Increased ghrelin signaling prolongs survival in mouse models of human aging through activation of sirtuin1.

Caloric restriction (CR) is known to retard aging and delay functional decline as well as the onset of diseases in most organisms. Ghrelin is secreted from the stomach in response to CR and regulates energy metabolism. We hypothesized that in CR ghrelin has a role in protecting aging-related diseases. We examined the physiological mechanisms underlying the ghrelin system during the aging process in three mouse strains with different genetic and biochemical backgrounds as animal models of accelerated or normal human aging. The elevated plasma ghrelin concentration was observed in both klotho-deficient and senescence-accelerated mouse prone/8 (SAMP8) mice. Ghrelin treatment failed to stimulate appetite and prolong survival in klotho-deficient mice, suggesting the existence of ghrelin resistance in the process of aging. However, ghrelin antagonist hastened death and ghrelin signaling potentiators rikkunshito and atractylodin ameliorated several age-related diseases with decreased microglial activation in the brain and prolonged survival in klotho-deficient, SAMP8 and aged ICR mice. In vitro experiments, the elevated sirtuin1 (SIRT1) activity and protein expression through the cAMP-CREB pathway was observed after ghrelin and ghrelin potentiator treatment in ghrelin receptor 1a-expressing cells and human umbilical vein endothelial cells. Furthermore, rikkunshito increased hypothalamic SIRT1 activity and SIRT1 protein expression of the heart in the all three mouse models of aging. Pericarditis, myocardial calcification and atrophy of myocardial and muscle fiber were improved by treatment with rikkunshito. Ghrelin signaling may represent one of the mechanisms activated by CR, and potentiating ghrelin signaling may be useful to extend health and lifespan.

Human equilibrative nucleoside transporter 1 and Notch3 can predict gemcitabine effects in patients with unresectable pancreatic cancer.

BACKGROUND: Pancreatic ductal carcinoma (PDC) is one of the most lethal human carcinomas. Expression patterns of some genes may predict gemcitabine (GEM) treatment efficacy. We examined predictive indicators of survival in GEM-treated patients by quantifying the expression of several genes in pre-treatment endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) samples from patients with PDC. METHODS: The expressions of human equilibrative nucleoside transporter 1 (hENT1), deoxycitidine kinase, ribonucleoside reductase 1, ribonucleoside reductase 2 and Notch3 in EUS-FNA tissue samples from 71 patients with unresectable PDC were quantified using real-time reverse transcription-polymerase chain reactions and examined for correlations with GEM sensitivity. RESULTS: The log-rank test detected no significant differences in overall survival between GEM-treated patients with low and high mRNA levels of all genes examined. However, low Notch3 mRNA expression was significantly associated with longer overall survival in a multivariate analysis for survival (P=0.0094). High hENT1 expression level was significantly associated with a longer time to progression (P=0.039). Interaction tests for GEM administration and hENT1 or Notch3 mRNA expression were statistically significant (P=0.0054 and 0.0047, respectively). CONCLUSION: hENT1 and Notch3 mRNA expressions in EUS-FNA specimens were the key predictive biomarkers of GEM effect and GEM sensitivity in patients with unresectable PDC.

Clinical impact of cycling the administration of antibiotics for febrile neutropenia in Japanese patients with hematological malignancy.

Despite the availability of newer classes of antibiotics, infection with multi-drug-resistant bacteria is a serious problem. To suppress the appearance of multi-drug-resistant bacteria and to avoid severe infection derived from febrile neutropenia (FN), we conducted cycling the administration of antibiotics for FN in patients with hematological malignancy. The treatment protocol consisted of the administration of four antibiotics each for 3 months in 1 year. The above regimen was repeated for 4 years. A total of 193 patients were registered in the protocol. The mean duration of the administration of cycling antibiotics was 5.9 days (range: 1-16 days). The frequency of FN before the study and during the study was unchanged until the third year, but decreased significantly in the fourth year. The frequency of detection of multi-drug-resistant bacteria in the first year was the same as that before the study was started, but dramatically decreased after the second year. Bacteriological treatment success rates were similar in each trimester and each year. The effective rate was not statistically different in each trimester and each year. We conclude that cycling the administration of antibiotics in patients with FN is useful for suppressing the appearance of multi-drug-resistant bacteria and for obtaining excellent clinical efficacy.

