Neuroblastoma: An Updated Review on Biology and Treatment

Development of red blood cell-derived extracellular particles as a biocompatible nanocarrier of microRNA-204 (REP-204) to harness anti-neuroblastoma effect

Neuroblastoma (NB) is the most common extracranial solid tumor in the pediatric population with a high degree of heterogeneity in clinical outcomes. Upregulation of the tumor suppressor miR-204 in neuroblastoma is associated with good prognosis. Although miR-204 has been recognized as a potential therapeutic candidate, its delivery is unavailable. We hypothesized that REP-204, the red blood cell-derived extracellular particles (REP) with miR-204 loading, can suppress neuroblastoma cells in vitro. After miR-204 loading by electroporation, REP-204, but not REP carriers, inhibited the viability, migration, and 3D spheroid growth of neuroblastoma cells regardless of MYCN amplification status. SWATH-proteomics revealed that REP-204 treatment may trigger a negative regulation of mRNA splicing by the spliceosome, suppression of amino acid metabolism and protein production, and prevent SLIT/ROBO signaling-mediated cell migration, to halt neuroblastoma tumor growth and metastasis. The therapeutic efficacy of REP-204 should be further investigated in preclinical models and clinical studies.

The TERT Promoter is Polycomb-Repressed in Neuroblastoma Cells with Long Telomeres

Acquiring a telomere maintenance mechanism is a hallmark of high-risk neuroblastoma and commonly occurs by expressing telomerase (TERT). Telomerase-negative neuroblastoma has long telomeres and utilizes the telomerase-independent alternative lengthening of telomeres (ALT) mechanism. Conversely, no discernable telomere maintenance mechanism is detected in a fraction of neuroblastoma with long telomeres. Here, we show, unlike most cancers, DNA of the TERT promoter is broadly hypomethylated in neuroblastoma. In telomerase-positive neuroblastoma cells, the hypomethylated DNA promoter is approximately 1.5 kb. The TERT locus shows active chromatin marks with low enrichment for the repressive mark, H3K27me3. MYCN, a commonly amplified oncogene in neuroblstoma, binds to the promoter and induces TERT expression. Strikingly, in neuroblastoma with long telomeres, the hypomethylated region spans the entire TERT locus, including multiple nearby genes with enrichment for the repressive H3K27me3 chromatin mark. Furthermore, subtelomeric regions showed enrichment of repressive chromatin marks in neuroblastomas with long telomeres relative to those with short telomeres. These repressive marks were even more evident at the genic loci, suggesting a telomere position effect (TPE). Inhibiting H3K27 methylation by three different EZH2 inhibitors induced the expression of TERT in cell lines with long telomeres and H3K27me3 marks in the promoter region. EZH2 inhibition facilitated MYCN binding to the TERT promoter in neuroblastoma cells with long telomeres. Taken together, these data suggest that epigenetic regulation of TERT expression differs in neuroblastoma depending on the telomere maintenance status, and H3K27 methylation is important in repressing TERT expression in neuroblastoma with long telomeres.

SIGNIFICANCE

The epigenetic landscape of the TERT locus is unique in neuroblastoma. The DNA at the TERT locus, unlike other cancer cells and similar to normal cells, are hypomethylated in telomerase-positive neuroblastoma cells. The TERT locus is repressed by polycomb repressive complex-2 complex in neuroblastoma cells that have long telomeres and do not express TERT. Long telomeres in neuroblastoma cells are also associated with repressive chromatin states at the chromosomal termini, suggesting TPE.

Exploring the in vitro potential of royal jelly against glioblastoma and neuroblastoma: impact on cell proliferation, apoptosis, cell cycle, and the biomolecular content

