Inhibitory effects of rapamycin on the different stages of hepatic fibrosis.

Aim: To investigate and compare the inhibitory effects of rapamycin in the different stages of liver fibrosis.

Methods: We performed bile duct ligation (BDL) in male Wistar rats (n = 24). The experimental rats were classified into four groups: the BDL(+)/Rapa(-) group (un-treated control, n = 4), the BDL(+)/Rapa(+) group (treated 14 d after BDL, n = 8), the BDL(+)/Rapa(++) group (treated on the day after BDL, n = 8), and the BDL(-)/Rapa(-) group (un-treated, sham -operated control, n = 4).

Epigenetic silencing of BTB and CNC homology 2 and concerted promoter CpG methylation in gastric cancer.

BTB and CNC homology 2 (BACH2) is a lymphoid-specific transcription factor with a prominent role in B-cell development. Genetic polymorphisms within a single locus encoding BACH2 are associated with various autoimmune diseases and allergies. In this study, restriction landmark genomic scanning revealed methylation at a NotI site in a CpG island covering the BACH2 promoter in gastric cancer cell lines and primary gastric tumors.

Integrative genomics analysis reveals the multilevel dysregulation and oncogenic characteristics of TEAD4 in gastric cancer.

Tumorigenesis is a consequence of failures of multistep defense mechanisms against deleterious perturbations that occur at the genomic, epigenomic, transcriptomic and proteomic levels. To uncover previously unrecognized genes that undergo multilevel perturbations in gastric cancer (GC), we integrated epigenomic and transcriptomic approaches using two recently developed tools: MENT and GENT. This integrative analysis revealed that nine Hippo pathway-related genes, including components [FAT, JUB, LATS2, TEA domain family member 4 (TEAD4) and Yes-associated protein 1 (YAP1)] and targets (CRIM1, CYR61, CTGF and ITGB2), are concurrently hypomethylated at promoter CpG sites and overexpressed in GC tissues.

A known expressed sequence tag, BM742401, is a potent lincRNA inhibiting cancer metastasis.

Long intergenic non-coding RNAs (lincRNAs) have historically been ignored in cancer biology. However, thousands of lincRNAs have been identified in mammals using recently developed genomic tools, including microarray and high-throughput RNA sequencing (RNA-seq). Several of the lincRNAs identified have been well characterized for their functions in carcinogenesis.

Aberrant upregulation of ASCL2 by promoter demethylation promotes the growth and resistance to 5-fluorouracil of gastric cancer cells.

Achaete scute-like 2 (ASCL2), a basic helix-loop-helix transcription factor, plays an essential role in the maintenance of adult intestinal stem cells. However, the function of ASCL2 in gastric cancer (GC) is poorly understood. Therefore, we investigated the roles and regulatory transcription mechanisms of ASCL2 in GC.

Retrospective analysis of treatment outcomes after postoperative chemoradiotherapy in advanced gastric cancer.

Purpose: To evaluate retrospectively the survival outcome, patterns of failure, and complications in patients treated with postoperative chemoradiotherapy (CRT) in advanced gastric cancer.

Materials And Methods: Between January 2000 and December 2006, 80 patients with advanced gastric cancer who received postoperative concurrent CRT were included. Pathological staging was IB-II in 9%, IIIA in 38%, IIIB in 33%, and IV in 21%.

Quantitative analysis of cell-free DNA in the plasma of gastric cancer patients.

In the present study, an accurate and reproducible method for quantifying cell-free DNA (cfDNA) in human blood was established and tested for its ability to predict gastric cancer in patients. Using 'Alu81-qPCR' to amplify 81-bp Alu DNA sequences, we first estimated the amount of cfDNA in the serum or plasma of 130 patients with gastric cancer to identify which source of cfDNA is more suitable for the biomarker screening of these patients. The results of Alu81-qPCR revealed that the amount of cfDNA in the plasma was low compared with that in the serum, but was found at similar levels among the samples, indicating that the plasma may be a more suitable source of cfDNA for biomarker screening.

Pyruvate kinase M2 promotes the growth of gastric cancer cells via regulation of Bcl-xL expression at transcriptional level.

PKM2 is an isoenzyme of the glycolytic enzyme pyruvate kinase that promotes aerobic glycolysis. Here, we describe an important role for PKM2 in regulating the survival of gastric cancer (GC) cells. We showed that PKM2 was overexpressed in gastric tumor tissues compared to normal tissues and its expression level was associated with poor survival of gastric cancer patients.

Epigenetic alteration of CCDC67 and its tumor suppressor function in gastric cancer.

