Huanmin Wang

27-Hydroxycholesterol contributes to disruptive effects on learning and memory by modulating cholesterol metabolism in the rat brain

Cholesterol metabolism is important for neuronal function in the central nervous system (CNS). The oxysterol 27-hydroxycholesterol (27-OHC) is a cholesterol metabolite that crosses the blood-brain barrier (BBB) and may be a useful substitutive marker for neurodegenerative diseases. However, the effects of 27-OHC on learning and memory and the underlying mechanisms are unclear. To determine this mechanism, we investigated learning and memory and cholesterol metabolism in rat brain following the injection of various doses of 27-OHC into the caudal vein. We found that 27-OHC increased cholesterol levels and upregulated the expression of liver X receptor-α (LXR-α) and adenosine triphosphate (ATP)-binding cassette transporter protein family member A1 (ABCA1). In addition, 27-OHC decreased the expression of 3-hydroxy-3-methylglutaryl-CoA reductase (HMG-CR) and low-density lipoprotein receptor (LDLR) in rat brain tissues. These findings suggest that 27-OHC may negatively modulate cognitive effects and cholesterol metabolism in the brain.

Functional Polymorphisms in FAS/FASL System Increase the Risk of Neuroblastoma in Chinese Population

The FAS and FASL system plays a substantial role in apoptosis and immune escape of cells. Three polymorphisms located in the promoter regions of FAS (-1377G/A and -670A/G) and FASL (-844T/C) have been shown to alter the transcriptional activity of the genes, respectively. This study was conducted to evaluate the effects of these polymorphisms on the susceptibility of neuroblastoma in the Chinese population. A total of 203 patients with neuroblastoma and 411 controls were recruited in this case-control study. Polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP) was applied for genotyping. Unconditional logistic regression was used to estimate cancer risk by calculating odds ratios (ORs) and their 95% confidence intervals (95% CIs). It was observed that significantly increased risks of neuroblastoma associated with FAS -1377G/A and FASL -844T/C polymorphisms, with ORs equal to 1.55 (95% CI, 1.10–2.20) for FAS -1377 A allele and 2.90 (95% CI, 2.04–4.12) for FASL -844CC genotype carriers compared with non-carriers, respectively. However, no association was found between the polymorphisms of FAS -670A/G and risk of neuroblastoma. In addition, the cumulative effect of FAS and FASL polymorphisms on risk of neuroblastoma was observed (P for trend = 2.502×10−10), with OR for the carriers of both FAS -1377A allele and FASL -844CC genotypes equaled to 3.95 (95% CI, 2.40–6.51). This work reveals that polymorphisms of FAS -1377G/A and FASL -844T/C but not FAS -670A/G are associated with risk of neuroblastoma in Chinese. These findings support the hypothesis that genetic polymorphism in FAS/FASL death system may influence individual susceptibility to neuroblastoma.

Candidate Gene Association Analysis of Neuroblastoma in Chinese Children Strengthens the Role of LMO1.

Neuroblastoma (NB) is the most common extra-cranial solid tumor in children and the most frequently diagnosed cancer in the first year of life. Previous genome-wide association studies (GWAS) of Caucasian and African populations have shown that common single nucleotide polymorphisms (SNPs) in several genes are associated with the risk of developing NB, while few studies have been performed on Chinese children. Herein, we examined the association between the genetic polymorphisms in candidate genes and the risk of NB in Chinese children. In total, 127 SNPs in nine target genes, revealed by GWAS studies of other ethnic groups and four related lincRNAs, were genotyped in 549 samples (244 NB patients and 305 healthy controls). After adjustment for gender and age, there were 21 SNPs associated with NB risk at the two-sided P < 0.05 level, 11 of which were located in LMO1. After correction for multiple comparisons, only rs204926 in LMO1 remained significantly different between cases and controls (OR = 0.45, 95% CI: 0.31–0.65, adjusted P = 0.003). In addition, 16 haplotypes in four separate genes were significantly different between case and control groups at an unadjusted P value < 0.05, 11 of which were located in LMO1. A major haplotype, ATC, containing rs204926, rs110420, and rs110419, conferred a significant increase in risk for NB (OR = 1.82, 95% CI: 1.41–2.36, adjusted P < 0.001). The major finding of our study was obtained for risk alleles within the LMO1 gene. Our data suggest that genetic variants in LMO1 are associated with increased NB risk in Chinese children.

