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161.
Reduction of hepatocarcinogenesis by ursodeoxycholic acid in rats   总被引:7,自引:0,他引:7  
Ursodeoxycholic acid (UDCA) is used worldwide for treatment of primary biliary cirrhosis and chronic liver diseases. However, its action on hepatocarcinogenesis remains to be explored. To clarify its effect, in vivo and in vitro experiments were performed. Ninety Fisher 344 rats were fed a standard diet (Group 1, n = 30), a standard diet supplemented with 0.1% UDCA (Group 2, n = 30) and 0.3% UDCA (Group 3, n = 30). The rats were given an i.p. injection of diethylnitrosamine (DEN) weekly for 6 weeks. Fifteen additional rats were fed 0.3% UDCA supplemented diet without DEN treatment (Group 4). The rats were killed at 5, 10 and 18 weeks after the last injection of DEN. The number of liver tumor and percentage of the GST-P-positive hepatocytes were significantly reduced by UDCA treatment. The PCNA-positive cells were decreased by administration of UDCA at 18 weeks. The increased number of apoptotic cells was observed in the GST-P-negative area at 5, 10 and 18 weeks and in the GST-P-positive area at 18 weeks in the UDCA group. Expression of Bax in mitochondria and cytochrome c in cytosol was increased by UDCA treatment. Caspase 3 activity was also increased in the UDCA groups. The addition of UDCA into the culture of Huh7 and Fao hepatocellular carcinoma (HCC) cells induced apoptosis in a dose-dependent manner. The data of the present study suggest that UDCA treatment reduces hepatocarcinogenesis via inducing apoptosis of 'initiated hepatocytes' as well as inhibiting proliferation.  相似文献   
162.
Measurements of serum concentrations of free T4, T3, TSH, and thyroglobulin (Tg) were conducted in 42 infants (2-9 months of age) detected and treated through the Northwest Newborn Regional Screening Program and 63 children and adolescents (1-18 yr of age) with congenital hypothyroidism (CH) detected and managed in the Northern California Kaiser Permanente Medical Care Program. Normal feedback control axis data were developed by Quest Diagnostics, Inc. - Nichols Institute Diagnostics and Loma Linda University, from free T4 and TSH measurements in 589 healthy subjects, 2 months to 54 yr of age; 83 untreated hypothyroid patients; and 116 untreated hyperthyroid patients. Twenty-four of the 42 CH infants and 57 of the 63 CH children manifested serum TSH concentrations appropriate for the measured free T4 level. In the remaining 18 infants and 6 children, serum free T4 values were increased 0.2-1.4 ng/dL (2.6-18.0 pmol/L) for the prevailing TSH level, suggesting a state of mild to moderate pituitary-thyroid hormone resistance. In the treated children, the mean T3 concentration was lower (by 32%, 102 vs. 150 ng/dL; 1.57 vs. 2.31 nmol/L) than in normal children, in agreement with earlier data in hypothyroid adults treated with exogenous T4. Serum Tg concentrations were normal or elevated in 90% of the 19 children with ectopic glands and 93% of 27 children with eutopic glands in whom measurements were available. There was a positive correlation between serum TSH and Tg concentrations (P < 0.001), suggesting significant endogenous thyroid hormone production in these children. Our results suggest that the majority of infants and children with CH have a normal hypothalamic-pituitary-thyroid negative feedback control axis during treatment and that the measurement of serum TSH is a useful marker complementing the free T4 measurement in the management of children with CH. A minority have variable pituitary-thyroid hormone resistance, with relatively elevated serum TSH levels for their prevailing serum free T4 concentration. The prevalence of resistance is greater (43%) in young infants (< 1 yr of age) than in older children (10%), indicating that, in most children, the resistance improves with age.  相似文献   
163.
Oxidative stress plays an important role in hepatocarcinogenesis. Although Sho-saiko-to (TJ-9), a Japanese herbal medicine which has been recently administered to patients with chronic liver disease in Japan, prevents hepatocarcinogenesis, the mechanism by which TJ-9 protects against cancer development is not fully understood. 8-Hydroxy-2'-deoxyguanosine (8-OHdG), a DNA adduct by reactive oxygen species, is known as a parameter of genetic risk for hepatocarcinogenesis. To clarify whether the preventive effect on hepatocarcinogenesis by TJ-9 is dependent on 8-OHdG, the effect on 8-OHdG levels by TJ-9 was examined by using high-performance liquid chromatography-mass spectrometry (LC-MS) in a diethylnitrosamine (DEN)-induced hepatocarcinogenesis model of male Fisher rats. TJ-9 reduced the number of preneoplastic cells, detected as the glutathione S transferase P (GST-P)-positive hepatocytes, and inhibited the development of liver tumors. TJ-9 also significantly decreased the formation of 8-OHdG, as indicated by LC-MS and immunohistochemical analysis. In addition, ornithine decarboxylase (ODC) activity and the number of proliferating cell nuclear antigen (PCNA)-positive cells were not altered. An electron paramagnetic resonance spin-trapping technique showed that TJ-9 scavenges hydroxyl radicals in a dose-dependent manner. In conclusion, the results of the present study suggest that TJ-9 prevents hepatocarcinogenesis in association with inhibition of 8-OHdG formation.  相似文献   
164.

