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Summary Background and Purpose Sprawling ( Swl ) is a radiation‐induced mutation which has been identified to have a nine base pair deletion in dynein heavy chain 1 (DYNC1H1: encoded by a single gene Dync1h1 ). This study is to investigate the phenotype and the underlying mechanism of the Dync1h1 mutant. Methods and Results To display the phenotype of Swl mutant mice, we examined the embryos of homozygous ( Swl/Swl ) and heterozygous ( Swl /+) mice and their postnatal dorsal root ganglion (DRG) of surviving Swl /+ mice. The Swl /+ mice could survive for a normal life span, while Swl/Swl could only survive till embryonic (E) 8.5 days. Excessive apoptosis of Swl/ + DRG neurons was revealed during E11.5–E15.5 days, and the peak rate was at E13.5 days. In vitro study of mutated DRG neurons showed impaired retrograde transport of dynein‐driven nerve growth factor (NGF). Mitochondria, another dynein‐driven cargo, demonstrated much slower retrograde transport velocity in Swl/+ neurons than in wild‐type (WT) neurons. Nevertheless, the Swl , Loa, and Cra mutations did not affect homodimerization of DYNC1H1. Conclusion The Swl/Swl mutation of Dync1h1 gene led to embryonic mal‐development and lethality, whereas the Swl/+ DRG neurons demonstrated deficient retrograde transport in dynein‐driven cargos and excessive apoptosis during mid‐ to late‐developmental stages. The underlying mechanism of the mutation may not be due to impaired homodimerization of DYNC1H1.

c‐Myc induction drives cholestatic liver injury and cholangiocarcinoma (CCA) in mice, and induction of Maf proteins (MafG and c‐Maf) contributes to cholestatic liver injury, whereas S‐adenosylmethionine (SAMe) administration is protective. Here, we determined whether there is interplay between c‐Myc, Maf proteins, and methionine adenosyltransferase α1 (MATα1), which is responsible for SAMe biosynthesis in the liver. We used bile duct ligation (BDL) and lithocholic acid (LCA) treatment in mice as chronic cholestasis models, a murine CCA model, human CCA cell lines KMCH and Huh‐28, human liver cancer HepG2, and human CCA specimens to study gene and protein expression, protein‐protein interactions, molecular mechanisms, and functional outcomes. We found that c‐Myc, MATα1 (encoded by MAT1A), MafG, and c‐Maf interact with one another directly. MAT1A expression fell in hepatocytes and bile duct epithelial cells during chronic cholestasis and in murine and human CCA. The opposite occurred with c‐Myc, MafG, and c‐Maf expression. MATα1 interacts mainly with Mnt in normal liver, but this switches to c‐Maf, MafG, and c‐Myc in cholestatic livers and CCA. Promoter regions of these genes have E‐boxes that are bound by MATα1 and Mnt in normal liver and benign bile duct epithelial cells that switched to c‐Myc, c‐Maf, and MafG in cholestasis and CCA cells. E‐box positively regulates c‐Myc, MafG, and c‐Maf, but it negatively regulates MAT1A. MATα1 represses, whereas c‐Myc, MafG, and c‐Maf enhance, E‐box‐driven promoter activity. Knocking down MAT1A or overexpressing MafG or c‐Maf enhanced CCA growth and invasion in vivo. Conclusion: There is a novel interplay between MATα1, c‐Myc, and Maf proteins, and their deregulation during chronic cholestasis may facilitate CCA oncogenesis. (Hepatology 2016;64:439‐455)