In this study, the promoter of the gene coiled-coil domain-containing 67 (CCDC67) was found to be frequently methylated in gastric cancer cell lines and in primary gastric tumors, as examined by restriction landmark genomic scanning. In addition, CCDC67 expression was down-regulated in 72.7% of gastric cancer cell lines tested.

The single incision laparoscopic intragastric wedge resection of gastric submucosal tumor.

Purpose: Laparoscopic wedge resection of gastric submucosal tumor may be difficult in case of the endophytic mass or the mass located unreachable area such as cardia, and intragastric approach can be useful. We would present the experiences of the intragastric wedge resection.

Materials And Methods: There were 7 patients diagnosed as gastric submucosal tumor and underwent the intragastric wedge resection at Surgery, Chungnam National University Hospital.

Prognostic significance of preoperative blood transfusion in stomach cancer.

Purpose: We did a retrospective study to understand the prognostic effects of preoperative blood transfusions in stomach cancer surgery.

Materials And Methods: Data for 1,360 patients who underwent gastrectomy for stomach cancer between 2001 and 2009 were retrospectively reviewed. We analyzed factors that affect preoperative transfusion and clinicopathologic features.

Identification of potential serum biomarkers for gastric cancer by a novel computational method, multiple normal tissues corrected differential analysis.

Background: Genes specifically expressed in one or a few tissues and upregulated in tumors are potentially good serum biomarkers.

Methods: By applying a recently developed computational method, called multiple normal tissues corrected differential analysis (MNTDA), we identified genes that are likely to be upregulated in the blood of gastric cancer patients as compared to normal controls.

Results: We identified four genes (MMP-1, MMP-3, MMP-12, and CXCL5) as potential serum biomarkers for gastric cancer.

Elevated fibroblast growth factor-inducible 14 expression promotes gastric cancer growth via nuclear factor-κB and is associated with poor patient outcome.

The fibroblast growth factor-inducible 14 (Fn14) gene encodes a type I transmembrane protein that belongs to the tumor necrosis factor receptor superfamily and regulates multiple cellular processes in diverse physiological and pathological conditions, including cancer. Here, we describe an important role for Fn14 in regulating the growth of gastric cancer cells. Previous gene expression data analysis demonstrated that Fn14 was up-regulated in various tumor tissues, including gastric cancer.

Epigenetic regulation of microRNA-10b and targeting of oncogenic MAPRE1 in gastric cancer.

MicroRNAs act as negative regulators of gene expression, and the altered expression of microRNAs by epigenetic mechanisms is strongly implicated in carcinogenesis. Here we report that the microRNA-10b gene (miR-10b) was silenced in gastric cancer cells by promoter methylation. In this study, using a methylation array and bisulfate pyrosequencing analysis, we found that miR-10b promoter CpGs were heavily methylated in gastric cancers.

Aberrant up-regulation of LAMB3 and LAMC2 by promoter demethylation in gastric cancer.

The LAMB3 and LAMC2 genes encode the laminin-5 β3 and γ2 chains, respectively, which are parts of laminin-5, one of the major components of the basement membrane zone. Here, we report the frequent up-regulation of LAMB3 and LAMC2 by promoter demethylation in gastric cancer. Gene expression data analysis showed that LAMB3 and LAMC2 were up-regulated in various tumor tissues.

Enigma negatively regulates p53 through MDM2 and promotes tumor cell survival in mice.

The human E3 ubiquitin ligase murine double minute 2 (MDM2) targets the tumor suppressor p53 for ubiquitination and degradation but also promotes its own ubiquitination and subsequent degradation. As the balance between MDM2 and p53 levels plays a crucial role in regulating cell proliferation and apoptosis, we sought to identify factors selectively inhibiting MDM2 self-ubiquitination. Here we have shown that the LIM domain protein Enigma directly interacts with MDM2 to form a ternary complex with p53 in vitro and in human hepatoma and colon carcinoma cell lines and mouse embryonic fibroblasts.

Frequent silencing of popeye domain-containing genes, BVES and POPDC3, is associated with promoter hypermethylation in gastric cancer.

The Popeye domain-containing (POPDC) genes BVES, POPDC2 and POPDC3 encode proteins that regulate cell-cell adhesion and cell migration during development. Herein, we report the frequent downregulation of BVES and POPDC3 by promoter hypermethylation in gastric cancer. POPDC expression in 11 gastric cancer cell lines and 96 paired gastric tumor and normal adjacent tissues was analyzed with quantitative reverse transcription-polymerase chain reaction.