Neuroblastoma and glioblastoma are the most commonly seen nervous system tumors, and their treatment is challenging. Relatively safe and easy acquisition of nutraceutical natural products make them suitable candidates for anticancer research. Royal jelly (RJ), a superfood, has many biological and pharmacological activities. This study was conducted to, for the first time, elucidate its anticancer efficiency, even in high doses, on neuroblastoma and glioblastoma cell lines through cell viability, apoptosis, cell cycle and biomolecular content evaluation. We performed experiments with RJ concentrations in the range of 1.25-10 mg mL-1 for 48 h. Cell viability assays revealed a notable cytotoxic effect of RJ in a concentration-dependent manner. Treatment with a high dose of RJ significantly increased the apoptotic cell population of both cell lines. Furthermore, we observed G0-G1 phase arrest in neuroblastoma cells but G2-M arrest in glioblastoma cells. All these cellular changes are closely associated with the alterations of the macromolecular makeup of the cells, such as decreased saturated lipid, protein, DNA and RNA amounts, protein conformational changes, decreased protein phosphorylation and increased protein carbonylation. These cellular changes are associated with RJ triggered-ROS formation. The clear segregation between the control and the RJ-treated groups proved these changes, obtained from the unsupervised and supervised chemometric analysis. RJ has good anticancer activity against nervous system cancers and could be safely used with current treatment strategies.

DUBing Primary Tumors of the Central Nervous System: Regulatory Roles of Deubiquitinases

The ubiquitin proteasome system (UPS) utilizes an orchestrated enzymatic cascade of E1, E2, and E3 ligases to add single or multiple ubiquitin-like molecules as post-translational modification (PTM) to proteins. Ubiquitination can alter protein functions and/or mark ubiquitinated proteins for proteasomal degradation but deubiquitinases (DUBs) can reverse protein ubiquitination. While the importance of DUBs as regulatory factors in the UPS is undisputed, many questions remain on DUB selectivity for protein targeting, their mechanism of action, and the impact of DUBs on the regulation of diverse biological processes. Furthermore, little is known about the expression and role of DUBs in tumors of the human central nervous system (CNS). In this comprehensive review, we have used publicly available transcriptional datasets to determine the gene expression profiles of 99 deubiquitinases (DUBs) from five major DUB families in seven primary pediatric and adult CNS tumor entities. Our analysis identified selected DUBs as potential new functional players and biomarkers with prognostic value in specific subtypes of primary CNS tumors. Collectively, our analysis highlights an emerging role for DUBs in regulating CNS tumor cell biology and offers a rationale for future therapeutic targeting of DUBs in CNS tumors.

Diagnostic and Therapeutic Approaches for Glioblastoma and Neuroblastoma Cancers Using Chlorotoxin Nanoparticles

Glioblastoma multiforme (GB) and high-risk neuroblastoma (NB) are known to have poor therapeutic outcomes. As for most cancers, chemotherapy and radiotherapy are the current mainstay treatments for GB and NB. However, the known limitations of systemic toxicity, drug resistance, poor targeted delivery, and inability to access the blood-brain barrier (BBB), make these treatments less satisfactory. Other treatment options have been investigated in many studies in the literature, especially nutraceutical and naturopathic products, most of which have also been reported to be poorly effective against these cancer types. This necessitates the development of treatment strategies with the potential to cross the BBB and specifically target cancer cells. Compounds that target the endopeptidase, matrix metalloproteinase 2 (MMP-2), have been reported to offer therapeutic insights for GB and NB since MMP-2 is known to be over-expressed in these cancers and plays significant roles in such physiological processes as angiogenesis, metastasis, and cellular invasion. Chlorotoxin (CTX) is a promising 36-amino acid peptide isolated from the venom of the deathstalker scorpion, Leiurus quinquestriatus, demonstrating high selectivity and binding affinity to a broad-spectrum of cancers, especially GB and NB through specific molecular targets, including MMP-2. The favorable characteristics of nanoparticles (NPs) such as their small sizes, large surface area for active targeting, BBB permeability, etc. make CTX-functionalized NPs (CTX-NPs) promising diagnostic and therapeutic applications for addressing the many challenges associated with these cancers. CTX-NPs may function by improving diffusion through the BBB, enabling increased localization of chemotherapeutic and genotherapeutic drugs to diseased cells specifically, enhancing imaging modalities such as magnetic resonance imaging (MRI), single-photon emission computed tomography (SPECT), optical imaging techniques, image-guided surgery, as well as improving the sensitization of radio-resistant cells to radiotherapy treatment. This review discusses the characteristics of GB and NB cancers, related treatment challenges as well as the potential of CTX and its functionalized NP formulations as targeting systems for diagnostic, therapeutic, and theranostic purposes. It also provides insights into the potential mechanisms through which CTX crosses the BBB to bind cancer cells and provides suggestions for the development and application of novel CTX-based formulations for the diagnosis and treatment of GB and NB in the future.

