Role of AHR, NF-kB and CYP1A1 crosstalk with the X protein of Hepatitis B virus in hepatocellular carcinoma cells.

In this study, it was aimed to elucidate the interaction between aryl hydrocarbon receptor (AHR), nuclear factor-kappa B (NF-kB), and cytochrome P4501A1 (CYP1A1) with hepatitis B virus X protein (HBX) in a human liver cancer cell line (HepG2) transfected with HBX. First, AHR, NF-kB, and CYP1A1 genes were cloned into the appropriate region of the CheckMate mammalian two-hybrid recipient plasmids using a flexi vector system. Renilla and firefly luciferases were quantified using the dual-luciferase reporter assay system to measure the interactions. Secondly, transient transfections of CYP1A1 and NF-kB (RelA) were performed into HBX-positive and HBX-negative HepG2 cells. The mRNA expression of CYP1A1 and NF-kB genes were confirmed with RT-PCR, and cell viability was measured by WST-1. Further verification was assessed by measuring the activity and protein level of CYP1A1. Additionally, CYP1A1/HBX protein-protein interactions were performed with co-immunoprecipitation, which demonstrated no interaction. These results have clearly shown that the NF-kB and AHR genes interact with HBX without involving CYP1A1 and HBX protein-protein interactions. The present study confirms that AHR and NF-kB interaction plays a role in the HBV mechanism mediated via HBX and coordinating the carcinogenic or inflammatory responses; still, the CYP1A1 gene has no effect on this interaction.

Health information technology adoption and acceptance of Turkish physicians-A model proposal and empirical assessment.

Health Information Technology (HIT) systems are receiving increasing attention in recent years. Yet, individual adoption research in health care settings, especially in developing countries are quite limited. Moreover, large body of Information Systems research has focused on user perceptions to form intentions to use a particular technology. However, the antecedents and consequences of perceptions remained largely unanswered in existing research. This study aims to fill this gap by proposing and testing a research model based on a modified Technology Acceptance Model (m - TAM) which incorporates socio psychological and cognitive factors to assess the HIT's adoption level of Turkish physicians. To do so, two different methods were used to collect data from head physicians, assistant head physicians, and physicians: face to face and online survey. Total 212 useful responses were returned. 174 of them were face-to-face surveys which were administrated to all the first level and some second and third level health organizations. The rest of the surveys were administrated to the second and third level healthcare organizations via online participation. Data were analyzed by Structural Equation Modelling via SmartPLS software program. Results present that commitment is a strong predictor of HIT usage, whereas neither motivation nor resistance has a significant impact on HIT usage.

Chemoprotective effect of vitamin E in cyclophosphamide-induced hepatotoxicity in rats.

Cyclophosphamide (CP) has a range of adverse effects on liver tissue in humans and animals. Administering an antioxidant with CP might reduce such side effects. Therefore, we examined the role of vitamin E in CP-induced liver toxicity in rats. Male Wistar albino rats were divided into four groups, each of seven rats: control, CP only, CP + vitamin E, and vitamin E only groups. The rats were administered treatments intraperitoneally for 7 days. Then the serum malondialdehyde (MDA), alanine aminotransferase (ALT), aspartate transaminase (AST), and lactate dehydrogenase (LDH) levels were determined while the livers were removed, tissue was prepared using routine histological procedures, sections were stained using hematoxylin and eosin, and the terminal deoxynucleotidyl transferase-mediated nick end-labeling (TUNEL) method was applied. Histopathologically, CP caused hydropic degeneration, necrosis, pleomorphism, and mitotic activity. The number of TUNEL-positive cells and the MDA and ALT levels were significantly higher in the CP group. The antioxidant effects of vitamin E significantly decreased the number of TUNEL-positive cells and the ALT and MDA levels, and normalized the liver histopathology. CP induces apoptosis, has toxic effects on liver tissue, and changes the histological structure. The administration of vitamin E prevented the liver tissue damage caused by CP.

Valproic acid inhibits the proliferation of SHSY5Y neuroblastoma cancer cells by downregulating URG4/URGCP and CCND1 gene expression.

Valproic acid (VPA), used for the treatment of epilepsy and bipolar disorder, regulates several signaling pathways in brain cells. The up-regulated gene 4 (URG4/URGCP) is a novel gene located on 7p13. URG4/URGCP stimulates cyclin D1 (CCND1) mRNA expression, and URG4/URGCP silencing diminishes CCND1 mRNA expression in HepG2 cells. This study was performed to investigate the anti-cancer mechanism of action of VPA by analyzing the expression of novel gene URG4/URGCP, CCND1, p21, p53, p65 (RelA), Bax, and Bcl-2 in SHSY5Y neuroblastoma (NB) cancer cells. Cytotoxic effects of VPA in SHSY5Y were noticed in time and dose dependent manner with the IC50 doses within the range of 0.5-10 mM. IC50 doses in the SHSY5Y were detected as 7.5 mM. Expression profiles were determined by semi quantitative RT-PCR and URG4/URGCP protein change by western blot analysis. Our results suggest that VPA induces cell cycle arrest in SHSY5Y due to the decrease in URG4/URGCP, CCND1 gene expression and the increase in p65. To conclude, VPA may be a prospective agent for the treatment of NB as a single agent or in combination with other drugs. Thus, more studies should be designed to find a safe dose with the best effects of VPA.

Expression of URG4/URGCP, Cyclin D1, Bcl-2, and Bax genes in retinoic acid treated SH-SY5Y human neuroblastoma cells.

Retinoic acid (RA) plays important roles in development, growth, and differentiation by regulating the expression of its target genes. The pro-apoptotic Bax gene may form channels through oligomerization in the mitochondrial membrane and facilitate the cytosolic release of cytochrome c. The anti-apoptotic Bcl-2 gene can inhibit this process. Up-regulated gene 4/Upregulator of cell proliferation (URG4/URGCP) is a novel gene located on 7p13. URG4/URGCP also stimulates cyclin D1 (CCND1) mRNA expression, and RNAi-mediated URG4/URGCP silencing diminishes CCND1 mRNA expression in HepG2 cells. In this study, the effects of RA treatment on URG4/URGCP, CCND1, Bcl-2 and Bax gene expression changes in undifferentiated and differentiated SHSY5Y neuroblastoma cells was analyzed. SHSY5Y cells were cultured in the appropriate conditions. To induce differentiation, the cells were treated with 10 micromolar RA in the dark for 3-10 days. SHSY5Y cells possess small processes in an undifferentiated state, and after treatment with RA, the cells developed long neurites, resembling a neuronal phenotype. Total RNA was isolated with Tri-Reagent. Expression profiles of the target genes were determined by semi-quantitative RT-PCR. According to the results, Bcl-2 and CCND1 gene expression levels were increased, while URG4/URGCP and Bax gene expression was decreased in RA treated cells compared to the control cells. Our preliminary results suggest that RA may induce cell proliferation and escape apoptosis using a novel pathway by the URG4/URGCP gene. Further investigations are needed to clarify more direct transcriptional targets of RA signaling and the interaction of RA pathways with other pro-regenerative signals.