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1.
Oncogene ; 36(36): 5134-5144, 2017 09 07.
Article in English | MEDLINE | ID: mdl-28481875

ABSTRACT

Toll-like receptors (TLRs) are key regulators of innate immune responses, and their dysregulation is observed in numerous inflammation-associated malignancies, including gastric cancer (GC). However, the identity of specific TLRs and their molecular targets which promote the pathogenesis of human GC is ill-defined. Here, we sought to determine the clinical utility of TLR2 in human GC. TLR2 mRNA and protein expression levels were elevated in >50% of GC patient tumors across multiple ethnicities. TLR2 was also widely expressed among human GC cell lines, and DNA microarray-based expression profiling demonstrated that the TLR2-induced growth responsiveness of human GC cells corresponded with the up-regulation of six anti-apoptotic (BCL2A1, BCL2, BIRC3, CFLAR, IER3, TNFAIP3) and down-regulation of two tumor suppressor (PDCD4, TP53INP1) genes. The TLR2-mediated regulation of these anti-apoptotic and tumor suppressor genes was also supported by their increased and reduced expression, respectively, in two independent genetic GC mouse models (gp130F/F and Gan) characterized by high tumor TLR2 expression. Notably, enrichment of this TLR2-regulated gene signature also positively correlated with augmented TLR2 expression in human GC tumors, and served as an indicator of poor patient survival. Furthermore, treatment of gp130F/F and cell line-derived xenograft (MKN1) GC mouse models with a humanized anti-TLR2 antibody suppressed gastric tumor growth, which was coincident with alterations to the TLR2-driven gene signature. Collectively, our study demonstrates that in the majority of GC patients, elevated TLR2 expression is associated with a growth-potentiating gene signature which predicts poor patient outcomes, thus supporting TLR2 as a promising therapeutic target in GC.


Subject(s)
Biomarkers, Tumor/metabolism , Cell Proliferation , Gene Expression Profiling , Stomach Neoplasms/pathology , Toll-Like Receptor 2/metabolism , Animals , Apoptosis , Biomarkers, Tumor/genetics , Female , Humans , Mice , Mice, Inbred NOD , Neoplasm Invasiveness , Neoplasm Staging , Prognosis , Stomach Neoplasms/genetics , Stomach Neoplasms/metabolism , Survival Rate , Toll-Like Receptor 2/genetics , Tumor Cells, Cultured , Xenograft Model Antitumor Assays
2.
Oncogene ; 33(19): 2540-6, 2014 May 08.
Article in English | MEDLINE | ID: mdl-23728346

ABSTRACT

Signalling by the toll-like receptor (TLR) family of pathogen recognition receptors has emerged as a key molecular component in the pathogenesis of an increasing number of inflammatory-related cancers, among which gastric cancer rates as the second most lethal cancer world-wide. The myeloid differentiation factor 88 (MyD88) adapter molecule has a critical role in mediating innate immune signalling by members of the TLR and interleukin (IL)-1 families, and has been associated with either pro- or antitumourigenic responses in various cancer models. However, little is known about the in vivo role of MyD88 adapter-like (Mal)/TIR-domain containing adapter protein (TIRAP), which is restricted to facilitating TLR4 and TLR2 signalling. To interrogate the role of these innate immune signalling components in gastric tumourigenesis, here we have employed the spontaneous gastric cancer gp130(F/F) mouse model, in which TLR2 promotes the growth of gastric tumours. Genetic ablation of Myd88 in gp130(F/F) mice suppressed tumourigenesis and was associated with increased apoptosis and reduced proliferation in the gastric tumour epithelium, comparable to that observed previously upon deletion of Tlr2 in gp130(F/F) mice. By contrast, the tumour burden in gp130(F/F):Mal(-/-) mice was equivalent to their gp130(F/F) littermates. At the molecular level, suppressed tumourigenesis in gp130(F/F):Myd88(-/-) mice correlated with reduced expression and activation of TLR2-regulated protumourigenic genes and signalling pathways, respectively. Consistent with the previously defined non-essential role for TLR2 in gastric tumour inflammation, the extent of inflammatory cell infiltrates in gastric tumours from gp130(F/F):Mal(-/-) and gp130(F/F):Myd88(-/-) mice remained unaltered compared with gp130(F/F) mice. Collectively, our data reveal a differential, but inflammation-independent, requirement for Mal and MyD88 during TLR2-promoted gastric tumourigenesis.