Targeting macrophage Syk enhances responses to immune checkpoint blockade and radiotherapy in high-risk neuroblastoma

Background

Neuroblastoma (NB) is considered an immunologically cold tumor and is usually less responsive to immune checkpoint blockade (ICB). Tumor-associated macrophages (TAMs) are highly infiltrated in NB tumors and promote immune escape and resistance to ICB. Hence therapeutic strategies targeting immunosuppressive TAMs can improve responses to ICB in NB. We recently discovered that spleen tyrosine kinase (Syk) reprograms TAMs toward an immunostimulatory phenotype and enhances T-cell responses in the lung adenocarcinoma model. Here we investigated if Syk is an immune-oncology target in NB and tested whether a novel immunotherapeutic approach utilizing Syk inhibitor together with radiation and ICB could provide a durable anti-tumor immune response in an MYCN amplified murine model of NB.

Methods

Myeloid Syk KO mice and syngeneic MYCN-amplified cell lines were used to elucidate the effect of myeloid Syk on the NB tumor microenvironment (TME). In addition, the effect of Syk inhibitor, R788, on anti-tumor immunity alone or in combination with anti-PDL1 mAb and radiation was also determined in murine NB models. The underlying mechanism of action of this novel therapeutic combination was also investigated.

Results

Herein, we report that Syk is a marker of NB-associated macrophages and plays a crucial role in promoting immunosuppression in the NB TME. We found that the blockade of Syk in NB-bearing mice markedly impairs tumor growth. This effect is facilitated by macrophages that become immunogenic in the absence of Syk, skewing the suppressive TME towards immunostimulation and activating anti-tumor immune responses. Moreover, combining FDA-approved Syk inhibitor, R788 (fostamatinib) along with anti-PDL1 mAb provides a synergistic effect leading to complete tumor regression and durable anti-tumor immunity in mice bearing small tumors (50 mm3) but not larger tumors (250 mm3). However, combining radiation to R788 and anti-PDL1 mAb prolongs the survival of mice bearing large NB9464 tumors.

Conclusion

Collectively, our findings demonstrate the central role of macrophage Syk in NB progression and demonstrate that Syk blockade can "reeducate" TAMs towards immunostimulatory phenotype, leading to enhanced T cell responses. These findings further support the clinical evaluation of fostamatinib alone or with radiation and ICB, as a novel therapeutic intervention in neuroblastoma.

Elevated exosome-transferrable lncRNA EPB41L4A-AS1 in CD56bright NK cells is responsible for the impaired NK function in neuroblastoma patients by suppressing cell glycolysis

NK cells are one of key immune components in neuroblastoma (NB) surveillance and eradication. Glucose metabolism as a major source of fuel for NK activation is exquisitely regulated. Our data revealed a diminished NK activation and a disproportionally augmented CD56^bright subset in NB. Further study showed that NK cells in NB presented with an arrested glycolysis accompanied by an elevated expression of the long noncoding RNA (lncRNA) EPB41L4A-AS1, a known crucial participant in glycolysis regulation, in the CD56^bright NK subset. The inhibitory function of lncRNA EPB41L4A-AS1 was recapitulated. Interestingly, our study demonstrated that exosomal lncRNA EPB41L4A-AS1 was transferrable from CD56^bright NK to CD56^dim NK and was able to quench the glycolysis of target NK. Our data demonstrated that an arrested glycolysis in patient NK cells was associated with an elevated lncRNA in CD56^bright NK subset and a cross-talk between heterogeneous NK subsets was achieved by transferring metabolic inhibitory lncRNA through exosomes.

A Novel Online Nomogram Established with Five Features before Surgical Resection for Predicating Prognosis of Neuroblastoma Children: A Population-Based Study