DNA vaccination targeting macrophage migration inhibitory factor prevents murine experimental colitis.

Previous studies have shown that neutralization of macrophage migration inhibitory factor (MIF) by anti-MIF antibody reduces intestinal inflammation in mice. In this study we tested whether or not anti-MIF autoantibody induced by DNA vaccine targeting MIF protects mice against experimental colitis. Mice were administered a MIF-deoxyribonucleic acid (DNA) vaccine by introducing oligonucleotides encoding helper T epitope into the cDNA sequence of murine MIF by in vivo electroporation. Preventive effects of this method against dextran sulphate sodium-induced (DSS) colitis were evaluated. Mice administered with MIF-DNA vaccine raised values of autoantibody significantly. The clinical and histological findings of colitis induced by 3·0% DSS solution were ameliorated significantly in mice treated with MIF-DNA vaccine compared with saline or pCAGGS-treated mice given DSS. Myeloperoxidase activity, infiltration of F4/80-positive staining cells and the levels of proinflammatory cytokines were suppressed in the colon of MIF-DNA vaccine treated mice compared with saline or pCAGGS-treated mice exposed to DSS. Our results suggest that immunization with helper T epitope DNA-vaccine targeting MIF may be a useful approach for the treatment of colitis including inflammatory bowel diseases.

Increased risk of bacterial infection after engraftment in patients treated with allogeneic bone marrow transplantation following reduced-intensity conditioning regimen.

Although bacterial infection is a major cause of death even after reduced-intensity conditioning (RIC) for allogeneic stem cell transplantation (SCT), little is known about the epidemiology and risk factors. The incidence of bacterial infection in 43 patients who received allogeneic bone marrow transplantation (BMT) using a RIC regimen was compared with that in 68 patients who received BMT using a myeloablative conditioning regimen, and risk factors for bacterial infection were identified. Before engraftment, incidences of febrile neutropenia (FN) and documented infections (DI) were significantly decreased in RIC patients (FN: 59.5% vs. 89.6%, P<0.01, DI: 4.8% vs. 17.9%, P<0.01). However, incidence of bacterial infection was significantly increased in RIC patients in the post-engraftment phase (53.8% vs. 11.1%, log-rank, P<0.01). Blood stream was the most frequent focus of infection in both groups. In multivariate analysis, RIC and acute graft-versus-host disease were revealed to be significant risk factors for bacterial infection in this phase. In summary, risk of bacterial infection after engraftment was significantly higher in RIC patients, although infection was decreased before engraftment, and we need to develop a RIC-specific strategy against bacterial infection after RIC SCT.

Effects of preoperative administration of omeprazole on bleeding after endoscopic submucosal dissection: a prospective randomized controlled trial.

BACKGROUND AND AIMS: The effectiveness of preoperative administration of proton pump inhibitors (PPIs) for the prevention of bleeding after endoscopic submucosal dissection (ESD) is unclear. Our aim was to evaluate the benefit of starting PPI treatment 1 day before ESD to prevent bleeding after the procedure. PATIENTS AND METHODS: This was a prospective randomized controlled trial. Data for 155 patients who underwent ESD (preoperative administration group: N = 81; postoperative administration group: N = 74) were analyzed. All patients received standard ESD using an insulation-tipped knife. Patients in the preoperative group were administered omeprazole from the day before ESD, and patients in the postoperative group received omeprazole after ESD. Follow-up endoscopy was performed on day 1, day 7, and day 28. Intragastric pH was measured from samples of gastric juice. The primary endpoint of this study was major bleeding related to ESD, and the secondary endpoint was minor bleeding. RESULTS: Major bleeding occurred in one patient from the postoperative group who had hematemesis. Minor bleeding occurred on day 1 in six patients from the preoperative group and five patients from the postoperative group (7.7 % vs. 7.4 %). There was no significant difference between major and minor bleeding ratios in the two groups. Intragastric pH at ESD in the postoperative group was lower than that in the preoperative group ( P < 0.05). CONCLUSIONS: Preoperative administration of omeprazole offers no additional benefit over postoperative administration alone in the prevention of bleeding after ESD among elderly Japanese people.

