature to inform the susceptibility of neuroblastoma to the ZIKV oncolytic response. Integrating published transcriptomics, interaction proteomics, dependency factor and compound datasets we propose the involvement of multiple host systems during ZIKV infection. Results Through data mining of published literature, we observed most paediatric neuroblastoma cell lines to be highly susceptible to ZIKV infection and propose the PRVABC59 ZIKV strain to be the most promising candidate for neuroblastoma oncolytic virotherapy. ZIKV induces TNF signalling, lipid metabolism, the Unfolded Protein Response (UPR), and downregulates cell cycle and DNA replication processes. ZIKV infection is dependent on sterol regulatory element binding protein (SREBP)-regulated lipid metabolism and three protein complexes; V-ATPase, ER Membrane Protein Complex (EMC) and mammalian translocon. We propose ZIKV non-structural protein 4B (NS4B) as a likely mediator of ZIKVs interaction with IRE1-mediated UPR, lipid metabolism and mammalian translocon. Conclusions Our work provides a significant understanding of ZIKV infection in neuroblastoma cells, which will facilitate the progression of ZIKV-based oncolytic virotherapy through pre-clinical research and clinical trials.

A CRISPR-drug perturbational map for identifying compounds to combine with commonly used chemotherapeutics

Combination chemotherapy is crucial for successfully treating cancer. However, the enormous number of possible drug combinations means discovering safe and effective combinations remains a significant challenge. To improve this process, we conduct large-scale targeted CRISPR knockout screens in drug-treated cells, creating a genetic map of druggable genes that sensitize cells to commonly used chemotherapeutics. We prioritize neuroblastoma, the most common extracranial pediatric solid tumor, where ~50% of high-risk patients do not survive. Our screen examines all druggable gene knockouts in 18 cell lines (10 neuroblastoma, 8 others) treated with 8 widely used drugs, resulting in 94,320 unique combination-cell line perturbations, which is comparable to the largest existing drug combination screens. Using dense drug-drug rescreening, we find that the top CRISPR-nominated drug combinations are more synergistic than standard-of-care combinations, suggesting existing combinations could be improved. As proof of principle, we discover that inhibition of PRKDC, a component of the non-homologous end-joining pathway, sensitizes high-risk neuroblastoma cells to the standard-of-care drug doxorubicin in vitro and in vivo using patient-derived xenograft (PDX) models. Our findings provide a valuable resource and demonstrate the feasibility of using targeted CRISPR knockout to discover combinations with common chemotherapeutics, a methodology with application across all cancers.

CNSC-35. EVALUATING THE THERAPEUTIC POTENTIAL OF NOVEL NTRK AGONISTS AND ANTAGONISTS IN HIGH-RISK NEUROBLASTOMA

Abstract Neuroblastoma is the most common extra-cranial tumor diagnosed in children within the first two years of their lives. Although low-risk and intermediate -risk neuroblastoma patients have a survival rate of 90-95%, high-risk neuroblastoma patients have a survival rate of approximately 50%. To improve the survival rate in high-risk patients, our group focuses on tropomyosin receptor kinases (TRKs), which are family of tyrosine kinases that have been heavily implicated in crucial developmental processes, such as differentiation, that are typically hijacked in cancer. Using de novo agonists specifically designed against three different neurotrophin receptors (TrkA, TrkB, TrkC), our group is investigating the fundamental biological role of TRK receptors in mediating tumorigenesis in neuroblastoma. Preliminary results show that our TrkA agonist not only increase both ERK and AKT activity but also causes a significant decrease in TrkA expression in several neuroblastoma cell lines which we hypothesize is due to constitutive activation of TrkA, leading to its internalization and degradation. Phenotypically, we observe that neuroblastoma cell line SK-N-SY5Y, which is typically used in differentiation studies, lose their neuroblast-like phenotype when treated with TrkA agonist, and begin to exhibit neurite outgrowth which may be indicative of differentiation-associated pathways being activated due to TrkA activation. Using a combination of de novo protein design, immunoblotting, RNA-sequencing, and in vivo studies to characterize the effect(s) TRK agonists have on neuroblastoma, we hope to assess whether targeting and modifying the activity of TrkA, and other Trk receptors such as TrkB and TrkC, holds new therapeutic promise for patients with high-risk neuroblastoma.

S-100 and MATH-1 Protein Expressions Can Be Useful for the Prediction of Clinical Outcome in Neuroblastoma Patients.

Neuroblastoma (NB) is the most frequent extracranial solid tumor of childhood, remarkable for its broad spectrum of clinical behavior. This diversity in behavior correlates closely with defined clinical and biological features and combinations of prognostic variables are used for risk-group assignment. S-100 proteins have roles in differentiation and were shown to be frequently dysregulated in NB. MATH-1 protein plays role in neuronal cell differentiation through development. However, up to date, there are no studies evaluating the relationship between MATH-1 and NB. Grb2-associated binding (Gab) proteins have roles in the regulation of cell growth and differentiation. Gab1 was reported to be related to poor survival of high-risk NB patients. The aim of this study was to investigate the relationship between differentiation-related S-100, MATH-1, and Gab1 proteins and risk group and/or stages of NB. A significant relation was found between S-100 and early stages of NB. This study also revealed a significant association between MATH-1 and low-risk groups. S-100 and MATH-1 were also shown to provide survival advantages among stages and risk groups. The findings of this study support the assumption that S-100 and MATH-1 can be potential prognostic biomarkers for staging and risk-group assignment of NB patients. These proteins can be useful tools for clinicians to guide through treatment options, especially for the evaluation of tumor differentiation.

