The Effect of Nutrients on Subjective Accomplishment at Work: Results from a Health Survey and a Single-Arm Dietary Intervention Study.

In Japan, many workers are exposed to chronic stress, sleep deprivation, and nutritional imbalance. They tend still to go to work when ill, leading to decreased work performance and productivity, which has become a major social problem. We conducted a human entry study with the aim of finding a link between these two factors and proposing an optimized diet, believing that a review of diet may lead to an improvement in labor productivity. In this study, we used subjective accomplishment (SA) as a measure of productivity. First, we compared nutrient intake between groups with high and low SA using data from a health survey of 1564 healthy male and female adults. Significant differences were found in the intake of 13 nutrients in males and 15 nutrients in females, including potassium, vitamin A, insoluble fiber, and biotin. Recommended daily intake of these nutrients was determined from survey data. Next, we designed test meals containing sufficient amounts of 17 nutrients and conducted a single-arm intervention study (registration code UMIN000047054) in Kameyama City, Mie Prefecture, Japan. Healthy working adults (males and females aged 20-79 years) were recruited and supplied with test meals, which were eaten once a day 5 days a week for 8 weeks. SA was significantly higher and daytime sleepiness (DS) was significantly lower after lunch on workdays in younger participants (under 60 years) when they ate the test meals as breakfast or lunch. Our results suggest that SA and DS, which change daily, are strongly influenced by the meal eaten before work, and that taking the 17 nutrients may help prevent presenteeism and improve labor productivity.

Identification of a novel oncogenic mutation of FGFR4 in gastric cancer.

Gastric cancer remains one of the leading causes of cancer death worldwide. Despite intensive investigations of treatments over the past three decades, the poor prognosis of patients with unresectable advanced or recurrent gastric cancer has not significantly changed, and improved therapies are required. Here, we report the identification of an oncogenic mutation in FGFR4 in a human gastric tumour that leads to constitutive activation of its product, FGFR4. The G636C-FGFR4 tyrosine kinase domain mutation was found in 1 of 83 primary human gastric tumours. The G636C mutation increased FGFR4 autophosphorylation, and activated FGFR4 downstream signalling molecules and enhanced anchorage-independent cell growth when expressed in NIH/3T3 cells. 3D-structural analysis and modelling of FGFR4 suggest that G636C destabilizes an auto-inhibitory conformation and stabilizes an active conformation, leading to increased kinase activation. Ba/F3 cell lines expressing the G636C-FGFR4 mutant were significantly more sensitive to ASP5878, a selective FGFR inhibitor, than the control. Oral administration of ASP5878 significantly inhibited the growth of tumours in mice engrafted with G636C-FGFR4/3T3 cells. Together, our results demonstrate that mutationally activated FGFR4 acts as an oncoprotein. These findings support the therapeutic targeting of FGFR4 in gastric cancer.

ASP5878, a Novel Inhibitor of FGFR1, 2, 3, and 4, Inhibits the Growth of FGF19-Expressing Hepatocellular Carcinoma.

Hepatocellular carcinoma is an aggressive cancer with poor prognosis. Fibroblast growth factor 19, a member of the fibroblast growth factor family, is a ligand for fibroblast growth factor receptor 4. Moreover, it plays a crucial role in the progression of hepatocellular carcinoma. ASP5878 is a novel inhibitor of fibroblast growth factor receptors 1, 2, 3, and 4 that is under development. It inhibits fibroblast growth factor receptor 4 kinase activity with an IC50 of 3.5 nmol/L. ASP5878 potently suppressed the growth of the fibroblast growth factor 19-expressing hepatocellular carcinoma cell lines Hep3B2.1-7, HuH-7, and JHH-7. In the Hep3B2.1-7 cell line, ASP5878 inhibited the phosphorylation of fibroblast growth factor receptor 4 and its downstream signaling molecules as well as induced apoptosis. Oral administration of ASP5878 at 3 mg/kg induced sustained tumor regression in a subcutaneous xenograft mouse model using Hep3B2.1-7. In HuH-7, an orthotopic xenograft mouse model, ASP5878 induced complete tumor regression and dramatically extended the survival of the mice. These results suggest that ASP5878 is a potentially effective therapeutic agent for hepatocellular carcinoma patients with tumors expressing fibroblast growth factor 19. Mol Cancer Ther; 16(1); 68-75. ©2016 AACR.

Deregulation of pancreas-specific oxidoreductin ERO1ß in the pathogenesis of diabetes mellitus.