Subject(s)
Cell Transformation, Neoplastic/metabolism , Membrane Glycoproteins/metabolism , Myeloid Differentiation Factor 88/metabolism , Receptors, Interleukin-1/metabolism , Stomach Neoplasms/metabolism , Toll-Like Receptor 2/metabolism , Animals , Cell Transformation, Neoplastic/immunology , Disease Models, Animal , Immunoblotting , Immunohistochemistry , In Situ Nick-End Labeling , Membrane Glycoproteins/immunology , Mice , Mice, Knockout , Myeloid Differentiation Factor 88/immunology , Receptors, Interleukin-1/immunology , Reverse Transcriptase Polymerase Chain Reaction , Signal Transduction/physiology , Stomach Neoplasms/immunology , Stomach Neoplasms/pathology , Toll-Like Receptor 2/immunology
4.
J Clin Pathol ; 59(10): 1073-8, 2006 Oct.
Article in English | MEDLINE | ID: mdl-16679351

ABSTRACT

AIM: To compare cell phenotypes displayed by cholangiocarcinomas and adjacent bile duct lesions in patients from an area endemic in liver-fluke infestation and those with sporadic cholangiocarcinoma. METHODS: 65 fluke-associated and 47 sporadic cholangiocarcinomas and 6 normal livers were studied. Serial paraffin-wax sections were stained immunohistochemically with monoclonal antibodies characterising a Brunner or pyloric gland metaplasia cell phenotype (antigens D10 and 1F6), intestinal goblet cells (antigen 17NM), gastric foveolar apomucin (MUC5AC), a gastrointestinal epithelium cytokeratin (CK20) and the p53 protein. RESULTS: 60% of the 112 cholangiocarcinomas expressed antigen D10, 68% MUC5AC, 33% antigen 17NM and 20% CK20; 37% showed overexpression of p53. When present together in a cholangiocarcinoma, cancer cells expressing D10 were distinct from those displaying 17NM or MUC5AC. Many more fluke-associated cholangiocarcinomas than sporadic cholangiocarcinomas displayed 17NM and p53 expression. Most cases of hyperplastic and dysplastic biliary epithelium expressed D10 strongly. Pyloric gland metaplasia and peribiliary glands displayed D10 and 1F6, with peribiliary gland hyperplasia more evident in the livers with fluke-associated cholangiocarcinoma; goblet cells in intestinal metaplasia stained for 17NM. No notable association of expression between any two antigens (including p53) was found in the cancers. CONCLUSIONS: Most cases of dysplastic biliary epithelium and cholangiocarcinoma display a Brunner or pyloric gland cell phenotype and a gastric foveolar cell phenotype. The expression of D10 in hyperplastic and dysplastic epithelium and in cholangiocarcinoma is consistent with a dysplasia-carcinoma sequence. Many more fluke-associated cholangiocarcinomas than sporadic cholangiocarcinoma display an intestinal goblet cell phenotype and overexpress p53, indicating differences in the aetiopathology of the cancers in the two groups of patients.


Subject(s)
Antigens, Neoplasm/metabolism , Bile Duct Neoplasms/parasitology , Bile Ducts, Intrahepatic/metabolism , Cholangiocarcinoma/parasitology , Fascioliasis/complications , Adult , Aged , Aged, 80 and over , Bile Duct Neoplasms/metabolism , Bile Duct Neoplasms/pathology , Bile Ducts, Intrahepatic/pathology , Cholangiocarcinoma/metabolism , Cholangiocarcinoma/pathology , Disease Progression , Fascioliasis/metabolism , Female , Humans , Hyperplasia/metabolism , Hyperplasia/parasitology , Male , Metaplasia/metabolism , Metaplasia/parasitology , Middle Aged , Phenotype , Precancerous Conditions/metabolism , Precancerous Conditions/parasitology , Precancerous Conditions/pathology , Tumor Suppressor Protein p53/metabolism
5.
Dig Dis Sci ; 49(7-8): 1302-10, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15387361

ABSTRACT

We used conscious restrained rats, in which balloon distension of the colorectum was used as a repeated visceral stimulus over a 21-day period, either alone or in conjunction with a luminal irritant, dextran sodium sulfate (DSS), in order to elicit sensitization as evidenced by amplified blood pressure responses. Female Sprague Dawley rats received 5% DSS in the drinking water for 3 days. A water-filled balloon was used to distend the colorectum. Set volumes (1, 1.5, and 2 mL) were applied for 3 min, at 10-min intervals, weekly for 3 weeks, with colorectal and tail-cuff blood pressures measured. Tissue for mast cell localization and histology were taken from proximal and distal colon at sacrifice. Mean colorectal balloon pressures and blood pressures in the DSS-treated rats compared to controls were 12% (P < 0.01) and 64% (P < 0.03) higher, respectively. At sacrifice the DSS-treated rats had twice the number of mast cell numbers in the mucosa of the proximal colon compared to controls, suggesting that the sensitization effect may be linked to inflammatory mediators (P < 0.05).


