Effect of respiratory syncytial virus on the growth of hepatocellular carcinoma cell-lines

In several reports, the respiratory syncytial virus (RSV) was identified as an oncolytic virus in cancer cells (e.g., lung and prostate cancer). However, the effects of RSV in hepatocellular carcinoma (HCC) cells have not yet been investigated. Here, we observed the inhibitory effects of RSV infection in HCC cell-lines. Cell growth was significantly decreased by RSV infection in BNL-HCC, Hep3B, Huh-7 and SNU-739 cells. After RSV infection, plaque formation and syncytial formation were observed in affected Hep3B and Huh-7 cells. RSV protein-expression was also detected in Hep3B and Huh-7 cells; however, only Huh-7 cells showed apoptosis after RSV infection. Furthermore, inhibition of cell migration by RSV infection was observed in BNL-HCC, Hep3B, Huh-7 and SNU-739 cells. Therefore, further investigation is required to clarify the molecular mechanism of RSV-mediated inhibition of HCC cell growth, and to develop potential RSV oncolytic viro-therapeutics. [BMB Reports 2015; 48(10): 565-570]     

DICER1 loss and Alu RNA induce age-related macular degeneration via the NLRP3 inflammasome and MyD88

Alu RNA accumulation due to DICER1 deficiency in the retinal pigmented epithelium (RPE) is implicated in geographic atrophy (GA), an advanced form of age-related macular degeneration that causes blindness in millions of individuals. The mechanism of Alu RNA-induced cytotoxicity is unknown. Here we show that DICER1 deficit or Alu RNA exposure activates the NLRP3 inflammasome and triggers TLR-independent MyD88 signaling via IL18 in the RPE. Genetic or pharmacological inhibition of inflammasome components (NLRP3, Pycard, Caspase-1), MyD88, or IL18 prevents RPE degeneration induced by DICER1 loss or Alu RNA exposure. These findings, coupled with our observation that human GA RPE contains elevated amounts of NLRP3, PYCARD, and IL18 and evidence of increased Caspase-1 and MyD88 activation, provide a rationale for targeting this pathway in GA. Our findings also reveal a function of the inflammasome outside the immune system and an immunomodulatory action of mobile elements.     

The major target of the endogenously generated reactive oxygen species in response to insulin stimulation is phosphatase and tensin homolog and not phosphoinositide-3 kinase (PI-3 kinase) in the PI-3 kinase/Akt pathway

Phosphoinositide-3 kinase (PI-3 kinase) and its downstream signaling molecules PDK-1 and Akt were analyzed in SK-N-SH and SK-N-BE(2) human neuroblastoma cell lines. When cells were stimulated with insulin, PI-3 kinase was activated in both cell lines, whereas the translocation of PDK-1 to the membrane fraction and phosphorylated Akt were observed only in SK-N-SH cells. Analyses of the insulin-mediated reactive oxygen species (ROS) generation and Phosphatase and Tensin homolog (PTEN) oxidation indicate that PTEN oxidation occurred in SK-N-SH cells, which can produce ROS, but not in SK-N-BE(2) cells, which cannot increase ROS in response to insulin stimulation. When SK-N-SH cells were pretreated with the NADPH oxidase inhibitor diphenyleneiodonium chloride before insulin stimulation, insulin-mediated translocation of PDK-1 to the membrane fraction and phosphorylation of Akt were remarkably reduced, whereas PI-3 kinase activity was not changed significantly. These results indicate that not only PI-3 kinase activation but also inhibition of PTEN by ROS is needed to increase cellular level of phosphatidylinositol 3,4,5-trisphosphate for recruiting downstream signaling molecules such as PDK-1 and Akt in insulin-mediated signaling. Moreover, the ROS generated by insulin stimulation mainly contributes to the inactivation of PTEN and not to the activation of PI-3 kinase in the PI-3 kinase/Akt pathway.     

