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Objective: Nonalcoholic steatohepatitis (NASH) is difficult to diagnose in patients with no symptoms. We aimed to investigate the combined effect of farnesoid X receptor (FXR) agonist, obeticholic acid (OCA), and angiotensin II type 1 receptor blocker (ARB: losartan) on an ongoing hepatic fibrosis in a NASH rat model. Methods: Fischer 344 rats were fed with choline-deficient l-amino-acid-defined (CDAA) diet for 16 weeks. After 8-week administration of CDAA diet, OCA, losartan, or a combination of these drugs was administered at a dose of 30 mg/kg/day for 8 weeks by oral gavage. The in vivo and in vitro effects of OCA + losartan and liver fibrosis progression, lipopolysaccharide (LPS), Toll-like receptor 4 (TLR4) regulatory cascade, and gut barrier function were evaluated. Results: OCA + losartan alleviated hepatic fibrosis progression by suppressing α-SMA expression. It inhibited the proliferation of activated hepatic stellate cell (Ac-HSC) and mRNA expression of hepatic transforming growth factor-β1 (TGF-β1), TLR4, and tissue inhibitor of metalloproteinase-1 (TIMP-1) and decreased the hydroxyproline levels. OCA increased the hepatic matrix metalloproteinase-2 (MMP-2) mRNA expression. OCA decreased the mRNA expression of hepatic LPS-binding protein and intestinal permeability by ameliorating the disruption of CDAA diet–induced zonula occludens-1. Losartan directly inhibited the proliferation of Ac-HSC. The in vitro suppressive effects of OCA + losartan on the mRNA expressions of TGF-β1 and α1(I)-procollagen, TLR4, and TIMP-1 in Ac-HSCs were almost in parallel. Conclusions: OCA + losartan suppressed the ongoing hepatic fibrosis by attenuating gut barrier dysfunction and suppressing Ac-HSC proliferation. Combined therapy may be a promising novel approach for NASH with fibrosis. [ABSTRACT FROM AUTHOR]

Background: The CpG island methylator phenotype of neuroblastoma (NBL) is strongly associated with poor prognosis and can be targeted by 5-aza-2'-deoxycytidine (5-aza-dC). Differentiation therapy is a standard maintenance therapy for high-risk NBLs. However, the in vivo effect of tamibarotene, a synthetic retinoic acid, and the efficacy of its combination with 5-aza-dC have not been studied. Here, we conducted a preclinical study to assess the in vivo tamibarotene effect and the combination.Methods: Treatment effects were analysed by in vitro cell growth and differentiation state and by in vivo xenograft suppression. Demethylated genes were analysed by DNA methylation microarrays and geneset enrichment.Results: Tamibarotene monotherapy induced neural extension and upregulation of differentiation markers of NBL cells in vitro, and tumour regression without severe side effects in vivo. 5-Aza-dC monotherapy suppressed tumour growth both in vitro and in vivo, and induced demethylation of genes related to nervous system development and function. Pre-treatment with 5-aza-dC in vitro enhanced upregulation of differentiation markers and genes involved in retinoic acid signaling. Pre-treatment with 5-aza-dC in vivo significantly suppressed tumour growth and reduced the variation in tumour sizes.Conclusions: Epigenetic drug-based differentiation therapy using 5-aza-dC and TBT is a promising strategy for refractory NBLs. [ABSTRACT FROM AUTHOR]

Background: It is widely understood that insulin resistance (IR) critically correlates with the development of liver fibrosis in several types of chronic liver injuries. Several experiments have proved that anti-IR treatment can alleviate liver fibrosis. Sodium-glucose cotransporter 2 (SGLT2) inhibitors comprise a new class of antidiabetic agents that inhibit glucose reabsorption in the renal proximal tubules, improving IR. The aim of this study was to elucidate the effect of an SGLT2 inhibitor on the development of liver fibrosis using obese diabetic Otsuka Long-Evans Tokushima fatty (OLETF) rats and their littermate nondiabetic Long-Evans Tokushima Otsuka (LETO) rats.Methods: Male OLETF and LETO rats were intraperitoneally injected with porcine serum twice a week for 12 weeks to augment liver fibrogenesis. Different concentrations of ipragliflozin (3 and 6 mg/kg) were orally administered during the experimental period. Serological and histological data were examined at the end of the experimental period. The direct effect of ipragliflozin on the proliferation of a human hepatic stellate cell (HSC) line, LX-2, was also evaluated in vitro.Results: OLETF rats, but not LETO rats, received 12 weeks of porcine serum injection to induce severe fibrosis. Treatment with ipragliflozin markedly attenuated the development of liver fibrosis and expression of hepatic fibrosis markers, such as alpha smooth muscle actin, collagen 1A1, and transforming growth factor beta (TGF-β), and improved IR in a dose-dependent manner in OLETF rats. In contrast, the proliferation of LX-2 in vitro was not affected, suggesting that ipragliflozin had no significant direct effect on the proliferation of HSCs.Conclusion: In conclusion, our dataset suggests that an SGLT2 inhibitor could alleviate the development of liver fibrosis by improving IR in naturally diabetic rats. This may provide the basis for creating new therapeutic strategies for chronic liver injuries with IR. [ABSTRACT FROM AUTHOR]

