WorldWideScience

Sample records for n-nitrosodiethylamine-induced liver tumorigenesis

  1. Diallyl sulfide protects against N-nitrosodiethylamine-induced liver tumorigenesis: Role of aldose reductase

    Institute of Scientific and Technical Information of China (English)

    Safinaz S Ibrahim; Noha N Nassar

    2008-01-01

    AIM: To evaluate the protective effect of diallyl sulfide (DAS) against N-nitrosodiethylamine (NDEA)-induced liver carcinogenesis. METHODS: Male Wistar rats received either NDEA or NDEA together with DAS as protection. Liver energy metabolism was assessed in terms of lactate, pyruvate, lactate/pyruvate, ATP levels, lactate dehydrogenase (LDH) and glucose-6-phosphate dehydrogenase (G6PD) activities. In addition, membrane disintegration of the liver cells was evaluated by measuring lipid-peroxidation products, measured as malondialdehyde (MDA); nitric oxide (NO) levels; glucose-6-phosphatase (G6Pase), catalase (CAT) and superoxide dismutase (SOD) activities. Uver DNA level, glutathione-S-transferase (GST) and cytochrome c oxidase activities were used as DNA fragmentation indices. Aldose reductase (AR) activity was measured as an index for cancer cells resistant to chemotherapy and histopathological examination was performed on liver sections from different groups. RESULTS: NDEA significantly disturbed liver functions and most of the aforementioned indices. Treatment with DAS significantly restored liver functions and hepatocellular integrity; improved parameters of energy metabolism and suppressed free-radical generation. CONCLUSION: We provide evidence that DAS exerts a protective role on liver functions and tissue integrity in face of enhanced tumorigenesis caused by NDEA, as well as improving cancer-cell sensitivity to chemotherapy. This is mediated through combating oxidative stress of free radicals, improving the energy metabolic state of the cell, and enhancing the activity of G6Pase, GST and AR enzymes.

  2. Non-invasive monitoring of carcinogenesis in N-nitrosodiethylamine induced liver cancer

    Energy Technology Data Exchange (ETDEWEB)

    Park, Ju Hui; Kang, Joo Hyun; Lee, Yong Jin; Lee, Tae Sup; Kim, Kwang Il; Cheon, Gi Jeong; Choi, Chang Woon; Lim, Sang Moo [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Park, Young Seo [Kyungwon University, Seongnam (Korea, Republic of)

    2010-10-15

    Molecular imaging based on reporter gene expression allows tissue-specific events or processes to be measured using the bioluminescence imaging (BLI) reporter gene expression vector controlled by specific enhancer/promoters. Alpha-fetoprotein (AFP), which is a tumor marker, is a serum glycoprotein that is expressed normally by fetal liver and yolk-sac cells, as well as in trace amounts in the fetal gastrointestinal tract. The serum concentration of AFP decreases rapidly after birth and its expression is repressed in adults. Approximately 80% of HCC patients show an increase in the AFP level. Therefore, AFP has been used for many years as a diagnostic and prognostic serum marker for HCC and transgenic system for AFP was proposed as a valuable tool for elucidation of mechanism of transcriptional regulation during liver development and hepatocarcinogenesis. In this study, firefly luciferase (fLuc) expressing transgenic mice controlled by the AFP enhancer/ promoter (enh/promoter) were produced to screen for the development of AFP-producing liver cancer. These models are expected to be useful for monitoring agents or drugs that modulate the AFP level as well as for measuring the specific signaling events important for liver cancer development

  3. Hepatoprotective activity of bacoside A against N-nitrosodiethylamine-induced liver toxicity in adult rats.

    Science.gov (United States)

    Janani, Panneerselvam; Sivakumari, Kanakarajan; Parthasarathy, Chandrakesan

    2009-10-01

    N-Nitrosodiethylamine (DEN) is a notorious carcinogen, present in many environmental factors. DEN induces oxidative stress and cellular injury due to enhanced generation of reactive oxygen species; free radical scavengers protect the membranes from DEN-induced damage. The present study was designed to evaluate the protective effect of bacoside A (the active principle isolated from Bacopa monniera Linn.) on carcinogen-induced damage in rat liver. Adult male albino rats were pretreated with 15 mg/kg body weight/day of bacoside A orally (for 14 days) and then intoxicated with single necrogenic dose of N-nitrosodiethylamine (200 mg/kg bodyweight, intraperitonially) and maintained for 7 days. The liver weight, lipid peroxidation (LPO), and activity of serum marker enzymes (aspartate transaminases, alanine transaminases, lactate dehydrogenase, alkaline phosphatase, and gamma-glutamyl transpeptidase) were markedly increased in carcinogen-administered rats, whereas the activities of marker enzymes were near normal in bacoside A-pretreated rats. Activities of antioxidant enzymes (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glutatione-S-transferase, and reduced glutathione) in liver also decreased in carcinogen-administered rats, which were significantly elevated in bacoside A-pretreated rats. It is concluded that pretreatment of bacoside A prevents the elevation of LPO and activity of serum marker enzymes and maintains the antioxidant system and thus protects the rats from DEN-induced hepatotoxicity.

  4. Carvacrol attenuates N-nitrosodiethylamine induced liver injury in experimental Wistar rats

    Directory of Open Access Journals (Sweden)

    Balan Rajan

    2015-06-01

    Full Text Available Carvacrol is a main constituent in the essential oils of countless aromatic plants including Origanum Vulgare and Thymus vulgari, which has been assessed for substantial pharmacological properties. In recent years, notable research has been embarked on to establish the biological actions of Carvacrol for its promising use in clinical applications. The present study is an attempt to reveal the protective role of Carvacrol against N-Nitrosodiethylamine (DEN induced hepatic injury in male Wistar albino rats. DEN is an egregious toxin, present in numerous environmental factors, which enhances chemical driven liver damage by inducing oxidative stress and cellular injury. Administration of DEN (200 mg/kg bodyweight, I.P to rats results in elevated marker enzymes (in both serum and tissue. Carvacrol (15 mg/kg body weight suppressed the elevation of marker enzymes (in both serum and tissue and augmented the antioxidants levels. The hoisted activities of Phase I enzymes and inferior activities of Phase II enzymes were observed in DEN-administered animals, whereas Carvacrol treated animals showed improved near normal activity. Histological observations also support the protective role of Carvacrol against DEN induced liver damage. Final outcome from our findings intimate that Carvacrol might be beneficial in attenuating toxin induced liver damage.

  5. A diet rich in cocoa attenuates N-nitrosodiethylamine-induced liver injury in rats.

    Science.gov (United States)

    Granado-Serrano, Ana Belén; Martín, María Angeles; Bravo, Laura; Goya, Luis; Ramos, Sonia

    2009-10-01

    The effects of cocoa feeding against N-nitrosodiethylamine (DEN)-induced liver injury were studied in rats. Animals were divided into five groups. Groups 1 and 2 were fed with standard and cocoa-diet, respectively. Groups 3 and 4 were injected with DEN at 2 and 4 weeks, and fed with standard and cocoa-diet, respectively. Group 5 was treated with DEN, received the standard diet for 4 weeks and then it was replaced by the cocoa-diet. DEN-induced hepatic damage caused a significant increase in damage markers, as well as a decrease in the hepatic glutathione, diminished levels of p-ERK and enhanced protein carbonyl content, caspase-3 activity and values of p-AKT and p-JNK. The cocoa-rich diet prevented the reduction of hepatic glutathione concentration and catalase and GPx activities in DEN-injected rats, as well as diminished protein carbonyl content, caspase-3 activity, p-AKT and p-JNK levels, and increased GST activity. However, cocoa administration did not abrogate the DEN-induced body weight loss and the increased levels of hepatic-specific enzymes and LDH. These results suggested that cocoa-rich diet attenuates the DEN-induced liver injury.

  6. Dynamic contrast enhanced MR imaging for evaluation of angiogenesis of hepatocellular nodules in liver cirrhosis in N-nitrosodiethylamine induced rat model

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Wei; Chen, Hui Juan; Huang, Wei; Zhang, Long Jiang [Medical School of Nanjing University, Department of Medical Imaging, Jinling Hospital, Nanjing, Jiangsu (China); Wang, Zhen J. [University of California, Department of Radiology and Biomedical Imaging, San Francisco, CA (United States)

    2017-05-15

    To investigate whether dynamic contrast -enhanced MRI (DCE-MRI) can distinguish the type of liver nodules in a rat model with N-nitrosodiethylamine- induced cirrhosis. Liver nodules in cirrhosis were induced in 60 male Wistar rats via 0.01 % N-nitrosodiethylamine in the drinking water for 35-100 days. The nodules were divided into three groups: regenerative nodule (RN), dysplastic nodule (DN), and hepatocellular carcinoma (HCC). DCE-MRI was performed, and parameters including transfer constant (K{sup trans}), rate constant (K{sub ep}), extravascular extracellular space volume fraction (V{sub e}), and initial area under the contrast concentration versus time curve (iAUC) were measured and compared. The highest K{sup trans} and iAUC values were seen in HCC, followed by DN and RN (all P < 0.05). The area under the receiver operating characteristic curve (AUROC) for DN and HCC were 0.738 and 0.728 for K{sup trans} and iAUC, respectively. The AUROC for HCC were 0.850 and 0.840 for K{sup trans} and iAUC, respectively. Ordinal logistic regression analysis showed that K{sup trans} had a high goodness of fit (0.970, 95 % confidence interval, 13.751-24.958). DCE-MRI is a promising method to differentiate of liver nodules. Elevated K{sup trans} suggested that the nodules may be transformed into HCC. (orig.)

  7. Chemoprevention and cytotoxic effect of Bauhinia variegata against N-nitrosodiethylamine induced liver tumors and human cancer cell lines.

    Science.gov (United States)

    Rajkapoor, B; Jayakar, B; Murugesh, N; Sakthisekaran, D

    2006-04-06

    The chemopreventive and cytotoxic effect of ethanol extract of Bauhinia variegata (EBV) was evaluated in N-nitrosodiethylamine (DEN, 200 mg/kg) induced experimental liver tumor in rats and human cancer cell lines. Oral administration of ethanol extract of Bauhinia variegata (250 mg/kg) effectively suppressed liver tumor induced by DEN as revealed by decrease in DEN induced elevated levels of serum glutamate pyruvate transaminase (SGPT), serum glutamate oxaloacetate transaminase (SGOT), alkaline phosphatase (ALP), total bilirubin, gamma glutamate transpeptidase (GGTP), lipid peroxidase (LPO), glutathione peroxidase (GPx) and glutathione S-transferase (GST). The extract produced an increase in enzymatic antioxidant (superoxide dismutase and catalase) levels and total proteins when compared to those in liver tumor bearing rats. The histopathological changes of liver samples were compared with respective controls. EBV was found to be cytotoxic against human epithelial larynx cancer (HEp2) and human breast cancer (HBL-100) cells. These results show a significant chemopreventive and cytotoxic effect of ethanol extract of Bauhinia variegata against DEN induced liver tumor and human cancer cell lines.

  8. Protective Effect of Prosopis cineraria Against N-Nitrosodiethylamine Induced Liver Tumor by Modulating Membrane Bound Enzymes and Glycoproteins

    Directory of Open Access Journals (Sweden)

    Naina Mohamed Pakkir Maideen

    2012-06-01

    Full Text Available Purpose: The objective of the present study was to evaluate the protective effect of methanol extract of Prosopis cineraria (MPC against N-nitrosodiethylamine (DEN, 200mg/kg induced Phenobarbital promoted experimental liver tumors in male Wistar rats. Methods: The rats were divided into four groups, each group consisting of six animals. Group 1 served as control animals. Liver tumor was induced in group 2, 3, and 4 and Group 3 animals received MPC 200mg/kg and Group 4 animals received MPC 400mg/kg. Results: Administration of DEN has brought down the levels of membrane bound enzymes like Na+/ K+ ATPase, Mg2+ ATPase and Ca2+ATPase which were later found to be increased by the administration of Prosopis cineraria (200 and 400mg/kg in dose dependent manner. The MPC extract also suppressed the levels of glycoproteins like Hexose, Hexosamine and Sialic acid when compared to liver tumor bearing animals. Conclusions: Our study suggests that MPC may extend its protective role by modulating the levels of membrane bound enzymes and suppressing glycoprotein levels.

  9. Role of Prosopis cineraria against N-nitrosodiethylamine-induced liver tumor in rats with reference to marker enzymes and nucleic acid contents

    Directory of Open Access Journals (Sweden)

    Naina mohamed Pakkir Maideen

    2011-06-01

    Full Text Available The effect of methanol extract of Prosopis cineraria against experimental liver tumor in rats was studied. Liver tumor was induced by the administration of N-nitrosodiethylamine (200 mg/kg and it was promoted by phenobarbital administration. Methanol extract (200 and 400 mg/kg was administered to determine the protective activity. Administration of methanol extract suppressed the liver tumor effectively as revealed by the decrease in elevated levels of aryl hydrocarbon hydroxylase, lactate dehydrogenase, g-glutamyl transpeptidase (g-GTP, 5’nucleotidase, deoxyribonucleic acid (DNA and ribonucleic acid (RNA. We found that methanol extract may extend its protective role by modifying the levels of marker enzymes and nucleic acid contents.

  10. N-亚硝基二乙胺(DEN)诱导SD大鼠肝癌模型的研究%Research of N-nitrosodiethylamine induced SD rat model of liver cancer

    Institute of Scientific and Technical Information of China (English)

    柴红涛; 唐恩奇; 李滨; 蒋欢欢; 张剑波; 刘艳华; 汪丽燕

    2016-01-01

    Objective To set up an animal model similar to the process of human liver cancer so as to study the tumorigenesis of liv-er cancer. Methods Sixty-five male SD rats with the weight of 120~150 g were randomly divided into the experimental group(50 rats)and the control group(15 rats) after acclimating for one week. Rats of the experiment group were given DEN(76 ppm) in drinking water for 6 weeks,followed by free drinking water for 3 weeks,and then continued drinking water containing DEN(76 ppm)to 20 weeks. The rats of con-trol group were given free drinking water conventionally. Results Pathological examination confirmed that DEN could induce the formation of liver cancer in rats. After 14 weeks the rate of cancer was about 66. 7%(10/15). Rat liver carcinogenesis could be divided into the three stages of hepatitis,cirrhosis and liver cancer. Conclusion Feeding with DEN(76ppm)can induce liver cancer model in rats,which can pro-vide reliable animal model for the study of the carcinogenesis of rat liver cancer.%目的 建立与人类的肝癌发生发展过程相似的动物模型,以便研究肝癌的发生发展过程.方法 取体质量120~150 g雄性SD大鼠65只,适应环境1周后随机分为实验组(50只)和对照组(15只),实验组饮用含N-亚硝基二乙(DEN)(浓度为76 ppm)(以下简称DEN)的水连续6周后停药,改自由饮水3周,再继续饮用含DEN(76 ppm)的水至20周.对照组常规自由饮水.结果 病理学检查证实DEN可诱发大鼠形成肝癌,14周后成癌率为66.7%(10/15),大鼠肝癌的癌变过程大致可分为肝炎期、肝硬化期和肝癌期三个发展阶段.结论 饲以76 ppm剂量DEN可诱发大鼠肝癌模型的建立,可以为我们研究大鼠肝癌的发生发展过程提供可靠的动物模型.

  11. Exacerbation of N-nitrosodiethylamine Induced Hepatotoxicity and DNA Damage in Mice Exposed to Chronic Unpredictable Stress

    Directory of Open Access Journals (Sweden)

    Nayeem Bilal

    2017-06-01

    Full Text Available Psychological stress contributes to increased susceptibility to a number of diseases including cancer. The present study was designed to assess the effect of chronic unpredictable stress on N-nitrosodiethylamine induced liver toxicity in terms of in vivo antioxidant status and DNA damage in Swiss albino mice. The animals used in this study were randomized into different groups based on the treatment with N-nitrosodiethylamine or chronic unpredictable stress alone and post-stress administration of N-nitrosodiethylamine. The mice were sacrificed after 12 weeks of treatment, and the status of major enzymatic and non-enzymatic antioxidants, liver function markers, lipid peroxidation and the extent of DNA damage were determined in circulation and liver tissues of all the groups. The N-nitrosodiethylamine treated group showed significantly compromised levels of the antioxidant enzymes, lipid peroxidation, and the liver function markers with enhanced DNA damage as compared to chronic unpredictable stress or control groups. A similar but less typical pattern observed in the chronic unpredictable stress treated mice. All the measured biochemical parameters were significantly altered in the group treated with the combination of chronic unpredictable stress and N-nitrosodiethylamine when compared to controls, or chronic unpredictable stress alone and/or N-nitrosodiethylamine alone treated groups. Thus, exposure to continuous, unpredictable stress conditions even in general life may significantly enhance the hepatotoxic potential of N-nitrosodiethylamine through an increase in the oxidative stress and DNA damage.

  12. Exacerbation of N-nitrosodiethylamine Induced Hepatotoxicity and DNA Damage in Mice Exposed to Chronic Unpredictable Stress.

    Science.gov (United States)

    Bilal, Nayeem; Suhail, Nida; Hasan, Shirin; Ashraf, Ghulam M; Fatima, Sabiha; Khan, Husain Y; Alharbi, Mariam S; Alexiou, Athanasios; Banu, Naheed

    2017-01-01

    Psychological stress contributes to increased susceptibility to a number of diseases including cancer. The present study was designed to assess the effect of chronic unpredictable stress on N-nitrosodiethylamine induced liver toxicity in terms of in vivo antioxidant status and DNA damage in Swiss albino mice. The animals used in this study were randomized into different groups based on the treatment with N-nitrosodiethylamine or chronic unpredictable stress alone and post-stress administration of N-nitrosodiethylamine. The mice were sacrificed after 12 weeks of treatment, and the status of major enzymatic and non-enzymatic antioxidants, liver function markers, lipid peroxidation and the extent of DNA damage were determined in circulation and liver tissues of all the groups. The N-nitrosodiethylamine treated group showed significantly compromised levels of the antioxidant enzymes, lipid peroxidation, and the liver function markers with enhanced DNA damage as compared to chronic unpredictable stress or control groups. A similar but less typical pattern observed in the chronic unpredictable stress treated mice. All the measured biochemical parameters were significantly altered in the group treated with the combination of chronic unpredictable stress and N-nitrosodiethylamine when compared to controls, or chronic unpredictable stress alone and/or N-nitrosodiethylamine alone treated groups. Thus, exposure to continuous, unpredictable stress conditions even in general life may significantly enhance the hepatotoxic potential of N-nitrosodiethylamine through an increase in the oxidative stress and DNA damage.

  13. Dose-response effects of Elephantopus scaber methanolic extract on N-nitrosodiethylamine-induced hepatotoxicity in rats

    Institute of Scientific and Technical Information of China (English)

    A.Linza; P.J.Wills; P.N.Ansil; S.P.Prabha; A.Nitha; B.Latha; K.O.Sheeba; M.S.Latha

    2013-01-01

    AIM:A decoction of Elephantopus scaber (Asteraceae) root is used to treat liver disorders in Indian and Chinese traditional medicine.The study was designed to examine the dose response effects of E.scaber methanolic extract on rats exposed to N-nitrosodiethylamine (NDEA) induced hepatotoxicity (0.02% NDEA in water five days per week,per oral) in preventive and curative models.METHODS:In preventive groups,NDEA was administered for six weeks.Daily doses of E.scaber methanolic extract (200 and 100mg·kg-1) started one week before the onset of NDEA intoxication and continued for six weeks.In curative animals,NDEA was administered for six weeks followed by treatment with the methanolic n-hexane extract of E.scaber (200 and 100mg·kg-1) for ten days.RESULTS:E.scaber extract treatment significantly (P≤0.05) reduced the levels of AST,ALT,and MDA in both experimental groups.The extract also enhanced the antioxidant enzyme and protein levels in rats intoxicated with NDEA.Treatment with the extract dose dependently protected the liver from NDEA-induced hepatotoxicity with normal hepatocytes and uniform sinusoids,but in some areas showed degenerating hepatic cells in both treatment groups.CONCLUSION:E.scaber methanolic extract dose dependently prevented and reversed the hepatotoxicity induced by NDEA in both experimental models.

  14. Antioxidant effect of lycopene-enriched tomato paste on N-nitrosodiethylamine-induced oxidative stress in rats.

    Science.gov (United States)

    Kujawska, Malgorzata; Ewertowska, Malgorzata; Adamska, Teresa; Sadowski, Czeslaw; Ignatowicz, Ewa; Jodynis-Liebert, Jadwiga

    2014-12-01

    Lycopene is a carotenoid pigment produced by vegetables and fruits, with tomatoes and their processed products being the most abundant sources. A high number of conjugated dienes make lycopene a powerful radical scavenger. Its antioxidant properties are considered to be primarily involved in many beneficial health effects. The present study was designed to assess the protective effect of lycopene-enriched tomato paste against N-nitrosodiethylamine (NDEA)-induced oxidative stress in rats. Forty-eight male Wistar rats were divided randomly into six groups. Four groups were treated with tomato paste, per os, for 28 days in doses which were equivalent to 0.5 (groups II and V) and 2.5 mg/kg b.w./day of lycopene (groups III and VI). Rats from groups IV-VI were given intraperitoneally a single dose of NDEA, 150 mg/kg b.w. Group I (control) was given distilled water. Pretreatment with tomato paste protected the antioxidant enzymes: superoxide dismutase, catalase and glutathione reductase. Their activity was recovered by 32-97 %, as compared to NDEA-treated rats. Microsomal lipid peroxidation in the liver was decreased in rats pretreated with a lower dose of tomato paste by 28 %, as compared to animals given NDEA alone. Pretreatment with tomato paste caused a decrease in plasma concentration of protein carbonyls, even below the control level, in rats given NDEA. Moreover, a 10 % reduction of DNA damage in leucocytes caused by NDEA was observed. The tomato paste tested was able to suppress NDEA-induced oxidative stress in rats.

  15. Aerosolized 3-bromopyruvate inhibits lung tumorigenesis without causing liver toxicity.

    Science.gov (United States)

    Zhang, Qi; Pan, Jing; North, Paula E; Yang, Shoua; Lubet, Ronald A; Wang, Yian; You, Ming

    2012-05-01

    3-Bromopyruvate, an alkylating agent and a well-known inhibitor of energy metabolism, has been proposed as a specific anticancer agent. However, the chemopreventive effect of 3-bromopyruvate in lung tumorigenesis has not been tested. In this study, we investigated the chemopreventive activity of 3-bromopyruvate in a mouse lung tumor model. Benzo(a)pyrene was used to induce lung tumors, and 3-bromopyruvate was administered by oral gavage to female A/J mice. We found that 3-bromopyruvate significantly decreased tumor multiplicity and tumor load by 58% and 83%, respectively, at a dose of 20 mg/kg body weight by gavage. Due to the known liver toxicity of 3-bromopyruvate in animal models given large doses of 3-bromopyruvate, confirmed in this study, we decided to test the chemopreventive activity of aerosolized 3-bromopyruvate in the same lung tumor model. As expected, aerosolized 3-bromopyruvate similarly significantly decreased tumor multiplicity and tumor load by 49% and 80%, respectively, at a dose of 10 mg/mL by inhalation. Interestingly, the efficacy of aerosolized 3-bromopyruvate did not accompany any liver toxicity indicating that it is a safer route of administering this compound. Treatment with 3-bromopyruvate increased immunohistochemical staining for cleaved caspase-3, suggesting that the lung tumor inhibitory effects of 3-bromopyruvate were through induction of apoptosis. 3-Bromopyruvate also dissociated hexokinase II from mitochondria, reduced hexokinase activity, and blocked energy metabolism in cancer cells, finally triggered cancer cell death and induced apoptosis through caspase-3, and PARP in human lung cancer cell line. The ability of 3-bromopyruvate to inhibit mouse lung tumorigenesis, in part through induction of apoptosis, merits further investigation of this compound as a chemopreventive agent for human lung cancer.

  16. AMELIORATIVE EFFECT OF HYGROPHILA AURICULATA (K. SCHUM HEINE ON LIPID PEROXIDATION IN A RAT MODEL OF N-NITROSODIETHYLAMINE INDUCED HEPATOCELLULAR CARCINOMA

    Directory of Open Access Journals (Sweden)

    S. Premkumari et al

    2012-09-01

    Full Text Available This study was designed to investigate the ameliorative effect effect of Hygrophila auriculata (H. auriculata on lipid peroxidation (LPO in Nnitrosodiethylamine induced Hepatocellular Carcinoma (HCC in rats. Experimental rats were divided into different groups: normal, NNitrosodiethylamine induced hepatocellular Carcinoma bearing rats, H.auriculata treated hepatocellular carcinoma bearing rats, (200 mg/kg body weight, doses for 28 days, Animals treated with plant extract alone for 28 days. After the treatment period of 28th day , effect of H.auriculata on LPO in serum , liver and kidney of control and experimental animals were assayed and compared. Under basal and in the presence of inducers (H2O2, the levels of LPO were increased significantly (p<0.001 in group II cancer bearing animals where as the levels of LPO in the presence of ascorbic acid and FeSO4, were not statistically different. In group III plant extract treated animals, significant decrease on LPO was observed. However, the changes in the above parameters were comparable with control.Thus, methanolic extract of H. auriculata ameliorated the LPO which is associated with the development of HCC to near normal in HCC bearing rats which could be attributed to the presence of polyphenols and flavonoids in the plant extract. Antioxidants act as radical scavenger, inhibit LPO and other free radicalmediated processes, thereby protecting the human body from various diseases.

  17. Protective Effects of Total Glucosides of Paeony on N-nitrosodiethylamine-induced Hepatocellular Carcinoma in Rats via Down-regulation of Regulatory B Cells.

    Science.gov (United States)

    Song, S S; Yuan, P F; Li, P P; Wu, H X; Ni, W J; Lu, J T; Wei, W

    2015-01-01

    Total glucoside of paeony (TGP), extracted from the root of Paeonia Lactiflora, has been known to show anti-inflammatory, anti-oxidative, hepato-protective and immuno-regulatory activities. The aim of this present study was to determine the anti-tumor effect of TGP against N-nitrosodiethylamine (DEN)-induced hepatocellular carcinoma (HCC) in rats, and to find the related mechanisms. Rat HCC model was established by intragastrically administrating with DEN (8 mg/kg). We found the number of tumor nodules and the index of liver and spleen were increased in the model group compared with the normal group, and was significantly decreased by TGP. Additionally, TGP obviously improved the hepatic pathological lesions induced by DEN, and decreased the elevated levels of serum alanine aminotransferase (ALT), glutamic oxalacetic transaminase (AST), alkaline phosphatase (ALP) and alpha fetoprotein (AFP) by DEN. Moreover, TGP decreased the level of B cell-activating factor (BAFF) and the proportion of IL-10-producing regulatory B cells (Bregs), and the decrease of BAFF by TGP is positively correlated to the decrease of IL-10-producing Bregs by TGP. These results suggest that TGP had a good therapeutic action on DEN-induced HCC rats, which might be due to its down-regulation of Bregs through reducing the level of BAFF.

  18. An inducible krasV12 transgenic zebrafish model for liver tumorigenesis and chemical drug screening

    Directory of Open Access Journals (Sweden)

    Anh Tuan Nguyen

    2012-01-01

    Because Ras signaling is frequently activated by major hepatocellular carcinoma etiological factors, a transgenic zebrafish constitutively expressing the krasV12 oncogene in the liver was previously generated by our laboratory. Although this model depicted and uncovered the conservation between zebrafish and human liver tumorigenesis, the low tumor incidence and early mortality limit its use for further studies of tumor progression and inhibition. Here, we employed a mifepristone-inducible transgenic system to achieve inducible krasV12 expression in the liver. The system consisted of two transgenic lines: the liver-driver line had a liver-specific fabp10 promoter to produce the LexPR chimeric transactivator, and the Ras-effector line contained a LexA-binding site to control EGFP-krasV12 expression. In double-transgenic zebrafish (driver-effector embryos and adults, we demonstrated mifepristone-inducible EGFP-krasV12 expression in the liver. Robust and homogeneous liver tumors developed in 100% of double-transgenic fish after 1 month of induction and the tumors progressed from hyperplasia by 1 week post-treatment (wpt to carcinoma by 4 wpt. Strikingly, liver tumorigenesis was found to be ‘addicted’ to Ras signaling for tumor maintenance, because mifepristone withdrawal led to tumor regression via cell death in transgenic fish. We further demonstrated the potential use of the transparent EGFP-krasV12 larvae in inhibitor treatments to suppress Ras-driven liver tumorigenesis by targeting its downstream effectors, including the Raf-MEK-ERK and PI3K-AKT-mTOR pathways. Collectively, this mifepristone-inducible and reversible krasV12 transgenic system offers a novel model for understanding hepatocarcinogenesis and a high-throughput screening platform for anti-cancer drugs.

  19. Role of PINCH and its partner tumor suppressor Rsu-1 in regulating liver size and tumorigenesis.

    Directory of Open Access Journals (Sweden)

    Shashikiran Donthamsetty

    Full Text Available Particularly interesting new cysteine-histidine-rich protein (PINCH protein is part of the ternary complex known as the IPP (integrin linked kinase (ILK-PINCH-Parvin-α complex. PINCH itself binds to ILK and to another protein known as Rsu-1 (Ras suppressor 1. We generated PINCH 1 and PINCH 2 Double knockout mice (referred as PINCH DKO mice. PINCH2 elimination was systemic whereas PINCH1 elimination was targeted to hepatocytes. The genetically modified mice were born normal. The mice were sacrificed at different ages after birth. Soon after birth, they developed abnormal hepatic histology characterized by disorderly hepatic plates, increased proliferation of hepatocytes and biliary cells and increased deposition of extracellular matrix. After a sustained and prolonged proliferation of all epithelial components, proliferation subsided and final liver weight by the end of 30 weeks in livers with PINCH DKO deficient hepatocytes was 40% larger than the control mice. The livers of the PINCH DKO mice were also very stiff due to increased ECM deposition throughout the liver, with no observed nodularity. Mice developed liver cancer by one year. These mice regenerated normally when subjected to 70% partial hepatectomy and did not show any termination defect. Ras suppressor 1 (Rsu-1 protein, the binding partner of PINCH is frequently deleted in human liver cancers. Rsu-1 expression is dramatically decreased in PINCH DKO mouse livers. Increased expression of Rsu-1 suppressed cell proliferation and migration in HCC cell lines. These changes were brought about not by affecting activation of Ras (as its name suggests but by suppression of Ras downstream signaling via RhoGTPase proteins. In conclusion, our studies suggest that removal of PINCH results in enlargement of liver and tumorigenesis. Decreased levels of Rsu-1, a partner for PINCH and a protein often deleted in human liver cancer, may play an important role in the development of the observed phenotype.

  20. Metformin suppresses diethylnitrosamine-induced liver tumorigenesis in obese and diabetic C57BL/KsJ-+Leprdb/+Leprdb mice.

    Directory of Open Access Journals (Sweden)

    Tomohiko Ohno

    Full Text Available Obesity and related metabolic disorders, such as diabetes mellitus, raise the risk of liver carcinogenesis. Metformin, which is widely used in the treatment of diabetes, ameliorates insulin sensitivity. Metformin is also thought to have antineoplastic activities and to reduce cancer risk. The present study examined the preventive effect of metformin on the development of diethylnitrosamine (DEN-induced liver tumorigenesis in C57BL/KsJ-+Leprdb/+Leprdb (db/db obese and diabetic mice. The mice were given a single injection of DEN at 2 weeks of age and subsequently received drinking water containing metformin for 20 weeks. Metformin administration significantly reduced the multiplicity of hepatic premalignant lesions and inhibited liver cell neoplasms. Metformin also markedly decreased serum levels of insulin and reduced insulin resistance, and inhibited phosphorylation of Akt, mammalian target of rapamycin (mTOR, and p70S6 in the liver. Furthermore, serum levels of leptin were decreased, while those of adiponectin were increased by metformin. These findings suggest that metformin prevents liver tumorigenesis by ameliorating insulin sensitivity, inhibiting the activation of Akt/mTOR/p70S6 signaling, and improving adipokine imbalance. Therefore, metformin may be a potent candidate for chemoprevention of liver tumorigenesis in patients with obesity or diabetes.

  1. Yes-associated protein in the liver: Regulation of hepatic development, repair, cell fate determination and tumorigenesis.

    Science.gov (United States)

    Nguyen, Quy; Anders, Robert A; Alpini, Gianfranco; Bai, Haibo

    2015-10-01

    The liver is a vital organ that plays a major role in many bodily functions from protein production and blood clotting to cholesterol, glucose and iron metabolism and nutrition storage. Maintenance of liver homeostasis is critical for these essential bodily functions and disruption of liver homeostasis causes various kinds of liver diseases, some of which have high mortality rate. Recent research advances of the Hippo signalling pathway have revealed its nuclear effector, Yes-associated protein, as an important regulator of liver development, repair, cell fate determination and tumorigenesis. Therefore, a precise control of Yes-associated protein activity is critical for the maintenance of liver homeostasis. This review is going to summarize the discoveries on how the manipulation of Yes-associated protein activity affects liver homeostasis and induces liver diseases and the regulatory mechanisms that determine the Yes-associated protein activity in the liver. Finally, we will discuss the potential of targeting Yes-associated protein as therapeutic strategies in liver diseases.

  2. Dietary administration of Nexrutine inhibits rat liver tumorigenesis and induces apoptotic cell death in human hepatocellular carcinoma cells

    Directory of Open Access Journals (Sweden)

    Shamshad Alam

    2015-01-01

    Full Text Available Epidemiological studies suggested that plant-based dietary supplements can reduce the risk of liver cancer. Nexrutine (NX, an herbal extract from Phellodendronamurense, has been shown to have anti-inflammatory, anti-microbial and anti-tumor activities. In the present study, we have shown the anti-tumor potential of NX against Solt-Farber model with elimination of PH, rat liver tumor induced by diethylnitrosoamine (DEN as carcinogen and 2-acetylaminofluorene (2-AAF as co-carcinogen. The elucidation of mechanistic pathways was explored in human liver cancer cells. Dietary intake of NX significantly decreased the cell proliferation and inflammation, as well as increased apoptosis in the liver sections of DEN/2-AAF-treated rats. Moreover, NX (2.5–10 μg/ml exposure significantly decreased the viability of liver cancer cells and modulated the levels of Bax and Bcl-2 proteins levels. NX treatment resulted in increased cytochrome-c release and cleavage of caspases 3 and 9. In addition, NX decreased the expression of CDK2, CDK4 and associated cyclins E1 and D1, while up-regulated the expression of p21, p27 and p53 expression. NX also enhanced phosphorylation of the mitogen-activated protein kinases (MAPKs ERK1/2, p38 and JNK1/2. Collectively, these findings suggested that NX-mediated protection against DEN/2-AAF-induced liver tumorigenesis involves decrease in cell proliferation and enhancement in apoptotic cell death of liver cancer cells.

  3. Unravelling the connection between metabolism and tumorigenesis through studies of the liver kinase B1 tumour suppressor

    Directory of Open Access Journals (Sweden)

    David B Shackelford

    2013-01-01

    Full Text Available The liver kinase B1 (LKB1 tumour suppressor functions as a master regulator of growth, metabolism and survival in cells, which is frequently mutated in sporadic human non-small cell lung and cervical cancers. LKB1 functions as a key upstream activator of the AMP-activated protein kinase (AMPK, a central metabolic switch found in all eukaryotes that govern glucose and lipid metabolism and autophagy in response to alterations in nutrients and intracellular energy levels. The LKB1/AMPK signalling pathway suppresses mammalian target of rapamycin complex 1 (mTORC1, an essential regulator of cell growth in all eukaryotes that is deregulated in a majority of human cancers. LKB1 inactivation in cancer leads to both tumorigenesis and metabolic deregulation through the AMPK and mTORC1-signalling axis and there remain critical challenges to elucidate the direct role LKB1 inactivation plays in driving aberrant metabolism and tumour growth. This review addresses past and current efforts to delineate the molecular mechanisms fueling metabolic deregulation and tumorigenesis following LKB1 inactivation as well as translational promise of therapeutic strategies aimed at targeting LKB1-deficient tumors.

  4. Continuous cell injury promotes hepatic tumorigenesis in cdc42-deficient mouse liver

    DEFF Research Database (Denmark)

    van Hengel, Jolanda; D'Hooge, Petra; Hooghe, Bart

    2008-01-01

    BACKGROUND & AIMS: The Rho small guanosine triphosphatase Cdc42 is critical for diverse cellular functions, including regulation of actin organization, cell polarity, intracellular membrane trafficking, transcription, cell-cycle progression, and cell transformation. This implies that Cdc42 might ....... CONCLUSIONS: We describe a mouse model in which chronic liver disease leads to hepatocarcinogenesis....

  5. Toxaphene-induced mouse liver tumorigenesis is mediated by the constitutive androstane receptor.

    Science.gov (United States)

    Wang, Zemin; Li, Xilin; Wu, Qiangen; Lamb, James C; Klaunig, James E

    2017-02-20

    Toxaphene was shown to increase liver tumor incidence in B6C3F1 mice following chronic dietary exposure. Preliminary evidence supported a role for the constitutive androstane receptor (CAR) in the mode of action of toxaphene-induced mouse liver tumors. However, these results could not rule out a role for the pregnane X receptor (PXR) in liver tumor formation. To define further the nuclear receptors involved in this study, we utilized CAR, PXR and PXR/CAR knockout mice (CAR(-/-) , PXR(-/-) and PXR(-/-) /CAR(-/-) ) along with the wild-type C57BL/6. In this study CAR-responsive genes Cyp3a11 and Cyp2b10 were induced in the liver of C57BL/6 (wild-type) mice by toxaphene (30-570-fold) (at the carcinogenic dose 320 ppm) and phenobarbital (positive control) (16-420-fold) following 14 days' dietary treatment. In contrast, in CAR(-/-) mice, no induction of these genes was seen following treatment with either chemical. Cyp3a11 and Cyp2b10 were also induced in PXR(-/-) mice with toxaphene and phenobarbital but were not changed in treated PXR(-/-) /CAR(-/-) mice. Similarly, induction of liver pentoxyresorufin-O-deethylase (CAR activation) activity by toxaphene and phenobarbital was absent in CAR(-/-) and PXR(-/-) /CAR(-/-) mice treated with phenobarbital or toxaphene. Ethoxyresorufin-O-deethylase (EROD, represents aryl hydrocarbon receptor activation) activity in CAR(-/-) mice treated with toxaphene or phenobarbital was increased compared with untreated control, but lower overall in activity in comparison to the wild-type mouse. Liver EROD activity was also induced by both phenobarbital and toxaphene in the PXR(-/-) mice but not in the PXR(-/-) /CAR(-/-) mice. Toxaphene treatment increased 7-benzyloxyquinoline activity (a marker for PXR activation) in a similar pattern to that seen with pentoxyresorufin-O-deethylase. These observations indicate that EROD and PXR activation are evidence, as expected, of secondary overlap to primary CAR receptor activation. Together, these

  6. Identification of Chemical Inhibitors of β-Catenin-Driven Liver Tumorigenesis in Zebrafish.

    Directory of Open Access Journals (Sweden)

    Kimberley J Evason

    2015-07-01

    Full Text Available Hepatocellular carcinoma (HCC is one of the most lethal human cancers. The search for targeted treatments has been hampered by the lack of relevant animal models for the genetically diverse subsets of HCC, including the 20-40% of HCCs that are defined by activating mutations in the gene encoding β-catenin. To address this chemotherapeutic challenge, we created and characterized transgenic zebrafish expressing hepatocyte-specific activated β-catenin. By 2 months post fertilization (mpf, 33% of transgenic zebrafish developed HCC in their livers, and 78% and 80% of transgenic zebrafish showed HCC at 6 and 12 mpf, respectively. As expected for a malignant process, transgenic zebrafish showed significantly decreased mean adult survival compared to non-transgenic control siblings. Using this novel transgenic model, we screened for druggable pathways that mediate β-catenin-induced liver growth and identified two c-Jun N-terminal kinase (JNK inhibitors and two antidepressants (one tricyclic antidepressant, amitriptyline, and one selective serotonin reuptake inhibitor that suppressed this phenotype. We further found that activated β-catenin was associated with JNK pathway hyperactivation in zebrafish and in human HCC. In zebrafish larvae, JNK inhibition decreased liver size specifically in the presence of activated β-catenin. The β-catenin-specific growth-inhibitory effect of targeting JNK was conserved in human liver cancer cells. Our other class of hits, antidepressants, has been used in patient treatment for decades, raising the exciting possibility that these drugs could potentially be repurposed for cancer treatment. In support of this proposal, we found that amitriptyline decreased tumor burden in a mouse HCC model. Our studies implicate JNK inhibitors and antidepressants as potential therapeutics for β-catenin-induced liver tumors.

  7. Dietary and genetic obesity promote liver inflammation and tumorigenesis by enhancing IL-6 and TNF expression.

    Science.gov (United States)

    Park, Eek Joong; Lee, Jun Hee; Yu, Guann-Yi; He, Guobin; Ali, Syed Raza; Holzer, Ryan G; Osterreicher, Christoph H; Takahashi, Hiroyuki; Karin, Michael

    2010-01-22

    Epidemiological studies indicate that overweight and obesity are associated with increased cancer risk. To study how obesity augments cancer risk and development, we focused on hepatocellular carcinoma (HCC), the common form of liver cancer whose occurrence and progression are the most strongly affected by obesity among all cancers. We now demonstrate that either dietary or genetic obesity is a potent bona fide liver tumor promoter in mice. Obesity-promoted HCC development was dependent on enhanced production of the tumor-promoting cytokines IL-6 and TNF, which cause hepatic inflammation and activation of the oncogenic transcription factor STAT3. The chronic inflammatory response caused by obesity and enhanced production of IL-6 and TNF may also increase the risk of other cancers. Copyright 2010 Elsevier Inc. All rights reserved.

  8. Hippo signaling interactions with Wnt/β-catenin and Notch signaling repress liver tumorigenesis.

    Science.gov (United States)

    Kim, Wantae; Khan, Sanjoy Kumar; Gvozdenovic-Jeremic, Jelena; Kim, Youngeun; Dahlman, Jason; Kim, Hanjun; Park, Ogyi; Ishitani, Tohru; Jho, Eek-Hoon; Gao, Bin; Yang, Yingzi

    2017-01-03

    Malignant tumors develop through multiple steps of initiation and progression, and tumor initiation is of singular importance in tumor prevention, diagnosis, and treatment. However, the molecular mechanism whereby a signaling network of interacting pathways restrains proliferation in normal cells and prevents tumor initiation is still poorly understood. Here, we have reported that the Hippo, Wnt/β-catenin, and Notch pathways form an interacting network to maintain liver size and suppress hepatocellular carcinoma (HCC). Ablation of the mammalian Hippo kinases Mst1 and Mst2 in liver led to rapid HCC formation and activated Yes-associated protein/WW domain containing transcription regulator 1 (YAP/TAZ), STAT3, Wnt/β-catenin, and Notch signaling. Previous work has shown that abnormal activation of these downstream pathways can lead to HCC. Rigorous genetic experiments revealed that Notch signaling forms a positive feedback loop with the Hippo signaling effector YAP/TAZ to promote severe hepatomegaly and rapid HCC initiation and progression. Surprisingly, we found that Wnt/β-catenin signaling activation suppressed HCC formation by inhibiting the positive feedback loop between YAP/TAZ and Notch signaling. Furthermore, we found that STAT3 in hepatocytes is dispensable for HCC formation when mammalian sterile 20-like kinase 1 and 2 (Mst1 and Mst2) were removed. The molecular network we have identified provides insights into HCC molecular classifications and therapeutic developments for the treatment of liver tumors caused by distinct genetic mutations.

  9. TLRs, Alcohol, HCV, and Tumorigenesis

    Directory of Open Access Journals (Sweden)

    Keigo Machida

    2010-01-01

    Full Text Available Chronic liver damage caused by viral infection, alcohol, or obesity can result in increased risk for hepatocellular carcinoma (HCC. Ample epidemiological evidence suggests that there is a strong synergism between hepatitis C virus (HCV and alcoholic liver diseases (ALD. The Toll-like receptor (TLR signaling pathway is upregulated in chronic liver diseases. Alcoholism is associated with endotoxemia that stimulates expression of proinflammatory cytokine expression and inflammation in the liver and fat tissues. Recent studies of HCC have centered on cancer-initiating stem cell (CSC, including detection of CSC in cancer, identification of CSC markers, and isolation of CSC from human HCC cell lines. Synergism between alcohol and HCV may lead to liver tumorigenesis through TLR signaling.

  10. Hyperglycemia, tumorigenesis, and chronic inflammation.

    Science.gov (United States)

    Chang, Shu-Chun; Yang, Wei-Chung Vivian

    2016-12-01

    Hyperglycemia is the most prominent sign that characterizes diabetes. Hyperglycemia favors malignant cell growth by providing energy to cancer cells. Clinical studies also showed an increased risk of diabetes being associated with different types of cancers. In addition, poorly regulated glucose metabolism in diabetic patients is often found with increased levels of chronic inflammatory markers, e.g., interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α, and emerging evidence has highlighted activation of the immune response in the progression and development of cancer cells. Therefore, uncontrolled proinflammatory responses could conceivably create a chronic inflammatory state, promoting a tumor-favorable microenvironment and potentially triggering immune overactivation and cancer growth. To further understand how hyperglycemia contributes to immune overactivation, the tumor microenvironment and the development of chronic inflammation-associated tumors may provide insights into tumor biology and immunology. This paper provides a brief introduction to hyperglycemia-associated diseases, followed by a comprehensive overview of the current findings of regulatory molecular mechanisms of glycosylation on proteoglycans in the extracellular matrix under hyperglycemic conditions. Then, the authors discuss the role of hyperglycemia in tumorigenesis (particularly in prostate, liver, colorectal, and pancreatic cancers), as well as the contribution of hyperglycemia to chronic inflammation. The authors end with a brief discussion on the future perspectives of hyperglycemia/tumorigenesis and potential applications of alternative/effective therapeutic strategies for hyperglycemia-associated cancers.

  11. Ambient oxygen promotes tumorigenesis.

    Directory of Open Access Journals (Sweden)

    Ho Joong Sung

    Full Text Available Oxygen serves as an essential factor for oxidative stress, and it has been shown to be a mutagen in bacteria. While it is well established that ambient oxygen can also cause genomic instability in cultured mammalian cells, its effect on de novo tumorigenesis at the organismal level is unclear. Herein, by decreasing ambient oxygen exposure, we report a ∼50% increase in the median tumor-free survival time of p53-/- mice. In the thymus, reducing oxygen exposure decreased the levels of oxidative DNA damage and RAG recombinase, both of which are known to promote lymphomagenesis in p53-/- mice. Oxygen is further shown to be associated with genomic instability in two additional cancer models involving the APC tumor suppressor gene and chemical carcinogenesis. Together, these observations represent the first report directly testing the effect of ambient oxygen on de novo tumorigenesis and provide important physiologic evidence demonstrating its critical role in increasing genomic instability in vivo.

  12. Dietary sugar intake increases liver tumor incidence in female mice

    OpenAIRE

    Marin E. Healy; Sujoy Lahiri; Hargett, Stefan R.; Chow, Jenny D.Y.; Byrne, Frances L.; Breen, David S.; Kenwood, Brandon M.; Taddeo, Evan P.; Carolin Lackner; Caldwell, Stephen H.; Hoehn, Kyle L.

    2016-01-01

    Overnutrition can promote liver cancer in mice and humans that have liver damage caused by alcohol, viruses, or carcinogens. However, the mechanism linking diet to increased liver tumorigenesis remains unclear in the context of whether tumorigenesis is secondary to obesity, or whether nutrients like sugar or fat drive tumorigenesis independent of obesity. In male mice, liver tumor burden was recently found to correlate with sugar intake, independent of dietary fat intake and obesity. However,...

  13. Anaplastic thyroid cancer, tumorigenesis and therapy.

    LENUS (Irish Health Repository)

    O'Neill, J P

    2010-03-01

    Anaplastic thyroid cancer (ATC) is a fatal endocrine malignancy. Current therapy fails to significantly improve survival. Recent insights into thyroid tumorigenesis, post-malignant dedifferentiation and mode of metastatic activity offer new therapeutic strategies.

  14. The roles of PIKE in tumorigenesis

    Institute of Scientific and Technical Information of China (English)

    Qi QI; Keqiang YE

    2013-01-01

    Tumorigenesis is the process by which normal cells evolve the capacity to evade and overcome the constraints usually placed upon their growth and survival.To ensure the integrity of organs and tissues,the balance of cell proliferation and cell death is tightly maintained.The proteins controlling this balance are either considered oncogenes,which promote tumorigenesis,or tumor suppressors,which prevent tumorigenesis.Phosphoinositide 3-kinase enhancer (PIKE) is a family of GTP-binding proteins that possess anti-apoptotic functions and play an important role in the central nervous system.Notably,accumulating evidence suggests that PIKE is a proto-oncogene involved in tumor progression.The PIKE gene (CENTG1) is amplified in a variety of human cancers,leading to the resistance against apoptosis and the enhancement of invasion.In this review,we will summarize the functions of PIKE proteins in tumorigenesis and discuss their potential implications in cancer therapy.

  15. Dietary sugar intake increases liver tumor incidence in female mice.

    Science.gov (United States)

    Healy, Marin E; Lahiri, Sujoy; Hargett, Stefan R; Chow, Jenny D Y; Byrne, Frances L; Breen, David S; Kenwood, Brandon M; Taddeo, Evan P; Lackner, Carolin; Caldwell, Stephen H; Hoehn, Kyle L

    2016-02-29

    Overnutrition can promote liver cancer in mice and humans that have liver damage caused by alcohol, viruses, or carcinogens. However, the mechanism linking diet to increased liver tumorigenesis remains unclear in the context of whether tumorigenesis is secondary to obesity, or whether nutrients like sugar or fat drive tumorigenesis independent of obesity. In male mice, liver tumor burden was recently found to correlate with sugar intake, independent of dietary fat intake and obesity. However, females are less susceptible to developing liver cancer than males, and it remains unclear how nutrition affects tumorigenesis in females. Herein, female mice were exposed to the liver carcinogen diethylnitrosamine (DEN) and fed diets with well-defined sugar and fat content. Mice fed diets with high sugar content had the greatest liver tumor incidence while dietary fat intake was not associated with tumorigenesis. Diet-induced postprandial hyperglycemia and fasting hyperinsulinemia significantly correlated with tumor incidence, while tumor incidence was not associated with obesity and obesity-related disorders including liver steatosis, glucose intolerance, or elevated serum levels of estrogen, ALT, and lipids. These results simplify the pathophysiology of diet-induced liver tumorigenesis by focusing attention on the role of sugar metabolism and reducing emphasis on the complex milieu associated with obesity.

  16. DNA Methylation in Thyroid Tumorigenesis

    Energy Technology Data Exchange (ETDEWEB)

    Stephen, Josena K., E-mail: jstephe2@hfhs.org [Department of Otolaryngology/Head and Neck Surgery, Henry Ford Hospital, Detroit, MI 48202 (United States); Chitale, Dhananjay [Department of Pathology, Henry Ford Hospital, Detroit, MI 48202 (United States); Narra, Vinod [Essex Surgical Associates, PC, Beverly, MA 01915 (United States); Chen, Kang Mei; Sawhney, Raja; Worsham, Maria J. [Department of Otolaryngology/Head and Neck Surgery, Henry Ford Hospital, Detroit, MI 48202 (United States)

    2011-03-29

    Thyroid cancer is the most common endocrine cancer with 1,690 deaths each year. There are four main types of which the papillary and follicular types together account for >90% followed by medullary cancers with 3% to 5% and anaplastic carcinomas making up <3%. Epigenetic events of DNA hypermethylation are emerging as promising molecular targets for cancer detection. Our immediate and long term goal is to identify DNA methylation markers for early detection of thyroid cancer. This pilot study comprised of 21 patients to include 11 papillary thyroid cancers (PTC), 2 follicular thyroid cancers (FTC), 5 normal thyroid cases, and 3 hyperthyroid cases. Aberrant promoter methylation was examined in 24 tumor suppressor genes using the methylation specific multiplex ligation-dependent probe amplification (MS-MLPA) assay and in the NIS gene using methylation-specific PCR (MSP). The frequently methylated genes were CASP8 (17/21), RASSF1 (16/21) and NIS (9/21). In the normal samples, CASP8, RASSF1 and NIS were methylated in 5/5, 4/5 and 1/5 respectively. In the hyperthyroid samples, CASP8, RASSF1 and NIS were methylated in 3/3, 2/3 and 1/3 respectively. In the thyroid cancers, CASP8, RASSF1, and NIS were methylated in 9/13, 10/13, and 7/13 respectively. CASP8, RASSF1 and NIS were also methylated in concurrently present normal thyroid tissue in 3/11, 4/11 and 3/11 matched thyroid cancer cases (matched for presence of both normal thyroid tissue and thyroid cancer), respectively. Our data suggests that aberrant methylation of CASP8, RASSF1, and NIS maybe an early change in thyroid tumorigenesis regardless of cell type.

  17. IKKα activation of NOTCH links tumorigenesis via FOXA2 suppression.

    Science.gov (United States)

    Liu, Mo; Lee, Dung-Fang; Chen, Chun-Te; Yen, Chia-Jui; Li, Long-Yuan; Lee, Hong-Jen; Chang, Chun-Ju; Chang, Wei-Chao; Hsu, Jung-Mao; Kuo, Hsu-Ping; Xia, Weiya; Wei, Yongkun; Chiu, Pei-Chun; Chou, Chao-Kai; Du, Yi; Dhar, Debanjan; Karin, Michael; Chen, Chung-Hsuan; Hung, Mien-Chie

    2012-01-27

    Proinflammatory cytokine TNFα plays critical roles in promoting malignant cell proliferation, angiogenesis, and tumor metastasis in many cancers. However, the mechanism of TNFα-mediated tumor development remains unclear. Here, we show that IKKα, an important downstream kinase of TNFα, interacts with and phosphorylates FOXA2 at S107/S111, thereby suppressing FOXA2 transactivation activity and leading to decreased NUMB expression, and further activates the downstream NOTCH pathway and promotes cell proliferation and tumorigenesis. Moreover, we found that levels of IKKα, pFOXA2 (S107/111), and activated NOTCH1 were significantly higher in hepatocellular carcinoma tumors than in normal liver tissues and that pFOXA2 (S107/111) expression was positively correlated with IKKα and activated NOTCH1 expression in tumor tissues. Therefore, dysregulation of NUMB-mediated suppression of NOTCH1 by TNFα/IKKα-associated FOXA2 inhibition likely contributes to inflammation-mediated cancer pathogenesis. Here, we report a TNFα/IKKα/FOXA2/NUMB/NOTCH1 pathway that is critical for inflammation-mediated tumorigenesis and may provide a target for clinical intervention in human cancer.

  18. The TEAD Family and Its Oncogenic Role in Promoting Tumorigenesis

    Directory of Open Access Journals (Sweden)

    Yuhang Zhou

    2016-01-01

    Full Text Available The TEAD family of transcription factors is necessary for developmental processes. The family members contain a TEA domain for the binding with DNA elements and a transactivation domain for the interaction with transcription coactivators. TEAD proteins are required for the participation of coactivators to transmit the signal of pathways for the downstream signaling processes. TEADs also play an important role in tumor initiation and facilitate cancer progression via activating a series of progression-inducing genes, such as CTGF, Cyr61, Myc and Gli2. Recent studies have highlighted that TEADs, together with their coactivators, promote or even act as the crucial parts in the development of various malignancies, such as liver, ovarian, breast and prostate cancers. Furthermore, TEADs are proposed to be useful prognostic biomarkers due to the ideal correlation between high expression and clinicopathological parameters in gastric, breast, ovarian and prostate cancers. In this review, we summarize the functional role of TEAD proteins in tumorigenesis and discuss the key role of TEAD transcription factors in the linking of signal cascade transductions. Improved knowledge of the TEAD proteins will be helpful for deep understanding of the molecular mechanisms of tumorigenesis and identifying ideal predictive or prognostic biomarkers, even providing clinical translation for anticancer therapy in human cancers.

  19. The TEAD Family and Its Oncogenic Role in Promoting Tumorigenesis.

    Science.gov (United States)

    Zhou, Yuhang; Huang, Tingting; Cheng, Alfred S L; Yu, Jun; Kang, Wei; To, Ka Fai

    2016-01-21

    The TEAD family of transcription factors is necessary for developmental processes. The family members contain a TEA domain for the binding with DNA elements and a transactivation domain for the interaction with transcription coactivators. TEAD proteins are required for the participation of coactivators to transmit the signal of pathways for the downstream signaling processes. TEADs also play an important role in tumor initiation and facilitate cancer progression via activating a series of progression-inducing genes, such as CTGF, Cyr61, Myc and Gli2. Recent studies have highlighted that TEADs, together with their coactivators, promote or even act as the crucial parts in the development of various malignancies, such as liver, ovarian, breast and prostate cancers. Furthermore, TEADs are proposed to be useful prognostic biomarkers due to the ideal correlation between high expression and clinicopathological parameters in gastric, breast, ovarian and prostate cancers. In this review, we summarize the functional role of TEAD proteins in tumorigenesis and discuss the key role of TEAD transcription factors in the linking of signal cascade transductions. Improved knowledge of the TEAD proteins will be helpful for deep understanding of the molecular mechanisms of tumorigenesis and identifying ideal predictive or prognostic biomarkers, even providing clinical translation for anticancer therapy in human cancers.

  20. TAK1-mediated autophagy and fatty acid oxidation prevent hepatosteatosis and tumorigenesis.

    Science.gov (United States)

    Inokuchi-Shimizu, Sayaka; Park, Eek Joong; Roh, Yoon Seok; Yang, Ling; Zhang, Bi; Song, Jingyi; Liang, Shuang; Pimienta, Michael; Taniguchi, Koji; Wu, Xuefeng; Asahina, Kinji; Lagakos, William; Mackey, Mason R; Akira, Shizuo; Ellisman, Mark H; Sears, Dorothy D; Olefsky, Jerrold M; Karin, Michael; Brenner, David A; Seki, Ekihiro

    2014-08-01

    The MAP kinase kinase kinase TGFβ-activated kinase 1 (TAK1) is activated by TLRs, IL-1, TNF, and TGFβ and in turn activates IKK-NF-κB and JNK, which regulate cell survival, growth, tumorigenesis, and metabolism. TAK1 signaling also upregulates AMPK activity and autophagy. Here, we investigated TAK1-dependent regulation of autophagy, lipid metabolism, and tumorigenesis in the liver. Fasted mice with hepatocyte-specific deletion of Tak1 exhibited severe hepatosteatosis with increased mTORC1 activity and suppression of autophagy compared with their WT counterparts. TAK1-deficient hepatocytes exhibited suppressed AMPK activity and autophagy in response to starvation or metformin treatment; however, ectopic activation of AMPK restored autophagy in these cells. Peroxisome proliferator-activated receptor α (PPARα) target genes and β-oxidation, which regulate hepatic lipid degradation, were also suppressed in hepatocytes lacking TAK1. Due to suppression of autophagy and β-oxidation, a high-fat diet challenge aggravated steatohepatitis in mice with hepatocyte-specific deletion of Tak1. Notably, inhibition of mTORC1 restored autophagy and PPARα target gene expression in TAK1-deficient livers, indicating that TAK1 acts upstream of mTORC1. mTORC1 inhibition also suppressed spontaneous liver fibrosis and hepatocarcinogenesis in animals with hepatocyte-specific deletion of Tak1. These data indicate that TAK1 regulates hepatic lipid metabolism and tumorigenesis via the AMPK/mTORC1 axis, affecting both autophagy and PPARα activity.

  1. Complexity, dynamic cellular network, and tumorigenesis.

    Science.gov (United States)

    Waliszewski, P

    1997-01-01

    A holistic approach to tumorigenesis is proposed. The main element of the model is the existence of dynamic cellular network. This network comprises a molecular and an energetistic structure of a cell connected through the multidirectional flow of information. The interactions within dynamic cellular network are complex, stochastic, nonlinear, and also involve quantum effects. From this non-reductionist perspective, neither tumorigenesis can be limited to the genetic aspect, nor the initial event must be of molecular nature, nor mutations and epigenetic factors are mutually exclusive, nor a link between cause and effect can be established. Due to complexity, an unstable stationary state of dynamic cellular network rather than a group of unrelated genes determines the phenotype of normal and transformed cells. This implies relativity of tumor suppressor genes and oncogenes. A bifurcation point is defined as an unstable state of dynamic cellular network leading to the other phenotype-stationary state. In particular, the bifurcation point may be determined by a change of expression of a single gene. Then, the gene is called bifurcation point gene. The unstable stationary state facilitates the chaotic dynamics. This may result in a fractal dimension of both normal and tumor tissues. The co-existence of chaotic dynamics and complexity is the essence of cellular processes and shapes differentiation, morphogenesis, and tumorigenesis. In consequence, tumorigenesis is a complex, unpredictable process driven by the interplay between self-organisation and selection.

  2. The gut microbiome modulates colon tumorigenesis.

    Science.gov (United States)

    Zackular, Joseph P; Baxter, Nielson T; Iverson, Kathryn D; Sadler, William D; Petrosino, Joseph F; Chen, Grace Y; Schloss, Patrick D

    2013-11-05

    Recent studies have shown that individuals with colorectal cancer have an altered gut microbiome compared to healthy controls. It remains unclear whether these differences are a response to tumorigenesis or actively drive tumorigenesis. To determine the role of the gut microbiome in the development of colorectal cancer, we characterized the gut microbiome in a murine model of inflammation-associated colorectal cancer that mirrors what is seen in humans. We followed the development of an abnormal microbial community structure associated with inflammation and tumorigenesis in the colon. Tumor-bearing mice showed enrichment in operational taxonomic units (OTUs) affiliated with members of the Bacteroides, Odoribacter, and Akkermansia genera and decreases in OTUs affiliated with members of the Prevotellaceae and Porphyromonadaceae families. Conventionalization of germfree mice with microbiota from tumor-bearing mice significantly increased tumorigenesis in the colon compared to that for animals colonized with a healthy gut microbiome from untreated mice. Furthermore, at the end of the model, germfree mice colonized with microbiota from tumor-bearing mice harbored a higher relative abundance of populations associated with tumor formation in conventional animals. Manipulation of the gut microbiome with antibiotics resulted in a dramatic decrease in both the number and size of tumors. Our results demonstrate that changes in the gut microbiome associated with inflammation and tumorigenesis directly contribute to tumorigenesis and suggest that interventions affecting the composition of the microbiome may be a strategy to prevent the development of colon cancer. The trillions of bacteria that live in the gut, known collectively as the gut microbiome, are important for normal functioning of the intestine. There is now growing evidence that disruptive changes in the gut microbiome are strongly associated with the development colorectal cancer. However, how the gut microbiome

  3. Inhibition of lung tumorigenesis by tea.

    Science.gov (United States)

    Yang, Chung S; Liao, Jie; Yang, Guang-yu; Lu, Gary

    2005-01-01

    Tea and tea constituents have been shown by different investigators to inhibit lung tumorigenesis in different animal model systems. This includes lung tumorigenesis in A/J mice induced by 4-(methylnitrosamino)-1-(3pyridyl)-1-butanone (NNK), N-nitrosodiethylamine, benzo[a]pyrene, N-nitrosomethylurea, or cisplatin. Inhibition of lung tumorigenesis has also been demonstrated in C3H mice treated with N-nitrosodiethylamine. In most of these experiments, reduction in tumor number and tumor size has been observed in the tea-treated group, and in some experiments, decreased tumor incidence has also been observed. The green tea constituent, epigallocatechin-3-gallate (EGCG), and the black tea constituent, theaflavins, have also been shown to be effective. Black tea preparations have been shown to reduce the incidence and number of spontaneously generated lung adenocarcinomas and rhabdomyosarcoma in A/J mice, as well as inhibit the progression of lung adenoma to adenocarcinoma. The mechanisms for the inhibitory action have not been well elucidated. It may be related to the antiproliferative, proapoptotic, and antiangiogenic activities of tea constituents that have been demonstrated in some experiments. These activities may be a result of the inhibition of key protein kinases involved in signal transduction and cell cycle regulation. Tea catechins, such as EGCG, have been suggested to be the effective components. However, a study suggests that caffeine is the key effective constituent for the inhibitory activity of lung tumorigenesis in Fisher 344 rats by black tea. In many of the experiments, tea consumption resulted in the reduction of body fat and body weight; these factors may also contribute to the inhibition of tumorigenesis.

  4. Clinical and molecular insights into primary pediatric liver cancer

    NARCIS (Netherlands)

    V.B. Weeda

    2016-01-01

    This thesis aims to give insight into the clinical status quo of primary pediatric liver tumors and investigate signaling pathways that may be of importance for liver tumorigenesis. The most recent series of the International Childhood Liver Tumors Strategy Group (SIOPEL) of hepatocellular carcinoma

  5. Lymphotoxin signaling is initiated by the viral polymerase in HCV-linked tumorigenesis.

    Directory of Open Access Journals (Sweden)

    Yannick Simonin

    2013-03-01

    Full Text Available Exposure to hepatitis C virus (HCV typically results in chronic infection that leads to progressive liver disease ranging from mild inflammation to severe fibrosis and cirrhosis as well as primary liver cancer. HCV triggers innate immune signaling within the infected hepatocyte, a first step in mounting of the adaptive response against HCV infection. Persistent inflammation is strongly associated with liver tumorigenesis. The goal of our work was to investigate the initiation of the inflammatory processes triggered by HCV viral proteins in their host cell and their possible link with HCV-related liver cancer. We report a dramatic upregulation of the lymphotoxin signaling pathway and more specifically of lymphotoxin-β in tumors of the FL-N/35 HCV-transgenic mice. Lymphotoxin expression is accompanied by activation of NF-κB, neosynthesis of chemokines and intra-tumoral recruitment of mononuclear cells. Spectacularly, IKKβ inactivation in FL-N/35 mice drastically reduces tumor incidence. Activation of lymphotoxin-β pathway can be reproduced in several cellular models, including the full length replicon and HCV-infected primary human hepatocytes. We have identified NS5B, the HCV RNA dependent RNA polymerase, as the viral protein responsible for this phenotype and shown that pharmacological inhibition of its activity alleviates activation of the pro-inflammatory pathway. These results open new perspectives in understanding the inflammatory mechanisms linked to HCV infection and tumorigenesis.