Subject(s)
Colon/physiology , Eosinophils/cytology , Mast Cells/cytology , Rectum/physiology , Animals , Blood Pressure , Cell Count , Dextran Sulfate/pharmacology , Female , Immunohistochemistry , Inflammation/pathology , Intestinal Mucosa/cytology , Pressure , Rats , Rats, Sprague-Dawley , Restraint, Physical
6.
Aliment Pharmacol Ther ; 17(9): 1197-204, 2003 May 01.
Article in English | MEDLINE | ID: mdl-12752357

ABSTRACT

BACKGROUND: The optimal treatment for hepatitis C patients unresponsive to interferon is unclear. High-dose induction interferon may enhance early viral clearance, whilst ribavirin reduces relapse; in combination, they may improve sustained virological response rates. AIM: To compare the efficacy and safety of re-treatment with interferon induction, with or without ribavirin, in interferon non-responders. METHODS: We randomized 218 biochemical interferon non-responders to 10 MU interferon alpha 2b daily for 4 weeks, followed by 5 MU thrice weekly for 48 weeks plus ribavirin (II + R), or to the same interferon regimen plus placebo (II + P). All patients were viraemic at entry. RESULTS: The sustained virological response in the II + R group was 39%[95% confidence interval (CI), 30-48%], compared with 16% (95% CI, 9-23%) in the II + P group (P < 0.002). The study drug was discontinued for intolerable symptoms during induction in 9% of the II + R group and in 5% of the II + P group. By logistic regression, a sustained virological response was more likely following II + R treatment (odds ratio, 4.4; 95% CI, 2.1-9.7) and less likely in patients with genotype 1 or 4 (odds ratio, 0.16; 95% CI, 0.07-0.36). CONCLUSION: High-dose induction interferon plus ribavirin is well tolerated and effective for patients unresponsive to interferon alone.


Subject(s)
Antiviral Agents/administration & dosage , Hepatitis C, Chronic/drug therapy , Interferon-alpha/administration & dosage , Ribavirin/administration & dosage , Adolescent , Adult , Dose-Response Relationship, Drug , Drug Therapy, Combination , Female , Humans , Interferon alpha-2 , Interferon-alpha/adverse effects , Male , Middle Aged , Recombinant Proteins , Ribavirin/adverse effects , Treatment Outcome
7.
Bone Marrow Transplant ; 29(11): 931-3, 2002 Jun.
Article in English | MEDLINE | ID: mdl-12080360

ABSTRACT

Bone marrow transplantation is potentially curative therapy for the hematologic complications associated with Shwachman-Diamond syndrome (SDS). This syndrome is, however, also associated with significant pancreatic and hepatic dysfunction, which may complicate BMT. We report a case of liver failure due to non-alcoholic steatohepatitis (NASH) following BMT for SDS. This case illustrates the need for assessing liver dysfunction pre-BMT in these patients, in addition to highlighting the potential risk posed by pre-existing steatosis for the development of rapidly progressive hepatic failure following transplantation.


Subject(s)
Bone Marrow Transplantation/adverse effects , Exocrine Pancreatic Insufficiency/therapy , Hepatitis/etiology , Liver Failure/etiology , Adult , Contraindications , Exocrine Pancreatic Insufficiency/complications , Fatal Outcome , Fatty Liver/complications , Fatty Liver/etiology , Fatty Liver/pathology , Female , Hepatitis/complications , Hepatitis/pathology , Humans , Liver Failure/pathology , Myelodysplastic Syndromes/complications , Myelodysplastic Syndromes/therapy , Transplantation, Homologous/adverse effects
8.
Dis Colon Rectum ; 44(7): 947-54, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11496074

ABSTRACT

PURPOSE: The aim of this study was to determine the incidence of local pelvic recurrence of carcinoma of the rectum and rectosigmoid (tumors where the lower edge is 18 cm or less from the anal verge) in a consecutive series of patients operated on by a single surgeon. All patients underwent curative anterior resection and a formal anatomic dissection of the rectum where mobilization was achieved through a principally careful blunt manual technique along fascial planes, preserving an oncologic package. METHOD: During the period April 1986 to December 1997, 157 consecutive anterior resections for carcinoma of the rectum and rectosigmoid were performed by one surgeon (ALP). One hundred thirty-eight (87.9 percent) were curative, and 19 (12.1 percent) were palliative. The mean follow-up period was 46 +/- 31.6 (range, 2-140) months. Data were retrospectively collated and computer coded by an independent contracted medical research team. Follow-up data were available on all patients. RESULTS: Four (3.1 percent) of the 131 patients undergoing curative anterior resection had local recurrence. Local recurrences occurred between 16 and 38 months from the time of resection, and the cumulative risk of developing local recurrence at five years was 5.2 percent. All tumors in which pelvic recurrence occurred were high grade, and the probability of developing local recurrence at five years for this group was 13.9 percent, which is significantly higher compared with patients who had average or low-grade tumors (P = 0.01). The probability of developing local recurrence at five years for Stage I tumors was 0, Stage II was 5.9 percent, and Stage III was 8.9 percent. In addition, there was a significantly higher incidence of local recurrence in the group of patients undergoing ultralow anterior resection (between 3 and 6 cm from the anal verge) as compared with patients undergoing low or high anterior resection (P = 0.03). Local recurrence developed in 3 of 28 (10.7 percent) patients having ultralow anterior resection, 1 of 57 (1.8 percent) patients having low anterior resection (between 6 and 10 cm from the anal verge), and no patients having high anterior resection (above 10 cm from the anal verge). The clinical anastomotic leak rate for curative anterior resection was 7 of 131 patients (5.3 percent). Thirty-seven of the 131 (28.2 percent) required a proximal defunctioning stoma; 35 (41.2 percent) of these were established for low or ultralow anterior resections and 2 for high anterior resection. The overall five-year cancer-specific survival rate of the entire group of 131 patients was 81.8 percent, and the overall probability of being disease free at five years including both local and distal recurrence was 72.9 percent. Three local recurrences occurred in the 101 patients (77 percent) who did not receive any form of adjuvant therapy. One local recurrence occurred in the 18 patients (13.7 percent) who had adjuvant chemoradiation. No recurrence occurred in the 12 patients (9.2 percent) who had adjuvant chemotherapy alone. CONCLUSION: Curative anterior resection for carcinoma of the rectum and rectosigmoid with principally blunt dissection of the rectum in this study is associated with a 3.1 percent incidence and a 5.2 percent probability at five years of developing local recurrence. Evidence from this study indicates that, as with sharp pelvic dissection, a low incidence and probability of local recurrence can be achieved by a principally blunt mobilization technique through careful attention to preservation of fascial planes in the pelvis and removal of an oncologic package with selective rather than routine adjuvant or neoadjuvant chemoradiation.


