Fas Regulates Macrophage Polarization and Fibrogenic Phenotype in a Model of Chronic Ethanol-Induced Hepatocellular Injury.

The role of Fas-mediated apoptosis and its effect on proinflammatory cytokine production in early alcoholic liver disease has not been addressed. Wild-type mice (C57Bl/6) or mice with a functional mutation in the Fas ligand (B6.gld) were given either high-fat control diet or ethanol diet by intragastric cannulation for 2 or 4 weeks. Liver injury, hepatic lipid accumulation, and proinflammatory cytokine production associated with chronic ethanol consumption were largely prevented in B6.gld mice compared with wild-type mice. Conversely, B6.gld mice given ethanol exhibited increases in collagen deposition, hepatic collagen gene expression, and profibrogenic cytokines (eg, transforming growth factor-ß and IL-13) and alterations in matrix remodeling proteins (eg, matrix metalloproteinases and tissue inhibitor of metalloproteinases) compared with wild-type mice. Hepatic F4/80(+) macrophage populations were increased significantly in B6.gld mice compared with wild-type mice; hepatic CD3(+) cell populations were not significantly different. Importantly, a shift toward the expression of M2/Th2 cytokines (eg, IL-4 and IL-13) after ethanol exposure was observed in B6.gld mice compared with classical M1 cytokine expression in wild-type mice under similar conditions. In isolated macrophages, stimulation of Fas receptor minimally enhances lipopolysaccharide-induced M1 cytokine production and significantly limits M2 cytokine production. These data support the hypothesis that Fas-mediated signaling is important for an early ethanol-induced proinflammatory response but limits the profibrogenic response, regulating collagen production in response to chronic ethanol.

Docetaxel, cisplatin and 5-fluorouracil adjuvant chemotherapy following three-field lymph node dissection for stage II/III N1, 2 esophageal cancer.

To determine the efficacy of postoperative adjuvant chemotherapy with docetaxel + cisplatin + 5-fluorouracil (DCF) in lymph node metastasis-positive esophageal cancer, we retrospectively analyzed 139 patients with stage II/III (non-T4) esophageal cancer with lymph node metastasis (1-6 nodes), who did not receive preoperative treatment and underwent three-field lymph node dissection in the Juntendo University Hospital between December, 2004 and December, 2009. The tumors were histologically diagnossed as squamous cell carcinoma. The patients were divided into two groups, a surgery alone group (S group, 88 patients) and a group that received postoperative DCF therapy (DCF group, 51 patients). The disease-free and overall survival were compared between the groups and a multivariate analysis of prognostic factors was performed. The same analysis was performed for cases classified as N1 and N2, according to the TNM classification. There were no significant differences between the S and DCF groups regarding clinicopathological factors other than intramural metastasis and main tumor location. The presence of intramural metastasis, blood vessel invasion and the number of lymph nodes were identified as prognostic factors. The 5-year disease-free and overall survival were 55.8 and 57.3%, respectively, in the S group and 52.8 and 63.0%, respectively, in the DCF group. These differences were not considered to be statistically significant (P=0.789 and 0.479 for disease-free and overall survival, respectively). Although there were no significant differences in disease-free and overall survival between the S and DCF groups in N1 cases, both disease-free and overall survival were found to be better in the DCF group (54.2 and 61.4%, respectively) compared to the S group (29.6 and 28.8%, respectively) in N2 cases (P=0.029 and 0.020 for disease-free and overall survival, respectively). Therefore, postoperative adjuvant chemotherapy with DCF was shown to improve disease-free and overall survival in moderate lymph node metastasis-positive cases (N2), suggesting that the DCF regimen may be effective as postoperative adjuvant chemotherapy for patients with lymph node metastasis from esophageal cancer.

Current status of primary malignant melanoma of the esophagus: clinical features, pathology, management and prognosis.

