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The fragile histidine triad (FHIT) gene, encompassing the FRA3B fragile site at chromosome 3p14.2, is a candidate tumour suppressor gene involved in a variety of tumours, including gastric carcinomas. Recently, it has been reported that the FHIT gene may be a target of damage in some of mismatch-deficient tumours. To clarify further the role of the Fhit protein in gastric carcinogenesis, we investigated whether Fhit expression in early gastric neoplasia is associated with mismatch repair protein expression and cellular phenotype. Fhit, Mlh1 and phenotypic expression were evaluated immunohistochemically in 87 early gastric neoplasias, comprising 32 adenomas and 55 intramucosal carcinomas, resected by endoscopic mucosal resection therapy. Significant loss or reduction of Fhit expression was noted in four (12.5%) of the 32 adenomas and 21 (38.2%) of the 55 intramucosal carcinomas. The rate of abnormal Fhit expression was significantly higher in intramucosal carcinomas than in adenomas (P=0.021). Moreover, reduced Fhit expression was found to be significantly associated with loss of Mlh1 expression in early gastric neoplasia (P=0.0011). Furthermore, we also detected a significant association between reduced Fhit expression and gastric phenotype (P=0.0018). These results suggested that reduced Fhit expression occurs in the early stage of gastric carcinogenesis and could be correlated with a lack of Mlh1 expression and gastric phenotype.

The Fragile Histidine Triad gene, encompassing the FRA3B fragile site at chromosome 3p14.2, is a candidate tumour suppressor gene involved in multiple tumour types including colorectal carcinomas. Recently, it has been reported that the Fragile Histidine Triad gene may be a target of damage in a fraction of mismatch deficient tumours. To explore this hypothesis, we analysed both Fragile histidine triad and mismatch repair protein (Msh2 and Mlh1) expression using immumohistochemical methods in 52 advanced colorectal carcinomas (19 well-, 17 moderately-, and 16 poorly-differentiated). In addition, we examined whether the Fragile histidine triad and mismatch repair protein expression correlated with p53 expression and clinicopathological findings. Significant loss or reduction of Fragile histidine triad expression was noted in 18 of the 52 (34.6%) advanced colorectal carcinomas: 2 (10.5%) well-differentiated, 3 (17.6%) moderately-differentiated, 13 (81.3%) poorly-differentiated carcinomas, the frequency being significantly higher in the latter than that in the former two (P

Hepatocyte growth factor (HGF) has been reported to be a potent mitogen for hepatocytes in vivo and in vitro. Recent reports have shown that HGF has cytoprotective actions in acute liver injury models, but its mechanisms remain to be resolved. In the present study, we investigated whether HGF could work as an anti-hepatitis agent for acute liver injury caused by D-galactosamine (D-GalN) using transgenic (TG) mice expressing HGF in hepatocytes, compared with wild-type (WT) mice of their siblings. After administration of 3 g/kg body weight of D-GalN, elevated serum transaminase levels and severe liver damage that were observed in WT mice were significantly improved in TG mice. In TG mice, the percentage of proliferating cell nuclear antigen (PCNA)-positive hepatocytes was high at 0 hours after D-GalN treatment, and increased at 24 hours. The percentage of PCNA-positive cells in WT mice was very low at 0 hours and 24 hours after treatment, but increased at 48 hours. To clarify the mechanisms via which HGF acts, we measured hepatic HGF and prostaglandin E2 (PGE2) contents after D-GalN administration by an enzyme immunoassay. Total hepatic HGF contents, which were composed of murine (endogeneous) and human (derived from transgene) HGF, in TG mice were higher than those in WT mice at 0, 12, and 24 hours after administration of 3 g/kg body weight of D-GalN. Hepatic PGE2 contents in TG mice were also significantly higher than those in WT mice. Hepatic PGE2 contents had a positive correlation with total HGF contents at both 12 hours and 24 hours after the treatment. Moreover, an administration of 0.5 microg of anti-HGF antibody into the portal vein suppressed hepatic PGE2 contents of mice, compared with saline-injected mice in acute liver injury. Anti-PGE2 antibody administration caused more severe liver damage than saline solution. A survival rate of TG mice that were given 6 g/kg body weight of D-GalN-a lethal dose of D-GalN-was improved compared with WT mice. These results provided direct evidences that HGF worked as an anti-hepatitis agent against acute liver injury caused by D-GalN, and that this action might be exerted through accelerated hepatic PGE2 production.

Purpose. Non-steroidal anti-inflammatory drugs, including sulindac, have been shown to exhibit anti-colon cancer activity; however, the detailed mechanisms concerning continuous long-term administration are still unclear. Therefore, we examined the anti-colon carcinogenesis effects of sulindac after prolonged administration. Methods. Administration of AOM, a colon-specific carcinogen, induced colonic preneoplastic lesions, which can progress to carcinomas about 40–50 weeks after AOM administration. We studied the effects of sulindac on the incidence of preneoplastic lesions, proliferative activity of colonic cells (AgNORs), tumor suppressor adenomatous polyposis coli (APC) gene expression, and apoptosis using AOM-treated rat colon mucosa at 4 weeks and 40 weeks (early and late stage of colon carcinogenesis, respectively). Results. Sulindac suppressed the development of preneoplastic lesions induced by AOM at 4 weeks and 40 weeks by about 50% (P