  6. Menin represses tumorigenesis via repressing cell proliferation

    OpenAIRE

    Wu, Ting; Hua, Xianxin

    2011-01-01

    Multiple endocrine neoplasia type 1 (MEN1) results from mutations in the tumor suppressor gene, MEN1, which encodes nuclear protein menin. Menin is important for suppressing tumorigenesis in various endocrine and certain non-endocrine tissues. Although menin suppresses MEN1 through a variety of mechanisms including regulating apoptosis and DNA repair, the role of menin in regulating cell proliferation is one of the best-studied functions. Here, we focus on reviewing various mechanisms underly...

  7. Inactivating CUX1 mutations promote tumorigenesis

    OpenAIRE

    2013-01-01

    A major challenge for cancer genetics is to determine which low frequency somatic mutations are drivers of tumorigenesis. Here we interrogate the genomes of 7,651 diverse human cancers to identify novel drivers and find inactivating mutations in the homeodomain transcription factor CUX1 (cut-like homeobox 1) in ~1-5% of tumors. Meta-analysis of CUX1 mutational status in 2,519 cases of myeloid malignancies reveals disruptive mutations associated with poor survival, highlighting the clinical si...

  8. Role of Mesenchymal Stem Cells In Tumorigenesis

    Science.gov (United States)

    2009-08-01

    stem cells ( BMDC ), which then acts in a paracrine fashion on the cancer cells to enhance their invasion [7]. Interestingly the group of Karnoub showed...AD_________________ AWARD NUMBER: W81XWH-08-1-0523 TITLE: Role of Mesenchymal Stem Cells in...DATES COVERED 1 Aug 2008 – 31 Jul 2009 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Role of Mesenchymal Stem Cells in Tumorigenesis 5b. GRANT

  9. Innate lymphoid cells involve in tumorigenesis.

    Science.gov (United States)

    Tian, Zhiqiang; van Velkinburgh, Jennifer C; Wu, Yuzhang; Ni, Bing

    2016-01-01

    Innate lymphoid cells (ILCs) promptly initiate cytokine responses to pathogen exposure in the mucosa and mucosal-associated lymphoid tissues. ILCs were recently categorized as being of the lymphoid lineage and have been classified into three groups. ILCs play important roles in immunity against pathogens, and an anti-tumor immune-related function was recently demonstrated. In this review we discuss whether and how ILCs involve in the tumorigenesis, providing new insights into the mechanisms underlying the particular functions of ILCs as well as the potential targets for tumor intervention.

  10. Peroxiredoxin I is important for cancer-cell survival in Ras-induced hepatic tumorigenesis.

    Science.gov (United States)

    Han, Bing; Shin, Hye-Jun; Bak, In Seon; Bak, Yesol; Jeong, Ye-Lin; Kwon, Taeho; Park, Young-Ho; Sun, Hu-Nan; Kim, Cheol-Hee; Yu, Dae-Yeul

    2016-10-18

    Peroxiredoxin I (Prx I), an antioxidant enzyme, has multiple functions in human cancer. However, the role of Prx I in hepatic tumorigenesis has not been characterized. Here we investigated the relevance and underlying mechanism of Prx I in hepatic tumorigenesis. Prx I increased in tumors of hepatocellular carcinoma (HCC) patients that aligned with overexpression of oncogenic H-ras. Prx I also increased in H-rasG12V transfected HCC cells and liver tumors of H-rasG12V transgenic (Tg) mice, indicating that Prx I may be involved in Ras-induced hepatic tumorigenesis. When Prx I was knocked down or deleted in HCC-H-rasG12V cells or H-rasG12V Tg mice, cell colony or tumor formation was significantly reduced that was associated with downregulation of pERK pathway as well as increased intracellular reactive oxygen species (ROS) induced DNA damage and cell death. Overexpressing Prx I markedly increased Ras downstream pERK/FoxM1/Nrf2 signaling pathway and inhibited oxidative damage in HCC cells and H-rasG12V Tg mice. In this study, we found Nrf2 was transcriptionally activated by FoxM1, and Prx I was activated by the H-rasG12V/pERK/FoxM1/Nrf2 pathway and suppressed ROS-induced hepatic cancer-cell death along with formation of a positive feedback loop with Ras/ERK/FoxM1/Nrf2 to promote hepatic tumorigenesis.

  11. Liver transplant

    Science.gov (United States)

    Hepatic transplant; Transplant - liver; Orthotopic liver transplant; Liver failure - liver transplant; Cirrhosis - liver transplant ... The donated liver may be from: A donor who has recently died and has not had liver injury. This type of ...

  12. Roles of sphingosine 1-phosphate on tumorigenesis

    Institute of Scientific and Technical Information of China (English)

    Hsinyu; Lee

    2011-01-01

    Sphingosine 1-phosphate (S1P) is a bioactive sphingolipid with a variety of biological activities.It is generated from the conversion of ceramide to sphingosine by ceramidase and the subsequent conversion of sphingosine to S1P,which is catalyzed by sphingosine kinases.Through increasing its intracellular levels by sphingolipid metabolism and binding to its cell surface receptors,S1P regulates several physiological and pathological processes,including cell proliferation,migration,angiogenesis and autophagy.These processes are responsible for tumor growth,metastasis and invasion and promote tumor survival.Since ceramide and S1P have distinct functions in regulating in cell fate decision,the balance between the ceramide/sphingosine/S1P rheostat becomes a potent therapeutic target for cancer cells.Herein,we summarize our current understanding of S1P signaling on tumorigenesis and its potential as a target for cancer therapy.

  13. The role of menin in parathyroid tumorigenesis.

    LENUS (Irish Health Repository)

    Davenport, Colin

    2009-01-01

    Primary hyperparathyroidism is a common disorder that involves the pathological enlargement of one or more parathyroid glands resulting in excessive production of parathyroid hormone (PTH). The exact pathogenesis of this disease remains to be fully understood. In recent years interest has focussed on the interaction between menin protein and the transforming growth factor (TGF)-beta\\/Smad signalling pathway. In vitro experimentation has demonstrated that the presence of menin is required for TGF-beta to effectively inhibit parathyroid cell proliferation and PTH production. This observation correlates with the almost universal occurrence of parathyroid tumors accompanying the inactivation of menin in multiple endocrine neoplasia Type 1 (MEN1) syndrome and the high rate of somatic menin gene mutations seen in sporadic parathyroid adenomas. This chapter aims to review the role of menin in primary hyperparathyroidism and parathyroid hormone-regulation, including the influences of MEN1 gene mutations on parathyroid cell proliferation, differentiation and tumorigenesis.

  14. The p130 isoform of angiomotin is required for Yap-mediated hepatic epithelial cell proliferation and tumorigenesis.

    Science.gov (United States)

    Yi, Chunling; Shen, Zhewei; Stemmer-Rachamimov, Anat; Dawany, Noor; Troutman, Scott; Showe, Louise C; Liu, Qin; Shimono, Akihiko; Sudol, Marius; Holmgren, Lars; Stanger, Ben Z; Kissil, Joseph L

    2013-09-03

    The Hippo-Yap signaling pathway regulates a number of developmental and adult cellular processes, including cell fate determination, tissue growth, and tumorigenesis. Members of the scaffold protein angiomotin (Amot) family interact with several Hippo pathway components, including Yap (Yes-associated protein), and either stimulate or inhibit Yap activity. We used a combination of genetic, biochemical, and transcriptional approaches to assess the functional consequences of the Amot-Yap interaction in mice and in human cells. Mice with a liver-specific Amot knockout exhibited reduced hepatic "oval cell" proliferation and tumorigenesis in response to toxin-induced injury or when crossed with mice lacking the tumor suppressor Nf2. Biochemical examination of the Amot-Yap interaction revealed that the p130 splicing isoform of Amot (Amot-p130) and Yap interacted in both the cytoplasm and nucleus, which involved binding of PPxY and LPxY motifs in Amot-p130 to WW domains of Yap. In the cytoplasm, Amot-p130 prevented the phosphorylation of Yap by blocking access of the WW domains to the kinase Lats1. Within the nucleus, Amot-p130 was associated with the transcriptional complex containing Yap and Teads (TEA domain family members) and contributed to the regulation of a subset of Yap target genes, many of which are associated with tumorigenesis. These findings indicated that Amot acts as a Yap cofactor, preventing Yap phosphorylation and augmenting its activity toward a specific set of genes that facilitate tumorigenesis.

  15. MicroRNA signatures in liver diseases

    OpenAIRE

    Chen, Xian-Ming

    2009-01-01

    MicroRNAs (miRNAs) are an emerging class of highly conserved non-coding small RNAs that regulate gene expression at the post-transcriptional level. It is now clear that miRNAs can potentially regulate every aspect of cellular activity, including differentiation and development, metabolism, proliferation, apoptotic cell death, viral infection and tumorigenesis. Recent studies provide clear evidence that miRNAs are abundant in the liver and modulate a diverse spectrum of liver functions. Deregu...

  16. Implications of mitochondrial DNA mutations and mitochondrial dysfunction in tumorigenesis

    Institute of Scientific and Technical Information of China (English)

    Jianxin Lu; Lokendra Kumar Sharma; Yidong Bai

    2009-01-01

    Alterations in oxidative phosphorylation resulting from mitochondrial dysfunction have long been hypothesized to be involved in tumorigenesis. Mitochondria have recently been shown to play an important role in regulating both programmed cell death and cell proliferation. Furthermore, mitochondrial DNA (mtDNA) mutations have been found in various cancer cells. However, the role of these mtDNA mutations in tumorigenesis remains largely unknown. This review focuses on basic mitochondrial genetics, mtDNA mutations and consequential mitochondrial dysfunction associated with cancer. The potential molecular mechanisms, mediating the pathogenesis from mtDNA mutations and mitochondrial dysfunction to tumorigenesis are also discussed.

  17. Cited1 deficiency suppresses intestinal tumorigenesis.

    Directory of Open Access Journals (Sweden)

    Valérie Méniel

    Full Text Available Conditional deletion of Apc in the murine intestine alters crypt-villus architecture and function. This process is accompanied by multiple changes in gene expression, including upregulation of Cited1, whose role in colorectal carcinogenesis is unknown. Here we explore the relevance of Cited1 to intestinal tumorigenesis. We crossed Cited1 null mice with Apc(Min/+ and AhCre(+Apc(fl/fl mice and determined the impact of Cited1 deficiency on tumour growth/initiation including tumour multiplicity, cell proliferation, apoptosis and the transcriptome. We show that Cited1 is up-regulated in both human and murine tumours, and that constitutive deficiency of Cited1 increases survival in Apc(Min/+ mice from 230.5 to 515 days. However, paradoxically, Cited1 deficiency accentuated nearly all aspects of the immediate phenotype 4 days after conditional deletion of Apc, including an increase in cell death and enhanced perturbation of differentiation, including of the stem cell compartment. Transcriptome analysis revealed multiple pathway changes, including p53, PI3K and Wnt. The activation of Wnt through Cited1 deficiency correlated with increased transcription of β-catenin and increased levels of dephosphorylated β-catenin. Hence, immediately following deletion of Apc, Cited1 normally restrains the Wnt pathway at the level of β-catenin. Thus deficiency of Cited1 leads to hyper-activation of Wnt signaling and an exaggerated Wnt phenotype including elevated cell death. Cited1 deficiency decreases intestinal tumourigenesis in Apc(Min/+ mice and impacts upon a number of oncogenic signaling pathways, including Wnt. This restraint imposed by Cited1 is consistent with a requirement for Cited1 to constrain Wnt activity to a level commensurate with optimal adenoma formation and maintenance, and provides one mechanism for tumour repression in the absence of Cited1.

  18. MicroRNA-186 targets Yes-associated protein 1 to inhibit Hippo signaling and tumorigenesis in hepatocellular carcinoma.

    Science.gov (United States)

    Ruan, Tingyan; He, Xiaoting; Yu, Jun; Hang, Zhiqiang

    2016-04-01

    Liver cancer, particularly hepatocellular carcinoma (HCC), is one of leading causes of cancer-related mortality worldwide. Upregulation of the evolutionary conserved Hippo signaling pathway has been observed in HCC patients, and Yes-associated protein 1 (YAP1) has been reported to play a key role in HCC tumorigenesis. microRNAs (miRNAs) are a family of small non-coding RNAs, usually 21-25 nucleotides in length, and are essential in the regulation of gene expression. Abnormal miRNA expression has been implicated in the initiation and progression of numerous forms of cancers, including liver cancer. Here, we report the identification of a novel miRNA, miR-186, and its functions as an HCC tumor suppressor. We observed that miR-186 was downregulated in several HCC cell lines, and that it directly targets YAP1 mRNA. Overexpression of miR-186 in HCC cells significantly downregulates YAP1 mRNA and protein levels, leading to downregulation of the Hippo signaling pathway, which in turn severely inhibits HCC cell migration, invasion and proliferation. Our study is the first to report the direct involvement of miR-186 in downregulating YAP1 and, more significantly, inhibiting HCC tumorigenesis, and supports the role miR-186 as a potential therapeutic target in treating liver cancer.

  19. piggyBac mediates efficient in vivo CRISPR library screening for tumorigenesis in mice.

    Science.gov (United States)

    Xu, Chunlong; Qi, Xiaolan; Du, Xuguang; Zou, Huiying; Gao, Fei; Feng, Tao; Lu, Hengxing; Li, Shenglan; An, Xiaomeng; Zhang, Lijun; Wu, Yuanyuan; Liu, Ying; Li, Ning; Capecchi, Mario R; Wu, Sen

    2017-01-24

    CRISPR/Cas9 is becoming an increasingly important tool to functionally annotate genomes. However, because genome-wide CRISPR libraries are mostly constructed in lentiviral vectors, in vivo applications are severely limited as a result of difficulties in delivery. Here, we examined the piggyBac (PB) transposon as an alternative vehicle to deliver a guide RNA (gRNA) library for in vivo screening. Although tumor induction has previously been achieved in mice by targeting cancer genes with the CRISPR/Cas9 system, in vivo genome-scale screening has not been reported. With our PB-CRISPR libraries, we conducted an in vivo genome-wide screen in mice and identified genes mediating liver tumorigenesis, including known and unknown tumor suppressor genes (TSGs). Our results demonstrate that PB can be a simple and nonviral choice for efficient in vivo delivery of CRISPR libraries.

  20. Mitochondrial DNA plasticity is an essential inducer of tumorigenesis.

    Science.gov (United States)

    Lee, W T Y; Cain, J E; Cuddihy, A; Johnson, J; Dickinson, A; Yeung, K-Y; Kumar, B; Johns, T G; Watkins, D N; Spencer, A; St John, J C

    2016-01-01

    Although mitochondrial DNA has been implicated in diseases such as cancer, its role remains to be defined. Using three models of tumorigenesis, namely glioblastoma multiforme, multiple myeloma and osteosarcoma, we show that mitochondrial DNA plays defining roles at early and late tumour progression. Specifically, tumour cells partially or completely depleted of mitochondrial DNA either restored their mitochondrial DNA content or actively recruited mitochondrial DNA, which affected the rate of tumorigenesis. Nevertheless, non-depleted tumour cells modulated mitochondrial DNA copy number at early and late progression in a mitochondrial DNA genotype-specific manner. In glioblastoma multiforme and osteosarcoma, this was coupled with loss and gain of mitochondrial DNA variants. Changes in mitochondrial DNA genotype affected tumour morphology and gene expression patterns at early and late progression. Importantly, this identified a subset of genes that are essential to early progression. Consequently, mitochondrial DNA and commonly expressed early tumour-specific genes provide novel targets against tumorigenesis.

  1. Controversies about the genetic model of colorectal tumorigenesis.

    Science.gov (United States)

    Waliszewski, P

    1995-01-01

    According to the genetic model, intestinal tumorigenesis is a result of the ordered in time inactivation of tumor suppressor genes and the activation of oncogenes. A tacit assumption is that both genes involved in the regulation of proliferation and growth factor-inducible genes, although inactivated, would not be changed during that process. The model requires that cancer cell population is homogenous, exists in a deterministic environment, and develops in a teleological manner. Meanwhile, tumorigenesis is rather a combination of both deterministic and stochastic molecular phenomena. Therefore, a novel notion of bifurcating point genes is defined as a generalization of the idea of tumor suppressor genes and oncogenes. Alternative stochastic mechanisms of tumorigenesis are discussed such as a decreased expression of intestinal-specific genes in cancer cells, most likely reflecting adaptation to survival within a heterogeneous, and non-equilibrated cellular population.

  2. Germline Mutations in Mtap Cooperate with Myc to Accelerate Tumorigenesis in Mice.

    Directory of Open Access Journals (Sweden)

    Yuwaraj Kadariya

    Full Text Available The gene encoding the methionine salvage pathway methylthioadenosine phosphorylase (MTAP is a tumor suppressor gene that is frequently inactivated in a wide variety of human cancers. In this study, we have examined if heterozygosity for a null mutation in Mtap (Mtap(lacZ could accelerate tumorigenesis development in two different mouse cancer models, Eμ-myc transgenic and Pten(+/- .Mtap Eμ-myc and Mtap Pten mice were generated and tumor-free survival was monitored over time. Tumors were also examined for a variety of histological and protein markers. In addition, microarray analysis was performed on the livers of Mtap(lacZ/+ and Mtap (+/+ mice.Survival in both models was significantly decreased in Mtap(lacZ/+ compared to Mtap(+/+ mice. In Eµ-myc mice, Mtap mutations accelerated the formation of lymphomas from cells in the early pre-B stage, and these tumors tended to be of higher grade and have higher expression levels of ornithine decarboxylase compared to those observed in control Eµ-myc Mtap(+/+ mice. Surprisingly, examination of Mtap status in lymphomas in Eµ-myc Mtap(lacZ/+ and Eµ-myc Mtap(+/+ animals did not reveal significant differences in the frequency of loss of Mtap protein expression, despite having shorter latency times, suggesting that haploinsufficiency of Mtap may be playing a direct role in accelerating tumorigenesis. Consistent with this idea, microarray analysis on liver tissue from age and sex matched Mtap(+/+ and Mtap(lacZ/+ animals found 363 transcripts whose expression changed at least 1.5-fold (P<0.01. Functional categorization of these genes reveals enrichments in several pathways involved in growth control and cancer.Our findings show that germline inactivation of a single Mtap allele alters gene expression and enhances lymphomagenesis in Eµ-myc mice.

  3. Partial Hepatectomy in Acetylation-Deficient Mice Corroborates that Chromosome Missegregation Initiates Tumorigenesis

    Directory of Open Access Journals (Sweden)

    Yoo-Kyung Lee

    2014-12-01

    Full Text Available BackgroundAneuploidy has been suggested as one of the major causes of cancer from the time of Boveri. In support of this notion, many studies have shown that cancer cells exhibit aneuploidy. However, there are evidences that do not support the aneuploidy hypothesis. We have previously reported that the spindle assembly checkpoint protein BubR1 is acetylated in mitosis and that the acetylation of BubR1 is crucial for checkpoint maintenance and chromosome-spindle attachment. Mice heterozygous for acetylation-deficient BubR1 (K243R/+ spontaneously develop cancer with chromosome instability. As K243R/+ mice develop hepatocellular carcinoma, we set out to test if chromosome mis-segregation was the cause of their liver cancer.MethodsPrimary hepatocytes in the regenerating liver after partial hepatectomy (PH were analyzed and compared for various mitotic parameters.ResultsPrimary hepatocytes isolated from K243R/+ mice after PH displayed a marked increase of chromosome misalignment, accompanied by an increase of micronuclei. In comparison, the number of nuclei per cell and the centrosome numbers were not different between wild-type and K243R/+ mice. Taken together, chromosome mis-segregation provokes tumorigenesis in mouse liver.ConclusionOur results corroborate that PH provides a reliable tool for assessing mitotic infidelity and cancer in mice.

  4. DSS colitis promotes tumorigenesis and fibrogenesis in a choline-deficient high-fat diet-induced NASH mouse model.

    Science.gov (United States)

    Achiwa, Koichi; Ishigami, Masatoshi; Ishizu, Yoji; Kuzuya, Teiji; Honda, Takashi; Hayashi, Kazuhiko; Hirooka, Yoshiki; Katano, Yoshiaki; Goto, Hidemi

    2016-01-29

    Nonalcoholic steatohepatitis (NASH) patients progress to liver cirrhosis and even hepatocellular carcinoma (HCC). Several lines of evidence indicate that accumulation of lipopolysaccharide (LPS) and disruption of gut microbiota play contributory roles in HCC. Moreover, in a dextran sodium sulfate (DSS)-induced colitis model in mice, a high-fat diet increases portal LPS level and promotes hepatic inflammation and fibrosis. However, this diet-induced NASH model requires at least 50 weeks for carcinogenesis. In this study, we sought to determine whether increased intestinal permeability would aggravate liver inflammation and fibrosis and accelerate tumorigenesis in a diet-induced NASH model. Mice were fed a choline-deficient high-fat (CDHF) diet for 4 or 12 weeks. The DSS group was fed CDHF and intermittently received 1% DSS in the drinking water. Exposure to DSS promoted mucosal changes such as crypt loss and increased the number of inflammatory cells in the colon. In the DSS group, portal LPS levels were elevated at 4 weeks, and the proportions of Clostridium cluster XI in the fecal microbiota were elevated. In addition, levels of serum transaminase, number of lobular inflammatory cells, F4/80 staining-positive area, and levels of inflammatory cytokines were all elevated in the DSS group. Liver histology in the DSS group revealed severe fibrosis at 12 weeks. Liver tumors were detected in the DSS group at 12 weeks, but not in the other groups. Thus, DSS administration promoted liver tumors in a CDHF diet-induced NASH mouse over the short term, suggesting that the induction of intestinal inflammation and gut disruption of microbiota in NASH promote hepatic tumorigenesis.

  5. Liver Facts

    Science.gov (United States)

    ... Lung Kidney Pancreas Kidney/Pancreas Liver Intestine Liver Facts How the Liver Works The liver is one ... Camps for kids Contacting my donor family Data Facts about living donation Financing a transplant Matching organs ...

  6. A critical reassessment of the role of mitochondria in tumorigenesis.

    Directory of Open Access Journals (Sweden)

    Antonio Salas

    2005-11-01

    Full Text Available BACKGROUND: Mitochondrial DNA (mtDNA is being analyzed by an increasing number of laboratories in order to investigate its potential role as an active marker of tumorigenesis in various types of cancer. Here we question the conclusions drawn in most of these investigations, especially those published in high-rank cancer research journals, under the evidence that a significant number of these medical mtDNA studies are based on obviously flawed sequencing results. METHODS AND FINDINGS: In our analyses, we take a phylogenetic approach and employ thorough database searches, which together have proven successful for detecting erroneous sequences in the fields of human population genetics and forensics. Apart from conceptual problems concerning the interpretation of mtDNA variation in tumorigenesis, in most cases, blocks of seemingly somatic mutations clearly point to contamination or sample mix-up and, therefore, have nothing to do with tumorigenesis. CONCLUSION: The role of mitochondria in tumorigenesis remains unclarified. Our findings of laboratory errors in many contributions would represent only the tip of the iceberg since most published studies do not provide the raw sequence data for inspection, thus hindering a posteriori evaluation of the results. There is no precedent for such a concatenation of errors and misconceptions affecting a whole subfield of medical research.

  7. Manipulation of the Gut Microbiota Reveals Role in Colon Tumorigenesis

    Science.gov (United States)

    Zackular, Joseph P.; Baxter, Nielson T.

    2015-01-01

    ABSTRACT There is growing evidence that individuals with colonic adenomas and carcinomas harbor a distinct microbiota. Alterations to the gut microbiota may allow the outgrowth of bacterial populations that induce genomic mutations or exacerbate tumor-promoting inflammation. In addition, it is likely that the loss of key bacterial populations may result in the loss of protective functions that are normally provided by the microbiota. We explored the role of the gut microbiota in colon tumorigenesis by using an inflammation-based murine model. We observed that perturbing the microbiota with different combinations of antibiotics reduced the number of tumors at the end of the model. Using the random forest machine learning algorithm, we successfully modeled the number of tumors that developed over the course of the model on the basis of the initial composition of the microbiota. The timing of antibiotic treatment was an important determinant of tumor outcome, as colon tumorigenesis was arrested by the use of antibiotics during the early inflammation period of the murine model. Together, these results indicate that it is possible to predict colon tumorigenesis on the basis of the composition of the microbiota and that altering the gut microbiota can alter the course of tumorigenesis. IMPORTANCE Mounting evidence indicates that alterations to the gut microbiota, the complex community of bacteria that inhabits the gastrointestinal tract, are strongly associated with the development of colorectal cancer. We used antibiotic perturbations to a murine model of inflammation-driven colon cancer to generate eight starting communities that resulted in various severities of tumorigenesis. Furthermore, we were able to quantitatively predict the final number of tumors on the basis of the initial composition of the gut microbiota. These results further bolster the evidence that the gut microbiota is involved in mediating the development of colorectal cancer. As a final proof of

  8. Autophagy mitigates metabolic stress and genome damage in mammary tumorigenesis

    Science.gov (United States)

    Karantza-Wadsworth, Vassiliki; Patel, Shyam; Kravchuk, Olga; Chen, Guanghua; Mathew, Robin; Jin, Shengkan; White, Eileen

    2007-01-01

    Autophagy is a catabolic process involving self-digestion of cellular organelles during starvation as a means of cell survival; however, if it proceeds to completion, autophagy can lead to cell death. Autophagy is also a haploinsufficient tumor suppressor mechanism for mammary tumorigenesis, as the essential autophagy regulator beclin1 is monoallelically deleted in breast carcinomas. However, the mechanism by which autophagy suppresses breast cancer remains elusive. Here we show that allelic loss of beclin1 and defective autophagy sensitized mammary epithelial cells to metabolic stress and accelerated lumen formation in mammary acini. Autophagy defects also activated the DNA damage response in vitro and in mammary tumors in vivo, promoted gene amplification, and synergized with defective apoptosis to promote mammary tumorigenesis. Therefore, we propose that autophagy limits metabolic stress to protect the genome, and that defective autophagy increases DNA damage and genomic instability that ultimately facilitate breast cancer progression. PMID:17606641

  9. CUEDC2: an emerging key player in inflammation and tumorigenesis

    Institute of Scientific and Technical Information of China (English)

    Jianghong Man; Xuemin Zhang

    2011-01-01

    CUE domain-containing 2 (CUEDC2) is a protein involved in the regulation of the cell cycle,inflammation,and tumorigenesis and is highly expressed in many types of tumors.CUEDC2 is phosphorylated by Cdk1 during mitosis and promotes the release of anaphase-promoting complex or cyclosome (APC/C) from checkpoint inhibition.CUEDC2 is also known to interact with IkB kinase α (IKKα) and IKKβ and has an inhibitory role in the activation of transcription factor nuclear factor-κB.Moreover,CUEDC2 plays an important role in downregulating the expression of hormone receptors estrogen receptorα and progesterone receptor,thereby impairing the responsiveness of breast cancer to endocrine therapies.In this review,current knowledge on the multi-functions of CUEDC2 in normal processes and tumorigenesis are discussed and summarized.

  10. Non-metabolic functions of glycolytic enzymes in tumorigenesis.

    Science.gov (United States)

    Yu, X; Li, S

    2017-05-11

    Cancer cells reprogram their metabolism to meet the requirement for survival and rapid growth. One hallmark of cancer metabolism is elevated aerobic glycolysis and reduced oxidative phosphorylation. Emerging evidence showed that most glycolytic enzymes are deregulated in cancer cells and play important roles in tumorigenesis. Recent studies revealed that all essential glycolytic enzymes can be translocated into nucleus where they participate in tumor progression independent of their canonical metabolic roles. These noncanonical functions include anti-apoptosis, regulation of epigenetic modifications, modulation of transcription factors and co-factors, extracellular cytokine, protein kinase activity and mTORC1 signaling pathway, suggesting that these multifaceted glycolytic enzymes not only function in canonical metabolism but also directly link metabolism to epigenetic and transcription programs implicated in tumorigenesis. These findings underscore our understanding about how tumor cells adapt to nutrient and fuel availability in the environment and most importantly, provide insights into development of cancer therapy.

  11. The role of antimicrobial peptides in skin tumorigenesis

    Directory of Open Access Journals (Sweden)

    Małgorzata Marcinkiewicz

    2016-05-01

    Full Text Available Antimicrobial peptides (AMPs, known as “natural antibiotics”, are the first line of defense in humans as effector molecules of the innate immune system of the skin. They present activity against a broad spectrum of bacteria, fungi, parasites and enveloped viruses. An increasing number of studies report altered expression of AMPs in human cancers. Antimicrobial peptides such as human β defensins, human cathelicidin, ribonuclease 7 and psoriasin, a member of S100 proteins, are suggested to play a role in tumor progression and tumor suppression in pre-malignant skin lesions and malignancies. Noticeable changes in AMPs expression in skin tumorigenesis suggest a correlation between peptides and cutaneous cancers, though it is still a matter of discussion. In this article we review recent studies on the relationship between antimicrobial peptides and skin tumorigenesis.

  12. Liver biopsy

    Science.gov (United States)

    Biopsy - liver; Percutaneous biopsy ... the biopsy needle to be inserted into the liver. This is often done by using ultrasound. The ... the chance of damage to the lung or liver. The needle is removed quickly. Pressure will be ...

  13. Liver Hemangioma

    Science.gov (United States)

    ... in your liver, even if it's a benign mass. There's no evidence that an untreated liver hemangioma can lead to liver ... of Nondiscrimination Advertising Mayo Clinic is a not-for-profit organization ...

  14. Weight loss following diet-induced obesity does not alter colon tumorigenesis in the AOM mouse model.

    Science.gov (United States)

    Velázquez, Kandy T; Enos, Reilly T; Carson, Meredith S; Cranford, Taryn L; Bader, Jackie E; Chatzistamou, Ioulia; Singh, Udai P; Nagarkatti, Prakash S; Nagarkatti, Mitzi; Davis, J Mark; Carson, James A; Murphy, E Angela

    2016-10-01

    Obesity presents a significant public health concern given its association with increased cancer incidence, unfavorable prognosis, and metastasis. However, there is very little literature on the effects of weight loss, following obesity, on risk for colon cancer or liver cancer. Therefore, we sought to study whether intentional weight loss through diet manipulation was capable of mitigating colon and liver cancer in mice. We fed mice with a high-fat diet (HFD) comprised of 47% carbohydrates, 40% fat, and 13% protein for 20 wk to mimic human obesity. Subsequently, azoxymethane (AOM) was used to promote colon and liver carcinogenesis. A subset of obese mice was then switched to a low-fat diet (LFD) containing 67.5% carbohydrate, 12.2% fat, and 20% protein to promote intentional weight loss. Body weight loss and excess fat reduction did not protect mice from colon cancer progression and liver dysplastic lesion in the AOM-chemical-cancer model even though these mice had improved blood glucose and leptin levels. Intentional weight loss in AOM-treated mice actually produced histological changes that resemble dysplastic alterations in the liver and presented a higher percentage of F4/80(+)CD206(+) macrophages and activated T cells (CD4(+)CD69(+)) in the spleen and lymph nodes, respectively. In addition, the liver of AOM-treated mice exposed to a HFD during the entire period of the experiment exhibited a marked increase in proliferation and pNF-κB activation. Altogether, these data suggest that intentional weight loss following chemical-induced carcinogenesis does not affect colon tumorigenesis but may in fact negatively impact liver repair mechanisms. Copyright © 2016 the American Physiological Society.

  15. Lycopene metabolite, apo-10'-lycopenoic acid, inhibits diethylnitrosamine-initiated, high fat diet-promoted hepatic inflammation and tumorigenesis in mice.

    Science.gov (United States)

    Ip, Blanche C; Hu, Kang-Quan; Liu, Chun; Smith, Donald E; Obin, Martin S; Ausman, Lynne M; Wang, Xiang-Dong

    2013-12-01

    Obesity is associated with increased risk in hepatocellular carcinoma (HCC) development and mortality. An important disease control strategy is the prevention of obesity-related hepatic inflammation and tumorigenesis by dietary means. Here, we report that apo-10'-lycopenoic acid (APO10LA), a cleavage metabolite of lycopene at its 9',10'-double bond by carotene-9',10'-oxygenase, functions as an effective chemopreventative agent against hepatic tumorigenesis and inflammation. APO10LA treatment on human liver THLE-2 and HuH7 cells dose dependently inhibited cell growth and upregulated sirtuin 1 (SIRT1), a NAD(+)-dependent protein deacetylase that may suppress hepatic carcinogenesis. This observed SIRT1 induction was associated with decreased cyclin D1 protein, increased cyclin-dependent kinase inhibitor p21 protein expression, and induced apoptosis. APO10LA supplementation (10 mg/kg diet) for 24 weeks significantly reduced diethylnitrosamine-initiated, high fat diet (HFD)-promoted hepatic tumorigenesis (50% reduction in tumor multiplicity; 65% in volume) and lung tumor incidence (85% reduction) in C57Bl/6J mice. The chemopreventative effects of APO10LA were associated with increased hepatic SIRT1 protein and deacetylation of SIRT1 targets, as well as with decreased caspase-1 activation and SIRT1 protein cleavage. APO10LA supplementation in diet improved glucose intolerance and reduced hepatic inflammation [decreased inflammatory foci, TNFα, interleukin (IL)-6, NF-κB p65 protein expression, and STAT3 activation] in HFD-fed mice. Furthermore, APO10LA suppressed Akt activation, cyclin D1 gene, and protein expression and promoted PARP protein cleavage in transformed cells within liver tumors. Taken together, these data indicate that APO10LA can effectively inhibit HFD-promoted hepatic tumorigenesis by stimulating SIRT1 signaling while reducing hepatic inflammation.

  16. TGF-β signalling and liver disease.

    Science.gov (United States)

    Fabregat, Isabel; Moreno-Càceres, Joaquim; Sánchez, Aránzazu; Dooley, Steven; Dewidar, Bedair; Giannelli, Gianluigi; Ten Dijke, Peter

    2016-06-01

    The transforming growth factor-beta (TGF-β) family signalling pathways play essential roles in the regulation of different cellular processes, including proliferation, differentiation, migration or cell death, which are essential for the homeostasis of tissues and organs. Because of the diverse and pleiotropic TGF-β functions, deregulation of its pathways contributes to human disease. In the case of the liver, TGF-β signalling participates in all stages of disease progression, from initial liver injury through inflammation and fibrosis, to cirrhosis and cancer. TGF-β has cytostatic and apoptotic effects in hepatocytes, promoting liver differentiation during embryogenesis and physiological liver regeneration. However, high levels of TGF-β, as a consequence of chronic liver damage, result in activation of stellate cells to myofibroblasts and massive hepatocyte cell death, which contributes to the promotion of liver fibrosis and later cirrhosis. During liver tumorigenesis, TGF-β may behave as a suppressor factor at early stages; however, there is strong evidence that overactivation of TGF-β signalling might contribute to later tumour progression, once cells escape from its cytostatic effects. For these reasons, targeting the TGF-β signalling pathway is being explored to counteract liver disease progression. In this review, we aim to shed light on the state-of-the-art in the signalling pathways induced by TGF-β that are involved in different stages of liver physiology and pathology.

  17. gga-miR-375 plays a key role in tumorigenesis post subgroup J avian leukosis virus infection.

    Science.gov (United States)

    Li, Hongxin; Shang, Huiqing; Shu, Dingming; Zhang, Huanmin; Ji, Jun; Sun, Baoli; Li, Hongmei; Xie, Qingmei

    2014-01-01

    Avian leukosis is a neoplastic disease caused in part by subgroup J avian leukosis virus J (ALV-J). Micro ribonucleic acids (miRNAs) play pivotal oncogenic and tumour-suppressor roles in tumour development and progression. However, little is known about the potential role of miRNAs in avian leukosis tumours. We have found a novel tumour-suppressor miRNA, gga-miR-375, associated with avian leukosis tumorigenesis by miRNA microarray in a previous report. We have also previously studied the biological function of gga-miR-375; Overexpression of gga-miR-375 significantly inhibited DF-1 cell proliferation, and significantly reduced the expression of yes-associated protein 1 (YAP1) by repressing the activity of a luciferase reporter carrying the 3'-untranslated region of YAP1. This indicates that gga-miR-375 is frequently downregulated in avian leukosis by inhibiting cell proliferation through YAP1 oncogene targeting. Overexpression of gga-miR-375 markedly promoted serum starvation induced apoptosis, and there may be the reason why the tumour cycle is so long in the infected chickens. In vivo assays, gga-miR-375 was significantly downregulated in chicken livers 20 days after infection with ALV-J, and YAP1 was significantly upregulated 20 days after ALV-J infection (Pleukosis tumorigenesis.

  18. Liver regeneration.

    Science.gov (United States)

    Mao, Shennen A; Glorioso, Jaime M; Nyberg, Scott L

    2014-04-01

    The liver is unique in its ability to regenerate in response to injury. A number of evolutionary safeguards have allowed the liver to continue to perform its complex functions despite significant injury. Increased understanding of the regenerative process has significant benefit in the treatment of liver failure. Furthermore, understanding of liver regeneration may shed light on the development of cancer within the cirrhotic liver. This review provides an overview of the models of study currently used in liver regeneration, the molecular basis of liver regeneration, and the role of liver progenitor cells in regeneration of the liver. Specific focus is placed on clinical applications of current knowledge in liver regeneration, including small-for-size liver transplant. Furthermore, cutting-edge topics in liver regeneration, including in vivo animal models for xenogeneic human hepatocyte expansion and the use of decellularized liver matrices as a 3-dimensional scaffold for liver repopulation, are proposed. Unfortunately, despite 50 years of intense study, many gaps remain in the scientific understanding of liver regeneration.

  19. BAG-1 haplo-insufficiency impairs lung tumorigenesis

    Directory of Open Access Journals (Sweden)

    Camarero Guadalupe

    2004-11-01

    Full Text Available Abstract Background BAG-1 is a multifunctional co-chaperone of heat shock proteins (Hsc70/Hsp70 that is expressed in most cells. It interacts with Bcl-2 and Raf indicating that it might connect protein folding with other signaling pathways. Evidence that BAG-1 expression is frequently altered in human cancers, in particular in breast cancer, relative to normal cells has been put forward but the notion that overexpression of BAG-1 contributes to poor prognosis in tumorigenesis remains controversial. Methods We have evaluated the effect of BAG-1 heterozygosity in mice in a model of non-small-cell lung tumorigenesis with histological and molecular methods. We have generated mice heterozygous for BAG-1, carrying a BAG-1 null allele, that in addition express oncogenic, constitutively active C-Raf kinase (SP-C C-Raf BxB in type II pneumocytes. SP-C C-Raf BxB mice develop multifocal adenomas early in adulthood. Results We show that BAG-1 heterozygosity in mice impairs C-Raf oncogene-induced lung adenoma growth. Lung tumor initiation was reduced by half in BAG-1 heterozygous SP-C C-Raf BxB mice compared to their littermates. Tumor area was reduced by 75% in 4 month lungs of BAG-1 haploinsufficient mice compared to mice with two BAG-1 copies. Whereas BAG-1 heterozygosity did not affect the rate of cell proliferation or signaling through the mitogenic cascade in adenoma cells, it increased the rate of apoptosis. Conclusion Reduced BAG-1 expression specifically targets tumor cells to apoptosis and impairs tumorigenesis. Our data implicate BAG-1 as a key player in oncogenic transformation by Raf and identify it as a potential molecular target for cancer treatment.

  20. Cytoplasmic phospholipase A2 deletion enhances colon tumorigenesis.

    Science.gov (United States)

    Ilsley, Jillian N M; Nakanishi, Masako; Flynn, Christopher; Belinsky, Glenn S; De Guise, Sylvain; Adib, John N; Dobrowsky, Rick T; Bonventre, Joseph V; Rosenberg, Daniel W

    2005-04-01

    Cellular pools of free arachidonic acid are tightly controlled through enzymatic release of the fatty acid and subsequent utilization by downstream enzymes including the cyclooxygenases. Arachidonic acid cleavage from membrane phospholipids is accomplished by the actions of phospholipase A(2) (PLA(2)). Upon release, free arachidonic acid provides substrate for the synthesis of eicosanoids. However, under certain conditions, arachidonic acid may participate in ceramide-mediated apoptosis. Disruption of arachidonic acid homeostasis can shift the balance of cell turnover in favor of tumorigenesis, via overproduction of tumor-promoting eicosanoids or alternatively by limiting proapoptotic signals. In the following study, we evaluated the influence of genetic deletion of a key intracellular phospholipase, cytoplasmic PLA(2) (cPLA(2)), on azoxymethane-induced colon tumorigenesis. Heterozygous and null mice, upon treatment with the organotropic colon carcinogen, azoxymethane, developed a significant (P < 0.05) increase in colon tumor multiplicity (7.2-fold and 5.5-fold, respectively) relative to their wild-type littermates. This enhanced tumor sensitivity may be explained, in part, by the attenuated levels of apoptosis observed by terminal deoxynucleotidyl transferase-mediated nick end labeling staining within the colonic epithelium of heterozygous and null mice ( approximately 50% of wild type). The lower frequency of apoptotic cells corresponded with reduced ceramide levels (69% and 46% of wild-type littermates, respectively). Remarkably, increased tumorigenesis resulting from cPLA(2) deletion occurred despite a significant reduction in prostaglandin E(2) production, even in cyclooxygenase-2-overexpressing tumors. These data contribute new information that supports a fundamental role of cPLA(2) in the control of arachidonic acid homeostasis and cell turnover. Our findings indicate that the proapoptotic role of cPLA(2) in the colon may supercede its contribution to

  1. The Role of MUC1 Cytoplasmic Domain in Tumorigenesis

    Science.gov (United States)

    2005-05-01

    5 AD Award Number: DAMD17-02-1-0476 TITLE: The Role of MUCI Cytoplasmic Domain in Tumorigenesis PRINCIPAL INVESTIGATOR: Assah Al-Masri CONTRACTING ...The overall aim of the research is to develop a better understanding of the role of MUCI in breast cancer. Loss of Mucl (mouse homologue of MUC1...significant delay in tumor progression that is observed in the absence of Mucl . We suggest that the interaction of Mucl with c-Src, a key player in PyV MT

  2. Drosophila as a model for context-dependent tumorigenesis.

    Science.gov (United States)

    Tipping, Marla; Perrimon, Norbert

    2014-01-01

    Drosophila can exhibit classic hallmarks of cancer, such as evasion of apoptosis, sustained proliferation, metastasis, prolonged survival, genome instability, and metabolic reprogramming, when cancer-related genes are perturbed. In the last two decades, studies in flies have identified several tumor suppressor and oncogenes. However, the greatest strength of the fly lies in its ability to model cancer hallmarks in a variety of tissue types, which enables the study of context-dependent tumorigenesis. We review the organs and tissues that have been used to model tumor formation, and propose new strategies to maximize the potential of Drosophila in cancer research.

  3. Lycopene attenuated hepatic tumorigenesis via differential mechanisms depending on carotenoid cleavage enzyme in mice.

    Science.gov (United States)

    Ip, Blanche C; Liu, Chun; Ausman, Lynne M; von Lintig, Johannes; Wang, Xiang-Dong

    2014-12-01

    Obesity is associated with increased liver cancer risks and mortality. We recently showed that apo-10'-lycopenoic acid, a lycopene metabolite generated by beta-carotene-9',10'-oxygenase (BCO2), inhibited carcinogen-initiated, high-fat diet (HFD)-promoted liver inflammation, and hepatic tumorigenesis development. The present investigation examined the outstanding question of whether lycopene could suppress HFD-promoted hepatocellular carcinoma (HCC) progression, and if BCO2 expression is important using BCO2-knockout (BCO2-KO) and wild-type male mice. Results showed that lycopene supplementation (100 mg/kg diet) for 24 weeks resulted in comparable accumulation of hepatic lycopene (19.4 vs. 18.2 nmol/g) and had similar effects on suppressing HFD-promoted HCC incidence (19% vs. 20%) and multiplicity (58% vs. 62%) in wild-type and BCO2-KO mice, respectively. Intriguingly, lycopene chemopreventive effects in wild-type mice were associated with reduced hepatic proinflammatory signaling (phosphorylation of NK-κB p65 and STAT3; IL6 protein) and inflammatory foci. In contrast, the protective effects of lycopene in BCO2-KO but not in wild-type mice were associated with reduced hepatic endoplasmic reticulum stress-mediated unfolded protein response (ER(UPR)), through decreasing ER(UPR)-mediated protein kinase RNA-activated like kinase-eukaryotic initiation factor 2α activation, and inositol requiring 1α-X-box-binding protein 1 signaling. Lycopene supplementation in BCO2-KO mice suppressed oncogenic signals, including Met mRNA, β-catenin protein, and mTOR complex 1 activation, which was associated with increased hepatic microRNA (miR)-199a/b and miR214 levels. These results provided novel experimental evidence that dietary lycopene can prevent HFD-promoted HCC incidence and multiplicity in mice, and may elicit different mechanisms depending on BCO2 expression. ©2014 American Association for Cancer Research.

  4. Peroxiredoxin II promotes hepatic tumorigenesis through cooperation with Ras/Forkhead box M1 signaling pathway.

    Science.gov (United States)

    Park, Y-H; Kim, S-U; Kwon, T-H; Kim, J-M; Song, I-S; Shin, H-J; Lee, B-K; Bang, D-H; Lee, S-J; Lee, D-S; Chang, K-T; Kim, B-Y; Yu, D-Y

    2016-07-07

    The current study was carried out to define the involvement of Peroxiredoxin (Prx) II in progression of hepatocellular carcinoma (HCC) and the underlying molecular mechanism(s). Expression and function of Prx II in HCC was determined using H-ras(G12V)-transformed HCC cells (H-ras(G12V)-HCC cells) and the tumor livers from H-ras(G12V)-transgenic (Tg) mice and HCC patients. Prx II was upregulated in H-ras(G12V)-HCC cells and H-ras(G12V)-Tg mouse tumor livers, the expression pattern of which highly similar to that of forkhead Box M1 (FoxM1). Moreover, either knockdown of FoxM1 or site-directed mutagenesis of FoxM1-binding site of Prx II promoter significantly reduced Prx II levels in H-ras(G12V)-HCC cells, indicating FoxM1 as a direct transcription factor of Prx II in HCC. Interestingly, the null mutation of Prx II markedly decreased the number and size of tumors in H-ras(G12V)-Tg livers. Consistent with this, knockdown of Prx II in H-ras(G12V)-HCC cells reduced the expression of cyclin D1, cell proliferation, anchorage-independent growth and tumor formation in athymic nude mice, whereas overexpression of Prx II increased or aggravated the tumor phenotypes. Importantly, the expression of Prx II was correlated with that of FoxM1 in HCC patients. The activation of extracellular signal-related kinase (ERK) pathway and the expression of FoxM1 and cyclin D1 were highly dependent on Prx II in H-ras(G12V)-HCC cells and H-ras(G12V)-Tg livers. Prx II is FoxM1-dependently-expressed antioxidant in HCC and function as an enhancer of Ras(G12V) oncogenic potential in hepatic tumorigenesis through activation of ERK/FoxM1/cyclin D1 cascade.

  5. Protection against N-nitrosodiethylamine and benzo[a]pyrene-induced forestomach and lung tumorigenesis in A/J mice by green tea.

    Science.gov (United States)

    Katiyar, S K; Agarwal, R; Zaim, M T; Mukhtar, H

    1993-05-01

    In recent years we and others have shown the cancer chemopreventive effects of green tea in several animal tumor models. In this study we assessed the cancer chemopreventive effects of water extract of green tea (WEGT) and the polyphenolic fraction (GTP) isolated from WEGT against N-nitrosodiethylamine (DEN)- and benzo[a]pyrene (BP)-induced forestomach and lung tumorigenesis in A/J mice. The protective effects, both in forestomach and lungs, were evident by a decrease in number of tumors and the percentage of mice with tumors when WEGT and GTP were fed to animals during initiation, post-initiation and entire period of tumorigenesis protocols. Oral feeding of 0.2% GTP in drinking water to mice afforded 68-82 and 39-66% protection against DEN- and BP-induced forestomach tumorigenesis respectively. In case of pulmonary tumor multiplicity caused by DEN and BP, the protective effects of GTP were between 38-43 and 25-46% respectively. Similarly, oral feeding of 2.5% WEGT to mice also afforded 80-85 and 61-71% protection against DEN- and BP-induced forestomach tumorigenesis respectively. In case of lung tumorigenesis, the protective effects of WEGT were 43-62 and 25-51% respectively. Histological studies of forestomach tumors showed significantly lower squamous cell carcinoma counts in GTP- and WEGT-fed groups of mice compared to carcinogen alone treated control group of mice. When pulmonary tumors were examined histologically, no adenocarcinomas were observed in GTP- and WEGT-fed groups of mice compared to 20% mice with adenocarcinomas in carcinogen alone treated control group. Oral feeding of GTP and WEGT in drinking water also showed significant enhancement in the activities of glutathione S-transferase and NADP(H): quinone reductase in liver, small bowel, stomach and lung. The results of this study suggest that green tea possesses chemopreventive effects against carcinogen-induced tumorigenesis in internal body organs, and that the mechanism of such effects may

  6. Liver Immunology

    Science.gov (United States)

    Bogdanos, Dimitrios P.; Gao, Bin; Gershwin, M. Eric

    2014-01-01

    The liver is the largest organ in the body and is generally regarded by non-immunologists as not having lymphoid function. However, such is far from accurate. This review highlights the importance of the liver as a lymphoid organ. Firstly, we discuss experimental data surrounding the role of liver as a lymphoid organ. The liver facilitates a tolerance rather than immunoreactivity, which protects the host from antigenic overload of dietary components and drugs derived from the gut and is also instrumental to fetal immune tolerance. Loss of liver tolerance leads to autoaggressive phenomena which if are not controlled by regulatory lymphoid populations may lead to the induction of autoimmune liver diseases. Liver-related lymphoid subpopulations also act as critical antigen-presenting cells. The study of the immunological properties of liver and delineation of the microenvironment of the intrahepatic milieu in normal and diseased livers provides a platform to understand the hierarchy of a series of detrimental events which lead to immune-mediated destruction of the liver and the rejection of liver allografts. The majority of emphasis within this review will be on the normal mononuclear cell composition of the liver. However, within this context, we will discus select, but not all, immune mediated liver disease and attempt to place these data in the context of human autoimmunity. PMID:23720323

  7. New and emerging factors in tumorigenesis: an overview.

    Science.gov (United States)

    Kim, Suwon

    2015-01-01

    This article provides an overview of the genes and cellular processes that have emerged recently as new key factors in tumorigenesis. We review these in the context of three broad categories. First, genome-scale sequencing studies have revealed a set of frequently mutated genes in cancer. Genes that are mutated in >5% of all cancers across tissue types are discussed, with a highlighted focus on the two most frequently mutated genes, TP53 and PIK3CA. Second, the mechanisms of resistance to targeted therapy are reviewed. These include acquired resistance under targeted therapy selection owing to mutations and amplification of genes in the same or parallel signaling pathways. Importantly, sequencing of primary tumors has revealed that therapy-resistant clones already exist prior to targeted therapy, demonstrating that tumor heterogeneity in primary tumors confers a mechanism for inherent therapy resistance. Third, "metastasis-specific genes", or rather lack thereof, are discussed. While many genes have been shown to be capable of promoting metastasis in experimental systems, no common genetic alterations have been identified specific to metastatic lesions. Rather, the same gene mutations frequently found in primary tumors are also found prevalent in metastases, suggesting that the genes that drive tumorigenesis may also drive metastasis. In this light, an emerging view of metastatic progression is discussed. Collectively, these recent advances in cancer research have refined our knowledge on cancer etiology and progression but also present challenges that will require innovative new approaches to treat and manage cancer.

  8. Patched2 modulates tumorigenesis in patched1 heterozygous mice.

    Science.gov (United States)

    Lee, Youngsoo; Miller, Heather L; Russell, Helen R; Boyd, Kelli; Curran, Tom; McKinnon, Peter J

    2006-07-15

    The sonic hedgehog (SHH) receptor Patched 1 (Ptch1) is critical for embryonic development, and its loss is linked to tumorigenesis. Germ line inactivation of one copy of Ptch1 predisposes to basal cell carcinoma and medulloblastoma in mouse and man. In many cases, medulloblastoma arising from perturbations of Ptch1 function leads to a concomitant up-regulation of a highly similar gene, Patched2 (Ptch2). As increased expression of Ptch2 is associated with medulloblastoma and other tumors, we investigated the role of Ptch2 in tumor suppression by generating Ptch2-deficient mice. In striking contrast to Ptch1-/- mice, Ptch2-/- animals were born alive and showed no obvious defects and were not cancer prone. However, loss of Ptch2 markedly affected tumor formation in combination with Ptch1 haploinsufficiency. Ptch1+/-Ptch2-/- and Ptch1+/-Ptch2+/- animals showed a higher incidence of tumors and a broader spectrum of tumor types compared with Ptch1+/- animals. Therefore, Ptch2 modulates tumorigenesis associated with Ptch1 haploinsufficiency.

  9. Aerosol administration of phospho-sulindac inhibits lung tumorigenesis.

    Science.gov (United States)

    Cheng, Ka Wing; Wong, Chi C; Alston, Ninche; Mackenzie, Gerardo G; Huang, Liqun; Ouyang, Nengtai; Xie, Gang; Wiedmann, Timothy; Rigas, Basil

    2013-08-01

    Phospho-sulindac is a sulindac derivative with promising anticancer activity in lung cancer, but its limited metabolic stability presents a major challenge for systemic therapy. We reasoned that inhalation delivery of phospho-sulindac might overcome first-pass metabolism and produce high levels of intact drug in lung tumors. Here, we developed a system for aerosolization of phospho-sulindac and evaluated the antitumor efficacy of inhaled phospho-sulindac in an orthotopic model of human non-small cell lung cancer (A549 cells). We found that administration by inhalation delivered high levels of phospho-sulindac to the lungs and minimized its hydrolysis to less active metabolites. Consequently, inhaled phospho-sulindac (6.5 mg/kg) was highly effective in inhibiting lung tumorigenesis (75%; P sulindac suppressed lung tumorigenesis by (i) inhibiting EGF receptor (EGFR) activation, leading to profound inhibition of Raf/MEK/ERK and PI3K/AKT/mTOR survival cascades; (ii) inducing oxidative stress, which provokes the collapse of mitochondrial membrane potential and mitochondria-dependent cell death; and (iii) inducing autophagic cell death. Our data establish that inhalation delivery of phospho-sulindac is an efficacious approach to the control of lung cancer, which merits further evaluation.

  10. Liver Diseases

    Science.gov (United States)

    Your liver is the largest organ inside your body. It helps your body digest food, store energy, and remove poisons. There are many kinds of liver diseases: Diseases caused by viruses, such as hepatitis ...

  11. Fatty Liver

    Science.gov (United States)

    ... Abbreviations Weights & Measures ENGLISH View Professional English Deutsch Japanese Espaniol Find information on medical topics, symptoms, drugs, ... inside liver cells. Just consuming a high-fat diet does not result in fatty liver. Rarely, fat ...

  12. Liver disease

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/000205.htm Liver disease To use the sharing features on this page, please enable JavaScript. The term "liver disease" applies to many conditions that stop the ...

  13. Liver Disease

    Science.gov (United States)

    ... stay still. Liver disease has many causes. Infection Parasites and viruses can infect the liver, causing inflammation ... beyond. National Institute of Diabetes and Digestive and Kidney Diseases. http://digestive.niddk.nih.gov/ddiseases/pubs/ ...

  14. Lineage-dependent effects of aryl hydrocarbon receptor agonists contribute to liver tumorigenesis

    OpenAIRE

    Harrill, Joshua A.; Bethany B Parks; Wauthier, Eliane; Rowlands, J. Craig; Reid, Lola M.; Thomas, Russell S.

    2015-01-01

    Rodent cancer bioassays indicate that the aryl hydrocarbon receptor (AHR) agonist, 2,3,7,8-tetracholorodibenzo-p-dioxin (TCDD), causes increases in both hepatocytic and cholangiocytic tumors. Effects of AHR activation have been evaluated on rodent hepatic stem cells (rHpSCs) versus their descendants, hepatoblasts (rHBs), two lineage stages of multipotent, hepatic precursors with overlapping but also distinct phenotypic traits. This was made possible by defining the first successful culture co...

  15. Liver regeneration signature in hepatitis B virus (HBV-associated acute liver failure identified by gene expression profiling.

    Directory of Open Access Journals (Sweden)

    Oriel Nissim

    Full Text Available INTRODUCTION: The liver has inherent regenerative capacity via mitotic division of mature hepatocytes or, when the hepatic loss is massive or hepatocyte proliferation is impaired, through activation of hepatic stem/progenitor cells (HSPC. The dramatic clinical course of acute liver failure (ALF has posed major limitations to investigating the molecular mechanisms of liver regeneration and the role of HSPC in this setting. We investigated the molecular mechanisms of liver regeneration in 4 patients who underwent liver transplantation for hepatitis B virus (HBV-associated ALF. METHODS AND FINDINGS: Gene expression profiling of 17 liver specimens from the 4 ALF cases and individual specimens from 10 liver donors documented a distinct gene signature for ALF. However, unsupervised multidimensional scaling and hierarchical clustering identified two clusters of ALF that segregated according to histopathological severity massive hepatic necrosis (MHN; 2 patients and submassive hepatic necrosis (SHN; 2 patients. We found that ALF is characterized by a strong HSPC gene signature, along with ductular reaction, both of which are more prominent in MHN. Interestingly, no evidence of further lineage differentiation was seen in MHN, whereas in SHN we detected cells with hepatocyte-like morphology. Strikingly, ALF was associated with a strong tumorigenesis gene signature. MHN had the greatest upregulation of stem cell genes (EpCAM, CK19, CK7, whereas the most up-regulated genes in SHN were related to cellular growth and proliferation. The extent of liver necrosis correlated with an overriding fibrogenesis gene signature, reflecting the wound-healing process. CONCLUSION: Our data provide evidence for a distinct gene signature in HBV-associated ALF whose intensity is directly correlated with the histopathological severity. HSPC activation and fibrogenesis positively correlated with the extent of liver necrosis. Moreover, we detected a tumorigenesis gene signature

  16. Telomere Replication Stress Induced by POT1 Inactivation Accelerates Tumorigenesis.

    Science.gov (United States)

    Pinzaru, Alexandra M; Hom, Robert A; Beal, Angela; Phillips, Aaron F; Ni, Eric; Cardozo, Timothy; Nair, Nidhi; Choi, Jaehyuk; Wuttke, Deborah S; Sfeir, Agnel; Denchi, Eros Lazzerini

    2016-06-01

    Genome sequencing studies have revealed a number of cancer-associated mutations in the telomere-binding factor POT1. Here, we show that when combined with p53 deficiency, depletion of murine POT1a in common lymphoid progenitor cells fosters genetic instability, accelerates the onset, and increases the severity of T cell lymphomas. In parallel, we examined human and mouse cells carrying POT1 mutations found in cutaneous T cell lymphoma (CTCL) patients. Inhibition of POT1 activates ATR-dependent DNA damage signaling and induces telomere fragility, replication fork stalling, and telomere elongation. Our data suggest that these phenotypes are linked to impaired CST (CTC1-STN1-TEN1) function at telomeres. Lastly, we show that proliferation of cancer cells lacking POT1 is enabled by the attenuation of the ATR kinase pathway. These results uncover a role for defective telomere replication during tumorigenesis.

  17. Telomere Replication Stress Induced by POT1 Inactivation Accelerates Tumorigenesis

    Directory of Open Access Journals (Sweden)

    Alexandra M. Pinzaru

    2016-06-01

    Full Text Available Genome sequencing studies have revealed a number of cancer-associated mutations in the telomere-binding factor POT1. Here, we show that when combined with p53 deficiency, depletion of murine POT1a in common lymphoid progenitor cells fosters genetic instability, accelerates the onset, and increases the severity of T cell lymphomas. In parallel, we examined human and mouse cells carrying POT1 mutations found in cutaneous T cell lymphoma (CTCL patients. Inhibition of POT1 activates ATR-dependent DNA damage signaling and induces telomere fragility, replication fork stalling, and telomere elongation. Our data suggest that these phenotypes are linked to impaired CST (CTC1-STN1-TEN1 function at telomeres. Lastly, we show that proliferation of cancer cells lacking POT1 is enabled by the attenuation of the ATR kinase pathway. These results uncover a role for defective telomere replication during tumorigenesis.

  18. Wnt signaling and colon tumorigenesis - A view from the periphery

    Energy Technology Data Exchange (ETDEWEB)

    Burgess, Antony W., E-mail: burgess@ludwig.edu.au [Parkville Branch, Ludwig Institute for Cancer Research, Melbourne, 3050 (Australia); Faux, Maree C. [Parkville Branch, Ludwig Institute for Cancer Research, Melbourne, 3050 (Australia); Layton, Meredith J. [Department of Biochemistry and Molecular Biology, Monash University, Melbourne, 3800 (Australia); Ramsay, Robert G. [Peter MacCallum Cancer Centre, Melbourne, 3002 (Australia); Pathology Department, the University of Melbourne, Parkville, 3050 (Australia)

    2011-11-15

    In this brief overview we discuss the association between Wnt signaling and colon cell biology and tumorigenesis. Our current understanding of the role of Apc in the {beta}-catenin destruction complex is compared with potential roles for Apc in cell adhesion and migration. The requirement for phosphorylation in the proteasomal-mediated degradation of {beta}-catenin is contrasted with roles for phospho-{beta}-catenin in the activation of transcription, cell adhesion and migration. The synergy between Myb and {beta}-catenin regulation of transcription in crypt stem cells during Wnt signaling is discussed. Finally, potential effects of growth factor regulatory systems, Apc or truncated-Apc on crypt morphogenesis, stem cell localization and crypt fission are considered.

  19. ATM promotes apoptosis and suppresses tumorigenesis in response to Myc

    Science.gov (United States)

    Pusapati, Raju V.; Rounbehler, Robert J.; Hong, Sungki; Powers, John T.; Yan, Mingshan; Kiguchi, Kaoru; McArthur, Mark J.; Wong, Paul K.; Johnson, David G.

    2006-01-01

    Overexpression of the c-myc oncogene contributes to the development of a significant number of human cancers. In response to deregulated Myc activity, the p53 tumor suppressor is activated to promote apoptosis and inhibit tumor formation. Here we demonstrate that p53 induction in response to Myc overexpression requires the ataxia-telangiectasia mutated (ATM) kinase, a major regulator of the cellular response to DNA double-strand breaks. In a transgenic mouse model overexpressing Myc in squamous epithelial tissues, inactivation of Atm suppresses apoptosis and accelerates tumorigenesis. Deregulated Myc expression induces DNA damage in primary transgenic keratinocytes and the formation of H2AX and phospho-SMC1 foci in transgenic tissue. These findings suggest that Myc overexpression causes DNA damage in vivo and that the ATM-dependent response to this damage is critical for p53 activation, apoptosis, and the suppression of tumor development. p53 | DNA damage

  20. Role of Dicer on tumorigenesis in glioma cells

    Institute of Scientific and Technical Information of China (English)

    Anling Zhang; Lei Han; Guangxiu Wang; Zhifan Jia; Peiyu Pu; Chunsheng Kang

    2010-01-01

    Micro RNAs(miRNAs)are non-coding,single-stranded RNAs that regulate target gene expression by repressing translation or promoting RNA cleavage.Recent studies show that miRNA expression is globally decreased in some human tumors.Dicer is an essential component of the miRNA processing machinery.To determine whether global reduction of miRNA effects tumorigenesis,small interfering RNA were designed to target Dicer to restrain whole miRNA expression in the glioblastoma cell line-TJ905.With effective knock-down of Dicer,tumor cells were invasive and proliferative,and globally impaired miRNA processing enhanced proliferation and invasiveness of glioma cells in vitro.Suppression of Dicer expression resulted in a more aggressive glioma phenotype,which suggests that global reduction of miRNA expression could have an oncogenic role in glioblastoma cells.

  1. Expression and methylation pattern of p16 in neuroblastoma tumorigenesis.

    Science.gov (United States)

    Aktas, Safiye; Celebiler, Aydan Cavusoglu; Zadeoğlulari, Zeynep; Diniz, Gulden; Kargi, Aydanur; Olgun, Nur

    2010-03-01

    Understanding migration, population and differentiation of primordial neural crest cells will help in evolving biology of neuroblastoma. P16 is a tumour suppressor gene contributing in cell cycle arrest as cyclin dependent kinase inhibitor. Methylation is an important mechanism for silencing tumor suppressor genes. The aim of this study was to evaluate the role of p16 and its methylation pattern in neuroblastoma tumorigenesis. This study included 23 cases (11 male; 12 female) and 31 samples from archival paraffin embedded tissues. P16 was studied in 5 samples of normal adrenal medullar tissue, 5 samples of adrenal tissue including blastic rests, 5 samples of neuroblastoma in situ tissue and in 8 samples of neuroblastoma tissues primary and after chemotherapy in each group. The adrenal gland tissues were obtained from paediatric autopsy cases. Expression of p16 was searched by immunohistochemistry. Methylation specific PCR was used to detect the methylation rate of p16. The age range of autopsy cases was between 20 weeks of foetal age and 36 months of infant age. The mean age of neuroblastoma cases was 45 months. P16 expression was positive in normal adrenal tissues, in one of 5 samples of adrenal blastic rest tissue and in all of samples of after chemotherapy; while no expression was observed in neuroblastoma and neuroblastoma in situ tissues. P16 methylation was observed in samples of neuroblastoma in situ and primary neuroblastoma tissues. Our results suggest that p16 and its methylation seems to play role in neuroblastoma tumorigenesis and in the migration, population and differentiation of primordial neural crest cells. Inhibitors of DNA methylation may provide a useful tool for restoring p16 activity in neuroblastoma treatment.