Background

Definitive chemoradiotherapy (CRT) is used to treat lymph node metastatic head and neck cancer patients. Regional control of the neck disease is important to improve the prognosis, and the accuracy of the method used to evaluate the metastatic lymph node(s) after CRT is crucial to the decision-making process for any following salvage surgery.

Methods

Patients undergoing CRT were divided in two groups of patients of those showing complete clinical response (CR) and those showing clinical non-response (non-CR), as assessed by computed tomography (CT) and/or magnetic resonance imaging (MRI), ultrasonography, fluorodeoxyglucose-positron emission tomography (FDG-PET), and fine needle aspiration cytology. The responses (CR vs. non-CR) were compared with the actual clinical outcomes. For the interim analysis, the study period was broken down into two periods, namely, the exploratory phase (patients treated between January 2002 and April 2012) and the validating phase (patients treated between May 2012 and January 2014).

Results

The sensitivity, specificity, and accuracy were as follows: CT and/or MRI, 66.7, 73.8, and 72.8 %, respectively, in the exploratory phase; ultrasonography, 91.7, 70.6, and 73.4 %, respectively, in the exploratory phase and 80.0, 82.8, and 82.4 %, respectively, in the validating phase; FDG-PET, 50.0, 97.5, and 91.3 %, respectively, in the exploratory phase and 60.0, 100, and 94.1 %, respectively, in the validating phase; cytology, 68.4, 95.9, and 90.3 %, respectively, in the exploratory phase and 66.7, 100, and 85.7 %, respectively, in the validating phase.

