Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0023890 (cirrhosis)
 42,195 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The modifying action of chronic liver injury on the process of hepatocarcinogenesis was investigated. To induce cirrhosis or fibrosis F344 rats received CCl4 alone or in combination with phenobarbital, either before (model 1) or after (model 2) the application of initiator, diethylnitrosamine (DENA). In these models, morphology, tumor incidence as well as polysubstrate monooxygenase system, gamma-glutamyltransferase (GGT) and glucose-6-phosphatase (G-6-Pase) were studied. The data presented show that in model 1 the tumor incidence was much lower than in rats treated with DENA alone. This reduction appeared to be associated with the decrease in cytochrome P450 content occurring in model 1 after DENA administration. Promotion of the hepatocarcinogenic process was observed when CCl4 injury followed the application of DENA (model 2). Comparison of marker enzymes in cirrhotic livers and in tumors either with or without cirrhosis indicated that changes in cytochrome P450 and G-6-Pase were rather the results of parenchymal damage, while GGT was elevated only in tumorous livers. In tumorous livers none of the xenobiotic metabolizing activities decreased as much as the cytochrome P450 content of the same samples. Thus conceivably the cytochrome P450 operates more rapidly in tumors than in normal livers.
Carcinogenesis 1992 May
PMID:Modification of DENA-induced hepatocarcinogenesis by CCl4 cirrhosis. Comparison of the marker enzyme patterns. 135 Feb 34

The modifying effects of an immunosuppressive agent, 6-mercaptopurine (6-MP), on development of focal lesions in liver cirrhosis models induced by carbon tetrachloride (CCl4) or furfural were studied in male F344 rats. Feeding of 6-MP at 50 p.p.m. for 20 weeks to animals with pre-existing liver cirrhosis caused immunosuppression, and significantly enhanced the induction of gamma-glutamyltranspeptidase (GGT)-positive foci and nodules in the CCl4 but not furfural case. Glutathione S-transferase P (GST-P)-positive preneoplastic lesions were not affected. Moreover, phenobarbital (PB) also enhanced the induction of GGT-positive hepatocellular lesions only in the CCl4-induced liver cirrhosis model, no promotion influence being exerted after treatment with the non-carcinogenic furfural. This study, therefore, suggests that 6-MP can enhance the induction of one type of preneoplastic foci and nodules and that essential differences exist between focal lesions arising in cirrhotic livers caused by CCl4 as opposed to furfural.
Carcinogenesis 1992 Aug
PMID:Possible enhancing effect of the immunosuppressive agent, 6-mercaptopurine(6-MP) on focal lesion development in cirrhotic liver induced by carbon tetrachloride but not furfural in F344 rats. 135 82

To clarify the physiologic response of splenic lymphocytes to liver damage and the role of this response in regeneration versus malignant transformation, we cultured rat spleen lymphocytes with portal sera from rats subjected either to partial (70%) hepatectomy or to long-term oral administration of the hepatic carcinogen 3'-methyl-4-dimethylaminoazobenzene. Sera taken within 24h after partial hepatectomy contained a previously described signal protein which serves as a marker of liver damage. The MW 5,000-10,000 serum fraction also contained a factor that promoted cell growth, DNA synthesis, glucose utilization, and the production of anti-sheep erythrocyte plaque-forming cells in cultures of rat splenic lymphocytes. In contrast, the sera of rats subjected to liver damage by the carcinogen had no more effect on the cultured lymphocytes than sera from sham-operated or untreated controls. The signal protein was present initially in portal sera from carcinogen-treated rats, but decreased as hepatitis gave way to cirrhosis. Subsequent malignant transformation was marked by the appearance of serum alpha-fetoprotein. Our results suggest that activation of splenic lymphocytes by serum factor(s) is involved in hepatic regeneration and that this process is deranged in carcinogenesis.
 ...
PMID:In-vitro immune response of splenic lymphocytes to portal serum agents from rats undergoing hepatic regeneration or hepatic carcinogenesis. 139 18