  2. New and emerging factors in tumorigenesis: an overview

    Directory of Open Access Journals (Sweden)

    Kim S

    2015-07-01

    Full Text Available Suwon Kim1,2 1Department of Basic Medical Sciences, University of Arizona College of Medicine-Phoenix, 2Cancer and Cell Biology Division, Translational Genomics Research Institute, Phoenix, AZ, USA Abstract: This article provides an overview of the genes and cellular processes that have emerged recently as new key factors in tumorigenesis. We review these in the context of three broad categories. First, genome-scale sequencing studies have revealed a set of frequently mutated genes in cancer. Genes that are mutated in >5% of all cancers across tissue types are discussed, with a highlighted focus on the two most frequently mutated genes, TP53 and PIK3CA. Second, the mechanisms of resistance to targeted therapy are reviewed. These include acquired resistance under targeted therapy selection owing to mutations and amplification of genes in the same or parallel signaling pathways. Importantly, sequencing of primary tumors has revealed that therapy-resistant clones already exist prior to targeted therapy, demonstrating that tumor heterogeneity in primary tumors confers a mechanism for inherent therapy resistance. Third, “metastasis-specific genes”, or rather lack thereof, are discussed. While many genes have been shown to be capable of promoting metastasis in experimental systems, no common genetic alterations have been identified specific to metastatic lesions. Rather, the same gene mutations frequently found in primary tumors are also found prevalent in metastases, suggesting that the genes that drive tumorigenesis may also drive metastasis. In this light, an emerging view of metastatic progression is discussed. Collectively, these recent advances in cancer research have refined our knowledge on cancer etiology and progression but also present challenges that will require innovative new approaches to treat and manage cancer. Keywords: cancer, genomics, gene mutations, targeted therapy resistance, tumor heterogeneity, metastasis

  3. Benign Liver Tumors

    Science.gov (United States)

    ... A Life After Diagnosis Support for Chronic Illness Corporate Partnerships Interview with Kristen Hanks Liver Lowdown July ... Disease , Liver Transplant , Liver Cancer , Liver Tumor , Liver Failure Help Fight Liver Disease We rely upon donations ...

  4. What Is Liver Cancer?

    Science.gov (United States)

    ... Research? Liver Cancer About Liver Cancer What Is Liver Cancer? Cancer starts when cells in the body ... structure and function of the liver. About the liver The liver is the largest internal organ. It ...

  5. Liver Transplant

    Science.gov (United States)

    ... Liver Disease & NASH Definition & Facts Symptoms & Causes Diagnosis Treatment Eating, Diet, & Nutrition Clinical Trials Biliary Atresia Cirrhosis Hemochromatosis Hepatitis A through E (Viral Hepatitis) Hepatitis ...

  6. Liver anatomy.

    Science.gov (United States)

    Abdel-Misih, Sherif R Z; Bloomston, Mark

    2010-08-01

    Understanding the complexities of the liver has been a long-standing challenge to physicians and anatomists. Significant strides in the understanding of hepatic anatomy have facilitated major progress in liver-directed therapies--surgical interventions, such as transplantation, hepatic resection, hepatic artery infusion pumps, and hepatic ablation, and interventional radiologic procedures, such as transarterial chemoembolization, selective internal radiation therapy, and portal vein embolization. Without understanding hepatic anatomy, such progressive interventions would not be feasible. This article reviews the history, general anatomy, and the classification schemes of liver anatomy and their relevance to liver-directed therapies. Copyright 2010 Elsevier Inc. All rights reserved.

  7. Berberine regulates AMP-activated protein kinase signaling pathways and inhibits colon tumorigenesis in mice.

    Science.gov (United States)

    Li, Weidong; Hua, Baojin; Saud, Shakir M; Lin, Hongsheng; Hou, Wei; Matter, Matthias S; Jia, Libin; Colburn, Nancy H; Young, Matthew R

    2015-10-01

    Colorectal cancer, a leading cause of cancer death, has been linked to inflammation and obesity. Berberine, an isoquinoline alkaloid, possesses anti-inflammatory, anti-diabetes and anti-tumor properties. In the azoxymethane initiated and dextran sulfate sodium (AOM/DSS) promoted colorectal carcinogenesis mouse model, berberine treated mice showed a 60% reduction in tumor number (P = 0.009), a 48% reduction in tumors 4 mm (P = 0.02) compared to vehicle treated mice. Berberine also decreased AOM/DSS induced Ki-67 and COX-2 expression. In vitro analysis showed that in addition to its anti-proliferation activity, berberine also induced apoptosis in colorectal cancer cell lines. Berberine activated AMP-activated protein kinase (AMPK), a major regulator of metabolic pathways, and inhibited mammalian target of rapamycin (mTOR), a downstream target of AMPK. Furthermore, 4E-binding protein-1 and p70 ribosomal S6 kinases, downstream targets of mTOR, were down regulated by berberine treatment. Berberine did not affect Liver kinase B1 (LKB1) activity or the mitogen-activated protein kinase pathway. Berberine inhibited Nuclear Factor kappa-B (NF-κB) activity, reduced the expression of cyclin D1 and survivin, induced phosphorylation of p53 and increased caspase-3 cleavage in vitro. Berberine inhibition of mTOR activity and p53 phosphorylation was found to be AMPK dependent, while inhibition NF-κB was AMPK independent. In vivo, berberine also activated AMPK, inhibited mTOR and p65 phosphorylation and activated caspase-3 cleavage. Our data suggests that berberine suppresses colon epithelial proliferation and tumorigenesis via AMPK dependent inhibition of mTOR activity and AMPK independent inhibition of NF-κB.

  8. gga-miR-375 plays a key role in tumorigenesis post subgroup J avian leukosis virus infection.

    Directory of Open Access Journals (Sweden)

    Hongxin Li

    Full Text Available Avian leukosis is a neoplastic disease caused in part by subgroup J avian leukosis virus J (ALV-J. Micro ribonucleic acids (miRNAs play pivotal oncogenic and tumour-suppressor roles in tumour development and progression. However, little is known about the potential role of miRNAs in avian leukosis tumours. We have found a novel tumour-suppressor miRNA, gga-miR-375, associated with avian leukosis tumorigenesis by miRNA microarray in a previous report. We have also previously studied the biological function of gga-miR-375; Overexpression of gga-miR-375 significantly inhibited DF-1 cell proliferation, and significantly reduced the expression of yes-associated protein 1 (YAP1 by repressing the activity of a luciferase reporter carrying the 3'-untranslated region of YAP1. This indicates that gga-miR-375 is frequently downregulated in avian leukosis by inhibiting cell proliferation through YAP1 oncogene targeting. Overexpression of gga-miR-375 markedly promoted serum starvation induced apoptosis, and there may be the reason why the tumour cycle is so long in the infected chickens. In vivo assays, gga-miR-375 was significantly downregulated in chicken livers 20 days after infection with ALV-J, and YAP1 was significantly upregulated 20 days after ALV-J infection (P<0.05. We also found that expression of cyclin E, an important regulator of cell cycle progression, was significantly upregulated (P<0.05. Drosophila inhibitor of apoptosis protein 1 (DIAP1, which is related to caspase-dependent apoptosis, was also significantly upregulated after infection. Our data suggests that gga-miR-375 may function as a tumour suppressor thereby regulating cancer cell proliferation and it plays a key role in avian leukosis tumorigenesis.

  9. Harderian Gland Tumorigenesis: Low-Dose and LET Response

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Polly Y. [SRI International, Menlo Park, CA (United States). Biosciences Div.; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Life Sciences Div.; Cucinotta, Francis A. [Univ. of Nevada, Las Vegas, NV (United States). Dept. of Health Physics and Diagnostic Sciences; Bjornstad, Kathleen A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Life Sciences Div.; Bakke, James [SRI International, Menlo Park, CA (United States). Biosciences Div.; Rosen, Chris J. [SRI International, Menlo Park, CA (United States). Biosciences Div.; Du, Nicholas [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Life Sciences Div.; Fairchild, David G. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Life Sciences Div.; Cacao, Eliedonna [Univ. of Nevada, Las Vegas, NV (United States). Dept. of Health Physics and Diagnostic Sciences; Blakely, Eleanor A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Life Sciences Div.

    2016-04-19

    Increased cancer risk remains a primary concern for travel into deep space and may preclude manned missions to Mars due to large uncertainties that currently exist in estimating cancer risk from the spectrum of radiations found in space with the very limited available human epidemiological radiation-induced cancer data. Existing data on human risk of cancer from X-ray and gamma-ray exposure must be scaled to the many types and fluences of radiations found in space using radiation quality factors and dose-rate modification factors, and assuming linearity of response since the shapes of the dose responses at low doses below 100 mSv are unknown. The goal of this work was to reduce uncertainties in the relative biological effect (RBE) and linear energy transfer (LET) relationship for space-relevant doses of charged-particle radiation-induced carcinogenesis. The historical data from the studies of Fry et al. and Alpen et al. for Harderian gland (HG) tumors in the female CB6F1 strain of mouse represent the most complete set of experimental observations, including dose dependence, available on a specific radiation-induced tumor in an experimental animal using heavy ion beams that are found in the cosmic radiation spectrum. However, these data lack complete information on low-dose responses below 0.1 Gy, and for chronic low-dose-rate exposures, and there are gaps in the LET region between 25 and 190 keV/μm. In this study, we used the historical HG tumorigenesis data as reference, and obtained HG tumor data for 260 MeV/u silicon (LET ~70 keV/μm) and 1,000 MeV/u titanium (LET ~100 keV/μm) to fill existing gaps of data in this LET range to improve our understanding of the dose-response curve at low doses, to test for deviations from linearity and to provide RBE estimates. Animals were also exposed to five daily fractions of 0.026 or 0.052 Gy of 1,000 MeV/u titanium ions to simulate chronic exposure, and HG tumorigenesis from this fractionated study were compared to the

  10. Harderian Gland Tumorigenesis: Low-Dose and LET Response.

    Science.gov (United States)

    Chang, Polly Y; Cucinotta, Francis A; Bjornstad, Kathleen A; Bakke, James; Rosen, Chris J; Du, Nicholas; Fairchild, David G; Cacao, Eliedonna; Blakely, Eleanor A

    2016-05-01

    Increased cancer risk remains a primary concern for travel into deep space and may preclude manned missions to Mars due to large uncertainties that currently exist in estimating cancer risk from the spectrum of radiations found in space with the very limited available human epidemiological radiation-induced cancer data. Existing data on human risk of cancer from X-ray and gamma-ray exposure must be scaled to the many types and fluences of radiations found in space using radiation quality factors and dose-rate modification factors, and assuming linearity of response since the shapes of the dose responses at low doses below 100 mSv are unknown. The goal of this work was to reduce uncertainties in the relative biological effect (RBE) and linear energy transfer (LET) relationship for space-relevant doses of charged-particle radiation-induced carcinogenesis. The historical data from the studies of Fry et al. and Alpen et al. for Harderian gland (HG) tumors in the female CB6F1 strain of mouse represent the most complete set of experimental observations, including dose dependence, available on a specific radiation-induced tumor in an experimental animal using heavy ion beams that are found in the cosmic radiation spectrum. However, these data lack complete information on low-dose responses below 0.1 Gy, and for chronic low-dose-rate exposures, and there are gaps in the LET region between 25 and 190 keV/μm. In this study, we used the historical HG tumorigenesis data as reference, and obtained HG tumor data for 260 MeV/u silicon (LET ∼70 keV/μm) and 1,000 MeV/u titanium (LET ∼100 keV/μm) to fill existing gaps of data in this LET range to improve our understanding of the dose-response curve at low doses, to test for deviations from linearity and to provide RBE estimates. Animals were also exposed to five daily fractions of 0.026 or 0.052 Gy of 1,000 MeV/u titanium ions to simulate chronic exposure, and HG tumorigenesis from this fractionated study were compared to the

  11. Liver spots

    Science.gov (United States)

    Liver spots are changes in skin color that occur in older skin. The coloring may be due to aging, exposure to the sun or other sources of ultraviolet light, or causes that are not known. Liver spots are very common after age 40. They occur ...

  12. Luminal Iron Levels Govern Intestinal Tumorigenesis after Apc Loss In Vivo

    Directory of Open Access Journals (Sweden)

    Sorina Radulescu

    2012-08-01

    Full Text Available It is clear from epidemiological studies that excess iron is associated with increased risk of colorectal cancer; however, questions regarding the mechanism of how iron increases cancer risk, the source of the excess iron (circulating or luminal, and whether iron reduction represents a potential therapeutic option remain unanswered. In this study, we show that after Apc deletion, the cellular iron acquisition proteins TfR1 and DMT1 are rapidly induced. Conversely, restoration of APC reduces cellular iron due to repression of these proteins. To test the functional importance of these findings, we performed in vivo investigations of the impact of iron levels on intestinal tumorigenesis. Strikingly, depletion of luminal (but not systemic iron strongly suppressed murine intestinal tumorigenesis, whereas increased luminal iron strongly promoted tumorigenesis. Taken together, our data definitively delineate iron as a potent modifier of intestinal tumorigenesis and have important implications for dietary iron supplementation in patients at high risk of colorectal cancer.

  13. Stem-Like Cells in Bone Sarcomas: Implications for Tumorigenesis

    Directory of Open Access Journals (Sweden)

    C. Parker Gibbs

    2005-11-01

    Full Text Available Bone sarcomas are a clinically and molecularly heterogeneous group of malignancies characterized by varying degrees of mesenchymal differentiation. Despite advances in medical and surgical management, survival rates for high-grade tumors have remained static at 50% to 70%. Tumor stem cells have been recently implicated in the pathogenesis of other heterogeneous, highly malignant tumors. We demonstrate here the existence of a small subpopulation of self-renewing bone sarcoma cells that are capable of forming suspended spherical, clonal colonies, also called “sarcospheres,” in anchorage-independent, serum-starved conditions. These bone sarcoma cells as well as tissue specimens express activated STAT3 and the marker genes of pluripotent embryonic stem (ES cells, Oct 3/4 and Nanog. Expression levels of Oct 3/4 and Nanog are greater in sarcospheres than in adherent cultures. A subset of bone sarcoma cells displays several surface markers of mesenchymal stem cells (Stro-1, CD105, and CD44 as well as attributes of mesodermal, ectodermal, and endodermal differentiation. Although previously documented in brain and breast tumors, our results support the extension of the cancer stem cell hypothesis to include tumors of mesenchymal lineage. Furthermore, they suggest the participation of ES cell homeobox proteins in non-germ cell tumorigenesis.

  14. MicroRNA-429 Modulates Hepatocellular Carcinoma Prognosis and Tumorigenesis

    Directory of Open Access Journals (Sweden)

    Xiao-Ying Huang

    2013-01-01

    Full Text Available MicroRNA-429 (miR-429 may modify the development and progression of cancers; however, the role of this microRNA in the hepatocellular carcinoma (HCC has not been well elaborated. Here, we tested miR-429 expression in 138 pathology-diagnosed HCC cases and SMMC-7721 cells. We found that miR-429 was upregulated in HCC tumor tissues and that the high expression of miR-429 was significantly correlated with larger tumor size (odd ratio (OR, 2.70; 95% confidence interval (CI, 1.28–5.56 and higher aflatoxin B1-DNA adducts (OR = 3.13, 95% CI = 1.47–6.67. Furthermore, this microRNA overexpression modified the recurrence-free survival and overall survival of HCC patients. Functionally, miR-429 overexpression progressed tumor cells proliferation and inhibited cell apoptosis. These results indicate for the first time that miR-429 may modify HCC prognosis and tumorigenesis and may be a potential tumor therapeutic target.

  15. Luteinizing hormone promotes gonadal tumorigenesis in inhibin-deficient mice

    Science.gov (United States)

    Nagaraja, Ankur K.; Agno, Julio E.; Kumar, T. Rajendra; Matzuk, Martin M.

    2009-01-01

    Summary The inhibins are secreted α:β heterodimers of the TGF-β superfamily that are mainly synthesized in Sertoli cells and granulosa cells, and are critical regulators of testicular and ovarian development and function. Mice homozygous for a targeted deletion of the inhibin α subunit gene (Inha-/-) develop sex cord-stromal tumors in a gonadotropin-dependent manner. Here, we determine the contribution of LH to gonadal tumorigenesis by generating mice deficient in both inhibins and LH. Inha-/-Lhb-/- mice have increased survival and delayed tumor progression, and these observations correlate with lower serum FSH and estradiol levels compared to Inha-/- controls. Double mutant testicular tumors demonstrate decreased expression of cyclin D2, while double mutant ovarian tumors have elevated expression of p15INK4b and trend toward higher levels of p27Kip1. We conclude that LH is not required for tumor formation in the absence of inhibins but promotes tumor progression, likely through alterations in serum hormone levels and cell cycle regulators. PMID:18657590

  16. Molecular genetics of cancer and tumorigenesis: Drosophila models

    Institute of Scientific and Technical Information of China (English)

    Wu-Min Deng

    2011-01-01

    Why do some cells not respond to normal control of cell division and become tumorous? Which signals trigger some tumor cells to migrate and colonize other tissues? What genetic factors are responsible for tumorigenesis and cancer development? What environmental factors play a role in cancer formation and progression? In how many ways can our bodies prevent and restrict the growth of cancerous cells?How can we identify and deliver effective drugs to fight cancer? In the fight against cancer,which kills more people than any other disease,these and other questions have long interested researchers from a diverse range of fields.To answer these questions and to fight cancer more effectively,we must increase our understanding of basic cancer biology.Model organisms,including the fruit fly Drosophila melanogaster,have played instrumental roles in our understanding of this devastating disease and the search for effective cures.Drosophila and its highly effective,easy-touse,and ever-expanding genetic tools have contributed toand enriched our knowledge of cancer and tumor formation tremendously.

  17. The Functional Analysis of Histone Acetyltransferase MOF in Tumorigenesis.

    Science.gov (United States)

    Su, Jiaming; Wang, Fei; Cai, Yong; Jin, Jingji

    2016-01-14

    Changes in chromatin structure and heritably regulating the gene expression by epigenetic mechanisms, such as histone post-translational modification, are involved in most cellular biological processes. Thus, abnormal regulation of epigenetics is implicated in the occurrence of various diseases, including cancer. Human MOF (males absent on the first) is a member of the MYST (Moz-Ybf2/Sas3-Sas2-Tip60) family of histone acetyltransferases (HATs). As a catalytic subunit, MOF can form at least two distinct multiprotein complexes (MSL and NSL) in human cells. Both complexes can acetylate histone H4 at lysine 16 (H4K16); however, the NSL complex possesses broader substrate specificity and can also acetylate histone H4 at lysines 5 and 8 (H4K5 and H4K8), suggesting the complexity of the intracellular functions of MOF. Silencing of MOF in cells leads to genomic instability, inactivation of gene transcription, defective DNA damage repair and early embryonic lethality. Unbalanced MOF expression and its corresponding acetylation of H4K16 have been found in certain primary cancer tissues, including breast cancer, medulloblastoma, ovarian cancer, renal cell carcinoma, colorectal carcinoma, gastric cancer, as well as non-small cell lung cancer. In this review, we provide a brief overview of MOF and its corresponding histone acetylation, introduce recent research findings that link MOF functions to tumorigenesis and speculate on the potential role that may be relevant to tumorigenic pathways.

  18. The Functional Analysis of Histone Acetyltransferase MOF in Tumorigenesis

    Directory of Open Access Journals (Sweden)

    Jiaming Su

    2016-01-01

    Full Text Available Changes in chromatin structure and heritably regulating the gene expression by epigenetic mechanisms, such as histone post-translational modification, are involved in most cellular biological processes. Thus, abnormal regulation of epigenetics is implicated in the occurrence of various diseases, including cancer. Human MOF (males absent on the first is a member of the MYST (Moz-Ybf2/Sas3-Sas2-Tip60 family of histone acetyltransferases (HATs. As a catalytic subunit, MOF can form at least two distinct multiprotein complexes (MSL and NSL in human cells. Both complexes can acetylate histone H4 at lysine 16 (H4K16; however, the NSL complex possesses broader substrate specificity and can also acetylate histone H4 at lysines 5 and 8 (H4K5 and H4K8, suggesting the complexity of the intracellular functions of MOF. Silencing of MOF in cells leads to genomic instability, inactivation of gene transcription, defective DNA damage repair and early embryonic lethality. Unbalanced MOF expression and its corresponding acetylation of H4K16 have been found in certain primary cancer tissues, including breast cancer, medulloblastoma, ovarian cancer, renal cell carcinoma, colorectal carcinoma, gastric cancer, as well as non-small cell lung cancer. In this review, we provide a brief overview of MOF and its corresponding histone acetylation, introduce recent research findings that link MOF functions to tumorigenesis and speculate on the potential role that may be relevant to tumorigenic pathways.

  19. Alternative RNA Structure-Coupled Gene Regulations in Tumorigenesis

    Directory of Open Access Journals (Sweden)

    Feng-Chi Chen

    2014-12-01

    Full Text Available Alternative RNA structures (ARSs, or alternative transcript isoforms, are critical for regulating cellular phenotypes in humans. In addition to generating functionally diverse protein isoforms from a single gene, ARS can alter the sequence contents of 5'/3' untranslated regions (UTRs and intronic regions, thus also affecting the regulatory effects of these regions. ARS may introduce premature stop codon(s into a transcript, and render the transcript susceptible to nonsense-mediated decay, which in turn can influence the overall gene expression level. Meanwhile, ARS can regulate the presence/absence of upstream open reading frames and microRNA targeting sites in 5'UTRs and 3'UTRs, respectively, thus affecting translational efficiencies and protein expression levels. Furthermore, since ARS may alter exon-intron structures, it can influence the biogenesis of intronic microRNAs and indirectly affect the expression of the target genes of these microRNAs. The connections between ARS and multiple regulatory mechanisms underline the importance of ARS in determining cell fate. Accumulating evidence indicates that ARS-coupled regulations play important roles in tumorigenesis. Here I will review our current knowledge in this field, and discuss potential future directions.

  20. Intricacies of hedgehog signaling pathways: A perspective in tumorigenesis

    Energy Technology Data Exchange (ETDEWEB)

    Kar, Swayamsiddha; Deb, Moonmoon; Sengupta, Dipta; Shilpi, Arunima; Bhutia, Sujit Kumar [Epigenetics and Cancer Research Laboratory, Biochemistry and Molecular Biology Group, Department of Life Science, National Institute of Technology, Rourkela, Odisha 769008 (India); Patra, Samir Kumar, E-mail: samirp@nitrkl.ac.in [Epigenetics and Cancer Research Laboratory, Biochemistry and Molecular Biology Group, Department of Life Science, National Institute of Technology, Rourkela, Odisha 769008 (India)

    2012-10-01

    The hedgehog (HH) signaling pathway is a crucial negotiator of developmental proceedings in the embryo governing a diverse array of processes including cell proliferation, differentiation, and tissue patterning. The overall activity of the pathway is significantly curtailed after embryogenesis as well as in adults, yet it retains many of its functional capacities. However, aberration in HH signaling mediates the initiation, proliferation and continued sustenance of malignancy in different tissues to varying degrees through different mechanisms. In this review, we provide an overview of the role of constitutively active aberrant HH signaling pathway in different types of human cancer and the underlying molecular and genetic mechanisms that drive tumorigenesis in that particular tissue. An insight into the various modes of anomalous HH signaling in different organs will provide a comprehensive knowledge of the pathway in these tissues and open a window for individually tailored, tissue-specific therapeutic interventions. The synergistic cross talking of HH pathway with many other regulatory molecules and developmentally inclined signaling pathways may offer many avenues for pharmacological advances. Understanding the molecular basis of abnormal HH signaling in cancer will provide an opportunity to inhibit the deregulated pathway in many aggressive and therapeutically challenging cancers where promising options are not available.

  1. Dynamics of notch expression during murine prostate development and tumorigenesis.

    Science.gov (United States)

    Shou, J; Ross, S; Koeppen, H; de Sauvage, F J; Gao, W Q

    2001-10-01

    Notch signaling has been widely demonstrated to be responsible for cell fate determination during normal development and implicated in human T-cell leukemia and mouse mammary carcinomas. Here we show that Notch signaling may be involved in prostatic development and cancer cell growth. In situ hybridization and reverse transcription-PCR analyses revealed that Notch1 was expressed in prostate epithelial cells during normal development and in prostate cancer cells. Characterization of Notch1-green fluorescent protein transgenic mice, in which the expression of reporter green fluorescent protein is under the control of the Notch1 promoter, indicated that Notch1-expressing cells were associated with the basal epithelial cell population in the prostate. Examination of the transgenic adenocarcinoma of the mouse prostate showed that expression of Notch1 was elevated in malignant prostatic epithelial cells of primary and metastatic tumors. Expression of Notch ligands, however, was low or undetectable in cultured prostate cancer cells or in malignant prostatic epithelial cells in transgenic adenocarcinoma of the mouse prostate. Furthermore, overexpression of a constitutively active form of Notch1 inhibited the proliferation of various prostate cancer cells, including DU145, LNCaP, and PC3 cells. Taken together, our data indicate for the first time that Notch signaling may play a role in murine prostatic development and tumorigenesis.

  2. Survival and tumorigenesis in O6-methylguanine DNA methyltransferase-deficient mice following cyclophosphamide exposure

    OpenAIRE

    Nagasubramanian, Ramamoorthy; Hansen, Ryan J.; Delaney, Shannon M.; Cherian, Mathew M.; Samson, Leona D.; Kogan, Scott C.; Dolan, M Eileen

    2008-01-01

    O6-methylguanine DNA methyltransferase (MGMT) deficiency is associated with an increased susceptibility to alkylating agent toxicity. To understand the contribution of MGMT in protecting against cyclophosphamide (CP)-induced toxicity, mutagenesis and tumorigenesis, we compared the biological effects of this agent in transgenic Mgmt knockout and wild-type mice. In addition, neurofibromin (Nf1)+/− background was used to increase the likelihood of CP-induced tumorigenesis. Cohorts of Mgmt-profic...

  3. Overexpression of Id1 in transgenic mice promotes mammary basal stem cell activity and breast tumorigenesis

    OpenAIRE

    Shin, Dong-Hui; Park, Ji-Hye; Lee, Jeong-Yeon; Won, Hee-Young; Jang, Ki-Seok; MIN, KYUENG-WHAN; Jang, Si-Hyong; Woo, Jong-Kyu; Oh, Seung Hyun; Kong, Gu

    2015-01-01

    Inhibitor of differentiation/DNA binding (Id)1 is a crucial regulator of mammary development and breast cancer progression. However, its effect on stemness and tumorigenesis in mammary epithelial cells remains undefined. Herein, we demonstrate that Id1 induces mammary tumorigenesis by increasing normal and malignant mammary stem cell (MaSC) activities in transgenic mice. MaSC-enriched basal cell expansion and increased self-renewal and in vivo regenerative capacity of MaSCs are observed in th...

  4. Lessons learned using different mouse models during space radiation-induced lung tumorigenesis experiments

    Science.gov (United States)

    Wang, Jian; Zhang, Xiangming; Wang, Ping; Wang, Xiang; Farris, Alton B.; Wang, Ya

    2016-06-01

    Unlike terrestrial ionizing radiation, space radiation, especially galactic cosmic rays (GCR), contains high energy charged (HZE) particles with high linear energy transfer (LET). Due to a lack of epidemiologic data for high-LET radiation exposure, it is highly uncertain how high the carcinogenesis risk is for astronauts following exposure to space radiation during space missions. Therefore, using mouse models is necessary to evaluate the risk of space radiation-induced tumorigenesis; however, which mouse model is better for these studies remains uncertain. Since lung tumorigenesis is the leading cause of cancer death among both men and women, and low-LET radiation exposure increases human lung carcinogenesis, evaluating space radiation-induced lung tumorigenesis is critical to enable safe Mars missions. Here, by comparing lung tumorigenesis obtained from different mouse strains, as well as miR-21 in lung tissue/tumors and serum, we believe that wild type mice with a low spontaneous tumorigenesis background are ideal for evaluating the risk of space radiation-induced lung tumorigenesis, and circulating miR-21 from such mice model might be used as a biomarker for predicting the risk.

  5. Lessons learned using different mouse models during space radiation-induced lung tumorigenesis experiments.

    Science.gov (United States)

    Wang, Jian; Zhang, Xiangming; Wang, Ping; Wang, Xiang; Farris, Alton B; Wang, Ya

    2016-06-01

    Unlike terrestrial ionizing radiation, space radiation, especially galactic cosmic rays (GCR), contains high energy charged (HZE) particles with high linear energy transfer (LET). Due to a lack of epidemiologic data for high-LET radiation exposure, it is highly uncertain how high the carcinogenesis risk is for astronauts following exposure to space radiation during space missions. Therefore, using mouse models is necessary to evaluate the risk of space radiation-induced tumorigenesis; however, which mouse model is better for these studies remains uncertain. Since lung tumorigenesis is the leading cause of cancer death among both men and women, and low-LET radiation exposure increases human lung carcinogenesis, evaluating space radiation-induced lung tumorigenesis is critical to enable safe Mars missions. Here, by comparing lung tumorigenesis obtained from different mouse strains, as well as miR-21 in lung tissue/tumors and serum, we believe that wild type mice with a low spontaneous tumorigenesis background are ideal for evaluating the risk of space radiation-induced lung tumorigenesis, and circulating miR-21 from such mice model might be used as a biomarker for predicting the risk.

  6. TSPY potentiates cell proliferation and tumorigenesis by promoting cell cycle progression in HeLa and NIH3T3 cells

    Directory of Open Access Journals (Sweden)

    Chan Wai-Yee

    2006-06-01

    Full Text Available Abstract Background TSPY is a repeated gene mapped to the critical region harboring the gonadoblastoma locus on the Y chromosome (GBY, the only oncogenic locus on this male-specific chromosome. Elevated levels of TSPY have been observed in gonadoblastoma specimens and a variety of other tumor tissues, including testicular germ cell tumors, prostate cancer, melanoma, and liver cancer. TSPY contains a SET/NAP domain that is present in a family of cyclin B and/or histone binding proteins represented by the oncoprotein SET and the nucleosome assembly protein 1 (NAP1, involved in cell cycle regulation and replication. Methods To determine a possible cellular function for TSPY, we manipulated the TSPY expression in HeLa and NIH3T3 cells using the Tet-off system. Cell proliferation, colony formation assays and tumor growth in nude mice were utilized to determine the TSPY effects on cell growth and tumorigenesis. Cell cycle analysis and cell synchronization techniques were used to determine cell cycle profiles. Microarray and RT-PCR were used to investigate gene expression in TSPY expressing cells. Results Our findings suggest that TSPY expression increases cell proliferation in vitro and tumorigenesis in vivo. Ectopic expression of TSPY results in a smaller population of the host cells in the G2/M phase of the cell cycle. Using cell synchronization techniques, we show that TSPY is capable of mediating a rapid transition of the cells through the G2/M phase. Microarray analysis demonstrates that numerous genes involved in the cell cycle and apoptosis are affected by TSPY expression in the HeLa cells. Conclusion These data, taken together, have provided important insights on the probable functions of TSPY in cell cycle progression, cell proliferation, and tumorigenesis.

  7. Liver metastases

    Science.gov (United States)

    ... no symptoms. When symptoms occur, they may include: Decreased appetite Confusion Fever , sweating Jaundice (yellowing of the skin ... can include: Blockage of the flow of bile Decreased appetite Fever Liver failure (usually only in the late ...

  8. Liver Panel

    Science.gov (United States)

    ... GGT) – another enzyme found mainly in liver cells Lactate dehydrogenase (LD) – an enzyme released with cell damage; found ... and with conditions, such as congestive heart failure . Lactate dehydrogenase (LD) This is a non-specific marker of ...

  9. Liver function

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    2008308 Study on transplantation of induced bone marrow mesenchymal stem cells via a series of the treatment of chronic liver injury. SUN Yan(孙艳), et al. Dept Gastroenterol, 1st Hosp, Jilin Univ, Changchun 130021. Chin J Dig 2008;28(3):171-174.Objective To investigate the efficacy of transplantation of induced bone marrow mesenchymal stem cells(MSCs)via a series of treatment of chronic liver injury.Methods MSCs were isolated and expanded by density

  10. Conserved mechanisms of tumorigenesis in the Drosophila adult midgut.

    Directory of Open Access Journals (Sweden)

    Òscar Martorell

    Full Text Available Whereas the series of genetic events leading to colorectal cancer (CRC have been well established, the precise functions that these alterations play in tumor progression and how they disrupt intestinal homeostasis remain poorly characterized. Activation of the Wnt/Wg signaling pathway by a mutation in the gene APC is the most common trigger for CRC, inducing benign lesions that progress to carcinomas due to the accumulation of other genetic alterations. Among those, Ras mutations drive tumour progression in CRC, as well as in most epithelial cancers. As mammalian and Drosophila's intestines share many similarities, we decided to explore the alterations induced in the Drosophila midgut by the combined activation of the Wnt signaling pathway with gain of function of Ras signaling in the intestinal stem cells. Here we show that compound Apc-Ras clones, but not clones bearing the individual mutations, expand as aggressive intestinal tumor-like outgrowths. These lesions reproduce many of the human CRC hallmarks such as increased proliferation, blockade of cell differentiation and cell polarity and disrupted organ architecture. This process is followed by expression of tumoral markers present in human lesions. Finally, a metabolic behavioral assay shows that these flies suffer a progressive deterioration in intestinal homeostasis, providing a simple readout that could be used in screens for tumor modifiers or therapeutic compounds. Taken together, our results illustrate the conservation of the mechanisms of CRC tumorigenesis in Drosophila, providing an excellent model system to unravel the events that, upon mutation in Apc and Ras, lead to CRC initiation and progression.

  11. Molecular mechanisms of thyroid tumorigenesis; Molekulare Mechanismen der Schilddruesentumorgenese

    Energy Technology Data Exchange (ETDEWEB)

    Krause, K.; Fuehrer, D. [Universitaetsklinikum Leipzig (Germany). Abt. fuer Endokrinolgoie, Diabetologie und Nephrologie

    2008-09-15

    Thyroid nodules are the most frequent endocrine disorder and occur in approximately 30% of the German population. Thyroid nodular disease constitutes a very heterogeneous entity. A striking diversity of possible functional and morphological features of a thyroid tumour derived from the same thyroid ancestor cell, is a hallmark of thyroid tumorigenesis and is due to specific genetic alterations. Defects in known candidate genes can be found in up to 70% of differentiated thyroid carcinomas and determine the respective cancer phenotype. Papillary thyroid cancers (PTC) harbour BRAF (or much less frequently RAS) mutations in sporadically occurring tumours, while radiation-induced PTC display chromosomal rearrangements such as RET, TRK, APR9 / BRAF. These genetic events results in constitutive MAPKinase activation. Follicular thyroid cancers (FTC) harbour RAS mutations or PAX8/ PPAR{gamma} rearrangements, both of which, however have also been identified in follicular adenoma. In addition, recent studies show, that activation of PI3K/AKT signalling occurs with high frequency in follicular thyroid tumours. Undifferentiated (anaplastic) thyroid cancers (ATC) display genetic features of FTC or PTC, in addition to aberant activation of multiple tyrosinkinase pathways (overexpression or mutations in PI3K and MAPK pathways). This underscores the concept of a sequential evolution of ATC from differentiated thyroid cancer, a process widely conceived to be triggered by p53 inactivation. In contrast, the molecular pathogenesis of benign thyroid tumours, in particular cold thyroid nodules is less known, except for toxic thyroid nodules, which arise from constitutive activation of cAMP signalling, predominantly through TSHR mutations. (orig.)

  12. Autophagy regulates UBC9 levels during viral-mediated tumorigenesis

    Science.gov (United States)

    Mattoscio, Domenico; Casadio, Chiara; Miccolo, Claudia; Maffini, Fausto; Raimondi, Andrea; Tacchetti, Carlo; Gheit, Tarik; Tagliabue, Marta; Galimberti, Viviana E.; De Lorenzi, Francesca; Chiesa, Fausto; Ansarin, Mohssen; Tommasino, Massimo

    2017-01-01

    UBC9, the sole E2-conjugating enzyme required for SUMOylation, is a key regulator of essential cellular functions and, as such, is frequently altered in cancers. Along these lines, we recently reported that its expression gradually increases during early stages of human papillomavirus (HPV)-mediated cervical lesions transformation. However, a better understanding of how UBC9 is exploited by transforming viral oncoproteins is still needed. In the present study, we show that in human samples HPV drives UBC9 up-regulation also in very early steps of head and neck tumorigenesis, pointing to the important role for UBC9 in the HPV-mediated carcinogenic program. Moreover, using HPV-infected pre-cancerous tissues and primary human keratinocytes as the natural host of the virus, we investigate the pathological meaning and the cellular mechanisms responsible for UBC9 de-regulation in an oncoviral context. Our results show that UBC9 overexpression is promoted by transforming viral proteins to increase host cells’ resistance to apoptosis. In addition, ultrastuctural, pharmacological and genetic approaches crucially unveil that UBC9 is physiologically targeted by autophagy in human cells. However, the presence of HPV E6/E7 oncoproteins negatively impacts the autophagic process through selective inhibition of autophagosome-lysosome fusion, finally leading to p53 dependent UBC9 accumulation during viral-induced cellular transformation. Therefore, our study elucidates how UBC9 is manipulated by HPV oncoproteins, details the physiological mechanism by which UBC9 is degraded in cells, and identifies how HPV E6/E7 impact on autophagy. These findings point to UBC9 and autophagy as novel hallmarks of HPV oncogenesis, and open innovative avenues towards the treatment of HPV-related malignancies. PMID:28253371

  13. Interaction of tomato lycopene and ketosamine against rat prostate tumorigenesis.

    Science.gov (United States)

    Mossine, Valeri V; Chopra, Pankaj; Mawhinney, Thomas P

    2008-06-01

    Prior investigations on the beneficial effect of dietary processed tomato products and lycopene on prostate cancer risk suggested that lycopene may require the presence of other constituents to exert its chemopreventive potential. We investigated whether ketosamines, a group of carbohydrate derivatives present in dehydrated tomato products, may interact with lycopene against prostate tumorigenesis. One ketosamine, FruHis, strongly synergized with lycopene against proliferation of the highly metastatic rat prostate adenocarcinoma MAT-LyLu cell line in vitro. The FruHis/lycopene combination significantly inhibited in vivo tumor formation by MAT-LyLu cells in syngeneic Copenhagen rats. Energy-balanced diets, supplemented with tomato paste, tomato powder, or tomato paste plus FruHis, were fed to Wistar-Unilever rats (n = 20 per group) treated with N-nitroso-N-methylurea and testosterone to induce prostate carcinogenesis. Survival from carcinogenesis was lowest in the control group (median survival time, 40 weeks) and highest in the group fed the tomato paste/FruHis diet (51 weeks; P = 0.004, versus control). The proportions of dying rats with macroscopic prostate tumors in the control, tomato paste, tomato powder, and tomato paste/FruHis groups were 63% (12 of 19), 39% (5 of 13), 43% (6 of 14), and 18% (2 of 11), respectively. FruHis completely blocked DNA oxidative degradation at >250 micromol/L in vitro, whereas neither ascorbate nor phenolic antioxidants from tomato were effective protectors in this assay. FruHis, therefore, may exert tumor-preventive effect through its antioxidant activity and interaction with lycopene.

  14. Cyr61 promotes breast tumorigenesis and cancer progression

    Energy Technology Data Exchange (ETDEWEB)

    Tsai, Miaw-Sheue; Bogart, Daphne F.; Castaneda, Jessica M.; Li, Patricia; Lupu, Ruth

    2002-01-16

    Cyr61, a member of the CCN family of genes, is an angiogenic factor. We have shown that it is overexpressed in invasive and metastatic human breast cancer cells and tissues. Here, we investigated whether Cyr61 is necessary and/or sufficient to bypass the ''normal'' estrogen (E2) requirements for breast cancer cell growth. Our results demonstrate that under E2-depleted condition, Cyr61 is sufficient to induce MCF-7 cells grow in the absence of E2. MCF-7 cells transfected with Cyr61 (MCF-7/Cyr61) became E2-independent but still E2-responsive. On the other hand, MCF-7/vector cells remain E2-dependent. MCF-7/Cyr61 cells acquire an antiestrogen-resistant phenotype, one of the most common clinical occurrences during breast cancer progression. MCF-7/Cyr61 cells are anchorage-independent and capable of forming Matrigel outgrowth patterns in the absence of E2. ERa expression in MCF-7/Cyr61 cells is decreased although still functional. Additionally, MCF-7/Cyr61 cells are tumorigenic in ovariectomized athymic nude mice. The tumors resemble human invasive carcinomas with increased vascularization and overexpression of vascular endothelial growth factor (VEGF). Our results demonstrate that Cyr61 is a tumor-promoting factor and a key regulator of breast cancer progression. This study provides evidence that Cyr61 is sufficient to induce E2-independence and anti-E2 resistance, and to promote invasiveness in vitro, and to induce tumorigenesis in vivo, all of which are characteristics of an aggressive breast cancer phenotype.

  15. Biomarkers in Tumorigenesis Using Cancer Cell Lines: A Systematic Review

    Science.gov (United States)

    Raju K, Lizbeth; Augustine, Dominic; Rao, Roopa S; S V, Sowmya; Haragannavar, Vanishri C; Nambiar, Shwetha; Prasad, Kavitha; Awan, Kamran Habib; Patil, Shankargouda

    2017-09-27

    Cancer is a leading cause of death worldwide. Despite many research advancements in the field, the genetic changes regulating the transformation of normal oral cells into malignant cells have not been fully elucidated. Several studies have evaluated carcinogenesis at the molecular level. Cancer cell lines are commonly used in biomedical research because they provide an unlimited source of cells and represent various stages of initiation and progression of carcinogenesis in vitro. Aims: The objective of the study was to review original research articles using cancer cell lines as a tool to understand carcinogenesis and to identify the genes involved in tumor development. Additionally, we also examined the application of the genes as predictive biomarkers. Methods and Materials: Several databases, including PubMed, Google Scholar, Ebsco, and Science Direct, were searched from 1985 to December 2016 using various combinations of the following key words: “mouth neoplasm”, “cell lines”, and “tumorigenesis”. Original experimental studies published in English were included. We excluded letters to the editor, historic reviews, and unpublished data from the analysis. Results: There were 17 studies (in vitro) included in the analysis. There were 14 genes and 4 miRNAs involved in malignant transformation of oral keratinocytes into cancer cells. The most commonly studied genes were p53, cyclin D1, and hTERT. Conclusion: Additional reviews and studies are needed to identify a panel of genes specific to various potentially malignant disorders and to aid in the early detection of oral squamous cell carcinoma (OSCC) because tumorigenesis involves the mutation of multiple genes. Furthermore, improving advanced cost-effective diagnostic methods may benefit the public health sector. Creative Commons Attribution License

  16. Implication of Heat Shock Factors in Tumorigenesis: Therapeutical Potential

    Energy Technology Data Exchange (ETDEWEB)

    Thonel, Aurelie de [INSERM U866, Dijon (France); Faculty of Medicine and Pharmacy, University of Burgundy, 21033 Dijon (France); Mezger, Valerie, E-mail: valerie.mezger@univ-paris-diderot.fr [CNRS, UMR7216 Epigenetics and Cell Fate, Paris (France); University Paris Diderot, 75013 Paris (France); Garrido, Carmen, E-mail: valerie.mezger@univ-paris-diderot.fr [INSERM U866, Dijon (France); Faculty of Medicine and Pharmacy, University of Burgundy, 21033 Dijon (France); CHU, Dijon BP1542, Dijon (France)

    2011-03-07

    Heat Shock Factors (HSF) form a family of transcription factors (four in mammals) which were named according to the discovery of their activation by a heat shock. HSFs trigger the expression of genes encoding Heat Shock Proteins (HSPs) that function as molecular chaperones, contributing to establish a cytoprotective state to various proteotoxic stresses and in pathological conditions. Increasing evidence indicates that this ancient transcriptional protective program acts genome-widely and performs unexpected functions in the absence of experimentally defined stress. Indeed, HSFs are able to re-shape cellular pathways controlling longevity, growth, metabolism and development. The most well studied HSF, HSF1, has been found at elevated levels in tumors with high metastatic potential and is associated with poor prognosis. This is partly explained by the above-mentioned cytoprotective (HSP-dependent) function that may enable cancer cells to adapt to the initial oncogenic stress and to support malignant transformation. Nevertheless, HSF1 operates as major multifaceted enhancers of tumorigenesis through, not only the induction of classical heat shock genes, but also of “non-classical” targets. Indeed, in cancer cells, HSF1 regulates genes involved in core cellular functions including proliferation, survival, migration, protein synthesis, signal transduction, and glucose metabolism, making HSF1 a very attractive target in cancer therapy. In this review, we describe the different physiological roles of HSFs as well as the recent discoveries in term of non-cogenic potential of these HSFs, more specifically associated to the activation of “non-classical” HSF target genes. We also present an update on the compounds with potent HSF1-modulating activity of potential interest as anti-cancer therapeutic agents.

  17. Autophagy regulator BECN1 suppresses mammary tumorigenesis driven by WNT1 activation and following parity.

    Science.gov (United States)

    Cicchini, Michelle; Chakrabarti, Rumela; Kongara, Sameera; Price, Sandy; Nahar, Ritu; Lozy, Fred; Zhong, Hua; Vazquez, Alexei; Kang, Yibin; Karantza, Vassiliki

    2014-01-01

    Earlier studies reported allelic deletion of the essential autophagy regulator BECN1 in breast cancers implicating BECN1 loss, and likely defective autophagy, in tumorigenesis. Recent studies have questioned the tumor suppressive role of autophagy, as autophagy-related gene (Atg) defects generally suppress tumorigenesis in well-characterized mouse tumor models. We now report that, while it delays or does not alter mammary tumorigenesis driven by Palb2 loss or ERBB2 and PyMT overexpression, monoallelic Becn1 loss promotes mammary tumor development in 2 specific contexts, namely following parity and in association with wingless-type MMTV integration site family, member 1 (WNT1) activation. Our studies demonstrate that Becn1 heterozygosity, which results in immature mammary epithelial cell expansion and aberrant TNFRSF11A/TNR11/RANK (tumor necrosis factor receptor superfamily, member 11a, NFKB activator) signaling, promotes mammary tumorigenesis in multiparous FVB/N mice and in cooperation with the progenitor cell-transforming WNT1 oncogene. Similar to our Becn1(+/-);MMTV-Wnt1 mouse model, low BECN1 expression and an activated WNT pathway gene signature correlate with the triple-negative subtype, TNFRSF11A axis activation and poor prognosis in human breast cancers. Our results suggest that BECN1 may have nonautophagy-related roles in mammary development, provide insight in the seemingly paradoxical roles of BECN1 in tumorigenesis, and constitute the basis for further studies on the pathophysiology and treatment of clinically aggressive triple negative breast cancers (TNBCs).

  18. Pitavastatin suppresses diethylnitrosamine-induced liver preneoplasms in male C57BL/KsJ-db/db obese mice

    Directory of Open Access Journals (Sweden)

    Kochi Takahiro

    2011-06-01

    Full Text Available Abstract Background Obesity and related metabolic abnormalities, including inflammation and lipid accumulation in the liver, play a role in liver carcinogenesis. Adipocytokine imbalances, such as decreased serum adiponectin levels, are also involved in obesity-related liver tumorigenesis. In the present study, we examined the effects of pitavastatin - a drug used for the treatment of hyperlipidemia - on the development of diethylnitrosamine (DEN-induced liver preneoplastic lesions in C57BL/KsJ-db/db (db/db obese mice. Methods Male db/db mice were administered tap water containing 40 ppm DEN for 2 weeks and were subsequently fed a diet containing 1 ppm or 10 ppm pitavastatin for 14 weeks. Results At sacrifice, feeding with 10 ppm pitavastatin significantly inhibited the development of hepatic premalignant lesions, foci of cellular alteration, as compared to that in the untreated group by inducing apoptosis, but inhibiting cell proliferation. Pitavastatin improved liver steatosis and activated the AMPK-α protein in the liver. It also decreased free fatty acid and aminotransferases levels, while increasing adiponectin levels in the serum. The serum levels of tumor necrosis factor (TNF-α and the expression of TNF-α and interleukin-6 mRNAs in the liver were decreased by pitavastatin treatment, suggesting attenuation of the chronic inflammation induced by excess fat deposition. Conclusions Pitavastatin is effective in inhibiting the early phase of obesity-related liver tumorigenesis and, therefore, may be useful in the chemoprevention of liver cancer in obese individuals.

  19. The Yin-Yang of DNA Damage Response: Roles in Tumorigenesis and Cellular Senescence

    Directory of Open Access Journals (Sweden)

    Sang Soo Kim

    2013-01-01

    Full Text Available Senescent cells are relatively stable, lacking proliferation capacity yet retaining metabolic activity. In contrast, cancer cells are rather invasive and devastating, with uncontrolled proliferative capacity and resistance to cell death signals. Although tumorigenesis and cellular senescence are seemingly opposite pathological events, they are actually driven by a unified mechanism: DNA damage. Integrity of the DNA damage response (DDR network can impose a tumorigenesis barrier by navigating abnormal cells to cellular senescence. Compromise of DDR, possibly due to the inactivation of DDR components, may prevent cellular senescence but at the expense of tumor formation. Here we provide an overview of the fundamental role of DDR in tumorigenesis and cellular senescence, under the light of the Yin-Yang concept of Chinese philosophy. Emphasis is placed on discussing DDR outcome in the light of in vivo models. This information is critical as it can help make better decisions for clinical treatments of cancer patients.

  20. Autophagy in tumorigenesis and cancer therapy: Dr. Jekyll or Mr. Hyde?

    Science.gov (United States)

    Zhou, Shengtao; Zhao, Linjie; Kuang, Manchao; Zhang, Bingjie; Liang, Zhu; Yi, Tao; Wei, Yuquan; Zhao, Xia

    2012-10-28

    Autophagy is an evolutionarily conserved mechanism for intracellular substance degradation, responsible for the recycling of metabolic substances and the maintenance of intracellular stability. It has early been demonstrated to play a significant role in tumorigenesis, but whether it acts as a promoter or a suppressor during tumorigenesis seems to be context-specific. Moreover, autophagy is also implicated in promoting chemoresistance of cancer cells so as to attenuate therapeutic efficacy of chemotherapy. On the contrary, other reports highlight a tumor-killing role of autophagy during cancer treatment. Herein, this review aims to revisit the key features of autophagy, summarize the seemingly contradictory roles of autophagy during both tumorigenesis and cancer chemotherapy, and evaluate the feasibility of altering the level of cellular autophagy as part of cancer adjuvant treatment. Copyright © 2012. Published by Elsevier Ireland Ltd.

  1. Circadian disruption induced by light-at-night accelerates aging and promotes tumorigenesis in rats

    Science.gov (United States)

    Vinogradova, Irina A.; Anisimov, Vladimir N.; Bukalev, Andrey V.; Semenchenko, Anna V.; Zabezhinski, Mark A.

    2009-01-01

    We evaluated the effect of various light/dark regimens on the survival, life span and tumorigenesis in rats. Two hundred eight male and 203 females LIO rats were subdivided into 4 groups and kept at various light/dark regimens: standard 12:12 light/dark (LD); natural lighting of the North-West of Russia (NL); constant light (LL), and constant darkness (DD) since the age of 25 days until natural death. We found that exposure to NL and LL regimens accelerated development of metabolic syndrome and spontaneous tumorigenesis, shortened life span both in male and females rats as compared to the standard LD regimen. We conclude that circadian disruption induced by light-at-night accelerates aging and promotes tumorigenesis in rats. This observation supports the conclusion of the International Agency Research on Cancer that shift-work that involves circadian disruption is probably carcinogenic to humans. PMID:20157558

  2. Liver Wellness

    Science.gov (United States)

    ... can cause the liver to swell and not work well. Prevention: Hepatitis A vaccination is the best way to prevent HAV. Other ways to stop the spread of HAV are: • Always washing your hands with soap and warm water immediately after using the bathroom ...

  3. Liver Biopsy

    Science.gov (United States)

    ... and sends the sample to a lab for analysis. People with severe liver disease often have blood-clotting problems that can increase their chance of ... called collapsed lung, which occurs when air or gas builds up in the pleural space. ... of blood in the pleural space. puncture of other organs. ...

  4. Elevated Liver Enzymes

    Science.gov (United States)

    Symptoms Elevated liver enzymes By Mayo Clinic Staff Elevated liver enzymes may indicate inflammation or damage to cells in the liver. Inflamed or ... than normal amounts of certain chemicals, including liver enzymes, into the bloodstream, which can result in elevated ...

  5. Tests for Liver Cancer

    Science.gov (United States)

    ... Cancer Early Detection, Diagnosis, and Staging Tests for Liver Cancer If you have some of the signs ... Health Care Team About Liver Cancer? More In Liver Cancer About Liver Cancer Causes, Risk Factors, and ...

  6. Liver cancer - hepatocellular carcinoma

    Science.gov (United States)

    Primary liver cell carcinoma; Tumor - liver; Cancer - liver; Hepatoma ... Hepatocellular carcinoma accounts for most liver cancers. This type of cancer occurs more often in men than women. It is usually diagnosed in people age 50 or ...

  7. Liver Transplant: Nutrition

    Science.gov (United States)

    ... ZIP code here Enter ZIP code here Liver Transplant: Nutrition for Veterans and the Public Nutrition Liver ... apply to transplant and liver disease patients. Pre-Transplant Protein Malnutrition -- Many patients with end stage liver ...

  8. Liver Function Tests

    Science.gov (United States)

    ... Baby Boomers Get Tested Core Programs HE Webinar Disney 2014 5 Ways to Love Your Liver Liver ... Drive Away Liver Disease Liver Lowdown Aug 2013 Disney Marathon In The Field Healthy Foods Diet Recommendations ...

  9. Liver cirrhosis and fatty liver

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    2008075 Effect of Jiangzhi granules on expression of leptin receptor mRNA, P-JAK2 and P-STAT3 in rats with non-alcoholic fatty liver disease. MA Zansong(马赞颂), et al. Dept Gastroenterol, Instit Spleen and Stomach Dis, Longhua Hosp. Shanghai TCM Univ, Shanghai 200032.World Chin J Digestol 2007;15(32):3360-3366. Objective To study the effect of Jiangzhi granules on non-alcoholic fatty liver disease in rats, and on the expression of

  10. Fecal excretion pattern of bile acids in rats fed high fat diets and neomycin in induced colon tumorigenesis.

    Science.gov (United States)

    Panda, S K; Broitman, S A

    1999-09-06

    Neomycin augments colon tumorigenesis in 1,2 - dimethylhydrazine treated rats fed polyunsaturated fat diet and decreases fecal cholic acid excretion, while it inhibits tumorigenesis with increased cholic acid and decreased deoxycholic acid excretions in rats fed high cholesterol diet. Participation of other fecal bile acids seems to be insignificant in relation to colon carcinogenesis.

  11. Liver cirrhosis and fatty liver

    Institute of Scientific and Technical Information of China (English)

    1997-01-01

    970345 An experimental and clinical study on α1-adrenergic receptor of liver plasma membranes in cir-rhosis with portal hypertension. ZHANG Youcheng(张有成), et al. Dept Surg, People’s Hosp, Beijing MedUniv, Beijing, 100044 Chin J Dig 1996; 16(6): 332-335.

  12. Upregulation of the PI3K/Akt pathway in the tumorigenesis of canine thyroid carcinoma

    NARCIS (Netherlands)

    Campos, M; Kool, M M J; Daminet, S; Ducatelle, R; Rutteman, G; Kooistra, H S; Galac, S; Mol, J A

    2014-01-01

    BACKGROUND: Information on the genetic events leading to thyroid cancer in dogs is lacking. HYPOTHESIS/OBJECTIVES: Upregulation of the PI3K/Akt pathway has an important role in the tumorigenesis of thyroid carcinoma in dogs. ANIMALS: Fifty-nine dogs with thyroid carcinoma and 10 healthy controls. ME

  13. For better or for worse : the role of Pim oncogenes in tumorigenesis

    NARCIS (Netherlands)

    Nawijn, Martijn C.; Alendar, Andrej; Berns, Anton

    2011-01-01

    Pim oncogenes are overexpressed in a wide range of tumours from a haematological and epithelial origin. Pim genes encode serine/threonine kinases that have been shown to counteract the increased sensitivity to apoptosis induction that is associated with MYC-driven tumorigenesis. Recently, considerab

  14. Chemoprevention of intestinal tumorigenesis by nabumetone: induction of apoptosis and Bcl-2 downregulation.

    Science.gov (United States)

    Roy, H K; Karoski, W J; Ratashak, A; Smyrk, T C

    2001-05-18

    Treatment of MIN mice with the nonsteroidal anti-inflammatory drug, nabumetone, resulted in a dose-dependent suppression of intestinal tumorigenesis. In both the uninvolved MIN mouse colonic epithelium and HT-29 colon cancer cells, nabumetone downregulated the anti-apoptotic protein, Bcl-2, with concomitant induction of apoptosis, suggesting a potential mechanism for colon cancer chemoprevention.

  15. Liver cirrhosis and fatty liver

    Institute of Scientific and Technical Information of China (English)

    1993-01-01

    930137 Effects of selective and non-selectiveβ-adrenoreceptor blockers on portal hemody-namics in patients with liver cirrhosis.HUANGTianwei(黄天卫),et al.1st Affili Hosp,DalianMed Coll.Chin J Digest 1992;12(3):145-147.Effects of selective(atenolol)and non-selec-tive(propranolol)β-adrenoreceptor blockerson portal hemodynamics in patients with livercirrhosis were measured by pulsed Doppler du-

  16. Liver in systemic disease

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Potential causes of abnormal liver function tests include viral hepatitis, alcohol intake, nonalcoholic fatty liver disease, autoimmune liver diseases, hereditary diseases, hepatobiliary malignancies or infection, gallstones and drug-induced liver injury. Moreover, the liver may be involved in systemic diseases that mainly affect other organs. Therefore, in patients without etiology of liver injury by screening serology and diagnostic imaging, but who have systemic diseases, the abnormal liver function test results might be caused by the systemic disease. In most of these patients, the systemic disease should be treated primarily. However, some patients with systemic disease and severe liver injury or fulminant hepatic failure require intensive treatments of the liver.

  17. The commonly used antimicrobial additive triclosan is a liver tumor promoter.

    Science.gov (United States)

    Yueh, Mei-Fei; Taniguchi, Koji; Chen, Shujuan; Evans, Ronald M; Hammock, Bruce D; Karin, Michael; Tukey, Robert H

    2014-12-02

    Triclosan [5-chloro-2-(2,4-dichlorophenoxy)phenol; TCS] is a synthetic, broad-spectrum antibacterial chemical used in a wide range of consumer products including soaps, cosmetics, therapeutics, and plastics. The general population is exposed to TCS because of its prevalence in a variety of daily care products as well as through waterborne contamination. TCS is linked to a multitude of health and environmental effects, ranging from endocrine disruption and impaired muscle contraction to effects on aquatic ecosystems. We discovered that TCS was capable of stimulating liver cell proliferation and fibrotic responses, accompanied by signs of oxidative stress. Through a reporter screening assay with an array of nuclear xenobiotic receptors (XenoRs), we found that TCS activates the nuclear receptor constitutive androstane receptor (CAR) and, contrary to previous reports, has no significant effect on mouse peroxisome proliferation activating receptor α (PPARα). Using the procarcinogen diethylnitrosamine (DEN) to initiate tumorigenesis in mice, we discovered that TCS substantially accelerates hepatocellular carcinoma (HCC) development, acting as a liver tumor promoter. TCS-treated mice exhibited a large increase in tumor multiplicity, size, and incidence compared with control mice. TCS-mediated liver regeneration and fibrosis preceded HCC development and may constitute the primary tumor-promoting mechanism through which TCS acts. These findings strongly suggest there are adverse health effects in mice with long-term TCS exposure, especially on enhancing liver fibrogenesis and tumorigenesis, and the relevance of TCS liver toxicity to humans should be evaluated.

  18. Pentoxifylline prevents nonalcoholic steatohepatitis-related liver pre-neoplasms by inhibiting hepatic inflammation and lipogenesis.

    Science.gov (United States)

    Shirakami, Yohei; Shimizu, Masahito; Kubota, Masaya; Ohno, Tomohiko; Kochi, Takahiro; Nakamura, Nobuhiko; Sumi, Takafumi; Tanaka, Takuji; Moriwaki, Hisataka; Seishima, Mitsuru

    2016-05-01

    Nonalcoholic steatohepatitis (NASH) has gained attention as a hepatic manifestation associated with metabolic syndrome and one of the causes for chronic liver damage leading to hepatocellular carcinoma. Although no standard medicinal treatment for NASH has been established, pentoxifylline (PTX), a medicine used to improve circulation, has recently been reported to ameliorate the histopathological appearance of NASH. In the present study, we investigated the effects of PTX on the development of NASH and diethylnitrosamine-induced liver tumorigenesis in C57BLKS/J- +Lepr/+Lepr obese and diabetic mice, which are considered a rodent model for NASH-related hepatocarcinogenesis. Mice were administered diethylnitrosamine, and then they received water with or without PTX. At the time of sacrifice, the development of hepatic pre-neoplastic lesions was significantly suppressed in the PTX groups. Hepatic triglyceride contents were decreased by PTX administration. The serum levels of triglyceride, free fatty acid, and alanine aminotransferase were all decreased by PTX treatment, as was the mRNA expression of proinflammatory cytokines, macrophage-inducing chemokines, and several lipogenic genes in the liver. In-vitro studies also showed that PTX treatment decreased the expression of several lipogenic genes and chemokines in cell lines. These findings suggest that PTX prevents NASH-related liver tumorigenesis by attenuating chronic hepatic inflammation and decreasing lipogenic gene expression in the liver.

  19. Liver transplant for cholestatic liver diseases.

    Science.gov (United States)

    Carrion, Andres F; Bhamidimarri, Kalyan Ram

    2013-05-01

    Cholestatic liver diseases include a group of diverse disorders with different epidemiology, pathophysiology, clinical course, and prognosis. Despite significant advances in the clinical care of patients with cholestatic liver diseases, liver transplant (LT) remains the only definitive therapy for end-stage liver disease, regardless of the underlying cause. As per the United Network for Organ Sharing database, the rate of cadaveric LT for cholestatic liver disease was 18% in 1991, 10% in 2000, and 7.8% in 2008. This review summarizes the available evidence on various common and rare cholestatic liver diseases, disease-specific issues, and pertinent aspects of LT.

  20. Identification of cytochrome P450 enzymes critical for lung tumorigenesis by the tobacco-specific carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK): insights from a novel Cyp2abfgs-null mouse.

    Science.gov (United States)

    Li, Lei; Megaraj, Vandana; Wei, Yuan; Ding, Xinxin

    2014-11-01

    Cytochrome P450 (P450) enzymes encoded by the mouse Cyp2abfgs gene cluster are preferentially expressed in the respiratory tract. Previous studies have demonstrated that pulmonary P450-mediated bioactivation is necessary for lung tumorigenesis induced by the tobacco-specific lung procarcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), and that CYP2A5 mediates a noteworthy fraction, but not all, of NNK bioactivation in the lung. The aim of this study was to determine whether other P450s encoded by the Cyp2abfgs gene cluster also play significant roles in NNK lung tumorigenesis. A novel Cyp2abfgs-null mouse was generated, in which all Cyp2a, 2b, 2g, 2f and 2s genes are deleted. The Cyp2abfgs-null mouse was viable, fertile and without discernible physiological abnormalities or compensatory increases in the expression of other P450s. NNK bioactivation in vitro and NNK-induced DNA adduction and lung tumorigenesis in vivo were determined for wild-type (WT) and Cyp2abfgs-null mice; the results were compared with previous findings from Cyp2a5-null mice. The Cyp2abfgs-null mice exhibited significantly lower rates of NNK bioactivation in lung and liver microsomes, compared with either WT or Cyp2a5-null mice. The levels of lung O(6)-methyl guanine DNA adduct were also substantially reduced in Cyp2abfgs-null mice, compared with either WT or Cyp2a5-null mice. Moreover, the Cyp2abfgs-null mice were largely resistant to NNK-induced lung tumorigenesis at both low (50mg/kg) and high (200mg/kg) NNK doses, in contrast to the WT or Cyp2a5-null mice. These results indicate for the first time that, collectively, the CYP2A, 2B, 2F, 2G, and 2S enzymes are indispensable for NNK-induced lung tumorigenesis.

  1. Microenvironment of liver regeneration in liver cancer.

    Science.gov (United States)

    Li, Han-Min; Ye, Zhi-Hua

    2017-07-01

    The occurrence and development of liver cancer are essentially the most serious outcomes of uncontrolled liver regeneration. The progression of liver cancer is inevitably related to the abnormal microenvironment of liver regeneration. The deterioration observed in the microenvironment of liver regeneration is a necessary condition for the occurrence, development and metastasis of cancer. Therefore, the use of a technique to prevent and treat liver cancer via changes in the microenvironment of liver regeneration is a novel strategy. This strategy would be an effective way to delay, prevent or even reverse cancer occurrence, development and metastasis through an improvement in the liver regeneration microenvironment along with the integrated regulation of multiple components, targets, levels, channels and time sequences. In addition, the treatment of "tonifying Shen (Kidney) to regulate liver regeneration and repair by affecting stem cells and their microenvironment" can regulate "the dynamic imbalance between the normal liver regeneration and the abnormal liver regeneration"; this would improve the microenvironment of liver regeneration, which is also a mechanism by which liver cancer may be prevented or treated.

  2. Pyogenic liver abscess

    Science.gov (United States)

    Liver abscess; Bacterial liver abscess ... There are many possible causes of liver abscesses, including: Abdominal infection, such as appendicitis , diverticulitis , or a perforated bowel Infection in the blood Infection of the bile draining tubes ...

  3. Liver Disease and IBD

    Science.gov (United States)

    ... Home > Resources > Liver Disease and IBD Go Back Liver Disease and IBD Email Print + Share Several complications ... be necessary to make the definitive diagnosis. FATTY LIVER DISEASE (HEPATCI STEATOSIS) This is the most common ...

  4. Liver Function Tests

    Science.gov (United States)

    ... food, store energy, and remove poisons. Liver function tests are blood tests that check to see how well your liver ... hepatitis and cirrhosis. You may have liver function tests as part of a regular checkup. Or you ...

  5. Regenerative medicine using dental pulp stem cells for liver diseases

    Science.gov (United States)

    Ohkoshi, Shogo; Hara, Hajime; Hirono, Haruka; Watanabe, Kazuhiko; Hasegawa, Katsuhiko

    2017-01-01

    Acute liver failure is a refractory disease and its prognosis, if not treated using liver transplantation, is extremely poor. It is a good candidate for regenerative medicine, where stem cell-based therapies play a central role. Mesenchymal stem cells (MSCs) are known to differentiate into multiple cell lineages including hepatocytes. Autologous cell transplant without any foreign gene induction is feasible using MSCs, thereby avoiding possible risks of tumorigenesis and immune rejection. Dental pulp also contains an MSC population that differentiates into hepatocytes. A point worthy of special mention is that dental pulp can be obtained from deciduous teeth during childhood and can be subsequently harvested when necessary after deposition in a tooth bank. MSCs have not only a regenerative capacity but also act in an anti-inflammatory manner via paracrine mechanisms. Promising efficacies and difficulties with the use of MSC derived from teeth are summarized in this review. PMID:28217369

  6. Adipokines and Non-Alcoholic Fatty Liver Disease: Multiple Interactions

    Directory of Open Access Journals (Sweden)

    Timon E. Adolph

    2017-07-01

    Full Text Available Accumulating evidence links obesity with low-grade inflammation which may originate from adipose tissue that secretes a plethora of pro- and anti-inflammatory cytokines termed adipokines. Adiponectin and leptin have evolved as crucial signals in many obesity-related pathologies including non-alcoholic fatty liver disease (NAFLD. Whereas adiponectin deficiency might be critically involved in the pro-inflammatory state associated with obesity and related disorders, overproduction of leptin, a rather pro-inflammatory mediator, is considered of equal relevance. An imbalanced adipokine profile in obesity consecutively contributes to metabolic inflammation in NAFLD, which is associated with a substantial risk for developing hepatocellular carcinoma (HCC also in the non-cirrhotic stage of disease. Both adiponectin and leptin have been related to liver tumorigenesis especially in preclinical models. This review covers recent advances in our understanding of some adipokines in NAFLD and associated HCC.

