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Objective:To explore the genetic etiology and clinical phenotype of Feingold syndrome due to chromosome 2p24.3p24.2 microdeletion.Methods:The clinical data of a child admitted to Henan Provincial People′s Hospital in November 2021 and diagnosed as Feingold syndrome type 1 (FGLDS1) associated with chromosome 2p24.3p24.2 microdeletion were collected. The clinical and genetic variation characteristics of the patient were summarized, and 10 patients with chromosome 2p microdeletion reported until November 2022 were reviewed.Results:The boy was 12 years and 5 months old. He presented with backward physical development, motor development retardation, low intelligence, special body and facial appearance, finger developmental deformity and other manifestations, accompanied by hyperactivity and aggressive behavior, impulsive irritability, self-injury and other behavior problems. The proband showed normal chromosome karyotype; the genome-wide copy number variant sequencing and trio-whole exome sequencing revealed a 2.61 Mb deletion at chromosome 2p24.3p24.2 region, and 10 genes including MYCN gene (exons 1 to 3) in the deleted region.The same deletion was not found in either of his parents. The genetic features of 11 cases (including this case) with chromosome 2p microdeletion were summarized, all of whom had insufficient haploid dosage of the MYCN gene due to chromosome 2p microdeletion, and the clinical manifestations of these 11 patients matched the clinical diagnosis of FGLDS1. Conclusion:The proband is consistent with the clinical presentation of the typical Feingold syndrome, and the haploinsufficiency of the MYCN gene due to the microdeletion of chromosome 2 is the genetic etiology of the proband.

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The MYCC and MYCN loci are each associated with two upstream open reading frames (uORFs) potentially encoding small proteins (9-21 kDa). We previously demonstrated that uORFs mrtl and MYCHEX1 of MYCC are translated, and their protein products may function to regulate the expression of the "parent" oncogene. We hypothesized that a similar relationship might exist between MYCN and its two uORFs: MYCNOT and MNOP, and investigated the uORF-encoded proteins associated with MYCN to confirm their expression and intracellular location in neuroblastoma and medulloblastoma cells and tissues. MNOP, MYCNOT, mrtl, and MYCHEX1 were readily detected via reverse transcription polymerase chain reaction and Western blot analysis in tumor cell lines. In tumor tissue, MNOP protein expression was confirmed; however, MCYNOT generated from alternative splicing MYCNΔ1b mRNA was not detected. Immunofluorescence staining of MYCNOT displayed multiple bright foci in the nucleus and diffuse staining in the cytoplasm, suggesting that this small protein may function in both the nucleus and cytoplasm. Upon JQ1 treatment, MYCN, MYCNOT, and mrtl decreased substantially or disappeared completely in three different tumor cell lines. Significant levels of apoptosis were observed in each pediatric embryonal tumor cell line but not T47D breast carcinoma cells, suggesting that response to JQ1 transcriptional inhibition is greatest in tumor cells, which depend on MYC to maintain an undifferentiated phenotype. In conclusion, both MYCN uORF-encoded proteins MNOP and MYCNOT, together with the two MYCC uORF-encoded proteins mrtl and MYCHEX1 were detected simultaneously in tumor cell lines and tumor tissues. These four distinct proteins are translated from the "5'-untranslated region" of MYCN or MYCC mRNA and display consistent distribution patterns within the cell. Additional studies to further elucidate the physiological and pathological roles of these uORF-encoded proteins are warranted, as insights gained could inform new strategies for modulating MYC-family oncogenes by targeting their uORFs.

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Neuroblastoma (NB) is the most common solid malignancy in children. MYCN gene amplification is the most relevant genetic alteration in patients with NB and is associated with poor prognosis. Autophagy plays specific roles in the occurrence, development, and progression of NB. Here, we aimed to identify and assess the prognostic effects of autophagy-related genes (ARGs) in patients with NB and MYCN gene amplification. Differentially expressed ARGs were identified in patients with NB with and without MYCN gene amplification, and the ARG expression patterns and related clinical data from the Therapeutically Applicable Research to Generate Effective Treatments database were used as the training cohort. Least absolute shrinkage and selection operator analyses were used to identify prognostic ARGs associated with event-free survival (EFS), and a prognostic risk score model was developed. Model performance was assessed using the Kaplan-Meier method and receiver operating characteristic (ROC) curves. The prognostic ARG mode l was verified using the validation cohort dataset, GSE49710. Finally, a nomogram was constructed by combining the ARGbased risk score with clinicopathological factors. Three ARGs (GABARAPL1, NBR1, and PINK1) were selected to build a prognostic risk score model. The EFS in the low-risk group was significantly better than that in the high-risk group in both the training and validation cohorts. A nomogram incorporating the prognostic risk score, age, and International Neuroblastoma Staging System stage showed a favorable predictive ability for EFS rates according to the area under the ROC curve at 3 years (AUC = 0.787) and 5 years (AUC = 0.787). The nomogram demonstrated good discrimination and calibration. Our risk score model for the 3 ARGs can be used as an independent prognostic factor in patients with NB and MYCN gene amplification. The model can accurately predict the 3- and 5-year survival rates.