BMI and Metabolic Disorders in South Korean Adults: 1998 Korea National Health and Nutrition Survey

Objective: The prevalence of overweight, obesity, and metabolic disorders and their relationship with BMI were studied in South Korean adults. The appropriate BMI categories for overweight and obesity for Koreans were evaluated. Research Methods and Procedures: The 1998 Korea National Health and Nutrition Examination Survey was the first such survey, to our knowledge, conducted on a cross‐sectional and nationally representative population. The survey provided data on body weight; height; fasting serum glucose; triacylglycerol; total, low‐density lipoprotein, and high‐density lipoprotein cholesterol; blood pressure; and various other questions that were incorporated into this study. A total of 39, 060 persons over the age of 1 year from 12, 283 households participated in the Health and Nutrition Interview Survey. Of these, 10, 876 people over the age of 10 years old participated in the Health Examination. We analyzed data from 7962 adults over the age of 20 years old. Results: The overweight (BMI, ≥25.0 to <30.0) and obesity (BMI, ≥30) rates were low among Korean adults: 23.4% and 1.7% in men and 24.9% and 3.2% in women, respectively. However, the prevalences of diabetes, hypertension, and abnormal concentrations of serum triacylglycerol and total, low‐density lipoprotein, and high‐density lipoprotein cholesterol were high at 10.5%, 27.1%, 29.0%, 34.5%, 28.4%, and 37.4%, respectively. These disorders were age dependent, and, in general, there was a strong linear relationship between BMI and the disorders. The relative risk of disorders doubled at a BMI of 23.0 to 24.0 and tripled at a BMI of 26.0, compared with a baseline BMI of 18.5 to 22.0. Discussion: High rates of diabetes, hypertension, and dyslipidemia were noted in middle‐aged and elderly Koreans even at relatively low BMI. It might be appropriate to lower the BMI classification from the current ≥25.0 for overweight and ≥30.0 for obesity for this group of Koreans.     

1H-Pyrazole-1-carboxamidines: new inhibitors of nitric oxide synthase

1H-Pyrazole-1-carboxamidines were prepared as potential inhibitors of the three isozymes of nitric oxide synthase. All of the compounds were found to be competitive inhibitors of all three isoforms. The most selective compound prepared was 1H-pyrazole-N-(3-aminomethylanilino)-1-carboxamidine (14), which is 100-fold selective for nNOS over eNOS with a K_i value of 2 μM.     

Network Modeling Identifies Molecular Functions Targeted by miR-204 to Suppress Head and Neck Tumor Metastasis

Due to the large number of putative microRNA gene targets predicted by sequence-alignment databases and the relative low accuracy of such predictions which are conducted independently of biological context by design, systematic experimental identification and validation of every functional microRNA target is currently challenging. Consequently, biological studies have yet to identify, on a genome scale, key regulatory networks perturbed by altered microRNA functions in the context of cancer. In this report, we demonstrate for the first time how phenotypic knowledge of inheritable cancer traits and of risk factor loci can be utilized jointly with gene expression analysis to efficiently prioritize deregulated microRNAs for biological characterization. Using this approach we characterize miR-204 as a tumor suppressor microRNA and uncover previously unknown connections between microRNA regulation, network topology, and expression dynamics. Specifically, we validate 18 gene targets of miR-204 that show elevated mRNA expression and are enriched in biological processes associated with tumor progression in squamous cell carcinoma of the head and neck (HNSCC). We further demonstrate the enrichment of bottleneckness, a key molecular network topology, among miR-204 gene targets. Restoration of miR-204 function in HNSCC cell lines inhibits the expression of its functionally related gene targets, leads to the reduced adhesion, migration and invasion in vitro and attenuates experimental lung metastasis in vivo. As importantly, our investigation also provides experimental evidence linking the function of microRNAs that are located in the cancer-associated genomic regions (CAGRs) to the observed predisposition to human cancers. Specifically, we show miR-204 may serve as a tumor suppressor gene at the 9q21.1–22.3 CAGR locus, a well established risk factor locus in head and neck cancers for which tumor suppressor genes have not been identified. This new strategy that integrates expression profiling, genetics and novel computational biology approaches provides for improved efficiency in characterization and modeling of microRNA functions in cancer as compared to the state of art and is applicable to the investigation of microRNA functions in other biological processes and diseases.