Variant rs8400 enhances ALKBH5 expression through disrupting miR-186 binding and promotes neuroblastoma progression

Objective:AlkB homolog 5(ALKBH5)has been proven to be closely related to tumors.However,the role and molecular mechanism of ALKBH5 in neuroblastomas have rarely been reported.Methods:The potential functional single-nucleotide polymorphisms(SNPs)in ALKBH5 were identified by National Center for Biotechnology Information(NCBI)dbSNP screening and SNPinfo software.TaqMan probes were used for genotyping.A multiple logistic regression model was used to evaluate the effects of different SNP loci on the risk of neuroblastoma.The expression of ALKBH5 in neuroblastoma was evaluated by Western blotting and immunohistochemistry(IHC).Cell counting kit-8(CCK-8),plate colony formation and 5-ethynyl-2'-deoxyuridine(EdU)incorporation assays were used to evaluate cell proliferation.Wound healing and Transwell assays were used to compare cell migration and invasion.Thermodynamic modelling was performed to predict the ability of miRNAs to bind to ALKBH5 with the rs8400 G/A polymorphism.RNA sequencing,N6-methyladenosine(mA)sequencing,mA methylated RNA immunoprecipitation(MeRIP)and a luciferase assay were used to identify the targeting effect of ALKBH5 on SPP1.Results:ALKBH5 was highly expressed in neuroblastoma.Knocking down ALKBH5 inhibited the proliferation,migration and invasion of cancer cells.miR-186-3p negatively regulates the expression of ALKBH5,and this ability is affected by the rs8400 polymorphism.When the G nucleotide was mutated to A,the ability of miR-186-3p to bind to the 3'-UTR of ALKBH5 decreased,resulting in upregulation of ALKBH5.SPPI is the downstream target gene of the ALKBH5 oncogene.Knocking down SPP1 partially restored the inhibitory effect of ALKBH5 downregulation on neuroblastoma.Downregulation of ALKBH5 can improve the therapeutic efficacy of carboplatin and etoposide in neuroblastoma.Conclusions:We first found that the rs8400 G>A polymorphism in the m6A demethylase-encoding gene ALKBH5 increases neuroblastoma susceptibility and determines the related mechanisms.The aberrant regulation of ALKBH5 by miR-186-3p caused by this genetic variation in ALKBH5 promotes the occurrence and development of neuroblastoma through the ALKBH5-SPP1 axis.

Progress in building clinically relevant patient-derived tumor xenograft models for cancer research

Patient-derived tumor xenograft(PDX)models,a method involving the surgical extraction of tumor tissues from cancer patients and subsequent transplantation into immunodeficient mice,have emerged as a pivotal approach in translational research,particularly in advancing precision medicine.As the first stage of PDX development,the patient-derived orthotopic xenograft(PDOX)models implant tumor tissue in mice in the corresponding anatomical locations of the patient.The PDOX models have several advantages,including high fidelity to the original tumor,heightened drug sensitivity,and an elevated rate of successful transplantation.However,the PDOX models present significant challenges,requiring advanced surgical techniques and resourceintensive imaging technologies,which limit its application.And then,the humanized mouse models,as well as the zebrafish models,were developed.Humanized mouse models contain a human immune environment resembling the tumor and immune system interplay.The humanized mouse models are a hot topic in PDX model research.Regarding zebrafish patient-derived tumor xenografts(zPDX)and patient-derived organoids(PDO)as promising models for studying cancer and drug discovery,zPDX models are used to transplant tumors into zebrafish as novel personalized medical animal models with the advantage of reducing patient waiting time.PDO models provide a cost-effective approach for drug testing that replicates the in vivo environment and preserves important tumor-related information for patients.The present review highlights the functional characteristics of each new phase of PDX and provides insights into the challenges and prospective developments in this rapidly evolving field.

ALKBH5 gene polymorphisms and risk of neuroblastoma in Chinese children from Jiangsu Province

Background:Neuroblastoma is one of the most common extracranial malignant solid tumors in children.AlkB homolog 5(ALKBH5)is an RNA N6-methyladenosine(m6A)demethylase that plays a critical role in tumorigenesis and development.We assessed the association between single nucleotide polymorphisms(SNPs)in ALKBH5 and the risk of neuroblastoma in a case-control study including 402 patients and 473 non-cancer controls.Methods:Genotyping was determined by the TaqMan method.The association between ALKBH5 polymorphisms(rs1378602 and rs8400)and the risk of neuroblastoma was evaluated using the odds ratio(OR)and 95%confidence interval(CI).Results:We found no strong association of ALKBH5 rs1378602 and rs8400 with neuroblastoma risk.Further stratification analysis by age,sex,primary site,and clinical stage showed that the rs1378602 AG/AA genotype was associated with a lower risk of neuroblastoma in males(adjusted OR=0.58,95%CI=0.35–0.97,p=0.036)and children with retroperitoneal neuroblastoma(adjusted OR=0.58,95%CI=0.34–0.98,p=0.040).Conclusions:ALKBH5 SNPs do not seem to be associated with neuroblastoma risk.More studies are required to confirm this negative result and reveal the relationship between gene polymorphisms of the m6A modifier ALKBH5 and neuroblastoma.