Primary malignant melanoma of the esophagus (PMME) is a rare disease with an extremely poor prognosis. Up to 2011, approximately 300 cases had been reported worldwide. The average age of onset is 60.5 years old, with a prevalence of males (2:1). A typical finding of PMME is a lobular or polyploid, well-circumscribed and pigmented tumor, partly covered with normal mucosa. PMME represents various colors depending on its melanin quantity and commonly coexists with intramural metastases, melanocytosis or melanoma in situ. The tumor is located from the middle to lower thoracic esophagus. The accuracy of diagnosis from biopsy is approximately 80%, because many cases are misdiagnosed as a poorly differentiated carcinoma because of the absence of melanin granules. A definite diagnosis was made by immunohistochemical examination with positive results of S100 protein, HMB45 and neuron-specific enolase. PMME has a highly metastatic potential, and the incidence of distant metastasis at the initial diagnosis is around 40-80%. A metastatic tumor from cutaneous malignant melanoma is another pigmented esophageal tumor to be considered when making the differential diagnosis for PMME. Junctional activity with melanotic cells in the adjacent epithelium and the presence of in situ melanoma and/or a satellite tumor without a previous history of cutaneous melanoma are definitive. Most of the reported patients were treated with radical esophagectomy, which is believed to be an effective approach for localized PMME. Five-year survival rates have been achieved in 37% recently, while adjuvant therapy has not been proven to increase overall survival but plays a palliative role.

[Trans-thoracic esophagectomy with 3-field lymph nodes dissection].

Although open-chest surgery is the mainstay treatment for esophageal cancer, the understanding of the context of the surgery differs in Japan and the rest of the world. Three-field lymph node dissection has been unique to Japan, although some reports on its benefits are emerging elsewhere. In addition to three-field lymph node dissection, various efforts are made during surgical procedures to reduce complications at high-volume Japanese healthcare institutions.

Study of abnormal chromosome regions in esophageal squamous cell carcinoma by comparative genomic hybridization: relationship of lymph node metastasis and distant metastasis to selected abnormal regions.

Squamous cell carcinoma of the esophagus (ESCC) has a poor prognosis among digestive tract cancers. Lymph node metastasis and distant metastasis are the major factors determining its prognosis. We used comparative genomic hybridization (CGH) to evaluate primary tumor lymph nodes and metastatic areas from ESCC patients in order to determine the relationship between abnormal chromosome regions and outcome. Tumor tissues and lymph nodes were collected from 51 patients with ESCC, and abnormal chromosome regions were detected by CGH. We searched for regions that were significantly more common in patients with lymph nodes metastases (n>/= 6) or distant metastases, and correlated those chromosomal changes with survival. Regions showing amplification in more than 65% of esophageal squamous cell cancers were as follows: 17q12 (90.2%), 17q21 (86.3%), 3q29 (82.4%), 3q28 (78.4%), 8q24.2 (76.5%), 22q12 (76.5%), 3q27 (74.5%), 8q24.3 (74.5%), 1q22 (70.6%), 5p15.3 (70.6%), 22q13 (70.6%), 3q26.3, 8q23, 8q24.1, 9q34, 11q13, 17p12, 17q25, 20q12, 20q13.1 (68.6%), 1q32, 1q42, and 20q13.2 (66.7%). Regions showing deletion in more than 50% of the tumors were as follows: Yp11.3 (62.7%), 3p26 (56.9%), Yq12 (54.9%), 13q21 (52.9%), 4q32 (51.0%), and 13q22 (51.0%). When Fisher's test was used to assess associations of these regions with metastases to lymph nodes, amplification at 2q12-14 (P= 0.012), 3q24-26 (P= 0.005), and 7q21-31 (P= 0.026) were significant. Survival was worse for patients with amplification at all 3 regions. In patients with distant organ metastases, amplification at 7p13-21 was significant (P= 0.008), and survival was worse. Chromosomal amplifications in ESCC at 2q12-14, 3q24-26, and 7q21-31 were associated with lymph node metastasis, while amplification at 7p13-21 was related to distant metastasis. Amplification at these regions correlated with worse survival. Genes involved in the phenotype of ESCC may exist in these regions. Identification of these genes is a theme for future investigation.

Impaired liver regeneration and increased oval cell numbers following T cell-mediated hepatitis.