A semi-purified corn-based diet containing 50 mg/kg of pure (not less than 90%) fumonisin B1 (FB1), isolated from culture material of Fusarium moniliforme strain MRC 826, was fed to a group of 25 rats over a period of 26 months. A control group of 25 rats received the same diet without FB1. Five rats from each group were killed at 6, 12, 20 and 26 months. The liver was the main target organ in the FB1-treated rats and the hepatic pathological changes were identical to those previously reported in rats fed culture material of F.moniliforme MRC 826. All FB1-treated rats that died or were killed from 18 months onwards suffered from a micro- and macronodular cirrhosis and had large expansile nodules of cholangiofibrosis at the hilus of the liver. Ten out of 15 FB1-treated rats (66%) that were killed and/or died between 18 and 26 months developed primary hepatocellular carcinoma. Metastases to the heart, lungs or kidneys were present in four of the rats with hepatocellular carcinoma. No neoplastic changes were observed in any of the control rats. Chronic interstitial nephritis was present in the kidneys of FB1-treated rats killed after 26 months. No lesions were observed in the esophagus, heart or forestomach of FB1-treated rats and this is contrary to previous findings when culture material of the fungus was fed to rats. It is concluded that FB1 is responsible for the hepatocarcinogenic and the hepatotoxic but not all the other toxic effects of culture material of F.moniliforme MRC 826 in rats.
Carcinogenesis 1991 Jul
PMID:Toxicity and carcinogenicity of the Fusarium moniliforme metabolite, fumonisin B1, in rats. 164 15

Despite the epidemiological evidence of a correlation between ethanol abuse and hepatocellular carcinoma, some of the results of experimental and clinical studies remain controversial. Apart from inducing cirrhosis, which may be viewed as a precancerous liver lesion, ethanol may act as a cocarcinogen. Most investigations on this topic have focused on two aspects: ethanol's capacity to induce the cytochrome P-450-dependent microsomal biotransformation system and its interference with at least one DNA repair mechanism. Ethanol exposure enhances the capacity of mixed function oxidases to activate many chemical carcinogens, such as dimethylnitrosamine (DMN). On the other hand, ethanol exposure fails to influence DMN-induced liver carcinogenesis. The capacity of alcohol to inhibit DMN-demethylase activity has not been clearly demonstrated in experiments carried out with human tissue. In conclusion, both the effects of ethanol and their underlying mechanisms as regards liver carcinogenesis are open to debate. The link between ethanol abuse and hepatocellular carcinoma appears to be mediated mainly by its capacity to induce cirrhosis.
 ...
PMID:Hepatocellular carcinoma, alcohol, and cirrhosis: facts and hypotheses. 165 Jun 91

A recently introduced enzyme immunoassay procedure for antibodies against the hepatitis-C virus (HCV) was used to test samples from 185 cases with hepatocellular carcinoma (HCC) and 432 hospital controls. The anti-HCV results were examined in conjunction with previously reported data from this study concerning hepatitis-B virus (HBV) serology, hepatitis-D virus (HDV) antibodies, presence of cirrhosis and tobacco smoking. There was evidence for interaction between HBV and HCV in the causation of HCC: as previously reported, the rate ratio (RR) linking the presence of anti-HCV to HCC among subjects positive for hepatitis-B surface antigen (HBsAg) was substantially higher than the corresponding RR among those negative for this marker; furthermore, among HCC patients positive for HBsAg, a high proportion (33/61) of those who were positive for hepatitis-Be antigen (HBeAg) or its antibody were positive for anti-HCV, whereas among HBsAg-positive controls who were also positive for HBeAg or its antibody, none was positive for anti-HCV (0/18; p less than 10(-4)). The anti-HCV-related RR for HCC was also higher among HCC patients with cirrhosis than among those without evidence of co-existing cirrhosis (RR 11.4 vs. 4.4; p = 0.06). In addition, there was some evidence of interaction between tobacco smoking and HCV in the origin of HCC; after controlling for age, sex and HBsAg status, the RR for subjects positive for anti-HCV was 6.8 among smokers but only 3.2 among non-smokers (p = 0.26). By contrast, there was no suggestion of an interaction between anti-HCV and anti-HDV, in agreement with the presumed minimal role, if any, of HDV in HCC etiology. These results support the notion that HCV is involved in the etiology of HCC by advancing, through a chronic liver disease process, carcinogenesis initiated by other factors.
 ...
PMID:Epidemiologic assessment of interactions of hepatitis-C virus with seromarkers of hepatitis-B and -D viruses, cirrhosis and tobacco smoking in hepatocellular carcinoma. 165 59

