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The aim of this study was to investigate the effects of hypoxia-inducible factor-1α (HIF-1α) on the proliferation, migration and invasion of neuroblastoma (NB) cells and the mechanisms involved. We here initially used the real-time polymerase chain reaction (real-time PCR), Western blotting and immunohistochemistry (IHC) to detect the expression of HIF-1α and components of the sonic hedgehog (SHH) signaling pathway in NB cells and human specimens. Subsequently, cell proliferation, migration and invasion were analyzed using the cell counting assay, wound healing assay and Transwell system in two types of human NB cell lines, SH-SY5Y and IMR32. In addition, the role of HIF-1α in NB cells growth was determined in a xenograft nude mouse model. We found that the level of HIF-1α was significantly upregulated during NB progression and was associated with the expression of two components of SHH signaling, SHH and GLI1. We next indicated that the proliferation, migration and invasiveness of SH-SY5Y and IMR32 cells were significantly inhibited by HIF-1α knockdown, which was mediated by small interfering RNAs (siRNAs) targeting against its mRNA. Furthermore, the growth of NB cells in vivo was also suppressed by HIF-1α inhibition. Finally, the pro-migration and proliferative effects of HIF-1α could be reversed by disrupting SHH signaling. In conclusion, our results demonstrated that upregulation of HIF-1α in NB promotes proliferation, migration and invasiveness via SHH signaling. [ABSTRACT FROM AUTHOR]

Hirschsprung disease (HSCR) is the most frequent genetic cause of congenital intestinal obstruction with an incidence of 1:5000 live births. In a pathway-based epistasis analysis of data generated by genome-wide association study on HSCR, specific genotype of Patched 1 (PTCH1) has been linked to an increased risk for HSCR. The aim of the present study is to examine the contribution of genetic variants in PTCH1 to the susceptibility to HSCR in Han Chinese. Accordingly, we assessed 8 single nucleotide polymorphisms (SNPs) within PTCH1 gene in 104 subjects with sporadic HSCR and 151 normal controls of Han Chinese origin by the Sequenom MassArray technology (iPLEX GOLD). Two of the eight genetic markers were found to be significantly associated with Hirschsprung disease (rs357565, allele P = 0.005; rs2236405, allele P = 0.002, genotype P = 0.003). Both the C allele of rs357565 and the A allele of rs2236405 served as risk factors for HSCR. During haplotype analysis, one seven-SNP-based haplotype was the most significant, giving a global P = 0.0036. Our results firstly suggest common variations of PTCH1 may be involved in the altered risk for HSCR in the Han Chinese population, providing potential molecular markers for early diagnosis of Hirschsprung disease. [ABSTRACT FROM AUTHOR]

Hirschsprung disease (HSCR) is the most frequent genetic cause of congenital intestinal obstruction with an incidence of 1:5000 live births. In a pathway-based epistasis analysis of data generated by genome-wide association study on HSCR, specific genotype of Patched 1 (PTCH1) has been linked to an increased risk for HSCR. The aim of the present study is to examine the contribution of genetic variants in PTCH1 to the susceptibility to HSCR in Han Chinese. Accordingly, we assessed 8 single nucleotide polymorphisms (SNPs) within PTCH1 gene in 104 subjects with sporadic HSCR and 151 normal controls of Han Chinese origin by the Sequenom MassArray technology (iPLEX GOLD). Two of the eight genetic markers were found to be significantly associated with Hirschsprung disease (rs357565, allele P = 0.005; rs2236405, allele P = 0.002, genotype P = 0.003). Both the C allele of rs357565 and the A allele of rs2236405 served as risk factors for HSCR. During haplotype analysis, one seven-SNP-based haplotype was the most significant, giving a global P = 0.0036. Our results firstly suggest common variations of PTCH1 may be involved in the altered risk for HSCR in the Han Chinese population, providing potential molecular markers for early diagnosis of Hirschsprung disease.

Biliary Atresia (BA), a result from inflammatory destruction of the intrahepatic and extrahepatic bile ducts, is a severe hepatobiliary disorder unique to infancy. Early diagnosis and Kasai operation greatly improve the outcome of BA patients, which encourages the development of early screening methods. Using HPLC coupled tandem mass spectrometry, we detected primary bile acids content in dried blood spots obtained from 8 BA infants, 17 neonatal jaundice and 292 comparison infants at 3-4 days of life. Taurocholate (TC) was significantly elevated in biliary atresia infants (0.98 ± 0.62 µmol/L) compared to neonatal jaundice (0.47 ± 0.30 µmol/L) and comparison infants (0.43 ± 0.40 µmol/L), with p=0.0231 and p=0.0016 respectively. The area under receiver operating characteristic (ROC) curve for TC to discriminate BA and comparison infants was 0.82 (95% confidence interval: 0.72-0.92). A cutoff of 0.63 µmol/L produced a sensitivity of 79.1% and specificity of 62.5%. The concentrations of total bile acids were also raised significantly in BA compared to comparison infants (6.62 ± 3.89 µmol/L vs 3.81 ± 3.06 µmol/L, p=0.0162), with the area under ROC curve of 0.75 (95% confidence interval: 0.61-0.89). No significant difference was found between the bile acids of neonatal jaundice and that of comparison infants. The early increase of bile acids indicates the presentation of BA in the immediate newborn period and the possibility of TC as newborn screening marker.