Long-term outcome after endoscopic resection in patients with hypopharyngeal carcinoma invading the subepithelium: a case series.

Patients with early stage hypopharyngeal carcinoma can be treated with endoscopic resection. However, strict indication for endoscopic resection in cases of hypopharyngeal carcinoma is unclear. In this paper, we evaluated the long-term outcome after endoscopic resection in patients with hypopharyngeal carcinoma invading the subepithelium. Among 16 patients with hypopharyngeal carcinoma who underwent endoscopic resection, eight patients who were histologically confirmed to have tumors with shallow invasion of the subepithelium were studied. Depth of tumor invasion in the subepithelium in those patients ranged from 300 to 720 microm (mean +/- SD, 490 +/- 140 microm). During a median follow-up period of 40 months, none of the eight patients had local recurrence or metastasis. Kaplan-Meier estimates of relapse-free survival rates at 5 years in the eight patients were 100 %. The results of this study suggest that hypopharyngeal carcinoma with slight invasion to the subepithelium can be successfully treated by endoscopic resection.

Endoscopic retrograde cholangiography versus peroral cholangioscopy to evaluate intraepithelial tumor spread in biliary cancer.

BACKGROUND AND STUDY AIMS: Localized-type bile duct carcinoma (LBDC) is often accompanied by extensive intraepithelial tumor spread (ITS) of 2 cm or more, which makes radical resection more difficult. This retrospective case review compares the diagnostic accuracy of endoscopic retrograde cholangiography (ERC) and peroral cholangioscopy (POCS) to detect ITS beyond the visible LBDC. PATIENTS AND METHODS: Forty-four consecutive patients with LBDC diagnosed between April 2004 and October 2008 who underwent radical resection with histopathological analysis were included in this study. Extensive ITS was found histopathologically in one-third of the cases (32 %). The outcome parameters were the presence or absence of extensive ITS and the extent of extensive ITS proximal and distal to the main tumor. RESULTS: In six cases it was not possible to pass the cholangioscope through the tumor sites. ERC correctly identified the presence of extensive ITS in 11/14 cases and did not yield any false-positive results. The three cases in which ERC was negative were all correctly identified by POCS plus biopsy since the cholangioscope could be passed in all three cases. The extent of extensive ITS was correctly diagnosed by ERC alone, ERC with POCS, and ERC with POCS plus mapping biopsy in 22 %, 77 %, and 100 % of cases, respectively. CONCLUSIONS: The presence of extensive ITS was correctly detected in 80 % of cases by ERC alone. POCS with mapping biopsy provided perfect diagnostic accuracy not only of the presence or absence but also of the extent of extensive ITS. However, POCS has the limitation that the cholangioscope cannot be passed through the tumor sites in approximately 15 % of cases.

Regulation of the expression of MHC class I-related chain A, B (MICA, MICB) via chromatin remodeling and its impact on the susceptibility of leukemic cells to the cytotoxicity of NKG2D-expressing cells.

Innate immune cells such as natural killer (NK) cells play a crucial role in antitumor immune responses. NKG2D is a major activating immunoreceptor expressed in not only NK cells but also CD8+ T cells and shows cytotoxicity against tumors by recognizing its ligands major histocompatibility complex class I-related chain A and B (MICA and MICB) on tumor cells. Recently, it has been suggested that NKG2D-mediated cytotoxicity correlates with the expression levels of NKG2D ligands on target cells. In this study, we were able to increase the expression levels of MICA and MICB on leukemic cell lines and patients' leukemic cells by treatment with trichostatin A (TsA), a histone deacetylase (HDAC) inhibitor. Chromatin immunoprecipitation (ChIP) assays revealed that treatment with TsA resulted in increased acetylation of histone H3 and decreased association with HDAC1 at the promoters of MICA and MICB. Intriguingly, upregulation of MICA and MICB by treatment with TsA led to enhancement of the susceptibility of leukemic cells to the cytotoxicity of NKG2D-expressing cells. Our results suggest that regulation of the expression of NKG2D ligands by treatment with chromatin-remodeling drugs may be an attractive strategy for immunotherapy.