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Objective:To explore the clinical significance of the MYCN gene, PHOX2B gene and plasma cell-free DNA (cfDNA) in risk stratification and predicting the prognosis of high-risk neuroblastoma (NB). Methods:This was a prospective study involving 94 high-risk NB children admitted to Beijing Children′s Hospital, Capital Medical University from August 2017 to December 2018.Relative levels of MYCN and PHOX2B and cfDNA at diagnosis, and 4 and 6 cycles of chemotherapy were detected, and their differences were compared by the Chi- square test.Kaplan-Meier survival analysis was performed to explore their prognostic potential in high-risk NB. Results:Among the 94 high-risk NB children, 14 cases (14.9%) had MYCN amplification, 76 cases (80.8%) had positive expression of PHOX2B and 56 cases (59.6%) had cfDNA level higher than 100 μg/L.The proportion of high lactate dehydrogenase (LDH, ≥1 500 U/L) level in the MYCN gene amplification group (6/14 cases) was higher than that in the normal group (9/80 cases) ( P=0.009). The proportion of multi-site metastasis (54/76 cases) and high neuron specific enolase (NSE) level (NSE≥370 μg/L, 37/76 cases) in PHOX2B positive group were significantly higher than those in the negative group (5/14 cases, 2/14 cases) ( P=0.015, 0.020). The proportion of high LDH and high NSE in high cfDNA concentration (≥229.6 μg/L)group (13/37 cases, 28/37 cases) were significantly higher than those in low cfDNA concentration group (2/48 cases, 10/48 cases) (all P<0.001). With the decreased tumor burden during the treatment, the copy number of PHOX2B gene and cfDNA level were significantly lower than those at the initial diagnosis [0 (0-719.6) copies vs.1 723.5 (0-186 000.0) copies; 19.0 (1.1-225.5) μg/L vs.200.6 (8.0-5 247.4) μg/L, all P<0.001]. The 2-year event-free survival (EFS) rate of the MYCN gene amplification group was significantly lower than that of the normal group[(33.3±13.1)% vs.(58.5±7.1)%, P=0.020]. The 2-year EFS rate of PHOX2B positive group was significantly lower than that of the negative group[(47.9±7.1)% vs.(79.1±11.1)%, P=0.043]. EFS rate in high cfDNA concentration group was significantly lower than that in cfDNA low concentration group[(38.6±9.8)% vs.( 71.7±8.2)%, P=0.001]. After 6 cycles of chemotherapy, EFS rate in the PHOX2B positive group was significantly lower than that in the negative group [(16.7±14.4)% vs.( 60.6±6.6)%, P=0.014]; which was significantly lower in the Metaiodobenzylguanidine (MIBG) positive group than that of the negative group[(35.2±11.7)% vs.(65.8±7.1)%, P=0.037]. The MYCN gene and cfDNA concentration were not correlated with the prognosis of high-risk NB.Survival analysis of the combination of PHOX2B and MYCN gene ( PHOX2B+ /MIBG + , PHOX2B+ or MIBG + , PHOX2B-/MIBG -) showed a significant difference in the survival among three groups[0 vs.(53.6±1.2)% vs.(65.5±7.4)%, P=0.003]. Conclusions:The MYCN and PHOX2B gene and cfDNA concentration are of significance in risk stratification and predicting the prognosis of high-risk NB.Compared with the MYCN gene and cfDNA concentration, the PHOX2B gene is more suitable for monitoring the curative effect of chemotherapy on high-risk NB.A combined analysis of PHOX2B gene and MIBG before treatment can be more accurate in evaluating the treatment effect and residual lesions.

