Impaired p53/CEP‐1 is associated with lifespan extension through an age‐related imbalance in the energy metabolism of C. elegans

In the nematode Caenorhabditis elegans, the mammalian tumor suppressor p53 ortholog CEP‐1 mediates the stress response, activates germ line apoptosis and regulates meiotic chromosome segregation. A reduction in its expression, which frequently occurs in mammalian cancer cells, extends lifespan and induces an adaptive response in C. elegans. However, these effects do not involve an increase in oxidative stress resistance. Here, we showed that intermittent exposure to hyperoxia, which induces oxidative stress resistance and lowers the production of ROS derived from mitochondrial respiration in C. elegans, slightly improved the lifespan extension of cep‐1 mutant. Interestingly, ATP levels were increased without an increase in oxygen consumption in cep‐1 mutant during aging. In the wild‐type, lactate levels and consequentially the lactate/pyruvate ratio decreased during aging in adults. Furthermore, the expression levels of mitochondrial respiration‐related sco‐1, which is a target of p53/CEP‐1, as well as those of gluconeogenesis regulation and mammalian sirtuin ortholog genes, were also increased in the aged and adaptive conditioned wild‐type animals. In contrast, the lactate/pyruvate ratio increased in cells of the cep‐1 mutant and was amplified by intermittent hyperoxia. These results suggest that impaired p53/CEP‐1 leads to an imbalance in the age‐related energy metabolic alteration between mitochondrial oxidative phosphorylation and aerobic glycolysis and plays an important role in the extension of both intact and adaptive lifespans.     

Ligand-dependent interaction between estrogen receptor alpha and adenomatous polyposis coli

Numerous independent clinical and experimental studies indicate that estrogens confer a protective effect against development of intestinal tumors, however the molecular mechanisms involved remain unclear. Physiological effects of estrogens are predominantly mediated by the action of nuclear estrogen receptors (ERs). A multifunctional protein adenomatous polyposis coli (APC) is a tumor suppressor and thought to act as a gatekeeper in colon tumorigenesis, as loss of function APC mutations trigger the development of colorectal cancer. Here we report that APC physically associates with ERa in the ligand-dependent manner. We have shown in the endogenous setting that the ligand-activated ERa recruits APC to the promoters in ER target genes and that increased levels of ER-dependent recruitment of APC enhances the ER transactivation through stimulation of histone acetylation. Found in majority of human colon tumors APC truncation mutants lost the ability to interact with ER. Thus, here we present the first evidence of a functional interaction between APC and ER that may be accounted for a tumor protective action of estrogens.     

Expression profiles and functional implications of p53-like transcription factors in thymic epithelial cell subtypes

In this study, we investigated the localization and functional significance of p53 tumor suppressor-like molecules, p63 and p73, in human thymic epithelial cells (TECs). Immunohistochemical studies showed particular distribution profiles of p63 and p73 in thymic epithelium, in which cortical TECs preferentially expressed p63 in their nuclei whereas subcapsular and medullary TECs expressed both p63 and p73 in their nuclei. The wide distribution of p63 in TECs was further suggested by studies using TECs of primary culture. In vitro studies using two human TEC lines demonstrated that p63 was capable of up-regulating intercellular adhesion molecule-1 (ICAM-1) and enhancing the production of IL-6 and IL-8. Moreover, in vitro studies also indicated that p73, but not p63, had the capacity to induce granulocyte macrophage colony stimulating factor (GM-CSF) and granulocyte colony stimulating factor (G-CSF) in the TEC lines. These findings suggest that p63 would regulate the cell adhesive property through ICAM-1/LFA-1 interaction and the production of IL-6 and IL-8, probably in all TEC subtypes. p73 in subcapslar and medullary TECs was suggested to play a role in the regulation of the production of GM-CSF and G-CSF, which might stimulate other stromal cells such as dendritic cells, macrophages and endothelial cells around these regions.     