UNLABELLED: The regeneration of liver tissue following transplantation is often complicated by inflammation and tissue damage induced by a number of factors, including ischemia and reperfusion injury and immune reactions to the donor tissue. The purpose of the current study is to characterize the effects of T cell-mediated hepatitis induced by concanavalin A (ConA) on the regenerative response in vivo. Liver regeneration following a partial (70%) hepatectomy (pHx) was associated with elevations in serum enzymes and the induction of key cell cycle proteins (cyclin D, cyclin E, and Stat3) and hepatocyte proliferation. The induction of T cell-mediated hepatitis 4 days before pHx increased serum enzymes 48 hours after pHx, reduced early cyclin D expression and Stat3 activation, and suppressed hepatocyte proliferation. This inhibition of proliferation was also associated with increased expression of p21, the activation of Smad2, the induction of transforming growth factor beta and interferon gamma expression, and reduced hepatic interleukin 6 production. Moreover, the ConA pretreatment increased the numbers of separate oval cell-like CD117(+) cells and hematopoietic-like Sca-1(+) cell populations 48 hours following pHx. The depletion of natural killer (NK) cells, an important component of the innate immune response, did not affect liver injury or ConA-induced impairment of hepatocyte proliferation but did increase the numbers of both CD117-positive and Sca-1-positive cell populations. Finally, splenocytes isolated from ConA-pretreated mice exerted cytotoxicity toward autologous bone marrow cells in an NK cell-dependent manner. CONCLUSION: T cell-mediated hepatitis alters early cytokine responses, reduces hepatocellular regeneration, and induces NK cell-sensitive oval cell and hematopoietic-like cell expansion following pHx.

LPS signaling enhances hepatic fibrogenesis caused by experimental cholestasis in mice.

Although it is clear that bile acid accumulation is the major initiator of fibrosis caused by cholestatic liver disease, endotoxemia is a common side effect. However, the depletion of hepatic macrophages with gadolinium chloride blunts hepatic fibrosis. Because endotoxin is a key activator of hepatic macrophages, this study was designed to test the hypothesis that LPS signaling through CD14 contributes to hepatic fibrosis caused by experimental cholestasis. Wild-type mice and CD14 knockout mice (CD14(-/-)) underwent sham operation or bile duct ligation and were killed 3 wk later. Measures of liver injury, such as focal necrosis, biliary cell proliferation, and inflammatory cell influx, were not significantly different among the strains 3 wk after bile duct ligation. Markers of liver fibrosis such as Sirius red staining, liver hydroxyproline, and alpha-smooth muscle actin expression were blunted in CD14(-/-) mice compared with wild-type mice after bile duct ligation. Despite no difference in lymphocyte infiltration, the macrophage/monocyte activation marker OX42 (CD11b) and the oxidative stress/lipid peroxidation marker 4-hydroxynonenal were significantly upregulated in wild-type mice after bile duct ligation but not in CD14(-/-) mice. Increased profibrogenic cytokine mRNA expression in the liver after bile duct ligation was significantly blunted in CD14(-/-) mice compared with the wild type. The hypothesis that LPS was involved in experimental cholestatic liver fibrosis was tested using mice deficient in LPS-binding protein (LBP(-/-)). LBP(-/-) mice had less liver injury and fibrosis (Siruis red staining and hydroxyproline content) compared with wild-type mice after bile duct ligation. In conclusion, these data demonstrate that endotoxin in a CD14-dependent manner exacerbates hepatic fibrogenesis and macrophage activation to produce oxidants and cytokines after bile duct ligation.

Cytochrome P450 CYP2E1, but not nicotinamide adenine dinucleotide phosphate oxidase, is required for ethanol-induced oxidative DNA damage in rodent liver.

The occurrence of malignant tumors of the upper gastrointestinal tract and liver is, based largely on epidemiological evidence, causally related to the consumption of ethanol. It is widely recognized that oxidants play a key role in alcohol-induced liver injury; however, it is unclear how oxidants may be involved in DNA damage. We asked whether nicotinamide adenine dinucleotide phosphate oxidase, cytochrome P450 CYP2E1, or both are responsible for the production of DNA damage. The rodent Tsukamoto-French model of intragastric ethanol infusion was used. Wistar rats, Cyp2e1-, p47(phox)-null, and hCyp2e1 transgenic mice were used. The abundance of oxidative DNA adducts, mutagenic apurinic/apyrimidinic sites, and expression of base excision DNA repair genes was determined. In rats and wild-type mice, ethanol treatment for 4 weeks led to an increase in oxidative DNA damage and induction of expression of the base excision DNA repair genes that are known to remove oxidative DNA lesions. No increase in either of the endpoints was observed in ethanol-treated Cyp2e1-null mice, whereas the magnitude of response in p47(phox)-null mice and transgenic hCyp2e1 was identical to that in wild types. The increase in expression of DNA repair genes was completely abolished by treatment with the P450 inhibitor 1-aminobenzotriazole. In conclusion, the data support the hypothesis that oxidative stress to DNA is induced in liver by ethanol. Furthermore, although it was shown that nicotinamide adenine dinucleotide phosphate oxidase-derived oxidants are critical for the development of ethanol-induced liver injury, CYP2E1 is required for the induction of oxidative stress to DNA, and thus may play a key role in ethanol-associated hepatocarcinogenesis.