Background: Neuroblastoma (NB) is the most common childhood cancer, but doctors are unable to predict its overall survival (OS) rate before surgery. We aimed to predict the OS of NB children with some clinical features obtained from biopsy before surgery. Methods: Clinical features of NB children were retrospectively collected from the Therapeutically Applicable Research to Generate Effective Treatments database. The C-index, area under the receiver operating characteristic curve (AUC), calibration curves, and decision curves analysis were used to estimate nomogram models. Results: A total of 488 NB children were evaluated, and the Boruta algorithm was used to detect risk factors. The results showed that artificial neural networks with selected features were able to predict more than 90% of NB children. Five risk factors were used in the construction of the nomogram, including age at diagnosis, MYCN status, ploidy value, histology, and mitosis-karyorrhexis index (MKI). The C-index of the nomogram in training cohort and validation cohort was 0.716 and 0.731. AUC values for 1-, 3-, and 5-years OS predictions were 0.706, 0.755, and 0.762, respectively, and showed good calibrations. Decision curve analysis indicated a better predictability with the nomogram model based on Cox regression compared with one that included all variables and histology only. Also, the Kaplan-Meier curves showed a significantly higher survival probability in the low-risk group (total score <118.34) versus the high-risk group (total score ≥ 118.34) (p < 0.05) using the nomogram model. Conclusions: A web application based on the nomogram model in the present study can be accessed at https://mdzhou.shinyapps.io/DynNomapp/, which could help doctors make accurate clinical decisions about NB children.

Neuroblastoma Arising in an Immature Teratoma of the Ovary in a 13-Year-Old

Somatic malignancies arising in mature teratomas are exceedingly rare entities and even more so are those arising in immature teratomas. Here, we present a unique case of a 13-year-old who initially underwent ovarian sparing cystectomy for a 7.7 cm left ovarian mass with a pre-operative diagnosis of mature cystic teratoma. Histologically, all 3 germ cell layers were present and immature neuroepithelial tubules were also identified. Subsequent sections revealed a nodular lesion composed of neuropil, neuroblasts with a spectrum of maturation, and Schwannian-type stroma. The neuroblasts were diffusely positive for PHOX2B. Neuroblastoma arising in an immature teratoma has only been described in the literature once previously in an adult patient.

Research progress on the pharmacological effects of matrine

Matrine possesses anti-cancer properties, as well as the prevention and treatment of allergic asthma, and protection against cerebral ischemia-reperfusion injury. Its mechanism of action may be (1) regulation of cancer cell invasion, migration, proliferation, and cell cycle to inhibit tumor growth; (2) reduction of oxidized low-density lipoprotein and advanced glycation end products from the source by exerting anti-inflammatory and antioxidant effects; (3) protection of brain damage and cortical neurons by regulating apoptosis; (4) restoration of the intestinal barrier and regulation of the intestinal microbiota. This article aims to explore matrine’s therapeutic potential by summarizing comprehensive information on matrine’s pharmacology, toxicity, and bioavailability.

Gene-Environment Interactions During the First Thousand Days Influence Childhood Neurological Diagnosis

Gene-environment (G x E) interactions significantly influence neurologic outcomes. The maternal-placental-fetal (MPF) triad, neonate, or child less than 2 years may first exhibit significant brain disorders. Neuroplasticity during the first 1000 days will more likely result in life-long effects given critical periods of development. Developmental origins and life-course principles help recognize changing neurologic phenotypes across ages. Dual diagnostic approaches are discussed using representative case scenarios to highlight time-dependent G x E interactions that contribute to neurologic sequelae. Horizontal analyses identify clinically relevant phenotypic form and function at different ages. Vertical analyses integrate the approach using systems-biology from genetic through multi-organ system interactions during each developmental age to understand etiopathogenesis. The process of ontogenetic adaptation results in immediate or delayed positive and negative outcomes specific to the developmental niche, expressed either as a healthy child or one with neurologic sequelae. Maternal immune activation, ischemic placental disease, and fetal inflammatory response represent prenatal disease pathways that contribute to fetal brain injuries. These processes involve G x E interactions within the MPF triad, phenotypically expressed as fetal brain malformations or destructive injuries within the MPF triad. A neonatal minority express encephalopathy, seizures, stroke, and encephalopathy of prematurity as a continuum of trimester-specific G x E interactions. This group may later present with childhood sequelae. A healthy neonatal majority present at older ages with sequelae such as developmental disorders, epilepsy, mental health diseases, tumors, and neurodegenerative disease, often during the first 1000 days. Effective preventive, rescue, and reparative neuroprotective strategies require consideration of G x E interactions interplay over time. Addressing maternal and pediatric health disparities will maximize medical equity with positive global outcomes that reduce the burden of neurologic diseases across the lifespan.