Consensus diagnostic recommendations to distinguish GORD from eosinophilic oesophagitis (EoE) by response to a trial of proton pump inhibitors (PPIs) unexpectedly uncovered an entity called ‘PPI-responsive oesophageal eosinophilia’ (PPI-REE). PPI-REE refers to patients with clinical and histological features of EoE that remit with PPI treatment. Recent and evolving evidence, mostly from adults, shows that patients with PPI-REE and patients with EoE at baseline are clinically, endoscopically and histologically indistinguishable and have a significant overlap in terms of features of Th2 immune-mediated inflammation and gene expression. Furthermore, PPI therapy restores oesophageal mucosal integrity, reduces Th2 inflammation and reverses the abnormal gene expression signature in patients with PPI-REE, similar to the effects of topical steroids in patients with EoE. Additionally, recent series have reported that patients with EoE responsive to diet/topical steroids may also achieve remission on PPI therapy. This mounting evidence supports the concept that PPI-REE represents a continuum of the same immunological mechanisms that underlie EoE. Accordingly, it seems counterintuitive to differentiate PPI-REE from EoE based on a differential response to PPI therapy when their phenotypic, molecular, mechanistic and therapeutic features cannot be reliably distinguished. For patients with symptoms and histological features of EoE, it is reasonable to consider PPI therapy not as a diagnostic test, but as a therapeutic agent. Due to its safety profile, ease of administration and high response rates (up to 50%), PPI can be considered a first-line treatment before diet and topical steroids. The reasons why some patients with EoE respond to PPI, while others do not, remain to be elucidated.

SummaryAimsFibrillar aggregates of β‐amyloid protein (Aβ) are the main constituent of senile plaques and considered to be one of the causative events in the pathogenesis of Alzheimer's disease (AD). Compounds that could inhibit Aβ fibrils formation, disaggregate preformed Aβ fibrils as well as reduce their associated neurotoxicity might have therapeutic values for treating AD. In this study, the inhibitory effects of bis (heptyl)‐cognitin (B7C), a multifunctional dimer derived from tacrine, on aggregation and neurotoxicity of Aβ1‐40 were evaluated both in vitro and in vivo.MethodsThioflavin T fluorescence assay was carried out to evaluate Aβ aggregation, MTT and Hoechst‐staining assays were performed to investigate Aβ‐associated neurotoxicity. Fluorescent probe DCFH‐DA was used to estimate the accumulation of intracellular reactive oxygen stress (ROS). Morris water maze was applied to determine learning and memory deficits induced by intracerebroventricular infusion of Aβ in rats.ResultsB7C (0.1–10 μM), but not tacrine, effectively inhibited Aβ fibrils formation and disaggregated preformed Aβ fibrils following co‐incubation of B7C and Aβ monomers or preformed fibrils, respectively. In addition, B7C markedly reduced Aβ fibrils‐associated neurotoxicity in SH‐SY5Y cell line, as evidenced by the increase in cell survival, the decrease in Hoechst‐stained nuclei and in intracellular ROS. Most encouragingly, B7C (0.1 and 0.2 mg/kg), 10 times more potently than tacrine (1 and 2 mg/kg), inhibited memory impairments after intracerebroventricular infusion of Aβ in rats, as evidenced by the decrease in escape latency and the increase in the spatial bias in Morris water maze test along with upregulation of choline acetyltransferase activity and downregulation of acetylcholinesterase activity.ConclusionThese findings provide not only novel molecular insight into the potential application of B7C in treating AD, but also an effective approach for screening anti‐AD agents.

Lung cancer is one of the most common types of human malignancies and the leading cause of cancer-related death. Patients with surgically resectable early stage lung cancer are more likely curable, but currently only a small population of patients can be diagnosed at such a stage, partly due to our incomplete understanding of the biology of lung cancer and the lack of diagnostic and prognostic biomarkers. Recent studies have shown that NOTCH1 is a critical regulator of human carcinogenesis and has been implicated in multiple steps of cancer development and progression. Herein, we review recent findings about the role of NOTCH1 in lung cancer and discuss its potential usefulness as both a therapeutic target and a biomarker for lung cancer.