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BACKGROUND: Neuroblastoma (NB) is a heterogeneous disease with respect to genomic abnormalities and clinical behaviors. Despite recent advances in our understanding of the association between the genetic aberrations and clinical features, it remains one of the major challenges to predict prognosis and stratify patients for determining personalized therapy in this disease. The aim of this study was to develop an effective prognosis prediction model for NB patients. METHODS: We integrated diverse computational analyses to define gene signatures that reflect MYCN activity and chromosomal aberrations including deletion of chromosome 1p (Chr1p_del) and chromosome 11q (Chr11q_del) as well as chromosome 11q whole loss (Chr11q_wls). We evaluated the prognostic and predictive values of these signatures in seven NB gene expression datasets (the number of samples ranges from 94 to 498, with a total of 2120) generated from both RNA sequencing and microarray platforms. RESULTS: MYCN signature was a more effective prognostic marker than MYCN amplification status and MYCN expression. Similarly, the Chr1p_del score was more prognostic than Chr1p status. The activity scores of MYCN, Chr1p_del and Chr11q_del were associated with poor prognosis, while the Chr11q_wls score was linked to good outcome. We integrated the activity scores of MYCN, Chr1p_del, Chr11q_del, and Chr11q_wls and clinical variables into an integrative prognostic model, which displayed significant performance over the clinical variables or each genomic aberration alone. CONCLUSIONS: Our integrative gene signature model shows a significantly improved forecast performance with prognostic and predictive information, and thereby can be served as a biomarker to stratify NB patients for prognosis evaluation and surveillance programs.

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Childhood neuroblastoma, a disease of the sympathetic nervous system, is the most common solid tumour of infancy, remarkably refractory to therapeutic treatments. One of the most powerful independent prognostic indicators for this disease is the amplification of the MYCN oncogene, which occurs at high levels in approximately 25% of neuroblastomas. Interestingly, amplification and not just expression of MYCN has a strong prognostic value, although this fact appears quite surprising as MYCN is a transcription factor that requires dimerising with its partner MAX, to exert its function. This observation greatly suggests that the role of MYCN in neuroblastoma should be examined in the context of MAX expression. In this report, we show that, in contrast to what is found in normal cells, MAX expression is significantly different among primary NBs, and that its level appears to correlate with the clinical outcome of the disease. Importantly, controlled modulation of MAX expression in neuroblastoma cells with different extents of MYCN amplification, demonstrates that MAX can instruct gene transcription programs that either reinforce or weaken the oncogenic process enacted by MYCN. In general, our work illustrates that it is the MAX to MYCN ratio that can account for tumour progression and clinical outcome in neuroblastoma and proposes that such a ratio should be considered as an important criterion to the design and development of anti-MYCN therapies.

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PURPOSE: Neuroblastoma is a refractory pediatric malignant solid tumor. The previous studies demonstrated that Polyphyllin D, the main constituent of Paris polyphylla, a traditional Chinese medicine, exerts an anti-tumor effect on many tumors. However, its effects against neuroblastomas are unclear. METHODS: We examined the anti-tumor effect of polyphyllin D in human neuroblastoma using IMR-32 and LA-N-2 cells, which exhibit MYCN gene amplification, and NB-69 cells, which do not exhibit MYCN gene amplification. RESULTS: All cell lines showed reduced cell viability in response to polyphyllin D treatment. No caspase-3/-7, -8, and -9 activity was observed in IMR-32 and LA-N-2 cells treated with polyphyllin D. In contrast, activation of caspase-3/-7, and -8 activity was observed in NB-69 cells. When polyphyllin D and specific inhibitors of RIPK3 involved in necroptosis were added to IMR-32 and LA-N-2 cell lines, polyphyllin D-induced cell death was inhibited. CONCLUSION: Together, this indicates that the underlying mechanism of polyphyllin D-induced cell death in NB-69 cells is apoptosis, whereas the cell death of IMR-32 and LA-N-2 cells occurs by necroptosis. We continue research on this topic and look forward the discovery of a new therapeutic agent for neuroblastoma.

