Whole exome sequencing identified a novel compound heterozygous variation in COL7A1 gene causing dystrophic epidermolysis bullosa.

Dystrophic epidermolysis bullosa (DEB) is a series of severe genetic conditions affecting skin and nails caused by mutations in the COL7A1 gene. DEB has a strong phenotypic variability. In the present study, we recruited a case with a boy exhibiting typical DEB indication, and performed a clinical, genetic, and experimental investigation, followed by a prenatal diagnosis on their current pregnancy. Whole exome sequencing identified a novel compound heterozygous variation in COL7A1, consisting of two variants, namely c.191T>C (p.Leu64Pro) and c.5124G>A (p.Leu1708=) in the proband. In vitro study by minigene system indicated that c.5124G>A would result in an increased ratio of a transcript with exon-skipping, which supported its pathogenicity. Further prenatal detection confirmed the genotype-phenotye co-separation in this family. In conclusion, the findings in our study expanded the mutation spectrum of DEB, and emphasized the importance of paying attention to specific synonymous variants in the filtering process.

Whole Exome Sequencing Facilitated the Identification of a Mosaic Small Supernumerary Marker Chromosome (sSMC).

Small supernumerary marker chromosomes (sSMCs) are a group of rare chromosomal anomalies, which pose challenges in the clinical practice of prenatal diagnosis and genetic counseling. This study enrolled an extended family with an underage male patient displaying infantile seizures, intellectual disability, and retarded speech and psychomotor function. A series of multiplatform genetic detections was conducted to explore the diagnostic variation. Whole exome sequencing (WES) and chromosomal microarray analysis (CMA) indicated a mosaic sSMC derived from the pericentromeric region of chromosome 8 in the patient, which was confirmed using cytogenetic methods. The proband and his mother, who carried this mosaic variant, exhibited strong phenotypic variability. We also ruled out the pathogenicity of a KDM5C variant by extended validation. Our results emphasized the capacity of WES to detect mosaic SMCs and the importance of mosaic ratios in the appearance and severity of symptomatic phenotypes.

Protein expression under sustained activation of signal transducer and activator of transcription-3 in diethylnitrosamine-induced rat liver carcinogenesis.

The aim of the present study was to investigate the expression of proteins associated with the sustained activation of the signal transducer and activator of transcription (STAT)-3 pathway during diethylnitrosamine (DEN)-induced rat liver carcinogenesis. DEN was intermittently administered to rats to induce liver cancer, and light and electron microscopy were used to observe the morphological changes in the liver during carcinogenesis. Western blotting and quantitative polymerase chain reaction (qPCR) were used to detect the expression of STAT-3, phosphorylated (p)-STAT-3, matrix metalloproteinase (MMP)-10, vascular endothelial growth factor (VEGF), kinase insert domain receptor (KDR), hypoxia inducible factor (HIF)-1α, basic fibroblast growth factor (bFGF) and interleukin (IL)-10, in order to investigate the association between STAT-3 and p-STAT-3 expression and MMP-10, VEGF, KDR, HIF-1α, bFGF and IL-10. The western blotting and qPCR results revealed that the expression of STAT-3, p-STAT-3, MMP-10, VEGF, KDR, HIF-1α, bFGF and IL-10 proteins gradually increased during carcinogenesis. Furthermore, the STAT-3 and p-STAT-3 levels were found to positively correlate with MMP-10, VEGF, KDR, HIF-1α, bFGF and IL-10 protein expression. During DEN-induced rat liver carcinogenesis, STAT-3 protein continually activated MMP-10, VEGF, KDR, HIF-1α, bFGF and IL-10, and its expression was found to positively correlate with the expression of these proteins.

Endoplasmic reticulum stress in diethylnitrosamine-induced rat liver cancer.

To analyze the significance of endoplasmic reticulum stress (ERS) in the development of diethylnitrosamine (DEN)-induced liver cancer in rats, critical regulatory factors in ERS signaling pathways were investigated in the present study. The results showed that the expression of ERS-related proteins gradually increased in the early and mid-term stages of carcinogenesis, while in the later stages, the expression of these proteins did not change significantly after reaching a peak. ERS is involved in DEN-induced rat liver injury, the proliferation of liver cells and the occurrence and development of liver cirrhosis. However, ERS did not affect hepatoma cell growth following the formation of rat liver cancer in the current study.

Inhibition of tumor angiogenesis by TTF1 from extract of herbal medicine.

AIM: To study the inhibition of tumor angiogenesis by 5,2,4´-trihydroxy-6,7,5´-trimethoxyflavone (TTF1) isolated from an extract of herbal medicine Sorbaria sorbifolia. METHODS: Angiogenic activity was assayed using the chick embryo chorioallantoic membrane (CAM) method. Microvessel density (MVD) was determined by staining tissue sections immunohistochemically for CD34 using the Weidner capillary counting method. The mRNA and protein levels of vascular endothelial growth factor (VEGF), vascular endothelialgrowth factor receptor 2 (VEGFR2, Flk-1/KDR), basic fibroblast growth factor (bFGF), cyclo-oxygenase (COX)-2 and hypoxia-inducible factor (HIF)-1α were detected by quantitative real-time polymerase chain reaction and Western blotting analysis. RESULTS: The TTF1 inhibition rates for CAM were 30.8%, 38.2% and 47.5% with treatment concentrations of 25, 50 and 100 µg/embryo × 5 d, respectively. The inhibitory rates for tumor size were 43.8%, 49.4% and 59.6% at TTF1 treatment concentrations of 5, 10, and 20 µmol/kg, respectively. The average MVD was 14.2, 11.2 and 8.5 at treatment concentrations of 5 µmol/kg, 10 µmol/kg and 20 µmol/kg TTF1, respectively. The mRNA and protein levels of VEGF, KDR, bFGF, COX-2 and HIF-1α in mice treated with TTF1 were significantly decreased. CONCLUSION: TTF1 can inhibit tumor angiogenesis, and the mechanism may be associated with the down-regulation of VEGF, KDR, bFGF, HIF-1α and COX-2.