Hepatitis C virus nonstructural protein 4B induces lipogenesis via the Hippo pathway.

Hepatitis C virus (HCV) infection causes abnormal lipid metabolism in hepatocytes, which leads to hepatic steatosis and even hepatocellular carcinoma. HCV nonstructural protein 4B (NS4B) has been reported to induce lipogenesis, but the underlying mechanism is unclear. In this study, western blots were performed to investigate the effect of NS4B protein levels on key effectors of the Hippo and AKT signaling pathways. Yes-associated protein (YAP) and moesin-ezrin-radixin-like protein (Merlin) are effectors of the Hippo pathway. NS4B downregulated Merlin and phosphorylated YAP (p-YAP) protein expression while increasing the expression of the key AKT pathway proteins p-AKT and NF-κB. By observing the levels of AKT pathway proteins when Merlin was overexpressed or silenced, it was determined that Merlin mediates the AKT pathway. We suggest that HCV NS4B may mediate the AKT signaling pathway by inhibiting the Hippo pathway. Lipid droplets were observed in Huh7.5 cells overexpressing NS4B, and they increased significantly in number when Merlin was silenced. Overexpression of NS4B and Merlin silencing enhanced the expression of sterol regulatory element binding proteins (SREBPs), which have been demonstrated to be key regulatory factors controlling fatty acid synthesis. NS4B and Merlin silencing also enhanced the in vitro proliferative capacity of hepatocellular carcinoma cells. In conclusion, NS4B induces lipogenesis via the effect of the Hippo-YAP pathway on the AKT signaling pathway and thereby plays a significant role in the pathogenesis of HCV-associated diseases.

[Combined G-banded karyotyping and multiplex ligation-dependent probe amplification for the detection of chromosomal abnormalities in fetuses with congenital heart defects].

OBJECTIVE: To assess the value of G-banded karyotyping in combination with multiplex ligation-dependent probe amplification (MLPA) as a tool for the detection of chromosomal abnormalities in fetuses with congenital heart defects. METHODS: The combined method was used to analyze 104 fetuses with heart malformations identified by ultrasonography. Abnormal findings were confirmed with chromosomal microarray analysis (CMA). RESULTS: Nineteen (18%) fetuses were found to harbor chromosomal aberrations by G-banded karyotyping and MLPA. For 93 cases, CMA has detected abnormalities in 14 cases including 10 pathogenic copy number variations (CNVs) and 4 CNVs of uncertain significance (VOUS). MLPA was able to detect all of the pathogenic CNVs and 1 VOUS CNV. CONCLUSION: Combined use of G-banded karyotyping and MLPA is a rapid, low-cost and effective method to detect chromosomal abnormalities in fetuses with various heart malformations.

Novel 12 Mb interstitial deletion of chromosome 8p11.22-p21.2: a case report.

BACKGROUND: The deletion of a short arm fragment on chromosome 8 is a rare cause of Kallmann syndrome and spherocytosis due to deletion of the FGFR1 and ANK1 genes. CASE PRESENTATION: This case study describes a 4-month-old child with growth and psychomotor retardation, auricle deformity, microcephaly, polydactyly, a heart abnormality, and feeding difficulties. An approximately 12.00 MB deletion was detected in the 8p11.22-p21.2 region of chromosome 8. After sequencing, we found that 65 protein genes had been deleted, including FGFR1, which resulted in Kallmann syndrome. There was no deletion of the ANK1 gene associated with spherocytosis, consistent with the phenotype. CONCLUSION: This patient is a new case of short arm deletion of chromosome 8, resulting in novel and previously unreported clinical features.