Subject(s)
Carcinoma/surgery , Digestive System Surgical Procedures/methods , Neoplasm Recurrence, Local , Rectal Neoplasms/surgery , Sigmoid Neoplasms/surgery , Aged , Anastomosis, Surgical , Carcinoma/pathology , Female , Humans , Incidence , Male , Middle Aged , Neoplasm Staging , Prognosis , Rectal Neoplasms/pathology , Retrospective Studies , Risk Factors , Sigmoid Neoplasms/pathology , Time Factors , Treatment Outcome
9.
Gastroenterology ; 121(1): 91-100, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11438497

ABSTRACT

BACKGROUND AND AIMS: Nonalcoholic fatty liver disease (NAFLD) is common in severely obese subjects and can progress to cirrhosis and liver failure. Predicting advanced or progressive disease may help in selecting patients for liver biopsy and assist the development of therapeutic options. METHODS: Liver biopsies were taken at laparoscopic obesity surgery in 105 consecutive patients. The clinical and biochemical variables were analyzed for correlation with specific histologic features. RESULTS: Twenty-six patients (25%) were found to have nonalcoholic steatohepatitis (NASH), and 11 (42%) of these had advanced fibrosis. A raised index of insulin resistance (odds ratio [OR] 9.3, 95% confidence interval [CI] 3.4-26), systemic hypertension (OR 5.2, 95% CI 2.0-13.5), and raised alanine aminotransferase (OR 8.6, 95% CI 3.1-23.5) were independent predictors of NASH. A combination of 2 or 3 of these predictors allows a sensitivity of 0.8 and specificity of 0.89 for NASH. Alcohol consumption was associated with a reduction in NASH (OR 0.35, 95% CI 0.12-1.00) and diabetes (OR 0.18, 95% CI 0.047-0.67). CONCLUSION: Insulin resistance and systemic hypertension, features of the metabolic syndrome, are independently associated with advanced forms of NAFLD. Moderate alcohol consumption seems to reduce the risk of NAFLD in the severely obese, possibly by reducing insulin resistance.


Subject(s)
Fatty Liver/etiology , Fatty Liver/pathology , Obesity, Morbid/complications , Adult , Body Mass Index , Cholesterol/blood , Fatty Liver/surgery , Female , Humans , Hypertension/complications , Insulin Resistance , Laparoscopy , Liver Cirrhosis/etiology , Male , Predictive Value of Tests , Prospective Studies , Risk Factors
10.
Liver ; 21(2): 149-58, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11318985

ABSTRACT

BACKGROUND/AIMS: Growth hormone (GH), when overexpressed in male and female GH-transgenic mice, is known to induce liver tumours within 1 year. This study aimed to gain a clearer understanding of the interaction between GH and tumour cells in vivo. METHODS/RESULTS: The carcinogen diethylnitrosomine (DEN) was administered to neo-natal transgenic and non-transgenic mice maintained in a "hepatocarcinogenesis resistant" genetic background (C57BL/6J). Macroscopic, microscopic and liver weight/body weight ratio analyses revealed that carcinogen-induced hepatocarcinogenesis was dramatically accelerated in young GH-transgenic mice compared to non-transgenic counterparts. Image analysis of microscopic hepatocellular neoplasms showed rapidly increasing tumour burdens, and neoplastic foci size over time in young adult GH-transgenic mice. The magnitude of enhanced tumour growth was equivalent in both male and female transgenic mice, whereas much lower and sexually dimorphic tumour growth rates (males>females) were observed in non-transgenic mice treated with DEN. BrdU labelling experiments demonstrated that rapid tumour growth in carcinogen-treated GH-transgenic mice was due to the promotion of cell proliferation in emerging lesions. Tumour cell proliferation in young GH-transgenic mice was 2.6- and 4-fold higher, respectively, than that observed in similar age male and female non-transgenic mice. Interestingly, both GH-transgenic and non-transgenic mice displayed progressively slower tumour growth rates in older animals. CONCLUSION: Overall, GH synergistically promotes carcinogen-induced hepatocarcinogenesis in both sexes of GH-transgenic mice by stimulating tumour cell proliferation.