  7. Amebic liver abscess

    Science.gov (United States)

    Hepatic amebiasis; Extraintestinal amebiasis; Abscess - amebic liver ... Amebic liver abscess is caused by Entamoeba histolytica. This parasite causes amebiasis , an intestinal infection that is also called ...

  8. MiR-218 Mediates tumorigenesis and metastasis: Perspectives and implications

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Ying-fei [Institute Guangzhou of Advanced Technology, Chinese Academy of Sciences, Guangzhou (China); Department of Orthopaedics & Traumatology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong (China); Zhang, Li [School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong (China); Department of Anatomical and Cellular Pathology, State Key Laboratory of Oncology in South China, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong (China); Waye, Mary Miu Yee [School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong (China); Fu, Wei-ming, E-mail: wm.fu@giat.ac.cn [Institute Guangzhou of Advanced Technology, Chinese Academy of Sciences, Guangzhou (China); School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong (China); Zhang, Jin-fang, E-mail: zhangjf06@cuhk.edu.hk [Department of Orthopaedics & Traumatology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong (China); School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong (China); Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen (China)

    2015-05-15

    MicroRNAs (miRNAs) are a class of small non-coding RNAs that negatively regulate gene expression at the post-transcriptional level. As a highly conserved miRNA across a variety of species, microRNA-218 (miR-218) was found to play pivotal roles in tumorigenesis and progression. A group of evidence has demonstrated that miR-218 acts as a tumor suppressor by targeting many oncogenes related to proliferation, apoptosis and invasion. In this review, we provide a complex overview of miR-218, including its regulatory mechanisms, known functions in cancer and future challenges as a potential therapeutic target in human cancers. - Highlights: • miR-218 is frequently down regulated in multiple cancers. • miR-218 plays pivotal roles in carcinogenesis. • miR-218 mediates proliferation, apoptosis, metastasis, invasion, etc. • miR-218 mediates tumorigenesis and metastasis via multiple pathways.

  9. Alveolar rhabdomyosarcoma – The molecular drivers of PAX3/7-FOXO1-induced tumorigenesis

    Directory of Open Access Journals (Sweden)

    Marshall Amy D

    2012-12-01

    Full Text Available Abstract Rhabdomyosarcoma is a soft tissue sarcoma arising from cells of a mesenchymal or skeletal muscle lineage. Alveolar rhabdomyosarcoma (ARMS is more aggressive than the more common embryonal (ERMS subtype. ARMS is more prone to metastasis and carries a poorer prognosis. In contrast to ERMS, the majority of ARMS tumors carry one of several characteristic chromosomal translocations, such as t(2;13(q35;q14, which results in the expression of a PAX3-FOXO1 fusion transcription factor. In this review we discuss the genes that cooperate with PAX3-FOXO1, as well as the target genes of the fusion transcription factor that contribute to various aspects of ARMS tumorigenesis. The characterization of these pathways will lead to a better understanding of ARMS tumorigenesis and will allow the design of novel targeted therapies that will lead to better treatment for this aggressive pediatric tumor.

  10. Modulation of K-ras-dependent lung tumorigenesis by microRNA-21

    Science.gov (United States)

    Hatley, Mark E.; Patrick, David M.; Garcia, Matthew R.; Richardson, James A.; Bassel-Duby, Rhonda; Van Rooij, Eva; Olson, Eric N.

    2010-01-01

    SUMMARY Lung cancer is the leading cause of cancer-related deaths in the world, and non-small cell lung cancer (NSCLC) accounts for 80% of cases. MicroRNA-21 (miR-21) expression is increased and predicts poor survival in NSCLC. Although miR-21 function has been studied in vitro using cancer cell lines, the role of miR-21 in tumor development in vivo is unknown. We utilize transgenic mice with loss-of-function and gain-of-function miR-21 alleles combined with a model of NSCLC to determine the role of miR-21 in lung cancer. We show that over-expression of miR-21 enhances tumorigenesis and genetic deletion of miR-21 partially protects against tumor formation. MiR-21 drives tumorigenesis through inhibition of negative regulators of the Ras/MEK/ERK pathway and inhibition of apoptosis. PMID:20832755

  11. Hyaline cartilage formation and tumorigenesis of implanted tissues derived from human induced pluripotent stem cells.

    Science.gov (United States)

    Saito, Taku; Yano, Fumiko; Mori, Daisuke; Kawata, Manabu; Hoshi, Kazuto; Takato, Tsuyoshi; Masaki, Hideki; Otsu, Makoto; Eto, Koji; Nakauchi, Hiromitsu; Chung, Ung-il; Tanaka, Sakae

    2015-01-01

    Induced pluripotent stem cells (iPSCs) are a promising cell source for cartilage regenerative medicine. Meanwhile, the risk of tumorigenesis should be considered in the clinical application of human iPSCs (hiPSCs). Here, we report in vitro chondrogenic differentiation of hiPSCs and maturation of the differentiated hiPSCs through transplantation into mouse knee joints. Three hiPSC clones showed efficient chondrogenic differentiation using an established protocol for human embryonic stem cells. The differentiated hiPSCs formed hyaline cartilage tissues at 8 weeks after transplantation into the articular cartilage of NOD/SCID mouse knee joints. Although tumors were not observed during the 8 weeks after transplantation, an immature teratoma had developed in one mouse at 16 weeks. In conclusion, hiPSCs are a potent cell source for regeneration of hyaline articular cartilage. However, the risk of tumorigenesis should be managed for clinical application in the future.

  12. STAT1 and STAT3 in tumorigenesis: A matter of balance.

    Science.gov (United States)

    Avalle, Lidia; Pensa, Sara; Regis, Gabriella; Novelli, Francesco; Poli, Valeria

    2012-04-01

    The transcription factors STAT1 and STAT3 appear to play opposite roles in tumorigenesis. While STAT3 promotes cell survival/proliferation, motility and immune tolerance and is considered as an oncogene, STAT1 mostly triggers anti-proliferative and pro-apoptotic responses while enhancing anti-tumor immunity. Despite being activated downstream of common cytokine and growth factor receptors, their activation is reciprocally regulated and perturbation in their balanced expression or phosphorylation levels may re-direct cytokine/growth factor signals from proliferative to apoptotic, or from inflammatory to anti-inflammatory. Here we review the functional canonical and non-canonical effects of STAT1 and STAT3 activation in tumorigenesis and their potential cross-regulation mechanisms.

  13. related chronic liver disease

    African Journals Online (AJOL)

    Yomi

    2012-03-08

    Mar 8, 2012 ... role in cell movement, apoptotic regulation, tumorigenesis regulation and ... All blood specimens were collected on an empty stomach and placed at room temperature for 20 min, then centrifuged for 20 min at 1,000 xg within ...

  14. Getting a New Liver: Facts about Liver Transplants

    Science.gov (United States)

    ... 2002 December 2006 March 2012 Getting A New Liver Facts About Liver Transplants American Society of Transplantation 1120 Route 73, ... views of the Society. _________________________________________________________________ 1 Getting a New Liver Facts About Liver Transplants A liver transplant is ...

  15. Enhancement of liver regeneration and liver surgery

    NARCIS (Netherlands)

    Olthof, P.B.

    2017-01-01

    Liver regeneration allows surgical resection of up to 75% of the liver and enables curative treatment potential for patients with primary or secondary hepatic malignancies. Liver surgery is associated with substantial risks, reflected by considerable morbidity and mortality rates. Optimization of

  16. Bmi1 promotes prostate tumorigenesis via inhibiting p16 and p14 expression

    OpenAIRE

    Fan, Catherine; He, Lizhi; Kapoor, Anil; Gillis, Aubrey; Rybak, Adrian P.; Cutz, Jean-Claude; Tang, Damu

    2008-01-01

    Bmi1 promotes prostate tumorigenesis via inhibiting p16INK4A and p14ARF expression correspondence: Corresponding authors. Anil Kapoor is to be contacted at Tel.: +1 (905) 522 1155, ext. 33218; fax: +1 (905) 521 6195. Damu Tang, T3310, St. Joseph?s Hospital, 50 Charlton Ave East, Hamilton, ON, Canada L8N 4A6. Tel.: +1 (905) 522 1155, ext. 35168; fax: +1 (905) 521 6181. (Kapoor, Anil) correspondence: Corresponding authors. Anil Ka...

  17. Overexpression of Sprouty 2 in Mouse Lung Epithelium Inhibits Urethane-Induced Tumorigenesis

    OpenAIRE

    Minowada, George; Miller, York E.

    2008-01-01

    Members of the Sprouty family encode novel proteins that are thought to function primarily as intracellular antagonists of the Ras-signaling pathway. Increased Ras signaling is a critical characteristic of human lung adenocarcinoma, the most common type of non–small cell lung cancer. Sprouty 2 is expressed in the lung epithelium, the tissue layer from which lung cancers arise. We hypothesized that overexpression of Sprouty 2 in the distal lung epithelium would inhibit lung tumorigenesis. To t...

  18. Multiple functions of DDX3 RNA helicase in gene regulation, tumorigenesis, and viral infection

    OpenAIRE

    2014-01-01

    The DEAD-box RNA helicase DDX3 is a multifunctional protein involved in all aspects of RNA metabolism, including transcription, splicing, mRNA nuclear export, translation, RNA decay and ribosome biogenesis. In addition, DDX3 is also implicated in cell cycle regulation, apoptosis, Wnt-β-catenin signaling, tumorigenesis, and viral infection. Notably, recent studies suggest that DDX3 is a component of anti-viral innate immune signaling pathways. Indeed, DDX3 contributes to enhance the induction ...

  19. Interleukin-6 mediates epithelial-stromal interactions and promotes gastric tumorigenesis.

    Directory of Open Access Journals (Sweden)

    Hiroto Kinoshita

    Full Text Available Interleukin-6 (IL-6 is a pleiotropic cytokine that affects various functions, including tumor development. Although the importance of IL-6 in gastric cancer has been documented in experimental and clinical studies, the mechanism by which IL-6 promotes gastric cancer remains unclear. In this study, we investigated the role of IL-6 in the epithelial-stromal interaction in gastric tumorigenesis. Immunohistochemical analysis of human gastritis, gastric adenoma, and gastric cancer tissues revealed that IL-6 was frequently detected in the stroma. IL-6-positive cells in the stroma showed positive staining for the fibroblast marker α-smooth muscle actin, suggesting that stromal fibroblasts produce IL-6. We compared IL-6 knockout (IL-6(-/- mice with wild-type (WT mice in a model of gastric tumorigenesis induced by the chemical carcinogen N-methyl-N-nitrosourea. The stromal fibroblasts expressed IL-6 in tumors from WT mice. Gastric tumorigenesis was attenuated in IL-6(-/- mice, compared with WT mice. Impaired tumor development in IL-6(-/- mice was correlated with the decreased activation of STAT3, a factor associated with gastric cancer cell proliferation. In vitro, when gastric cancer cell line was co-cultured with primary human gastric fibroblast, STAT3-related genes including COX-2 and iNOS were induced in gastric cancer cells and this response was attenuated with neutralizing anti-IL-6 receptor antibody. IL-6 production from fibroblasts was increased when fibroblasts were cultured in the presence of gastric cancer cell-conditioned media. IL-6 production from fibroblasts was suppressed by an interleukin-1 (IL-1 receptor antagonist and siRNA inhibition of IL-1α in the fibroblasts. IL-1α mRNA and protein were increased in fibroblast lysate, suggesting that cell-associated IL-1α in fibroblasts may be involved. Our results suggest the importance of IL-6 mediated stromal-epithelial cell interaction in gastric tumorigenesis.

  20. Hypomethylation of Long Interspersed Nuclear Element-1 is Involved in the Early Tumorigenesis of Hepatocellular Carcinoma

    Directory of Open Access Journals (Sweden)

    Wenhua Piao

    2014-08-01

    high FAL group. No associations between the level of hypomethylation of LINE-1 and HBV infection, age, sex, and cirrhosis were found. Conclusions: These results are strongly suggested that the hypomethylation of LINE-1 plays a role in the hepatocarcinogenesis; moreover, the hypomethylation of LINE-1 occurs not only in the progression of HCC, but also in the early stage of HCC tumorigenesis. [J Interdiscipl Histopathol 2014; 2(4.000: 191-196

  1. Role of the Rb and p53 Tumor Suppressor Pathways in Mammary Tumorigenesis

    Science.gov (United States)

    2012-09-01

    kinase screen and off-patent drug screen) REPORTABLE OUTCOMES Jones, Robert., Jiang, Zhe ., Deng, Tao., Schimmer, AD., Moffat, J and...Robert., Jiang, Zhe ., Deng, Tao., Schimmer, AD., Moffat, J and Zacksenhaus, E. Role of the RB and p53 tumor suppressor pathways in mammary tumorigenesis...CDMRP 2011 Era of Hope Conference Jiang Z, Jones R, Liu JC, Deng T, Robinson T, Chung PE, Wang S, Herschkowitz Jl, Egan SE, Perou CM

  2. Chemoprevention of intestinal tumorigenesis by nabumetone: induction of apoptosis and Bcl-2 downregulation

    OpenAIRE

    Roy, H K; Karoski, W J; Ratashak, A; Smyrk, T. C.

    2001-01-01

    Treatment of MIN mice with the nonsteroidal anti-inflammatory drug, nabumetone, resulted in a dose-dependent suppression of intestinal tumorigenesis. In both the uninvolved MIN mouse colonic epithelium and HT-29 colon cancer cells, nabumetone downregulated the anti-apoptotic protein, Bcl-2, with concomitant induction of apoptosis, suggesting a potential mechanism for colon cancer chemoprevention. © 2001 Cancer Research Campaign www.bjcancer.com

  3. CCR6, the sole receptor for the chemokine CCL20, promotes spontaneous intestinal tumorigenesis.

    Directory of Open Access Journals (Sweden)

    Bisweswar Nandi

    Full Text Available Interactions between the inflammatory chemokine CCL20 and its receptor CCR6 have been associated with colorectal cancer growth and metastasis, however, a causal role for CCL20 signaling through CCR6 in promoting intestinal carcinogenesis has not been demonstrated in vivo. In this study, we aimed to determine the role of CCL20-CCR6 interactions in spontaneous intestinal tumorigenesis. CCR6-deficient mice were crossed with mice heterozygous for a mutation in the adenomatous polyposis coli (APC gene (APCMIN/+ mice to generate APCMIN/+ mice with CCR6 knocked out (CCR6KO-APCMIN/+ mice. CCR6KO-APCMIN/+ mice had diminished spontaneous intestinal tumorigenesis. CCR6KO-APCMIN/+ also had normal sized spleens as compared to the enlarged spleens found in APCMIN/+ mice. Decreased macrophage infiltration into intestinal adenomas and non-tumor epithelium was observed in CCR6KO-APCMIN/+ as compared to APCMIN/+ mice. CCL20 signaling through CCR6 caused increased production of CCL20 by colorectal cancer cell lines. Furthermore, CCL20 had a direct mitogenic effect on colorectal cancer cells. Thus, interactions between CCL20 and CCR6 promote intestinal carcinogenesis. Our results suggest that the intestinal tumorigenesis driven by CCL20-CCR6 interactions may be driven by macrophage recruitment into the intestine as well as proliferation of neoplastic epithelial cells. This interaction could be targeted for the treatment or prevention of malignancy.

  4. Miz1 is a critical repressor of cdkn1a during skin tumorigenesis.

    Directory of Open Access Journals (Sweden)

    Jan Hönnemann

    Full Text Available The transcription factor Miz1 forms repressive DNA-binding complexes with the Myc, Gfi-1 and Bcl-6 oncoproteins. Known target genes of these complexes encode the cyclin-dependent kinase inhibitors (CKIs cdkn2b (p15(Ink4, cdkn1a (p21(Cip1, and cdkn1c (p57(Kip2. Whether Miz1-mediated repression is important for control of cell proliferation in vivo and for tumor formation is unknown. Here we show that deletion of the Miz1 POZ domain, which is critical for Miz1 function, restrains the development of skin tumors in a model of chemically-induced, Ras-dependent tumorigenesis. While the stem cell compartment appears unaffected, interfollicular keratinocytes lacking functional Miz1 exhibit a reduced proliferation and an accelerated differentiation of the epidermis in response to the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA. Tumorigenesis, proliferation and normal differentiation are restored in animals lacking cdkn1a, but not in those lacking cdkn2b. Our data demonstrate that Miz1-mediated attenuation of cell cycle arrest pathways via repression of cdkn1a has a critical role during tumorigenesis in the skin.

  5. Redundant Innate and Adaptive Sources of IL17 Production Drive Colon Tumorigenesis.

    Science.gov (United States)

    Housseau, Franck; Wu, Shaoguang; Wick, Elizabeth C; Fan, Hongni; Wu, Xinqun; Llosa, Nicolas J; Smith, Kellie N; Tam, Ada; Ganguly, Sudipto; Wanyiri, Jane W; Iyadorai, Thevambiga; Malik, Ausama A; Roslani, April C; Vadivelu, Jamunarani S; Van Meerbeke, Sara; Huso, David L; Pardoll, Drew M; Sears, Cynthia L

    2016-04-15

    IL17-producing Th17 cells, generated through a STAT3-dependent mechanism, have been shown to promote carcinogenesis in many systems, including microbe-driven colon cancer. Additional sources of IL17, such as γδ T cells, become available under inflammatory conditions, but their contributions to cancer development are unclear. In this study, we modeled Th17-driven colon tumorigenesis by colonizing Min(Ap) (c+/-) mice with the human gut bacterium, enterotoxigenic Bacteroides fragilis (ETBF), to investigate the link between inflammation and colorectal cancer. We found that ablating Th17 cells by knocking out Stat3 in CD4(+) T cells delayed tumorigenesis, but failed to suppress the eventual formation of colonic tumors. However, IL17 blockade significantly attenuated tumor formation, indicating a critical requirement for IL17 in tumorigenesis, but from a source other than Th17 cells. Notably, genetic ablation of γδ T cells in ETBF-colonized Th17-deficient Min mice prevented the late emergence of colonic tumors. Taken together, these findings support a redundant role for adaptive Th17 cell- and innate γδT17 cell-derived IL17 in bacteria-induced colon carcinogenesis, stressing the importance of therapeutically targeting the cytokine itself rather than its cellular sources. Cancer Res; 76(8); 2115-24. ©2016 AACR.

  6. Extra sex combs, chromatin, and cancer: Exploring epigenetic regulation and tumorigenesis in Drosophila

    Institute of Scientific and Technical Information of China (English)

    Can Zhang; Bo Liu; Guangyao Li; Lei Zhou

    2011-01-01

    Developmental genetic studies in Drosophila unraveled the importance of Polycomb group (PcG) and Trithorax group (TrxG) genes in controlling cellular identity.PcG and TrxG proteins form histone modifying complexes that catalyze repressive or activating histone modifications,respectively,and thus maintaining the expression status of homeotic genes.Human orthologs of PcG and TrxG genes are implicated in tumorigenesis as well as in determining the prognosis of individual cancers.Recent whole genome analyses of cancers also highlighted the importance of histone modifying proteins in controlling tumorigenesis.Comprehensive understanding of the mechanistic relationship between histone regulation and tumorigenesis holds the promise of significantly advancing our understanding and management of cancer.It is anticipated that Drosophila melanogaster,the model organism that contributed significantly to our understanding of the functional role of histone regulation in development,could also provide unique insight for our understanding of how histone dysregulation can lead to cancer.In this review,we will discuss several recent advances in this regard.

  7. MicroRNA-31 initiates lung tumorigenesis and promotes mutant KRAS-driven lung cancer.

    Science.gov (United States)

    Edmonds, Mick D; Boyd, Kelli L; Moyo, Tamara; Mitra, Ramkrishna; Duszynski, Robert; Arrate, Maria Pia; Chen, Xi; Zhao, Zhongming; Blackwell, Timothy S; Andl, Thomas; Eischen, Christine M

    2016-01-01

    MicroRNA (miR) are important regulators of gene expression, and aberrant miR expression has been linked to oncogenesis; however, little is understood about their contribution to lung tumorigenesis. Here, we determined that miR-31 is overexpressed in human lung adenocarcinoma and this overexpression independently correlates with decreased patient survival. We developed a transgenic mouse model that allows for lung-specific expression of miR-31 to test the oncogenic potential of miR-31 in the lung. Using this model, we observed that miR-31 induction results in lung hyperplasia, followed by adenoma formation and later adenocarcinoma development. Moreover, induced expression of miR-31 in mice cooperated with mutant KRAS to accelerate lung tumorigenesis. We determined that miR-31 regulates lung epithelial cell growth and identified 6 negative regulators of RAS/MAPK signaling as direct targets of miR-31. Our study distinguishes miR-31 as a driver of lung tumorigenesis that promotes mutant KRAS-mediated oncogenesis and reveals that miR-31 directly targets and reduces expression of negative regulators of RAS/MAPK signaling.

  8. Mechanisms of increased risk of tumorigenesis in Atm and Brca1 double heterozygosity

    Directory of Open Access Journals (Sweden)

    Wang Jufang

    2011-08-01

    Full Text Available Abstract Background Both epidemiological and experimental studies suggest that heterozygosity for a single gene is linked with tumorigenesis and heterozygosity for two genes increases the risk of tumor incidence. Our previous work has demonstrated that Atm/Brca1 double heterozygosity leads to higher cell transformation rate than single heterozygosity. However, the underlying mechanisms have not been fully understood yet. In the present study, a series of pathways were investigated to clarify the possible mechanisms of increased risk of tumorigenesis in Atm and Brca1 heterozygosity. Methods Wild type cells, Atm or Brca1 single heterozygous cells, and Atm/Brca1 double heterozygous cells were used to investigate DNA damage and repair, cell cycle, micronuclei, and cell transformation after photon irradiation. Results Remarkable high transformation frequency was confirmed in Atm/Brca1 double heterozygous cells compared to wild type cells. It was observed that delayed DNA damage recognition, disturbed cell cycle checkpoint, incomplete DNA repair, and increased genomic instability were involved in the biological networks. Haploinsufficiency of either ATM or BRCA1 negatively impacts these pathways. Conclusions The quantity of critical proteins such as ATM and BRCA1 plays an important role in determination of the fate of cells exposed to ionizing radiation and double heterozygosity increases the risk of tumorigenesis. These findings also benefit understanding of the individual susceptibility to tumor initiation.

  9. Liver cirrhosis and fatty liver

    Institute of Scientific and Technical Information of China (English)

    1993-01-01

    930537 Preliminary report on portal hyperten-tion in liver cirrhosis treated by transjugular in-trahepatic portosystemic stent shunt(analysis of8 cases).XU Ke(徐克),et al.Dept Radiol,lst Hosp,China Med Univ,Shenyang,110001.Chin J Radiol 1993;25(5):294—297.Transjugular intrahepatic portosystemic stentshunt(TIPPS)was performed in 8 cases of livercirrhosis with portal hypertention.Moderate orsevere hemorrhage from gastroesophageal variceshad happened in all patients for 2~5 times beforTIPSS.The average pressure of portal veindropped from 3.80±0.50kPa to 2.58±0.26kPa.The diameter of the shunt established be-tween portal and hepatic veins was 10~12mm.Gastrointestinal bleeding and ascites were effec-

  10. Role of liver progenitors in liver regeneration.

    Science.gov (United States)

    Best, Jan; Manka, Paul; Syn, Wing-Kin; Dollé, Laurent; van Grunsven, Leo A; Canbay, Ali

    2015-02-01

    During massive liver injury and hepatocyte loss, the intrinsic regenerative capacity of the liver by replication of resident hepatocytes is overwhelmed. Treatment of this condition depends on the cause of liver injury, though in many cases liver transplantation (LT) remains the only curative option. LT for end stage chronic and acute liver diseases is hampered by shortage of donor organs and requires immunosuppression. Hepatocyte transplantation is limited by yet unresolved technical difficulties. Since currently no treatment is available to facilitate liver regeneration directly, therapies involving the use of resident liver stem or progenitor cells (LPCs) or non-liver stem cells are coming to fore. LPCs are quiescent in the healthy liver, but may be activated under conditions where the regenerative capacity of mature hepatocytes is severely impaired. Non-liver stem cells include embryonic stem cells (ES cells) and mesenchymal stem cells (MSCs). In the first section, we aim to provide an overview of the role of putative cytokines, growth factors, mitogens and hormones in regulating LPC response and briefly discuss the prognostic value of the LPC response in clinical practice. In the latter section, we will highlight the role of other (non-liver) stem cells in transplantation and discuss advantages and disadvantages of ES cells, induced pluripotent stem cells (iPS), as well as MSCs.

  11. Immune mediated liver failure

    OpenAIRE

    Wang, Xiaojing; Ning, Qin

    2014-01-01

    Liver failure is a clinical syndrome of various etiologies, manifesting as jaundice, encephalopathy, coagulopathy and circulatory dysfunction, which result in subsequent multiorgan failure. Clinically, liver failure is classified into four categories: acute, subacute, acute-on-chronic and chronic liver failure. Massive hepatocyte death is considered to be the core event in the development of liver failure, which occurs when the extent of hepatocyte death is beyond the liver regenerative capac...

  12. Appropriateness of Liver Biopsy

    OpenAIRE

    Thierry Poynard; Vlad Ratziu; Pierre Bedossa

    2000-01-01

    This review aims to discuss the appropriateness of liver biopsy in two frequent liver diseases, hepatitis C and alcoholic liver disease. The medical literature, published between 1965 and 1999, was reviewed by using MEDLINE. Only 0.1% of the publications were devoted specifically to the appropriateness of liver biopsy. Not all studies observed a significant agreement among doctors on the decision to use liver biopsy. Therefore, there is a possibility that hepatologists have significant, heter...

  13. Obesity, fatty liver and liver cancer.

    Science.gov (United States)

    Qian, Yan; Fan, Jian-Gao

    2005-05-01

    It has been suggested that obesity and fatty liver may be associated with the morbidity and mortality of liver cancer, and the early diagnosis and effective treatment of fatty liver coupled with liver cancer are supposed to improve the prognosis of obese patients. This review was attempted to understand the relationship between obesity, fatty liver and liver cancer. An English-language literature search using PUBMED (1990-2004) on obesity, fatty liver and liver cancer and other related articles in Chinese. Obesity is associated with the risk of death from all cancers and from cancers at individual sites including liver cancer, and it is an independent risk factor for hepatocellular carcinoma (HCC) in patients with alcoholic cirrhosis and cryptogenic cirrhosis. Because nonalcoholic steatohepatitis has been implicated as a major cause of cryptogenic cirrhosis, the development of HCC may be part of progressive nature of this condition. Obesity is associated with the incidence and mortality of HCC. More frequent surveillance for HCC may be warranted in obese patients with fatty liver and attempts should be made to interrupt the progression from simple hepatic steatosis to steatohepatitis, cirrhosis and ultimately HCC.

  14. SIGNIFICANCE AND CORRELATION OF MAPK/ERK2 AND PI3-K IN HUMAN BREAST TUMORIGENESIS

    Institute of Scientific and Technical Information of China (English)

    MA Ping; LI Bai-lin; ZHANG Ying; SONG Min; SONG Ji-ye

    2006-01-01

    Objective: MAPK ((Mitogen-actived Protein Kinase) and PI3-K (Phosphatidylinositol 3-kinase) pathways have been implicated in the mitogenic pathways regulating cell growth, proliferation, differentiation and transformation and thus involved in tumorigenesis. This study was designed to examined the protein expression, activity and mRNA levels of both ERK and PI3-K in a series of breast tumors and adjacent mammary glands, and to figure out the changes of ERK2 and PI3-K during the dynamic process of breast tumorigenesis. Methods: A series of breast tumors and adjacent mammary glands were collected at surgery, including 37 cases of breast cancer, 6 cases of atypical hyperplasia-breast carcinoma in situ and 15 cases of benign conditions. Western blot, kinase activity assay and RT-PCR were used to detect the protein expression, kinase activity and mRNA level, respectively. Results: The revels of protein, activity and mRNA of ERK2 were elevated during the stages of both initiation and progression. The increasing tendency in breast cancer was equal to atypical hyperplasia -in situ carcinoma, but higher than in benign lesion and adjacent normal mammary gland. PI3-K was activated during the stage of progression of breast cancer. An inverse correlation between the activity of PI3-K and ERK2 in breast cancer was found. Conclusion: Our findings indicate that ERK2 may perform its function during both the stages of breast cancer initiation and breast cancer progression, while PI3-K may exert its effect during the stage of breast cancer progression. Both PI3-k and ERK2 are involved in the tumorigenesis of breast cancer.

  15. Evaluation of Rint1 as a modifier of intestinal tumorigenesis and cancer risk

    Science.gov (United States)

    Otterpohl, Karla L.; Gould, Karen A.

    2017-01-01

    The Rad50 Interacting Protein 1 (Rint1) influences cellular homeostasis through maintenance of endoplasmic reticulum, Golgi and centrosome integrity and regulation of vesicle transport, autophagy and the G2/M checkpoint. Rint1 has been postulated to function as a tumor suppressor as well as an oncogene, with its role depending perhaps upon the precise cellular and/or experimental context. In humans, heterozygosity for germline missense variants in RINT1 have, in some studies, been associated with increased risk of both breast and Lynch syndrome type cancers. However, it is not known if these germline variants represent loss of function alleles or gain of function alleles. Based upon these findings, as well as our initial consideration of Rint1 as a potential candidate for Mom5, a genetic modifier of intestinal tumorigenesis in ApcMin/+ mice, we sought to explicitly examine the impact of Rint1 on tumorigenesis in ApcMin/+ mice. However, heterozygosity for a knockout of Rint1 had no impact on tumorigenesis in Rint1+/-; ApcMin/+ mice. Likewise, we found no evidence to suggest that the remaining Rint1 allele was lost somatically in intestinal tumors in ApcMin/+ mice. Interestingly, in contrast to what has been observed in Rint1+/- mice on a mixed genetic background, Rint1+/- mice on a pure C57BL/6J background did not show spontaneous tumor development. We also evaluated colorectal cancer data available in the COSMIC and ONCOMINE databases and found that RINT1 overexpression, as well as the presence of somatic missense mutations in RINT1 were associated with colorectal cancer development. In vitro evaluation of two missense variants in RINT1 suggested that such variants do have the potential to impact RINT1 function. PMID:28264000

  16. Oral administration of aflatoxin G₁ induces chronic alveolar inflammation associated with lung tumorigenesis.

    Science.gov (United States)

    Liu, Chunping; Shen, Haitao; Yi, Li; Shao, Peilu; Soulika, Athena M; Meng, Xinxing; Xing, Lingxiao; Yan, Xia; Zhang, Xianghong

    2015-02-03

    Our previous studies showed oral gavage of aflatoxin G₁ (AFG₁) induced lung adenocarcinoma in NIH mice. We recently found that a single intratracheal administration of AFG₁ caused chronic inflammatory changes in rat alveolar septum. Here, we examine whether oral gavage of AFG₁ induces chronic lung inflammation and how it contributes to carcinogenesis. We evaluated chronic lung inflammatory responses in Balb/c mice after oral gavage of AFG₁ for 1, 3 and 6 months. Inflammatory responses were heightened in the lung alveolar septum, 3 and 6 months after AFG₁ treatment, evidenced by increased macrophages and lymphocytes infiltration, up-regulation of NF-κB and p-STAT3, and cytokines production. High expression levels of superoxide dismutase (SOD-2) and hemoxygenase-1 (HO-1), two established markers of oxidative stress, were detected in alveolar epithelium of AFG₁-treated mice. Promoted alveolar type II cell (AT-II) proliferation in alveolar epithelium and angiogenesis, as well as increased COX-2 expression were also observed in lung tissues of AFG₁-treated mice. Furthermore, we prolonged survival of the mice in the above model for another 6 months to examine the contribution of AFG₁-induced chronic inflammation to lung tumorigenesis. Twelve months later, we observed that AFG₁ induced alveolar epithelial hyperplasia and adenocarcinoma in Balb/c mice. Up-regulation of NF-κB, p-STAT3, and COX-2 was also induced in lung adenocarcinoma, thus establishing a link between AFG₁-induced chronic inflammation and lung tumorigenesis. This is the first study to show that oral administration of AFG₁ could induce chronic lung inflammation, which may provide a pro-tumor microenvironment to contribute to lung tumorigenesis.

  17. Obesity does not promote tumorigenesis of localized patient-derived prostate cancer xenografts

    Science.gov (United States)

    Ascui, Natasha; Frydenberg, Mark; Risbridger, Gail P.; Taylor, Renea A.; Watt, Matthew J.

    2016-01-01

    There are established epidemiological links between obesity and the severity of prostate cancer. We directly tested this relationship by assessing tumorigenicity of patient-derived xenografts (PDXs) of moderate-grade localized prostate cancer in lean and obese severe combined immunodeficiency (SCID) mice. Mice were rendered obese and insulin resistant by high-fat feeding for 6 weeks prior to transplantation, and PDXs were assessed 10 weeks thereafter. Histological analysis of PDX grafts showed no differences in tumor pathology, prostate-specific antigen, androgen receptor and homeobox protein Nkx-3.1 expression, or proliferation index in lean versus obese mice. Whilst systemic obesity per se did not promote prostate tumorigenicity, we next asked whether the peri-prostatic adipose tissue (PPAT), which covers the prostate anteriorly, plays a role in prostate tumorigenesis. In vitro studies in a cellularized co-culture model of stromal and epithelial cells demonstrated that factors secreted from human PPAT are pro-tumorigenic. Accordingly, we recapitulated the prostate-PPAT spatial relationship by co-grafting human PPAT with prostate cancer in PDX grafts. PDX tissues were harvested 10 weeks after grafting, and histological analysis revealed no evidence of enhanced tumorigenesis with PPAT compared to prostate cancer grafts alone. Altogether, these data demonstrate that prostate cancer tumorigenicity is not accelerated in the setting of diet-induced obesity or in the presence of human PPAT, prompting the need for further work to define the at-risk populations of obesity-driven tumorigenesis and the biological factors linking obesity, adipose tissue and prostate cancer pathogenesis. PMID:27351281

  18. Obesity does not promote tumorigenesis of localized patient-derived prostate cancer xenografts.

    Science.gov (United States)

    Lo, Jennifer C Y; Clark, Ashlee K; Ascui, Natasha; Frydenberg, Mark; Risbridger, Gail P; Taylor, Renea A; Watt, Matthew J

    2016-07-26

    There are established epidemiological links between obesity and the severity of prostate cancer. We directly tested this relationship by assessing tumorigenicity of patient-derived xenografts (PDXs) of moderate-grade localized prostate cancer in lean and obese severe combined immunodeficiency (SCID) mice. Mice were rendered obese and insulin resistant by high-fat feeding for 6 weeks prior to transplantation, and PDXs were assessed 10 weeks thereafter. Histological analysis of PDX grafts showed no differences in tumor pathology, prostate-specific antigen, androgen receptor and homeobox protein Nkx-3.1 expression, or proliferation index in lean versus obese mice. Whilst systemic obesity per se did not promote prostate tumorigenicity, we next asked whether the peri-prostatic adipose tissue (PPAT), which covers the prostate anteriorly, plays a role in prostate tumorigenesis. In vitro studies in a cellularized co-culture model of stromal and epithelial cells demonstrated that factors secreted from human PPAT are pro-tumorigenic. Accordingly, we recapitulated the prostate-PPAT spatial relationship by co-grafting human PPAT with prostate cancer in PDX grafts. PDX tissues were harvested 10 weeks after grafting, and histological analysis revealed no evidence of enhanced tumorigenesis with PPAT compared to prostate cancer grafts alone. Altogether, these data demonstrate that prostate cancer tumorigenicity is not accelerated in the setting of diet-induced obesity or in the presence of human PPAT, prompting the need for further work to define the at-risk populations of obesity-driven tumorigenesis and the biological factors linking obesity, adipose tissue and prostate cancer pathogenesis.

  19. Activation-Induced Cytidine Deaminase Contributes to Pancreatic Tumorigenesis by Inducing Tumor-Related Gene Mutations.

    Science.gov (United States)

    Sawai, Yugo; Kodama, Yuzo; Shimizu, Takahiro; Ota, Yuji; Maruno, Takahisa; Eso, Yuji; Kurita, Akira; Shiokawa, Masahiro; Tsuji, Yoshihisa; Uza, Norimitsu; Matsumoto, Yuko; Masui, Toshihiko; Uemoto, Shinji; Marusawa, Hiroyuki; Chiba, Tsutomu

    2015-08-15

    Pancreatic ductal adenocarcinoma (PDAC) develops via an accumulation of various gene mutations. The mechanism underlying the mutations in PDAC development, however, is not fully understood. Recent insight into the close association between the mutation pattern of various cancers and specific mutagens led us to investigate the possible involvement of activation-induced cytidine deaminase (AID), a DNA editing enzyme, in pancreatic tumorigenesis. Our immunohistochemical findings revealed AID protein expression in human acinar ductal metaplasia, pancreatic intraepithelial neoplasia, and PDAC. Both the amount and intensity of the AID protein expression increased with the progression from precancerous to cancerous lesions in human PDAC tissues. To further assess the significance of ectopic epithelial AID expression in pancreatic tumorigenesis, we analyzed the phenotype of AID transgenic (AID Tg) mice. Consistent with our hypothesis that AID is involved in the mechanism of the mutations underlying pancreatic tumorigenesis, we found precancerous lesions developing in the pancreas of AID Tg mice. Using deep sequencing, we also detected Kras and c-Myc mutations in our analysis of the whole pancreas of AID Tg mice. In addition, Sanger sequencing confirmed the presence of Kras, c-Myc, and Smad4 mutations, with the typical mutational footprint of AID in precancerous lesions in AID Tg mice separated by laser capture microdissection. Taken together, our findings suggest that AID contributes to the development of pancreatic precancerous lesions by inducing tumor-related gene mutations. Our new mouse model without intentional manipulation of specific tumor-related genes provides a powerful system for analyzing the mutations involved in PDAC.

  20. PTBP1-dependent regulation of USP5 alternative RNA splicing plays a role in glioblastoma tumorigenesis.

    Science.gov (United States)

    Izaguirre, Daisy I; Zhu, Wen; Hai, Tao; Cheung, Hannah C; Krahe, Ralf; Cote, Gilbert J

    2012-11-01

    Aberrant RNA splicing is thought to play a key role in tumorigenesis. The assessment of its specific contributions is limited by the complexity of information derived from genome-wide array-based approaches. We describe how performing splicing factor-specific comparisons using both tumor and cell line data sets may more readily identify physiologically relevant tumor-specific splicing events. Affymetrix exon array data derived from glioblastoma (GBM) tumor samples with defined polypyrimidine tract-binding protein 1 (PTBP1) levels were compared with data from U251 GBM cells with and without PTBP1 knockdown. This comparison yielded overlapping gene sets that comprised only a minor fraction of each data set. The identification of a novel GBM-specific splicing event involving the USP5 gene led us to further examine its role in tumorigenesis. In GBM, USP5 generates a shorter isoform 2 through recognition of a 5' splice site within exon 15. Production of the USP5 isoform 2 was strongly correlated with PTBP1 expression in GBM tumor samples and cell lines. Splicing regulation was consistent with the presence of an intronic PTBP1 binding site and could be modulated through antisense targeting of the isoform 2 splice site to force expression of isoform 1 in GBM cells. The forced expression of USP5 isoform 1 in two GBM cell lines inhibited cell growth and migration, implying an important role for USP5 splicing in gliomagenesis. These results support a role for aberrant RNA splicing in tumorigenesis and suggest that changes in relatively few genes may be sufficient to drive the process.

  1. Biomarkers for liver fibrosis

    Science.gov (United States)

    Jacobs, Jon M.; Burnum-Johnson, Kristin E.; Baker, Erin M.; Smith, Richard D.; Gritsenko, Marina A.; Orton, Daniel

    2015-09-15

    Methods and systems for diagnosing or prognosing liver fibrosis in a subject are provided. In some examples, such methods and systems can include detecting liver fibrosis-related molecules in a sample obtained from the subject, comparing expression of the molecules in the sample to controls representing expression values expected in a subject who does not have liver fibrosis or who has non-progressing fibrosis, and diagnosing or prognosing liver fibrosis in the subject when differential expression of the molecules between the sample and the controls is detected. Kits for the diagnosis or prognosis of liver fibrosis in a subject are also provided which include reagents for detecting liver fibrosis related molecules.

  2. Biomarkers for liver fibrosis

    Energy Technology Data Exchange (ETDEWEB)

    Jacobs, Jon M.; Burnum-Johnson, Kristin E.; Baker, Erin M.; Smith, Richard D.; Gritsenko, Marina A.; Orton, Daniel

    2017-05-16

    Methods and systems for diagnosing or prognosing liver fibrosis in a subject are provided. In some examples, such methods and systems can include detecting liver fibrosis-related molecules in a sample obtained from the subject, comparing expression of the molecules in the sample to controls representing expression values expected in a subject who does not have liver fibrosis or who has non-progressing fibrosis, and diagnosing or prognosing liver fibrosis in the subject when differential expression of the molecules between the sample and the controls is detected. Kits for the diagnosis or prognosis of liver fibrosis in a subject are also provided which include reagents for detecting liver fibrosis related molecules.

  3. Co-infection ofEpstein-Barr virus andhuman papillomavirus inhuman tumorigenesis

    Institute of Scientific and Technical Information of China (English)

    YingShi; SongLingPeng; LiFangYang; XueChen; YongGuangTao; YaCao

    2016-01-01

    Viral infections contribute to approximately 12% of cancers worldwide, with the vast majority occurring in developing countries and areas. Two DNA viruses, Epstein‑Barr virus (EBV) and human papillomavirus (HPV), are associated with 38% of all virus‑associated cancers. The probability of one patient infected with these two distinct types of viruses is increasing. Here, we summarize the co‑infection of EBV and HPV in human malignancies and address the possible mechanisms for the co‑infection of EBV and HPV during tumorigenesis.

  4. MicroRNA in Metabolic Re-Programming and Their Role in Tumorigenesis

    Science.gov (United States)

    Tomasetti, Marco; Amati, Monica; Santarelli, Lory; Neuzil, Jiri

    2016-01-01

    The process of metabolic re-programing is linked to the activation of oncogenes and/or suppression of tumour suppressor genes, which are regulated by microRNAs (miRNAs). The interplay between oncogenic transformation-driven metabolic re-programming and modulation of aberrant miRNAs further established their critical role in the initiation, promotion and progression of cancer by creating a tumorigenesis-prone microenvironment, thus orchestrating processes of evasion to apoptosis, angiogenesis and invasion/migration, as well metastasis. Given the involvement of miRNAs in tumour development and their global deregulation, they may be perceived as biomarkers in cancer of therapeutic relevance. PMID:27213336

  5. The glucose transporter GLUT1 is required for ErbB2-induced mammary tumorigenesis.

    Science.gov (United States)

    Wellberg, Elizabeth A; Johnson, Stevi; Finlay-Schultz, Jessica; Lewis, Andrew S; Terrell, Kristina L; Sartorius, Carol A; Abel, E Dale; Muller, William J; Anderson, Steven M

    2016-12-20

    Altered tumor cell metabolism is an emerging hallmark of cancer; however, the precise role for glucose in tumor initiation is not known. GLUT1 (SLC2A1) is expressed in breast cancer cells and is likely responsible for avid glucose uptake observed in established tumors. We have shown that GLUT1 was necessary for xenograft tumor formation from primary mammary cells transformed with the polyomavirus middle-T antigen but that it was not necessary for growth after tumors had formed in vivo, suggesting a differential requirement for glucose depending on the stage of tumorigenesis. To determine whether GLUT1 is required early during mammary tumorigenesis, we crossed MMTV-NIC mice, which express activated HER2/NEU/ERBB2 and Cre recombinase, to Slc2a1 (Flox/Flox) (GLUT1(Flox/Flox)) mice to generate NIC-GLUT1(+/+), NIC-GLUT1(Flox/+), and NIC-GLUT1(Flox/Flox) mice. In addition, we evaluated effects of glucose restriction or GLUT1 inhibition on transformation in MCF10A-ERBB2 breast epithelial cells in three-dimensional culture. Finally, we utilized global gene expression profiling data of primary human breast tumors to determine the relationship between SLC2A1 and stage of tumorigenesis. All of the NIC-GLUT1(+/+) mice developed tumors in less than 200 days. In contrast, only 1 NIC-GLUT1(Flox/Flox) mouse and 1 NIC-GLUT1(Flox/+) mouse developed mammary tumors, even after 18 months. Mammary gland development was not disrupted in NIC mice lacking GLUT1; however, epithelial content of mature glands was reduced compared to NIC-GLUT1(Flox/+) mice. In MCF10A-ERBB2 cells, glucose restriction or GLUT1 inhibition blocked transformation induced by activated ERBB2 through reduced cell proliferation. In human breast cancers, SLC2A1 was higher in ductal carcinoma in situ compared to the normal breast, but lower in invasive versus in situ lesions, suggesting the requirement for GLUT1 decreases as tumors progress. This study demonstrates a strict requirement for GLUT1 in the early stages of

  6. HMGA2 induces pituitary tumorigenesis by enhancing E2F1 activity

    DEFF Research Database (Denmark)

    Fedele, Monica; Visone, Rosa; De Martino, Ivana

    2006-01-01

    HMGA2 gene amplification and overexpression in human prolactinomas and the development of pituitary adenomas in HMGA2 transgenic mice showed that HMGA2 plays a crucial role in pituitary tumorigenesis. We have explored the pRB/E2F1 pathway to investigate the mechanism by which HMGA2 acts. Here we......2 mice. Thus, HMGA2-mediated E2F1 activation is a crucial event in the onset of these tumors in transgenic mice and probably also in human prolactinomas....

  7. The Role of Skp2 in the Prostate Tumorigenesis Following Rb and p53 Loss

    Science.gov (United States)

    2015-12-01

    9 mM NaCl, 40 mM citric acid /sodium phosphate buffer pH6.0, and 1 mg/ml X-gal) for 16 hr (MEFs) and 5 hr (human cancer cell lines) at 37C...2012). Activated p53 switches on its target genes to induce cell- cycle arrest, senescence, and apoptosis to safe- guard against tumorigenesis. In...blot analysis. The cyclin A protein level is shown to indicate cell- cycle progression, and the tubulin level is shown to indicate loading amounts. FBS

  8. Bioartificial liver: current status.

    Science.gov (United States)

    Pless, G; Sauer, I M

    2005-11-01

    Liver failure remains a life-threatening syndrome. With the growing disparity between the number of suitable donor organs and the number of patients awaiting transplantation, efforts have been made to optimize the allocation of organs, to find alternatives to cadaveric liver transplantation, and to develop extracorporeal methods to support or replace the function of the failing organ. An extracorporeal liver support system has to provide the main functions of the liver: detoxification, synthesis, and regulation. The understanding that the critical issue of the clinical syndrome in liver failure is the accumulation of toxins not cleared by the failing liver led to the development of artificial filtration and adsorption devices (artificial liver support). Based on this hypothesis, the removal of lipophilic, albumin-bound substances, such as bilirubin, bile acids, metabolites of aromatic amino acids, medium-chain fatty acids, and cytokines, should be beneficial to the clinical course of a patient in liver failure. Artificial detoxification devices currently under clinical evaluation include the Molecular Adsorbent Recirculating System (MARS), Single-Pass Albumin Dialysis (SPAD), and the Prometheus system. The complex tasks of regulation and synthesis remain to be addressed by the use of liver cells (bioartificial liver support). The Extracorporeal Liver Assist Device (ELAD), HepatAssist, Modular Extracorporeal Liver Support system (MELS), and the Amsterdam Medical Center Bioartificial Liver (AMC-BAL) are bioartificial systems. This article gives a brief overview on these artificial and bioartificial devices and discusses remaining obstacles.

  9. Liver disease in pregnancy

    Institute of Scientific and Technical Information of China (English)

    Noel M Lee; Carla W Brady

    2009-01-01

    Liver diseases in pregnancy may be categorized into liver disorders that occur only in the setting of pregnancy and liver diseases that occur coincidentally with pregnancy. Hyperemesis gravidarum, preeclampsia/eclampsia, syndrome of hemolysis, elevated liver tests and low platelets (HELLP), acute fatty liver of pregnancy, and intrahepatic cholestasis of pregnancy are pregnancy-specific disorders that may cause elevations in liver tests and hepatic dysfunction. Chronic liver diseases, including cholestatic liver disease, autoimmune hepatitis, Wilson disease, and viral hepatitis may also be seen in pregnancy. Management of liver disease in pregnancy requires collaboration between obstetricians and gastroenterologists/hepatologists. Treatment of pregnancy-specific liver disorders usually involves delivery of the fetus and supportive care, whereas management of chronic liver disease in pregnancy is directed toward optimizing control of the liver disorder. Cirrhosis in the setting of pregnancy is less commonly observed but offers unique challenges for patients and practitioners. This article reviews the epidemiology, pathophysiology, diagnosis, and management of liver diseases seen in pregnancy.

  10. Autoimmune liver disease panel

    Science.gov (United States)

    Liver disease test panel - autoimmune ... Autoimmune disorders are a possible cause of liver disease. The most common of these diseases are autoimmune hepatitis and primary biliary cholangitis (formerly called primary biliary cirrhosis). This group of tests ...

  11. Alcoholic liver disease

    Science.gov (United States)

    Liver disease due to alcohol; Cirrhosis or hepatitis - alcoholic; Laennec's cirrhosis ... Alcoholic liver disease occurs after years of heavy drinking. Over time, scarring and cirrhosis can occur. Cirrhosis is the ...

  12. Antioxidants in liver health

    Institute of Scientific and Technical Information of China (English)

    Sael; Casas-Grajales; Pablo; Muriel

    2015-01-01

    Liver diseases are a worldwide medical problem because the liver is the principal detoxifying organ and maintains metabolic homeostasis. The liver metabolizes various compounds that produce free radicals(FR).However, antioxidants scavenge FR and maintain the oxidative/antioxidative balance in the liver. When the liver oxidative/antioxidative balance is disrupted, the state is termed oxidative stress. Oxidative stress leadsto deleterious processes in the liver and produces liver diseases. Therefore, restoring antioxidants is essential to maintain homeostasis. One method of restoring antioxidants is to consume natural compounds with antioxidant capacity. The objective of this review is to provide information pertaining to various antioxidants found in food that have demonstrated utility in improving liver diseases.

  13. Alcohol and liver, 2010

    Institute of Scientific and Technical Information of China (English)

    Natalia; A; Osna

    2010-01-01

    Liver is known as an organ that is primarily affected by alcohol. Alcoholic liver disease (ALD) is the cause of an increased morbidity and mortality worldwide. Progression of ALD is driven by "second hits". These second hits include the complex of nutritional, pharmacological, genetic and viral factors, which aggravate liver pathology. However, in addition to liver failure, ethanol causes damage to other organs and systems. These extrahepatic manifestations are regulated via the similar hepatitis mechanisms...

  14. Percutaneous liver biopsy.

    Science.gov (United States)

    Rustagi, Tarun; Newton, Eric; Kar, Premashish

    2010-01-01

    Percutaneous liver biopsy has been performed for more than 120 years, and remains an important diagnostic procedure for the management of hepatobiliary disorders. Modern biochemical, immunologic, and radiographic techniques have facilitated the diagnosis and management of liver diseases but have not made liver biopsy obsolete. This comprehensive review article will discuss the history of development of percutaneous liver biopsy, its indications, contraindications, complications and the various aspects of the biopsy procedure in detail.

  15. Non-viral FoxM1 gene delivery to hepatocytes enhances liver repopulation.

    Science.gov (United States)

    Xiang, D; Liu, C-C; Wang, M-J; Li, J-X; Chen, F; Yao, H; Yu, B; Lu, L; Borjigin, U; Chen, Y-X; Zhong, L; Wangensteen, K J; He, Z-Y; Wang, X; Hu, Y-P

    2014-05-22

    Hepatocyte transplantation as a substitute strategy of orthotopic liver transplantation is being studied for treating end-stage liver diseases. Several technical hurdles must be overcome in order to achieve the therapeutic liver repopulation, such as the problem of insufficient expansion of the transplanted hepatocytes in recipient livers. In this study, we analyzed the application of FoxM1, a cell-cycle regulator, to enhance the proliferation capacity of hepatocytes. The non-viral sleeping beauty (SB) transposon vector carrying FoxM1 gene was constructed for delivering FoxM1 into the hepatocytes. The proliferation capacities of hepatocytes with FoxM1 expression were examined both in vivo and in vitro. Results indicated that the hepatocytes with FoxM1 expression had a higher proliferation rate than wild-type (WT) hepatocytes in vitro. In comparison with WT hepatocytes, the hepatocytes with FoxM1 expression had an enhanced level of liver repopulation in the recipient livers at both sub-acute injury (fumaryl acetoacetate hydrolase (Fah)(-/-) mice model) and acute injury (2/3 partial hepatectomy mice model). Importantly, there was no increased risk of tumorigenicity with FoxM1 expression in recipients even after serial transplantation. In conclusion, expression of FoxM1 in hepatocytes enhanced the capacity of liver repopulation without inducing tumorigenesis. FoxM1 gene delivered by non-viral SB vector into hepatocytes may be a viable approach to promote therapeutic repopulation after hepatocyte transplantation.

  16. Slit2/Robo1 signaling promotes intestinal tumorigenesis through Src-mediated activation of the Wnt/β-catenin pathway.

    Science.gov (United States)

    Zhang, Qian-Qian; Zhou, Da-Lei; Lei, Yan; Zheng, Li; Chen, Sheng-Xia; Gou, Hong-Ju; Gu, Qu-Liang; He, Xiao-Dong; Lan, Tian; Qi, Cui-Ling; Li, Jiang-Chao; Ding, Yan-Qing; Qiao, Liang; Wang, Li-Jing

    2015-02-20

    Slit2 is often overexpressed in cancers. Slit2 is a secreted protein that binds to Roundabout (Robo) receptors to regulate cell growth and migration. Here, we employed several complementary mouse models of intestinal cancers, including the Slit2 transgenic mice, the ApcMin/+ spontaneous intestinal adenoma mouse model, and the DMH/DSS-induced colorectal carcinoma model to clarify function of Slit2/Robo1 signaling in intestinal tumorigenesis. We showed that Slit2 and Robo1 are overexpressed in intestinal tumors and may contribute to tumor generation. The Slit2/Robo1 signaling can induce precancerous lesions of the intestine and tumor progression. Ectopic expression of Slit2 activated Slit2/Robo1 signaling and promoted tumorigenesis and tumor growth. This was mediated in part through activation of the Src signaling, which then down-regulated E-cadherin, thereby activating Wnt/β-catenin signaling. Thus, Slit2/Robo1 signaling is oncogenic in intestinal tumorigenesis.

  17. Small heterodimer partner overexpression partially protects against liver tumor development in farnesoid X receptor knockout mice

    Energy Technology Data Exchange (ETDEWEB)

    Li, Guodong [Department of Surgical Oncology, Cancer Treatment Center, The Fourth Affiliated Hospital of Harbin Medical University, Harbin (China); Kong, Bo [Department of Pharmacology and Toxicology, School of Pharmacy, Rutgers University, Piscataway, NJ (United States); Zhu, Yan [Department of General Surgery, Xuanwu Hospital, Capital Medical University, Beijing (China); Zhan, Le [Department of Pharmacology and Toxicology, School of Pharmacy, Rutgers University, Piscataway, NJ (United States); Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States); Williams, Jessica A. [Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States); Tawfik, Ossama [Department of Pathology and Laboratory Medicine, University of Kansas Medical Center, Kansas City, KS (United States); Kassel, Karen M. [Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States); Luyendyk, James P. [Pathobiology and Diagnostic Investigation, Michigan State University, East Lansing, MI (United States); Wang, Li [Department of Medicine, Huntsman Cancer Institute, University of Utah School of Medicine, Salt Lake City, UT (United States); Guo, Grace L., E-mail: guo@eohsi.rutgers.edu [Department of Pharmacology and Toxicology, School of Pharmacy, Rutgers University, Piscataway, NJ (United States)

    2013-10-15

    Farnesoid X receptor (FXR, Nr1h4) and small heterodimer partner (SHP, Nr0b2) are nuclear receptors that are critical to liver homeostasis. Induction of SHP serves as a major mechanism of FXR in suppressing gene expression. Both FXR{sup −/−} and SHP{sup −/−} mice develop spontaneous hepatocellular carcinoma (HCC). SHP is one of the most strongly induced genes by FXR in the liver and is a tumor suppressor, therefore, we hypothesized that deficiency of SHP contributes to HCC development in the livers of FXR{sup −/−} mice and therefore, increased SHP expression in FXR{sup −/−} mice reduces liver tumorigenesis. To test this hypothesis, we generated FXR{sup −/−} mice with overexpression of SHP in hepatocytes (FXR{sup −/−}/SHP{sup Tg}) and determined the contribution of SHP in HCC development in FXR{sup −/−} mice. Hepatocyte-specific SHP overexpression did not affect liver tumor incidence or size in FXR{sup −/−} mice. However, SHP overexpression led to a lower grade of dysplasia, reduced indicator cell proliferation and increased apoptosis. All tumor-bearing mice had increased serum bile acid levels and IL-6 levels, which was associated with activation of hepatic STAT3. In conclusion, SHP partially protects FXR{sup −/−} mice from HCC formation by reducing tumor malignancy. However, disrupted bile acid homeostasis by FXR deficiency leads to inflammation and injury, which ultimately results in uncontrolled cell proliferation and tumorigenesis in the liver. - Highlights: • SHP does not prevent HCC incidence nor size in FXR KO mice but reduces malignancy. • Increased SHP promotes apoptosis. • Bile acids and inflammation maybe critical for HCC formation with FXR deficiency.

  18. Non-alcoholic steatohepatitis and preneoplastic lesions develop in the liver of obese and hypertensive rats: suppressing effects of EGCG on the development of liver lesions.

    Science.gov (United States)

    Kochi, Takahiro; Shimizu, Masahito; Terakura, Daishi; Baba, Atsushi; Ohno, Tomohiko; Kubota, Masaya; Shirakami, Yohei; Tsurumi, Hisashi; Tanaka, Takuji; Moriwaki, Hisataka

    2014-01-01

    Non-alcoholic steatohepatitis (NASH), which involves hepatic inflammation and fibrosis, is associated with liver carcinogenesis. The activation of the renin-angiotensin system (RAS), which plays a key role in blood pressure regulation, promotes hepatic fibrogenesis. In this study, we investigated the effects of (-)-epigallocatechin-3-gallate (EGCG), a major component of green tea catechins, on the development of glutathione S-transferase placental form (GST-P)-positive (GST-P(+)) foci, a hepatic preneoplastic lesion, in SHRSP.Z-Lepr(fa)/IzmDmcr (SHRSP-ZF) obese and hypertensive rats. Male 7-week-old SHRSP-ZF rats and control non-obese and normotensive WKY rats were fed a high fat diet and received intraperitoneal injections of carbon tetrachloride twice a week for 8weeks. The rats were also provided tap water containing 0.1% EGCG during the experiment. SHRSP-ZF rats presented with obesity, insulin resistance, dyslipidemia, an imbalance of adipokines in the serum, and hepatic steatosis. The development of GST-P(+) foci and liver fibrosis was markedly accelerated in SHRSP-ZF rats compared to that in control rats. Additionally, in SHRSP-ZF rats, RAS was activated and inflammation and oxidative stress were induced. Administration of EGCG, however, inhibited the development of hepatic premalignant lesions by improving liver fibrosis, inhibiting RAS activation, and attenuating inflammation and oxidative stress in SHRSP-ZF rats. In conclusion, obese and hypertensive SHRSP-ZF rats treated with a high fat diet and carbon tetrachloride displayed the histopathological and pathophysiological characteristics of NASH and developed GST-P(+) foci hepatic premalignant lesions, suggesting the model might be useful for the evaluation of NASH-related liver tumorigenesis. EGCG might also be able to prevent NASH-related liver fibrosis and tumorigenesis. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  19. Loss of p53 Ser18 and Atm results in embryonic lethality without cooperation in tumorigenesis.

    Directory of Open Access Journals (Sweden)

    Heather L Armata

    Full Text Available Phosphorylation at murine Serine 18 (human Serine 15 is a critical regulatory process for the tumor suppressor function of p53. p53Ser18 residue is a substrate for ataxia-telangiectasia mutated (ATM and ATM-related (ATR protein kinases. Studies of mice with a germ-line mutation that replaces Ser18 with Ala (p53(S18A mice have demonstrated that loss of phosphorylation of p53Ser18 leads to the development of tumors, including lymphomas, fibrosarcomas, leukemia and leiomyosarcomas. The predominant lymphoma is B-cell lymphoma, which is in contrast to the lymphomas observed in Atm(-/- animals. This observation and the fact that multiple kinases phosphorylate p53Ser18 suggest Atm-independent tumor suppressive functions of p53Ser18. Therefore, in order to examine p53Ser18 function in relationship to ATM, we analyzed the lifespan and tumorigenesis of mice with combined mutations in p53Ser18 and Atm. Surprisingly, we observed no cooperation in survival and tumorigenesis in compound p53(S18A and Atm(-/- animals. However, we observed embryonic lethality in the compound mutant animals. In addition, the homozygous p53Ser18 mutant allele impacted the weight of Atm(-/- animals. These studies examine the genetic interaction of p53Ser18 and Atm in vivo. Furthermore, these studies demonstrate a role of p53Ser18 in regulating embryonic survival and motor coordination.

  20. Elevated NIBP/TRAPPC9 mediates tumorigenesis of cancer cells through NFκB signaling.

    Science.gov (United States)

    Zhang, Yonggang; Liu, Shu; Wang, Hong; Yang, Wensheng; Li, Fang; Yang, Fan; Yu, Daohai; Ramsey, Frederick V; Tuszyski, George P; Hu, Wenhui

    2015-03-20

    Regulatory mechanisms underlying constitutive and inducible NFκB activation in cancer remain largely unknown. Here we investigated whether a novel NIK- and IKK2-binding protein (NIBP) is required for maintaining malignancy of cancer cells in an NFκB-dependent manner. Real-time polymerase chain reaction analysis of a human cancer survey tissue-scan cDNA array, immunostaining of a human frozen tumor tissue array and immunoblotting of a high-density reverse-phase cancer protein lysate array showed that NIBP is extensively expressed in most tumor tissues, particularly in breast and colon cancer. Lentivirus-mediated NIBP shRNA knockdown significantly inhibited the growth/proliferation, invasion/migration, colony formation and xenograft tumorigenesis of breast (MDA-MB-231) or colon (HCT116) cancer cells. NIBP overexpression in HCT116 cells promoted cell proliferation, migration and colony formation. Mechanistically, NIBP knockdown in cancer cells inhibited cytokine-induced activation of NFκB luciferase reporter, thus sensitizing the cells to TNFα-induced apoptosis. Endogenous NIBP bound specifically to the phosphorylated IKK2 in a TNFα-dependent manner. NIBP knockdown transiently attenuated TNFα-stimulated phosphorylation of IKK2/p65 and degradation of IκBα. In contrast, NIBP overexpression enhanced TNFα-induced NFκB activation, thus inhibiting constitutive and TNFα-induced apoptosis. Collectively, our data identified important roles of NIBP in promoting tumorigenesis via NFκΒ signaling, spotlighting NIBP as a promising target in cancer therapeutic intervention.

  1. miR-92a family and their target genes in tumorigenesis and metastasis

    Energy Technology Data Exchange (ETDEWEB)

    Li, Molin, E-mail: molin_li@hotmail.com [Department of Pathophysiology, Basic Medical Science of Dalian Medical University, Dalian 116044 (China); Institute of Cancer Stem Cell, Dalian Medical University Cancer Center, Dalian 116044 (China); Guan, Xingfang; Sun, Yuqiang [Department of Pathophysiology, Basic Medical Science of Dalian Medical University, Dalian 116044 (China); Mi, Jun [Institute of Cancer Stem Cell, Dalian Medical University Cancer Center, Dalian 116044 (China); Shu, Xiaohong [College of Pharmacy, Dalian Medical University Cancer Center, Dalian 116044 (China); Liu, Fang [Department of Surgery, The Second Affiliated Hospital of Dalian Medical University, Dalian 116027 (China); Li, Chuangang, E-mail: li_chuangang@sina.com [Department of Surgery, The Second Affiliated Hospital of Dalian Medical University, Dalian 116027 (China)

    2014-04-15

    The miR-92a family, including miR-25, miR-92a-1, miR-92a-2 and miR-363, arises from three different paralog clusters miR-17-92, miR-106a-363, and miR-106b-25 that are highly conservative in the process of evolution, and it was thought as a group of microRNAs (miRNAs) correlated with endothelial cells. Aberrant expression of miR-92a family was detected in multiple cancers, and the disturbance of miR-92a family was related with tumorigenesis and tumor development. In this review, the progress on the relationship between miR-92a family and their target genes and malignant tumors will be summarized. - Highlights: • Aberrant expression of miR-92a, miR-25 and miR-363 can be observed in many kinds of malignant tumors. • The expression of miR-92a family is regulated by LOH, epigenetic alteration, transcriptional factors such as SP1, MYC, E2F, wild-type p53 etc. • Roles of miR-92a family in tumorigenesis and development: promoting cell proliferation, invasion and metastasis, inhibiting cell apoptosis.