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Fewer than 100 patients with partial chromosome 2p trisomy have been reported. Clinical features are variable and depend on the size of the duplicated segment, but generally include psychomotor delay, facial anomalies, congenital heart defect, and other abnormalities. We report a 560.49 kb duplication of chromosome 2p in a 13 month-old male with hydrocephaly, ventricular septal defect, partial agenesis of the corpus callosum, and bilateral Wilms tumor. After discovery of bilateral renal masses at four months of age, the child underwent neoadjuvant chemotherapy followed by right radical nephrectomy that revealed triphasic Wilms' tumor. A needle core biopsy on one of two lesions on the left kidney also revealed Wilms tumor. A partial left nephrectomy revealed focally positive margins that necessitated left flank radiotherapy. The tumor karyotype was 46,XY,t(7;8)(q36;p11)[8]/46,XY [12] while his constitutional karyotype was 46,XY, suggesting that the t(7;8)(q36;p11) was associated with the malignancy. Single nucleotide polymorphism (SNP) chromosome microarray analysis of peripheral blood identified a maternally-inherited 560.49 kb chromosome 2p24.3 duplication that involved four OMIM genes: NBAS, DDX1, MYCNOS, and MYCN. SNP array analysis of the tumor revealed the same 2p24.3 duplication. At present, the now 5-year-old boy continues to do well without clinical or radiographic evidence of recurrent disease. This case is instructive because the child's health insurer initially denied authorization for chromosome microarray analysis (CMA), and it took more than one year before such authorization was finally granted. That initial decision to deny coverage could have had untoward health implications for this child, as the identification of constitutional MYCN duplication necessitated surveillance imaging for a number of pediatric malignancies associated with MYCN overexpression/dysregulation.

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Objective To explore the significance of MYCN gene amplification in children with neuroblastic tumors(NT).Methods The clinicopathological data of 154 cases with NT were reviewed,including general data, classification of pathology,clinical stage and prognosis.MYCN gene amplification was detected by fluorescence in situ hybridization(FISH) and its relationship between pathological characteristics and prognostic significance was analyzed.Results There was 154 cases of NT aged 1 day to 11 years,with a mean age of 26.1 months,and the median age of 20.5 months.Male and female ratio was 1.48 : 1.00.According to International Neuroblastoma Staging System (INSS) ,20 cases were of stage Ⅰ (13.0％) ,23 cases of stage Ⅱ (14.9％) ,43 cases of stage Ⅲ (27.9％) ,64 cases of stage Ⅳ(41.6％) and 4 cases of Ⅳs (2.6％).There were 72 cases(46.8％) with favorable histology,and 82 cases(53.2％) with unfavorable histology.MYCN amplification was found in 20 cases (13.0％) and the signal ratio of MYCN and chromosome 2 (CEP2) was 4.08-43.29.One hundred and thirty-four cases of MYCN non-amplification included MYCN gain in 91 cases(68.0％) ,MYCN negative in 43 cases(32.0％).MYCN expression showed the significant differences in ages, neuroblastoma type, international neuroblastoma pathology classification (INPC), mitosis karyorrhexis index (MKI), and clinical stages (all P ＜ 0.05).No significant difference was found in gender(P ＞ 0.05).Of 20 MYCN amplification cases,4 cases (20.0％) survived and 16 cases (80.0％) died,and the overall survival rate was 20.0％ (4/20 cases) ,with survival time was (17.10 ± 2.24) months;of 134 MYCN non-amplification cases,96 cases (71.6％) survived and 38 cases (28.4％) died, with survival time of (28.71 ± 1.28)months.Survival analysis showed the cases with MYCN amplification had worse prognosis (x2 =19.596, P ＜ 0.05).Conclusions Patients with MYCN amplification had poorer prognosis and lower incidence of MYCN amplification of pediatric NT was found in China.