PTBP2-Mediated Alternative Splicing of IRF9 Controls Tumor-Associated Monocyte/Macrophage Chemotaxis and Repolarization in Neuroblastoma Progression

The recurrence and metastasis of children with mediastinal neuroblastoma(NB)are also occurred after surgery,chemotherapy,or radiotherapy.Strategies targeting the tumor microenvironment have been reported to improve survival;however,thorough investigations of monocytes and tumor-associated macrophages(Mϕs)with specialized functions in NB are still lacking.Our data first demonstrated polypyrimidine tract binding protein 2(PTBP2)as a possible identifier in patients with mediastinal NB screened by proteomic profiling and that PTBP2 predicted good outcomes.Functional studies revealed that PTBP2 in NB cells induced the chemotactic activity and repolarization of tumor-associated monocytes and Mϕs,which,in turn,inhibited NB growth and dissemination.Mechanistically,PTBP2 prevents interferon regulatory factor 9 alternative splicing and upregulates signal transducers and activators of transcription 1 to stimulate C-C motif chemokine ligand 5(CCL5)and interferon-stimulated gene factor-dependent type I interferon secretion,to induce monocyte/Mϕs chemotaxis,and to sustain monocytes in a proinflammatory phenotype.Our study defined a critical event of PTBP2-induced monocytes/Mϕs in NB progression and revealed that RNA splicing occurred by PTBP2 benefits immune compartmentalization between NB cells and monocytes.This work revealed the pathological and biological role of PTBP2 in NB development and indicates that PTBP2-induced RNA splicing benefits immune compartmentalization and predicted a favorable prognosis in mediastinal NB.

Association of ERCC1 and XPF polymorphisms with pediatric glioma susceptibility

To the Editor:Glioma is a highly invasive and lethal heterogeneous disease caused by glial or precursor cell mutation.It accounts for about 50%of tumors in children and 80%of malignant tumors.[1]The nucleotide excision repair(NER)pathway is a process that involves the sequential assembly of many proteins,including excision repair cross complementation group 1(ERCC1)and xeroderma pigmentosum complementation group F(XPF,also known as ERCC4).

Correlation between the genetic variants of base excision repair (BER) pathway genes and neuroblastoma susceptibility in eastern Chinese children

Dear Editor,Neuroblastoma is the most common non-central nerve system(CNS)solid tumor in pediatrics[1].Neuroblastoma accounts for approximately 8%of all pediatric cancers but disproportionally causes a high cancer mortality(15%)in children[2].Pediatric patients with low-risk neuroblastoma witness a 5-year overall survival rate>90%,whereas the 5-year overall survival rate in high-risk neuroblastoma pediatric patients is<40%[3].

Associations between LMO1 gene polymorphisms and central nervous system tumor susceptibility

Importance:LIM domain only 1(LMO1)gene polymorphisms were previously found to be implicated in the risk of several cancers.No available studies were performed regarding the predisposing effect of LMO1 gene single nucleotide polymorphisms(SNPs)on central nervous system(CNS)tumor risk.Objective:We aimed to determine whether the LMO1 gene SNPs were associated with the risk of CNS tumor by applying a case-control study with 191 cases and 248 controls in China.Methods:The contributions of LMO1 gene SNPs to the risk of CNS tumor was evaluated by multinomial logistic regression.Results:Based on the calculations of odds ratio(OR)and 95%confidence interval(CI),we failed to detect a significant relationship between each LMO1 gene SNP(rs110419 A>G,rs4758051 G>A,rs10840002 A>G,rs204938 A>G,and rs2168101 G>T)and CNS tumor risk,respectively.A negative association was also found in the combined effects on these five SNPs and CNS tumor risk.The stratification analysis further demonstrated the individuals with rs204938 AG/GG genotype confer to increased risk of CNS tumor compared with those with an AA genotype in males(OR:1.74,95%CI:1.01-2.98,P=0.046).Interpretation:We concluded that LMO1 gene SNPs may not strong enough to influence the risk of CNS tumor in Chinese children.More studies are required to verify this association.

Advances in liquid biopsy in neuroblastoma

Even with intensive treatment of high-risk neuroblastoma(NB)patients,half of high-risk NB patients still relapse.New therapies targeting the biological characteristics of NB have important clinical value for the personalized treatment of NB.However,the current biological markers for NB are mainly analyzed by tissue biopsy.In recent years,circulating biomarkers of NB based on liquid biopsy have attracted more and more attention.This review summarizes the analytes and methods for liquid biopsy of NB.We focus on the application of liquid biopsy in the diagnosis,prognosis assessment,and monitoring of NB.Finally,we discuss the prospects and challenges of liquid biopsy in NB.

The Role of Anaplastic Lymphoma Kinase Receptor in Neuroblastoma

Neuroblastoma(NB),a frequently occurring pediatric disease,is derived from the neural crest cells in the sympathetic ganglia and adrenal medulla.Notably,it is a heterogeneous tumor consisting of many affection factors,such as the diagnosis time within the first year and the diversity of the histology and genetic features.Despite improved outcomes in NB patients,it remains a difficult clinical problem and requires new therapeutic targets and methods.The somatic acquired activation point mutations in the receptor tyrosine kinase anaplastic lymphoma kinase(ALK)represent potential targets for treating NB.Herein,we review the underlying mechanisms of ALK in NB development,the latest available strategies to block ALK constitutive activity to treat NB,and discuss the current clinical challenges of resistance to these therapies and the strategies to overcome them.