Background: A previous multicenter prospective randomized study from Japan showed that Helicobacter pylori eradication reduced the development of metachronous gastric cancer (MGC) after endoscopic resection for early gastric cancer. MGC risk, however, is not eliminated; yet few studies have evaluated its long-term incidence and risk factors. In this study, we investigated the incidence of and risk factors for MGC in patients who underwent endoscopic resection for early gastric cancer with successful H. pylori eradication. Methods: A total of 594 patients who underwent endoscopic resection for early gastric cancer and successful H. pylori eradication at three institutions (National Cancer Center Hospital, University of Tokyo Hospital, and Wakayama Medical University Hospital) were analyzed retrospectively. Annual endoscopic surveillance was performed after initial endoscopic resection. MGC was defined as a gastric cancer newly detected at least 1 year after successful H. pylori eradication. Results: Ninety-four MGCs were detected in 79 patients during the 4.5-year median follow-up period. Kaplan-Meier analysis showed the cumulative incidence of MGC 5 years after successful H. pylori eradication was 15.0 %; the incidence of MGC calculated by use of the person-year method was 29.9 cases per 1000 person-years. Multivariate analysis using the Cox proportional hazards model revealed that male sex, severe gastric mucosal atrophy, and multiple gastric cancers before successful H. pylori eradication were independent risk factors for MGC. Eleven percent of MGCs (10 of 94) were detected more than 5 years after successful H. pylori eradication. Conclusion: Surveillance endoscopy for MGC in patients who have undergone endoscopic resection for early gastric cancer should be performed even after successful H. pylori eradication. [ABSTRACT FROM AUTHOR]

Hereditary diffuse gastric cancer (HDGC), characterized by susceptibility to gastric signet ring cell carcinomas (SRCCs) and caused by CDH1 germline mutations, is rare in the Japanese. We present here a Japanese family with HDGC identified by comparative genomic hybridization (CGH) analysis. A 55-year-old woman was treated with completion gastrectomy for multiple SRCCs, and pathological examination revealed approximately 200 foci of SRCC with loss of E-cadherin expression. Her 30-year-old son had surveillance endoscopy and was found to have multiple SRCCs. He underwent total gastrectomy, and 32 foci of SRCC with loss of E-cadherin expression were histologically found. Although no point mutations were detected in CDH1 by sequencing, CGH revealed a 275-kb deletion involving exons 7-16 of CDH1 in both patients. While only a few HDGCs have been reported in East Asia, patients with multiple SRCC may need to be offered appropriate genetic counseling and testing in this area. [ABSTRACT FROM AUTHOR]

Background: The KRAS mutation has been associated with resistance to cetuximab, an anti-epidermal growth factor receptor (EGFR) monoclonal antibody, in metastatic colorectal cancer (mCRC). However, the predictive biomarkers of cetuximab resistance in KRAS wild-type mCRC remain unknown except BRAF, NRAS, and PIK3CA exon 20. The objective of the study is to study the impact of EGFR L2 mutations on resistance to cetuximab in KRAS wild-type patients. Patients and methods: A total of 247 mCRC patients were screened for KRAS status at the National Cancer Center Hospital between September 2008 and April 2010. We analyzed the EGFR L2 domain mutation status in KRAS wild type and in the patients treated with cetuximab-based therapy. Results: There were 136 patients with wild-type KRAS (55 %). Sixty-five patients were analyzed for the L2 domain mutation status, and all patients received cetuximab-based therapy. One patient who had a mutation at exon 9 showed a partial response to cetuximab plus irinotecan. Conclusion: Mutation of the EGFR L2 domain was analyzed in mCRC patients. Our findings do not provide sufficient evidence that EGFR L2 domain mutation is correlated with resistance to cetuximab. [ABSTRACT FROM AUTHOR]