  2. Polyamine catabolism contributes to enterotoxigenic Bacteroides fragilis-induced colon tumorigenesis.

    Science.gov (United States)

    Goodwin, Andrew C; Destefano Shields, Christina E; Wu, Shaoguang; Huso, David L; Wu, XinQun; Murray-Stewart, Tracy R; Hacker-Prietz, Amy; Rabizadeh, Shervin; Woster, Patrick M; Sears, Cynthia L; Casero, Robert A

    2011-09-13

    It is estimated that the etiology of 20-30% of epithelial cancers is directly associated with inflammation, although the direct molecular events linking inflammation and carcinogenesis are poorly defined. In the context of gastrointestinal disease, the bacterium enterotoxigenic Bacteroides fragilis (ETBF) is a significant source of chronic inflammation and has been implicated as a risk factor for colorectal cancer. Spermine oxidase (SMO) is a polyamine catabolic enzyme that is highly inducible by inflammatory stimuli resulting in increased reactive oxygen species (ROS) and DNA damage. We now demonstrate that purified B. fragilis toxin (BFT) up-regulates SMO in HT29/c1 and T84 colonic epithelial cells, resulting in SMO-dependent generation of ROS and induction of γ-H2A.x, a marker of DNA damage. Further, ETBF-induced colitis in C57BL/6 mice is associated with increased SMO expression and treatment of mice with an inhibitor of polyamine catabolism, N(1),N(4)-bis(2,3-butandienyl)-1,4-butanediamine (MDL 72527), significantly reduces ETBF-induced chronic inflammation and proliferation. Most importantly, in the multiple intestinal neoplasia (Min) mouse model, treatment with MDL 72527 reduces ETBF-induced colon tumorigenesis by 69% (P < 0.001). The results of these studies indicate that SMO is a source of bacteria-induced ROS directly associated with tumorigenesis and could serve as a unique target for chemoprevention.

  3. Polyamine catabolism contributes to enterotoxigenic Bacteroides fragilis-induced colon tumorigenesis

    Science.gov (United States)

    Goodwin, Andrew C.; Shields, Christina E. Destefano; Wu, Shaoguang; Huso, David L.; Wu, XinQun; Murray-Stewart, Tracy R.; Hacker-Prietz, Amy; Rabizadeh, Shervin; Woster, Patrick M.; Sears, Cynthia L.; Casero, Robert A.

    2011-01-01

    It is estimated that the etiology of 20–30% of epithelial cancers is directly associated with inflammation, although the direct molecular events linking inflammation and carcinogenesis are poorly defined. In the context of gastrointestinal disease, the bacterium enterotoxigenic Bacteroides fragilis (ETBF) is a significant source of chronic inflammation and has been implicated as a risk factor for colorectal cancer. Spermine oxidase (SMO) is a polyamine catabolic enzyme that is highly inducible by inflammatory stimuli resulting in increased reactive oxygen species (ROS) and DNA damage. We now demonstrate that purified B. fragilis toxin (BFT) up-regulates SMO in HT29/c1 and T84 colonic epithelial cells, resulting in SMO-dependent generation of ROS and induction of γ-H2A.x, a marker of DNA damage. Further, ETBF-induced colitis in C57BL/6 mice is associated with increased SMO expression and treatment of mice with an inhibitor of polyamine catabolism, N1,N4-bis(2,3-butandienyl)-1,4-butanediamine (MDL 72527), significantly reduces ETBF-induced chronic inflammation and proliferation. Most importantly, in the multiple intestinal neoplasia (Min) mouse model, treatment with MDL 72527 reduces ETBF-induced colon tumorigenesis by 69% (P < 0.001). The results of these studies indicate that SMO is a source of bacteria-induced ROS directly associated with tumorigenesis and could serve as a unique target for chemoprevention. PMID:21876161

  4. Nisin, an apoptogenic bacteriocin and food preservative, attenuates HNSCC tumorigenesis via CHAC1.

    Science.gov (United States)

    Joo, Nam E; Ritchie, Kathryn; Kamarajan, Pachiyappan; Miao, Di; Kapila, Yvonne L

    2012-12-01

    Nisin, a bacteriocin and commonly used food preservative, may serve as a novel potential therapeutic for treating head and neck squamous cell carcinoma (HNSCC), as it induces preferential apoptosis, cell cycle arrest, and reduces cell proliferation in HNSCC cells, compared with primary keratinocytes. Nisin also reduces HNSCC tumorigenesis in vivo. Mechanistically, nisin exerts these effects on HNSCC, in part, through CHAC1, a proapoptotic cation transport regulator, and through a concomitant CHAC1-independent influx of extracellular calcium. In addition, although CHAC1 is known as an apoptotic mediator, its effects on cancer cell apoptosis have not been examined. Our studies are the first to report CHAC1's new role in promoting cancer cell apoptosis under nisin treatment. These data support the concept that nisin decreases HNSCC tumorigenesis in vitro and in vivo by inducing increased cell apoptosis and decreased cell proliferation; effects that are mediated by activation of CHAC1, increased calcium influxes, and induction of cell cycle arrest. These findings support the use of nisin as a potentially novel therapeutic for HNSCC, and as nisin is safe for human consumption and currently used in food preservation, its translation into a clinical setting may be facilitated.

  5. Suppression of CHK1 by ETS Family Members Promotes DNA Damage Response Bypass and Tumorigenesis.

    Science.gov (United States)

    Lunardi, Andrea; Varmeh, Shohreh; Chen, Ming; Taulli, Riccardo; Guarnerio, Jlenia; Ala, Ugo; Seitzer, Nina; Ishikawa, Tomoki; Carver, Brett S; Hobbs, Robin M; Quarantotti, Valentina; Ng, Christopher; Berger, Alice H; Nardella, Caterina; Poliseno, Laura; Montironi, Rodolfo; Castillo-Martin, Mireia; Cordon-Cardo, Carlos; Signoretti, Sabina; Pandolfi, Pier Paolo

    2015-05-01

    The ETS family of transcription factors has been repeatedly implicated in tumorigenesis. In prostate cancer, ETS family members, such as ERG, ETV1, ETV4, and ETV5, are frequently overexpressed due to chromosomal translocations, but the molecular mechanisms by which they promote prostate tumorigenesis remain largely undefined. Here, we show that ETS family members, such as ERG and ETV1, directly repress the expression of the checkpoint kinase 1 (CHK1), a key DNA damage response cell-cycle regulator essential for the maintenance of genome integrity. Critically, we find that ERG expression correlates with CHK1 downregulation in human patients and demonstrate that Chk1 heterozygosity promotes the progression of high-grade prostatic intraepithelial neoplasia into prostatic invasive carcinoma in Pten(+) (/-) mice. Importantly, CHK1 downregulation sensitizes prostate tumor cells to etoposide but not to docetaxel treatment. Thus, we identify CHK1 as a key functional target of the ETS proto-oncogenic family with important therapeutic implications. Genetic translocation and aberrant expression of ETS family members is a common event in different types of human tumors. Here, we show that through the transcriptional repression of CHK1, ETS factors may favor DNA damage accumulation and consequent genetic instability in proliferating cells. Importantly, our findings provide a rationale for testing DNA replication inhibitor agents in ETS-positive TP53-proficient tumors. ©2015 American Association for Cancer Research.

  6. Genetic mapping of Mom5, a novel modifier of Apc(Min)-induced intestinal tumorigenesis.

    Science.gov (United States)

    Oikarinen, Seija I; Cleveland, Alicia G; Cork, Karlene M; Bynoté, Kimberly K; Rafter, Joseph J; Gustafsson, Jan-Ake; Mutanen, Marja; Gould, Karen A

    2009-09-01

    The initial purpose of this study was to assess the role of estrogen receptor beta (ERbeta) in intestinal tumorigenesis by examining the effects of an ERbeta knockout (ERbeta(-/-)) on Apc(Min) mice. In order to accomplish this goal on a uniform genetic background, we were required to backcross the ERbeta knockout from the 129P2 genetic background to the B6 genetic background for 10 generations. Midway through this process, we performed a test cross in which mice from the N(5) backcross generation of the ERbeta knockout strain were intercrossed with Apc(Min/+) mice to obtain Apc(Min/+) ERbeta(+/+), Apc(Min/+) ERbeta(+/-) and Apc(Min/+) ERbeta(-/-) mice. Intestinal tumorigenesis in the N(5)F(2) mice was evaluated at 14 weeks of age. The analysis of the impact of ERbeta in the N(5) cross was complicated by segregating 129P2-derived alleles that affected tumor number and were unlinked to ERbeta. Genetic linkage analysis of this cross permitted the localization of a single genetic modifier of tumor number in Apc(Min/+) mice. This locus, Modifier of Min 5 (Mom5), maps to proximal mouse chromosome 5; the 129P2 allele of this locus is associated with a 50% reduction in mean intestinal tumor number. Through in silico analysis and confirmatory sequencing, we have identified the Rad50-interacting protein-1 gene as a strong candidate for Mom5.

  7. miR-100 induces epithelial-mesenchymal transition but suppresses tumorigenesis, migration and invasion.

    Directory of Open Access Journals (Sweden)

    Dahu Chen

    2014-02-01

    Full Text Available Whether epithelial-mesenchymal transition (EMT is always linked to increased tumorigenicity is controversial. Through microRNA (miRNA expression profiling of mammary epithelial cells overexpressing Twist, Snail or ZEB1, we identified miR-100 as a novel EMT inducer. Surprisingly, miR-100 inhibits the tumorigenicity, motility and invasiveness of mammary tumor cells, and is commonly downregulated in human breast cancer due to hypermethylation of its host gene MIR100HG. The EMT-inducing and tumor-suppressing effects of miR-100 are mediated by distinct targets. While miR-100 downregulates E-cadherin by targeting SMARCA5, a regulator of CDH1 promoter methylation, this miRNA suppresses tumorigenesis, cell movement and invasion in vitro and in vivo through direct targeting of HOXA1, a gene that is both oncogenic and pro-invasive, leading to repression of multiple HOXA1 downstream targets involved in oncogenesis and invasiveness. These findings provide a proof-of-principle that EMT and tumorigenicity are not always associated and that certain EMT inducers can inhibit tumorigenesis, migration and invasion.

  8. Impaired PRC2 activity promotes transcriptional instability and favors breast tumorigenesis

    Science.gov (United States)

    Wassef, Michel; Rodilla, Veronica; Teissandier, Aurélie; Zeitouni, Bruno; Gruel, Nadege; Sadacca, Benjamin; Irondelle, Marie; Charruel, Margaux; Ducos, Bertrand; Michaud, Audrey; Caron, Matthieu; Marangoni, Elisabetta; Chavrier, Philippe; Le Tourneau, Christophe; Kamal, Maud; Pasmant, Eric; Vidaud, Michel; Servant, Nicolas; Reyal, Fabien; Meseure, Dider; Vincent-Salomon, Anne; Fre, Silvia; Margueron, Raphaël

    2015-01-01

    Alterations of chromatin modifiers are frequent in cancer, but their functional consequences often remain unclear. Focusing on the Polycomb protein EZH2 that deposits the H3K27me3 (trimethylation of Lys27 of histone H3) mark, we showed that its high expression in solid tumors is a consequence, not a cause, of tumorigenesis. In mouse and human models, EZH2 is dispensable for prostate cancer development and restrains breast tumorigenesis. High EZH2 expression in tumors results from a tight coupling to proliferation to ensure H3K27me3 homeostasis. However, this process malfunctions in breast cancer. Low EZH2 expression relative to proliferation and mutations in Polycomb genes actually indicate poor prognosis and occur in metastases. We show that while altered EZH2 activity consistently modulates a subset of its target genes, it promotes a wider transcriptional instability. Importantly, transcriptional changes that are consequences of EZH2 loss are predominantly irreversible. Our study provides an unexpected understanding of EZH2's contribution to solid tumors with important therapeutic implications. PMID:26637281

  9. Diet induced obesity increases the risk of colonic tumorigenesis in mice.

    Science.gov (United States)

    Sikalidis, Angelos K; Fitch, Mark D; Fleming, Sharon E

    2013-10-01

    A large body of epidemiological data indicates that obesity increases the risk of colon cancer in humans. There are limited studies using rodent models where the relationship between obesity and colon cancer has been studied. In this study, wild-type diet-induced obese (DIO) mice and lean wild-type controls were used to investigate the influence of obesity on the risk of colon cancer. We hypothesized that the obese phenotype would exhibit increased colonic tumorigenesis. Colon cancer was chemically induced by injecting the mice with azoxymethane (AOM) at levels that we experimentally determined to result in equivalent AOM concentrations in circulating blood. Risk of colon cancer was assessed via microscopic examination of entire colons for aberrant crypts, aberrant crypt foci and proliferation levels. The DIO mice were found to have significantly more aberrant crypts and aberrant crypt foci as well as increased proliferation of colonocytes per mouse compared to wild-type control mice, supporting the epidemiological data that obesity increases the risk of colonic tumorigenesis.

  10. Twist1 suppresses senescence programs and thereby accelerates and maintains mutant Kras-induced lung tumorigenesis.

    Directory of Open Access Journals (Sweden)

    Phuoc T Tran

    Full Text Available KRAS mutant lung cancers are generally refractory to chemotherapy as well targeted agents. To date, the identification of drugs to therapeutically inhibit K-RAS have been unsuccessful, suggesting that other approaches are required. We demonstrate in both a novel transgenic mutant Kras lung cancer mouse model and in human lung tumors that the inhibition of Twist1 restores a senescence program inducing the loss of a neoplastic phenotype. The Twist1 gene encodes for a transcription factor that is essential during embryogenesis. Twist1 has been suggested to play an important role during tumor progression. However, there is no in vivo evidence that Twist1 plays a role in autochthonous tumorigenesis. Through two novel transgenic mouse models, we show that Twist1 cooperates with Kras(G12D to markedly accelerate lung tumorigenesis by abrogating cellular senescence programs and promoting the progression from benign adenomas to adenocarcinomas. Moreover, the suppression of Twist1 to physiological levels is sufficient to cause Kras mutant lung tumors to undergo senescence and lose their neoplastic features. Finally, we analyzed more than 500 human tumors to demonstrate that TWIST1 is frequently overexpressed in primary human lung tumors. The suppression of TWIST1 in human lung cancer cells also induced cellular senescence. Hence, TWIST1 is a critical regulator of cellular senescence programs, and the suppression of TWIST1 in human tumors may be an effective example of pro-senescence therapy.

  11. Mechanisms by Which Interleukin-6 Attenuates Cell Invasion and Tumorigenesis in Human Bladder Carcinoma Cells

    Directory of Open Access Journals (Sweden)

    Ke-Hung Tsui

    2013-01-01

    Full Text Available Interleukin-6, a multifunctional cytokine, contributes to tumor cell proliferation and differentiation. However, the biological mechanisms that are affected by the expression of interleukin-6 in bladder cancer cells remain unclear. We evaluated the effects of interleukin-6 expression in human bladder carcinoma cells in vitro and in vivo. The results of interleukin-6-knockdown experiments in T24 cells and interleukin-6-overexpression experiments in HT1376 cells revealed that interleukin-6 reduced cell proliferation, migration, and invasion in vitro. Xenograft animal studies indicated that the overexpression of interleukin-6 downregulated tumorigenesis of bladder cells and that interleukin-6 knockdown reversed this effect. The results of RT-PCR, immunoblotting, and reporter assays indicated that the overexpression of interleukin-6 upregulated the expression of the mammary serine protease inhibitor (MASPIN, N-myc downstream gene 1 (NDRG1, and KAI1 proteins in HT1376 cells and that interleukin-6 knockdown reduced the expression of these proteins in T24 cells. In addition, results of immunoblotting assays revealed that interleukin-6 modulated epithelial-mesenchymal transitions by upregulating the expression of the E-cadherin, while downregulation N-cadherin and vimentin proteins. Our results suggest that the effects of interleukin-6 on the regulation of epithelial-mesenchymal transitions and the expressions of the MASPIN, NDRG1, and KAI1 genes attribute to the modulation of tumorigenesis in human bladder carcinoma cells.

  12. Impaired PRC2 activity promotes transcriptional instability and favors breast tumorigenesis.

    Science.gov (United States)

    Wassef, Michel; Rodilla, Veronica; Teissandier, Aurélie; Zeitouni, Bruno; Gruel, Nadege; Sadacca, Benjamin; Irondelle, Marie; Charruel, Margaux; Ducos, Bertrand; Michaud, Audrey; Caron, Matthieu; Marangoni, Elisabetta; Chavrier, Philippe; Le Tourneau, Christophe; Kamal, Maud; Pasmant, Eric; Vidaud, Michel; Servant, Nicolas; Reyal, Fabien; Meseure, Dider; Vincent-Salomon, Anne; Fre, Silvia; Margueron, Raphaël

    2015-12-15

    Alterations of chromatin modifiers are frequent in cancer, but their functional consequences often remain unclear. Focusing on the Polycomb protein EZH2 that deposits the H3K27me3 (trimethylation of Lys27 of histone H3) mark, we showed that its high expression in solid tumors is a consequence, not a cause, of tumorigenesis. In mouse and human models, EZH2 is dispensable for prostate cancer development and restrains breast tumorigenesis. High EZH2 expression in tumors results from a tight coupling to proliferation to ensure H3K27me3 homeostasis. However, this process malfunctions in breast cancer. Low EZH2 expression relative to proliferation and mutations in Polycomb genes actually indicate poor prognosis and occur in metastases. We show that while altered EZH2 activity consistently modulates a subset of its target genes, it promotes a wider transcriptional instability. Importantly, transcriptional changes that are consequences of EZH2 loss are predominantly irreversible. Our study provides an unexpected understanding of EZH2's contribution to solid tumors with important therapeutic implications.

  13. Diverse roles of C-terminal Hsp70-interacting protein (CHIP) in tumorigenesis.

    Science.gov (United States)

    Sun, Chao; Li, Hai-Long; Shi, Mei-Lin; Liu, Qing-Hua; Bai, Jin; Zheng, Jun-Nian

    2014-02-01

    The carboxyl terminus of Hsp70-interacting protein (CHIP) is a member of E3 ubiquitin ligase, functioning as a link between the chaperone (heat shock protein 70/90) and proteasome systems, playing a vital role in maintaining the protein homeostasis in the cytoplasm. CHIP has been demonstrated to be involved in tumorigenesis, proliferation and invasion in several malignancies, regulating a number of oncogenic proteins. However, CHIP has also been implicated in the modulation of tumor suppressor proteins. The pathogenic mechanism of CHIP expression in human malignancy is not yet clear, and a number of studies have suggested that CHIP may have opposing roles in different cancers. Therefore, many studies have focused on the relationship between CHIP and carcinoma. A literature search focusing on regulation network, biological function and clinical significance of CHIP in connection with its role in cancer development was performed on the MEDLINE databases. CHIP may be a potential diagnostic biomarker and therapeutic target for human cancer, and may play different roles in different human cancers. This inconsistence might be induced by the diversity of CHIP downstream targeting proteins. Therefore, the phenotypes determined by CHIP should be dependent on the function of its specific targets in a specific type of cancer cells. Whether CHIP contributes to tumor progression or suppression in various human cancers remains unclear, suggesting the necessity of further extensive investigation of its role in tumorigenesis.

  14. The Rab2A GTPase Promotes Breast Cancer Stem Cells and Tumorigenesis via Erk Signaling Activation

    Directory of Open Access Journals (Sweden)

    Man-Li Luo

    2015-04-01

    Full Text Available Proline-directed phosphorylation is regulated by the prolyl isomerase Pin1, which plays a fundamental role in driving breast cancer stem-like cells (BCSCs. Rab2A is a small GTPase critical for vesicle trafficking. Here, we show that Pin1 increases Rab2A transcription to promote BCSC expansion and tumorigenesis in vitro and in vivo. Mechanistically, Rab2A directly interacts with and prevents dephosphorylation/inactivation of Erk1/2 by the MKP3 phosphatase, resulting in Zeb1 upregulation and β-catenin nuclear translocation. In cancer cells, Rab2A is activated via gene amplification, mutation or Pin1 overexpression. Rab2A overexpression or mutation endows BCSC traits to primary normal human breast epithelial cells, whereas silencing Rab2A potently inhibits the expansion and tumorigenesis of freshly isolated BCSCs. Finally, Rab2A overexpression correlates with poor clinical outcome in breast cancer patients. Thus, Pin1/Rab2A/Erk drives BCSC expansion and tumorigenicity, suggesting potential drug targets.

  15. "The Lower Threshold" phenomenon in tumor cells toward endogenous digitalis-like compounds: Responsible for tumorigenesis?

    Directory of Open Access Journals (Sweden)

    Heidrun Weidemann

    2012-01-01

    Full Text Available Since their first discovery as potential anti-cancer drugs decades ago, there is increasing evidence that digitalis-like compounds (DLC have anti-tumor effects. Less is known about endogenous DLC (EDLC metabolism and regulation. As stress hormones synthesized in and secreted from the adrenal gland, they likely take part in the hypothalamo-pituitary-adrenal (HPA axis. In a previous study, we revealed reduced EDLC concentrations in plasma and organs from immune-compromised animals and proposed that a similar situation of a deregulated HPA axis with "adrenal EDLF exhaustion" may contribute to tumorigenesis in chronic stress situations. Here, we put forward the hypothesis that a lowered EDLC response threshold of tumor cells as compared with normal cells increases the risk of tumorigenesis, especially in those individuals with reduced EDLC plasma concentrations after chronic stress exposure. We will evaluate this hypothesis by (a summarizing the effects of different DLC concentrations on tumor as compared with normal cells and (b reviewing some essential differences in the Na/K-ATPase of tumor as compared with normal cells (isoform pattern, pump activity, mutations of other signalosome receptors. We will conclude that (1 tumor cells, indeed, seem to have their individual "physiologic" EDLC response range that already starts at pmolar levels and (2 that individuals with markedly reduced (pmolar EDLC plasma levels are predisposed to cancer because these EDLC concentrations will predominantly stimulate the proliferation of tumor cells. Finally, we will summarize preliminary results from our department supporting this hypothesis.

  16. Angiogenesis is a link between atherosclerosis and tumorigenesis: role of LOX-1.

    Science.gov (United States)

    Jiang, Junlin; Yan, Meiling; Mehta, Jawahar L; Hu, Changping

    2011-10-01

    Angiogenesis is defined as the formation of new blood vessels sprouting from pre-existing vessels. It plays an important role not only in physiological situations such as embryonic vascular development and wound healing, but also in pathological conditions including atherogenesis and evolution and spread of certain tumors. Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), a receptor for oxidized low density lipoprotein (ox-LDL), is mainly expressed in endothelial cells. It has diverse physiological functions and it could be a link between atherogenesis and tumorigenesis. The risk factors for atherosclerosis like hypertension, diabetes mellitus and hyperlipidemia are associated with LOX-1. Dyslipidemia and obesity are also being recognized as risk factor for certain tumors. LOX-1 is also found to be important for maintaining the transformed state in developmentally diverse cancer cell lines and for tumor growth. There is emerging evidence that LOX-1 plays an important role in the angiogenesis process. In this review, we outline the roles of angiogenesis in atherogenesis and tumorigenesis, and describe the role of LOX-1 as a potential molecular target for blocking angiogenesis.

  17. DNA Methylation Dynamics During Differentiation, Proliferation, and Tumorigenesis in the Intestinal Tract

    Science.gov (United States)

    Huang, Can-Ze

    2015-01-01

    DNA methylation, an epigenetic control mechanism in mammals, is widely present in the intestinal tract during the differentiation and proliferation of epithelial cells. Cells in stem cell pools or villi have different patterns of DNA methylation. The process of DNA methylation is dynamic and occurs at many relevant regulatory elements during the rapid transition of stem cells into fully mature, differentiated epithelial cells. Changes in DNA methylation patterns most often take place in enhancer and promoter regions and are associated with transcription factor binding. During differentiation, enhancer regions associated with genes important to enterocyte differentiation are demethylated, activating gene expression. Abnormal patterns of DNA methylation during differentiation and proliferation in the intestinal tract can lead to the formation of aberrant crypt foci and destroy the barrier and absorptive functions of the intestinal epithelium. Accumulation of these epigenetic changes may even result in tumorigenesis. In the current review, we discuss recent findings on the association between DNA methylation and cell differentiation and proliferation in the small intestine and highlight the possible links between dysregulation of this process and tumorigenesis. PMID:26413818

  18. Functional characterization of AMP-activated protein kinase signaling in tumorigenesis.

    Science.gov (United States)

    Cheng, Ji; Zhang, Tao; Ji, Hongbin; Tao, Kaixiong; Guo, Jianping; Wei, Wenyi

    2016-12-01

    AMP-activated protein kinase (AMPK) is a ubiquitously expressed metabolic sensor among various species. Specifically, cellular AMPK is phosphorylated and activated under certain stressful conditions, such as energy deprivation, in turn to activate diversified downstream substrates to modulate the adaptive changes and maintain metabolic homeostasis. Recently, emerging evidences have implicated the potential roles of AMPK signaling in tumor initiation and progression. Nevertheless, a comprehensive description on such topic is still in scarcity, especially in combination of its biochemical features with mouse modeling results to elucidate the physiological role of AMPK signaling in tumorigenesis. Hence, we performed this thorough review by summarizing the tumorigenic role of each component along the AMPK signaling, comprising of both its upstream and downstream effectors. Moreover, their functional interplay with the AMPK heterotrimer and exclusive efficacies in carcinogenesis were chiefly explained among genetically altered mice models. Importantly, the pharmaceutical investigations of AMPK relevant medications have also been highlighted. In summary, in this review, we not only elucidate the potential functions of AMPK signaling pathway in governing tumorigenesis, but also potentiate the future targeted strategy aiming for better treatment of aberrant metabolism-associated diseases, including cancer.

  19. A diterpenoid derivative 15-oxospiramilactone inhibits Wnt/β-catenin signaling and colon cancer cell tumorigenesis

    Institute of Scientific and Technical Information of China (English)

    Wei Wang; Haiyang Liu; Sheng Wang; Xiaojiang Hao; Lin Li

    2011-01-01

    The Wnt/β-catenin signaling pathway is a highly conserved pathway in organism evolution and regulates many biological processes. Aberrant activation of the Wnt/β-catenin signaling pathway is closely related to tumorigenesis.In order to identify potent small molecules to treat the over-activated Wnt signaling-mediated cancer, such as colon cancer, we established a mammalian cell line-based reporter gene screening system. The screen revealed a diterpenoid derivative, 15-oxospiramilactone(NC043)that inhibits Wnt3a or LiCl-stimulated Top-flash reporter activity in HEK293T cells and growth of colon cancer cells, SW480 and Caco-2. Treatment of SW480 cells with NC043 led to decreases in the mRNA and/or protein expression of Wnt target genes Axin2, Cyclin Dl and Survivin, as well as decreases in the protein levels of Cdc25c and Cdc2.NC043 did not affect the cytosol-nuclear distribution and protein level of soluble β-catenin, but decreased β-catenin/TCF4 association in SW480 cells. Moreover, NC043 inhibited anchorage-independent growth and xenograft tumorigenesis of SW480 cells. Collectively these results demonstrate that NC043 is a novel small molecule that inhibits canonical Wnt signaling downstream of P-catenin stability and may be a potential compound for treating colorectal cancer.

  20. Oncogenic role of clusterin overexpression in multistage colorectal tumorigenesis and progression

    Institute of Scientific and Technical Information of China (English)

    Dan Xie; Liang Hu; Xin-Yuan Guan; Jonathan S.T. Sham; Wei-Fen Zeng; Li-Hong Che; Meng Zhang; Hui-Xi Wu; Han-Liang Lin; Jian-Ming Wen; Sze Hang Lau

    2005-01-01

    AIM: To investigate the expression pattern of clusterin in colorectal adenoma-carcinoma-metastasis series, and to explore the potential role of dusterin in multistage colorectal tumorigenesis and progression.METHOD:S: A colorectal carcinoma (CRC)-tissue microarray (TMA), which contained 85 advanced CRCs including 43 cases of Dukes B, 21 of Dukes C and 21 of Dukes D tumors, were used for assessing the expression of clusterin (clone 41D) and tumor cell apoptotic index (AI) by immunohistochemistry and TUNEL assay, respectively. Moreover the potential correlation of dusterin expression with the patient'sclinical-pathological features were also examined. RESULTS: The positive staining of clusterin in different colorectal tissues was primarily a cytoplasmic pattern. Cytoplasmic overexpression of clusterin was detected in none of the normal coloredal mucosa, 17% of the adenomas, 46% of the primary CRCs, and 57% of the CRC metastatic lesions. In addition, a significant positive correlation between overexpression of clusterin and advanced clinical (Dukes) stage was observed (P<0.01). Overexpression of cytoplasmic clusterin in CRCs was inversely correlated with tumor apoptotic index (P<0.01), indicating the anti apoptotic function of cytoplasmic clusterin in CRCs.CONCLUSION: These data suggests that overexpression of cytoplasmic dustin might be involved in the tumorigenesis and/or progression of CRCs. The anti-apoptotic function of cytoplasmic dusterin may be responsible, at least in part, for the development and biologically aggressive behavior of CRC.

  1. Synergistic interaction of Rnf8 and p53 in the protection against genomic instability and tumorigenesis.

    Directory of Open Access Journals (Sweden)

    Marie-Jo Halaby

    Full Text Available Rnf8 is an E3 ubiquitin ligase that plays a key role in the DNA damage response as well as in the maintenance of telomeres and chromatin remodeling. Rnf8(-/- mice exhibit developmental defects and increased susceptibility to tumorigenesis. We observed that levels of p53, a central regulator of the cellular response to DNA damage, increased in Rnf8(-/- mice in a tissue- and cell type-specific manner. To investigate the role of the p53-pathway inactivation on the phenotype observed in Rnf8(-/- mice, we have generated Rnf8(-/-p53(-/- mice. Double-knockout mice showed similar growth retardation defects and impaired class switch recombination compared to Rnf8(-/- mice. In contrast, loss of p53 fully rescued the increased apoptosis and reduced number of thymocytes and splenocytes in Rnf8(-/- mice. Similarly, the senescence phenotype of Rnf8(-/- mouse embryonic fibroblasts was rescued in p53 null background. Rnf8(-/-p53(-/- cells displayed defective cell cycle checkpoints and DNA double-strand break repair. In addition, Rnf8(-/-p53(-/- mice had increased levels of genomic instability and a remarkably elevated tumor incidence compared to either Rnf8(-/- or p53(-/- mice. Altogether, the data in this study highlight the importance of p53-pathway activation upon loss of Rnf8, suggesting that Rnf8 and p53 functionally interact to protect against genomic instability and tumorigenesis.

  2. Angiogenin contributes to bladder cancer tumorigenesis by DNMT3b-mediated MMP2 activation.

    Science.gov (United States)

    Peres, Rafael; Furuya, Hideki; Pagano, Ian; Shimizu, Yoshiko; Hokutan, Kanani; Rosser, Charles J

    2016-07-12

    Epigenetic-mediated gene activation/silencing plays a crucial role in human tumorigenesis. Eliciting the underlying mechanism behind certain epigenetic changes is essential for understanding tumor biology. Previous studies in human cancers revealed an unrecognized interplay between Angiogenin (ANG) and matrix metalloproteinase-2 (MMP2) leading to pronounced tumorigenesis. Here we provide multiple lines of evidence further indicating ANG oncogenic potential. ANG expression resulted in the hypomethylated state of the MMP2 gene, which led to increased gene expression of MMP2. More than that, our global DNA methylation microarray analysis showed that gene manipulation of ANG affected a variety of pathways, such as cell migration, angiogenesis and specifically, tumor suppressor genes. Mechanistically, ANG negatively regulated DNA methyltransferase 3b (DNMT3b) enzymatic activity by down-regulating its expression and inhibiting its recruitment to the MMP2 promoter. Consistent with this, ANG-MMP2 overexpression and DNMT3b underexpression correlated with reduction in disease free survival of human bladder cancer patients. Together, the results continue to establish ANG as an oncoprotein and further reveal that ANG contributes to oncogenesis by the activation of MMP2 through modulation of DNMT3b functions.

  3. Rho-associated kinase (ROCK) function is essential for cell cycle progression, senescence and tumorigenesis.

    Science.gov (United States)

    Kümper, Sandra; Mardakheh, Faraz K; McCarthy, Afshan; Yeo, Maggie; Stamp, Gordon W; Paul, Angela; Worboys, Jonathan; Sadok, Amine; Jørgensen, Claus; Guichard, Sabrina; Marshall, Christopher J

    2016-01-14

    Rho-associated kinases 1 and 2 (ROCK1/2) are Rho-GTPase effectors that control key aspects of the actin cytoskeleton, but their role in proliferation and cancer initiation or progression is not known. Here, we provide evidence that ROCK1 and ROCK2 act redundantly to maintain actomyosin contractility and cell proliferation and that their loss leads to cell-cycle arrest and cellular senescence. This phenotype arises from down-regulation of the essential cell-cycle proteins CyclinA, CKS1 and CDK1. Accordingly, while the loss of either Rock1 or Rock2 had no negative impact on tumorigenesis in mouse models of non-small cell lung cancer and melanoma, loss of both blocked tumor formation, as no tumors arise in which both Rock1 and Rock2 have been genetically deleted. Our results reveal an indispensable role for ROCK, yet redundant role for isoforms 1 and 2, in cell cycle progression and tumorigenesis, possibly through the maintenance of cellular contractility.

  4. Autophagy-preferential degradation of MIR224 participates in hepatocellular carcinoma tumorigenesis.

    Science.gov (United States)

    Lan, Sheng-Hui; Wu, Shan-Ying; Zuchini, Roberto; Lin, Xi-Zhang; Su, Ih-Jen; Tsai, Ting-Fen; Lin, Yen-Ju; Wu, Cheng-Tao; Liu, Hsiao-Sheng

    2014-09-01

    Autophagy and microRNA (miRNA) are important regulators during cancer cell tumorigenesis. Impaired autophagy and high expression of the oncogenic microRNA MIR224 are prevalent in hepatocellular carcinoma (HCC); however, the relationship between the 2 phenomena remains elusive. In this study, we are the first to reveal that autophagy selectively regulates MIR224 expression through an autophagosome-mediated degradation system. Based on this finding, we further demonstrated that in hepatitis B virus (HBV)-related HCC, aberrant autophagy (low autophagic activity) results in accumulation of MIR224 and decreased expression of the target gene Smad4, which leads to increased cell migration and tumor formation. Preferential recruitment of MIR224 into the autophagosome was clearly demonstrated by a) miRNA in situ hybridization under confocal microscopy, and b) immunogold labeling of MIR224 under electron microscopy compared with a ubiquitously expressed microRNA MIRlet7e/let-7. Furthermore, we found that off-label use of amiodarone, an antiarrhythmic agent, effectively suppressed HCC tumorigenesis through autophagy-mediated MIR224 degradation both in vitro and in vivo. In summary, we identified amiodarone as a new autophagy inducer, which may provide an alternative approach in HCC therapy through a novel tumor suppression mechanism.

  5. Overexpression of Id1 in transgenic mice promotes mammary basal stem cell activity and breast tumorigenesis.

    Science.gov (United States)

    Shin, Dong-Hui; Park, Ji-Hye; Lee, Jeong-Yeon; Won, Hee-Young; Jang, Ki-Seok; Min, Kyueng-Whan; Jang, Si-Hyong; Woo, Jong-Kyu; Oh, Seung Hyun; Kong, Gu

    2015-07-10

    Inhibitor of differentiation/DNA binding (Id)1 is a crucial regulator of mammary development and breast cancer progression. However, its effect on stemness and tumorigenesis in mammary epithelial cells remains undefined. Herein, we demonstrate that Id1 induces mammary tumorigenesis by increasing normal and malignant mammary stem cell (MaSC) activities in transgenic mice. MaSC-enriched basal cell expansion and increased self-renewal and in vivo regenerative capacity of MaSCs are observed in the mammary glands of MMTV-Id1 transgenic mice. Furthermore, MMTV-Id1 mice develop ductal hyperplasia and mammary tumors with highly expressed basal markers. Id1 also increases breast cancer stem cell (CSC) population and activity in human breast cancer lines. Moreover, the effects of Id1 on normal and malignant stem cell activities are mediated by the Wnt/c-Myc pathway. Collectively, these findings provide in vivo genetic evidence of Id1 functions as an oncogene in breast cancer and indicate that Id1 regulates mammary basal stem cells by activating the Wnt/c-Myc pathway, thereby contributing to breast tumor development.

  6. Modulation of insulin degrading enzyme activity and liver cell proliferation.

    Science.gov (United States)

    Pivovarova, Olga; von Loeffelholz, Christian; Ilkavets, Iryna; Sticht, Carsten; Zhuk, Sergei; Murahovschi, Veronica; Lukowski, Sonja; Döcke, Stephanie; Kriebel, Jennifer; de las Heras Gala, Tonia; Malashicheva, Anna; Kostareva, Anna; Lock, Johan F; Stockmann, Martin; Grallert, Harald; Gretz, Norbert; Dooley, Steven; Pfeiffer, Andreas F H; Rudovich, Natalia

    2015-01-01

    Diabetes mellitus type 2 (T2DM), insulin therapy, and hyperinsulinemia are independent risk factors of liver cancer. Recently, the use of a novel inhibitor of insulin degrading enzyme (IDE) was proposed as a new therapeutic strategy in T2DM. However, IDE inhibition might stimulate liver cell proliferation via increased intracellular insulin concentration. The aim of this study was to characterize effects of inhibition of IDE activity in HepG2 hepatoma cells and to analyze liver specific expression of IDE in subjects with T2DM. HepG2 cells were treated with 10 nM insulin for 24 h with or without inhibition of IDE activity using IDE RNAi, and cell transcriptome and proliferation rate were analyzed. Human liver samples (n = 22) were used for the gene expression profiling by microarrays. In HepG2 cells, IDE knockdown changed expression of genes involved in cell cycle and apoptosis pathways. Proliferation rate was lower in IDE knockdown cells than in controls. Microarray analysis revealed the decrease of hepatic IDE expression in subjects with T2DM accompanied by the downregulation of the p53-dependent genes FAS and CCNG2, but not by the upregulation of proliferation markers MKI67, MCM2 and PCNA. Similar results were found in the liver microarray dataset from GEO Profiles database. In conclusion, IDE expression is decreased in liver of subjects with T2DM which is accompanied by the dysregulation of p53 pathway. Prolonged use of IDE inhibitors for T2DM treatment should be carefully tested in animal studies regarding its potential effect on hepatic tumorigenesis.

  7. Diet and Your Liver

    Science.gov (United States)

    ... and to do them for a long time. Eating an unhealthy diet can lead to liver disease. For example, ... and can help repair some liver damage. An unhealthy diet can make the liver ... diet include? • Eating foods from all the food groups: grains, proteins, ...

  8. Liver Tumors (For Parents)

    Science.gov (United States)

    ... Teaching Kids to Be Smart About Social Media Liver Tumors KidsHealth > For Parents > Liver Tumors Print A A A What's in this ... Malignant (Cancerous) Tumors Symptoms Diagnosis Treatment Coping The liver is the body's largest solid organ. Lying next ...

  9. Alcohol and liver

    Institute of Scientific and Technical Information of China (English)

    Natalia Osna

    2009-01-01

    @@ Liver is a primary site of ethanol metabolism, which makes this organ susceptible to alcohol-induced damage.Alcoholic liver disease (ALD) has many manifestations and complicated pathogenesis. In this Topic Highlight, we included the key reviews that characterize new findings about the mechanisms of ALD development and might be of strong interest for clinicians and researchers involved in liver alcohol studies.

  10. Research Areas: Liver Disease

    Science.gov (United States)

    ... and C, or by genetic mutations. Other liver diseases can be triggered by autoimmune reactions or drug toxicity. The rise in obesity in the United States has led to a rise in nonalcoholic fatty liver disease. Many liver diseases place individuals at higher risk ...

  11. LIVER AND BILIARY SYSTEM

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    9.1 Liver Function2007108 Blood pressure changes post liver transplantation in 206 recipients. LIU Hai(刘海),et al. 1st People′s Hosp, Shanghai Jiaotong Univ, Shanghai 200080. Chin J Cardiol 2006;34(10):902-904. Objective To study the blood pressure (BP)changes in the liver transplant recipients.

  12. Hepatic (Liver) Function Panel

    Science.gov (United States)

    ... 1- to 2-Year-Old Blood Test: Hepatic (Liver) Function Panel KidsHealth > For Parents > Blood Test: Hepatic (Liver) Function Panel Print A A A What's in ... Is The hepatic function panel, also known as liver function tests, is a group of seven tests ...

  13. LIVER AND BILIARY SYSTEM

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    9.1 Liver cirrhosis and fatty liver2003335 The effects of weight reduction in reversing fatty liver changes in overweight and obese patients.ZHU Huijuan(朱惠娟), et al.Dept Endocrinol, PUMC Hosp,CAMS & PUMC, Beijing 100730. Chin J Intern Med 2003:42(2):98-102.Objective:To study the effects of weight loss on non-

  14. Imaging in liver transplantation

    Institute of Scientific and Technical Information of China (English)

    Settimo Caruso; Roberto Miraglia; Luigi Maruzzelli; Salvatore Gruttadauria; Angelo Luca; Bruno Gridelli

    2009-01-01

    The aim of this study was to illustrate the role of noninvasive imaging tools such as ultrasonography, multidetector row computed tomography, and magnetic resonance imaging in the evaluation of pediatric and adult liver recipients and potential liver donors, and in the detection of potential complications arising from liver transplantation.

  15. LIVER AND BILIARY SYSTEM

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    11.1 Liver cirrhosis and fatty liver2003230 The relevance of fatty liver and insulin resistance. LIU Jun(刘军), et al. Dept Endocrinol, Zhong-shan Hosp, Fudan Univ, Shanghai 200032, Shanghai Med J 2003; 16(1): 14-17

  16. Multiple susceptibility loci for radiation-induced mammary tumorigenesis in F2[Dahl S x R]-intercross rats.

    Directory of Open Access Journals (Sweden)

    Victoria L Herrera

    Full Text Available Although two major breast cancer susceptibility genes, BRCA1 and BRCA2, have been identified accounting for 20% of breast cancer genetic risk, identification of other susceptibility genes accounting for 80% risk remains a challenge due to the complex, multi-factorial nature of breast cancer. Complexity derives from multiple genetic determinants, permutations of gene-environment interactions, along with presumptive low-penetrance of breast cancer predisposing genes, and genetic heterogeneity of human populations. As with other complex diseases, dissection of genetic determinants in animal models provides key insight since genetic heterogeneity and environmental factors can be experimentally controlled, thus facilitating the detection of quantitative trait loci (QTL. We therefore, performed the first genome-wide scan for loci contributing to radiation-induced mammary tumorigenesis in female F2-(Dahl S x R-intercross rats. Tumorigenesis was measured as tumor burden index (TBI after induction of rat mammary tumors at forty days of age via ¹²⁷Cs-radiation. We observed a spectrum of tumor latency, size-progression, and pathology from poorly differentiated ductal adenocarcinoma to fibroadenoma, indicating major effects of gene-environment interactions. We identified two mammary tumorigenesis susceptibility quantitative trait loci (Mts-QTLs with significant linkage: Mts-1 on chromosome-9 (LOD-2.98 and Mts-2 on chromosome-1 (LOD-2.61, as well as two Mts-QTLs with suggestive linkage: Mts-3 on chromosome-5 (LOD-1.93 and Mts-4 on chromosome-18 (LOD-1.54. Interestingly, Chr9-Mts-1, Chr5-Mts-3 and Chr18-Mts-4 QTLs are unique to irradiation-induced mammary tumorigenesis, while Chr1-Mts-2 QTL overlaps with a mammary cancer susceptibility QTL (Mcs 3 reported for 7,12-dimethylbenz-[α]antracene (DMBA-induced mammary tumorigenesis in F2[COP x Wistar-Furth]-intercross rats. Altogether, our results suggest at least three distinct susceptibility QTLs for

  17. Multiple susceptibility loci for radiation-induced mammary tumorigenesis in F2[Dahl S x R]-intercross rats.

    Science.gov (United States)

    Herrera, Victoria L; Ponce, Lorenz R; Ruiz-Opazo, Nelson

    2013-01-01

    Although two major breast cancer susceptibility genes, BRCA1 and BRCA2, have been identified accounting for 20% of breast cancer genetic risk, identification of other susceptibility genes accounting for 80% risk remains a challenge due to the complex, multi-factorial nature of breast cancer. Complexity derives from multiple genetic determinants, permutations of gene-environment interactions, along with presumptive low-penetrance of breast cancer predisposing genes, and genetic heterogeneity of human populations. As with other complex diseases, dissection of genetic determinants in animal models provides key insight since genetic heterogeneity and environmental factors can be experimentally controlled, thus facilitating the detection of quantitative trait loci (QTL). We therefore, performed the first genome-wide scan for loci contributing to radiation-induced mammary tumorigenesis in female F2-(Dahl S x R)-intercross rats. Tumorigenesis was measured as tumor burden index (TBI) after induction of rat mammary tumors at forty days of age via ¹²⁷Cs-radiation. We observed a spectrum of tumor latency, size-progression, and pathology from poorly differentiated ductal adenocarcinoma to fibroadenoma, indicating major effects of gene-environment interactions. We identified two mammary tumorigenesis susceptibility quantitative trait loci (Mts-QTLs) with significant linkage: Mts-1 on chromosome-9 (LOD-2.98) and Mts-2 on chromosome-1 (LOD-2.61), as well as two Mts-QTLs with suggestive linkage: Mts-3 on chromosome-5 (LOD-1.93) and Mts-4 on chromosome-18 (LOD-1.54). Interestingly, Chr9-Mts-1, Chr5-Mts-3 and Chr18-Mts-4 QTLs are unique to irradiation-induced mammary tumorigenesis, while Chr1-Mts-2 QTL overlaps with a mammary cancer susceptibility QTL (Mcs 3) reported for 7,12-dimethylbenz-[α]antracene (DMBA)-induced mammary tumorigenesis in F2[COP x Wistar-Furth]-intercross rats. Altogether, our results suggest at least three distinct susceptibility QTLs for irradiation

  18. Multiple Susceptibility Loci for Radiation-Induced Mammary Tumorigenesis in F2[Dahl S x R]-Intercross Rats

    Science.gov (United States)

    Herrera, Victoria L.; Ponce, Lorenz R.; Ruiz-Opazo, Nelson

    2013-01-01

    Although two major breast cancer susceptibility genes, BRCA1 and BRCA2, have been identified accounting for 20% of breast cancer genetic risk, identification of other susceptibility genes accounting for 80% risk remains a challenge due to the complex, multi-factorial nature of breast cancer. Complexity derives from multiple genetic determinants, permutations of gene-environment interactions, along with presumptive low-penetrance of breast cancer predisposing genes, and genetic heterogeneity of human populations. As with other complex diseases, dissection of genetic determinants in animal models provides key insight since genetic heterogeneity and environmental factors can be experimentally controlled, thus facilitating the detection of quantitative trait loci (QTL). We therefore, performed the first genome-wide scan for loci contributing to radiation-induced mammary tumorigenesis in female F2-(Dahl S x R)-intercross rats. Tumorigenesis was measured as tumor burden index (TBI) after induction of rat mammary tumors at forty days of age via 127Cs-radiation. We observed a spectrum of tumor latency, size-progression, and pathology from poorly differentiated ductal adenocarcinoma to fibroadenoma, indicating major effects of gene-environment interactions. We identified two mammary tumorigenesis susceptibility quantitative trait loci (Mts-QTLs) with significant linkage: Mts-1 on chromosome-9 (LOD-2.98) and Mts-2 on chromosome-1 (LOD-2.61), as well as two Mts-QTLs with suggestive linkage: Mts-3 on chromosome-5 (LOD-1.93) and Mts-4 on chromosome-18 (LOD-1.54). Interestingly, Chr9-Mts-1, Chr5-Mts-3 and Chr18-Mts-4 QTLs are unique to irradiation-induced mammary tumorigenesis, while Chr1-Mts-2 QTL overlaps with a mammary cancer susceptibility QTL (Mcs 3) reported for 7,12-dimethylbenz-[α]antracene (DMBA)-induced mammary tumorigenesis in F2[COP x Wistar-Furth]-intercross rats. Altogether, our results suggest at least three distinct susceptibility QTLs for irradiation

  19. Liver fatty acid binding protein (L-Fabp) modifies intestinal fatty acid composition and adenoma formation in ApcMin/+ mice

    OpenAIRE

    Dharmarajan, Sekhar; Newberry, Elizabeth P.; Montenegro, Grace; Nalbantoglu, ILKe; Davis, Victoria R.; Clanahan, Michael J.; Blanc, Valerie; Xie, Yan; Luo, Jianyang; Fleshman, James W.; Kennedy, Susan; Davidson, Nicholas O.

    2013-01-01

    Evidence suggests a relationship between dietary fat intake, obesity and colorectal cancer, implying a role for fatty acid (FA) metabolism in intestinal tumorigenesis that is incompletely understood. Liver fatty acid binding protein (L-Fabp), a dominant intestinal FA binding protein, regulates intestinal FA trafficking and metabolism and L-Fabp deletion attenuates diet-induced obesity. Here we examined whether changes in intestinal FA metabolism following L-Fabp deletion modify adenoma develo...

  20. Amebic liver abscess and polycystic liver disease

    Directory of Open Access Journals (Sweden)

    Karan V. S. Rana

    2013-01-01

    Full Text Available Polycystic liver disease is a rare disorder which remains asymptomatic. Infection of cyst is a major complication and is usually pyogenic. We report a rare case of amebic liver abscess in a patient with polycystic liver disease. In our search we found one such case report. Clinical features and radiological findings are usually sufficient, but atypical history and the presence of multiple hepatic abscesses in CT scan delayed diagnosis in our case. Histopathology of the cyst wall and enzyme immunoassay asserted the diagnosis.

  1. Liver abnormalities in pregnancy.

    Science.gov (United States)

    Than, Nwe Ni; Neuberger, James

    2013-08-01

    Abnormalities of liver function (notably rise in alkaline phosphatase and fall in serum albumin) are common in normal pregnancy, whereas rise in serum bilirubin and aminotransferase suggest either exacerbation of underlying pre-existing liver disease, liver disease related to pregnancy or liver disease unrelated to pregnancy. Pregnant women appear to have a worse outcome when infected with Hepatitis E virus. Liver diseases associated with pregnancy include abnormalities associated hyperemesis gravidarum, acute fatty liver disease, pre-eclampsia, cholestasis of pregnancy and HELLP syndrome. Prompt investigation and diagnosis is important in ensuring a successful maternal and foetal outcome. In general, prompt delivery is the treatment of choice for acute fatty liver, pre-eclampsia and HELLP syndrome and ursodeoxycholic acid is used for cholestasis of pregnancy although it is not licenced for this indication. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Ectopic expression of PTTG1/securin promotes tumorigenesis in human embryonic kidney cells

    Directory of Open Access Journals (Sweden)

    Malik Mohammed T

    2005-01-01

    Full Text Available Abstract Background Pituitary tumor transforming gene1 (PTTG1 is a novel oncogene that is expressed in most tumors. It encodes a protein that is primarily involved in the regulation of sister chromatid separation during cell division. The oncogenic potential of PTTG1 has been well characterized in the mouse, particularly mouse fibroblast (NIH3T3 cells, in which it induces cell proliferation, promotes tumor formation and angiogenesis. Human tumorigenesis is a complex and a multistep process often requiring concordant expression of a number of genes. Also due to differences between rodent and human cell biology it is difficult to extrapolate results from mouse models to humans. To determine if PTTG1 functions similarly as an oncogene in humans, we have characterized its effects on human embryonic kidney (HEK293 cells. Results We report that introduction of human PTTG1 into HEK293 cells through transfection with PTTG1 cDNA resulted in increased cell proliferation, anchorage-independent growth in soft agar, and formation of tumors after subcutaneous injection of nu/nu mice. Pathologic analysis revealed that these tumors were poorly differentiated. Both analysis of HEK293 cells transiently transfected with PTTG1 cDNA and analysis of tumors developed on injection of HEK293 cells that had been stably transfected with PTTG1 cDNA indicated significantly higher levels of secretion and expression of bFGF, VEGF and IL-8 compared to HEK293 cells transfected with pcDNA3.1 vector or uninvolved tissues collected from the mice. Mutation of the proline-rich motifs at the C-terminal of PTTG1 abolished its oncogenic properties. Mice injected with this mutated PTTG1 either did not form tumors or formed very small tumors. Taken together our results suggest that PTTG1 is a human oncogene that possesses the ability to promote tumorigenesis in human cells at least in part through the regulation of expression or secretion of bFGF, VEGF and IL-8. Conclusions Our results

  3. Clinicopathologic and gene expression parameters predict liver cancer prognosis

    Directory of Open Access Journals (Sweden)

    Hao Ke

    2011-11-01

    Full Text Available Abstract Background The prognosis of hepatocellular carcinoma (HCC varies following surgical resection and the large variation remains largely unexplained. Studies have revealed the ability of clinicopathologic parameters and gene expression to predict HCC prognosis. However, there has been little systematic effort to compare the performance of these two types of predictors or combine them in a comprehensive model. Methods Tumor and adjacent non-tumor liver tissues were collected from 272 ethnic Chinese HCC patients who received curative surgery. We combined clinicopathologic parameters and gene expression data (from both tissue types in predicting HCC prognosis. Cross-validation and independent studies were employed to assess prediction. Results HCC prognosis was significantly associated with six clinicopathologic parameters, which can partition the patients into good- and poor-prognosis groups. Within each group, gene expression data further divide patients into distinct prognostic subgroups. Our predictive genes significantly overlap with previously published gene sets predictive of prognosis. Moreover, the predictive genes were enriched for genes that underwent normal-to-tumor gene network transformation. Previously documented liver eSNPs underlying the HCC predictive gene signatures were enriched for SNPs that associated with HCC prognosis, providing support that these genes are involved in key processes of tumorigenesis. Conclusion When applied individually, clinicopathologic parameters and gene expression offered similar predictive power for HCC prognosis. In contrast, a combination of the two types of data dramatically improved the power to predict HCC prognosis. Our results also provided a framework for understanding the impact of gene expression on the processes of tumorigenesis and clinical outcome.

  4. Obesity and Liver Cancer.

    Science.gov (United States)

    Aleksandrova, Krasimira; Stelmach-Mardas, Marta; Schlesinger, Sabrina

    Obesity and related metabolic disorders have become globally prevalent posing a challenge for the chronically damaged liver and predisposing the development and progression of cancer. The rising phenomenon of "obesity epidemic" may provide means for understanding why liver cancer is one of the few malignancies with rising incidence in developed countries over the last decades. Non-alcoholic fatty liver disease associated with obesity, insulin resistance, and type 2 diabetes is an increasingly recognized trigger for liver cancer in Western populations characterized by low prevalence of established risk factors for liver cancer such as viral hepatitis and hepatotoxin exposure. Accumulating evidence has established an association between higher body mass index as an indicator of general obesity and higher risk of primary liver cancer. The associations are stronger in men, in patients with underlying liver disease and in white ethnic groups. Abdominal obesity, weight gain in adult life and metabolic factors related to visceral fat accumulation were also suggested as important risk factors for liver cancer; however, more studies are needed to evaluate these associations. The association of obesity and metabolic parameters with liver cancer survival remains controversial. It is unclear which exact mechanisms could provide links between obesity and liver cancer risk. Recent evidence has implicated several molecular pathways in obesity-associated liver cancer. These include insulin resistance leading to increased levels of insulin and insulin-like growth factors, chronic inflammation, adipose tissue remodeling, pro-inflammatory cytokine and adipokine secretion, and altered gut microbiota. These mechanisms coincide with inflammatory and metabolic processes occurring in non-alcoholic fatty liver disease predisposing cancer development and progression. In the context of the current evidence, better understanding of the role of obesity and related metabolic factors may help in

  5. Calcium sensing receptor suppresses human pancreatic tumorigenesis through a novel NCX1/Ca(2+)/β-catenin signaling pathway.

    Science.gov (United States)

    Tang, Bo; Chow, Jimmy Y C; Dong, Tobias Xiao; Yang, Shi-Ming; Lu, De-Sheng; Carethers, John M; Dong, Hui

    2016-07-10

    The calcium sensing receptor (CaSR) is functionally expressed in normal human pancreases, but its pathological role in pancreatic tumorigenesis is currently unknown. We sought to investigate the role of CaSR in pancreatic cancer (PC) and the underlying molecular mechanisms. We revealed that the expression of CaSR was consistently downregulated in the primary cancer tissues from PC patients, which was correlated with tumor size, differentiation and poor survival of the patients. CaSR activation markedly suppressed pancreatic tumorigenesis in vitro and in vivo likely through the Ca(2+) entry mode of Na(+)/Ca(2+) exchanger 1 (NCX1) to induce Ca(2+) entry into PC cells. Moreover, NCX1-mediated Ca(2+) entry resulted in Ca(2+)-dependent inhibition of β-catenin signaling in PC cells, eventually leading to the inhibition of pancreatic tumorigenesis. Collectively, we demonstrate for the first time that CaSR exerts a suppressive function in pancreatic tumorigenesis through a novel NCX1/Ca(2+)/β-catenin signaling pathway. Targeting this specific signaling pathway could be a potential therapeutic strategy for PC.

  6. Breast cancer cell behaviors on staged tumorigenesis-mimicking matrices derived from tumor cells at various malignant stages.

    Science.gov (United States)

    Hoshiba, Takashi; Tanaka, Masaru

    2013-09-20

    Extracellular matrix (ECM) has been focused to understand tumor progression in addition to the genetic mutation of cancer cells. Here, we prepared "staged tumorigenesis-mimicking matrices" which mimic in vivo ECM in tumor tissue at each malignant stage to understand the roles of ECM in tumor progression. Breast tumor cells, MDA-MB-231 (invasive), MCF-7 (non-invasive), and MCF-10A (benign) cells, were cultured to form their own ECM beneath the cells and formed ECM was prepared as staged tumorigenesis-mimicking matrices by decellularization treatment. Cells showed weak attachment on the matrices derived from MDA-MB-231 cancer cells. The proliferations of MDA-MB-231 and MCF-7 was promoted on the matrices derived from MDA-MB-231 cancer cells whereas MCF-10A cell proliferation was not promoted. MCF-10A cell proliferation was promoted on the matrices derived from MCF-10A cells. Chemoresistance of MDA-MB-231 cells against 5-fluorouracil increased on only matrices derived from MDA-MB-231 cells. Our results showed that the cells showed different behaviors on staged tumorigenesis-mimicking matrices according to the malignancy of cell sources for ECM preparation. Therefore, staged tumorigenesis-mimicking matrices might be a useful in vitro ECM models to investigate the roles of ECM in tumor progression.

  7. Control of Nutrient Stress-Induced Metabolic Reprogramming by PKCζ in Tumorigenesis

    Science.gov (United States)

    Ma, Li; Tao, Yongzhen; Duran, Angeles; Llado, Victoria; Galvez, Anita; Barger, Jennifer F.; Castilla, Elias A.; Chen, Jing; Yajima, Tomoko; Porollo, Aleksey; Medvedovic, Mario; Brill, Laurence M.; Plas, David R.; Riedl, Stefan J.; Leitges, Michael; Diaz-Meco, Maria T.; Richardson, Adam D.; Moscat, Jorge

    2013-01-01

    SUMMARY Tumor cells have high-energetic and anabolic needs and are known to adapt their metabolism to be able to survive and keep proliferating under conditions of nutrient stress. We show that PKCζ deficiency promotes the plasticity necessary for cancer cells to reprogram their metabolism to utilize glutamine through the serine biosynthetic pathway in the absence of glucose. PKCζ represses the expression of two key enzymes of the pathway, PHGDH and PSAT1, and phosphorylates PHGDH at key residues to inhibit its enzymatic activity. Interestingly, the loss of PKCζ in mice results in enhanced intestinal tumorigenesis and increased levels of these two metabolic enzymes, whereas patients with low levels of PKCζ have a poor prognosis. Furthermore, PKCζ and caspase-3 activities are correlated with PHGDH levels in human intestinal tumors. Taken together, this demonstrates that PKCζ is a critical metabolic tumor suppressor in mouse and human cancer. PMID:23374352

  8. Over-expression of ST3Gal-I promotes mammary tumorigenesis

    DEFF Research Database (Denmark)

    Picco, Gianfranco; Julien, Sylvain; Brockhausen, Inka

    2010-01-01

    3Gal-I adds sialic acid to the galactose residue of core 1 (Galbeta1,3GalNAc) O-glycans and this enzyme is over-expressed in breast cancer resulting in the expression of sialylated core 1 glycans. In order to study the role of ST3Gal-I in mammary tumor development, we developed transgenic mice...... and lactating mammary glands, the stomach, lungs and intestine. Although no obvious defects were observed in the fully developed mammary gland, when these mice were crossed with PyMT mice, a highly significant decrease in tumor latency was observed compared to the PyMT mice on an identical background....... These results indicate that ST3Gal-I is acting as a tumor promoter in this model of breast cancer. This, we believe, is the first demonstration that over-expression of a glycosyltransferase involved in mucin-type O-linked glycosylation can promote tumorigenesis....

  9. Morgana/chp-1, a ROCK inhibitor involved in centrosome duplication and tumorigenesis.

    Science.gov (United States)

    Ferretti, Roberta; Palumbo, Valeria; Di Savino, Augusta; Velasco, Silvia; Sbroggiò, Mauro; Sportoletti, Paolo; Micale, Lucia; Turco, Emilia; Silengo, Lorenzo; Palumbo, Gioacchino; Hirsch, Emilio; Teruya-Feldstein, Julie; Bonaccorsi, Silvia; Pandolfi, Pier Paolo; Gatti, Maurizio; Tarone, Guido; Brancaccio, Mara

    2010-03-16

    Centrosome abnormalities lead to genomic instability and are a common feature of many cancer cells. Here we show that mutations in morgana/chp-1 result in centrosome amplification and lethality in both Drosophila and mouse, and that the fly centrosome phenotype is fully rescued by the human ortholog of morgana. In mouse cells, morgana forms a complex with Hsp90 and ROCK I and II, and directly binds ROCK II. Morgana downregulation promotes the interaction between ROCK II and nucleophosmin (NPM), leading to an increased ROCK II kinase activity, which results in centrosome amplification. Morgana(+/-) primary cells and mice display an increased susceptibility to neoplastic transformation. In addition, tumor tissue array histochemical analysis revealed that morgana is underexpressed in a large fraction of breast and lung human cancers. Thus, morgana/chp-1 appears to prevent both centrosome amplification and tumorigenesis. Copyright 2010 Elsevier Inc. All rights reserved.

  10. IKKα Promotes Intestinal Tumorigenesis by Limiting Recruitment of M1-like Polarized Myeloid Cells

    Directory of Open Access Journals (Sweden)

    Serkan I. Göktuna

    2014-06-01

    Full Text Available The recruitment of immune cells into solid tumors is an essential prerequisite of tumor development. Depending on the prevailing polarization profile of these infiltrating leucocytes, tumorigenesis is either promoted or blocked. Here, we identify IκB kinase α (IKKα as a central regulator of a tumoricidal microenvironment during intestinal carcinogenesis. Mice deficient in IKKα kinase activity are largely protected from intestinal tumor development that is dependent on the enhanced recruitment of interferon γ (IFNγ-expressing M1-like myeloid cells. In IKKα mutant mice, M1-like polarization is not controlled in a cell-autonomous manner but, rather, depends on the interplay of both IKKα mutant tumor epithelia and immune cells. Because therapies aiming at the tumor microenvironment rather than directly at the mutated cancer cell may circumvent resistance development, we suggest IKKα as a promising target for colorectal cancer (CRC therapy.

  11. Selenium and sulindac are synergistic to inhibit intestinal tumorigenesis in Apc/p21 mice

    Directory of Open Access Journals (Sweden)

    Bi Xiuli

    2013-01-01

    Full Text Available Abstract Background Both selenium and non-steroidal anti-inflammatory drug (NSAID sulindac are effective in cancer prevention, but their effects are affected by several factors including epigenetic alterations and gene expression. The current study was designed to determine the effects of the combination of selenium and sulindac on tumor inhibition and the underlying mechanisms. Results We fed the intestinal tumor model Apc/p21 mice with selenium- and sulindac-supplemented diet for 24 weeks, and found that the combination of selenium and sulindac significantly inhibited intestinal tumorigenesis, in terms of reducing tumor incidence by 52% and tumor multiplicities by 80% (p Conclusions The selenium is synergistic with sulindac to exert maximal effects on tumor inhibition. This finding provides an important chemopreventive strategy using combination of anti-cancer agents, which has a great impact on cancer prevention and has a promising translational potential.

  12. The Role of HPV in Head and Neck Cancer Stem Cell Formation and Tumorigenesis

    Directory of Open Access Journals (Sweden)

    Mark S. Swanson

    2016-02-01

    Full Text Available The cancer stem cell (CSC theory proposes that a minority of tumor cells are capable of self-replication and tumorigenesis. It is these minority of cells that are responsible for cancer metastasis and recurrence in head and neck squamous cell cancers (HNSCC. Human papilloma virus (HPV-related cancer of the oropharynx is becoming more prevalent, which makes understanding of the relationship between HPV and CSCs more important than ever. This relationship is critical because CSC behavior can be predicted based on cell surface markers, which makes them a suitable candidate for targeted therapy. New therapies are an exciting opportunity to advance past the stalled outcomes in HNSCC that have plagued patients and clinicians for several decades.

  13. Tumor suppression by miR-26 overrides potential oncogenic activity in intestinal tumorigenesis

    Science.gov (United States)

    Zeitels, Lauren R.; Acharya, Asha; Shi, Guanglu; Chivukula, Divya; Chivukula, Raghu R.; Anandam, Joselin L.; Abdelnaby, Abier A.; Balch, Glen C.; Mansour, John C.; Yopp, Adam C.; Richardson, James A.