New Treatments, New Challenges: Nephrotoxicity-Associated Naxitamab in Pediatric Patients with High-Risk Neuroblastoma

New Treatments, New Challenges: Nephrotoxicity-Associated Naxitamab in Pediatric Patients with High-Risk Neuroblastoma

Reduced Anticancer Potency of Carboplatin in the Presence of Sialic Acid in SH-SY5Y Cells

Background: Neuroblastoma (NB) is the most common solid childhood tumor with aggressive behavior and a high mortality rate. Multiple therapeutic approaches have been developed and applied to treat neuroblastoma, but resistance to therapies is inevitable, leading to treatment failure and cancer relapse. Therefore, perceiving the mechanisms of reduced drug sensitivity seems appropriate and promising in NB treatment to determine synergistic effects strategies like combination therapy. Objectives: The present study aimed to investigate the modulation effect of the therapeutic efficacy of carboplatin (a chemotherapeutic agent) by co-administration of sialic acid (an alpha-keto acid sugar with a 9-carbon backbone located at the outermost end of N-linked and O-linked carbohydrate chains and in lipid-associated glycoconjugates showing aberrant expression in tumor cells caused tumor-genesis) in NB cells. Methods: In the present study, the effects of sialic acid, carboplatin, and Sia-Carbo (sialic acid in combination with carboplatin) were evaluated on viability and apoptosis using the determination of EC50 and IC50. Also, the capability of metastasis and apoptosis were assessed using real-time PCR. Moreover, the expression of MRP-1 encoded by ABCC1 (as a target for therapeutic suppression in high-risk neuroblastoma) was studied in different treatment groups. Conclusions: Regarding IC50 increasing carboplatin in the presence of sialic acid, the results showed that sialic acid treatment significantly modulated carboplatin's effect on cell apoptosis and induced ABCC1 expression. These findings show that sialic acid metabolic engineering can be a good approach to neuroblastoma therapy. It was suggested that targeting aberrant sialylation in combination with carboplatin exerts more profound apoptotic and anticancer effects on the neuroblastoma SH-SY5Y cell line than carboplatin monotherapy.

Successful Transjugular Portosystemic Shunt Treatment of Pediatric Sinusoidal Obstruction: Case Report and Review of Literature.

In adults with medically refractory sinusoidal obstruction syndrome (SOS), a transjugular intrahepatic portosystemic shunt (TIPS) has been used successfully to improve portal hypertension and symptoms such as ascites. There is limited data on the use of TIPS for SOS in pediatric patients. The index case was reviewed retrospectively. PubMed and Medline databases were searched to identify other cases. A 4-year-old male with high-risk neuroblastoma, developed SOS after tandem autologous stem cell transplant. He was medically managed with defibrotide, diuretics, and peritoneal drainage, but, due to refractoriness, he underwent TIPS day +54 following bone marrow transplant. Hepatic venous pressure gradient improved from 17 to 8 mm Hg following TIPS placement with significant improvement in the patient's clinical status and ascites. However, 15 months later, his shunt remained patent, and he remains clinically well with stable liver enzymes. A literature review identified 13 pediatric cases of TIPS for SOS due to varied causes. TIPS caused a median hepatic venous pressure gradient of 9 mmHg (range, 2-38 mm Hg). The mortality following the procedure was 15%, with 2 cases who died at 2- and 11-days post-TIPS. At the time of the last follow-up (range 8-25 months), 5 patients were alive, and 8 were lost to follow-up. We present here a pediatric case of SOS due to stem cell transplant treated successfully with TIPS with a review of the literature. A timely, individualized application of TIPS can be effective in treating children with medication-refractory SOS.

Evaluation of anticancerogenic effect of flavonoid rich Verbascum gypsicola Vural &amp; Aydoğdu methanolic extract against SH-SY5Y cell line

Neuroblastoma (NB) is an embryonal neoplasm affecting the autonomic branch of the nervous system; it is the most commonly detected cancer type in children. NBs affecting children mostly present with metastatic disease that is hardly treatable with intensive multimodal therapy and portends a poor prognosis. Therefore, the likelihood of children with high-risk NB relapse remains extremely high, which calls for urgent action to discover novel treatment options to improve survival. Assessing the anti-cancer properties of known natural compounds may offer novel therapeutic options against NB. In this study we aimed to investigate the anti-cancer properties of the Verbacum gypsicola methanol extract (VGME) rich in flavonoids on SH-SY5Y cell line. For this purpose, we used LC-MS analysis to investigate the flavonoid composition of VGME, MTT analysis to investigate its effect on cell viability, and flow cytometry and qRT-PCR analyses to investigate its effect on apoptosis. VGME had a high flavonoid content. Its IC50 dose was 50 μg/mL at 48 hours. It significantly increased intracellular ROS level, apoptotic cells’ percentage, and mitochondrial disruption. The capacity of VGME to block cancer growth via an intrinsic apoptotic route implies that it might be a classic option for anticancer drug creation.