Clinical applications of aberrant DNA methylation to cancer diagnostics and therapeutics are accelerating. Especially, the CpG island methylator phenotype (CIMP), simultaneous methylation of multiple genes, provides information that cannot be obtained by other diagnostic methods and therapeutic opportunities. CIMP is known to be associated with poor or good prognosis depending upon cancer types. We identified that CIMP in neuroblastomas (NBLs) is strongly associated with poor prognosis in Japanese NBL cases (hazard ratio (HR)=22). Almost all NBLs with MYCN amplification displayed CIMP, and even among NBLs without MYCN amplification, NBLs with CIMP had worse prognosis (HR=12). The prognostic power was faithfully reproduced in German NBL cases by the same methods, and also in Italian and Swedish NBL cases with different analytical methods. Mechanistically, methylation silencing of different sets of tumor-suppressor genes is involved in poor prognosis of NBLs with CIMP, and the presence of CIMP is most sensitively detected by methylation of the PCDHB family. For therapeutic purposes, a combination of 5-aza-2′-deoxycytidine, a DNA-demethylating drug, with 13-cis-retinoic acid, a differentiating drug, has been shown to be effective for NBLs in vitro, and further development of a better combination(s) is awaited. Now, epigenetic diagnosis and therapeutics are becoming or have become an important choice for cancer patients. [ABSTRACT FROM AUTHOR]

Background: Epigenomic damage induced by Helicobacter pylori infection is accumulated in gastric mucosae before the development of malignancy. In individuals without current H. pylori infection, DNA methylation levels of specific CpG islands (CGIs) are associated with gastric cancer risk. Because risk estimation in individuals with past infection is clinically important, we here aimed to identify the risk markers that reflect epigenomic damage induced by H. pylori infection, and that are informative in these individuals. Methods: Gastric mucosae were obtained from 55 gastric cancer patients (GC-Pt) (21 with current infection and 34 with past infection) and 55 healthy volunteers (HV) (7 never-infected, 21 with current infection, and 27 with past infection). Hypermethylated CGIs were searched for by methylated DNA immunoprecipitation-CGI microarray, and methylation levels were analyzed by quantitative methylation-specific polymerase chain reaction (PCR). Results: By microarray analysis of a pool of three samples from GC-Pt with past infection and another pool of samples from HV with past infection, 15 hypermethylated CGIs in the former pool were isolated. Seven of them had significantly higher methylation levels in GC-Pt with past infection ( n = 10) than in HV with past infection ( n = 10) ( P < 0.001). In a validation cohort (21 GC-Pt with past infection and 14 HV with past infection), the seven new markers had large areas under the receiver-operating characteristic curves (0.78–0.84) and high odds ratios (12.7–36.0) compared with two currently available markers (0.60–0.65, 5.0–5.7). Conclusions: We identified seven novel gastric cancer risk markers that are highly informative in individuals with past infection. [ABSTRACT FROM AUTHOR]

Aberrant CpG methylations play important roles in cancer development and progression. In this study, aberrant methylations in human breast cancer were searched for using methylation-sensitive representational difference analysis (MS-RDA). A CpG island (CGI) in the 5′ region of the heparan sulfate D-glucosaminyl 3-O-sulfotransferase-2 (3-OST-2) gene was found to be hypermethylated, while its exon 2 was hypomethylated. In seven breast cancer cell lines, hypermethylation of the 5′ region and loss of 3-OST-2 expression were observed. Treatment with a demethylating agent, 5-aza-2′-deoxycytidine, removed the methylation of the CGI in the 5′ region and restored its expression, demonstrating silencing of the 3-OST-2 gene. Methylation-specific PCR (MSP) analysis in 85 primary breast cancers showed that the hypermethylation of the CGI in the 5′ region was present in 75 (88%) of them. Quantitative reverse transcriptase-PCR (RT–PCR) analysis in 37 primary breast cancers showed that the average expression level was decreased in them. Further, MSP analysis in primary colon, lung and pancreatic cancers showed that hypermethylation of the CGI in the 5′ region was present in the colon (8/10, 80%), lung (7/10, 70%) and pancreatic (10/10, 100%) cancers. These results showed that silencing of 3-OST-2 was present in a wide range of human cancers. The 3-OST-2 gene encodes an enzyme involved in the final modification step of heparan sulfate proteoglycans (HSPGs), and its silencing is expected to result in abnormal modification of HSPGs and abnormal signal transduction. From the high incidence, silencing of the 3-OST-2 gene is expected to have high diagnostic, and potentially therapeutic, values.Oncogene (2003) 22, 274–280. doi:10.1038/sj.onc.1206146 [ABSTRACT FROM AUTHOR]

An inductively coupled plasma is extracted into a quartz vacuum chamber through an orifice to observe optical characteristics of the extracted afterglow. The Mach disk, the barrel shock and the zone of silence, which are familiar in supersonic molecular beam experiments with neutral gases, are clearly observed. Axial profiles of the emission of various lines are measured with a photodiode array spectrometer. Intensities of ionic lines as well as atomic lines are stronger at the Mach disk than in the zone of silence. The location of the Mach disk with varying chamber presure is in conformity with an experimental equation obtained in supersonic molecular beam experiments. [ABSTRACT FROM AUTHOR]