    2014-01-01

    Down-regulation of miR-26 family members has been implicated in the pathogenesis of multiple malignancies. In some settings, including glioma, however, miR-26-mediated repression of PTEN promotes tumorigenesis. To investigate the contexts in which the tumor suppressor versus oncogenic activity of miR-26 predominates in vivo, we generated miR-26a transgenic mice. Despite measureable repression of Pten, elevated miR-26a levels were not associated with malignancy in transgenic animals. We documented reduced miR-26 expression in human colorectal cancer and, accordingly, showed that miR-26a expression potently suppressed intestinal adenoma formation in Apcmin/+ mice, a model known to be sensitive to Pten dosage. These studies reveal a tumor suppressor role for miR-26 in intestinal cancer that overrides putative oncogenic activity, highlighting the therapeutic potential of miR-26 delivery to this tumor type. PMID:25395662

  14. Correlation of the nuclear accumulation of CTNNB1 and colonic tumorigenesis

    Institute of Scientific and Technical Information of China (English)

    QIU Zhe-fu; Maruyama Keiji; HAN De-min; Nakamura Satoshi

    2006-01-01

    @@ CTNNB1 (or beta-catenin) is regarded as a central effecter in molecules of the wingless/Wnt signalling pathway. It is a key component of the cadherin mediated cell to cell adhesion system and forms a complex with the protein product of adenomatous polyposis coli (APC), glycogen synthase kinase 3β (GSK3β) and conductin.1 One mutation of APC is also responsible for activation of wingless/Wnt signalling pathway and accumulation of free beta-catenin in the cell. Beta-catenin upregulates oncogenes, such as cyclin D1 and c-myc.2 Beta-catenin expression in cytoplasm and nuclei was reported to increase in many cases of intestinal tumorigenesis.3,4 In addition, the hyperexpression of integrin linked kinase (ILK) in colonic polyposis has been demonstrated.5

  15. Brain diseases and tumorigenesis: The good and bad cops of pentraxin3.

    Science.gov (United States)

    Fornai, Francesco; Carrizzo, Albino; Ferrucci, Michela; Damato, Antonio; Biagioni, Francesca; Gaglione, Anderson; Puca, Annibale Alessandro; Vecchione, Carmine

    2015-12-01

    The prototype of long pentraxins, Pentraxin 3 (PTX3), is an evolutionarily conserved multifunctional, pattern-recognition protein constituted by a cyclic multimeric structure. PTX3 interacts with a variety of ligands, such as growth factors, extracellular matrix components, molecules of the complement cascade, pathogens recognition proteins, angiogenetic and adhesion molecules. PTX3 could be considered as a molecular link between innate and adaptive immunity as well as between focal and circulating responses during inflammation. In fact, it modulates the functions of resident dendritic cells and circulating lymphocytes. Recent evidence demonstrates that manipulation of PTX3 may produce even opposite effects depending on which target organ is considered and the physiopathological context. In the present review we discuss the good and bad cops of PTX3 concerning multifacted effects on inflammation, innate immunity, brain diseases and tumorigenesis. Finally, a perspective on PTX3 and autophagy is provided as a convergent pathway.

  16. Nonmetabolic functions of pyruvate kinase isoform M2 in controlling cell cycle progression and tumorigenesis

    Institute of Scientific and Technical Information of China (English)

    Zhimin Lu

    2012-01-01

    Pyruvate kinase catalyzes the rate-limiting final step of glycolysis,generating adenosine triphosphate (ATP) and pyruvate.The M2 tumor-specific isoform of pyruvate kinase (PKM2) promotes glucose uptake and lactate production in the presence of oxygen,known as aerobic glycolysis or the Warburg effect.As recently reported in Nature,PKM2,besides its metabolic function,has a nonmetabolic function in the direct control of cell cycle progression by activating β-catenin and inducing expression of the β-catenin downstream gene CCND1 (encoding for cyclin D1).This nonmetabolic function of PKM2 is essential for epidermal growth factor receptor (EGFR) activation-induced tumorigenesis.

  17. Prepubertal exposure to cow's milk reduces susceptibility to carcinogen-induced mammary tumorigenesis in rats

    DEFF Research Database (Denmark)

    Nielsen, Tina Skau; Khan, Galam; Davis, Jennifer

    2011-01-01

    Cow's milk contains high levels of estrogens, progesterone and insulin-like growth factor 1 (IGF-1), all of which are associated with breast cancer. We investigated whether prepubertal milk exposure affects mammary gland development and carcinogenesis in rats. Sprague-Dawley rats were given either...... whole milk or tap water to drink from postnatal day (PND) 14 to PND 35, and thereafter normal tap water. Mammary tumorigenesis was induced by administering 7,12-dimethylbenz[a]anthracene on PND 50. Milk exposure increased circulating E2 levels on PND 25 by 10-fold (p vaginal...... or apoptosis were seen. IGF-1 mRNA levels were reduced on PND 50 in the mammary glands of rats exposed to milk at puberty. Our results suggest that drinking milk before puberty reduces later risk of developing mammary cancer in rats. This might be mediated by a reduction in the number of TEBs and lower...

  18. Hepatocytes isolated from neoplastic liver-immunomagnetic purging as a new source for transplantation

    Institute of Scientific and Technical Information of China (English)

    Aravin Gunasegaram; Javed Akhter; Peng Yao; Loreena A Johnson; Stephen M Riodan; David L Morris

    2008-01-01

    AIM: To investigate whether hepatocytes isolated from macroscopically normal liver during hepatic resection for neoplasia could provide a novel source of healthy hepatocytes, including the development of reliable protocols for malignant cells removal from the hepatocyte preparation.METHODS: Hepatocytes were procured from resected liver of 18 patients with liver tumors using optimised digestion and cell-enrichment protocols. Suspensions of various known quantities of the HT-29 tumor cell line and patient hepatocytes were treated or not with Ep-CAM-antibody-coated immunomagnetic beads in order to investigate the efficacy of tumor-purging by immunomagnetic depletion, using a semi-quantitative RT-PCR method developed to detect tumor cells.Immunomagnetic bead-treated or bead-untreated tumor cell-hepatocyte suspensions were transplanted intra-peritoneally in Balb/C nude mice to assess the rates of tumor development.RESULTS: Mean viable hepatocyte yield was 9.3 x 106 cells per gram of digested liver with mean viability of 70.5%. Immunomagnetic depletion removed tumor cells to below the RT-PCR detection-threshold of 1 tumor cell in 106 hepatocytes, representing a maximum tumor purging efficacy of greater than 400000-fold.Transplanted, immunomagnetic bead-purged tumor cell-hepatocyte suspensions did not form peritoneal tumors in Balb/C nude mice. Co-transplantation of hepatocytes with tumor cells did not increase tumorigenesis of the tumor cells.CONCLUSION: Immunomagnetic depletion appears to be an effective method of purging contaminating tumor cells to below threshold for likely tumorigenesis.Along with improved techniques for isolation of large numbers of viable hepatocytes, normal liver resected for neoplasia has potential as another clinically useful source of hepatocytes for transplantation.

  19. Suppression of tumorigenesis in mitochondrial NADP(+)-dependent isocitrate dehydrogenase knock-out mice.

    Science.gov (United States)

    Kim, Seontae; Kim, Sung Youl; Ku, Hyeong Jun; Jeon, Yong Hyun; Lee, Ho Won; Lee, Jaetae; Kwon, Taeg Kyu; Park, Kwon Moo; Park, Jeen-Woo

    2014-02-01

    The tumor host microenvironment is increasingly viewed as an important contributor to tumor growth and suppression. Cellular oxidative stress resulting from high levels of reactive oxygen species (ROS) contributes to various processes involved in the development and progress of malignant tumors including carcinogenesis, aberrant growth, metastasis, and angiogenesis. In this regard, the stroma induces oxidative stress in adjacent tumor cells, and this in turn causes several changes in tumor cells including modulation of the redox status, inhibition of cell proliferation, and induction of apoptotic or necrotic cell death. Because the levels of ROS are determined by a balance between ROS generation and ROS detoxification, disruption of this system will result in increased or decreased ROS level. Recently, we demonstrated that the control of mitochondrial redox balance and cellular defense against oxidative damage is one of the primary functions of mitochondrial NADP(+)-dependent isocitrate dehydrogenase (IDH2) that supplies NADPH for antioxidant systems. To explore the interactions between tumor cells and the host, we evaluated tumorigenesis between IDH2-deficient (knock-out) and wild-type mice in which B16F10 melanoma cells had been implanted. Suppression of B16F10 cell tumorigenesis was reproducibly observed in the IDH2-deficient mice along with significant elevation of oxidative stress in both the tumor and the stroma. In addition, the expression of angiogenesis markers was significantly down-regulated in both the tumor and the stroma of the IDH2-deficient mice. These results support the hypothesis that redox status-associated changes in the host environment of tumor-bearing mice may contribute to cancer progression.

  20. ∆DNMT3B4-del Contributes to Aberrant DNA Methylation Patterns in Lung Tumorigenesis

    Directory of Open Access Journals (Sweden)

    Mark Z. Ma

    2015-10-01

    Full Text Available Aberrant DNA methylation is a hallmark of cancer but mechanisms contributing to the abnormality remain elusive. We have previously shown that ∆DNMT3B is the predominantly expressed form of DNMT3B. In this study, we found that most of the lung cancer cell lines tested predominantly expressed DNMT3B isoforms without exons 21, 22 or both 21 and 22 (a region corresponding to the enzymatic domain of DNMT3B termed DNMT3B/∆DNMT3B-del. In normal bronchial epithelial cells, DNMT3B/ΔDNMT3B and DNMT3B/∆DNMT3B-del displayed equal levels of expression. In contrast, in patients with non-small cell lung cancer NSCLC, 111 (93% of the 119 tumors predominantly expressed DNMT3B/ΔDNMT3B-del, including 47 (39% tumors with no detectable DNMT3B/∆DNMT3B. Using a transgenic mouse model, we further demonstrated the biological impact of ∆DNMT3B4-del, the ∆DNMT3B-del isoform most abundantly expressed in NSCLC, in global DNA methylation patterns and lung tumorigenesis. Expression of ∆DNMT3B4-del in the mouse lungs resulted in an increased global DNA hypomethylation, focal DNA hypermethylation, epithelial hyperplastia and tumor formation when challenged with a tobacco carcinogen. Our results demonstrate ∆DNMT3B4-del as a critical factor in developing aberrant DNA methylation patterns during lung tumorigenesis and suggest that ∆DNMT3B4-del may be a target for lung cancer prevention.

  1. N-cadherin promotes thyroid tumorigenesis through modulating major signaling pathways.

    Science.gov (United States)

    Da, Chenxing; Wu, Kexia; Yue, Chenli; Bai, Peisong; Wang, Rong; Wang, Guanjie; Zhao, Man; Lv, Yanyan; Hou, Peng

    2017-01-31

    Epithelial-mesenchymal transition (EMT), a crucial step in disease progression, plays a key role in tumor metastasis. N-cadherin, a well-known EMT marker, acts as a major oncogene in diverse cancers, whereas its functions in thyroid cancer remains largely unclear. This study was designed to explore the biological roles and related molecular mechanism of N-cadherin in thyroid tumorigenesis. Quantitative RT-PCR (qRT-PCR) and immunohistochemistry assays were used to evaluate N-cadherin expression. A series of in vitro studies such as cell proliferation, colony formation, cell cycle, apoptosis, migration and invasion assays were performed to determine the effect of N-cadherin on malignant behavior of thyroid cancer cells. Our results showed that N-cadherin was significantly upregulated in papillary thyroid cancers (PTCs) as compared with non-cancerous thyroid tissues. N-cadherin knockdown markedly inhibited cell proliferation, colony formation, cell migration and invasion, and induced cell cycle arrest and apoptosis. On the other hand, ectopic expression of N-cadherin promoted thyroid cancer cell growth and invasiveness. Mechanically, our data demonstrated that tumor-promoting role of N-cadherin in thyroid cancer was closely related to the activities of the MAPK/Erk, the phosphatidylinositol-3-kinase (PI3K)/Akt and p16/Rb signaling pathways in addition to affecting the EMT process. Altogether, our findings suggest that N-cadherin promotes thyroid tumorigenesis by modulating the activities of major signaling pathways and EMT process, and may represent a potential therapeutic target for this cancer.

  2. The p53 inhibitor MDM2 facilitates Sonic Hedgehog-mediated tumorigenesis and influences cerebellar foliation.

    Directory of Open Access Journals (Sweden)

    Reem Malek

    Full Text Available Disruption of cerebellar granular neuronal precursor (GNP maturation can result in defects in motor coordination and learning, or in medulloblastoma, the most common childhood brain tumor. The Sonic Hedgehog (Shh pathway is important for GNP proliferation; however, the factors regulating the extent and timing of GNP proliferation, as well as GNP differentiation and migration are poorly understood. The p53 tumor suppressor has been shown to negatively regulate the activity of the Shh effector, Gli1, in neural stem cells; however, the contribution of p53 to the regulation of Shh signaling in GNPs during cerebellar development has not been determined. Here, we exploited a hypomorphic allele of Mdm2 (Mdm2(puro, which encodes a critical negative regulator of p53, to alter the level of wild-type MDM2 and p53 in vivo. We report that mice with reduced levels of MDM2 and increased levels of p53 have small cerebella with shortened folia, reminiscent of deficient Shh signaling. Indeed, Shh signaling in Mdm2-deficient GNPs is attenuated, concomitant with decreased expression of the Shh transducers, Gli1 and Gli2. We also find that Shh stimulation of GNPs promotes MDM2 accumulation and enhances phosphorylation at serine 166, a modification known to increase MDM2-p53 binding. Significantly, loss of MDM2 in Ptch1(+/- mice, a model for Shh-mediated human medulloblastoma, impedes cerebellar tumorigenesis. Together, these results place MDM2 at a major nexus between the p53 and Shh signaling pathways in GNPs, with key roles in cerebellar development, GNP survival, cerebellar foliation, and MB tumorigenesis.

  3. FHL2 silencing reduces Wnt signaling and osteosarcoma tumorigenesis in vitro and in vivo.

    Directory of Open Access Journals (Sweden)

    Julia Brun

    Full Text Available BACKGROUND: The molecular mechanisms that are involved in the growth and invasiveness of osteosarcoma, an aggressive and invasive primary bone tumor, are not fully understood. The transcriptional co-factor FHL2 (four and a half LIM domains protein 2 acts as an oncoprotein or as a tumor suppressor depending on the tissue context. In this study, we investigated the role of FHL2 in tumorigenesis in osteosarcoma model. METHODOLOGY/PRINCIPAL FINDINGS: Western blot analyses showed that FHL2 is expressed above normal in most human and murine osteosarcoma cells. Tissue microarray analysis revealed that FHL2 protein expression is high in human osteosarcoma and correlates with osteosarcoma aggressiveness. In murine osteosarcoma cells, FHL2 silencing using shRNA decreased canonical Wnt/β-catenin signaling and reduced the expression of Wnt responsive genes as well as of the key Wnt molecules Wnt5a and Wnt10b. This effect resulted in inhibition of osteosarcoma cell proliferation, invasion and migration in vitro. Using xenograft experiments, we showed that FHL2 silencing markedly reduced tumor growth and lung metastasis occurence in mice. The anti-oncogenic effect of FHL2 silencing in vivo was associated with reduced cell proliferation and decreased Wnt signaling in the tumors. CONCLUSION/SIGNIFICANCE: Our findings demonstrate that FHL2 acts as an oncogene in osteosarcoma cells and contributes to tumorigenesis through Wnt signaling. More importantly, FHL2 depletion greatly reduces tumor cell growth and metastasis, which raises the potential therapeutic interest of targeting FHL2 to efficiently impact primary bone tumors.

  4. Tumorigenesis and spontaneous metastasis by luciferase-labeled human xenograft osteosarcoma cells in nude mice.

    Science.gov (United States)

    Du, Lin; Xu, Wen-ting; Fan, Qi-ming; Tu, Bing; Shen, Yang; Yan, Wei; Tang, Ting-ting; Wang, You

    2012-11-01

    Osteosarcoma (OS) is the most common primary malignant tumor of bone. Mouse models of human OS can invariably provide greater insight into the complex mechanisms that underlie the development and pathogenesis of this aggressive tumor. Bioluminescence technology favored tracing cancer cells in vivo. In this study, an OS model was described and evaluated using human OS cell line, Saos2, labeled with luciferase (Saos2-luc). Saos2 cells were infected by lentivirus loading a firefly luciferase gene. Luciferase expression of Saos2-luc cells was characterized both in vitro and in vivo. Specific biologic and oncologic features of Saos2-luc cells were analyzed. The OS was established as orthotopic xenografts in nude mice. Both orthotopic tumors and spontaneous lung metastasis were analyzed. Tumorigenesis and spontaneous lung metastasis in nude mice could be monitored in vivo through in vivo imaging system. The enhancement in proliferation, migration and invasion abilities and the attenuation in adhesion ability were observed in Saos2-luc cells compared with Saos2 cells. Furthermore, there were the up-regulation of Osteocalcin, CCR10, CXCR1 and ID1 and the down-regulation of ALP, collagen I, CCR1, CCR3, CXCR3, NID and N-cadherin in Saos2-luc cells compare to Saos2 cells. The rate of spontaneous lung metastasis in Saos2-luc cells was higher than that in Saos2 cells, although without significant difference. Lentivirus transfection may cause alteration of gene expression profiles and further biological functions. This model can be used in the elucidation of molecular mechanisms of tumorigenesis and the screening of new therapeutic agents.

  5. Deficiency of pRb family proteins and p53 in invasive urothelial tumorigenesis.

    Science.gov (United States)

    He, Feng; Mo, Lan; Zheng, Xiao-Yong; Hu, Changkun; Lepor, Herbert; Lee, Eva Y-H P; Sun, Tung-Tien; Wu, Xue-Ru

    2009-12-15

    Defects in pRb tumor suppressor pathway occur in approximately 50% of the deadly muscle-invasive urothelial carcinomas in humans and urothelial carcinoma is the most prevalent epithelial cancer in long-term survivors of hereditary retinoblastomas caused by loss-of-function RB1 mutations. Here, we show that conditional inactivation of both RB1 alleles in mouse urothelium failed to accelerate urothelial proliferation. Instead, it profoundly activated the p53 pathway, leading to extensive apoptosis, and selectively induced pRb family member p107. Thus, pRb loss triggered multiple fail-safe mechanisms whereby urothelial cells evade tumorigenesis. Additional loss of p53 in pRb-deficient urothelial cells removed these p53-dependent tumor barriers, resulting in late-onset hyperplasia, umbrella cell nuclear atypia, and rare-occurring low-grade, superficial papillary bladder tumors, without eliciting invasive carcinomas. Importantly, mice deficient in both pRb and p53, but not those deficient in either protein alone, were highly susceptible to subthreshold carcinogen exposure and developed invasive urothelial carcinomas that strongly resembled the human counterparts. The invasive lesions had a marked reduction of p107 but not p130 of the pRb family. Our data provide compelling evidence, indicating that urothelium, one of the slowest cycling epithelia, is remarkably resistant to transformation by pRb or p53 deficiency; that concurrent loss of these two tumor suppressors is necessary but insufficient to initiate urothelial tumorigenesis along the invasive pathway; that p107 may play a critical role in suppressing invasive urothelial tumor formation; and that replacing/restoring the function of pRb, p107, or p53 could be explored as a potential therapeutic strategy to block urothelial tumor progression.

  6. The role of formyl peptide receptor 1 (FPR1) in neuroblastoma tumorigenesis.

    Science.gov (United States)

    Snapkov, Igor; Öqvist, Carl Otto; Figenschau, Yngve; Kogner, Per; Johnsen, John Inge; Sveinbjørnsson, Baldur

    2016-07-18

    Formyl peptide receptor 1 (FPR1) is a G protein-coupled receptor mainly expressed by the cells of myeloid origin, where it mediates the innate immune response to bacterial formylated peptides. High expression of FPR1 has been detected in various cancers but the function of FPR1 in tumorigenesis is poorly understood. Expression of FPR1 in neuroblastoma cell lines and primary tumors was studied using RT-PCR, western blotting, immunofluorescence and immunohistochemistry. Calcium mobilization assays and western blots with phospho-specific antibodies were used to assess the functional activity of FPR1 in neuroblastoma. The tumorigenic capacity of FPR1 was assessed by xenografting of neuroblastoma cells expressing inducible FPR1 shRNA, FPR1 cDNA or control shRNA in nude mice. FPR1 is expressed in neuroblastoma primary tumors and cell lines. High expression of FPR1 corresponds with high-risk disease and poor patient survival. Stimulation of FPR1 in neuroblastoma cells using fMLP, a selective FPR1 agonist, induced intracellular calcium mobilization and activation of MAPK/Erk, PI3K/Akt and P38-MAPK signal transduction pathways that were inhibited by using Cyclosporin H, a selective receptor antagonist for FPR1. shRNA knock-down of FPR1 in neuroblastoma cells conferred a delayed xenograft tumor development in nude mice, whereas an ectopic overexpression of FPR1 promoted augmented tumorigenesis in nude mice. Our data demonstrate that FPR1 is involved in neuroblastoma development and could represent a therapy option for the treatment of neuroblastoma.

  7. Dietary selenium deficiency exacerbates DSS-induced epithelial injury and AOM/DSS-induced tumorigenesis.

    Directory of Open Access Journals (Sweden)

    Caitlyn W Barrett

    Full Text Available Selenium (Se is an essential micronutrient that exerts its functions via selenoproteins. Little is known about the role of Se in inflammatory bowel disease (IBD. Epidemiological studies have inversely correlated nutritional Se status with IBD severity and colon cancer risk. Moreover, molecular studies have revealed that Se deficiency activates WNT signaling, a pathway essential to intestinal stem cell programs and pivotal to injury recovery processes in IBD that is also activated in inflammatory neoplastic transformation. In order to better understand the role of Se in epithelial injury and tumorigenesis resulting from inflammatory stimuli, we examined colonic phenotypes in Se-deficient or -sufficient mice in response to dextran sodium sulfate (DSS-induced colitis, and azoxymethane (AOM followed by cyclical administration of DSS, respectively. In response to DSS alone, Se-deficient mice demonstrated increased morbidity, weight loss, stool scores, and colonic injury with a concomitant increase in DNA damage and increases in inflammation-related cytokines. As there was an increase in DNA damage as well as expression of several EGF and TGF-β pathway genes in response to inflammatory injury, we sought to determine if tumorigenesis was altered in the setting of inflammatory carcinogenesis. Se-deficient mice subjected to AOM/DSS treatment to model colitis-associated cancer (CAC had increased tumor number, though not size, as well as increased incidence of high grade dysplasia. This increase in tumor initiation was likely due to a general increase in colonic DNA damage, as increased 8-OHdG staining was seen in Se-deficient tumors and adjacent, non-tumor mucosa. Taken together, our results indicate that Se deficiency worsens experimental colitis and promotes tumor development and progression in inflammatory carcinogenesis.

  8. Corruption of homeostatic mechanisms in the guanylyl cyclase C signaling pathway underlying colorectal tumorigenesis

    Science.gov (United States)

    Waldman, Scott A

    2010-01-01

    Colon cancer, the second leading cause of cancer-related mortality worldwide, originates from the malignant transformation of intestinal epithelial cells. The intestinal epithelium undergoes a highly organized process of rapid regeneration along the crypt-villus axis, characterized by proliferation, migration, differentiation and apoptosis, whose coordination is essential to maintaining the mucosal barrier. Disruption of these homeostatic processes predisposes cells to mutations in tumor suppressors or oncogenes, whose dysfunction provides transformed cells an evolutionary growth advantage. While sequences of genetic mutations at different stages along the neoplastic continuum have been established, little is known of the events initiating tumorigenesis prior to adenomatous polyposis coli (APC) mutations. Here, we examine a role for the corruption of homeostasis induced by silencing novel tumor suppressors, including the intestine-specific transcription factor CDX2 and its gene target guanylyl cyclase C (GCC), as early events predisposing cells to mutations in APC and other sequential genes that initiate colorectal cancer. CDX2 and GCC maintain homeostatic regeneration in the intestine by restricting cell proliferation, promoting cell maturation and adhesion, regulating cell migration and defending the intestinal barrier and genomic integrity. Elimination of CDX2 or GCC promotes intestinal tumor initiation and growth in aged mice, mice carrying APC mutations or mice exposed to carcinogens. The roles of CDX2 and GCC in suppressing intestinal tumorigenesis, universal disruption in their signaling through silencing of hormones driving GCC, and the uniform overexpression of GCC by tumors underscore the potential value of oral replacement with GCC ligands as targeted prevention and therapy for colorectal cancer. PMID:20592492

  9. Rewiring drug-activated p53-regulatory network from suppressing to promoting tumorigenesis

    Institute of Scientific and Technical Information of China (English)

    Wei Song; Jiguang Wang; Ying Yang; Naihe Jing; Xiangsun Zhang; Luonan Chen; Jiarui Wu

    2012-01-01

    Many of oncogenes and tumor suppressor genes have been found to exert variable and even opposing roles in different kinds of tumors or at different stages of cancer development.Here we showed that tumorigenic potential of mouse embryonic carcinoma P19 cells cultured in adherent plates (attached-P19-cells) was suppressed by a chemotherapeutic agent,5-aza-2'-deoxycytidine (ZdCyd),whereas the higher pro-tumorigenicity of P19 cells growing in suspension (detached-P19-cells) was generated by the ZdCyd treatment.Surprisingly,p53 activity was highly up-regulated by ZdCyd in both growing conditions.By our developed computational approaches,we revealed that there was a significant enrichment of apoptotic pathways in the ZdCyd-induced p53-dominant gene-regulatory network in attached P19 cells,whereas the pro-survival genes were significantly enriched in the ZdCyd-induced p53 network in detached P19 cells.The protein-protein interaction network of the ZdCyd-treated detached P19 cells was significantly different from that of ZdCyd-treated attached P19 cells.On the other hand,inhibition of pS3 expression by siRNA suppressed the ZdCyd-induced tumorigenesis of detached P19 cells,suggesting that the ZdCyd-activated p53 plays oncogenic function in detached P19 cells.Taken together,these results indicate a context-dependent role for the ZdCyd-activated p53-dominant network in tumorigenesis.

  10. Distribution of LGR5+ cells and associated implications during the early stage of gastric tumorigenesis.

    Directory of Open Access Journals (Sweden)

    Bo Gun Jang

    Full Text Available Lgr5 was identified as a promising gastrointestinal tract stem cell marker in mice. Lineage tracing indicates that Lgr5(+ cells may not only be the cells responsible for the origin of tumors; they may also be the so-called cancer stem cells. In the present study, we investigated the presence of Lgr5(+ cells and their biological significance in normal human gastric mucosa and gastric tumors. RNAscope, a newly developed RNA in situ hybridization technique, specifically labeled Lgr5(+ cells at the basal glands of the gastric antrum. Notably, the number of Lgr5(+ cells was remarkably increased in intestinal metaplasia. In total, 76% of gastric adenomas and 43% of early gastric carcinomas were positive for LGR5. Lgr5(+ cells were found more frequently in low-grade tumors with active Wnt signaling and an intestinal gland type, suggesting that LGR5 is likely involved in the very early stages of Wnt-driven tumorigenesis in the stomach. Interestingly, similar to stem cells in normal tissues, Lgr5(+ cells were often restricted to the base of the tumor glands, and such Lgr5(+ restriction was associated with high levels of intestinal stem cell markers such as EPHB2, OLFM4, and ASCL2. Thus, our findings show that Lgr5(+ cells are present at the base of the antral glands in the human stomach and that this cell population significantly expands in intestinal metaplasias. Furthermore, Lgr5(+ cells are seen in a large number of gastric tumors ; their frequent basal arrangements and coexpression of ISC markers support the idea that Lgr5(+ cells act as stem cells during the early stage of intestinal-type gastric tumorigenesis.

  11. PTEN encoding product: a marker for tumorigenesis and progression of gastric carcinoma

    Institute of Scientific and Technical Information of China (English)

    Lin Yang; Li-Ge Kuang; Hua-Chuan Zheng; Jin-Yi Li; Dong-Ying Wu; Su-Min Zhang; Yan Xin

    2003-01-01

    AIM: To detect the expression of PTEN encoding productin normal mucosa, intestinal metaplasia (IM), dysplasia andcarcinoma of the stomach, and to investigate its clinicalimplication in tumorigenesis and progression of gastriccarcinoma.METHODS: Formalin-fixed paraffin embedded specimens from184 cases of gastric carcinoma, their adjacent normal mucosa,IM and dysplasia were evaluated for PTEN protein expressionby SABC immunohistochemistry. PTEN expression wascompared with tumor stage, lymph node metastasis, Lauren'sand WHO's histological classification of gastric carcinoma.Expression of VEGF was also detected in 60 cases of gastriccarcinoma and its correlation with PTEN was concerned.RESULTS: The positive rates of PTEN protein were 100 %(102/102), 98.5 %(65/66), 66.7 % (4/6) and 47.8 %(88/184)in normal mucosa, IM, dysplasia and carcinoma of the stomach,respectively. The positive rates in dysplasia and carcinomawere lower than in normal mucosa and IM (P<0.01).Advanced gastric cancers expressed less frequent PTEN thanearly gastric cancer (42.9 % v567.6 %, P<0.01). The positiverate of PTEN protein was lower in gastric cancer with thanwithout lymph node metastasis (40.3 % v563.3 %, P<0.01).PTEN was less expressed in diffuse-type than in intestinal-type gastric cancer (41.5 % v557.8 %,P<0.05). Signet ringcell carcinoma showed the expression of PTEN at the lowestlevel (25.0 %, 7/28); less than well and moderatelydifferentiated ones (P<0.01). Expression of PTEN was notcorrelated with expression of VEGF (P>0.05).CONCLUSION: Loss or reduced expression of PTEN proteinoccures commonly in tumorigenesis and progression of gastriccarcinoma. It is suggested that PTEN can be an objective markerfor pathologically biological behaviors of gastric carcinoma.

  12. Deletion of Forkhead Box M1 transcription factor from respiratory epithelial cells inhibits pulmonary tumorigenesis.

    Directory of Open Access Journals (Sweden)

    I-Ching Wang

    Full Text Available The Forkhead Box m1 (Foxm1 protein is induced in a majority of human non-small cell lung cancers and its expression is associated with poor prognosis. However, specific requirements for the Foxm1 in each cell type of the cancer lesion remain unknown. The present study provides the first genetic evidence that the Foxm1 expression in respiratory epithelial cells is essential for lung tumorigenesis. Using transgenic mice, we demonstrated that conditional deletion of Foxm1 from lung epithelial cells (epFoxm1(-/- mice prior to tumor initiation caused a striking reduction in the number and size of lung tumors, induced by either urethane or 3-methylcholanthrene (MCA/butylated hydroxytoluene (BHT. Decreased lung tumorigenesis in epFoxm1(-/- mice was associated with diminished proliferation of tumor cells and reduced expression of Topoisomerase-2alpha (TOPO-2alpha, a critical regulator of tumor cell proliferation. Depletion of Foxm1 mRNA in cultured lung adenocarcinoma cells significantly decreased TOPO-2alpha mRNA and protein levels. Moreover, Foxm1 directly bound to and induced transcription of the mouse TOPO-2alpha promoter region, indicating that TOPO-2alpha is a direct target of Foxm1 in lung tumor cells. Finally, we demonstrated that a conditional deletion of Foxm1 in pre-existing lung tumors dramatically reduced tumor growth in the lung. Expression of Foxm1 in respiratory epithelial cells is critical for lung cancer formation and TOPO-2alpha expression in vivo, suggesting that Foxm1 is a promising target for anti-tumor therapy.

  13. A Requirement for SOCS-1 and SOCS-3 Phosphorylation in Bcr-Abl-Induced Tumorigenesis

    Directory of Open Access Journals (Sweden)

    Xiaoxue Qiu

    2012-06-01

    Full Text Available Suppressors of cytokine signaling 1 and 3 (SOCS-1 and SOCS-3 are inhibitors of the Janus tyrosine kinase (JAK/signal transducers and activators of transcription (STAT pathway and function in a negative feedback loop during cytokine signaling. Abl transformation is associated with constitutive activation of JAK/STAT-dependent signaling. However, the mechanism by which Abl oncoproteins bypass SOCS inhibitory regulation remains poorly defined. Here, we demonstrate that coexpression of Bcr-Abl with SOCS-1 or SOCS-3 results in tyrosine phosphorylation of these SOCS proteins. Interestingly, SOCS-1 is highly tyrosine phosphorylated in one of five primary chronic myelogenous leukemia samples. Bcr-Abl-dependent tyrosine phosphorylation of SOCS-1 and SOCS-3 occurs mainly on Tyr 155 and Tyr 204 residues of SOCS-1 and on Tyr 221 residue of SOCS-3. We observed that phosphorylation of these SOCS proteins was associated with their binding to Bcr-Abl. Bcr-Abl-dependent phosphorylation of SOCS-1 and SOCS-3 diminished their inhibitory effects on the activation of JAK and STAT5 and thereby enhanced JAK/STAT5 signaling. Strikingly, disrupting the tyrosine phosphorylation of SOCS-1 or SOCS-3 impaired the expression of Bcl-XL protein and sensitized K562 leukemic cells to undergo apoptosis. Moreover, selective mutation of tyrosine phosphorylation sites of SOCS-1 or SOCS-3 significantly blocked Bcr-Abl-mediated tumorigenesis in nude mice and inhibited Bcr-Abl-mediated murine bone marrow transformation. Together, these results reveal a mechanism of how Bcr-Abl may overcome SOCS-1 and SOCS-3 inhibition to constitutively activate the JAK/STAT-dependent signaling, and suggest that Bcr-Abl may critically requires tyrosine phosphorylation of SOCS-1 and SOCS-3 to mediate tumorigenesis when these SOCS proteins are present in cells.

  14. Loss of RASSF1A synergizes with deregulated RUNX2 signaling in tumorigenesis.

    Science.gov (United States)

    van der Weyden, Louise; Papaspyropoulos, Angelos; Poulogiannis, George; Rust, Alistair G; Rashid, Mamunur; Adams, David J; Arends, Mark J; O'Neill, Eric

    2012-08-01

    The tumor suppressor gene RASSF1A is inactivated through point mutation or promoter hypermethylation in many human cancers. In this study, we conducted a Sleeping Beauty transposon-mediated insertional mutagenesis screen in Rassf1a-null mice to identify candidate genes that collaborate with loss of Rassf1a in tumorigenesis. We identified 10 genes, including the transcription factor Runx2, a transcriptional partner of Yes-associated protein (YAP1) that displays tumor suppressive activity through competing with the oncogenic TEA domain family of transcription factors (TEAD) for YAP1 association. While loss of RASSF1A promoted the formation of oncogenic YAP1-TEAD complexes, the combined loss of both RASSF1A and RUNX2 further increased YAP1-TEAD levels, showing that loss of RASSF1A, together with RUNX2, is consistent with the multistep model of tumorigenesis. Clinically, RUNX2 expression was frequently downregulated in various cancers, and reduced RUNX2 expression was associated with poor survival in patients with diffuse large B-cell or atypical Burkitt/Burkitt-like lymphomas. Interestingly, decreased expression levels of RASSF1 and RUNX2 were observed in both precursor T-cell acute lymphoblastic leukemia and colorectal cancer, further supporting the hypothesis that dual regulation of YAP1-TEAD promotes oncogenic activity. Together, our findings provide evidence that loss of RASSF1A expression switches YAP1 from a tumor suppressor to an oncogene through regulating its association with transcription factors, thereby suggesting a novel mechanism for RASSF1A-mediated tumor suppression. ©2012 AACR.

  15. Dose and Spatial Effects in Long-Distance Radiation Signaling In Vivo: Implications for Abscopal Tumorigenesis

    Energy Technology Data Exchange (ETDEWEB)

    Mancuso, Mariateresa, E-mail: mariateresa.mancuso@enea.it [Laboratory of Radiation Biology and Biomedicine, Agenzia Nazionale per le Nuove Tecnologie, l' Energia e lo Sviluppo Economico Sostenibile (ENEA) Centro Ricerche Casaccia, Rome (Italy); Giardullo, Paola [Guglielmo Marconi University, Rome (Italy); Leonardi, Simona [Laboratory of Radiation Biology and Biomedicine, Agenzia Nazionale per le Nuove Tecnologie, l' Energia e lo Sviluppo Economico Sostenibile (ENEA) Centro Ricerche Casaccia, Rome (Italy); Pasquali, Emanuela [Guglielmo Marconi University, Rome (Italy); Casciati, Arianna [Laboratory of Radiation Biology and Biomedicine, Agenzia Nazionale per le Nuove Tecnologie, l' Energia e lo Sviluppo Economico Sostenibile (ENEA) Centro Ricerche Casaccia, Rome (Italy); De Stefano, Ilaria [Guglielmo Marconi University, Rome (Italy); Tanori, Mirella; Pazzaglia, Simonetta [Laboratory of Radiation Biology and Biomedicine, Agenzia Nazionale per le Nuove Tecnologie, l' Energia e lo Sviluppo Economico Sostenibile (ENEA) Centro Ricerche Casaccia, Rome (Italy); Saran, Anna, E-mail: anna.saran@enea.it [Laboratory of Radiation Biology and Biomedicine, Agenzia Nazionale per le Nuove Tecnologie, l' Energia e lo Sviluppo Economico Sostenibile (ENEA) Centro Ricerche Casaccia, Rome (Italy)

    2013-03-01

    Purpose: To investigate the dose and spatial dependence of abscopal radiation effects occurring in vivo in the mouse, along with their tumorigenic potential in the central nervous system (CNS) of a radiosensitive mouse model. Methods and Materials: Patched1 (Ptch1){sup +/−} mice, carrying a germ-line heterozygous inactivating mutation in the Ptch1 gene and uniquely susceptible to radiation damage in neonatal cerebellum, were exposed directly to ionizing radiation (1, 2, or 3 Gy of x-rays) or treated in a variety of partial-body irradiation protocols, in which the animals' head was fully protected by suitable lead cylinders while the rest of the body was exposed to x-rays in full or in part. Apoptotic cell death was measured in directly irradiated and shielded cerebellum shortly after irradiation, and tumor development was monitored in lifetime groups. The same endpoints were measured using different shielding geometries in mice irradiated with 3 or 10 Gy of x-rays. Results: Although dose-dependent cell death was observed in off-target cerebellum for all doses and shielding conditions tested, a conspicuous lack of abscopal response for CNS tumorigenesis was evident at the lowest dose of 1 Gy. By changing the amount of exposed body volume, the shielding geometry could also significantly modulate tumorigenesis depending on dose. Conclusions: We conclude that interplay between radiation dose and exposed tissue volume plays a critical role in nontargeted effects occurring in mouse CNS under conditions relevant to humans. These findings may help understanding the mechanisms of long-range radiation signaling in harmful effects, including carcinogenesis, occurring in off-target tissues.

  16. [Liver and sport].

    Science.gov (United States)

    Watelet, J

    2008-11-01

    The liver is a vital organ and plays a central role in energy exchange, protein synthesis as well as the elimination of waste products from the body. Acute and chronic injury may disturb a variety of liver functions to different degrees. Over the last three decades, the effects of physical activity and competitive sport on the liver have been described by various investigators. These include viral hepatitis and drug-induced liver disorders. Herein, we review acute and chronic liver diseases potentially caused by sport. Team physicians, trainers and others, responsible for the health of athletes, should be familiar with the risk factors, clinical features, and consequences of liver diseases that occur in sports.

  17. Endovascular management in liver transplantation

    Institute of Scientific and Technical Information of China (English)

    Kyu-Bo Sung

    2006-01-01

    @@ Liver transplantation was developed for the treatment of hepatic failure, and the first human liver transplantation was done in 1963. From the 1990 s,liver transplantation was generally accepted as a treatment modality for both end-stage liver disease and selected liver malignancies. Initially, liver transplantation was started with deceased donor whole-size liver transplantation (whole-size LT) as in other organ transplantation, but there is now a shortage of deceased liver donors has occurred. As a solution, deceased donor split liver transplantation (split LT) began in 1989 and living donor liver transplantation (LDLT) in the early 1990 s. Current liver transplantation techniques include whole-size LT, reduced-size liver transplantation (reduced-size LT), split LT and single or dual LDLT. Two donors give a part of their livers to one adult recipient simultaneously in dual LDLT.

  18. Transjugular liver biopsy.

    Science.gov (United States)

    Ble, Michel; Procopet, Bogdan; Miquel, Rosa; Hernandez-Gea, Virginia; García-Pagán, Juan Carlos

    2014-11-01

    Liver biopsy is still the gold standard for evaluation of acute and chronic liver diseases, despite achievements regarding noninvasive diagnosis and staging in liver diseases. Transjugular liver biopsy (TJLB) has proved a good option when ascites and/or significant coagulopathy precludes a percutaneous approach. Because diagnostic hemodynamic procedures can be performed during the same session, it is useful in many clinical settings, regardless of the absence of percuteaneous contraindications. TJLB is a safe technique able to provide good-quality specimens with a low rate of complications. This article presents an overview of TJLB that discusses the technique, applicability, indications, contraindications, complications, and diagnostic accuracy.

  19. Prohemostatic Interventions in Liver Surgery

    NARCIS (Netherlands)

    Stellingwerff, Menno; Brandsma, Amarins; Lisman, Ton; Porte, Robert J.

    Surgical procedures of the liver, such as partial liver resections and liver transplantation, are major types of abdominal surgery. Liver surgery can be associated with excessive intraoperative blood loss, not only because the liver is a highly vascularized organ, but also because it plays a central

  20. Liver transplantation in polycystic liver disease

    DEFF Research Database (Denmark)

    Krohn, Paul S; Hillingsø, Jens; Kirkegaard, Preben

    2008-01-01

    OBJECTIVE: Polycystic liver disease (PLD) is a rare, hereditary, benign disorder. Hepatic failure is uncommon and symptoms are caused by mass effects leading to abdominal distension and pain. Liver transplantation (LTX) offers fully curative treatment, but there is still some controversy about...... whether it is a relevant modality considering the absence of liver failure, relative organ shortage, perioperative risks and lifelong immunosuppression. The purpose of this study was to review our experience of LTX for PLD and to compare the survival with the overall survival of patients who underwent LTX....../kidney transplantation. One patient had undergone kidney transplantation 10 years earlier. RESULTS: Median follow-up was 55 months. One patient who underwent combined transplantation died after 5.4 months because of multiorgan failure after re-LTX, and one patient, with well-functioning grafts, died of lymphoma after 7...

  1. Estabishment of A Human Liver Cancer Cell Line Transfected with IL-2 cDNA and Its Biologic Activity

    Institute of Scientific and Technical Information of China (English)

    孙跃明; 王学浩; 杜竞辉

    2001-01-01

    Objective To obtain IL-2 gene transfected human liver cancer cells and study IL-2 expression and its biologic activity in vivo. Methods Human liver cancer cells SMMC-7721 were cocultured with recombinant retroviral vector LNC-IL-2,and screening was performed in G418 medium.The exogenous IL-2 cDNA at the DNA,RNA,and protein levels were determined by using dot hybridization,PR-PCR and MTT methods respectively.The tumorigenesis and antitumorigenesis of the screened liver cancer cell with subcutaneous injection in nude mice were observed. Results and Conclusion The IL-2 cDNA was successfully integrated into SMMC-7721 cell genomic DNA and continuously expressed for more than 88 days.Subcutaneous vaccination of the nude mice with transfected cells revealed an obvious suppression of its tumorigenicity,and could induce antitumor activity in vivo.

  2. Hypoxia and fatty liver.

    Science.gov (United States)

    Suzuki, Tomohiro; Shinjo, Satoko; Arai, Takatomo; Kanai, Mai; Goda, Nobuhito

    2014-11-07

    The liver is a central organ that metabolizes excessive nutrients for storage in the form of glycogen and lipids and supplies energy-producing substrates to the peripheral tissues to maintain their function, even under starved conditions. These processes require a considerable amount of oxygen, which causes a steep oxygen gradient throughout the hepatic lobules. Alcohol consumption and/or excessive food intake can alter the hepatic metabolic balance drastically, which can precipitate fatty liver disease, a major cause of chronic liver diseases worldwide, ranging from simple steatosis, through steatohepatitis and hepatic fibrosis, to liver cirrhosis. Altered hepatic metabolism and tissue remodeling in fatty liver disease further disrupt hepatic oxygen homeostasis, resulting in severe liver hypoxia. As master regulators of adaptive responses to hypoxic stress, hypoxia-inducible factors (HIFs) modulate various cellular and organ functions, including erythropoiesis, angiogenesis, metabolic demand, and cell survival, by activating their target genes during fetal development and also in many disease conditions such as cancer, heart failure, and diabetes. In the past decade, it has become clear that HIFs serve as key factors in the regulation of lipid metabolism and fatty liver formation. This review discusses the molecular mechanisms by which hypoxia and HIFs regulate lipid metabolism in the development and progression of fatty liver disease.

  3. Acute liver failure

    DEFF Research Database (Denmark)

    Bernal, William; Lee, William M; Wendon, Julia

    2015-01-01

    Over the last three decades acute liver failure (ALF) has been transformed from a rare and poorly understood condition with a near universally fatal outcome, to one with a well characterized phenotype and disease course. Complex critical care protocols are now applied and emergency liver...

  4. Prolactin and liver disease

    NARCIS (Netherlands)

    A.G.C. Bauer (Alexander)

    1982-01-01

    textabstractCirrhosis of the liver is associated with profound endocrinological disturbances. Until recently it was thought that these disturbances were caused mainly by ineffective elimination of hormones by the diseased liver. It is now known that the pathogenesis of disturbed hormonal function in

  5. Bioartificial Liver Support

    Directory of Open Access Journals (Sweden)

    Vincent G Bain

    2001-01-01

    Full Text Available Bioartificial liver support has been increasingly the focus of both basic and clinical research in an attempt to replicate the multiplicity of normal liver function. The concept is attractive because, if it is effective, patients with acute liver failure may be supported until native liver regeneration occurs or, by optimizing their condition, until liver transplantation is possible. Current bioartificial liver support systems utilize primary porcine hepatocytes or transformed human hepatocytes, which are housed within a bioreactor, through which the patient's blood or plasma is pumped in an extracorporeal circuit. The optimal source for the hepatocytes is an area of debate; however, a genetically engineered cell line may provide optimal function. Novel three-dimensional matrices that anchor the hepatocytes are being designed to mimic architectural features of the normal liver. Large multicentre, randomized, controlled trials are ongoing following several pilot studies. Serious side effects such as hemodynamic instability and immune reactions have been infrequent. Much controversy, however, surrounds the issue of possible transmission of pig endogenous retrovirus to humans, and current trials are being carefully monitored. Bioartificial liver support is a promising technology, and the results of current and planned studies are awaited with great interest.

  6. Fatigue after Liver Transplantation

    NARCIS (Netherlands)

    B.T.J. van Ginneken (Berbke)

    2009-01-01

    textabstractLiver transplantation (LTx) has developed from an experimental procedure in the 1960’s to the preferred treatment for end-stage liver disease nowadays. The first human LTx was performed by Starlz and his team in 1963 in Colorado.[1] Unfortunately, this patient died within a few days. The

  7. Liver and Biliary System

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    2011220 Value of liver biopsy in diagnosis of chronic hepatitis B. YANG Fang(杨方) ,et al. 2nd Ward, Shenyang 6th People’s Hosp,Shenyang 110006. Chin J Infect Dis 2011; 29(2):99-103. Objective To explore the value of liver biopsy in diagnosis of the severity of chronic hepatitis

  8. Multiple pyogenic liver abscess

    Institute of Scientific and Technical Information of China (English)

    Mabrouk Bahloul; Anis Chaari; Nadia Bouaziz-Khlaf; Hatem Kallel; Leila Herguefi; Hedi Chelly; Chokri Ben Hamida; Mounir Bouaziz

    2006-01-01

    Multiple pyogenic liver abscesses have been rarely described. We report a fatal case of multiple pyogenic liver abscesses affecting a 38-year-old woman requiring surgical drainage. Evolution was marked by occurrence of a septic shock with multi-organ system failure. The patient died 48 h after surgery. Causes, therapeutics and outcome of the disease are discussed.

  9. Liver and Biliary System

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    9.1.Liver cirrhosis and fatty liver2005376 The role of ribosomal S6 kinase in thepathogenesis of rat hepatic fibrosis.YANG Miaofang(杨妙芳),et al.Dept Gastroenterol,Changzheng Hosp,2nd Milit Med Univ,Shanghai 200003.Chin J Dig 2005;25(2):98-100.

  10. LIVER AND BILIARGY SYSTEM

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    8.1 Liver cirrhosis and fatty liver2004100 The clinical feature and prognosis of Aero-monas septicaemia in hepatic cirrhosis: a report of 50 cases. QU Fen (曲芬), et al. Clin Centre, 302nd Hosp PLA, Beijing 100039. Chin J Intern Med 2003; 42 (12): 840 - 846Objective: Aeromonas septicaemia complicating cirrhosis

  11. Alcohol-Related Liver Disease

    Science.gov (United States)

    ... A Life After Diagnosis Support for Chronic Illness Corporate Partnerships Interview with Kristen Hanks Liver Lowdown July ... stomach • enlarged spleen • brain disorders and coma • kidney failure • liver cancer In addition alcoholic liver disease may ...

  12. [Xenotransplantation of the liver].

    Science.gov (United States)

    Winkler, M; Schlitt, H J

    1999-01-01

    The development of pigs transgenic for human regulators of complement activation resulted in the nearly total elimination of episodes of hyperacute rejection following discordant solid organ xenotransplantation. Following discordant heart or kidney transplantation, in subhuman primates, graft survival rates of up to several months can be observed. In contrast to these organs, the xenotransplantation of the liver is associated with the inherent problem of the immunological and metabolic compatibility of the large variety of xenoproteins generated. Based on a review of data mainly derived from experimental ex-vivo xenoliver perfusions in patients with hepatic coma, whole organ orthotopic or heterotopic liver xenotransplantation currently is not likely to become a relevant option for the treatment of patients with endstage liver failure. In contrast, clinical studies utilizing different forms of bioartificial liver assist devices are currently underway. Based on preliminary data published, this form of liver support therapy might enter the clinic in the near future.

  13. Liver cancer oncogenomics

    DEFF Research Database (Denmark)

    Marquardt, Jens U; Andersen, Jesper B

    2015-01-01

    Primary liver cancers are among the most rapidly evolving malignant tumors worldwide. An underlying chronic inflammatory liver disease, which precedes liver cancer development for several decades and frequently creates a pro-oncogenic microenvironment, impairs progress in therapeutic approaches....... Molecular heterogeneity of liver cancer is potentiated by a crosstalk between epithelial tumor and stromal cells that complicate translational efforts to unravel molecular mechanisms of hepatocarcinogenesis with a drugable intend. Next-generation sequencing has greatly advanced our understanding of cancer...... development. With regards to liver cancer, the unprecedented coverage of next-generation sequencing has created a detailed map of genetic alterations and identified key somatic changes such as CTNNB1 and TP53 as well as several previously unrecognized recurrent disease-causing alterations that could...

  14. Sorafenib treatment during partial hepatectomy reduces tumorgenesis in an inflammation-associated liver cancer model

    Science.gov (United States)

    Salmon, Asher; Peretz, Tamar; Galun, Eithan; Axelrod, Jonathan H.; Sonnenblick, Amir

    2016-01-01

    The long-term prognosis after resection of hepatocellular carcinoma (HCC), which is one of the treatment options for early-stage HCC, remains unsatisfactory as a result of a high incidence of disease recurrence. Recent studies performed in murine models revealed a link between liver regeneration under chronic inflammation and hepatic tumorigenesis. Sorafenib is a potent drug for advanced HCC with multikinase inhibition activity. We propose that inhibition of signal transduction pathways which are activated during hepatectomy, using Sorafenib, will reduce accelerated tumorigenesis. To test this hypothesis, we studied the Mdr2-knockout (KO) mouse strain, a model of inflammation-associated cancer, which underwent partial hepatectomy (PHx) at three months of age, with or without Sorafenib. Here we show that Sorafenib treatment during PHx inhibited different signal transduction pathways at the multikinase levels, but did not result in increased morbidity or mortality. At the early stages after PHx, Sorafenib treatment had no effect on the course of proliferation, apoptosis and DNA repair in the regenerating liver, but resulted in decreased stellate cells activation and inflammatory response. Finally, we show that Sorafenib treatment during PHx at three months of age resulted in decreased fibrosis and tumor formation at 8.5 months. In conclusion our study indicates that short-term Sorafenib treatment during PHx is safe and effective in inhibiting inflammation-associated cancer, and is therefore a potential strategy for recurrence prevention in patients with early-stage HCC treated with PHx. PMID:26695439

  15. Liver hyperplasia after tamoxifen induction of Myc in a transgenic medaka model

    Directory of Open Access Journals (Sweden)

    Luciana A. Menescal

    2012-07-01

    Myc is a global transcriptional regulator and one of the most frequently overexpressed oncoproteins in human tumors. It is well established that activation of Myc leads to enhanced cell proliferation but can also lead to increased apoptosis. The use of animal models expressing deregulated levels of Myc has helped to both elucidate its function in normal cells and give insight into how Myc initiates and maintains tumorigenesis. Analyses of the medaka (Oryzias latipes genome uncovered the unexpected presence of two Myc gene copies in this teleost species. Comparison of these Myc versions to other vertebrate species revealed that one gene, myc17, differs by the loss of some conserved regulatory protein motifs present in all other known Myc genes. To investigate how such differences might affect the basic biological functions of Myc, we generated a tamoxifen-inducible in vivo model utilizing a natural, fish-specific Myc gene. Using this model we show that, when activated, Myc17 leads to increased proliferation and to apoptosis in a dose-dependent manner, similar to human Myc. We have also shown that long-term Myc17 activation triggers liver hyperplasia in adult fish, allowing this newly established transgenic medaka model to be used to study the transition from hyperplasia to liver cancer and to identify Myc-induced tumorigenesis modifiers.

  16. Arsenic-induced Aurora-A activation contributes to chromosome instability and tumorigenesis

    Science.gov (United States)

    Wu, Chin-Han; Tseng, Ya-Shih; Yang, Chao-Chun; Kao, Yu-Ting; Sheu, Hamm-Ming; Liu, Hsiao-Sheng

    2013-11-01

    Arsenic may cause serious environmental pollution and is a serious industrial problem. Depending on the dosage, arsenic may trigger the cells undergoing either proliferation or apoptosis-related cell death. Because of lack of the proper animal model to study arsenic induced tumorigenesis, the accurate risk level of arsenic exposure has not been determined. Arsenic shows genotoxic effect on human beings who uptake water contaminated by arsenic. Chromosome aberration is frequently detected in arsenic exposure-related diseases and is associated with increased oxidative stress and decreased DNA repairing activity, but the underlying mechanism remains elusive. Aurora-A is a mitotic kinase, over-expression of Aurora-A leads to centrosome amplification, chromosomal instability and cell transformation. We revealed that Aurora-A is over-expressed in the skin and bladder cancer patients from blackfoot-disease endemic areas. Our cell line studies reveal that arsenic exposure between 0.5 μM and 1 μM for 2-7 days are able to induce Aurora-A expression and activation based on promoter activity, RNA and protein analysis. Aurora-A overexpression further increases the frequency of unsymmetrical chromosome segregation through centrosome amplification followed by cell population accumulated at S phase in immortalized keratinocyte (HaCaT) and uroepithelial cells (E7). Furthermore, Aurora-A over-expression was sustained for 1-4 weeks by chronic treatment of immortalized bladder and skin cells with NaAsO2. Aurora-A promoter methylation and gene amplification was not detected in the long-term arsenic treated E7 cells. Furthermore, the expression level of E2F1 transcription factor (E2F1) is increased in the presence of arsenic, and arsenic-related Aurora-A over-expression is transcriptionally regulated by E2F1. We further demonstrated that overexpression of Aurora-A and mutant Ha-ras or Aurora-A and mutant p53 may act additively to trigger arsenic-related bladder and skin cancer

  17. Suppression of colorectal tumorigenesis by recombinant Bacteroides fragilis enterotoxin-2 in vivo

    Science.gov (United States)

    Lv, You; Ye, Tao; Wang, Hui-Peng; Zhao, Jia-Ying; Chen, Wen-Jie; Wang, Xin; Shen, Chen-Xia; Wu, Yi-Bin; Cai, Yuan-Kun

    2017-01-01

    AIM To evaluate the impact of recombinant Bacteroides fragilis enterotoxin-2 (BFT-2, or Fragilysin) on colorectal tumorigenesis in mice induced by azoxymethane/dextran sulfate sodium (AOM/DSS). METHODS Recombinant proBFT-2 was expressed in Escherichia coli strain Rosetta (DE3) and BFT-2 was obtained and tested for its biological activity via colorectal adenocarcinoma cell strains SW-480. Seventy C57BL/6J mice were randomly divided into a blank (BC; n = 10), model (AD; n = 20), model + low-dose toxin (ADLT; n = 20, 10 μg), and a model + high-dose toxin (ADHT; n = 20, 20 μg) group. Mice weight, tumor formation and pathology were analyzed. Immunohistochemistry determined Ki-67 and Caspase-3 expression in normal and tumor tissues of colorectal mucosa. RESULTS Recombinant BFT-2 was successfully obtained, along with its biological activity. The most obvious weight loss occurred in the AD group compared with the ADLT group (21.82 ± 0.68 vs 23.23 ± 0.91, P < 0.05) and the ADHT group (21.82 ± 0.68 vs 23.57 ± 1.06, P < 0.05). More tumors were found in the AD group than in the ADLT and ADHT groups (19.75 ± 3.30 vs 6.50 ± 1.73, P < 0.05; 19.75 ± 3.30 vs 6.00 ± 2.16, P < 0.05). Pathology showed that 12 mice had adenocarcinoma and 6 cases had adenoma in the AD group. Five mice had adenocarcinoma and 15 had adenoma in the ADLT group. Four mice had adenocarcinoma and 16 had adenoma in the ADHT group. The incidence of colorectal adenocarcinoma in both the ADHT group and the ADHT group was reduced compared to that in the AD group (P < 0.05, P < 0.05). The positive rate of Ki-67 in the ADLT group and the ADHT group was 50% and 40%, respectively, both of which were lower than that found in the AD group (94.44%, P < 0.05, P < 0.05). Caspase-3 expression in the ADLT group and the ADHT group was 45% and 55%, both of which were higher than that found in the BC group (16.67%, P < 0.05, P < 0.05). CONCLUSION Oral administration with lower-dose biologically active recombinant BFT-2

  18. Exploring the gain of function contribution of AKT to mammary tumorigenesis in mouse models.

    Directory of Open Access Journals (Sweden)

    Carmen Blanco-Aparicio

    Full Text Available Elevated expression of AKT has been noted in a significant percentage of primary human breast cancers, mainly as a consequence of the PTEN/PI3K pathway deregulation. To investigate the mechanistic basis of the AKT gain of function-dependent mechanisms of breast tumorigenesis, we explored the phenotype induced by activated AKT transgenes in a quantitative manner. We generated several transgenic mice lines expressing different levels of constitutively active AKT in the mammary gland. We thoroughly analyzed the preneoplastic and neoplastic mammary lesions of these mice and correlated the process of tumorigenesis to AKT levels. Finally, we analyzed the impact that a possible senescent checkpoint might have in the tumor promotion inhibition observed, crossing these lines to mammary specific p53(R172H mutant expression, and to p27 knock-out mice. We analyzed the benign, premalignant and malignant lesions extensively by pathology and at molecular level analysing the expression of proteins involved in the PI3K/AKT pathway and in cellular senescence. Our findings revealed an increased preneoplastic phenotype depending upon AKT signaling which was not altered by p27 or p53 loss. However, p53 inactivation by R172H point mutation combined with myrAKT transgenic expression significantly increased the percentage and size of mammary carcinoma observed, but was not sufficient to promote full penetrance of the tumorigenic phenotype. Molecular analysis suggest that tumors from double myrAKT;p53(R172H mice result from acceleration of initiated p53(R172H tumors and not from bypass of AKT-induced oncogenic senescence. Our work suggests that tumors are not the consequence of the bypass of senescence in MIN. We also show that AKT-induced oncogenic senescence is dependent of pRb but not of p53. Finally, our work also suggests that the cooperation observed between mutant p53 and activated AKT is due to AKT-induced acceleration of mutant p53-induced tumors. Finally, our

  19. The functional and structural characterization of a novel oncogene GIG47 involved in the breast tumorigenesis

    Directory of Open Access Journals (Sweden)

    Han Kyou-Hoon

    2012-07-01

    Full Text Available Abstract Background A candidate oncogene GIG47, previously known as a neudesin with a neurotrophic activity, was identified by applying the differential expression analysis method. Methods As a first step to understand the molecular role of GIG47, we analyzed the expression profile of GIG47 in multiple human cancers including the breast cancer and characterized its function related to human carcinogenesis. Based on this oncogenic role of GIG47, we then embarked on determining the high-resolution structure of GIG47. We have applied multidimensional heteronuclear NMR methods to GIG47. Results GIG47 was over-expressed in primary breast tumors as well as other human tumors including carcinomas of the uterine cervix, malignant lymphoma, colon, lung, skin, and leukemia. To establish its role in the pathogenesis of breast cancer in humans, we generated stable transfectants of MCF7 cells. The ectopic expression of GIG47 in MCF7 cells promoted the invasiveness in the presence of 50% serum. In addition, it also resulted in the increased tumorigenicity in in vivo tumor formation assay. The tumorigenesis mechanism involving GIG47 might be mediated by the activation of MAPK and PI3K pathways. These results indicate that GIG47 plays a role in the breast tumorigenesis, thus representing a novel target for the treatment of breast cancer. To facilitate the development of GIG47-targeted therapeutics, we determined the structural configuration of GIG47. The high-resolution structure of GIG47 was obtained by combination of NMR and homology modeling. The overall structure of GIG47 has four α-helices and 6 β-strands, arranged in a β1-α1-β2-β3-α2-β4-α3-α4-β5-β6 topology. There is a potential heme/steroid binding pocket formed between two helices α2 and α3. Conclusion The determined three-dimensional structure of GIG47 may facilitate the development of potential anti-cancer agents.

  20. Overexpression of ligase defective E6-associated protein, E6-AP, results in mammary tumorigenesis.

    Science.gov (United States)

    Ramamoorthy, Sivapriya; Tufail, Rozina; Hokayem, Jimmy El; Jorda, Mercy; Zhao, Wei; Reis, Zizi; Nawaz, Zafar

    2012-02-01

    E6-associated protein (E6-AP) is a dual function protein. It acts as an E3 ubiquitin-protein ligase enzyme and coactivator of steroid hormone receptors such as estrogen (ERα) and progesterone (PR) receptors. It promotes the degradation of ERα and PR through the ubiquitin-proteasome pathway. Furthermore, it has been shown that the levels of E6-AP are inversely associated with that of ERα in human breast tumors. But the role of wild-type human E6-AP and its ubiquitin-protein ligase activity in mammary tumorigenesis is still unknown. To investigate this role, the authors utilized transgenic mice lines that specifically overexpress either the wild-type human E6-AP (E6-AP(WT)) or the ubiquitin-protein ligase defective E6-AP that contains C833S mutation (E6-AP(C833S)) in the mammary gland. To further substantiate the role of E6-AP in the development of breast tumorigenesis, it was also examined the expression of E6-AP in a large cohort of human breast cancer samples. The transgenic mice that overexpress wild-type E6-AP (E6-AP(WT)) fail to develop mammary tumors. Unlike the E6-AP(WT) mice, the E6-AP(C833S) mice that overexpress ubiquitin-protein ligase defective E6-AP protein develop mammary hyperplasia with a median latency of 18 months. These observations suggest that the inactivation of the ubiquitin-protein ligase function of E6-AP is sufficient to initiate the process of mammary tumor development. Furthermore, the data also suggests that E6-AP exerts its effects on target cells by modulating the protein levels and functions of ERα and PR. In addition, it was found in human breast cancer patients that the level of E6-AP is decreased in invasive breast tumors compared to normal breast tissue. Moreover, the authors also show that the survival patterns for E6-AP negative patients were worse compared to E6-AP positive patients. Taken together, these data suggests that E6-AP may act as a tumor suppressor in breast.

  1. Liver macrophages in healthy and diseased liver.

    Science.gov (United States)

    Abdullah, Zeinab; Knolle, Percy A

    2017-04-01

    Kupffer cells, the largest tissue resident macrophage population, are key for the maintenance of liver integrity and its restoration after injury and infections, as well as the local initiation and resolution of innate and adaptive immunity. These important roles of Kupffer cells were recently identified in healthy and diseased liver revealing diverse functions and phenotypes of hepatic macrophages. High-level phenotypic and genomic analysis revealed that Kupffer cells are not a homogenous population and that the hepatic microenvironment actively shapes both phenotype and function of liver macrophages. Compared to macrophages from other organs, hepatic macrophages bear unique properties that are instrumental for their diverse roles in local immunity as well as liver regeneration. The diverse and, in part, contradictory roles of hepatic macrophages in anti-tumor and inflammatory immune responses as well as regulatory and regenerative processes have been obscured by the lack of appropriate technologies to specifically target or ablate Kupffer cells or monocyte-derived hepatic macrophages. Future studies will need to dissect the exact role of the hepatic macrophages with distinct functional properties linked to their differentiation status and thereby provide insight into the functional plasticity of hepatic macrophages.

  2. Liver biopsy in liver patients with coagulopathy

    DEFF Research Database (Denmark)

    Ott, P.; Gronbaek, H.; Clausen, M.R.

    2008-01-01

    The risk of severe bleeding after liver biopsy is estimated to be 1:12,000 in patients with near normal coagulation (INR 60 billion /l). Beyond these limits, the risk is higher, but still uncertain. The Danish guidelines require INR > 1.5, platelet count

  3. Expression of Yes-associated protein modulates Survivin expression in primary liver malignancies.

    Science.gov (United States)

    Bai, Haibo; Gayyed, Mariana F; Lam-Himlin, Dora M; Klein, Alison P; Nayar, Suresh K; Xu, Yang; Khan, Mehtab; Argani, Pedram; Pan, Duojia; Anders, Robert A

    2012-09-01

    Hepatocellular carcinoma and intrahepatic cholangiocarcinoma account for 95% of primary liver cancer. For each of these malignancies, the outcome is dismal; incidence is rapidly increasing, and mechanistic understanding is limited. We observed abnormal proliferation of both biliary epithelium and hepatocytes in mice after genetic manipulation of Yes-associated protein, a transcription coactivator. Here, we comprehensively documented Yes-associated protein expression in the human liver and primary liver cancers. We showed that nuclear Yes-associated protein expression is significantly increased in human intrahepatic cholangiocarcinoma and hepatocellular carcinoma. We found that increased Yes-associated protein levels in hepatocellular carcinoma are due to multiple mechanisms including gene amplification and transcriptional and posttranscriptional regulation. Survivin, a member of the inhibitors-of-apoptosis protein family, has been reported as an independent prognostic factor for poor survival in both hepatocellular carcinoma and intrahepatic cholangiocarcinoma. We found that nuclear Yes-associated protein expression correlates significantly with nuclear Survivin expression for both intrahepatic cholangiocarcinoma and hepatocellular carcinoma. Furthermore, using mice engineered to conditionally overexpress Yes-associated protein in the liver, we found that Survivin messenger RNA expression depends upon Yes-associated protein levels. Our findings suggested that Yes-associated protein contributes to primary liver tumorigenesis and likely mediates its oncogenic effects through modulating Survivin expression.