BACKGROUND—Non-steroidal anti-inflammatory drugs (NSAIDs) have been reported to protect against the development of colon cancer. However, the mechanism(s) by which NSAIDs exert their effects is not clear. AIMS—The aim of this study was to examine the effects of NSAIDs on mRNA expression of tumour suppressor adenomatous polyposis coli (APC) gene in rat colon mucosa. METHODS—Starting at six weeks of age, three groups of rats (groups 1, 2, and 3) were treated with azoxymethane (AOM), a colon specific carcinogen, and another three groups (groups 4, 5, and 6) were not given AOM. Groups 2 and 3 were given 10 mg/kg of sulindac or etodolac, respectively, three times weekly during the experiment. Groups 4 and 5 were also given sulindac or etodolac, respectively, in the same manner as in groups 2 and 3. Group 6 (untreated control) was not given any agent (AOM or NSAIDs). At 10 weeks of age, preneoplastic lesions (aberrant crypt foci (ACF)) induced by AOM in the colon were counted, and the level of expression of APC mRNA in the colonic mucosa was estimated by the reverse transcription-competitive polymerase chain reaction method and northern blot analysis. RESULTS—Mean occurrence of ACF in rats in groups 2 and 3 was reduced to approximately 50% of that in group 1. The level of APC mRNA expression in group 1 (AOM alone) was lower than that in group 6 (untreated control) (p

The effect of dietary administration of cholic acid on tumorigenesis in the liver was investigated in male Fischer-344 rats after carcinogenic initiation by diethylnitrosamine (DEN); progression of liver tumors was examined in the rats fed 0.4% cholic acid-containing diet (CA group) and the rats fed standard diet (C group) at 15, 20 and 25 weeks after administration of DEN. The total bile acids and cholic acid in serum of CA group were 150 nmol/ml and 117 nmol/ml, being 31-fold and 51-fold higher than those in C group (p

Cell plasticity of bone marrow stem cells to hepatocytes is known, however, the details are still unclear. hepatocyte growth factor (HGF) promotes an increase in liver stem cells in severely injured liver, but intervention to bone marrow stem cell is unclear. We examined a role of HGF in bone marrow stem cell-mediated liver regeneration in order to obtain effective liver regeneration. First, we found that the phenotype of stem cells, which can differentiate into hepatocytes, is Lin−c-kit+Sca-1+CD34− in bone marrow or Lin−c-kit+Sca−1+CD34+ in peripheral blood mobilized by G-CSF. We transplanted single Lin−c-kit+Sca-1+CD34− bone marrow cell harvested from male EGFP mouse to female wild type mouse, and then, using this GFP-chimera-mouse, we found that bone marrow origin GFP+ and Y chromosome+ hepatic cells were present in liver after acute liver damage. Next, single Lin−c-kit+Sca-1+CD34+ peripheral blood cell, which was mobilized in peripheral blood by administration of G-CSF, was transplanted into the portal vein of the wild type mouse which was given hepatic damage. We found that the GFP-positive cells also expressed albumin. Second, we investigated whether the HGF can mobilize stem cells from bone marrow to peripheral blood. In peripheral blood of HGF transgenic mice, 1.1% developed CD34+ cells and 20±3 colony forming cells of 1X106 peripheral blood mononuclear cells were shown. Colony forming cells were found in the mouse into which an HGF-expressing adenovirus was administered. After injection of rHGF to mice, a significant time-dependent increase of percentage of CD34+ cells in the PB was noted at the first 3 hours and CD34+ cells were increased in dose-dependent manner of rHGF and reached plateau level at 100 m/kg. The mice having transplantation with PB cells from 100 mg HGF-treated mice for 4days showed engraftment 2 months after transplantation. Upon activation of rHGF in mouse MS-5 stromal cells, phosphorylation c-Met and SCF were up-regulated, while VCAM -1, MMP-9, SDF -1 or CXCR4 were not changed. SCF level in conditioned media was also increased after the HGF stimulation. Finally, we examined whether the bone marrow stem cells in PB mobilized by HGF transdifferentiate into hepatocytes. Using GFP-chimera-mice given acute liver injury after administration of retorolusine and CCl4, the levels of GFP+ cells in liver of GFP-chimera-mice 2 months after treatment by PBS and HGF were 2.2±1.4% and 12.7±3.6%, respectively (p

Objective and Design: The study examined plasma levels of hepatocyte growth factor (HGF) in acute colitis models on mice.¶Materials: Acute colitis was induced in male FVB mice (about 25 g) by intrarectal administration of 200 l of 0.5% acetic acid.¶Methods: Plasma was taken at 0, 12, 24, 36, 48 and 72 h after acetic acid treatment. Plasma HGF was measured by an enzyme immunoassay in duplicate.¶Results: Plasma levels of HGF at 0, 12, 24, 36, 48 and 72 h after acetic acid administration were 0.31 ± 0.11 ng/ml (n = 4), 0.45 ± 0.04 ng/ml (n = 4), 0.46 ± 0.13 ng/ml (n = 4), 0.71 ± 0.22 ng/ml (n = 4), 0.82 ± 0.15 ng/ml (n = 4) and 0.44 ± 0.04 ng/ml (n = 4), respectively. Significant increases in plasma HGF levels were observed at 36 and 48 h after the treatment (p

A 20-year-old man with hepatocellular carcinoma (HCC) died of intraperitoneal bleeding from ruptured HCC, which was diagnostic from hemorrhagic ascites. At autopsy, a small nodule covered with hematogenous deposits was noted in the pelvic cavity near the left iliac artery. Microscopic findings showed that this was a ruptured metastatic nodule from HCC. Rupture of a metastatic nodule from HCC, especially one located on the peritoneal surface, has rarely been reported in the literature.