Correlation between BRAF V600E mutation and clinicopathological features in pediatric papillary thyroid carcinoma

In adults, the presence of the BRAFV600E mutation in papillary thyroid cancer (PTC) has been demonstrated to be strongly associated with aggressive cancer-cell characteristics and poor patient prognosis. In contrast, the frequency of this mutation in pediatric PTC has undergone limited study, and the few available estimates range from 0 to 63%. Furthermore, the role of the BRAFV600E mutation in pediatric PTC is controversial; thus, the present study aimed to investigate the prevalence and role of the BRAFV600E mutation in 48 pediatric patients with PTC, aged 3–13 years. Of these patients, 41 were diagnosed with classic PTC, five were found to have a follicular variant of PTC, and two to exhibit a diffuse sclerosing PTC variant. The BRAFV600E mutation was identified to be present in 35.4% of the 48 analyzed patients, and in 41.5% of the patients diagnosed with classical PTC. Furthermore, the presence of the BRAFV600E mutation was found to be associated with a patient age at diagnosis of less than ten years (P=0.011), the performance of a thyroidectomy (P=0.03), exhibited tumor multifocality (P=0.02) and/or extra-thyroidal invasion (P=0.003), and both a low MACIS (Metastases, Age, Completeness of resection, Invasion, Size)(P=0.036) and AMES (Age, Metastasis, Extent of tumor, Size)(P=0.001) score. Together, these data suggest that the presence of the BRAFV600E mutation may be negatively correlated with partial aggressive clinicopathological features of pediatric PTC.

Maternal smoking during pregnancy and risk of childhood neuroblastoma: Systematic review and meta-analysis

BACKGROUND Prior epidemiological studies suggest a possible association between maternal smoking during pregnancy and risk of childhood neuroblastoma. A meta-analysis was performed statistically surmising all available observational studies on this topic in order to evaluate the potential correlation of maternal smoking during pregnancy and risk of childhood neuroblastoma. METHODS Published literature was obtained from PubMed, Embase, ISI Web of Science, and Cochrane library, and all studies were inclusive until July 2014. Data from epidemiological studies were combined using a general variance-based meta-analytic method employing 95% confidence intervals. The outcome of interest was shown as odds ratio (OR) reflecting the risk of neuroblastoma development associated with smoking while pregnant. Newcastle-Ottawa Scale was used to assess the quality of studies. RESULTS Seven case-control studies meeting protocol specified inclusion criteria were obtained through a comprehensive literature search. These studies enrolled a total of 1909 patients and 15,683 controls. Analysis for homogeneity demonstrated that the data were heterogeneous (P < 0.05) and could be statistically combined with randomized effect model. Combining all seven reports yielded an OR of 1.28 (1.01-1.62), a statistically significant result suggesting possible association between maternal smoking during pregnancy and risk of childhood neuroblastoma development (P = 0.005). There was no association between the dosage of maternal smoking during pregnancy and risk of neuroblastoma. CONCLUSION The available epidemiological data support a possible association between maternal smoking during pregnancy and pediatric neuroblastoma development.

Spinal SHP2 Contributes to Exaggerated Incisional Pain in Adult Rats Subjected to Neonatal and Adult Incisions via PI3K

Neonatal injury-induced exaggeration of pain hypersensitivity after adult trauma is a significant clinical challenge. However, the underlying mechanisms remain poorly understood. Growing evidence shows that spinal Src homology-2 domain-containing protein tyrosine phosphatase-2 (SHP2) contributes to chronic pain in adult rodents. Here we demonstrated that the phosphorylation and expression of SHP2 in synaptosomal fraction of the spinal dorsal horn are elevated in adult rats subjected to neonatal and adult incisions (nIN-IN), and the upregulation of SHP2 is highly correlated with pain hypersensitivity. Intrathecal blockade of SHP2 phosphorylation using a SHP2 protein tyrosine phosphatase inhibitor NSC-87877, or knockdown of SHP2 by intrathecal delivery of small interfering RNA (siRNA), ameliorates mechanical allodynia and heat hyperalgesia in nIN-IN rats. Moreover, the expression of phosphatidylinositol 3-kinase (PI3K) in the spinal dorsal horn is significantly increased in nIN-IN rats. Intrathecal application of PI3K inhibitor, LY294002 or wortmannin, alleviates pain hypersensitivity in nIN-IN rats. Additionally, intrathecal administration of NSC-87877 or SHP2 siRNA attenuates the upregulation of PI3K. Finally, no alternation of SHP2 phosphorylation in the dorsal root ganglion and dorsal root of nIN-IN rats as well as PI3K expression in the dorsal root of nIN-IN rats intrathecally treated with NSC-87877 or SHP2 siRNA is observed. These results suggest that the phosphorylation and expression of SHP2 in the spinal dorsal horn play vital roles in neonatal incision-induced exaggeration of adult incisional pain via PI3K. Thus, SHP2 and PI3K may serve as potential therapeutic targets for exaggerated incisional pain induced by neonatal and adult injuries.