Contribution of angiotensin II to alcohol-induced pancreatic fibrosis in rats.

The mechanisms by which alcohol causes pancreatic fibrosis remain unknown. Recent studies have demonstrated that angiotensin II contributes to the development of fibrosis in liver, kidney, and heart injury. Here, the effects of angiotensin-converting enzyme inhibitor (captopril) and angiotensin II receptor antagonist (losartan) on alcohol-induced pancreatic fibrosis were examined in an intragastric ethanol-feeding model. Male rats were fed a high-fat liquid diet with either ethanol (16-20 g/kg/day) or isocaloric maltose-dextrin (control) for 4 weeks. Subgroups daily received captopril (60 mg/kg/day), losartan (3 mg/kg/day), or no additional agent included in liquid diets. Mean urine alcohol concentrations in all groups fed ethanol were more than 270 mg/dl and not significantly different. Dietary alcohol caused diffuse gland atrophy and interlobular and intralobular fibrosis with mild structural distortion in the pancreas, an effect that was blunted by captopril or losartan treatment. Alcohol also increased the number of alpha-smooth muscle actin-positive cells and transforming growth factor-beta mRNA expression in the pancreas. These increases were blunted significantly by captopril or losartan treatment. These data suggest that angiotensin II contributes to the development of chronic alcohol-induced pancreatic fibrosis through its stimulation of transforming growth factor-beta expression.

TNF alpha-induced Ras activation due to ethanol promotes hepatocyte proliferation independently of liver injury in the mouse.

Tumor necrosis factor alpha (TNFalpha) has been shown to be both proapoptotic and mitogenic for hepatocytes and necessary for alcohol-induced liver injury. Ras, a known proto-oncogene, is very important in the regulation of cellular responses to TNFalpha. Therefore, the purpose of this study was to investigate the role of Ras in alcohol-induced pathogenesis. Male C57Bl/6 mice were fed ethanol or high-fat control diet via intragastric cannulation for 4 weeks. Ras activity was increased significantly after 4 weeks of ethanol and correlated with an increase in pathologic features. However, in mice deficient in the receptor-type 1 for TNFalpha (TNFR1(-/-)), ethanol-induced liver injury and the increase in Ras activity were significantly blunted compared with wild-type mice. Furthermore, it was demonstrated that H-, K-, and R-Ras isoforms were increased after ethanol exposure in wild-type mice. In TNFR1(-/-) mice, R-Ras activity remained elevated by ethanol, whereas H-Ras and K-Ras activity was blunted significantly under these conditions. Interestingly, hepatocellular proliferation, which was elevated approximately fivefold after 4 weeks of chronic ethanol in wild-type mice, was also blunted in TNFR1(-/-) mice given ethanol. Inhibition of Ras with adenovirus containing a dominant-negative Ras had no effect on ethanol-induced liver injury, but significantly blunted ethanol-induced hepatocyte proliferation by more than 50%. Overexpression of mitochondrial superoxide dismutase using recombinant adenovirus blunted lipid peroxidation and attenuated hepatic injury resulting from ethanol, but had no effect on Ras activation and hepatocyte proliferation caused by ethanol. In conclusion, these data support the hypotheses that hepatocellular oxidative stress leads to cell death and that TNFalpha-induced Ras activation is important in hepatic proliferation in response to ethanol-induced liver injury.

The CYP inhibitor 1-aminobenzotriazole does not prevent oxidative stress associated with alcohol-induced liver injury in rats and mice.