Subject(s)
Focal Nodular Hyperplasia/metabolism , Growth Hormone/biosynthesis , Liver Neoplasms, Experimental/metabolism , Precancerous Conditions/metabolism , Animals , Animals, Newborn , Apoptosis , Bromodeoxyuridine/analysis , Bromodeoxyuridine/metabolism , Cell Division/drug effects , Diethylnitrosamine/toxicity , Female , Focal Nodular Hyperplasia/chemically induced , Focal Nodular Hyperplasia/genetics , Focal Nodular Hyperplasia/pathology , Growth Hormone/genetics , Image Processing, Computer-Assisted , Immunoenzyme Techniques , In Situ Nick-End Labeling , Liver/chemistry , Liver/drug effects , Liver/pathology , Liver Neoplasms, Experimental/chemically induced , Liver Neoplasms, Experimental/genetics , Liver Neoplasms, Experimental/pathology , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Organ Size/drug effects , Precancerous Conditions/chemically induced , Precancerous Conditions/genetics , Precancerous Conditions/pathology , Time Factors
11.
Pathology ; 33(1): 44-9, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11280607

ABSTRACT

Iron overload has been proposed as a cause of liver dysfunction after BMT Factors which could be relevant to iron overload include the number of red cell transfusions and mutations within the haemochromatosis gene (HFE). Two point mutations, Cys282Tyr and His63Asp, have been described within HFE. Cys282Tyr homozygosity is associated with haemochromatosis; the effect of compound heterozygosity, Cys282Tyr/His63Asp, on iron status is variable. We analysed HFE status in 52 allograft patients surviving more than 6 months. Compound heterozygosity was identified in three patients (Cases 1-3). Iron status and liver function were evaluated and, in Cases 1 and 2, liver histology and iron content as well. Case 3 who received 12 units of red cells had a normal ferritin and liver function. Cases 1 and 2 received 29 and 59 units, respectively, and had high serum ferritins and transferrin saturations, abnormal liver function and significant hepatic iron overload on biopsy. Iron overload in Case 1 patient progressed in the context of GVHD and in the absence of further transfusion, suggesting that liver GVHD may increase hepatic iron accumulation. These cases demonstrate the variable phenotypic expression of HFE compound heterozygosity in BMT recipients, which may be only partly explained by transfusional iron loading. Venesection or chelation therapy should be considered in patients with coexistent hepatic GVHD and iron overload.


Subject(s)
Bone Marrow Transplantation/adverse effects , Hemochromatosis/genetics , Iron Overload/genetics , Liver Diseases/genetics , Loss of Heterozygosity , Mutation , Adult , DNA/analysis , Female , Graft vs Host Disease/blood , Graft vs Host Disease/etiology , Graft vs Host Disease/genetics , Graft vs Host Disease/pathology , Hemochromatosis/etiology , Hemochromatosis/metabolism , Hemochromatosis/pathology , Humans , Iron/metabolism , Iron Overload/complications , Iron Overload/pathology , Liver/metabolism , Liver/pathology , Liver Diseases/blood , Liver Diseases/etiology , Liver Diseases/pathology , Liver Function Tests , Male , Middle Aged , Polymerase Chain Reaction , Transplantation, Homologous
12.
Ann Rheum Dis ; 60(1): 69-71, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11114287

ABSTRACT

Cogan's syndrome is a rare, multisystem disease which occurs predominantly in children and young adults. It was originally described as the combination of interstitial keratitis and audiovestibular disturbance, but other forms of ocular disease, as well as systemic vasculitis, have since been recognised as part of the syndrome. Diagnosis can be difficult if the various manifestations occur separately, but early recognition is important because prompt treatment may prevent deafness. Two cases are presented here illustrating the features of this disease, and providing histological evidence of systemic vasculitis in both.