  4. Activation of p21(CIP1/WAF1) in mammary epithelium accelerates mammary tumorigenesis and promotes lung metastasis.

    Science.gov (United States)

    Cheng, Xiaoyun; Xia, Weiya; Yang, Jer-Yen; Hsu, Jennifer L; Chou, Chao-Kai; Sun, Hui-Lung; Wyszomierski, Shannon L; Mills, Gordon B; Muller, William J; Yu, Dihua; Hung, Mien-Chie

    2010-12-03

    While p21 is well known to inhibit cyclin-CDK activity in the nucleus and it has also been demonstrated to have oncogenic properties in different types of human cancers. In vitro studies showed that the oncogenic function of p21is closely related to its cytoplasmic localization. However, it is unclear whether cytoplasmic p21 contributes to tumorigenesis in vivo. To address this question, we generated transgenic mice expressing the Akt-phosphorylated form of p21 (p21T145D) in the mammary epithelium. The results showed that Akt-activated p21 was expressed in the cytoplasm of mammary epithelium. Overexpression of Akt-activated p21 accelerated tumor onset and promoted lung metastasis in MMTV/neu mice, providing evidence that p21, especially cytoplasmic phosphorylated p21, has an oncogenic role in promoting mammary tumorigenesis and metastasis.

  5. Neudesin as a unique secreted protein with multi-functional roles in neural functions, energy metabolism, and tumorigenesis

    Directory of Open Access Journals (Sweden)

    Hiroya eOhta

    2015-05-01

    Full Text Available Neudesin was originally identified as a secreted protein with neurotrophic activity, and, thereafter, was also termed neuron-derived neurotrophic factor (NENF or the candidate oncogene GIG47. Neudesin with a conserved cytochrome 5-like heme/steroid-binding domain activates intracellular signaling pathways possibly through the activation of G protein-coupled receptors. In the brain, hypothalamic Neudesin decreases food intake. Neudesin knockout mice also exhibit anxiety-like behavior, indicating its roles in the hippocampal anxiety circuitry. Neudesin is also expressed in various peripheral tissues. Neudesin knockout mice are strongly resistant to high-fat diet-induced obesity due to elevated systemic sympathetic activity, heat production, and adipocytic lipolysis. Neudesin, which is over-expressed or induced by DNA hypomethylation in multiple human cancers, also stimulates tumorigenesis. These findings indicate that Neudesin plays roles in neural functions, energy metabolism, and tumorigenesis and is expected to be a novel target for obesity and anti-cancer treatments.

  6. NACK is an integral component of the Notch transcriptional activation complex and is critical for development and tumorigenesis.

    Science.gov (United States)

    Weaver, Kelly L; Alves-Guerra, Marie-Clotilde; Jin, Ke; Wang, Zhiqiang; Han, Xiaoqing; Ranganathan, Prathibha; Zhu, Xiaoxia; DaSilva, Thiago; Liu, Wei; Ratti, Francesca; Demarest, Renee M; Tzimas, Cristos; Rice, Meghan; Vasquez-Del Carpio, Rodrigo; Dahmane, Nadia; Robbins, David J; Capobianco, Anthony J

    2014-09-01

    The Notch signaling pathway governs many distinct cellular processes by regulating transcriptional programs. The transcriptional response initiated by Notch is highly cell context dependent, indicating that multiple factors influence Notch target gene selection and activity. However, the mechanism by which Notch drives target gene transcription is not well understood. Herein, we identify and characterize a novel Notch-interacting protein, Notch activation complex kinase (NACK), which acts as a Notch transcriptional coactivator. We show that NACK associates with the Notch transcriptional activation complex on DNA, mediates Notch transcriptional activity, and is required for Notch-mediated tumorigenesis. We demonstrate that Notch1 and NACK are coexpressed during mouse development and that homozygous loss of NACK is embryonic lethal. Finally, we show that NACK is also a Notch target gene, establishing a feed-forward loop. Thus, our data indicate that NACK is a key component of the Notch transcriptional complex and is an essential regulator of Notch-mediated tumorigenesis and development.

  7. Proteoglycans in liver cancer

    Science.gov (United States)

    Baghy, Kornélia; Tátrai, Péter; Regős, Eszter; Kovalszky, Ilona

    2016-01-01

    Proteoglycans are a group of molecules that contain at least one glycosaminoglycan chain, such as a heparan, dermatan, chondroitin, or keratan sulfate, covalently attached to the protein core. These molecules are categorized based on their structure, localization, and function, and can be found in the extracellular matrix, on the cell surface, and in the cytoplasm. Cell-surface heparan sulfate proteoglycans, such as syndecans, are the primary type present in healthy liver tissue. However, deterioration of the liver results in overproduction of other proteoglycan types. The purpose of this article is to provide a current summary of the most relevant data implicating proteoglycans in the development and progression of human and experimental liver cancer. A review of our work and other studies in the literature indicate that deterioration of liver function is accompanied by an increase in the amount of chondroitin sulfate proteoglycans. The alteration of proteoglycan composition interferes with the physiologic function of the liver on several levels. This article details and discusses the roles of syndecan-1, glypicans, agrin, perlecan, collagen XVIII/endostatin, endocan, serglycin, decorin, biglycan, asporin, fibromodulin, lumican, and versican in liver function. Specifically, glypicans, agrin, and versican play significant roles in the development of liver cancer. Conversely, the presence of decorin could potentially provide protective effects. PMID:26755884

  8. Cytokines and Liver Diseases

    Directory of Open Access Journals (Sweden)

    Herbert Tilg

    2001-01-01

    Full Text Available Cytokines are pleiotropic peptides produced by virtually every nucleated cell in the body. In most tissues, including the liver, constitutive production of cytokines is absent or minimal. There is increasing evidence that several cytokines mediate hepatic inflammation, apoptosis and necrosis of liver cells, cholestasis and fibrosis. Interestingly, the same mediators also mediate the regeneration of liver tissue after injury. Among the various cytokines, the proinflammatory cytokine tumour necrosis factor-alpha (TNF-a has emerged as a key factor in various aspects of liver disease, such as cachexia and/or cholestasis. Thus, antagonism of TNF-a and other injury-related cytokines in liver diseases merits evaluation as a treatment of these diseases. However, because the same cytokines are also necessary for the regeneration of the tissue after the liver has been injured, inhibition of these mediators might impair hepatic recovery. The near future will bring the exiting clinical challenge of testing new anticytokine strategies in various liver diseases.

  9. Proteoglycans in liver cancer.

    Science.gov (United States)

    Baghy, Kornélia; Tátrai, Péter; Regős, Eszter; Kovalszky, Ilona

    2016-01-07

    Proteoglycans are a group of molecules that contain at least one glycosaminoglycan chain, such as a heparan, dermatan, chondroitin, or keratan sulfate, covalently attached to the protein core. These molecules are categorized based on their structure, localization, and function, and can be found in the extracellular matrix, on the cell surface, and in the cytoplasm. Cell-surface heparan sulfate proteoglycans, such as syndecans, are the primary type present in healthy liver tissue. However, deterioration of the liver results in overproduction of other proteoglycan types. The purpose of this article is to provide a current summary of the most relevant data implicating proteoglycans in the development and progression of human and experimental liver cancer. A review of our work and other studies in the literature indicate that deterioration of liver function is accompanied by an increase in the amount of chondroitin sulfate proteoglycans. The alteration of proteoglycan composition interferes with the physiologic function of the liver on several levels. This article details and discusses the roles of syndecan-1, glypicans, agrin, perlecan, collagen XVIII/endostatin, endocan, serglycin, decorin, biglycan, asporin, fibromodulin, lumican, and versican in liver function. Specifically, glypicans, agrin, and versican play significant roles in the development of liver cancer. Conversely, the presence of decorin could potentially provide protective effects.

  10. Elastin in the Liver

    Directory of Open Access Journals (Sweden)

    Jiri Kanta

    2016-10-01

    Full Text Available A characteristic feature of liver cirrhosis is the accumulation of large amounts of connective tissue with the prevailing content of type I collagen. Elastin is a minor connective tissue component in normal liver but it is actively synthesized by hepatic stellate cells and portal fibroblasts in diseased liver. The accumulation of elastic fibers in later stages of liver fibrosis may contribute to the decreasing reversibility of the disease with advancing time. Elastin is formed by polymerization of tropoelastin monomers. It is an amorphous protein highly resistant to the action of proteases that forms the core of elastic fibers. Microfibrils surrounding the core are composed of fibrillins that bind a number of proteins involved in fiber formation. They include microfibril-associated glycoproteins (MAGPs, microfibrillar-associated proteins (MFAPs and fibulins. Lysyl oxidase (LOX and lysyl oxidase-like proteins (LOXLs are responsible for tropoelastin cross-linking and polymerization. TGF-β complexes attached to microfibrils release this cytokine and influence the behavior of the cells in the neighborhood. The role of TGF-β as the main profibrotic cytokine in the liver is well-known and the release of the cytokines of TGF-β superfamily from their storage in elastic fibers may affect the course of fibrosis. Elastic fibres are often studied in the tissues where they provide elasticity and resilience but their role is no longer viewed as purely mechanical. Tropoelastin, elastin polymer and elastin peptides resulting from partial elastin degradation influence fibroblastic and inflammatory cells as well as angiogenesis. A similar role may be performed by elastin in the liver. This article reviews the results of the research of liver elastic fibers on the backgound of the present knowledge of elastin biochemistry and physiology. The regulation of liver elastin synthesis and degradation may be important for the outcome of liver fibrosis.

  11. A zebrafish transgenic model of Ewing’s sarcoma reveals conserved mediators of EWS-FLI1 tumorigenesis

    Directory of Open Access Journals (Sweden)

    Stefanie W. Leacock

    2012-01-01

    Ewing’s sarcoma, a malignant bone tumor of children and young adults, is a member of the small-round-blue-cell tumor family. Ewing’s sarcoma family tumors (ESFTs, which include peripheral primitive neuroectodermal tumors (PNETs, are characterized by chromosomal translocations that generate fusions between the EWS gene and ETS-family transcription factors, most commonly FLI1. The EWS-FLI1 fusion oncoprotein represents an attractive therapeutic target for treatment of Ewing’s sarcoma. The cell of origin of ESFT and the molecular mechanisms by which EWS-FLI1 mediates tumorigenesis remain unknown, and few animal models of Ewing’s sarcoma exist. Here, we report the use of zebrafish as a vertebrate model of EWS-FLI1 function and tumorigenesis. Mosaic expression of the human EWS-FLI1 fusion protein in zebrafish caused the development of tumors with histology strongly resembling that of human Ewing’s sarcoma. The incidence of tumors increased in a p53 mutant background, suggesting that the p53 pathway suppresses EWS-FLI1-driven tumorigenesis. Gene expression profiling of the zebrafish tumors defined a set of genes that might be regulated by EWS-FLI1, including the zebrafish ortholog of a crucial EWS-FLI1 target gene in humans. Stable zebrafish transgenic lines expressing EWS-FLI1 under the control of the heat-shock promoter exhibit altered embryonic development and defective convergence and extension, suggesting that EWS-FLI1 interacts with conserved developmental pathways. These results indicate that functional targets of EWS-FLI1 that mediate tumorigenesis are conserved from zebrafish to human and provide a novel context in which to study the function of this fusion oncogene.

  12. Heparin-binding secretory transforming gene (hst) facilitates rat lactotrope cell tumorigenesis and induces prolactin gene transcription.

    OpenAIRE

    Shimon, I; Hüttner, A; Said, J; Spirina, O M; Melmed, S

    1996-01-01

    We have shown previously that human prolactinomas express transforming sequences of the heparin-binding secretory transforming gene (hst) which encodes fibroblast growth factor-4 (FGF-4). To elucidate the role of hst in pituitary tumorigenesis we treated primary rat pituitary and pituitary tumor cell cultures with recombinant FGF-4 and also stably transfected pituitary cell lines with full-length human hst cDNA. Transfectants were screened for hst mRNA expression and FGF-4 production. FGF-4 (...

  13. Prepubertal exposure to cow’s milk reduces susceptibility to carcinogen-induced mammary tumorigenesis in rats

    OpenAIRE

    Nielsen, Tina S.; Khan, Galam; Davis, Jennifer; Michels, Karin B; Hilakivi-Clarke, Leena

    2011-01-01

    Cow’s milk contains high levels of estrogens, progesterone and insulin-like growth factor 1 (IGF-1), all of which are associated with breast cancer. We investigated whether prepubertal milk exposure affects mammary gland development and carcinogenesis in rats. Sprague Dawley rats were given either whole milk or tap water to drink from postnatal day (PND) 14 to PND 35, and thereafter normal tap water. Mammary tumorigenesis was induced by administering 7,12-dimethylbenz[a]anthracene (DMBA) on P...

  14. Up-regulation of METCAM/MUC18 promotes motility, invasion, and tumorigenesis of human breast cancer cells

    Directory of Open Access Journals (Sweden)

    Cai Shao-xi

    2011-03-01

    Full Text Available Abstract Background Conflicting research has identified METCAM/MUC18, an integral membrane cell adhesion molecule (CAM in the Ig-like gene super-family, as both a tumor promoter and a tumor suppressor in the development of breast cancer. To resolve this, we have re-investigated the role of this CAM in the progression of human breast cancer cells. Methods Three breast cancer cell lines were used for the tests: one luminal-like breast cancer cell line, MCF7, which did not express any METCAM/MUC18, and two basal-like breast cancer cell lines, MDA-MB-231 and MDA-MB-468, which expressed moderate levels of the protein. MCF7 cells were transfected with the human METCAM/MUC18 cDNA to obtain G418-resistant clones which expressed the protein and were used for testing effects of human METCAM/MUC18 expression on in vitro motility and invasiveness, and in vitro and in vivo tumorigenesis. Both MDA-MB-231 and MDA-MB-468 cells already expressed METCAM/MUC18. They were directly used for in vitro tests in the presence and absence of an anti-METCAM/MUC18 antibody. Results In MCF7 cells, enforced METCAM/MUC18 expression increased in vitro motility, invasiveness, anchorage-independent colony formation (in vitro tumorigenesis, and in vivo tumorigenesis. In both MDA-MB-231 and MDA-MB-468 cells, the anti-METCAM/MUC18 antibody inhibited both motility and invasiveness. Though both MDA-MB-231 and MDA-MB-468 cells established a disorganized growth in 3D basement membrane culture assay, the introduction of the anti-METCAM/MUC18 antibody completely destroyed their growth in the 3D culture. Conclusion These findings support the notion that human METCAM/MUC18 expression promotes the progression of human breast cancer cells by increasing their motility, invasiveness and tumorigenesis.

  15. Kaposi sarcoma-associated herpesvirus promotes tumorigenesis by modulating the Hippo pathway.

    Science.gov (United States)

    Liu, G; Yu, F-X; Kim, Y C; Meng, Z; Naipauer, J; Looney, D J; Liu, X; Gutkind, J S; Mesri, E A; Guan, K-L

    2015-07-01

    Kaposi sarcoma-associated herpesvirus (KSHV) is an oncogenic virus and the culprit behind the human disease Kaposi sarcoma (KS), an AIDS-defining malignancy. KSHV encodes a viral G-protein-coupled receptor (vGPCR) critical for the initiation and progression of KS. In this study, we identified that YAP/TAZ, two homologous oncoproteins inhibited by the Hippo tumor suppressor pathway, are activated in KSHV-infected cells in vitro, KS-like mouse tumors and clinical human KS specimens. The KSHV-encoded vGPCR acts through Gq/11 and G12/13 to inhibit the Hippo pathway kinases Lats1/2, promoting the activation of YAP/TAZ. Furthermore, depletion of YAP/TAZ blocks vGPCR-induced cell proliferation and tumorigenesis in a xenograft mouse model. The vGPCR-transformed cells are sensitive to pharmacologic inhibition of YAP. Our study establishes a pivotal role of the Hippo pathway in mediating the oncogenic activity of KSHV and development of KS, and also suggests a potential of using YAP inhibitors for KS intervention.

  16. A circular RNA promotes tumorigenesis by inducing c-myc nuclear translocation.

    Science.gov (United States)

    Yang, Qi; Du, William W; Wu, Nan; Yang, Weining; Awan, Faryal Mehwish; Fang, Ling; Ma, Jian; Li, Xiangmin; Zeng, Yan; Yang, Zhenguo; Dong, Jun; Khorshidi, Azam; Yang, Burton B

    2017-09-01

    Circular RNAs (circRNAs) are a subclass of noncoding RNAs widely expressed in mammalian cells. We report here the tumorigenic capacity of a circRNA derived from angiomotin-like1 (circ-Amotl1). Circ-Amotl1 is highly expressed in patient tumor samples and cancer cell lines. Single-cell inoculations using circ-Amotl1-transfected tumor cells showed a 30-fold increase in proliferative capacity relative to control. Agarose colony-formation assays similarly revealed a 142-fold increase. Tumor-take rate in nude mouse xenografts using 6-day (219 cells) and 3-day (9 cells) colonies were 100%, suggesting tumor-forming potential of every cell. Subcutaneous single-cell injections led to the formation of palpable tumors in 41% of mice, with tumor sizes >1 cm(3) in 1 month. We further found that this potent tumorigenicity was triggered through interactions between circ-Amotl1 and c-myc. A putative binding site was identified in silico and tested experimentally. Ectopic expression of circ-Amotl1 increased retention of nuclear c-myc, appearing to promote c-myc stability and upregulate c-myc targets. Expression of circ-Amotl1 also increased the affinity of c-myc binding to a number of promoters. Our study therefore reveals a novel function of circRNAs in tumorigenesis, and this subclass of noncoding RNAs may represent a potential target in cancer therapy.

  17. JNK2 downregulation promotes tumorigenesis and chemoresistance by decreasing p53 stability in bladder cancer

    Science.gov (United States)

    Zhao, Yu; Qian, Chenchen; Wang, Liguo; Qi, Jun

    2016-01-01

    Bladder cancer is one of the most common malignancies of the urinary system, and the 5-year survival rate remains low. A comprehensive understanding of the carcinogenesis and progression of bladder cancer is urgently needed to advance treatment. c-Jun N-terminal kinase-2 (JNK2) exhibits both tumor promoter and tumor suppressor actions, depending on tumor type. Here, we analyzed the JNK2 function in bladder cancer. Using gene expression microarrays, we demonstrated that JNK2 mRNA is downregulated in an orthotopic rat model of bladder cancer. JNK2 protein levels were lower in rat and human bladder cancer tissues than in normal tissues, and the levels correlated with those of p53. Moreover, JNK2 phosphorylated p53 at Thr-81, thus protecting p53 from MDM2-induced proteasome degradation. Decreased expression of JNK2 in T24 cells conferred resistance to cell death induced by mitomycin C. Furthermore, lower JNK2 expression was associated with poorer overall survival among patients who underwent radical cystectomy. These results indicate that JNK2 acts as a tumor suppressor in bladder cancer, and that decreased JNK2 expression promotes bladder cancer tumorigenesis. PMID:27147566

  18. RNAi technology and lentiviral delivery as a powerful tool to suppress Tpr-Met-mediated tumorigenesis.

    Science.gov (United States)

    Taulli, Riccardo; Accornero, Paolo; Follenzi, Antonia; Mangano, Tony; Morotti, Alessandro; Scuoppo, Claudio; Forni, Paolo E; Bersani, Francesca; Crepaldi, Tiziana; Chiarle, Roberto; Naldini, Luigi; Ponzetto, Carola

    2005-05-01

    Tpr-Met, the oncogenic counterpart of the Met receptor, has been detected in gastric cancers, as well as in precursor lesions and in the adjacent normal gastric mucosa. This has prompted the suggestion that Tpr-Met may predispose to the development of gastric tumors. Given the sequence specificity of RNA interference, oncogenes activated by point mutation or rearrangements can be targeted while spearing the product of the wild-type allele. In this work, we report specific suppression of Tpr-Met expression and inhibition of Tpr-Met-mediated transformation and tumorigenesis by means of a short interfering RNA (siRNA) directed toward the Tpr-Met junction (anti-TM2). When delivered by a lentiviral vector, anti-TM2 siRNA was effective also in mouse embryonal fibroblasts or epithelial cells expressing high levels of Tpr-Met. Our results suggest that lentiviral-mediated delivery of anti-TM2 siRNA may be developed into a powerful tool to treat Tpr-Met-positive cancers.

  19. Nisin ZP, a Bacteriocin and Food Preservative, Inhibits Head and Neck Cancer Tumorigenesis and Prolongs Survival.

    Science.gov (United States)

    Kamarajan, Pachiyappan; Hayami, Takayuki; Matte, Bibiana; Liu, Yang; Danciu, Theodora; Ramamoorthy, Ayyalusamy; Worden, Francis; Kapila, Sunil; Kapila, Yvonne

    2015-01-01

    The use of small antimicrobial peptides or bacteriocins, like nisin, to treat cancer is a new approach that holds great promise. Nisin exemplifies this new approach because it has been used safely in humans for many years as a food preservative, and recent laboratory studies support its anti-tumor potential in head and neck cancer. Previously, we showed that nisin (2.5%, low content) has antitumor potential in head and neck squamous cell carcinoma (HNSCC) in vitro and in vivo. The current studies explored a naturally occurring variant of nisin (nisin ZP; 95%, high content) for its antitumor effects in vitro and in vivo. Nisin ZP induced the greatest level of apoptosis in HNSCC cells compared to low content nisin. HNSCC cells treated with increasing concentrations of nisin ZP exhibited increasing levels of apoptosis and decreasing levels of cell proliferation, clonogenic capacity, and sphere formation. Nisin ZP induced apoptosis through a calpain-dependent pathway in HNSCC cells but not in human oral keratinocytes. Nisin ZP also induced apoptosis dose-dependently in human umbilical vein endothelial cells (HUVEC) with concomitant decreases in vascular sprout formation in vitro and reduced intratumoral microvessel density in vivo. Nisin ZP reduced tumorigenesis in vivo and long-term treatment with nisin ZP extended survival. In addition, nisin treated mice exhibited normal organ histology with no evidence of inflammation, fibrosis or necrosis. In summary, nisin ZP exhibits greater antitumor effects than low content nisin, and thus has the potential to serve as a novel therapeutic for HNSCC.

  20. Epigenetic loss of the PIWI/piRNA machinery in human testicular tumorigenesis.

    Science.gov (United States)

    Ferreira, Humberto J; Heyn, Holger; Garcia del Muro, Xavier; Vidal, August; Larriba, Sara; Muñoz, Clara; Villanueva, Alberto; Esteller, Manel

    2014-01-01

    Although most cancer research has focused in mRNA, non-coding RNAs are also an essential player in tumorigenesis. In addition to the well-recognized microRNAs, recent studies have also shown that epigenetic silencing by CpG island hypermethylation of other classes of non-coding RNAs, such as transcribed ultraconserved regions (T-UCRs) or small nucleolar RNAs (snoRNAs), also occur in human neoplasia. Herein we have studied the putative existence of epigenetic aberrations in the activity of PIWI proteins, an Argonaute family protein subclass, and the small regulatory PIWI-interacting RNAs (piRNAs) in testicular cancer, as the PIWI/piRNA pathway plays a critical role in male germline development. We have observed the existence of promoter CpG island hypermethylation-associated silencing of PIWIL1, PIWIL2, PIWIL4, and TDRD1 in primary seminoma and non-seminoma testicular tumors, in addition to testicular germ cell tumor cell lines. Most importantly, these epigenetic lesions occur in a context of piRNA downregulation and loss of DNA methylation of the LINE-1 repetitive sequences, one of the target genomic loci where the PIWI/piRNA machinery acts as a caretaker in non-transformed cells.

  1. Astrocyte Elevated Gene-1 Mediates Glycolysis and Tumorigenesis in Colorectal Carcinoma Cells via AMPK Signaling

    Directory of Open Access Journals (Sweden)

    Hong-tao Song

    2014-01-01

    Full Text Available To investigate the role of AEG-1 in glycolysis and tumorigenesis, we construct myc-AEG-1 expression vector and demonstrate a novel mechanism that AEG-1 may increase the activity of AMPK by Thr172 phosphorylation. The higher expression levels of AEG-1 in colorectal carcinoma cells were found but showed significant difference in different cell lines. To study the role of AEG-1 in colorectal cells, myc-AEG-1 vector was constructed and transfected into NCM460 colonic epithelial cells. We observed consistent increasing of glucose consumption and lactate production, typical features of anaerobic glycolysis, suggesting that AEG-1 may promote anaerobic glycolysis. Moreover, we noted that AMPK phosphorylation at Thr172 as well as pPFK2 (Ser466 was increased in NCM460 cells overexpressing AEG-1. Compound C may block AMPK and PFK2 phosphorylation in both control and AEG-1-overexpressed cells and decrease the glucose consumption and lactate production. The present findings indicated that reduced AEG-1 protein levels by RNAi may decrease the glucose consumption and lactate production in HCT116 colorectal carcinoma cells. The present identified AEG-1/AMPK/PFK2 glycolysis cascade may be essential to cell proliferation and tumor growth. The present results may provide us with a mechanistic insight into novel targets controlled by AEG-1, and the components in the AEG-1/AMPK/PFK2 glycolysis process may be targeted for the clinical treatment of cancer.

  2. Long-chain fatty acid analogues suppress breast tumorigenesis and progression.

    Science.gov (United States)

    Gluschnaider, Udi; Hertz, Rachel; Ohayon, Sarit; Smeir, Elia; Smets, Martha; Pikarsky, Eli; Bar-Tana, Jacob

    2014-12-01

    Obesity and type 2 diabetes (T2D) are associated with increased breast cancer incidence and mortality, whereas carbohydrate-restricted ketogenic diets ameliorate T2D and suppress breast cancer. These observations suggest an inherent efficacy of nonesterified long-chain fatty acids (LCFA) in suppressing T2D and breast tumorigenesis. In this study, we investigated novel antidiabetic MEDICA analogues consisting of methyl-substituted LCFA that are neither β-oxidized nor esterified to generate lipids, prompting interest in their potential efficacy as antitumor agents in the context of breast cancer. In the MMTV-PyMT oncomouse model of breast cancer, in which we confirmed that tumor growth could be suppressed by a carbohydrate-restricted ketogenic diet, MEDICA treatment suppressed tumor growth, and lung metastasis, promoting a differentiated phenotype while suppressing mesenchymal markers. In human breast cancer cells, MEDICA treatment attenuated signaling through the STAT3 and c-Src transduction pathways. Mechanistic investigations suggested that MEDICA suppressed c-Src-transforming activity by elevating reactive oxygen species production, resulting in c-Src oxidation and oligomerization. Our findings suggest that MEDICA analogues may offer therapeutic potential in breast cancer and overcome the poor compliance of patients to dietary carbohydrate restriction.

  3. Recurrent MLK4 Loss-of-Function Mutations Suppress JNK Signaling to Promote Colon Tumorigenesis

    Science.gov (United States)

    Marusiak, Anna A.; Stephenson, Natalie L.; Baik, Hayeon; Trotter, Eleanor W.; Li, Yaoyong; Blyth, Karen; Mason, Susan; Chapman, Phil; Puto, Lorena A.; Read, Jon A.; Brassington, Claire; Pollard, Hannah K.; Phillips, Chris; Green, Isabelle; Overman, Ross; Collier, Matthew; Testoni, Ewelina; Miller, Crispin J.; Hunter, Tony; Sansom, Owen J.; Brognard, John

    2015-01-01

    MLK4 is a member of the mixed-lineage family of kinases that regulate the JNK, p38, and ERK kinase signaling pathways. MLK4 mutations have been identified in various human cancers including frequently in colorectal cancer, where their function and pathobiological importance has been uncertain. In this study, we assessed the functional consequences of MLK4 mutations in colon tumorigenesis. Biochemical data indicated that a majority of MLK4 mutations are loss-of-function (LOF) mutations that can exert dominant negative effects. In seeking to understand the abrogated activity of these mutants, we elucidated a new MLK4 catalytic domain structure. To determine whether MLK4 is required to maintain the tumorigenic phenotype, we reconstituted its signaling axis in colon cancer cells harboring MLK4 inactivating mutations. We found that restoring MLK4 activity reduced cell viability, proliferation, and colony formation in vitro and delayed tumor growth in vivo. Mechanistic investigations established that restoring the function of MLK4 selectively induced the JNK pathway and its downstream targets, cJUN, ATF3 and the cyclin-dependent kinase inhibitors CDKN1A and CDKN2B. Our work indicates that MLK4 is a novel tumor suppressing kinase harboring frequent LOF mutations that lead to diminished signaling in the JNK pathway and enhanced proliferation in colon cancer. PMID:26637668

  4. Cancer-associated splicing variant of tumor suppressor AIMP2/p38: pathological implication in tumorigenesis.

    Directory of Open Access Journals (Sweden)

    Jin Woo Choi

    2011-03-01

    Full Text Available Although ARS-interacting multifunctional protein 2 (AIMP2, also named as MSC p38 was first found as a component for a macromolecular tRNA synthetase complex, it was recently discovered to dissociate from the complex and work as a potent tumor suppressor. Upon DNA damage, AIMP2 promotes apoptosis through the protective interaction with p53. However, it was not demonstrated whether AIMP2 was indeed pathologically linked to human cancer. In this work, we found that a splicing variant of AIMP2 lacking exon 2 (AIMP2-DX2 is highly expressed by alternative splicing in human lung cancer cells and patient's tissues. AIMP2-DX2 compromised pro-apoptotic activity of normal AIMP2 through the competitive binding to p53. The cells with higher level of AIMP2-DX2 showed higher propensity to form anchorage-independent colonies and increased resistance to cell death. Mice constitutively expressing this variant showed increased susceptibility to carcinogen-induced lung tumorigenesis. The expression ratio of AIMP2-DX2 to normal AIMP2 was increased according to lung cancer stage and showed a positive correlation with the survival of patients. Thus, this work identified an oncogenic splicing variant of a tumor suppressor, AIMP2/p38, and suggests its potential for anti-cancer target.

  5. Oligonucleotide microarray identifies genes differentially expressed during tumorigenesis of DMBA-induced pancreatic cancer in rats.

    Directory of Open Access Journals (Sweden)

    Jun-Chao Guo

    Full Text Available The extremely dismal prognosis of pancreatic cancer (PC is attributed, at least in part, to lack of early diagnosis. Therefore, identifying differentially expressed genes in multiple steps of tumorigenesis of PC is of great interest. In the present study, a 7,12-dimethylbenzanthraene (DMBA-induced PC model was established in male Sprague-Dawley rats. The gene expression profile was screened using an oligonucleotide microarray, followed by real-time quantitative polymerase chain reaction (qRT-PCR and immunohistochemical staining validation. A total of 661 differentially expressed genes were identified in stages of pancreatic carcinogenesis. According to GO classification, these genes were involved in multiple molecular pathways. Using two-way hierarchical clustering analysis, normal pancreas, acute and chronic pancreatitis, PanIN, early and advanced pancreatic cancer were completely discriminated. Furthermore, 11 upregulated and 142 downregulated genes (probes were found by Mann-Kendall trend Monotone test, indicating homologous genes of rat and human. The qRT-PCR and immunohistochemistry analysis of CXCR7 and UBe2c, two of the identified genes, confirmed the microarray results. In human PC cell lines, knockdown of CXCR7 resulted in decreased migration and invasion. Collectively, our data identified several promising markers and therapeutic targets of PC based on a comprehensive screening and systemic validation.

  6. Knockdown of DDX46 Inhibits the Invasion and Tumorigenesis in Osteosarcoma Cells.

    Science.gov (United States)

    Jiang, Feng; Zhang, Dengfeng; Li, Guojun; Wang, Xiao

    2017-03-13

    DDX46, a member of the DEAD-box (DDX) helicase family, is involved in the development of several tumors. However, the exact role of DDX46 in osteosarcoma and the underlying mechanisms in tumorigenesis remain poorly understood. Thus, in the present study, we explored the role of DDX46 in osteosarcoma and the underlying mechanisms. Our results demonstrated that the expression levels of DDX46 in both mRNA and protein were greatly elevated in human osteosarcoma tissues and cell lines. Knockdown of DDX46 obviously inhibited osteosarcoma cell proliferation and tumor growth in vivo. In addition, knockdown of DDX46 also significantly suppressed migration and invasion in osteosarcoma cells. Furthermore, knockdown of DDX46 substantially downregulated the phosphorylation levels of PI3K and Akt in SaOS2 cells. In summary, the present results have revealed that DDX46 plays an important role in osteosarcoma growth and metastasis. Knockdown of DDX46 inhibited osteosarcoma cell proliferation, migration, and invasion in vitro and tumor growth in vivo. Therefore, DDX46 may be a potential therapeutic target for the treatment of osteosarcoma.

  7. A potential role for Helicobacter pylori heat shock protein 60 in gastric tumorigenesis

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Chen-Si [Department of Biological Science and Technology, National Chiao-Tung University, Hsin-Chu, Taiwan (China); School of Veterinary Medicine, National Taiwan University, Taipei, Taiwan (China); He, Pei-Juin [Department of Biological Science and Technology, National Chiao-Tung University, Hsin-Chu, Taiwan (China); Tsai, Nu-Man [School of Medical Laboratory and Biotechnology, Chung Shan Medical University, Taichung, Taiwan (China); Li, Chi-Han; Yang, Shang-Chih; Hsu, Wei-Tung [Department of Biological Science and Technology, National Chiao-Tung University, Hsin-Chu, Taiwan (China); Wu, Ming-Shiang [Department of Internal Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan (China); Wu, Chang-Jer [Department of Food Science, National Taiwan Ocean University, Keelung, Taiwan (China); Cheng, Tain-Lu [Department of Biotechnology, Kaohsiung Medical University, Kaohsiung, Taiwan (China); Liao, Kuang-Wen, E-mail: kitchhen@yahoo.com.tw [Department of Biological Science and Technology, National Chiao-Tung University, Hsin-Chu, Taiwan (China)

    2010-02-05

    Helicobacter pylori has been found to promote the malignant process leading to gastric cancer. Heat shock protein 60 of H. pylori (HpHSP60) was previously been identified as a potent immunogene. This study investigates the role of HpHSP60 in gastric cancer carcinogenesis. The effect of HpHSP60 on cell proliferation, anti-death activity, angiogenesis and cell migration were explored. The results showed that HpHSP60 enhanced migration by gastric cancer cells and promoted tube formation by umbilical vein endothelial cells (HUVECs); however, HpHSP60 did not increase cell proliferation nor was this protein able to rescue gastric cancer cells from death. Moreover, the results also indicated HpHSP60 had different effects on AGS gastric cancer cells or THP-1 monocytic cells in terms of their expression of pro-inflammatory cytokines, which are known to be important to cancer development. We propose that HpHSP60 may trigger the initiation of carcinogenesis by inducing pro-inflammatory cytokine release and by promoting angiogenesis and metastasis. Thus, this extracellular pathogen-derived HSP60 is potentially a vigorous virulence factor that can act as a carcinogen during gastric tumorigenesis.

  8. Extraintestinal Helminth Infection Reduces the Development of Colitis-Associated Tumorigenesis

    Science.gov (United States)

    León-Cabrera, Sonia; Callejas, Blanca E.; Ledesma-Soto, Yadira; Coronel, Jossimar; Pérez-Plasencia, Carlos; Gutiérrez-Cirlos, Emma B.; Ávila-Moreno, Federico; Rodríguez-Sosa, Miriam; Hernández-Pando, Rogelio; Marquina-Castillo, Brenda; Chirino, Yolanda I.; Terrazas, Luis I.

    2014-01-01

    Colitis-associated colorectal cancer (CAC) is one of the most common cancers and is closely related to chronic or deregulated inflammation. Helminthic infections can modulate inflammatory responses in some diseases, but their immunomodulatory role during cancer development remains completely unknown. We have analyzed the role of Taenia crassiceps-induced anti-inflammatory response in determining the outcome of CAC. We show that extraintestinal T. crassiceps infection in CAC mice inhibited colonic inflammatory responses and tumor formation and prevented goblet cell loss. There was also increased expression of IL-4 and alternatively activated macrophages markers in colonic tissue and negative immunomodulation of pro-inflammatory cytokine expression. In addition, T. crassiceps infection prevented the upregulation of β-catenin and CXCR2 expression observed in the CAC mice, which are both markers associated with CAC-tumorigenesis, and reduced the numbers of circulating and colonic CD11b+Ly6ChiCCR2+ monocytes. Thus, immunomodulatory activities induced by helminth infections may have a role in the progression of CAC. PMID:25210492

  9. Targeting tumorigenesis: development and use of mTOR inhibitors in cancer therapy

    Directory of Open Access Journals (Sweden)

    Kay Andrea

    2009-10-01

    Full Text Available Abstract The mammalian target of rapamycin (mTOR is an intracellular serine/threonine protein kinase positioned at a central point in a variety of cellular signaling cascades. The established involvement of mTOR activity in the cellular processes that contribute to the development and progression of cancer has identified mTOR as a major link in tumorigenesis. Consequently, inhibitors of mTOR, including temsirolimus, everolimus, and ridaforolimus (formerly deforolimus have been developed and assessed for their safety and efficacy in patients with cancer. Temsirolimus is an intravenously administered agent approved by the US Food and Drug Administration (FDA and the European Medicines Agency (EMEA for the treatment of advanced renal cell carcinoma (RCC. Everolimus is an oral agent that has recently obtained US FDA and EMEA approval for the treatment of advanced RCC after failure of treatment with sunitinib or sorafenib. Ridaforolimus is not yet approved for any indication. The use of mTOR inhibitors, either alone or in combination with other anticancer agents, has the potential to provide anticancer activity in numerous tumor types. Cancer types in which these agents are under evaluation include neuroendocrine tumors, breast cancer, leukemia, lymphoma, hepatocellular carcinoma, gastric cancer, pancreatic cancer, sarcoma, endometrial cancer, and non-small-cell lung cancer. The results of ongoing clinical trials with mTOR inhibitors, as single agents and in combination regimens, will better define their activity in cancer.

  10. Multiple functions of DDX3 RNA helicase in gene regulation, tumorigenesis and viral infection

    Directory of Open Access Journals (Sweden)

    YASUO eARIUMI

    2014-12-01

    Full Text Available The DEAD-box RNA helicase DDX3 is a multifunctional protein involved in all aspects of RNA metabolism, including transcription, splicing, mRNA nuclear export, translation, RNA decay and ribosome biogenesis. In addition, DDX3 is also implicated in cell cycle regulation, apoptosis, Wnt-ß-catenin signaling, tumorigenesis, and viral infection. Notably, recent studies suggest that DDX3 is a component of anti-viral innate immune signaling pathways. Indeed, DDX3 contributes to enhance the induction of anti-viral mediators, interferon regulatory factor (IRF 3 and type I interferon (IFN. However, DDX3 seems to be an important target for several viruses, such as human immunodeficiency virus (HIV-1, hepatitis C virus (HCV, hepatitis B virus (HBV, and poxvirus. DDX3 interacts with HIV-1 Rev or HCV Core protein and modulates its function. At least, DDX3 is required for both HIV-1 and HCV replication. Therefore, DDX3 could be a novel therapeutic target for the development of drug against HIV-1 and HCV.

  11. Multiple functions of DDX3 RNA helicase in gene regulation, tumorigenesis, and viral infection.

    Science.gov (United States)

    Ariumi, Yasuo

    2014-01-01

    The DEAD-box RNA helicase DDX3 is a multifunctional protein involved in all aspects of RNA metabolism, including transcription, splicing, mRNA nuclear export, translation, RNA decay and ribosome biogenesis. In addition, DDX3 is also implicated in cell cycle regulation, apoptosis, Wnt-β-catenin signaling, tumorigenesis, and viral infection. Notably, recent studies suggest that DDX3 is a component of anti-viral innate immune signaling pathways. Indeed, DDX3 contributes to enhance the induction of anti-viral mediators, interferon (IFN) regulatory factor 3 and type I IFN. However, DDX3 seems to be an important target for several viruses, such as human immunodeficiency virus type 1 (HIV-1), hepatitis C virus (HCV), hepatitis B virus (HBV), and poxvirus. DDX3 interacts with HIV-1 Rev or HCV Core protein and modulates its function. At least, DDX3 is required for both HIV-1 and HCV replication. Therefore, DDX3 could be a novel therapeutic target for the development of drug against HIV-1 and HCV.

  12. Detection of tumorigenesis in urinary bladder with optical coherence tomography: optical characterization of morphological changes

    Science.gov (United States)

    Xie, T.-Q.; Zeidel, M. L.; Pan, Yingtian

    2002-12-01

    Most transitional cell tumorigenesis involves three stages of subcellular morphological changes: hyperplasia, dysplasia and neoplasia. Previous studies demonstrated that owing to its high spatial resolution and intermediate penetration depth, current OCT technology including endoscopic OCT could delineate the urothelium, submucosa and the upper muscular layers of the bladder wall. In this paper, we will discuss the sensitivity and limitations of OCT in diagnosing and staging bladder cancer. Based on histomorphometric evaluations of nuclear morphology, we modeled the resultant backscattering changes and the characteristic changes in OCT image contrast. In the theoretical modeling, we assumed that nuclei were the primary sources of scattering and were uniformly distributed in the uroepithelium, and compared with the results of the corresponding prior OCT measurements. According to our theoretical modeling, normal bladder shows a thin, uniform and low scattering urothelium, so does an inflammatory lesion except thickening in the submucosa. Compared with a normal bladder, a hyperplastic lesion exhibits a thickened, low scattering urothelium whereas a neoplastic lesion shows a thickened urothelium with increased backscattering. These results support our previous animal study that OCT has the potential to differentiate inflammation, hyperplasia, and neoplasia by quantifying the changes in urothelial thickening and backscattering. The results also suggest that OCT might not have the sensitivity to differentiate the subtle morphological changes between hyperplasia and dysplasia based on minor backscattering differences.

  13. Human papillomavirus E6 and E7 oncoproteins as risk factors for tumorigenesis

    Indian Academy of Sciences (India)

    Niladri Ganguly; Suraj P Parihar

    2009-03-01

    Human papillomavirus (HPV) is small, double-stranded DNA virus that infects mucosal and cutaneous epithelial tissue. HPV is sexually transmitted and the viral DNA replicates extrachromosomally. The virus is non-enveloped and has an icosahedral capsid. There are approximately 118 types of HPV, which are characterized as high-risk or low-risk types. High-risk HPVs cause malignant transformation while the low-risk ones cause benign warts and lesions. The expression of E6 and E7 is normally controlled during the normal viral life cycle when viral DNA replicates extrachromosomally. HPV E6 and E7 oncoproteins are overexpressed when the viral genome integrates into the host DNA. Deregulated overexpression of E6 and E7 oncoproteins can cause several changes in cellular pathways and functions leading to malignant transformation of cells and tumorigenesis. In this review, we focus on several cellular mechanisms and pathways that are altered in the presence of E6 and E7, the target proteins of E6 and E7 inside the host cell and how they contribute to the development of the transformed phenotype..

  14. Influence of dietary menhaden oil on 7,12-dimethylbenzanthracene induced mammary tumorigenesis in rats

    Energy Technology Data Exchange (ETDEWEB)

    O' Connor, T.P.; Peterson, F.; Campbell, T.C.

    1986-03-05

    The effect of dietary menhaden oil on 7,12-dimethylbenzanthracene (DMBA) induced mammary tumorigenesis was examined in female Sprague-Dawley rats. Rats were obtained at age 28 days and acclimated until age 50 days when they received a single i.g. dose of 5 mg DMBA dissolved in 1 ml corn oil. Rats were then randomly assigned to one of four treatment groups with 25 rats per group. One group was fed a diet based on fish protein (freeze-dried cod) and corn oil (F/C). The second group received a diet based on fish protein and menhaden oil (F/M). The third group received a casein based diet with corn oil as the lipid source (C/C). The fourth group was fed a casein based diet with menhaden oil as the lipid source (C/M). Both the protein and lipid sources were fed at a level of 20% by weight of the diets. Rats were palpated weekly to check for mammary tumor development and the experiment was terminated 24 weeks after DMBA administration. Rats fed menhaden oil as a lipid source (F/M and C/M groups) developed significantly fewer mammary tumors than animals on the corn oil based diets (F/C and C/C groups, respectively). Thus, menhaden oil, rich in omega-3 fatty acids, significantly inhibited the development of DMBA induced mammary tumors in this experiment.

  15. Intestinal tumorigenesis is not affected by progesterone signaling in rodent models.

    Directory of Open Access Journals (Sweden)

    Jarom Heijmans

    Full Text Available Clinical data suggest that progestins have chemopreventive properties in the development of colorectal cancer. We set out to examine a potential protective effect of progestins and progesterone signaling on colon cancer development. In normal and neoplastic intestinal tissue, we found that the progesterone receptor (PR is not expressed. Expression was confined to sporadic mesenchymal cells. To analyze the influence of systemic progesterone receptor signaling, we crossed mice that lacked the progesterone receptor (PRKO to the Apc(Min/+ mouse, a model for spontaneous intestinal polyposis. PRKO-Apc(Min/+ mice exhibited no change in polyp number, size or localization compared to Apc(Min/+. To examine effects of progestins on the intestinal epithelium that are independent of the PR, we treated mice with MPA. We found no effects of either progesterone or MPA on gross intestinal morphology or epithelial proliferation. Also, in rats treated with MPA, injection with the carcinogen azoxymethane did not result in a difference in the number or size of aberrant crypt foci, a surrogate end-point for adenoma development. We conclude that expression of the progesterone receptor is limited to cells in the intestinal mesenchyme. We did not observe any effect of progesterone receptor signaling or of progestin treatment in rodent models of intestinal tumorigenesis.

  16. β-catenin functions pleiotropically in differentiation and tumorigenesis in mouse embryo-derived stem cells.

    Directory of Open Access Journals (Sweden)

    Noriko Okumura

    Full Text Available The canonical Wnt/β-catenin signaling pathway plays a crucial role in the maintenance of the balance between proliferation and differentiation throughout embryogenesis and tissue homeostasis. β-Catenin, encoded by the Ctnnb1 gene, mediates an intracellular signaling cascade activated by Wnt. It also plays an important role in the maintenance of various types of stem cells including adult stem cells and cancer stem cells. However, it is unclear if β-catenin is required for the derivation of mouse embryo-derived stem cells. Here, we established β-catenin-deficient (β-cat(Δ/Δ mouse embryo-derived stem cells and showed that β-catenin is not essential for acquiring self-renewal potential in the derivation of mouse embryonic stem cells (ESCs. However, teratomas formed from embryo-derived β-cat(Δ/Δ ESCs were immature germ cell tumors without multilineage differentiated cell types. Re-expression of functional β-catenin eliminated their neoplastic, transformed phenotype and restored pluripotency, thereby rescuing the mutant ESCs. Our findings demonstrate that β-catenin has pleiotropic effects in ESCs; it is required for the differentiation of ESCs and prevents them from acquiring tumorigenic character. These results highlight β-catenin as the gatekeeper in differentiation and tumorigenesis in ESCs.

  17. EMP-1 promotes tumorigenesis of NSCLC through PI3K/AKT pathway.

    Science.gov (United States)

    Lai, Senyan; Wang, Guihua; Cao, Xiaonian; Li, Zhaoming; Hu, Junbo; Wang, Jing

    2012-12-01

    This study examined the role of EMP-1 in tumorigenesis of non-small cell lung carcinoma (NSCLC) and the possible mechanism. Specimens were collected from 28 patients with benign lung diseases and 28 with NSCLC, and immunohistochemically detected to evaluate the correlation of EMP-1 expression to the clinical features of NSCLC. Recombinant adenovirus was constructed to over-express EMP-1 and then infect PC9 cells. Cell proliferation was measured by Ki67 staining. Western blotting was performed to examine the effect of EMP-1 on the PI3K/AKT signaling. Moreover, tumor xenografts were established by subcutaneous injection of PC9 cell suspension (about 5×10(7)/mL in 100 μL of PBS) into the right hind limbs of athymic nude mice. The results showed EMP-1 was significantly up-regulated in NSCLC patients as compared with those with benign lung diseases. Over-expression of EMP-1 promoted proliferation of PC9 cells, which coincided with the activation of the PI3K/AKT pathway. EMP-1 promoted the growth of xenografts of PC9 cells in athymic nude mice. It was concluded that EMP-1 expression may contribute to the development and progress of NSCLC by activating PI3K/AKT pathway.

  18. HSPB1 Inhibits the Endothelial-to-Mesenchymal Transition to Suppress Pulmonary Fibrosis and Lung Tumorigenesis.

    Science.gov (United States)

    Choi, Seo-Hyun; Nam, Jae-Kyung; Kim, Bu-Yeo; Jang, Junho; Jin, Young-Bae; Lee, Hae-June; Park, Seungwoo; Ji, Young Hoon; Cho, Jaeho; Lee, Yoon-Jin

    2016-03-01

    The endothelial-to-mesenchymal transition (EndMT) contributes to cancer, fibrosis, and other pathologic processes. However, the underlying mechanisms are poorly understood. Endothelial HSP1 (HSPB1) protects against cellular stress and has been implicated in cancer progression and pulmonary fibrosis. In this study, we investigated the role of HSPB1 in mediating the EndMT during the development of pulmonary fibrosis and lung cancer. HSPB1 silencing in human pulmonary endothelial cells accelerated emergence of the fibrotic phenotype after treatment with TGFβ or other cytokines linked to pulmonary fibrosis, suggesting that HSPB1 maintains endothelial cell identity. In mice, endothelial-specific overexpression of HSPB1 was sufficient to inhibit pulmonary fibrosis by blocking the EndMT. Conversely, HSPB1 depletion in a mouse model of lung tumorigenesis induced the EndMT. In clinical specimens of non-small cell lung cancer, HSPB1 expression was absent from tumor endothelial cells undergoing the EndMT. Our results showed that HSPB1 regulated the EndMT in lung fibrosis and cancer, suggesting that HSPB1-targeted therapeutic strategies may be applicable for treating an array of fibrotic diseases.

  19. Oncogenic AKT1(E17K) mutation induces mammary hyperplasia but prevents HER2-driven tumorigenesis.

    Science.gov (United States)

    Mancini, Maria L; Lien, Evan C; Toker, Alex

    2016-04-05

    One of the most frequently deregulated signaling pathways in breast cancer is the PI 3-K/Akt cascade. Genetic lesions are commonly found in PIK3CA, PTEN, and AKT, which lead to excessive and constitutive activation of Akt and downstream signaling that results in uncontrolled proliferation and increased cellular survival. One such genetic lesion is the somatic AKT1(E17K) mutation, which has been identified in 4-8% of breast cancer patients. To determine how this mutation contributes to mammary tumorigenesis, we constructed a genetically engineered mouse model that conditionally expresses human AKT1(E17K) in the mammary epithelium. Although AKT1(E17K) is only weakly constitutively active and does not promote proliferation in vitro, it is capable of escaping negative feedback inhibition to exhibit sustained signaling dynamics in vitro. Consistently, both virgin and multiparous AKT1(E17K) mice develop mammary gland hyperplasia that do not progress to carcinoma. This hyperplasia is accompanied by increased estrogen receptor expression, although exposure of the mice to estrogen does not promote tumor development. Moreover, AKT1(E17K) prevents HER2-driven mammary tumor formation, in part through negative feedback inhibition of RTK signaling. Analysis of TCGA breast cancer data revealed that the mRNA expression, total protein levels, and phosphorylation of various RTKs are decreased in human tumors harboring AKT1(E17K).

  20. Gpr177 deficiency impairs mammary development and prohibits Wnt-induced tumorigenesis.

    Science.gov (United States)

    Maruyama, Eri Ohfuchi; Yu, H-M Ivy; Jiang, Ming; Fu, Jiang; Hsu, Wei

    2013-01-01

    Aberrant regulation of the Wnt pathway, essential for various developmental processes, is tightly linked to human breast cancers. By hijacking this evolutionary conserved signaling pathway, cancer cells acquire sustaining proliferation ability, leading to modification of physiologic properties necessary for tumor initiation and progression. An enormous wealth of knowledge on the importance of Wnt signaling in breast development and cancer has been obtained, but the cell types responsible for production of this proliferative signal operating within normal and malignant tissues remains poorly understood. Here we report that Wnt production mediated by Gpr177 is essential for mammary morphogenesis. The loss of Gpr177 interferes with mammary stem cells, leading to deficiencies in cell proliferation and differentiation. Genetic analysis further demonstrates an indispensable role of Gpr177 in Wnt-induced tumorigenesis. The Gpr177-deficiency mice are resistant to malignant transformation. This study not only demonstrates the necessity of Wnt in mammary organogenesis but also provides a proof-of-principle for targeting of Gpr177 as a potential new treatment for human diseases with aberrant Wnt stimulation.

  1. Gpr177 deficiency impairs mammary development and prohibits Wnt-induced tumorigenesis.

    Directory of Open Access Journals (Sweden)

    Eri Ohfuchi Maruyama

    Full Text Available Aberrant regulation of the Wnt pathway, essential for various developmental processes, is tightly linked to human breast cancers. By hijacking this evolutionary conserved signaling pathway, cancer cells acquire sustaining proliferation ability, leading to modification of physiologic properties necessary for tumor initiation and progression. An enormous wealth of knowledge on the importance of Wnt signaling in breast development and cancer has been obtained, but the cell types responsible for production of this proliferative signal operating within normal and malignant tissues remains poorly understood. Here we report that Wnt production mediated by Gpr177 is essential for mammary morphogenesis. The loss of Gpr177 interferes with mammary stem cells, leading to deficiencies in cell proliferation and differentiation. Genetic analysis further demonstrates an indispensable role of Gpr177 in Wnt-induced tumorigenesis. The Gpr177-deficiency mice are resistant to malignant transformation. This study not only demonstrates the necessity of Wnt in mammary organogenesis but also provides a proof-of-principle for targeting of Gpr177 as a potential new treatment for human diseases with aberrant Wnt stimulation.

  2. Obesity-dependent changes in interstitial ECM mechanics promote breast tumorigenesis

    Science.gov (United States)

    Seo, Bo Ri; Bhardwaj, Priya; Choi, Siyoung; Gonzalez, Jacqueline; Andresen Eguiluz, Roberto C.; Wang, Karin; Mohanan, Sunish; Morris, Patrick G.; Du, Baoheng; Zhou, Xi K.; Vahdat, Linda T.; Verma, Akanksha; Elemento, Olivier; Hudis, Clifford A.; Williams, Rebecca M.; Gourdon, Delphine; Dannenberg, Andrew J.; Fischbach, Claudia

    2016-01-01

    Obesity and extracellular matrix (ECM) density are considered independent risk and prognostic factors for breast cancer. Whether they are functionally linked is uncertain. We investigated the hypothesis that obesity enhances local myofibroblast content in mammary adipose tissue and that these stromal changes increase malignant potential by enhancing interstitial ECM stiffness. Indeed, mammary fat of both diet- and genetically induced mouse models of obesity were enriched for myofibroblasts and stiffness-promoting ECM components. These differences were related to varied adipose stromal cell (ASC) characteristics because ASCs isolated from obese mice contained more myofibroblasts and deposited denser and stiffer ECMs relative to ASCs from lean control mice. Accordingly, decellularized matrices from obese ASCs stimulated mechanosignaling and thereby the malignant potential of breast cancer cells. Finally, the clinical relevance and translational potential of our findings were supported by analysis of patient specimens and the observation that caloric restriction in a mouse model reduces myofibroblast content in mammary fat. Collectively, these findings suggest that obesity-induced interstitial fibrosis promotes breast tumorigenesis by altering mammary ECM mechanics with important potential implications for anticancer therapies. PMID:26290412

  3. Oxidative stress and lectin-like ox-LDL-receptor LOX-1 in atherogenesis and tumorigenesis.

    Science.gov (United States)

    Lu, Jingjun; Mitra, Sona; Wang, Xianwei; Khaidakov, Magomed; Mehta, Jawahar L

    2011-10-15

    Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) has been identified as a major receptor for oxidized low-density lipoprotein (ox-LDL) in endothelial cells, monocytes, platelets, cardiomyocytes, and vascular smooth muscle cells. Its expression is minimal under physiological conditions but can be induced under pathological conditions. The upregulation of LOX-1 by ox-LDL appears to be important for physiologic processes, such as endothelial cell proliferation, apoptosis, and endothelium remodeling. Pathophysiologic effects of ox-LDL in atherogenesis have also been firmly established, including endothelial cell dysfunction, smooth muscle cell growth and migration, monocyte transformation into macrophages, and finally platelet aggregation-seen in atherogenesis. Recent studies show a positive correlation between increased serum ox-LDL levels and an increased risk of colon, breast, and ovarian cancer. As in atherosclerosis, ox-LDL and its receptor LOX-1 activate the inflammatory pathway through nuclear factor-kappa B, leading to cell transformation. LOX-1 is important for maintaining the transformed state in developmentally diverse cancer cell lines and for tumor growth, suggesting a molecular connection between atherogenesis and tumorigenesis.

  4. Genomic Characterization of Esophageal Squamous Cell Carcinoma Reveals Critical Genes Underlying Tumorigenesis and Poor Prognosis

    Science.gov (United States)

    Qin, Hai-De; Liao, Xiao-Yu; Chen, Yuan-Bin; Huang, Shao-Yi; Xue, Wen-Qiong; Li, Fang-Fang; Ge, Xiao-Song; Liu, De-Qing; Cai, Qiuyin; Long, Jirong; Li, Xi-Zhao; Hu, Ye-Zhu; Zhang, Shao-Dan; Zhang, Lan-Jun; Lehrman, Benjamin; Scott, Alan F.; Lin, Dongxin; Zeng, Yi-Xin; Shugart, Yin Yao; Jia, Wei-Hua

    2016-01-01

    The genetic mechanisms underlying the poor prognosis of esophageal squamous cell carcinoma (ESCC) are not well understood. Here, we report somatic mutations found in ESCC from sequencing 10 whole-genome and 57 whole-exome matched tumor-normal sample pairs. Among the identified genes, we characterized mutations in VANGL1 and showed that they accelerated cell growth in vitro. We also found that five other genes, including three coding genes (SHANK2, MYBL2, FADD) and two non-coding genes (miR-4707-5p, PCAT1), were involved in somatic copy-number alterations (SCNAs) or structural variants (SVs). A survival analysis based on the expression profiles of 321 individuals with ESCC indicated that these genes were significantly associated with poorer survival. Subsequently, we performed functional studies, which showed that miR-4707-5p and MYBL2 promoted proliferation and metastasis. Together, our results shed light on somatic mutations and genomic events that contribute to ESCC tumorigenesis and prognosis and might suggest therapeutic targets. PMID:27058444

  5. JAC, a direct target of oncogenic transcription factor Jun, is involved in cell transformation and tumorigenesis.

    Science.gov (United States)

    Hartl, M; Reiter, F; Bader, A G; Castellazzi, M; Bister, K

    2001-11-20

    Using subtractive hybridization techniques, we have isolated a gene termed JAC that is strongly and specifically activated in avian fibroblasts transformed by the v-jun oncogene of avian sarcoma virus 17 (ASV17), but not in cells transformed by other oncogenic agents. Furthermore, JAC is highly expressed in cell lines derived from jun-induced avian fibrosarcomas. Kinetic analysis using a doxycycline-controlled conditional cell transformation system showed that expression of the 0.8-kb JAC mRNA is induced rapidly upon activation of the oncogenic v-jun allele. Nucleotide sequence analysis and transcriptional mapping revealed that the JAC gene contains two exons, with the longest ORF confined to exon 2. The deduced 68-amino acid chicken JAC protein is rich in cysteine residues and displays 37% sequence identity to mammalian high-sulfur keratin-associated proteins. The promoter region of JAC contains a consensus (5'-TGACTCA-3') and a nonconsensus (5'-TGAGTAA-3') AP-1 binding site in tandem, which are both specifically bound by the Gag-Jun hybrid protein encoded by ASV17. Mutational analysis revealed that the two AP-1 sites confer strong transcriptional activation by Gag-Jun in a synergistic manner. Ectopic expression of JAC in avian fibroblasts leads to anchorage-independent growth, strongly suggesting that deregulation of JAC is an essential event in jun-induced cell transformation and tumorigenesis.

  6. Telomeres and Telomerase: Role in Marek’s Disease Virus Pathogenesis, Integration and Tumorigenesis

    Directory of Open Access Journals (Sweden)

    Ahmed Kheimar

    2017-07-01

    Full Text Available Telomeres protect the ends of vertebrate chromosomes from deterioration and consist of tandem nucleotide repeats (TTAGGGn that are associated with a number of proteins. Shortening of the telomeres occurs during genome replication, thereby limiting the replication potential of somatic cells. To counteract this shortening, vertebrates encode the telomerase complex that maintains telomere length in certain cell types via de novo addition of telomeric repeats. Several herpesviruses, including the highly oncogenic alphaherpesvirus Marek’s disease virus (MDV, harbor telomeric repeats (TMR identical to the host telomere sequences at the ends of their linear genomes. These TMR facilitate the integration of the MDV genome into host telomeres during latency, allowing the virus to persist in the host for life. Integration into host telomeres is critical for disease and tumor induction by MDV, but also enables efficient reactivation of the integrated virus genome. In addition to the TMR, MDV also encodes a telomerase RNA subunit (vTR that shares 88% sequence identity with the telomerase RNA in chicken (chTR. vTR is highly expressed during all stages of the virus lifecycle, enhances telomerase activity and plays an important role in MDV-induced tumor formation. This review will focus on the recent advances in understanding the role of viral TMR and vTR in MDV pathogenesis, integration and tumorigenesis.

  7. Telomeres and Telomerase: Role in Marek's Disease Virus Pathogenesis, Integration and Tumorigenesis.

    Science.gov (United States)

    Kheimar, Ahmed; Previdelli, Renato L; Wight, Darren J; Kaufer, Benedikt B

    2017-07-04

    Telomeres protect the ends of vertebrate chromosomes from deterioration and consist of tandem nucleotide repeats (TTAGGG)n that are associated with a number of proteins. Shortening of the telomeres occurs during genome replication, thereby limiting the replication potential of somatic cells. To counteract this shortening, vertebrates encode the telomerase complex that maintains telomere length in certain cell types via de novo addition of telomeric repeats. Several herpesviruses, including the highly oncogenic alphaherpesvirus Marek's disease virus (MDV), harbor telomeric repeats (TMR) identical to the host telomere sequences at the ends of their linear genomes. These TMR facilitate the integration of the MDV genome into host telomeres during latency, allowing the virus to persist in the host for life. Integration into host telomeres is critical for disease and tumor induction by MDV, but also enables efficient reactivation of the integrated virus genome. In addition to the TMR, MDV also encodes a telomerase RNA subunit (vTR) that shares 88% sequence identity with the telomerase RNA in chicken (chTR). vTR is highly expressed during all stages of the virus lifecycle, enhances telomerase activity and plays an important role in MDV-induced tumor formation. This review will focus on the recent advances in understanding the role of viral TMR and vTR in MDV pathogenesis, integration and tumorigenesis.

  8. Effects of hemin and nitrite on intestinal tumorigenesis in the A/J Min/+ mouse model.

    Directory of Open Access Journals (Sweden)

    Marianne Sødring

    Full Text Available Red and processed meats are considered risk factors for colorectal cancer (CRC; however, the underlying mechanisms are still unclear. One cause for the potential link between CRC and meat is the heme iron in red meat. Two pathways by which heme and CRC promotion may be linked have been suggested: fat peroxidation and N-nitrosation. In the present work we have used the novel A/J Min/+ mouse model to test the effects of dietary hemin (a model of red meat, and hemin in combination with nitrite (a model of processed meat on intestinal tumorigenesis. Mice were fed a low Ca2+ and vitamin D semi-synthetic diet with added hemin and/or nitrite for 8 weeks post weaning, before termination followed by excision and examination of the intestinal tract. Our results indicate that dietary hemin decreased the number of colonic lesions in the A/J Min/+ mouse. However, our results also showed that the opposite occurred in the small intestine, where dietary hemin appeared to stimulate tumor growth. Furthermore, we find that nitrite, which did not have an effect in the colon, appeared to have a suppressive effect on tumor growth in the small intestine.

  9. Oligonucleotide microarray identifies genes differentially expressed during tumorigenesis of DMBA-induced pancreatic cancer in rats.

    Science.gov (United States)

    Guo, Jun-Chao; Li, Jian; Yang, Ying-Chi; Zhou, Li; Zhang, Tai-Ping; Zhao, Yu-Pei

    2013-01-01

    The extremely dismal prognosis of pancreatic cancer (PC) is attributed, at least in part, to lack of early diagnosis. Therefore, identifying differentially expressed genes in multiple steps of tumorigenesis of PC is of great interest. In the present study, a 7,12-dimethylbenzanthraene (DMBA)-induced PC model was established in male Sprague-Dawley rats. The gene expression profile was screened using an oligonucleotide microarray, followed by real-time quantitative polymerase chain reaction (qRT-PCR) and immunohistochemical staining validation. A total of 661 differentially expressed genes were identified in stages of pancreatic carcinogenesis. According to GO classification, these genes were involved in multiple molecular pathways. Using two-way hierarchical clustering analysis, normal pancreas, acute and chronic pancreatitis, PanIN, early and advanced pancreatic cancer were completely discriminated. Furthermore, 11 upregulated and 142 downregulated genes (probes) were found by Mann-Kendall trend Monotone test, indicating homologous genes of rat and human. The qRT-PCR and immunohistochemistry analysis of CXCR7 and UBe2c, two of the identified genes, confirmed the microarray results. In human PC cell lines, knockdown of CXCR7 resulted in decreased migration and invasion. Collectively, our data identified several promising markers and therapeutic targets of PC based on a comprehensive screening and systemic validation.

  10. Absence of ERK5/MAPK7 delays tumorigenesis in Atm-/- mice.

    Science.gov (United States)

    Granados-Jaén, Alba; Angulo-Ibáñez, Maria; Rovira-Clavé, Xavier; Gamez, Celina Paola Vasquez; Soriano, Francesc X; Reina, Manuel; Espel, Enric

    2016-11-15

    Ataxia-telangiectasia mutated (ATM) is a cell cycle checkpoint kinase that upon activation by DNA damage leads to cell cycle arrest and DNA repair or apoptosis. The absence of Atm or the occurrence of loss-of-function mutations in Atm predisposes to tumorigenesis. MAPK7 has been implicated in numerous types of cancer with pro-survival and pro-growth roles in tumor cells, but its functional relation with tumor suppressors is not clear. In this study, we show that absence of MAPK7 delays death due to spontaneous tumor development in Atm-/- mice. Compared with Atm-/- thymocytes, Mapk7-/-Atm-/- thymocytes exhibited an improved response to DNA damage (increased phosphorylation of H2AX) and a restored apoptotic response after treatment of mice with ionizing radiation. These findings define an antagonistic function of ATM and MAPK7 in the thymocyte response to DNA damage, and suggest that the lack of MAPK7 inhibits thymic lymphoma growth in Atm-/- mice by partially restoring the DNA damage response in thymocytes.