Suppression of tumor growth by intra-muscular transfer of naked DNA encoding adrenomedullin antagonist.

We have recently reported that the intra-tumoral injection of adrenomedullin (AM) antagonist (AMA; AM (22-52)) peptides significantly reduced the in vivo growth of a pancreatic cancer cell line in severely combined immunodeficient (SCID) mice. In the present study, we examined the effects of intra-tumoral and intra-muscular transfers of naked DNA encoding AMA on the in vivo growth of cancer cell lines. We demonstrate that these treatments induce the regression of a pancreatic cancer cell line and a breast cancer cell line inoculated in SCID mice. Furthermore, CD31-positive cells disappear completely from tumor tissues, following treatment, indicating that neo-vascularization is entirely inhibited. These results suggest that the intra-tumoral or intra-muscular transfer of naked DNA encoding AMA might be a promising alternative modality for treating human cancers.

Rabeprazole-based eradication therapy for Helicobacter pylori: a large-scale study in Japan.

BACKGROUND: Large-scale studies of rabeprazole-based Helicobacter pylori eradication therapy have not been reported in Japan. AIMS: To evaluate H. pylori eradication by rabeprazole-based therapy with reference to antibiotic susceptibility, CYP2C19 genotype, and rabeprazole and clarithromycin dosages. METHODS: From 35 centres 479 H. pylori-positive patients with gastric or duodenal ulcer were randomized to four treatment groups: Group 1 (10 mg rabeprazole + 750 mg amoxicillin + 200 mg clarithromycin twice daily for 7 days); Group 2 (10 mg, 750 mg, 400 mg); Group 3 (20 mg, 750 mg, 200 mg) and Group 4 (20 mg, 750 mg, 400 mg). RESULTS: Eradication rates were 86% (102 of 119), 89% (97 of 109), 91% (106 of 116) and 90% (104 of 115) for Groups 1-4, respectively. The eradication rate was 95% (360 of 379) for clarithromycin-susceptible strains, and 50% (30 of 60) for clarithromycin-resistant strains. The eradication rates were 88% (332 of 379) and 96% (77 of 80) in extensive metabolizers and poor metabolizers, respectively. CONCLUSIONS: Rabeprazole-based therapies achieved 50% eradication of clarithromycin-resistant H. pylori, and even achieved good rates in extensive metabolizers. Accordingly, rabeprazole can be recommended as part of a first-line proton pump inhibitor-based triple therapy for H. pylori.

Analysis of donor-type chimerism in lineage-specific cell populations after allogeneic myeloablative and non-myeloablative stem cell transplantation.

We analyzed donor-type chimerism in CD3+, CD14.15+ and CD56+ cells from 36 patients who had undergone conventional-intensity allogeneic stem cell transplantation (CST) and 34 patients who had undergone non-myeloablative allogeneic stem cell transplantation (NST) for hematological malignancies. On day 28 after transplantation, all fractions in NST patients and CD3+ cells in CST patients who received a non-total body irradiation (TBI) regimen showed more frequent mixed chimerism (<90% donor cells) than those in patients who had received TBI. NST patients with acute graft-versus-host disease (grade II-IV) frequently showed more than 50% donor-type chimerism in CD3+ cells on day 14 (P=0.029). NST patients with <50% donor-type chimerism on day 14 and with <90% donor-type chimerism on day 28 in CD56+ cells had significantly poor 1-year overall survival (0 vs 91%, P<0.001 and 20 vs 74%, P=0.002, respectively). Both NST and CST patients with <90% donor-type chimerism in CD14.15+ cells on day 28 had significantly poor 1-year overall survival (14 vs 70%, P=0.005 and 0 vs 66%, P=0.002, respectively). Our data show that the extent of donor-type chimerism in lineage-specific cells appears to have an impact on outcome after allogeneic stem cell transplantation.

Constitutive expression of hypoxia-inducible factor-1alpha renders pancreatic cancer cells resistant to apoptosis induced by hypoxia and nutrient deprivation.