Subject(s)
Hearing Loss, Sensorineural/diagnosis , Vasculitis/diagnosis , Adult , Glucocorticoids/therapeutic use , Hearing Loss, Sensorineural/drug therapy , Humans , Iritis/diagnosis , Iritis/drug therapy , Male , Prednisolone/therapeutic use , Syndrome , Vasculitis/drug therapy
13.
Histochem Cell Biol ; 114(2): 125-35, 2000 Aug.
Article in English | MEDLINE | ID: mdl-11052261

ABSTRACT

The monoclonal antibody 5HL-5D11-D10 to antigen D10 identifies a cell lineage that is restricted to certain tissues of the human foregut. We investigated the tissue distribution of antigen D10 in mammals, birds, reptiles, amphibians and fish by immunohistochemical staining. Tissue from human and each of ten other mammalian species showed staining of gastric mucous neck cells and glands of the cardia and antrum, Brunner's glands, peribiliary glands and periductal glands of the pancreas. Six of the mammalian species also expressed antigen D10 in mucosa of the larger bronchi, and five expressed it to varying degree in small bowel distal to the duodenum and in colon (three of these five species). Antigen was not detected in any of the three species of bird studied. Both reptiles and amphibians showed strong staining for antigen D10 in the gastric mucous neck cells and pyloric glands, and in a subpopulation of secretory cells in the oesophagus, with the amphibian also expressing antigen in some epithelial cells of the mouth and lung. Although absent from two species of bony fish, antigen D10 was expressed by small groups of epithelial cells of the intestine of a shark, and generally by the epithelial and connective tissue cells of the gut and gills, and hepatocytes of one species of ray. The presence of antigen D10 in different tissues and species was confirmed by both an indirect ELISA and immunoblot analysis of tissue extracts. Our observations suggest that the D10 epitope characterises a subpopulation of mucus-secreting cells, predominantly of the foregut and associated organs, which has been conserved throughout terrestrial vertebrate evolution.


Subject(s)
Antigens/analysis , Digestive System/chemistry , Animals , Anura , Cats , Cattle , Cell Lineage , Dogs , Enzyme-Linked Immunosorbent Assay/methods , Haplorhini , Humans , Immunoblotting/methods , Macropodidae , Mice , Phylogeny , Rabbits , Rats , Reptiles , Sheep , Subcellular Fractions , Swine , Tissue Extracts
15.
Liver ; 20(1): 16-26, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10726957

ABSTRACT

BACKGROUND/AIMS: Graft versus host disease (GVHD) following histoincompatible bone marrow transplantation may be modelled experimentally using irradiated metallothionein promoter-H-2Kb transgenic mice (MET-Kb mice), reconstituted with syngeneic non-transgenic spleen and lymph node (LN) cells. In this model, inflammation peaks at 3 weeks post-reconstitution, but resolves by 3 months, and is focussed on portal tracts and bile ducts (BD). The aim of this study was to determine if transgene-expressing hepatocytes play a role in the immune response, why portal tracts are selectively targeted, and which cell types are involved. METHODS: Intrahepatic BD (IHBD) with attached hepatocytes, or extrahepatic BD (EHBD) devoid of hepatocytes, were isolated from MET-Kb mice and implanted under the kidney capsule of transgenic (syngeneic) and congenic (allogeneic) mice. Three weeks post-implantation, BD were scored histologically for rejection or survival, and stained for various cell-surface molecules. RESULTS: Generally, IHBD survived better than EHBD, and T cells were the predominant infiltrating cell type in both implants. Both types of implants undergoing rejection expressed intercellular adhesion molecule-1 (ICAM-1) and leukocyte function antigen-1 (LFA-1) at high density; BD and the underlying kidney parenchyma also expressed class I and II major histocompatibility complex (MHC). CONCLUSIONS: The rejection of both groups of implants by congenic recipients suggests that BD from MET-Kb mice express the transgene, but the reason for the selective targeting of portal tracts rather than transgene-expressing hepatocytes remains unclear. One possible explanation is that dendritic cells/antigen-presenting cells (DC/APC) in portal tracts, which express high levels of MHC and co-stimulatory molecules, are the primary targets, and that BD are infiltrated and destroyed as 'bystanders'.


Subject(s)
Bile Ducts, Extrahepatic/transplantation , Bile Ducts, Intrahepatic/transplantation , Graft vs Host Disease/etiology , Kidney/surgery , Animals , Bile Ducts, Extrahepatic/metabolism , Bile Ducts, Extrahepatic/pathology , Bile Ducts, Intrahepatic/metabolism , Bile Ducts, Intrahepatic/pathology , CD4-Positive T-Lymphocytes/pathology , CD8-Positive T-Lymphocytes/pathology , Graft Rejection/etiology , Graft Rejection/metabolism , Graft Rejection/pathology , Graft vs Host Disease/metabolism , Graft vs Host Disease/pathology , H-2 Antigens/metabolism , Histocompatibility Antigens Class I/metabolism , Histocompatibility Antigens Class II/metabolism , Immunoenzyme Techniques , Intercellular Adhesion Molecule-1/metabolism , Lymphocyte Function-Associated Antigen-1/metabolism , Mice , Mice, Transgenic
16.
Liver ; 19(3): 242-52, 1999 Jun.
Article in English | MEDLINE | ID: mdl-10395045