Cytochrome P450 (CYP) 2E1 is induced by ethanol and is postulated to be a source of reactive oxygen species during alcoholic liver disease. However, there was no difference in liver pathology and radical formation between wild-type and CYP2E1 knockout mice fed ethanol. Other CYP isoforms may contribute these effects if CYP2E1 is inhibited or absent. The purpose of this study was, therefore, to determine if blocking most of the P450 isoforms with 1-aminobenzotriazole (ABT; 100 mg/kg i.g.), has any effect on liver damage and oxidative stress due to alcohol in rats and mice. Male C57BL/6 mice and Wistar rats were fed either high-fat control or ethanol-containing enteral diet for 4 weeks. ABT had a significant inhibitory effect on many P450 isoforms independent of concomitant alcohol administration. However, ABT did not protect against liver damage due to alcohol in either species. Indices of oxidative stress and inflammation were also similar in livers from vehicle-treated and ABT-treated animals fed ethanol. In summary, suppression of P450 activity with ABT had no apparent effect on oxidative stress caused by alcohol in both rats and mice. These data support the hypothesis that oxidative stress and liver damage can occur independently of CYP activities in both rats and mice during early alcohol-induced liver injury.

Inducible nitric oxide synthase is required in alcohol-induced liver injury: studies with knockout mice.

BACKGROUND & AIMS: Oxidative stress contributes to early alcohol-induced liver injury, and superoxide (O(2)*-) production from NADPH oxidase plays a key role. However, the production of the free radical nitric oxide (NO*) by inducible nitric oxide synthase (iNOS) could also be involved. METHODS: To test this hypothesis, iNOS knockout (B6.129P2-Nos2 (tm1 Lau)) and wild-type mice were fed high-fat control or ethanol-containing diets for 4 weeks. RESULTS: Mean body weight gains were not significantly different between treatment groups, and average urine ethanol concentrations were similar in wild-type and iNOS knockout mice. After 4 weeks, serum alanine aminotransferase (ALT) levels were increased significantly about 4-fold over control values (29 +/- IU/L) by enteral ethanol (113 +/- 20) in wild-type mice; this effect of ethanol was significantly blunted in iNOS knockout mice (50 +/- 9). Similar protective effects against liver damage were observed if wild-type mice were treated with the iNOS inhibitor N -(3-aminomethyl)benzyl-acetamindine (1400W). Enteral ethanol also caused severe fatty accumulation, mild inflammation, and necrosis in the liver in wild-type mice but had no effect in iNOS knockout mice. The accumulation of 4-hydroxynonenal (lipid peroxidation) and 3-nitrotyrosine (reactive nitrogen species formation) protein adducts caused by alcohol was completely blocked in iNOS knockout mice. CONCLUSIONS: These data strongly support the hypothesis that iNOS is required for the pathogenesis of early alcohol-induced hepatitis by production of nitric oxide-derived pro-oxidants (e.g., peroxynitrite).

Role of lipopolysaccharide-binding protein in early alcohol-induced liver injury in mice.

Cellular responses to endotoxins are enhanced markedly by LPS-binding protein (LBP). Furthermore, it has been demonstrated that endotoxins and proinflammatory cytokines such as TNF-alpha participate in early alcohol-induced liver injury. Therefore, in this study, a long-term intragastric ethanol feeding model was used to test the hypothesis that LBP is involved in alcoholic hepatitis by comparing LBP knockout and wild-type mice. Two-month-old female mice were fed a high-fat liquid diet with either ethanol or isocaloric maltose-dextrin as control continuously for 4 wk. There was no difference in mean urine alcohol concentrations between the groups fed ethanol. Dietary alcohol significantly increased liver to body weight ratios and serum alanine aminotransferase levels in wild-type mice (189 +/- 31 U/L) over high-fat controls (24 +/- 7 U/L), effects which were blunted significantly in LBP knockout mice (60 +/- 17 U/L). Although no significant pathological changes were observed in high-fat controls, 4 wk of dietary ethanol caused steatosis, mild inflammation, and focal necrosis in wild-type animals as expected (pathology score, 5.9 +/- 0.5). These pathological changes were reduced significantly in LBP knockout mice fed ethanol (score, 2.6 +/- 0.5). Endotoxin levels in the portal vein were increased significantly after 4 wk in both groups fed ethanol. Moreover, ethanol increased TNF-alpha mRNA expression in wild-type, but not in LBP knockout mice. These data are consistent with the hypothesis that LBP plays an important role in early alcohol-induced liver injury by enhancing LPS-induced signal transduction, most likely in Kupffer cells.