Evaluation of esophageal function in patients with gastroesophageal reflux disease using transnasal endoscopy

Background and Aims:  To investigate the utility of a new method of carrying out esophageal manometry using a narrow gauge manometry catheter via a transnasal endoscope.
Methods:  The Frequency Scale for the Symptoms of gastroesophageal reflux disease (GERD) (FSSG), a GERD-specific questionnaire, was given to 45 subjects. Subjects 
underwent transnasal endoscopy with three dry and three wet (3 mL water) swallows. Direct observations of the primary peristaltic wave and peristaltic pressure measurement were conducted simultaneously.
Results:  Endoscopic observation of lower esophageal motility associated with swallowing revealed dilatation of the esophageal lumen after swallowing, followed by contraction in association with the primary peristaltic wave. The peristaltic pressure was significantly lower with increased FSSG scores for dry swallows ( r  = −0.347, P  = 0.0212), but no significant correlation was seen for wet swallows.
Conclusions:  The significant negative correlation between reflux symptoms and peristaltic pressure in dry swallows was thought to be that reduced pressure immediately rostral to the lower esophageal sphincter leads to decreased clearance following gastric acid reflux, playing a large part in the onset of symptoms.     

Microphthalmia and lack of vitreous body in transgenic mice expressing the first immunoglobulin-like domain of nectin-1

Background Nectins are Ca²⁺-independent immunoglobulin (Ig)-like cell-cell-adhesion molecules. We have generated transgenic mice expressing a series of soluble forms of nectin-1, and investigated special effects of each soluble form of nectin-1 in vivo. In the course of generating transgenic mice expressing a soluble form of nectin-1 consisting of the first Ig-like domain of nectin-1 and the Fc portion of human IgG1 (PHveC-VhIg), we found that all of the transgenic founder mice showed a microphthalmia. The purpose of this study is to examine functions of the extracellular domains of nectin-1 in eye development using transgenic technology. Methods Eyes of four different transgenic mouse lines expressing each soluble form of nectin-1 were analyzed histologically. Tissue sections were processed with hematoxylin-eosin staining and indirect immunoperoxidase technique. Results All of five transgenic mouse founders expressing PHveC-VhIg, and of three lines expressing PHveC-VpIg made of the first Ig-like domain fused to porcine Fc portions at 5 weeks showed a microphthalmia, but not all of the transgenic mouse lines expressing PHveCIg or PHveCpIg made of the entire ectodomain fused to human or porcine Fc portions. In the abnormal eyes, the vitreous body was almost absent. In PHveC-VhIg-expressing mice at postnatal day 6, each vitreous space was very small. In the neonatal transgenic mice, the vitreous body was almost the same as that of control mice, and PHveC-VhIg was expressed in the optic nerve, conjunctival epithelium, ciliary body, corneal and lens epithelium. At this stage, nectin-1, -3 and -4 were stained in the optic nerve of control mice as well as in that of the transgenic mice. Nectin-1 is faintly stained in the epithelium of the cornea and lens epithelium, but not in the ciliary body. Conclusion Soluble forms of the first Ig-like domain of nectin-1 (PHveC-VhIg and PHveC-VpIg), but not those of the entire ectodomain (PHveCIg and PHveCpIg), lead to microphthalmia and lack of vitreous body in the transgenic mice. Transgenic mice generating group: Keiko Amagai, Minako Kuramochi, Yuki Watanabe and Shigeto Kouda (Sankyo Labo Service Corporation, Tokyo 132-0023, Japan).     

Possible involvement of multidrug-resistance-associated protein (MRP) gene expression in spontaneous drug resistance to vincristine,etoposide and adriamycin in human glioma cells

The multidrug-resistance phenotype in human tumors is partly associated with over-expression of the 170 kDa-P-glycoprotein encoded by the multidrug-resistance-1 (MDRI) gene. Another related, but non-P-glycoprotein, multidrug-resistance-associated protein (MRP) gene encodes a 190 kDa membrane ATP-binding protein. Glioblastoma multiforme is a highly malignant primary neoplasm of the central nervous system which is refractory to anti-cancer chemotherapy, but the mechanism underlying this drug resistance is unknown. Out of glioma cell lines, 2, namely IN500 and T98G, which had elevated MRP mRNA levels, showed the highest resistance to multiple anti-cancer agents such as etoposide, vincristine and adriamycin, and decreased intracellular accumulation of etoposide. In the remaining 5 cell lines, various degrees of sensitivity to adriamycin and etoposide appeared to correlate with their respective MRP mRNA levels. Our study proposes that MRP may be involved in spontaneous multidrug resistance in human gliomas.     