ABSTRACT

AIMS/BACKGROUND: Growth hormone (GH) transgenic mice are known to develop hepatocellular adenomas and carcinomas. In order to understand more about hepatocarcinogenesis in the GH-transgenic mouse model we quantitated the rates of hepatocellular proliferation and apoptosis in these mice. METHODS: Two lines of GH-transgenic mice and non-transgenic control mice were generated and sacrificed at regular intervals between one and nine months. Hepatocellular replication was measured by in vivo incorporation of bromodeoxyuridine (BrdU) and counting BrdU-positive nuclei in histological liver sections. Serial sections taken from these mouse livers were also assessed for rates of hepatocellular apoptosis using the in situ end-labelling of fragmented DNA (TUNEL) method. RESULTS: High levels of hepatocellular replication were sustained life-long in this model. Increased rates of hepatocellular proliferation preceded the onset of hepatic inflammation, a prominent feature in the liver pathology of GH-transgenic mice. In tumour tissue, cellular proliferation was up to 17-fold greater than in surrounding non-tumour tissue. Apoptosis rates were also elevated in non-tumour regions of GH-transgenic mouse livers compared to controls. Interestingly, large dysplastic hepatocytes were common in the fraction of cells undergoing apoptosis, especially in older mice with inflamed livers. The increase in the rate of hepatocellular apoptosis in GH-transgenic animals largely balanced the augmented levels of proliferation seen in these mice. In tumour tissue, however, the profound increase in the number of proliferating tumour cells outstripped the increase in apoptosis. CONCLUSION: Relatively high and enduring levels of hepatocellular replication and apoptosis precede hepatocarcinogenesis in GH-transgenic mice. Increased cellular proliferation and resistance to apoptosis were evident in tumour growth in older animals.


Subject(s)
Growth Hormone/genetics , Liver/pathology , Adenoma/pathology , Age Factors , Animals , Apoptosis , Body Weight/genetics , Carcinoma, Hepatocellular/pathology , Cell Division/genetics , Female , Growth Hormone/biosynthesis , In Situ Nick-End Labeling , Liver/anatomy & histology , Liver Neoplasms, Experimental/pathology , Male , Metallothionein/genetics , Mice , Mice, Inbred C57BL , Mice, Transgenic , Mitotic Index/genetics , Organ Size/genetics
17.
J Gastroenterol Hepatol ; 13(10): 1058-60, 1998 Oct.
Article in English | MEDLINE | ID: mdl-9835324

ABSTRACT

Sublethal injury of the liver with carbon tetrachloride (CCl4) induces the modulation of hepatic stellate cells to their myofibroblast (MFB) phenotype. Pretreatment or concomitant treatment with interferon gamma (IFNgamma) has been shown to inhibit this phenomenon. The aim of this study was to investigate the influence of IFNgamma treatment (50000 IU s.c. each day for 5 days) in rats with an established cirrhosis. Cirrhosis was induced with nine doses of CCl4. Comparison of biopsies before and after treatment with IFNgamma showed that the number of MFB present, identified by their alpha-smooth muscle actin immunoreactivity, was markedly reduced. Pressure-flow curves were constructed in isolated perfused liver preparations from IFNgamma-treated and saline-treated cirrhotic rats and analysed to obtain the extrapolated zero-flow intercept (Po, an index of hepatic vascular distensibility) and the vasodilator-induced change in resistance at a flow rate of 1 mL/min per g (deltaR1, an indication of the level of intrinsic vascular tone). In IFNgamma-treated rats, portal venous pressure measured in vivo was significantly reduced compared with controls (11.9+/-1.2 vs 16.0+/-0.5 mmHg, P< 0.05), Po was lower (2.03+/-0.18 vs 2.87+/-0.32 mmHg, P<0.05) and deltaR1 was decreased (0.39+/-0.15 vs 1.02+/-0.19 mmHg/mL per min per g, P< 0.05). The findings indicate that treatment with IFNgamma is effective in reducing MFB density in established CCl4-cirrhosis in the rat and results in a marked improvement in intrahepatic haemodynamics.


Subject(s)
Interferon-gamma/therapeutic use , Liver Circulation/physiology , Liver Cirrhosis, Experimental/therapy , Animals , Carbon Tetrachloride Poisoning , Hypertension, Portal/pathology , Hypertension, Portal/physiopathology , Hypertension, Portal/therapy , Liver/pathology , Liver Cirrhosis, Experimental/chemically induced , Liver Cirrhosis, Experimental/physiopathology , Male , Portal Pressure/physiology , Rats , Rats, Wistar , Recombinant Proteins
18.
Hepatology ; 27(2): 446-51, 1998 Feb.
Article in English | MEDLINE | ID: mdl-9462643