Activation of AMP-activated protein kinase on human gastric cancer cells by apoptosis induced by corosolic acid isolated from Weigela subsessilis.

Corosolic acid is one of the triterpenoids present in the leaves of Weigela subsessilis. The antidiabetic activity of corosolic acid has been reported previously, but to date, the anticancer effects on gastric cancer have been poorly studied. In this study, corosolic acid showed growth inhibition on SNU-601 human gastric cancer cells, with an IC₅₀ value of 16.

SERPINE1 intron polymorphisms affecting gene expression are associated with diffuse-type gastric cancer susceptibility.

Background: A primary inhibitor of plasminogen activators, SERPINE1 (serpin peptidase inhibitor 1, clade E, member 1, also known as plasminogen activator inhibitor type 1), is an important regulator in tumorigenesis and is highly expressed in many cancers.

Methods: Five tag single nucleotide polymorphisms (SNPs) and 1 insertion polymorphism within SERPINE1 were genotyped in 1101 unrelated Korean individuals (a case group of 612 patients with gastric cancer and a control group of 489 healthy individuals). Associations with susceptibility to diffuse-type gastric cancer (DGC) and intestinal-type gastric cancer were assessed using multivariate logistic regression analyses adjusted for age and sex.

A regulatory polymorphism at position -309 in PTPRCAP is associated with susceptibility to diffuse-type gastric cancer and gene expression.

PTPRCAP (CD45-AP) is a positive regulator of protein tyrosine phosphatase PTPRC (CD45), which activates Src family kinases implicated in tumorigenesis. Single-nucleotide polymorphism (SNP) rs869736 located at position -309 of the PTPRCAP promoter was associated with susceptibility to diffuse-type gastric cancer in the current case-control study. The minor-allele homozygote was significantly associated with a 2.

[Comparision between proximal gastrectomy and total gastrectomy in early gastric cancer].

Background/aims: The purpose of this study was to evaluate clinical outcome of proximal and total gastrectomy regarding reflux esophagitis, nutritional state, and anemia in early gastric cancer.

Methods: 94 patients with early gastric cancer were included from January 2001 to January 2007 at Chungnam National University Hospital. Of whom 40 patients (31 men and 9 woman) had proximal gastrectomy (PG) and 54 patients (44 men and 10 woman) had total gastrectomy (TG).

Genetic variants A1826H and D2937Y in GAG-beta domain of versican influence susceptibility to intestinal-type gastric cancer.

Purpose: Versican regulates adhesion, migration, proliferation, and survival of cells, and plays an important role in cancer development. A case-control association study was performed to test genetic association of versican polymorphisms with susceptibility to gastric cancer.

Methods: In this study, 1,101 unrelated Korean subjects including 612 gastric cancer patients and 489 healthy controls were genotyped for all 21 exonic polymorphisms in the versican gene (VCAN) encoding amino acid changes in versican.

The expression of VEGF receptor genes is concurrently influenced by epigenetic gene silencing of the genes and VEGF activation.

Vascular endothelial growth factor (VEGF) activates the VEGF-VEGF receptor (VEGFR) signaling pathway in angiogenesis. Some cancer cell lines show decreased expression of the two VEGFRs, Flt-1 and KDR, even though VEGF is uniformly expressed in cancer cell lines. Promoter methylation is a well-known cause of epigenetic gene silencing in cancer cells.

The expression of VEGF receptor genes is concurrently influenced by epigenetic gene silencing of the genes and VEGF activation.

Vascular endothelial growth factor (VEGF) activates the VEGF-VEGF receptor (VEGFR) signaling pathway in angiogenesis. Some cancer cell lines show decreased expression of the two VEGFRs, Flt-1 and KDR, even though VEGF is uniformly expressed in cancer cell lines. Promoter methylation is a well-known cause of epigenetic gene silencing in cancer cells.

LRRC3B, encoding a leucine-rich repeat-containing protein, is a putative tumor suppressor gene in gastric cancer.

Leucine-rich repeat-containing 3B (LRRC3B) is an evolutionarily highly conserved leucine-rich repeat-containing protein, but its biological significance is unknown. Using restriction landmark genomic scanning and pyrosequencing, we found that the promoter region of LRRC3B was aberrantly methylated in gastric cancer. Gastric cancer cell lines displayed epigenetic silencing of LRRC3B, but treatment with the DNA methylation inhibitor 5-aza-2'-deoxycytidine and/or the histone deacetylase inhibitor trichostatin A increased LRRC3B expression in gastric cancer cell lines.