The etiologic relationship of hepatocellular carcinoma (HCC) and chronic hepatitis B viral infection was proved clinically, epidemiologically, virologically, serologically and by other methods. Together with viruses, carcinogenesis is promoted by faster recovery of hepatocytes (liver cirrhosis, chronic hepatitis, etc.). We have discovered 103 HCC in the period of 21 years. There were 81 men and 22 women; they were in the sixth and seventh decade of life in 90% of cases. Liver cirrhosis was also confirmed in 55% of cases and chronic hepatitis in 19%, namely, in 74% of patients HCC has developed on the changed liver. Fifty three patients were HBsAg positive (51.45%). The ultrasound and determination of alpha-feto proteins proved to be most valuable. It is a slow growing tumour and by its early detection surgical treatment is possible.
 ...
PMID:[Hepatocellular carcinoma--retrospective analysis]. 166 95

We produced monoclonal antibodies (mABs) against human integrins. Competitive enzyme-linked immunosorbent assay (ELISA) revealed that each mAB bound to different antigenic determinants. We then developed sandwich-type enzyme immunoassays (EIAs) to measure the concentration of fibronectin receptor (FNR) and vitronectin receptor (VNR). Serum immunoreactive integrin levels were measured using these EIAs in various liver and malignant diseases. In almost all cases of liver cirrhosis (LC) and hepatocellular carcinoma (HCC), serum integrin levels were significantly elevated, but were in the normal range in gastric, colon, lung cancer, and acute hepatitis (AH). The correlation between serum FNR and VNR levels was statistically significant in all cases of liver disease, and no correlation was observed between these integrin levels and conventional biochemical markers such as AST, ALT, and GGT. The serum integrin levels were demonstrated to be a potential diagnostic marker for hepatic fibrogenesis and carcinogenesis, and these sandwich EIAs could be useful for determination of these integrins in clinical laboratory tests.
 ...
PMID:Sandwich enzyme immunoassay for serum integrins using monoclonal antibodies. 172 78

The expression of cellular oncogenes in nonneoplastic human liver tissue was examined to determine if there was a correlation between oncogene expression and physiologic regeneration in liver disease. Human liver tissue specimens from 70 patients with various histologic findings from almost normal to cirrhosis were examined (using northern blot analysis) for the expression of nine cellular oncogenes. With c-K-ras, four RNA bands (5.6-kilobase [kb], 2.1-kb, 1.5-kb, and 1.2-kb RNA species) were detected in all liver tissue examined. Expression of c-fos was also detected in a few samples examined when 50-micrograms samples of total RNA were applied. Other oncogenes such as H-ras, myc, erbB, raf, fms, fes, and myb were not detected. These results indicate that particular oncogene(s) may not be highly expressed during liver regeneration in human liver disease, or that populations of regenerating hepatocytes may be too small to show significant elevations of oncogene expression. The new finding of a constant expression of c-K-ras in human liver tissue suggests that it is linked to essential hepatocellular function rather than carcinogenesis.
 ...
PMID:Oncogene expression in the liver tissue of patients with nonneoplastic liver disease. 201 59

Until the end of August 1988, 158 patients with hepatocellular carcinoma underwent curative hepatic resection in our department. One-hundred and twenty-one patients (77%) had liver cirrhosis (Group A), and the remaining 37 (23%) did not (Group B). Background factors and postoperative courses were compared between Group A and Group B. With regard to clinical stage and curability, there were no significant differences between the two groups. On postoperative follow-up on 1- to 5-year survival, no differences were recognized between the two groups, but on and after 6-year survival, the former were significantly worse than the latter. The main cause of death was cancer in both groups. In group B, all intrahepatic recurrences happened within 3 years after surgery. On the other hand, intrahepatic recurrences of Group A were also found on postoperative 4- and 5-year to be as numerous as the recurrences found at 1-, 2- and 3-year after surgery. Moreover, with recurrent cases on and after 4 years in Group A, the frequency of solitary focus was high. The differences of postoperative courses between these two groups might be caused by metachronous carcinogenesis of cirrhotic liver.
 ...
PMID:[Long-term postoperative courses of hepatocellular carcinoma with and without cirrhosis]. 215 65


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>