Background— Current risk models for predicting long-term mortality after percutaneous coronary intervention are restricted to all-cause mortality. We sought to develop novel risk models for the prediction of cardiac and noncardiac mortality after percutaneous coronary intervention. Methods and Results— We retrospectively evaluated patients who underwent index percutaneous coronary intervention at Mayo Clinic from 2003 to 2008. Long-term deaths were ascertained through scheduled prospective surveillance. Cause of death was determined via telephone interviews, medical records, and autopsy reports. Fine and Gray extension of Cox proportional hazards models was used to model cause-specific cumulative incidence. Candidate variables and interactions were chosen a priori, without variable selection methods. Resulting models were mapped to an integer-based risk score. The study comprised 6636 patients followed up over a median of 62 months (25th, 75th percentiles: 45, 77 months). There were 1488 deaths, 518 (35%) cardiac, 938 (63%) noncardiac, and 32 (2%) unknown. The 5-year predicted cardiac mortality ranged from 0.6% to 97%, with a corrected c -statistic of 0.82. Risk factors for cardiac death included age, body mass index, ejection fraction, and history of congestive heart failure. The integer score for noncardiac death included age, medicine index, body mass index, current smoker, noncardiac Charlson index and cardiac Charlson index, and accommodated significant age-based interactions for smoking and the 2 Charlson indices. Predicted noncardiac mortality at 5 years ranged from 0.2% to 81%, with a corrected c -statistic of 0.77. Conclusions— We report novel risk models to predict cardiac and noncardiac long-term mortality after percutaneous coronary intervention.

AbstractMicroRNA‐200 (miR‐200) has emerged as a regulator of the PI3K/AKT pathway and cancer cell growth. It was reported that miR‐200 can activate PI3K/AKT by targeting FOG2 (friend of GATA 2), which directly binds to the p85α regulatory subunit of PI3K. We found that miR‐200 was elevated in early stage lung adenocarcinomas when compared with normal lung tissues, and the expression of miR‐200 promoted the tumor spheroid growth of lung adenocarcinoma cells. We show that AKT activation was essential for such oncogenic action of miR‐200. However, depletion of FOG2 had little effect on AKT activation. By performing a reverse‐phase protein array, we found that miR‐200 not only activated AKT but also concomitantly inactivated S6K and increased IRS‐1, an S6K substrate that is increased on S6K inactivation. Depletion of IRS‐1 partially inhibited the miR‐200‐dependent AKT activation. Taken together, our results suggest that miR‐200 may activate AKT in lung adenocarcinoma cells through a FOG2‐independent mechanism involving IRS‐1. Our findings also provide evidence that increased miR‐200 expression may contribute to early lung tumorigenesis and that AKT inhibitors may be useful for the treatment of miR‐200‐dependent tumor cell growth. © 2015 IUBMB Life, 67(9):720–725, 2015

The effect of 25-hydroxycholesterol (25-OH-cholesterol) and chenodeoxycholic (CDC) acid on apoprotein secretion, low-density lipoprotein receptor activity, and [3H]triacylglycerol secretion in Hep G2 cells was studied. Both 25-OH-cholesterol and CDC acid increased the secretion of apolipoprotein (apo) E by Hep G2 cells. The secretion of apo A-I was slightly lowered (less than 10% disease). The maximal increase in apo E secretion was observed in culture medium containing 2 micrograms of 25-OH-cholesterol/ml or 10 micrograms of CDC acid/ml plus 10% fetal calf serum. Cholesterol, 7-OH-cholesterol and other bile acids were ineffective in inducing increases in apo E secretion. Another cholesterol synthesis inhibitor, mevinolin, was also ineffective in generating an increase in apoprotein secretion. The data indicated a specific interaction between 25-OH-cholesterol or CDC acid and apo E secretion in Hep G2 cells. Cholesterol synthesis, as measured by the incorporation of [14C]acetic acid into sterols, was repressed in Hep G2 cells in the presence of 25-OH-cholesterol (17% of control value). CDC acid, on the other hand, increased [14C]acetic acid incorporation (156% of control value). The number of LDL receptors in Hep G2 cells was decreased after incubation with 25-OH-cholesterol (62% of control value), but increased significantly after incubation with CDC acid (149% of control value). The secretion of [3H]triacylglycerol by Hep G2 cells incubated with 25-OH-cholesterol was greatly increased (248% of control value). On the contrary, CDC acid did not cause any increase in [3H]triacylglycerol secretion. The above results suggest that 25-OH-cholesterol and CDC acid have different effects on lipid metabolism in Hep G2 cells. The mRNA levels of apo E increased in cells preincubated with 25-OH-cholesterol and CDC acid, which suggested that the increase in apo E secretion is at least partly due to an increase in synthesis.