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Objective To identify the effect of arsenic trioxide (As2O3) on the differentiation and apoptosis of different types of neuroblastoma(NB) cell lines.Methods The cell lines [SK-N-SH,SK-N-BE2,SH-SY5 Y] were induced with different concentrations (0 μmol/L,1 μmol/L,3 μmol/L,5 μ mol/L and 7 μ mol/L) of arsenic trioxide for 24 h,48 h,72 h under the same conditions.The expression of MYCN gene was examined by fluorescence in situ hybridization assay in SK-N-BE2,cell proliferation,cell cycle and cell apoptosis were detected with cell counting kit-8 (CCK-8) assay and flow cytometry.Results 5 μmol/L of As2O3 inhibited the expression of MYCN gene in SK-N-BE2;CCK-8 assay indicated that As2O3 inhibited the proliferation of NB cell in a dose-and time-dependent manner,the cell proliferation was significantly suppressed compared with the low concentration (1 μ mol/L) after treated with As2O3 by 1 μmol/L,3 μmol/L,5 μmol/L and 7 μmol/L in 24 h,48 h and 72 h,SH-SY5Y:24 h(chisq =9.666 7,P ＜ 0.05),48 h (chisq =9.666 7,P ＜ O.05),72 h (chisq =9.512 8,P ＜ 0.05);SK-N-SH,24 h (chisq =10.38,P＜0.054 6),48 h(chisq=8.641 0,P＜0.05),72 h(chisq=9.461 5,P＜0.05);SK-N-BE2:24 h (chisq =8.435 9,P ＜0.05),48 h(chisq =8.641 O,P ＜0.05),72 h(chisq =9.545 5,P ＜0.05);compared with the control group,the As2O3-treated cells showed increased apoptosis percentage,with the percentage of 1.6％ (0 μmol/L),3.8％ (1 μmol/L),6.1％ (3 μmol/L),10.4％ (5 μmol/L),40.2％ (7 μ mol/L);the cell cycle was arrested at G2/M phase,which prevented cell division.Conclusions (1) As2O3 play an important role on the NB cells proliferation,apoptosis which were dose-and time-dependent manner.(2)As2O3 can inhibit the expression of MYCN gene.(3)As2O3 also could block NB cell cycle at S and G2/M,and inhibit the cell nucleus replication and the As2O3 had different induced effect between different types of NB cell.

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Objective To investigate the effects of 13-cis retinoic acid (13-cis RA) in inducing differentiation of 3 types of human neuroblastoma (NB) cells in vitro.Methods The status of MYCN gene amplification of cultured SH-SY5Y,SK-N-SH and SK-N-BE2 cells was detected by fluorescence in situ hybridization.After treatment with different concentrations of 13-cis RA,morphological changes were observed by phase-contrast microscope,and neuron-specific enolase (NSE) concentrations were determined by enzyme linked immunosorbent assay.The cell viability was measured through cell counting kit-8 assay,and the cell apoptosis was assayed with flow cytometry (FCM).Results The morphological changes in differentiation were observed in all 3 types of NB cells after 13-cis RA treatment.MYCN amplification was detected in SK-N-BE2 cells even after 13-cis RA treatment,while the other 2 cell lines were amplification-null.After different concentrations of 13-cis RA treatment,NSE concentration increased with prolonged time,especially for SK-N-BE2 cell(F =27.00,P ＜ 0.000 1).13-cis RA stimulated cell proliferation within 48 hours of treatment,and then inhibited cell growth.FCM indicated that the degree of apoptosis in SH-SY5Y cell was significantly higher after 13-cis RA treatment of 10 μmol/L concentration for continuous 96 h and 120 h as compared to the control group (F =16.21,P =0.011;F =16.04,P =0.016).Cell apoptosis of SK-N-SH cell after 13-cis RA treatment of 1 μ mol/L and 10 μ mol/L concentration for 48 h,were significantly higher than those of the control group (F =15.05,P =0.012;F =31.18,P =0.005);while SK-N-BE2 cell with different concentrations of 13-cis RA(1 μmol/L,5 μmol/L,10 μ mol/L) for 120 h were significantly higher than those of the control group(F =9.05,P =0.030;F =11.38,P =0.028;F =7.88,P =0.041).Conclusions The present study showed that 13-cis RA could induce differentiation of human NB ceils in vitro.It induces cell proliferation within 48 hours of 13-cis RA,and thereafter suppresses cell growth.No improvement was found in MYCN amplification cells with the detection of DNA level after 13-cis RA treatment,which suggests that combined treatment is possibly needed.

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Although the incidence of malignant solid tumors in children is not high,it is one of the major death causes in children.MYCN gene amplification is an independent poor prognosis factor of neuroblastoma.MYCN gene involves in neuroblastoma tumorgenesis and is the major evidence of treatment.MYCN gene amplification could be detected in other children's solid tumor.It is associated with unfavorable medulloblastoma pathology,poor outcome of Wilms' tumor and alveolar rhabdomyosarcomas.This review compares different MYCN gene detection methods,makes a summary about the clinical relationship between MYCN gene and children's solid tumor and investigates the possibility of increasing cure rate of malignant solid tumors through molecular specificity treatment.