Hypovasculature is an outstanding characteristic of pancreatic cancers in imaging diagnosis, suggesting that blood supply is poor in pancreatic cancer tissues. Despite poor blood supply, pancreatic cancer cells survive and proliferate in severe hypoxia and nutrient deprivation. To demonstrate how pancreatic cancer cells adapt themselves to hypoxia and nutrient deprivation, we investigated the expression of hypoxia-inducible factor 1alpha (HIF-1alpha) protein and HIF-1-inducible genes in human pancreatic cancer cell lines in comparison with other cancer cell lines. We found that HIF-1alpha protein was constitutively expressed in 15 of 20 pancreatic cancer cell lines (75%) but in none of other cancer cell lines tested in this study. The cells with constitutive expression of HIF-1alpha were more resistant to apoptosis induced by hypoxia and glucose deprivation than those without constitutive expression of HIF-1alpha. Transfection with HIF-1alpha transformed the latter cells resistant to apoptosis and increased in vivo tumorigenicity. Furthermore, anaerobic metabolism-associated genes, Glut1 and aldolase A, were more highly expressed in the cells with constitutive expression of HIF-1alpha than in the cells without it. These results suggest that constitutive expression of HIF-1alpha contributes to the survival and proliferation of pancreatic cancer cells in hypoxia and glucose deprivation through the activation of anaerobic metabolism.

Dominant-negative mutations of the tumor suppressor p53 relating to early onset of glioblastoma multiforme.

Previous experiments have suggested that some mutant forms of p53 are able to inactivate the endogenous wild-type p53 protein in a dominant-negative fashion. However, it remains unknown whether tumors with such dominant-negative (transdominant) p53 mutants have a biological significance that is different from that of recessive p53 mutants. In this study, we examined the dominant-negative potential of various p53 mutants using a yeast-based assay in which both wild-type and mutant p53 were efficiently expressed. We tested a total of 106 p53 mutants, which were identified in brain tumors, glioblastoma multiforme-derived cell lines, breast cancers, or premalignant lesions and squamous cell carcinomas of oral epithelium or were otherwise created by mutagenesis. In agreement with the previous studies, our results demonstrated that transdominant mutations affected amino acid residues that are essential for the stabilization of the DNA-binding surface in the p53 core domain and for the direct interaction of p53 with its DNA-binding sequence. Among 40 patients with sporadic glioblastomas, the average age at diagnosis was significantly younger in the patients with tumors harboring dominant-negative mutations (30.4 +/- 14.7 years, n = 7) than it was in those with recessive mutations (55.2 +/- 18.6 years, n = 9, P < 0.012) and in those without mutations (54.7 +/- 17.1 years, n = 24, P < 0.003). Our data suggest that dominant-negative p53 mutants accelerate development and/or growth of glioblastoma anlagen.

Granulocytic differentiation of myeloid progenitor cells by p130, the retinoblastoma tumor suppressor homologue.

The retinoblastoma protein (pRB) and the related pocket proteins, p107 and p130, play crucial roles in mammalian cell cycle control. Recent studies indicate that these pocket proteins are also involved in cellular differentiation processes. We demonstrate in this work that the pRB-related p130 selectively accumulates during the in vitro differentiation of the myeloid progenitor cell, 32Dcl3, into granulocyte in response to granulocyte-colony stimulating factor (G-CSF). This G-CSF-dependent granulocytic differentiation is blocked by the adenovirus E1A oncoprotein, which binds to and inactivates the pRB family of pocket proteins including p130. Furthermore, enforced overexpression of p130 but not pRB inhibits the myeloid cell proliferation that is concomitantly associated with granulocytic differentiation morphologically characterized by nuclear segmentation. However, simple G1-cell cycle arrest induced by cytokine deprivation or ectopic overexpression of the p27 cyclin-dependent kinase inhibitor, or inhibition of E2F activities by dominant negative DP-1 is not sufficient to trigger granulocytic differentiation. The differentiation-promoting activity of p130 in myeloid cells requires both the pocket domain and the spacer domain. Our results indicate that the pRB-related p130 plays a critical role in myeloid cell differentiation and suggest that coupling of cell cycle exit with the cellular differentiation program may be specifically achieved by p130.