The PRC2 molecule EED is a target of epigenetic therapy for neuroblastoma

Epigenetic modifications by polycomb repressive complex (PRC) molecules appear to play a role in the tumorigenesis and aggressiveness of neuroblastoma (NB). Embryonic ectoderm development (EED) is a member of the PRC2 complex that binds to the H3K27me3 mark deposited by EZH2 via propagation on adjacent nucleosomes. We herein investigated the molecular roles of EED in MYCN-amplified NB cells using EED-knockdown (KD) shRNAs, EED-knockout sgRNAs, and the EED small molecule inhibitor EED226. The suppression of EED markedly inhibited NB cell proliferation and flat and soft agar colony formation. A transcriptome analysis using microarrays of EED-KD NB cells indicated the de-repression of cell cycle-regulated and differentiation-related genes. The results of a GSEA analysis suggested that inhibitory cell cycle-regulated gene sets were markedly up-regulated. Furthermore, an epigenetic treatment with the EED inhibitor EED226 and the HDAC inhibitors valproic acid/SAHA effectively suppressed NB cell proliferation and colony formation. This combined epigenetic treatment up-regulated cell cycle-regulated and differentiation-related genes. The ChIP sequencing analysis of histone codes and PRC molecules suggested an epigenetic background for the de-repression of down-regulated genes in MYCN-amplified/PRC2 up-regulated NB.

Silencing of long chain noncoding RNA paternally expressed gene (PEG10) inhibits the progression of neuroblastoma by regulating microRNA-449a (miR-449a)/ribosomal protein S2 (RPS2) axis

To investigate the mechanism of paternally expressed gene (PEG10) in regulating neuroblastoma (NB) progression. PEG10 expression was detected using quantitative real-time reverse transcription polymerase-chain reaction (qRT-PCR). The interaction of miR-449a and PEG10 or ribosomal protein S2 (RPS2) was employed by starBase, and then proved through RIP and dual-luciferase reporter assays. The NB cell viability, proliferation, invasion, and migration were evaluated by Cell Counting Kit-8 (CCK-8), colony formation, and Transwell assay. The mRNA and protein levels were determined by qRT-PCR and Western blotting, respectively. The levels of PEG10 and RPS2 were remarkably increased in NB tissues and cells, nevertheless the expression of miR-449a was conspicuously declined in NB tissues and cells. Silencing of PEG10 inhibited proliferation, migration, and invasion in SK-N-BE (2) cells, while overexpression of PEG10 promoted proliferation, migration, and invasion in SH-SY5Y cells. We affirmed that PEG10 interacted with miR-449a, and miR-449a could target the 3'UTR of RPS2 and negatively regulate its expression in NB cells. The upregulation of miR-449a inhibited proliferation, migration, and invasion in SK-N-BE (2) cells, while downregulation of miR-449a promoted proliferation, migration, and invasion in SH-SY5Y cells. Moreover, miR-449a overexpression weaken the function of PEG10-mediated on promoting proliferation, migration, and invasion in SH-SY5Y cells, while RPS2 overexpression rescued the effects of miR-449a-mediated on inhibiting those behaviors of SH-SY5Y cells. In conclusion, Silencing of PEG10 could inhibit proliferation, migration, and invasion via the miR-449a/RPS2 axis in NB cells.

CircRNA-ACAP2 contributes to the invasion, migration, and anti-apoptosis of neuroblastoma cells through targeting the miRNA-143-3p-hexokinase 2 axis

BACKGROUND

Circulating RNAs (Circ-RNAs) are tightly related to the processes of neuroblastoma. The circ-ACAP2 has been reported as dysregulated in various cancers; however, its biological roles and mechanisms in neuroblastoma remain largely unclear.

METHODS

We collected 40 neuroblastoma tissues and adjacent noncancerous tissues. Quantitative reverse transcription polymerase chain reaction (qRT-RCR) or western blot were used to examine ACAP2, miR-143-3p, and HK2 abundances. Cell migration, invasion, glycolysis, and apoptosis were assessed via wound healing, transwell, glucose uptake and lactate, 3-(4,5-diamethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, and flow cytometry. The association between circRNA, microRNA (miRNA), and messenger RNA (mRNA) was examined by dual-luciferase reporter analysis and RNA immunoprecipitation.