MiR-20a-5p suppresses tumor proliferation by targeting autophagy-related gene 7 in neuroblastoma

BackgroundNeuroblastoma (NB) is the most common malignant tumor originating from the extracranial sympathetic nervous system in children. The molecular mechanisms underlying this disease are complex, and not completely understood.MethodsQuantitative real-time PCR (qRT-PCR) was applied to quantify the expression of miR-20a-5p and its target gene ATG7 in clinical NB tissues. The biological function of miR-20a-5p and ATG7 in SH-SY5Y cells was investigated through in vitro studies (Real-Time cell kinetic analyzer, colony formation assay, caspase-Glo 3/7 assay and western blotting). The luciferase reporter assay was conducted to verify the biological relationship between miR-20a-5p and ATG7.ResultsHere we found that miR-20a-5p expression was significantly downregulated whereas its target autophagy-related gene 7 (ATG7) was increased along with clinical staging of NB progression. Correlation analysis showed that miR-20a-5p had a negative correlation trend with ATG7. In SH-SY5Y cells, forced expression of miR-20a-5p suppressed ATG7 expression, autophagy initiation and cellular proliferation while promoted apoptosis, suggesting a potential association between miR-20a-5p and ATG7. Further bioinformatic target prediction combined with protein expression and luciferase reporter assay verified that miR-20a-5p inhibited ATG7 by directly binding to its 3′-UTR, confirming the involvement of miR-20a-5p in the regulation of ATG7 in NB.ConclusionsThese results clarified that miR-20a-5p inhibited cell proliferation and promoted apoptosis through negative regulation of ATG7 and thus autophagy suppression in SH-SY5Y cells. Therefore, defining the context-specific roles of autophagy in NB and regulatory mechanisms involved will be critical for developing autophagy-targeted therapeutics against NB. Both miR-20a-5p and ATG7 would be potential therapeutic targets for future NB treatment.

Analysis of diagnosis and treatment of lipoblastomatosis

Lipoblastomatosis is a rare benign soft tissue tumor arising from the white fetal-embryonal adipose tissue (Choi et al., 2013). Since the distinction of lipoblastomatosis from lipoblastma was reported by Vellios et al., there are only a few studies, and the incidence rate is approximately 3.5/1,000,000. To analyze the diagnosis and treatment of lipoblastomatosis, 10 diagnosed cases, from January 2006 to December 2015 in Beijing Children’s Hospital, are discussed in the present study. A total of 10 cases include eight boys and two girls (Table S1 in Supporting Information). The children were aged from six months–12 years and one month (average age, two years and three months; median age one year and one month) when diagnosed with lipoblastomatosis. One case presented gastric fistula and intussusceptions postoperative from another hospital. Three cases showed postoperative recurrence in another hospital, and four were recurrence cases in our hospital. All patients exhibited a painless mass, three showed retarded growth and development, one presented lower limb paralysis, fecal incontinence, and bilateral eye asymmetry, whereas one complained about bellyache. The tumors were found in the neck and shoulder, mediastinum, and abdominal wall or cavity. The invasion of multiple critical sites, such as mediastinum and vertebral canal, by the masses, was

γδTFH cells promote B cell maturation and antibody production in neuroblastoma

BackgroundPrevious studies have shown that γδ TFH cells are capable of modulating antibody production in immunized and infected mouse model. In recent studies, human γδ TFH cells are shown to contribute to the activation of humoral immunity and promote the maturation of B cells. However, little information is available on their involvement in neuroblastoma (NB) pathogenesis.ResultsIn the present study, the frequency of γδ TFH cells in 74 NB patients was significantly higher compared with that in 60 healthy controls. Moreover, most γδ TFH cells in NB patients had a naive phenotype with up-regulation of CD25, CD69, HLA-DR and CD40L and down-regulation of ICOS. Importantly, γδ TFH cells in NB patients produced more IL-4 and IL-10 than those in healthy controls. Furthermore, serum total IgG level was significantly increased in NB patients compared with healthy controls. The expression of CD23 on B cells was up-regulated while CD80 expression was significantly down-regulated in NB patients. Further analysis of B cell compartment showed that the frequency of CD19+CD27hi plasma cells was enhanced in NB patients. Spearman’s correlation analysis revealed that the frequency of γδ TFH cells was positively correlated to serum total IgG level and CD19+CD27hi plasma cells in NB patients, but negatively correlated to CD19+ B cells.ConclusionsWe concluded that γδ TFH cells might promote B cell maturation and antibody production in NB patients.