ABSTRACT

The influence of hepatocyte enlargement on intrahepatic hemodynamics was assessed in the isolated perfused rat liver preparation (IPRL) using two experimental models: hypotonic liver cell swelling and phenobarbitone-induced hepatocyte hypertrophy. The analysis of pressure-flow data obtained from the portal vascular bed over a flow range of 0 to 70 mL/min in the presence of a maximally-effective concentration of the vasodilator agent papaverine hydrochloride (6 x 10(-4) mol/L) enabled the calculation of P0, an estimate of the pressure required to passively distend the intrahepatic vasculature, and Gmax, the maximal portal vascular conductance. By comparison with an isotonic perfusion medium (Krebs-Henseleit buffer [KH] containing 2.5% bovine serum albumin [BSA]), perfusion with a hypotonic medium induced a significant increase in mean hepatocyte cross-sectional area (H(A)) (590 +/- 21 vs. 324 +/- 23 microm(-2), p < .05), a fall in Gmax (0.39 +/- 0.08 vs. 2.02 +/- 0.18 mL/min/g/mm hg, P < .001), and an increase in P0 (2.96 +/- 0.38 vs. 1.58 +/- 0.07 mm hg, P < .001). Phenobarbitone administered in drinking water (0.5 g/L) over a period of 60 days also induced a significant degree of hepatocyte enlargement (HA, 510 +/- 29 microm2, P < .05). On day 7, portal pressure measured in vivo in this group was significantly elevated compared with untreated controls (10.5 +/- 0.3 vs. 8.4 +/- 0.2 mm hg, P < .001), while in the IPRL Gmax was reduced (0.48 +/- 0.01 mL/min/g/mm hg, P < .001), and P0 was increased (2.23 +/- 0.17 mm hg, P < .05). However, with continued phenobarbitone treatment portal pressure, Gmax and P0 returned toward control values. The results confirm that hepatocyte enlargement is associated with a significant disturbance of intrahepatic hemodynamics but also that some adaptation occurs if hepatocyte enlargement is sustained over a prolonged period of time.


Subject(s)
Liver Circulation/physiology , Animals , Body Weight , Dose-Response Relationship, Drug , Hypertrophy/chemically induced , Hypertrophy/physiopathology , Hypotonic Solutions , In Vitro Techniques , Liver/blood supply , Liver/pathology , Liver/physiopathology , Liver Circulation/drug effects , Male , Organ Size/drug effects , Papaverine/pharmacology , Phenobarbital/pharmacology , Portal Pressure/drug effects , Rats , Rats, Wistar , Time Factors
19.
J Clin Pathol ; 50(9): 741-8, 1997 Sep.
Article in English | MEDLINE | ID: mdl-9389974

ABSTRACT

AIM: To investigate the phenotype of cells comprising diffuse and intestinal-type gastric cancers using monoclonal antibodies to two antigens. One antigen (designated D10) is characteristic of gastric mucous neck cells, cardiac glands, pyloric glands, and Brunner's glands. The second antigen (designated 17NM) is specific to the mucous vacuole of intestinal goblet cells. METHODS: Thirty two gastrectomy specimens with adenocarcinoma were studied. Serial paraffin sections were stained immunohistochemically for D10 and 17NM and histochemically for acid and neutral mucins. The cancers were classified histologically as of either diffuse or intestinal type according to Lauren. RESULTS: Of 15 diffuse-type gastric carcinomas, 11 showed the majority of cancer cells staining for D10 while four were typical signet ring cell cancers staining predominantly for 17NM; five tumours displayed both phenotypes with the two phenotypes segregated in different areas of the tumours. In contrast, of 16 intestinal-type cancers, six expressed 17NM, three D10, five neither antigen, and two expressed both antigens. One indeterminate-type cancer expressed both antigens. The staining of individual cells for D10 and 17NM was mutually exclusive in both diffuse and intestinal types. In contrast to the diffuse cancers, intestinal-type cancers typically expressed either antigen only in occasional small groups of cells and individual cells. CONCLUSIONS: In disease, the gastric stem cell can assume the capacity of the duodenal stem cell for divergent differentiation into either intestinal goblet cells (for example, as in intestinal metaplasia) or Brunner's gland cells (for example, as in pyloric gland/Brunner's gland metaplasia). With neoplastic transformation, this potential for divergent differentiation is maintained and gives rise to diffuse-type cancers that display either the D10 phenotype, the 17NM phenotype, or the clonal expression of both phenotypes. In the more cell cohesive (intestinal-type) tumours, differentiation for antigen expression is poorly developed and more frequently directed towards the intestinal goblet cell phenotype.


Subject(s)
Adenocarcinoma/pathology , Stomach Neoplasms/pathology , Adenocarcinoma/chemistry , Adult , Aged , Aged, 80 and over , Antibodies, Monoclonal , Antigens, Neoplasm/analysis , Female , Humans , Immunoenzyme Techniques , Immunophenotyping , Male , Middle Aged , Phenotype , Stomach Neoplasms/chemistry
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