Prenatal Diagnosis in High Risk Pregnancies for Zellweger Syndrome

Zellweger syndrome is a lethal disorder. At present, no effective therapies are known for the patients of Zellweger syndrome. Recently a typical case of Zellweger syndrome in Japan was observed. In spite of intensive care, the patient died at the age of 3 months. Following this, the parents requested prenatal diagnosis for their following two pregnancies.
We investigated levels of very long chain fatty acids (VLCFA), levels of bile acids in amniotic fluid and immunoblotting of peroxisomal β-oxidation enzymes in cultured amniocytes. We report that immunoblotting using cultured amniocytes is an effective method for prenatal diagnosis of Zellweger syndrome. Furthermore, if we use immunoblotting for prenatal diagnosis, we can discriminate pseudoZellweger syndrome from pseudoneonatal adrenoleucodystrophy.
Following prenatal diagnosis, two healthy babies were delivered. After birth, no abnormal levels of VLCFA in either serum or red blood cell membranes were confirmed. In this paper, we report that we can diagnose a healthy fetus in a high risk pregnancy for Zellweger syndrome.     

Epidemiologic Survey of Children with End-Stage Renal Disease

We performed an epidemiologic study on the basis of a questionnaire survey of 162 children with end-stage renal disease (ESRD). Sixty-nine (43%) of our 162 children, including 25 detected at mass screening of urine, were found by chance hematuria and/or proteinuria. The three major causes of ESRD in our children were chronic glomerulonephritis (CGN) in 56, congenital anomalies of the urinary tract in 30, and nephrotic syndrome (NS) in 27. The renal pathology in 39 children with CGN or NS was focal glomerular sclerosis in 15, diffuse mesangial GN in 7, IgA GN in 5, membranoproliferative GN in 3, membranous GN in 3, and unclassified in 6. Forms of dialysis initiated were hemodialysis in 91 children, continuous ambulatory peritoneal dialysis (PD) in 66, and intermittent PD in 5. Renal transplantation was performed on 38 children, and the graft and the patient survival rates were 76% and 89%, respectively. The survival rate of our 162 children for a mean follow-up of 8.1 years was 77%. In conclusion, an integrated program of maintenance dialysis and transplantation provides a favorable life for children with ESRD.     

Treatment for locally advanced esophageal carcinoma complicated by fistulas: Case report

Two cases of advanced esophageal carcinoma complicated by fistula formation, treated with esophageal prostheses followed by chemotherapy or concurrent chemoradiotherapy, are reported. Chemoradiotherapy may be indicated in esophageal carcinoma cases with fistulas if an excellent antitumor response is expected. However, the indication for prosthesis insertion should be limited due to the risk of perforation, which may be a lethal complication.     

Molecular mechanism of tissue-specific actions of SERM

SERM like tamoxifene and raloxifene is a synthetic ligand for estrogen receptor (ER), and exert tissue-specific actions in many target tissues as an agonist/antagonist thorough modifying the ER function. ER is a member of the nuclear steroid/thyroid hormone, fat-soluble vitamin receptor gene superfamily and acts as a ligand-inducible factor. The ligand-dependent transactivation of ER requires direct interactions of co-regulators through its C-terminal helix-12. Ligand binding to ER causes structural alteration with the helix 12 shifting, but such structural alterations appear distinct among the ligand types. Tissue-specific actions of SERM are speculated to exert through ligand-type-specific alterations in structure with consequent recruitments of regulators.