Conclusions

Based on our results, CT and/or MRI appear to be inadequate methods for the evaluation of the response of lymph node(s) to CRT. In contrast, ultrasonography appears to be a highly sensitive and useful tool for positive screening at 6–8 weeks after CRT, and FDG-PET appears to be a highly specific and useful tool for negative screening at 8–12 weeks after CRT.
  相似文献   
165.
Although attention has focused on the chemopreventive action of retinoic acid (RA) in hepatocarcinogenesis, the functional role of RA in the liver has yet to be clarified. To explore the role of RA in the liver, we developed transgenic mice expressing RA receptor (RAR) alpha- dominant negative form in hepatocytes using albumin promoter and enhancer. At 4 months of age, the RAR alpha- dominant negative form transgenic mice developed microvesicular steatosis and spotty focal necrosis. Mitochondrial beta-oxidation activity of fatty acids and expression of its related enzymes, including VLCAD, LCAD, and HCD, were down-regulated; on the other hand, peroxisomal beta-oxidation and its related enzymes, including AOX and BFE, were up-regulated. Expression of cytochrome p4504a10, cytochrome p4504a12, and cytochrome p4504a14 was increased, suggesting that omega-oxidation of fatty acids in microsomes was accelerated. In addition, formation of H2O2 and 8-hydroxy-2'-deoxyguanosine was increased. After 12 months of age, these mice developed hepatocellular carcinoma and adenoma of the liver. The incidence of tumor formation increased with age. Expression of beta-catenin and cyclin D1 was enhanced and the TCF-4/beta-catenin complex was increased, whereas the RAR alpha/ beta-catenin complex was decreased. Feeding on a high-RA diet reversed histological and biochemical abnormalities and inhibited the occurrence of liver tumors. These results suggest that hepatic loss of RA function leads to the development of steatohepatitis and liver tumors. In conclusion, RA plays an important role in preventing hepatocarcinogenesis in association with fatty acid metabolism and Wnt signaling.  相似文献   
166.
167.
Hepatocellular carcinoma (HCC) ranks high among the most common and fatal cancers in the world. HCC develops from chronic liver diseases, especially from hepatitis C virus-related and hepatitis B virus (HBV)-related liver diseases. In this sense, useful biomarkers for HCC detection for the patients at risk of HCC are quite important. Recently, new therapies for HCC have been developed, and the prognosis of the patients has improved. However, considering the recurrence rate of HCC after treatment is very high, biomarkers that detect recurrence at an early stage are also required. In addition, since new drugs such as multikinase inhibitors have been introduced to the clinical scene, surrogate biomarkers to predict the effectiveness of treatment will be required in the near future. So far, many biomarkers for HCC have been developed, and their clinical usefulness has been assessed. As a result, several biomarkers for HCC are widely used. However, investigations to discover more useful biomarkers that fit in clinical settings are under way. In this review article, biomarkers for HCC are overviewed to examine their clinical usefulness.  相似文献   
168.
The "Guideline on the Use of New Anticancer Drugs for the Treatment of Hepatocellular Carcinoma" was prepared by the Study Group on New Liver Cancer Therapies established by the "Research Project on Emergency Measures to Overcome Hepatitis" under the auspices of the Health and Labour Sciences Research Grant. The Guideline brings together data collected by the Study Group on the use and incidence of adverse events in 264 patients with advanced hepatocellular carcinoma (HCC) treated using sorafenib and in 535 patients with advanced HCC treated using miriplatin at 16 participating institutions up until 22 December 2010, as well as referring to the published studies, academic presentations, and reports from the private sector. The aim of this Guideline is to facilitate understanding and current thinking regarding the proper usage of new anticancer drugs towards actual use in therapy. In terms of the format, the Guideline presents "clinical questions" on issues pertaining to medical care, makes "recommendations" on diagnosis and treatment in response to each of these clinical questions, and provides a rationale for these recommendations in the form of "scientific statements".  相似文献   
169.
Liver fibrosis is usually progressive, but it can occasionally be reversible if the causative agents are adequately removed or if patients are treated effectively. However, molecular mechanisms responsible for this reversibility of liver fibrosis have been poorly understood. To reveal the contribution of bone marrow (BM)-derived cells to the spontaneous regression of liver fibrosis, mice were treated with repeated carbon tetrachloride injections after hematopoietic reconstitution with enhanced green fluorescent protein (EGFP)-expressing BM cells. The distribution and characteristics of EGFP-positive (EGFP(+)) cells present in fibrotic liver tissue were examined at different time points after cessation of carbon tetrachloride intoxication. A large number of EGFP(+) cells were observed in liver tissue at peak fibrosis, which decreased during the recovery from liver fibrosis. Some of them, as well as EGFP-negative (EGFP(-)) liver resident cells, expressed matrix metalloproteinase (MMP)-13 and MMP-9. Whereas MMP-13 was transiently expressed mainly in the cells clustering in the periportal areas, MMP-9 expression and enzymatic activity were detected over the resolution process in several different kinds of cells located in the portal areas and along the fibrous septa. Therapeutic recruitment of BM cells by granulocyte colony-stimulating factor (G-CSF) treatment significantly enhanced migration of BM-derived cells into fibrotic liver and accelerated the regression of liver fibrosis. Experiments using transgenic mice overexpressing hepatocyte growth factor (HGF) indicated that G-CSF and HGF synergistically increased MMP-9 expression along the fibrous septa. CONCLUSION: Autologous BM cells contribute to the spontaneous regression of liver fibrosis, and their therapeutic derivation could be a new treatment strategy for intractable liver fibrosis.  相似文献   
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