A role for Ca2+ in mediating hormone-induced biphasic pepsinogen secretion from the chief cell determined by luminescent and fluorescent probes and X-ray microprobe.

In isolated chief cells from the guinea pig, cholecystokinin (10 nM) and a high concentration of ionomycin each caused a biphasic pattern of pepsinogen secretion. The initial fast response to cholecystokinin was not dependent on medium Ca2+ ans was mimicked by low concentration of ionomycin (100 nM). Inositol 1,4,5-trisphosphate caused a similar fast release from permeabilized cells. The slow component of release was dependent on medium Ca2+, however, and was mimicked by the phorbol ester 12-O-tetradecanoylphorbol 13-acetate (TPA) (100 nM) or the diacylglycerol analogue 1-oleoyl-2-acetylglycerol (OAG) (100 microM). Ionomycin (100 nM) and TPA (and/or OAG), when applied together, reproduced the biphasic pattern of pepsinogen secretion, suggesting that the signalling pathways utilized by both types of agonist contribute to the response evoked by cholecystokinin-hormone stimulation. Both fura-2 and aequorin were used to monitor changes of intracellular Ca2+. Three pathways were found to contribute to the Ca2+ transient. A rapid release of Ca2+ from intracellular store(s), a rapid Ca2+ entry from the extracellular space, and a more sustained Ca2+ entry from the extracellular space. Cholecystokinin induced a rapid increase in cytoplasmic Ca2+ ([Ca2+]i) as estimated with fura-2 and aequorin. This rise was reduced but not abolished upon removal of extracellular Ca2+, suggesting that both Ca2+ entry from the extracellular space and Ca2+ mobilization from the intracellular store(s) contribute to the initial, fast component of the Ca2+ transient. A second, more sustained component of the Ca2+ transient induced by cholecystokinin was abolished by lanthanum. TPA and OAG induced a biphasic Ca2+ transient that could be detected only with aequorin. The late, sustained component of this response was again abolished by lanthanum as well as by removal of extracellular Ca2+. It appears that the late component of the Ca2+ transient is dependent on Ca2+ influx from the extracellular space and is too localized to be detected by fura-2. Prestimulation of cells with TPA or OAG prevented the aequorin transient caused by cholecystokinin and vice versa, suggesting that TPA, OAG and cholecystokinin activate the same pathways of Ca2+ entry into the cytosol from the intracellular store(s) or the extracellular space. The stimulation-sensitive Ca2+ pool was examined with electron probe X-ray microanalysis. It appears to be restricted to an area enriched in secretory granules or peripheral endoplasmic reticulum just beneath the apical plasma membrane and in close association with the microtubular-microfilamentous system.(ABSTRACT TRUNCATED AT 400 WORDS)

Randomized, double-blind, placebo-controlled crossover trial of famotidine in patients with functional dyspepsia.

BACKGROUND: Histamine 2-receptor antagonists were used as a first therapy against functional dyspepsia. However, few clinical studies with famotidine for functional dyspepsia have been reported. AIM: To evaluate the effectiveness of famotidine for functional dyspepsia patients. METHODS: A multicentre, randomized, double-blind, placebo-controlled crossover trail was conducted. Patients diagnosed with functional dyspepsia by the Roma II criteria were included. Subjects were randomized into two groups, and received either famotidine or placebo as the first 4 weeks medication. After a 1-week washout period, they were switched to the other regimen for another 4 weeks. Evaluation was made prior to the start of study, upon completion of the first drug cycle, and the second drug cycle, by Gastrointestinal Symptoms Rating Scale for the seriousness of abdominal symptoms, and by Short Form-36 for the level of quality of life. RESULTS: Nineteen of 21 enrolled patients successfully completed this study. Significant improvement in Gastrointestinal Symptoms Rating Scale scores was observed in abdominal pain (P = 0.007), indigestion and reflux syndrome after famotidine treatment. Also quality of life scores showed significant improvement in body pain, vitality and general health perceptions after famotidine treatment. There was no improvement of symptoms and quality of life scores after administration of placebo. CONCLUSIONS: Famotidine was effective for improving symptoms and quality of life in functional dyspepsia patients.