RESULTS

The abundances of ACAP2 and HK2 were remarkedly increased in neuroblastoma tissues and cell lines. Silencing ACAP2 significantly constrained neuroblastoma cell migration, invasion, and glycolysis, and promoted apoptosis. Bioinformatics prediction, luciferase assay, and RNA pull-down assay consistently demonstrated that ACAP2 sponged miR-143-3p to downregulate its expression in neuroblastoma cells. Furthermore, we identified that hexokinase 2, a glycolysis key enzyme, was a direct target of miR-143-3p in neuroblastoma cells. Rescue of miR-143-3p in ACAP2-overexpressing cells effectively mitigated the influence of ACAP2 on neuroblastoma cell processes.

CONCLUSIONS

Our study revealed biological roles and molecular mechanisms for circ-ACAP2 in the oncogenic characteristics of neuroblastoma, facilitating the development of circRNA-based treatment approaches for anti-brain tumor therapy.

GD2-specific chimeric antigen receptor-modified T cells for the treatment of refractory and/or recurrent neuroblastoma in pediatric patients

Purpose

This study aimed to evaluate the safety and efficacy of chimeric antigen receptor (CAR) disialoganglioside 2 (GD2)-specific (4SCAR-GD2) T cells for treatment of refractory and/or recurrent neuroblastoma (NB) in pediatric patients.

Experimental design

A phase I clinical study using 4SCAR-GD2 T cells for the treatment of NB in pediatric patients was conducted. This study was registered at www.clinicaltrials.gov (NCT02765243). A lentiviral CAR with the signaling domains of CD28/4-1BB/CD3ζ-iCasp9 was transduced into activated T cells. The response to 4SCAR-GD2 T-cell treatment, and 4SCAR-GD2 T-cell expansion and persistence in patients were evaluated. Toxicities were determined based on the National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE) v4.03.

Results

Twelve patients were enrolled and finally ten patients were included in this clinical trial which started from January 1, 2016, to August 1, 2017. These patients had progressive disease (PD) before CAR T-cell infusion. After 4SCAR-GD2 T-cell treatment, 6 (6/10) had stable disease (SD) at 6 months, and 4 (4/10) remained SD at 1 year and alive after 3–4 years of follow-up. Six patients died due to disease progression by the end of July 1, 2020. The median overall survival (OS) time was 25 months (95% CI, 0.00–59.43), and the median progression-free survival (PFS) time was 8 months (95% CI, 0.25–15.75). Grade 3 or 4 hematological toxicities were the common adverse events frequently occurred after fludarabine and cyclophosphamide (Flu/cy) chemotherapy. Grade 1–2 toxicities such as cytokine release syndrome (CRS) and neuropathic pain were common, but were transient and mild.

Conclusions

The 4SCAR-GD2 T-cell therapy demonstrated antitumor effect and manageable toxicities, indicating its potential to benefit children with refractory and/or recurrent NB.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00432-021-03839-5.

Deciphering the selective binding mechanisms of anaplastic lymphoma kinase-derived neuroblastoma tumor neoepitopes to human leukocyte antigen

Neuroblastoma (NB), as a metastatic form of solid tumor, has a high fatality rate found in early childhood. The two anaplastic lymphoma kinase (ALK) neoepitopes nonamer and decamer used in cancer immunotherapy against NB cancer can selectively bind to the human leukocyte antigen (HLA-B*15:01) groove with high affinities, whereas the native self-peptide is unable to interact with the HLA-B*15:01. Here, we performed molecular dynamics (MD) simulations and subsequent molecular mechanics-generalized born surface area (MM-GBSA) binding free energy calculations to explore the selective binding mechanisms of nonamer and decamer to the HLA-B*15:01 against the self-peptide. MD simulations revealed the significant conformational dynamics of the self-peptide in the HLA-B*15:01 groove against the nonamer and decamer. Binding free energy calculations showed that the binding affinities of HLA-B*15:01-neoepitope complexes were followed in the order decamer > nonamer > self-peptide. Detailed analysis of HLA-B*15:01-neoepitope structural complexes showed that compared to the nonamer, the self-peptide tended to move outward to the solvent, whereas the decamer moved deep to the HLA-B*15:01 groove. These different dynamic observations of the ALK neoepitopes can explain the distinct binding affinities of self-peptide, nonamer, and decamer to the HLA-B*15:01. The results may be useful for the design of more selective ALK neoepitopes.