A growing body of evidence has underlined the significance of endoplasmic reticulum (ER) stress in the pathogenesis of diabetes mellitus. ER oxidoreductin 1ß (ERO1ß) is a pancreas-specific disulfide oxidase that is known to be upregulated in response to ER stress and to promote protein folding in pancreatic ß cells. It has recently been demonstrated that ERO1ß promotes insulin biogenesis in ß cells and thus contributes to physiological glucose homeostasis, though it is unknown if ERO1ß is involved in the pathogenesis of diabetes mellitus. Here we show that in diabetic model mice, ERO1ß expression is paradoxically decreased in ß cells despite the indications of increased ER stress. However, overexpression of ERO1ß in ß cells led to the upregulation of unfolded protein response genes and markedly enlarged ER lumens, indicating that ERO1ß overexpression caused ER stress in the ß cells. Insulin contents were decreased in the ß cells that overexpressed ERO1ß, leading to impaired insulin secretion in response to glucose stimulation. These data indicate the importance of the fine-tuning of the ER redox state, the disturbance of which would compromise the function of ß cells in insulin synthesis and thus contribute to the pathogenesis of diabetes mellitus.

Identification of a network involved in thapsigargin-induced apoptosis using a library of small interfering RNA expression vectors.

We describe here the construction of a library of small interfering RNA expression vectors targeted to a few hundred apoptosis-related genes and the application of this library to an investigation of thapsigargin (TG)-induced apoptosis. Thapsigargin triggers endoplasmic reticulum stress, with subsequent apoptosis, but the molecular mechanisms underlying this process are incompletely understood. Using our library, we identified three anti-apoptotic genes, namely, NOXA, E2F1, and MAPK1, in addition to already characterized genes in the apoptotic pathway. In contrast to proposals by others, our data revealed (i) that TG-induced apoptosis is associated with Apaf1 in a caspase-3- and caspase-9-independent manner; (ii) that the E2F1-PUMA pathway might be involved; and (iii) that the ERK pathway, via MAP3K8 (mitogen-activated protein kinase kinase 8), is required for the induction by TG of apoptosis. Our study demonstrates clearly that unexpected and novel genes can be identified effectively by our method, and it provides evidence for the efficacy and utility of the comprehensive analysis of signaling networks and pathways using a library of small interfering RNA expression vectors.

Stimulatory effect of an indirectly attached RNA helicase-recruiting sequence on the suppression of gene expression by antisense oligonucleotides.

Antisense oligonucleotides (ODNs) are powerful tools with which to determine the consequences of the reduced expression of a selected target gene, and they may have important therapeutic applications. Methods for predicting optimum antisense sites are not always effective because various factors, such as RNA-binding proteins, influence the secondary and tertiary structures of RNAs in vivo. To overcome this obstacle, we have attempted to engineer an antisense system that can unravel secondary and tertiary RNA structures. To create such an antisense system, we connected the constitutive transport element (CTE), an RNA motif that has the ability to interact with intracellular RNA helicases, to an antisense sequence so that helicase-binding hybrid antisense ODN would be produced in cells. We postulated that this modification would enhance antisense activity in vivo, with more frequent hybridization of the antisense ODN with its targeting site. Western blotting analysis demonstrated that a hybrid antisense ODN targeted to the bcl-2 gene suppressed the expression of this gene more effectively than did the antisense ODN alone. Our results suggest that the effects of antisense ODNs can be enhanced when their actions are combined with those of RNA helicases.

Induction of apoptosis in HeLa cells with siRNA expression vector targeted against bcl-2.

RNA interference (RNAi) is the process by which double-stranded RNA (dsRNA) directs sequence-specific gene silencing in animal and plant cells. In mammalian cells, 21- or 22-nucleotide (nt) RNAs with 2-nt 3' overhangs small inhibitory RNAs (siRNAs) exhibit an RNAi effect. Very recently, we and others have developed a vector-based siRNA expression system that can induce RNAi in mammalian cells. In this report, to apply this system to oncogene therapy, we tried to suppress the expression of the bcl-2 gene, which is known as a key molecule in the regulation of apoptosis or programmed cell death, by using the siRNA expression system. Western blotting analysis revealed that this siRNA expression vector against bcl-2 suppressed the expression of the bcl-2 protein. Furthermore, HeLa cells which were transiently transfected with the siRNA expression vector against bcl-2 and were subsequently treated with doxorubicin efficiently underwent apoptosis, concomitant with the repression of the bcl-2 gene. These results demonstrate that the siRNA expression vector against bcl-2 has a potential as therapeutic agent for a variety of cancers by down-regulating bcl-2 gene expression.