MYCN Drives a Tumor Immunosuppressive Environment Which Impacts Survival in Neuroblastoma

A wide range of malignancies presents MYCN amplification (MNA) or dysregulation. MYCN is associated with poor prognosis and its over-expression leads to several dysregulations including metabolic reprogramming, mitochondria alteration, and cancer stem cell phenotype. Some hints suggest that MYCN overexpression leads to cancer immune-escape. However, this relationship presents various open questions. Our work investigated in details the relationship of MYCN with the immune system, finding a correlated immune-suppressive phenotype in neuroblastoma (NB) and different cancers where MYCN is up-regulated. We found a downregulated Th1-lymphocytes/M1-Macrophages axis and upregulated Th2-lymphocytes/M2-macrophages in MNA NB patients. Moreover, we unveiled a complex immune network orchestrated by N-Myc and we identified 16 genes modules associated to MNA NB. We also identified a MYCN-associated immune signature that has a prognostic value in NB and recapitulates clinical features. Our signature also discriminates patients with poor survival in non-MNA NB patients where MYCN expression is not discriminative. Finally, we showed that targeted inhibition of MYCN by BGA002 (anti-MYCN antigene PNA) is able to restore NK sensibility in MYCN-expressing NB cells. Overall, our study unveils a MYCN-driven immune network in NB and shows a therapeutic option to restore sensibility to immune cells.

Matrine Can Inhibit the Growth of Colorectal Cancer Cells by Inducing Ferroptosis

Colorectal cancer (CRC) is a common malignant tumor of the digestive system that can seriously threaten human health. Chinese matrine is known to have a wide range of antiviral and immunomodulatory effects. In this study, we evaluated the effect of matrine on ferroptosis using the HCT116 human colon cancer cell line. We evaluated cell viability and proliferation using the cell counting kit-8 assay and carried out cell clone formation experiment by measuring reactive oxygen species (ROS) production, as well as levels of glutathione (GSH), lipid peroxide (MDA), Fe2+, glutathione peroxidase 4 (GPX4), activating transcription factor 4 (ATF4), solute carrier family 7 member 11 (SLC7A11), transferrin receptor protein 2 (TFR2), and Sigma-1 receptor (Sigma-1R) in order to evaluate the redox status of cells. These results indicate that matrine can significantly reduce the cell viability of HCT116 and decrease cell proliferation. After treatment with matrine, ROS, Fe2+, and MDA levels increased significantly, while the GSH content decreased. In addition, the expression of GPX4, SLC7A11, and Sigma-1R decreased significantly, while the expression of ATF4 and TFR2 increased significantly. These results indicate that matrine can induce ferroptosis in CRC, which can provide new clues for further pharmacological research of matrine and provide experimental evidence for understanding its mechanism of inhibiting CRC.

Targeting the p53-MDM2 pathway for neuroblastoma therapy: Rays of hope

Despite being the subject of extensive research and clinical trials, neuroblastoma remains a major therapeutic challenge in pediatric oncology. The p53 protein is a central safeguard that protects cells against genome instability and malignant transformation. Mutated TP53 (the gene encoding p53) is implicated in many human cancers, but the majority of neuroblastomas have wild type p53 with intact transcriptional function. In fact, the TP53 mutation rate does not exceed 1-2% in neuroblastomas. However, overexpression of the murine double minute 2 (MDM2) gene in neuroblastoma is relatively common, and leads to inhibition of p53. It is also associated with other non-canonical p53-independent functions, including drug resistance and increased translation of MYCN and VEGF mRNA. The p53-MDM2 pathway in neuroblastoma is also modulated at several different molecular levels, including via interactions with other proteins (MYCN, p14^ARF). In addition, the overexpression of MDM2 in tumors is linked to a poorer prognosis for cancer patients. Thus, restoring p53 function by inhibiting its interaction with MDM2 is a potential therapeutic strategy for neuroblastoma. A number of p53-MDM2 antagonists have been designed and studied for this purpose. This review summarizes the current understanding of p53 biology and the p53-dependent and -independent oncogenic functions of MDM2 in neuroblastoma, and also the regulation of the p53-MDM2 axis in neuroblastoma. This review also highlights the use of MDM2 as a molecular target for the disease, and describes the MDM2 inhibitors currently being investigated in preclinical and clinical studies. We also briefly explain the various strategies that have been used and future directions to take in the development of effective MDM2 inhibitors for neuroblastoma.