  11. GATA4 is a critical regulator of gonadectomy-induced adrenocortical tumorigenesis in mice.

    Science.gov (United States)

    Krachulec, Justyna; Vetter, Melanie; Schrade, Anja; Löbs, Ann-Kathrin; Bielinska, Malgorzata; Cochran, Rebecca; Kyrönlahti, Antti; Pihlajoki, Marjut; Parviainen, Helka; Jay, Patrick Y; Heikinheimo, Markku; Wilson, David B

    2012-06-01

    In response to gonadectomy certain inbred mouse strains develop sex steroidogenic adrenocortical neoplasms. One of the hallmarks of neoplastic transformation is expression of GATA4, a transcription factor normally present in gonadal but not adrenal steroidogenic cells of the adult mouse. To show that GATA4 directly modulates adrenocortical tumorigenesis and is not merely a marker of gonadal-like differentiation in the neoplasms, we studied mice with germline or conditional loss-of-function mutations in the Gata4 gene. Germline Gata4 haploinsufficiency was associated with attenuated tumor growth and reduced expression of sex steroidogenic genes in the adrenal glands of ovariectomized B6D2F1 and B6AF1 mice. At 12 months after ovariectomy, wild-type B6D2F1 mice had biochemical and histological evidence of adrenocortical estrogen production, whereas Gata4(+/-) B6D2F1 mice did not. Germline Gata4 haploinsufficiency exacerbated the secondary phenotype of postovariectomy obesity in B6D2F1 mice, presumably by limiting ectopic estrogen production in the adrenal glands. Amhr2-cre-mediated deletion of floxed Gata4 (Gata4(F)) in nascent adrenocortical neoplasms of ovariectomized B6.129 mice reduced tumor growth and the expression of gonadal-like markers in a Gata4(F) dose-dependent manner. We conclude that GATA4 is a key modifier of gonadectomy-induced adrenocortical neoplasia, postovariectomy obesity, and sex steroidogenic cell differentiation.

  12. SIRT1 and Tumorigenesis%SIRT1与肿瘤发生

    Institute of Scientific and Technical Information of China (English)

    赵志强; 毛文琼

    2011-01-01

    Sirtuin l(SIRT1)inactivates proteins involved in tumor suppression and DNA damage repair )by deacetylation and it has long been considered as a tumor promoter. However, recent studies demonstrated that SIRT1 expression levels are reduced in some other types of cancers, and that SIRT1 deficiency results in genetic instability and tumorigenesis,while overexpression of SIRT1 attenuates cancer formation. The dual role that SIRT1 plays may depend on the temporal and special distribution of different SIRT1 upand downstream factors in different tissue contexts.%SIRT1(sirtuin 1)通过对肿瘤抑制蛋白和DNA损伤修复蛋白去乙酰化而使之失活。因此,SIRT1早期被认为是肿瘤促进因子。近来研究又表明SIRT1在某些肿瘤中表达降低且SIRT1缺乏导致遗传不稳定和肿瘤发生。超表达SIRT1可降低癌变风险。SIRT1的这种双重作用可能与其组织中SIRT1上游和下游因子的时空分布不同有关。

  13. Choroid plexus papillomas: advances in molecular biology and understanding of tumorigenesis.

    Science.gov (United States)

    Safaee, Michael; Oh, Michael C; Bloch, Orin; Sun, Matthew Z; Kaur, Gurvinder; Auguste, Kurtis I; Tihan, Tarik; Parsa, Andrew T

    2013-03-01

    Choroid plexus papillomas are rare, benign tumors originating from the choroid plexus. Although generally found within the ventricular system, they can arise ectopically in the brain parenchyma or disseminate throughout the neuraxis. We sought to review recent advances in our understanding of the molecular biology and oncogenic pathways associated with this disease. A comprehensive PubMed literature review was conducted to identify manuscripts discussing the clinical, molecular, and genetic features of choroid plexus papillomas. Articles concerning diagnosis, treatment, and long-term patient outcomes were also reviewed. The introduction of atypical choroid plexus papilloma as a distinct entity has increased the need for accurate histopathologic diagnosis. Advances in immunohistochemical staining have improved our ability to differentiate choroid plexus papillomas from other intracranial tumors or metastatic lesions using combinations of key markers and mitotic indices. Recent findings have implicated Notch3 signaling, the transcription factor TWIST1, platelet-derived growth factor receptor, and the tumor necrosis factor-related apoptosis-inducing ligand pathway in choroid plexus papilloma tumorigenesis. A combination of commonly occurring chromosomal duplications and deletions has also been identified. Surgical resection remains the standard of care, although chemotherapy and radiotherapy may be considered for recurrent or metastatic lesions. While generally considered benign, these tumors possess a complex biology that sheds insight into other choroid plexus tumors, particularly malignant choroid plexus carcinomas. Improving our understanding of the molecular biology, genetics, and oncogenic pathways associated with this tumor will allow for the development of targeted therapies and improved outcomes for patients with this disease.

  14. Intramyocardial transplantation of undifferentiated rat induced pluripotent stem cells causes tumorigenesis in the heart.

    Directory of Open Access Journals (Sweden)

    Yuzhen Zhang

    Full Text Available BACKGROUND: Induced pluripotent stem cells (iPSCs are a novel candidate for use in cardiac stem cell therapy. However, their intrinsic tumorigenicity requires further investigation prior to use in a clinical setting. In this study we investigated whether undifferentiated iPSCs are tumorigenic after intramyocardial transplantation into immunocompetent allogeneic recipients. METHODOLOGY/PRINCIPAL FINDINGS: We transplanted 2 × 10(4, 2 × 10(5, or 2 × 10(6 cells from the established rat iPSC line M13 intramyocardially into intact or infarcted hearts of immunocompetent allogeneic rats. Transplant duration was 2, 4, or 6 weeks. Histological examination with hematoxylin-eosin staining confirmed that undifferentiated rat iPSCs could generate heterogeneous tumors in both intracardiac and extracardiac sites. Furthermore, tumor incidence was independent of cell dose, transplant duration, and the presence or absence of myocardial infarction. CONCLUSIONS/SIGNIFICANCE: Our study demonstrates that allogeneic iPSC transplantation in the heart will likely result in in situ tumorigenesis, and that cells leaked from the beating heart are a potential source of tumor spread, underscoring the importance of evaluating the safety of future iPSC therapy for cardiac disease.

  15. Control of Paneth Cell Fate, Intestinal Inflammation, and Tumorigenesis by PKCλ/ι

    Directory of Open Access Journals (Sweden)

    Yuki Nakanishi

    2016-09-01

    Full Text Available Paneth cells are a highly specialized population of intestinal epithelial cells located in the crypt adjacent to Lgr5+ stem cells, from which they differentiate through a process that requires downregulation of the Notch pathway. Their ability to store and release antimicrobial peptides protects the host from intestinal pathogens and controls intestinal inflammation. Here, we show that PKCλ/ι is required for Paneth cell differentiation at the level of Atoh1 and Gfi1, through the control of EZH2 stability by direct phosphorylation. The selective inactivation of PKCλ/ι in epithelial cells results in the loss of mature Paneth cells, increased apoptosis and inflammation, and enhanced tumorigenesis. Importantly, PKCλ/ι expression in human Paneth cells decreases with progression of Crohn’s disease. Kaplan-Meier survival analysis of colorectal cancer (CRC patients revealed that low PRKCI levels correlated with significantly worse patient survival rates. Therefore, PKCλ/ι is a negative regulator of intestinal inflammation and cancer through its role in Paneth cell homeostasis.

  16. MicroRNA-24 Modulates Aflatoxin B1-Related Hepatocellular Carcinoma Prognosis and Tumorigenesis

    Directory of Open Access Journals (Sweden)

    Yi-Xiao Liu

    2014-01-01

    Full Text Available MicroRNA-24 (miR-24 may be involved in neoplastic process; however, the role of this microRNA in the hepatocellular carcinoma (HCC related to aflatoxin B1 (AFB1 has not been well elaborated. Here, we tested miR-24 expression in 207 pathology-diagnosed HCC cases from high AFB1 exposure areas and HCC cells. We found that miR-24 was upregulated in HCC tumor tissues relative to adjacent noncancerous tissue samples, and that the high expression of miR-24 was significantly correlated with larger tumor size, higher microvessel density, and tumor dedifferentiation. Additionally, this microRNA overexpression modified the recurrence-free survival (relative hazard ratio [HR], 4.75; 95% confidence interval [CI], 2.66–8.47 and overall survival (HR=3.58, 95% CI = 2.34–5.46 of HCC patients. Furthermore, we observed some evidence of joint effects between miR-24 and AFB1 exposure on HCC prognosis. Functionally, miR-24 overexpression progressed tumor cells proliferation, inhibited cell apoptosis, and developed the formation of AFB1-DNA adducts. These results indicate for the first time that miR-24 may modify AFB1-related HCC prognosis and tumorigenesis.

  17. Protein Kinase C alpha (PKCα) dependent signaling mediates endometrial cancer cell growth and tumorigenesis

    Science.gov (United States)

    Haughian, James M.; Reno, Elaine M.; Thorne, Alicia M.; Bradford, Andrew P.

    2009-01-01

    Endometrial cancer is the most common invasive gynecologic malignancy, yet molecular mechanisms and signaling pathways underlying its etiology and pathophysiology remain poorly characterized. We sought to define a functional role for the protein kinase C (PKC) isoform, PKCα, in an established cell model of endometrial adenocarcinoma. Ishikawa cells depleted of PKCα protein grew slower, formed fewer colonies in anchorage-independent growth assays and exhibited impaired xenograft tumor formation in nude mice. Consistent with impaired growth, PKCα knockdown increased levels of the cyclin dependent kinase (CDK) inhibitors p21Cip1/WAF1 (p21) and p27Kip1 (p27). Despite the absence of functional phosphatase and tensin homologue (PTEN) protein in Ishikawa cells, PKCα knockdown reduced Akt phosphorylation at serine 473 and concomitantly inhibited phosphorylation of the Akt target, glycogen synthase kinase-3β (GSK-3β). PKCα knockdown also resulted in decreased basal ERK phosphorylation and attenuated ERK activation following EGF stimulation. p21 and p27 expression was not increased by treatment of Ishikawa cells with ERK and Akt inhibitors, suggesting PKCα regulates CDK expression independently of Akt and ERK. Immunohistochemical analysis of grade 1 endometrioid adenocarcinoma revealed aberrant PKCα expression, with foci of elevated PKCα staining, not observed in normal endometrium. These studies demonstrate a critical role for PKCα signaling in endometrial tumorigenesis by regulating expression of CDK inhibitors p21 and p27 and activation of Akt and ERK dependent proliferative pathways. Thus, targeting PKCα may provide novel therapeutic options in endometrial tumors. PMID:19672862

  18. Dmp1α inhibits HER2/neu-induced mammary tumorigenesis.

    Directory of Open Access Journals (Sweden)

    Elizabeth A Fry

    Full Text Available Our recent study shows a pivotal role of Dmp1 in quenching hyperproliferative signals from HER2 to the Arf-p53 pathway as a safety mechanism to prevent breast carcinogenesis. To directly demonstrate the role of Dmp1 in preventing HER2/neu-driven oncogenic transformation, we established Flag-Dmp1α transgenic mice (MDTG under the control of the mouse mammary tumor virus (MMTV promoter. The mice were viable but exhibited poorly developed mammary glands with markedly reduced milk production; thus more than half of parous females were unable to support the lives of new born pups. The mammary glands of the MDTG mice had very low Ki-67 expression but high levels of Arf, Ink4a, p53, and p21(Cip1, markers of senescence and accelerated aging. In all strains of generated MDTG;neu mice, tumor development was significantly delayed with decreased tumor weight. Tumors from MDTG;neu mice expressed Flag-Dmp1α and Ki-67 in a mutually exclusive fashion indicating that transgenic Dmp1α prevented tumor growth in vivo. Genomic DNA analyses showed that the Dmp1α transgene was partially lost in half of the MDTG;neu tumors, and Western blot analyses showed Dmp1α protein downregulation in 80% of the cases. Our data demonstrate critical roles of Dmp1 in preventing mammary tumorigenesis and raise the possibility of treating breast cancer by restoring Dmp1α expression.

  19. Cbx8 Acts Non-canonically with Wdr5 to Promote Mammary Tumorigenesis.

    Science.gov (United States)

    Chung, Chi-Yeh; Sun, Zhen; Mullokandov, Gavriel; Bosch, Almudena; Qadeer, Zulekha A; Cihan, Esma; Rapp, Zachary; Parsons, Ramon; Aguirre-Ghiso, Julio A; Farias, Eduardo F; Brown, Brian D; Gaspar-Maia, Alexandre; Bernstein, Emily

    2016-07-12

    Chromatin-mediated processes influence the development and progression of breast cancer. Using murine mammary carcinoma-derived tumorspheres as a functional readout for an aggressive breast cancer phenotype, we performed a loss-of-function screen targeting 60 epigenetic regulators. We identified the Polycomb protein Cbx8 as a key regulator of mammary carcinoma both in vitro and in vivo. Accordingly, Cbx8 is overexpressed in human breast cancer and correlates with poor survival. Our genomic analyses revealed that Cbx8 positively regulates Notch signaling by maintaining H3K4me3 levels on Notch-network gene promoters. Ectopic expression of Notch1 partially rescues tumorsphere formation in Cbx8-depleted cells. We find that Cbx8 associates with non-PRC1 complexes containing the H3K4 methyltransferase complex component WDR5, which together regulate Notch gene expression. Thus, our study implicates a key non-canonical role for Cbx8 in promoting breast tumorigenesis.

  20. Cbx8 Acts Non-canonically with Wdr5 to Promote Mammary Tumorigenesis

    Directory of Open Access Journals (Sweden)

    Chi-Yeh Chung

    2016-07-01

    Full Text Available Chromatin-mediated processes influence the development and progression of breast cancer. Using murine mammary carcinoma-derived tumorspheres as a functional readout for an aggressive breast cancer phenotype, we performed a loss-of-function screen targeting 60 epigenetic regulators. We identified the Polycomb protein Cbx8 as a key regulator of mammary carcinoma both in vitro and in vivo. Accordingly, Cbx8 is overexpressed in human breast cancer and correlates with poor survival. Our genomic analyses revealed that Cbx8 positively regulates Notch signaling by maintaining H3K4me3 levels on Notch-network gene promoters. Ectopic expression of Notch1 partially rescues tumorsphere formation in Cbx8-depleted cells. We find that Cbx8 associates with non-PRC1 complexes containing the H3K4 methyltransferase complex component WDR5, which together regulate Notch gene expression. Thus, our study implicates a key non-canonical role for Cbx8 in promoting breast tumorigenesis.

  1. The circadian mutation PER2(S662G) is linked to cell cycle progression and tumorigenesis.

    Science.gov (United States)

    Gu, X; Xing, L; Shi, G; Liu, Z; Wang, X; Qu, Z; Wu, X; Dong, Z; Gao, X; Liu, G; Yang, L; Xu, Y

    2012-03-01

    Circadian oscillation and cell cycle progression are the two most essential rhythmic events present in almost all organisms. Circadian rhythms keep track of time and provide temporal regulation with a period of about 24 h. The cell cycle is optimized for growth and division, but not for time keeping. Circadian gated cell divisions are observed in nearly all organisms. However, the implications of this coupling to the physiology of mammals are unknown. A mutation (S662G) in the clock protein PERIOD2 (PER2) is responsible for familial advanced sleep phase syndrome in which sleep onset occurs in the early evening and wakefulness occurs in the early morning. Here, we provide evidence that the PER2(S662) mutation leads to enhanced resistance to X-ray-induced apoptosis and increased E1A- and RAS-mediated oncogenic transformation. Accordingly, the PER2(S662) mutation affects tumorigenesis in cancer-sensitized p53(R172H/+) mice. Finally, analyzing the clock-controlled cell cycle genes p21, c-Myc, Cyclin D1 and p27, we found that the relative phases between p21 and Cyclin D expression profiles have been changed significantly in these Per2 allele mutant mouse embryonic fibroblasts. This key role of the Per2-mediated phase alteration of p21 provides what we believe to be a novel mechanism in understanding cell cycle progression, its plasticity and its resistance to interference.

  2. T-cell activation promotes tumorigenesis in inflammation-associated cancer

    Directory of Open Access Journals (Sweden)

    Lairmore Michael

    2009-12-01

    Full Text Available Abstract Chronic inflammation has long been associated with a wide range of malignancies, is now widely accepted as a risk factor for development of cancer, and has been implicated as a promoter of a variety of cancers including hematopoietic malignancies. We have described a mouse model uniquely suited to examine the link between inflammation and lymphoma in which the Tax oncogene, expressed in activated T and NK cells, perpetuates chronic inflammation that begins as microscopic intraepithelial lesions and develops into inflammatory nodules, subcutaneous tumors, and large granular lymphocytic leukemia. The use of bioluminescent imaging in these mice has expanded our ability to interrogate aspects of inflammation and tumorigenesis non-invasively. Here we demonstrate that bioluminescence induction in these mice correlated with inflammation resulting from wounding, T cell activation, and exposure to chemical agents. In experiments in which long-term effects of inflammation on disease outcome were monitored, the development of lymphoma was promoted by an inflammatory stimulus. Finally we demonstrated that activation of T-cells in T-cell receptor (TCR transgenic TAX-LUC animals dramatically exacerbated the development of subcutaneous TCR- CD16+ LGL tumors. The role of activated T-cells and acquired immunity in inflammation-associated cancers is broadly applicable to hematopoietic malignancies, and we propose these mice will be of use in dissecting mechanisms by which activated T-cells promote lymphomagenesis in vivo.

  3. Telomere regulation during ageing and tumorigenesis of the grey mouse lemur.

    Science.gov (United States)

    Trochet, Delphine; Mergui, Xénia; Ivkovic, Ivana; Porreca, Rosa Maria; Gerbault-Seureau, Michèle; Sidibe, Assitan; Richard, Florence; Londono-Vallejo, Arturo; Perret, Martine; Aujard, Fabienne; Riou, Jean-François

    2015-06-01

    Telomere erosion leading to replicative senescence has been well documented in human and anthropoid primates, and provides a clue against tumorigenesis. In contrast, other mammals, such as laboratory mice, with short lifespan and low body weight mass have different telomere biology without replicative senescence. We analyzed telomere biology in the grey mouse lemur, a small prosimian model with a relative long lifespan currently used in ageing research. We report an average telomere length by telomere restriction fragment (TRF) among the longest reported so far for a primate species (25-30 kb), but without detectable overall telomere shortening with ageing on blood samples. However, we demonstrate using universal STELA (Single Telomere Length Amplification) the existence of short telomeres, the increase of which, while correlating with ageing might be related to another mechanism than replicative senescence. We also found a low stringency of telomerase restriction in tissues and an ease to immortalize fibroblasts in vitro upon spontaneous telomerase activation. Finally, we describe the first grey mouse lemur cancer cell line showing a dramatic telomere shortening and high telomerase activity associated with polyploidy. Our overall results suggest that telomere biology in grey mouse lemur is an exception among primates, with at best a physiologically limited replicative telomere ageing and closest to that observed in small rodents.

  4. Electroporation markedly improves Sleeping Beauty transposon-induced tumorigenesis in mice.

    Science.gov (United States)

    Jung, S; Choi, H-J; Park, H-K; Jo, W; Jang, S; Ryu, J-E; Kim, W-J; Yu, E-S; Son, W-C

    2014-08-01

    The Sleeping Beauty (SB) transposon system is an important tool for genetic studies. It is used to insert a gene of interest into the host chromosome, thus enabling permanent gene expression. However, this system is less useful in higher eukaryotes because the transposition frequency is low. Efforts to improve the efficacy of the SB transposon system have focused on the method of gene delivery, but although electroporation has recently attracted much attention as an in vivo gene delivery tool, the simultaneous use of electroporation and the SB transposon system has not been studied for gene transfer in mice. In this study, electroporation was used in a model of SB transposon-induced insertional tumorigenesis. Electroporation increased the rate of tumor development to three times that of the control group. There was no difference in phenotype between tumors induced with the SB transposon system alone and those induced by the SB transposon and electroporation. Electroporation therefore may be an efficient means of improving the efficacy of gene transfer via the SB transposon system.

  5. PARP-1: Friend or Foe of DNA Damage and Repair in Tumorigenesis?

    Energy Technology Data Exchange (ETDEWEB)

    Swindall, Amanda F.; Stanley, Jennifer A. [Department of Radiation Oncology Comprehensive Cancer Center, University of Alabama at Birmingham School of Medicine, 176F HSROC Suite 2232B, 1700 6th Avenue South, Birmingham, AL 35249 (United States); Yang, Eddy S., E-mail: eyang@uab.edu [Department of Radiation Oncology Comprehensive Cancer Center, University of Alabama at Birmingham School of Medicine, 176F HSROC Suite 2232B, 1700 6th Avenue South, Birmingham, AL 35249 (United States); Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL 35249 (United States); Department of Pharmacology and Toxicology, University of Alabama at Birmingham, Birmingham, AL 35249 (United States)

    2013-07-26

    Oxidative stress induced by reactive oxygen species can result in DNA damage within cells and subsequently increase risk for carcinogenesis. This may be averted by repair of DNA damage through the base or nucleotide excision repair (BER/NER) pathways. PARP, a BER protein, is known for its role in DNA-repair. However, multiple lesions can occur within a small range of DNA, known as oxidative clustered DNA lesions (OCDLs), which are difficult to repair and may lead to the more severe DNA double-strand break (DSB). Inefficient DSB repair can then result in increased mutagenesis and neoplastic transformation. OCDLs occur more frequently within a variety of tumor tissues. Interestingly, PARP is highly expressed in several human cancers. Additionally, chronic inflammation may contribute to tumorigenesis through ROS-induced DNA damage. Furthermore, PARP can modulate inflammation through interaction with NFκB and regulating the expression of inflammatory signaling molecules. Thus, the upregulation of PARP may present a double-edged sword. PARP is needed to repair ROS-induced DNA lesions, but PARP expression may lead to increased inflammation via upregulation of NFκB signaling. Here, we discuss the role of PARP in the repair of oxidative damage versus the formation of OCDLs and speculate on the feasibility of PARP inhibition for the treatment and prevention of cancers by exploiting its role in inflammation.

  6. Overexpression of SAMD9 suppresses tumorigenesis and progression during non small cell lung cancer

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Qing; Yu, Tao; Ren, Yao-Yao; Gong, Ting; Zhong, Dian-Sheng, E-mail: zhongdsyx@126.com

    2014-11-07

    Highlights: • SAMD9 is down-regulated in human non-small cell lung cancer (NSCLC). • Knockdown of SAMD9 expression is increased the invasion, migration and proliferation in H1299 cells in vitro. • Overexpression of SAMD9 suppressed proliferation and invasion in A549 cells in vitro. • Depletion of SAMD9 increases tumor formation in vivo. - Abstract: The Sterile Alpha Motif Domain-containing 9 (SAMD9) gene has been recently emphasized during the discovery that it is expressed at a lower level in aggressive fibromatosis and some cases of breast and colon cancer, however, the underlying mechanisms are poorly understood. Here, we found that SAMD9 is down-regulated in human non-small cell lung cancer (NSCLC). Furthermore, knockdown of SAMD9 expression is increased the invasion, migration and proliferation in H1299 cells in vitro and overexpression of SAMD9 suppressed proliferation and invasion in A549 cells. Finally, depletion of SAMD9 increases tumor formation in vivo. Our results may provide a strategy for blocking NSCLC tumorigenesis and progression.

  7. The role of microRNAs in the tumorigenesis of ovarian cancer.

    Directory of Open Access Journals (Sweden)

    Gianpiero eDi Leva

    2013-06-01

    Full Text Available Epithelial ovarian cancer (EOC is a complex disease, with multiple histological subtypes recognized. There have been major advances in the understanding of the cellular and molecular biology of this human malignancy, however the survival rate of women with epithelial ovarian cancer has changed little since platinum based-treatment was introduced more than 30 years ago. Since 2006, an increasing number of studies have indicated an essential role for microRNAs in ovarian cancer tumorigenesis. Several microRNA profiling studies have shown that they associate with different aspects of ovarian cancer (tumor subtype, stage, histological grade, prognosis and therapy resistance and pointed to a critical role for microRNAs in the pathogenesis and progression of EOC. In this review, we discuss the current data concerning the accumulating evidence of the modulated expression of microRNAs in EOC, their role in diagnosis, prognosis and prediction of response to therapy. Given the heterogeneity of this disease, it is likely that increases in long-term survival might be also achieved by translating the recent insights of miRNAs involvement in EOC into novel targeted therapies that will have a major impact on the management of ovarian cancer.

  8. Characterization of a dominant-active STAT that promotes tumorigenesis in Drosophila

    Science.gov (United States)

    Ekas, Laura A.; Cardozo, Timothy J.; Flaherty, Maria Sol; McMillan, Elizabeth A.; Gonsalves, Foster C.; Bach, Erika A.

    2010-01-01

    Little is known about the molecular mechanisms by which STAT proteins promote tumorigenesis. Drosophila is an ideal system for investigating this issue, as there is a single STAT (Stat92E), and its hyperactivation causes overgrowths resembling human tumors. Here we report the first identification of a dominant-active Stat92E protein, Stat92EΔNΔC, which lacks both N- and C-termini. Mis-expression of Stat92EΔNΔC in vivo causes melanotic tumors, while in vitro it transactivates a Stat92E-luciferase reporter in the absence of stimulation. These gain-of-function phenotypes require phosphorylation of Y711 and dimer formation with full-length Stat92E. Furthermore, a single point mutation, an R442P substitution in the DNA-binding domain, abolishes Stat92E function. Recombinant Stat92ER442P translocates to the nucleus following activation but fails to function in all assays tested. Interestingly, R442 is conserved in most STATs in higher organisms, suggesting conservation of function. Modeling of Stat92E indicates that R442 may contact the minor groove of DNA via invariant TC bases in the consensus binding element bound by all STAT proteins. We conclude that the N- and C- termini function unexpectedly in negatively regulating Stat92E activity, possibly by decreasing dimer dephosphorylation or increasing stability of DNA interaction, and that Stat92ER442 has a nuclear function by altering dimer:DNA binding. PMID:20501334

  9. The Role of c-KIT in Tumorigenesis: Evaluation in Canine Cutaneous Mast Cell Tumors

    Directory of Open Access Journals (Sweden)

    Joshua D. Webster

    2006-02-01

    Full Text Available The c-KIT proto-oncogene has been implicated in the pathogenesis of several neoplastic diseases, including gastrointestinal stromal tumors and mastocytosis in humans, and mast cell tumors (MCTs in canines. Cutaneous MCTs are common neoplasms in dogs and have a variable biologic behavior. The goal of this study was to define the prognostic significance of c-KIT mutations identified in canine MCTs and the associations between c-KIT mutations, KIT localization, and KIT expression levels. Microdissection and polymerase chain reaction were performed on 60 MCTs to identify c-KIT mutations. Anti-KIT antibodies were used for immunohistochemical evaluation of KIT localization. Forty-two MCTs were included in a tissue microarray, and KIT expression was quantified using immunofluorescence. Canine MCTs with c-KIT mutations were significantly associated with an increased incidence of recurrent disease and death. c-KIT mutations were also significantly associated with aberrant protein localization; however, the level of KIT expression did not correlate with either c-KIT mutations or changes in protein localization. Considering the high prevalence of canine MCTs and the central role of c-KIT in the tumorigenesis of certain tumors, canine MCTs are an excellent model for characterizing the role of c-KIT in neoplastic diseases and is a potential target for novel therapeutic agents in clinical trials.

  10. EXPRESSION OF ANNEXIN I IN TUMORIGENESIS OF ESOPHAGEAL SQUAMOUS CELL CARCINOMA

    Institute of Scientific and Technical Information of China (English)

    吕宁; 薛丽燕; 林冬梅; 谢永强; 温芃; 何祖根

    2004-01-01

    Objective: To detect the expression of annexin I in esophageal squamous cell carcinoma and precursor lesions,and evaluate its effect on the tumorigenesis. Methods: The immunohistochemistry S-P method was used to determine the expression of annexin I in 135 cases of esophageal squamous cell carcinoma, in which precursor lesions were found in some cases, and in the corresponding normal controls. Results: Of 135 cases, 35 (25.9%) were strongly positive, 60 (44.4%) were weakly positive and 40 (29.6%)negative, while in the corresponding normal controls, 129(95.6%) were strongly positive, 6 (6.4%) weakly positive.The expression of annexin I was decreased in esophageal squamous cell carcinoma (P<0.0001), and the degree and rate of the decrease did not show correlation with age,gender, differentiation, and lymph node metastasis (P>0.05).The expression of annexin I was also decreased in the lesions of dysplasia and carcinoma in situ, with 2 (4.3%) strongly positive, 17 (37.0%) weakly positive and 27(58.7%) negative (P<0.0001). Conclusion: Annexin I may be useful in early detection of esophageal squamous cell carcinoma and in evaluation of predisposition for the risk of cancerization of precursor lesions.

  11. Imaging of liver cancer

    Institute of Scientific and Technical Information of China (English)

    Ben Ariff; Claire R Lloyd; Sameer Khan; Mohamed Shariff; Andrew V Thillainayagam; Devinder S Bansi; Shahid A Khan; Simon D Taylor-Robinson; Adrian KP Lim

    2009-01-01

    Improvements in imaging technology allow exploitation of the dual blood supply of the liver to aid in the identi-fication and characterisation of both malignant and benign liver lesions. Imaging techniques available include contrast enhanced ultrasound, computed tomography and magnetic resonance imaging. This review discusses the application of several imaging techniques in the diagnosis and staging of both hepatocellular carcinoma and cholangiocarcinoma and outlines certain characteristics of benign liver lesions. The advantages of each imaging technique are highlighted, while underscoring the potential pitfalls and limitations of each imaging modality.

  12. [Cysts of the liver

    DEFF Research Database (Denmark)

    Hillingso, J.G.; Kirkegaard, P.

    2008-01-01

    Cysts of the liver are discovered in connection with a scope of diseases ranging from simple, infectious, or parasitic to neoplastic cysts. Symptoms, paraclinical, radiological and diagnostic characteristics are described with emphasis on ruling out malignancy. The treatment options from ultrasound...... guided drainage to resections and liver transplantation are discussed. It is concluded that up to 25% of cysts must be treated surgically, because recurrence after percutaneous or laparoscopic treatment is between 5% and 71%, and only resection or liver transplantation are curative Udgivelsesdato: 2008/4/14...

  13. Unique haploinsufficient role of the microRNA-processing molecule Dicer1 in a murine colitis-associated tumorigenesis model.

    Directory of Open Access Journals (Sweden)

    Takeshi Yoshikawa

    Full Text Available A widespread downregulated expression of microRNAs (miRNAs is commonly observed in human cancers. Similarly, deregulated expression of miRNA-processing pathway components, which results in the reduction of global miRNA expression, may also be associated with tumorigenesis. Here, we show that specific ablation of Dicer1 in intestinal epithelial cells accelerates intestinal inflammation-associated tumorigenesis. This effect was apparent only when a single copy of Dicer1 was deleted, but not with complete Dicer1 ablation. DICER expression and subsequent mature miRNA levels were inversely correlated with the number of intact Dicer1 alleles. Because the expression levels of DICER were retained in tumors and its surrounding tissues even after induction of colitis-associated tumors, the effects of Dicer1 deletion were cell-autonomous. Although the expression levels of representative oncogenes and tumor suppressor genes were in most cases inversely correlated with the expression levels of DICER, some genes were not affected by Dicer1 deletion. Thus, deregulating the delicate balance between the expression levels of tumor-promoting and -suppressive genes may be crucial for tumorigenesis in this unique haploinsufficient case.

  14. Distinct functions of epidermal and myeloid-derived VEGF-A in skin tumorigenesis mediated by HPV8.

    Science.gov (United States)

    Ding, Xiaolei; Lucas, Tina; Marcuzzi, Gian P; Pfister, Herbert; Eming, Sabine A

    2015-01-15

    Beta human papillomaviruses (HPV) have been suspected to be carcinogenic in nonmelanoma skin cancers (NMSC), but the basis for potential viral contributions to these cancers is poorly understood. In particular, it is unresolved how HPV-infected keratinocytes escape cell-cycle control and whether their cross-talk with immune cells is critical for tumorigenesis. In nonviral preclinical models, the angiogenic cytokine VEGF-A has been identified as a critical regulator of NMSC. In this study, we dissected the contribution of epidermal versus myeloid cell-derived VEGF-A in HPV-mediated skin cancer by interbreeding an HPV8 transgenic mouse model with a conditional disruption of VEGF-A restricted to either epidermal or myeloid cells. Although only epidermal-derived VEGF-A was essential for initiation of skin tumor development, both spontaneously and UV-light triggered, both epidermal and myeloid cell-derived VEGF-A contributed to regeneration-induced tumorigenesis upon HPV8 overexpression, partly not only through a paracrine effect on endothelial cells, but also most probably through an additional autocrine effect on epidermal cells. Our findings offer new mechanistic insights into distinct functions of epidermal versus myeloid cell-derived VEGF-A during HPV-mediated tumorigenesis, with possible implications for preventing this disease.

  15. O-linked N-acetylglucosamine transferase promotes cervical cancer tumorigenesis through human papillomaviruses E6 and E7 oncogenes.

    Science.gov (United States)

    Kim, Minjun; Kim, Yoon Sook; Kim, Hwajin; Kang, Min Young; Park, Jeongsook; Lee, Dong Hoon; Roh, Gu Seob; Kim, Hyun Joon; Kang, Sang Soo; Cho, Gyeong Jae; Park, Ji Kwon; Cho, Jin Won; Shin, Jeong Kyu; Choi, Wan Sung

    2016-07-12

    O-linked N-acetylglucosamine (O-GlcNAc) transferase (OGT) increases O-GlcNAc modification (O-GlcNAcylation), and transcriptional co-regulator host cell factor 1 (HCF-1) is one of OGT targets. High-risk Human Papillomaviruses (HPVs) encode E6 and E7 oncoproteins, which promote cervical cancer. Here, we tested whether O-GlcNAc modification of HCF-1 affects HPV E6 and E7 expressions and tumorigenesis of cervical cancer. We found that depleting OGT with OGT-specific shRNA significantly decreased levels of E6 and E7 oncoproteins, and cervical cancer tumorigenesis, while OGT overexpression greatly increased levels of E6 and E7 oncoproteins. Notably, OGT overexpression caused dose-dependent increases in the transcriptional activity of E6 and E7, and this activity was decreased when HCF-1 was depleted with HCF-1-specific siRNA. Moreover, OGT depletion reduced proliferation, invasion, and metastasis in cervical cancer cells. Further, high glucose enhanced the interaction between OGT and HCF-1, paralleling increased levels of E6 and E7 in cervical cancer cells. Most importantly, we found that reducing OGT in HeLa cells caused decreased tumor growth in vivo. These findings identify OGT as a novel cellular factor involved in E6 and E7 expressions and cervical cancer tumorigenesis, suggesting that targeting OGT in cervical cancer may have potential therapeutic benefit.

  16. Racing to block tumorigenesis after pRb loss: an innocuous point mutation wins with synthetic lethality.

    Science.gov (United States)

    Bauzon, Frederick; Zhu, Liang

    2010-06-01

    A major goal of tumor suppressor research is to neutralize the tumorigenic effects of their loss. Since loss of pRb does not induce tumorigenesis in many types of cells, natural mechanisms may neutralize the tumorigenic effects of pRb loss in these cells. For susceptible cells, neutralizing the tumorigenic effects of pRb loss could logically be achieved by correcting the deregulated activities of pRb targets to render pRb-deficient cells less abnormal. This line of research has unexpectedly revealed that knocking out the pRb target Skp2 did not render Rb1 deficient cells less abnormal but, rather, induced apoptosis in them, thereby completely blocking tumorigenesis in Rb1+/- mice and after targeted deletion of Rb1 in pituitary intermediate lobe (IL). Skp2 is a substrate-recruiting component of the SCFSkp2 E3 biquitin ligase; one of its substrates is Thr187-phosphorylated p27Kip1. A p27T187A knockin (KI) mutation phenocopied Skp2 knockout (KO) in inducing apoptosis following Rb1 loss. Thus, Skp2 KO or p27T187A KI are synthetic lethal with pRb inactivation. Since homozygous p27T187A KI mutations show no adverse effects in mice, inhibiting p27T187 phosphorylation or p27T187p ubiquitination could be a highly therapeutic and minimally toxic intervention strategy for pRb deficiency-induced tumorigenesis.

  17. Pregnancy-dependent initiation in tumorigenesis of Wistar rat mammary glands by sup 60 Co-irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Inano, Hiroshi; Suzuki, Keiko; Ishii-Ohba, Hiroko; Ikeda, Kiyomi (National Inst. of Radiological Sciences, Chiba (Japan)); Wakabayashi, Katsumi (Gunma Univ., Maebashi (Japan). Hormone Assay Center)

    1991-06-01

    Pregnant Wistar rats received whole body irradiation with 260 cGy {gamma}-rays at days 7, 14 and 20 of pregnancy and then were treated with diethylstilbestrol (DES) for 1 year. The highest incidence (92.9%) for tumorigenesis of mammary glands was observed in the rats irradiated in late pregnancy. Histological examination showed that tumors were classified as fibroadenoma and adenocarcinoma. To determine the reasons for specific induction of mammary tumors by irradiation in late pregnancy, hormone concentrations in serum and estrogen receptors in mammary glands during pregnancy were measured. Concentrations of estradiol, progesterone, 11-deoxycorticosterone and placental lactogen at day 20 were higher than at days 7 and/or 14, but no difference was observed in the concentrations of prolactin and thyroid-stimulating hormone during pregnancy. The estrogen receptor in mammary glands at day 20 was indicated to have the highest affinity and the highest binding capacity during pregnancy. Normal mammary glands at day 20 were suggested to have more abundant epithelial cells in the mammary lobes than those at days 7 and 14. The data suggest that the critical requirements for the initiation of tumorigenesis by {gamma}-rays are dependent upon the differentiated state of mammary glands exposed to various hormones, and that the concentration and persistence of the synthetic estrogen (DES) are necessary for the promotion of tumorigenesis of the irradiated mammary glands. (Author).

  18. Mammary tumorigenesis in APC{sup min/+} mice is enhanced by X-irradiation with a characteristic age dependence

    Energy Technology Data Exchange (ETDEWEB)

    Tatsuhiko, Imaoka; Mayumi, Nishimura; Shizuko, Kakinuma; Yoshiya, Shimada [National Institute of Radiological Sciences, Experimental Radiobiology for Children' s Health Research Group, Research, Center for Radiation Protection (Japan); Mieko, Okamoto [Tokyo Metropolitan Institute of Medical Science (Japan)

    2006-07-01

    The ApcM{sup min/+} (Min) mouse is a genetically predisposed model of both intestinal and mammary tumorigenesis. We investigated age-related changes in the susceptibility of mice (before, during and after puberty) to radiation-induced mammary tumorigenesis using this model. Female Min and wild-type mice having the C57BL/6J background were irradiated with 2 Gy of X-rays at 2, 5, 7 and 10 weeks and sacrificed at 18 weeks of age. Min mice irradiated at 7 to 10 weeks of age (after puberty) developed mammary tumors with squamous metaplasia, whereas their wild-type litter-mates did not. Interestingly, irradiation of Min mice at 2 to 5 weeks (before and during puberty, respectively) did not induce mammary tumors but rather cystic nodules with metaplasia. The mammary tumors exhibited increased nuclear beta-catenin protein and loss of the wild-type Apc allele. Our results show that susceptibility to radiation-induced mammary tumorigenesis increases after puberty in Min mice, suggesting that the tumorigenic effect of ionizing radiation targets the lobular-alveolar progenitor cells, which increase in number with age and are controlled by beta-catenin signaling. (author)

  19. Pubertal and adult windows of susceptibility to a high animal fat diet in Trp53-null mammary tumorigenesis.

    Science.gov (United States)

    Zhu, Yirong; Aupperlee, Mark D; Zhao, Yong; Tan, Ying Siow; Kirk, Erin L; Sun, Xuezheng; Troester, Melissa A; Schwartz, Richard C; Haslam, Sandra Z

    2016-12-13

    Premenopausal breast cancer is associated with increased animal fat consumption among normal weight, but not overweight women (Farvid et al., 2014). Our previous findings in obesity-resistant BALB/c mice similarly showed promotion of carcinogen-induced mammary tumorigenesis by a diet high in saturated animal fat (HFD). This effect was specific to pubertal versus adult HFD. This study identifies the effects of HFD during puberty versus adulthood in Trp53-null transplant BALB/c mice and investigates its mechanism of enhancing tumorigenesis. Either pubertal or adult HFD is sufficient to increase incidence of Trp53-null mammary tumors. Puberty-restricted HFD exposure promoted tumor cell proliferation, increased angiogenesis, and increased recruitment of total and M2 macrophages in epithelial tumors. Adult-restricted exposure to HFD similarly increased proliferation, angiogenesis, recruitment of total and M2 macrophages, and additionally reduced apoptosis. Adult HFD also increased incidence of spindle cell carcinomas resembling claudin-low breast cancer, and thus adult HFD in the Trp53-null transplantation system may be a useful model for human claudin low breast cancer. Importantly, these results on Trp53-null and our prior studies on DMBA-induced mammary tumorigenesis demonstrate a pubertal window of susceptibility to the promotional effects of HFD, indicating the potential of early life dietary intervention to reduce breast cancer risk.

  20. Butylated Hydroxyanisole Blocks the Occurrence of Tumor Associated Macrophages in Tobacco Smoke Carcinogen-Induced Lung Tumorigenesis

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yan; Choksi, Swati; Liu, Zheng-Gang, E-mail: zgliu@helix.nih.gov [Cell and Cancer Biology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States)

    2013-12-04

    Tumor-associated macrophages (TAMs) promote tumorigenesis because of their proangiogenic and immune-suppressive functions. Here, we report that butylated hydroxyanisole (BHA) blocks occurrence of tumor associated macrophages (TAMs) in tobacco smoke carcinogen-induced lung tumorigenesis. Continuous administration of butylated hydroxyanisole (BHA), a ROS inhibitor, before or after NNK treatment significantly blocked tumor development, although less effectively when BHA is administered after NNK treatment. Strikingly, BHA abolished the occurrence of F4/80{sup +} macrophages with similar efficiency no matter whether it was administered before or after NNK treatment. Detection of cells from bronchioalveolar lavage fluid (BALF) confirmed that BHA markedly inhibited the accumulation of macrophages while slightly reducing the number of lymphocytes that were induced by NNK. Immunohistological staining showed that BHA specifically abolished the occurrence of CD206{sup +} TAMs when it was administered before or after NNK treatment. Western blot analysis of TAMs markers, arginase I and Ym-1, showed that BHA blocked NNK-induced TAMs accumulation. Our study clearly demonstrated that inhibiting the occurrence of TAMs by BHA contributes to the inhibition of tobacco smoke carcinogen-induced tumorigenesis, suggesting ROS inhibitors may serve as a therapeutic target for treating smoke-induced lung cancer.

  1. Circadian disruption induced by light-at-night accelerates aging and promotes tumorigenesis in young but not in old rats

    Science.gov (United States)

    Vinogradova, Irina A.; Anisimov, Vladimir N.; Bukalev, Andrey V.; Ilyukha, Viktor A.; Khizhkin, Evgeniy A.; Lotosh, Tatiana A.; Semenchenko, Anna V.; Zabezhinski, Mark A.

    2010-01-01

    We evaluated the effect of exposure to constant light started at the age of 1 month and at the age of 14 months on the survival, life span, tumorigenesis and age-related dynamics of antioxidant enzymes activity in various organs in comparison to the rats maintained at the standard (12:12 light/dark) light/dark regimen. We found that exposure to constant light started at the age of 1 month accelerated spontaneous tumorigenesis and shortened life span both in male and female rats as compared to the standard regimen. At the same time, the exposure to constant light started at the age of 14 months failed to influence survival of male and female rats. While delaying tumors in males, constant light accelerated tumors in females. We conclude that circadian disruption induced by light-at-night started at the age of 1 month accelerates aging and promotes tumorigenesis in rats, however failed affect survival when started at the age of 14 months. PMID:20354269

  2. Liver Transplant: Nutrition

    Science.gov (United States)

    ... include poultry, eggs, fish, tofu, and soy protein. Low Sodium -- Symptoms of advanced liver disease include excess fluid ... it is very important to stick to a low sodium diet, especially when these symptoms start to develop. ...

  3. American Liver Foundation

    Science.gov (United States)

    ... organ, eye and tissue donation. Learn more about organ donation . Locate a Specialist Find a medical professional nearby ... Help us spread the word about liver disease, organ donation, and the ALF- amplifying the message through social ...

  4. [Nutrition and liver failure].

    Science.gov (United States)

    Plauth, M

    2013-06-01

    In the critically ill liver patient, nutrition support is not very different from that given for other illnesses. In hyperacute liver failure, nutrition support is of less importance than in the other subtypes of acute liver failure that take a more protracted course. Nasoenteral tube feeding using a polymeric standard formula should be the first-line approach, while parenteral nutrition giving glucose, fat, amino acids, vitamins, and trace elements is initiated when enteral nutrition is insufficient or impracticable. In chronic liver disease, notably cirrhosis, there is frequently protein malnutrition indicating a poor prognosis and requiring immediate initiation of nutrition support. Enteral nutrition ensuring an adequate provision of energy and protein should be preferred. Particular care should be taken to avoid refeeding syndrome and to treat vitamin and trace element deficiency.

  5. 492 Review Liver

    African Journals Online (AJOL)

    Marinda

    2009-11-26

    Nov 26, 2009 ... to define clinical and blood test predictors for major bleeding during liver ... A recent meta-analysis of randomised controlled trials comparing these devices to .... These are either fibrin sealants that mimic coagulation, agents.

  6. [Wilson disease: liver form].

    Science.gov (United States)

    Guerra Montero, Luis; Ortega Álvarez, Félix; Sumire Umeres, Julia; Cok García, Jaime

    2015-01-01

    Wilson disease (WD) is a disorder of copper metabolism that is inherited as an autosomal recessive, which produces toxic copper accumulation mainly in the liver and brain, in general has two ways presentation, liver at early ages and neurological in later ages. We present the case of a female patient of 21 years diagnosed of WD in liver cirrhosis that started with an edematous ascites without any neurological symptoms despite the age. Their laboratory studies showed decrease in serum ceruloplasmin and high cupruria within 24 hours of the disease , characteristic data of WD. Although WD is not a common disease should be suspected in all chronic liver disease of unknown etiology with negative viral markers and autoimmunity with or without neurological manifestations as soon as posible and starting treatment with copper chelating mainly leads to a substantial improvement the prognosis of these patients.

  7. Pediatric liver transplantation

    Institute of Scientific and Technical Information of China (English)

    Marco Spada; Silvia Riva; Giuseppe Maggiore; Davide Cintorino; Bruno Gridelli

    2009-01-01

    In previous decades, pediatric liver transplantation has become a state-of-the-art operation with excellent success and limited mortality. Graft and patient survival have continued to improve as a result of improvements in medical, surgical and anesthetic management, organ availability, immunosuppression, and identification and treatment of postoperative complications. The utilization of split-liver grafts and living-related donors has provided more organs for pediatric patients. Newer immunosuppression regimens, including induction therapy, have had a significant impact on graft and patient survival. Future developments of pediatric liver transplantation will deal with long-term followup, with prevention of immunosuppression-related complications and promotion of as normal growth as possible. This review describes the state-of-the-art in pediatric liver transplantation.

  8. [Diabetes in liver cirrhosis].

    Science.gov (United States)

    García-Compeán, Diego; Jáquez-Quintana, Joel O; González-González, José A; Lavalle-González, Fernando J; Villarreal-Pérez, Jesús Z; Maldonado-Garza, Hector J

    2013-01-01

    The prevalence of overt diabetes mellitus (DM) in liver cirrhosis is about 30%. However, DM or impaired glucose tolerance can be observed in 90% after an oral glucose tolerance test in patients with normal fasting plasma glucose. Type 2 DM may produce cirrhosis, whereas DM may be a complication of cirrhosis. The latter is known as «hepatogenous diabetes». Overt and subclinical DM is associated with liver complications and death in cirrhotic patients. Treating diabetes is difficult in cirrhotic patients because of the metabolic impairments due to liver disease and because the most appropriate pharmacologic treatment has not been defined. It is also unknown if glycemic control with hypoglycemic agents has any impact on the course of the liver disease. Copyright © 2013 Elsevier España, S.L. y AEEH y AEG. All rights reserved.

  9. Fusobacterium Liver Abscess

    Directory of Open Access Journals (Sweden)

    Ben D. Buelow

    2013-11-01

    Full Text Available Fusobacterium is well characterized as an oropharyngeal pathogen that may induce a septic thrombophlebitis by direct extension of abscess into an adjacent neck vessel (Lemierre's syndrome; its potential for visceral abscess formation, however, remains under-recognized. A 65-year-old man with a recent history of multiple rim-enhancing liver lesions presented to the emergency room with fever and abdominal pain. Based on interval increase in the size of the lesions, abscess was suspected. A liver biopsy was performed, and although no organism could be identified on routine microscopy, Warthin-Starry stain revealed Gram-negative bacilli consistent with an anaerobic Fusobacterium species as the underlying etiology of liver abscess formation. Subsequent anaerobic culture results confirmed the diagnosis. This case highlights the importance of consideration for Fusobacterium infection in the setting of liver abscess if anaerobic organisms have not yet been excluded on initial culture evaluation.

  10. Autoimmune liver diseases

    Institute of Scientific and Technical Information of China (English)

    Pietro Invernizzi; Ian R Mackay

    2008-01-01

    The liver was one of the earliest recognized sites among autoimmune diseases yet autoimmune hepatitis,primary biliary cirrhosis,primary sclerosing cholangitis,and their overlap forms,are still problematic in diagnosis and causation.The contributions herein comprise 'pairs of articles' on clinical characteristics,and concepts of etiopathogenesis,for each of the above diseases,together with childhood autoimmune liver disease,overlaps,interpretations of diagnostic serology,and liver transplantation.This issue is timely,since we are witnessing an ever increasing applicability of immunology to a wide variety of chronic diseases,hepatic and non-hepatic,in both developed and developing countries.The 11 invited expert review articles capture the changing features over recent years of the autoimmune liver diseases,the underlying immunomolecular mechanisms of development,the potent albeit still unexplained genetic influences,the expanding repertoire of immunoserological diagnostic markers,and the increasingly effective therapeutic possibilities.

  11. Mice with humanized liver endothelium

    NARCIS (Netherlands)

    el Filali, E.

    2014-01-01

    The only curative treatment option for a large proportion of patients suffering from a liver disorder is liver transplantation. The use of ex vivo genetically modified autologous liver cells instead of whole liver transplantation could overcome the problem of donor scarcity. Even though clinical

  12. Antioxidant supplements for liver diseases

    DEFF Research Database (Denmark)

    Bjelakovic, Goran; Gluud, Lise Lotte; Nikolova, Dimitrinka

    2011-01-01

    Several liver diseases have been associated with oxidative stress. Accordingly, antioxidants have been suggested as potential therapeutics for various liver diseases. The evidence supporting these suggestions is equivocal.......Several liver diseases have been associated with oxidative stress. Accordingly, antioxidants have been suggested as potential therapeutics for various liver diseases. The evidence supporting these suggestions is equivocal....

  13. Mice with humanized liver endothelium

    NARCIS (Netherlands)

    el Filali, E.

    2014-01-01

    The only curative treatment option for a large proportion of patients suffering from a liver disorder is liver transplantation. The use of ex vivo genetically modified autologous liver cells instead of whole liver transplantation could overcome the problem of donor scarcity. Even though clinical tri

  14. Acute liver failure

    DEFF Research Database (Denmark)

    Larsen, Fin Stolze; Bjerring, Peter Nissen

    2011-01-01

    Acute liver failure (ALF) results in a multitude of serious complications that often lead to multi-organ failure. This brief review focuses on the pathophysiological processes in ALF and how to manage these.......Acute liver failure (ALF) results in a multitude of serious complications that often lead to multi-organ failure. This brief review focuses on the pathophysiological processes in ALF and how to manage these....

  15. Liver and Biliary System

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    2008546 Effects of gene-transfected bone marrow-derived liver stem cell transplantation on accumulation of extracellular matrix in rats with liver fibrosis.SUN Chao(孙超),et al.Dept Gastroenterol,Xinhua Hosp,Shanghai Jiaotong Univ,Shanghai 200092.Natl Med J China 2008;88(38):2685-2689. Objective To explore the effects of urokinase-type plasminogen activator(uPA)gene modified bone marrow-derived stem cell(BDLSC)

  16. LIVER TRANSPLANTATION AND HBV INFECTION

    Directory of Open Access Journals (Sweden)

    O. I. Andreytseva

    2009-01-01

    Full Text Available The paper describes the modern approaches in treatment of hepatitis B virus (HBV-infected patients who underwent liver transplantation. The patients with HBV liver cirrhosis and waiting for orthotopic liver transplantation (OLT have to receive long-term therapy with nucleos(tide analogs right up to liver transplantation. The paper discuss the different schemes of prophylaxis of recurrent HBV infection during post-transplantation and specific treatment of HBV infection after liver transplantation as well as possibilities of orthotopic liver transplantation for patients with liver cancer. 

  17. Split liver transplantation.

    Science.gov (United States)

    Yersiz, H; Cameron, A M; Carmody, I; Zimmerman, M A; Kelly, B S; Ghobrial, R M; Farmer, D G; Busuttil, R W

    2006-03-01

    Seventy-five thousand Americans develop organ failure each year. Fifteen percent of those on the list for transplantation die while waiting. Several possible mechanisms to expand the organ pool are being pursued including the use of extended criteria donors, living donation, and split deceased donor transplants. Cadaveric organ splitting results from improved understanding of the surgical anatomy of the liver derived from Couinaud. Early efforts focused on reduced-liver transplantation (RLT) reported by both Bismuth and Broelsch in the mid-1980s. These techniques were soon modified to create both a left lateral segment graft appropriate for a pediatric recipient and a right trisegment for an appropriately sized adult. Techniques of split liver transplantation (SLT) were also modified to create living donor liver transplantation. Pichlmayr and Bismuth reported successful split liver transplantation in 1989 and Emond reported a larger series of nine split procedures in 1990. Broelsch and Busuttil described a technical modification in which the split was performed in situ at the donor institution with surgical division completed in the heart beating cadaveric donor. In situ splitting reduces cold ischemia, simplifies identification of biliary and vascular structures, and reduces reperfusion hemorrhage. However, in situ splits require specialized skills, prolonged operating room time, and increased logistical coordination at the donor institution. At UCLA over 120 in situ splits have been performed and this technique is the default when an optimal donor is available. Split liver transplantation now accounts for 10% of adult transplantations at UCLA and 40% of pediatric transplantations.

  18. Liver disease and malnutrition.

    Science.gov (United States)

    Purnak, Tugrul; Yilmaz, Yusuf

    2013-08-01

    Patients with hepatic disorders are exceptionally vulnerable to developing malnutrition because of the key role played by the liver in regulating the nutritional state and the energy balance. Moreover, the presence of chronic liver disorders could reduce the appetite and thus influence the nutrient intake. Poor nutritional status has been shown in various patient groups with hepatic disorders, and particularly in patients with alcoholic cirrhosis who are at high nutritional risk. It is well established that malnourished patients with liver diseases generally have a higher risk of developing adverse clinical outcomes and increased healthcare costs. Nutrition screening with the Subjective Global Assessment and anthropometric measurements are an important first step in the early identification of malnutrition and initiates the whole nutrition care process. It is therefore important for appropriate nutrition policies and protocols to be implemented so that all patients with chronic liver diseases are monitored closely from a nutritional standpoint. Early and evidence-based nutritional interventions are eagerly needed to minimize the nutritional decline associated with chronic liver disorders and ultimately improve the prognosis of such patients. This review includes a comprehensive analysis of methods to identify malnutrition in patients with chronic liver diseases as well as the extent and impact of the malnutrition problem in selected patient populations.

  19. Excellent survival after liver transplantation for isolated polycystic liver disease : an European Liver Transplant Registry study

    NARCIS (Netherlands)

    van Keimpema, Loes; Nevens, Frederik; Adam, Rene; Porte, Robert J.; Fikatas, Panagiotis; Becker, Thomas; Kirkegaard, Preben; Metselaar, Herold J.; Drenth, Joost P. H.

    2011-01-01

    Patients with end-stage isolated polycystic liver disease (PCLD) suffer from incapacitating symptoms because of very large liver volumes. Liver transplantation (LT) is the only curative option. This study assesses the feasibility of LT in PCLD. We used the European Liver Transplant Registry (ELTR) d

  20. Excellent survival after liver transplantation for isolated polycystic liver disease: an European Liver Transplant Registry study

    DEFF Research Database (Denmark)

    van Keimpema, Loes; Nevens, Frederik; Adam, René

    2011-01-01

    Patients with end-stage isolated polycystic liver disease (PCLD) suffer from incapacitating symptoms because of very large liver volumes. Liver transplantation (LT) is the only curative option. This study assesses the feasibility of LT in PCLD. We used the European Liver Transplant Registry (ELTR...

  1. Excellent survival after liver transplantation for isolated polycystic liver disease : an European Liver Transplant Registry study

    NARCIS (Netherlands)

    van Keimpema, Loes; Nevens, Frederik; Adam, Rene; Porte, Robert J.; Fikatas, Panagiotis; Becker, Thomas; Kirkegaard, Preben; Metselaar, Herold J.; Drenth, Joost P. H.

    2011-01-01

    Patients with end-stage isolated polycystic liver disease (PCLD) suffer from incapacitating symptoms because of very large liver volumes. Liver transplantation (LT) is the only curative option. This study assesses the feasibility of LT in PCLD. We used the European Liver Transplant Registry (ELTR)

  2. HYPERVASCULAR LIVER LESIONS IN RADIOLOGICALLY NORMAL LIVER.

    Science.gov (United States)

    Amico, Enio Campos; Alves, José Roberto; Souza, Dyego Leandro Bezerra de; Salviano, Fellipe Alexandre Macena; João, Samir Assi; Liguori, Adriano de Araújo Lima

    2017-01-01

    The hypervascular liver lesions represent a diagnostic challenge. To identify risk factors for cancer in patients with non-hemangiomatous hypervascular hepatic lesions in radiologically normal liver. This prospective study included patients with hypervascular liver lesions in radiologically normal liver. The diagnosis was made by biopsy or was presumed on the basis of radiologic stability in follow-up period of one year. Cirrhosis or patients with typical imaging characteristics of haemangioma were excluded. Eighty-eight patients were included. The average age was 42.4. The lesions were unique and were between 2-5 cm in size in most cases. Liver biopsy was performed in approximately 1/3 of cases. The lesions were benign or most likely benign in 81.8%, while cancer was diagnosed in 12.5% of cases. Univariate analysis showed that age >45 years (p3 nodules (p=0.003) and elevated alkaline phosphatase (p=0.013) were significant risk factors for cancer. It is safe to observe hypervascular liver lesions in normal liver in patients up to 45 years, normal alanine aminotransaminase, up to three nodules and no personal history of cancer. Lesion biopsies are safe in patients with atypical lesions and define the treatment to be established for most of these patients. As lesões hepáticas hipervasculares representam um desafio diagnóstico. Identificar fatores de risco para câncer em pacientes portadores de lesão hepática hipervascular não-hemangiomatosa em fígado radiologicamente normal. Estudo prospectivo que incluiu pacientes com lesões hepáticas hipervasculares em que o diagnóstico final foi obtido por exame anatomopatológico ou, presumido a partir de seguimento mínimo de um ano. Diagnóstico prévio de cirrose ou radiológico de hemangioma foram considerados critérios de exclusão. Oitenta e oito pacientes foram incluídos. A relação mulher/homem foi de 5,3/1. A idade média foi de 42,4 anos. Na maior parte das vezes as lesões hepáticas foram únicas e com

  3. SIRT1 and c-Myc Promote Liver Tumor Cell Survival and Predict Poor Survival of Human Hepatocellular Carcinomas

    Science.gov (United States)

    Jang, Kyu Yun; Noh, Sang Jae; Lehwald, Nadja; Tao, Guo-Zhong; Bellovin, David I.; Park, Ho Sung; Moon, Woo Sung; Felsher, Dean W.; Sylvester, Karl G.

    2012-01-01

    The increased expression of SIRT1 has recently been identified in numerous human tumors and a possible correlation with c-Myc oncogene has been proposed. However, it remains unclear whether SIRT1 functions as an oncogene or tumor suppressor. We sought to elucidate the role of SIRT1 in liver cancer under the influence of c-Myc and to determine the prognostic significance of SIRT1 and c-Myc expression in human hepatocellular carcinoma. The effect of either over-expression or knock down of SIRT1 on cell proliferation and survival was evaluated in both mouse and human liver cancer cells. Nicotinamide, an inhibitor of SIRT1, was also evaluated for its effects on liver tumorigenesis. The prognostic significance of the immunohistochemical detection of SIRT1 and c-Myc was evaluated in 154 hepatocellular carcinoma patients. SIRT1 and c-Myc regulate each other via a positive feedback loop and act synergistically to promote hepatocellular proliferation in both mice and human liver tumor cells. Tumor growth was significantly inhibited by nicotinamide in vivo and in vitro. In human hepatocellular carcinoma, SIRT1 expression positively correlated with c-Myc, Ki67 and p53 expression, as well as high á-fetoprotein level. Moreover, the expression of SIRT1, c-Myc and p53 were independent prognostic indicators of hepatocellular carcinoma. In conclusion, this study demonstrates that SIRT1 expression supports liver tumorigenesis and is closely correlated with oncogenic c-MYC expression. In addition, both SIRT1 and c-Myc may be useful prognostic indicators of hepatocellular carcinoma and SIRT1 targeted therapy may be beneficial in the treatment of hepatocellular carcinoma. PMID:23024800

  4. Type I Insulin-like Growth Factor Receptor Induces Pulmonary Tumorigenesis

    Directory of Open Access Journals (Sweden)

    Nicolle M. Linnerth

    2009-07-01

    Full Text Available Despite the type I insulin-like growth factor receptor (IGF-IR being highly expressed in more than 80% of human lung tumors, a transgenic model of IGF-IR overexpression in the lung has not been created. We produced two novel transgenic mouse models in which IGF-IR is overexpressed in either lung type II alveolar cells (surfactant protein C [SPC]-IGFIR or Clara cells (CCSP-IGFIR in a doxycycline-inducible manner. Overexpression of IGF-IR in either cell type caused multifocal adenomatous alveolar hyperplasia with papillary and solid adenomas. These tumors expressed thyroid transcription factor 1 and Kruppel-like factor 5 in most tumor cells. Similar to our previous work with lung tumors that developed in the mouse mammary tumor virus-IGF-II transgenic mice, the lung tumors that develop in the SPC-IGFIR and CCSP-IGFIR transgenic mice expressed high levels of the cyclic adenosine monophosphate response element binding protein that was localized primarily to the nucleus. Although elevated IGF-IR expression can initiate lung tumor development, tumors can become independent of IGF-IR signaling as IGF-IR down-regulation in established tumors produced tumor regression in some, but not all, of the tumors. These findings implicate IGF-IR as an important initiator of lung tumorigenesis and suggest that the SPC-IGFIR and CCSP-IGFIR transgenic mice can be used to further our understanding of human lung cancer and the role IGF-IR plays in this disease.

  5. PTEN coding product:a new marker for tumorigenesis and progession of endometrial carcinoma

    Institute of Scientific and Technical Information of China (English)

    Gao Qinglei; Li Jing; Xing Hui; Lu Yunping; Zhou Jianfeng; Ma Ding

    2008-01-01

    Objective :To investigate the expression of PTEN in carcinogenesis and development of endometrial carcinoma.Methods: The expression of PTEN was detected by reverse transcription-polymerase chain reaction(RT-PCR) methods from 24 cases with endometrial carcinoma,10 cases with endometrial atypical hyperplasia,I0 eases with endometrial hyperplasia and I0 cases with normal endometrium and by SP immunohistochemical methods from 73 cases with endometrial carcinoma,25 cases with endometrial atypical hyperplasia,71 cases with endometrial hyperplasia and 31 cases with normal endometrium.Results:PTEN expression of both RNA and protein in patients with endometrial carcinoma and endometrial atypical hyperplasia was significantly lower than that of patients with endometrial hyperplasia and normal endometriurn.mRNA relative value was 0.35±0.13,0.46±0.11,2.32±0.32,2.45±0.51,respectively.Loss of PTEN expression rates were 66.67% (38/57) ,76.00% ( 19/25 ) ,5.63% (4/71 ) ,0 (0/31 ),repeetively.The results were also compared with clinical parameters.Loss of PTEN expression in patients with endometrial carcinoma was significantly related to histological classification ( P < 0.0001 ) and differentiation ( P < 0.05 ).It was not related to depth of myometrium invasion and clinical stage( P >0.05 ).Conclusion:Loss of PTEN expression is an early event in endometrial tumorigenesis.Detection of PTEN protein may be a diagnostic biomarker for endometrial precancers and adenocareinoma.

  6. Polycomb Repressor Complex 1 Member, BMI1 Contributes to Urothelial Tumorigenesis through p16-Independent Mechanisms

    Directory of Open Access Journals (Sweden)

    Lia E. De Faveri

    2015-10-01

    Full Text Available Urothelial carcinoma (UC causes significant morbidity and remains the most expensive cancer to treat because of the need for repeated resections and lifelong monitoring for patients with non–muscle-invasive bladder cancer (NMIBC. Novel therapeutics and stratification approaches are needed to improve the outlook for both NMIBC and muscle-invasive bladder cancer. We investigated the expression and effects of B Lymphoma Mo-MLV Insertion Region 1 (BMI1 in UC. BMI1 was found to be overexpressed in most UC cell lines and primary tumors by quantitative real-time polymerase chain reaction and immunohistochemistry. In contrast to some previous reports, no association with tumor stage or grade was observed in two independent tumor panels. Furthermore, upregulation of BMI1 was detected in premalignant bladder lesions, suggesting a role early in tumorigenesis. BMI1 is not located within a common region of genomic amplification in UC. The CDKN2A locus (which encodes the p16 tumor suppressor gene is a transcriptional target of BMI1 in some cellular contexts. In UC cell lines and primary tissues, no correlation between BMI1 and p16 expression was observed. Retroviral-mediated overexpression of BMI1 immortalized normal human urothelial cells (NHUC in vitro and was associated with induction of telomerase activity, bypass of senescence, and repression of differentiation. The effects of BMI1 on gene expression were identified by expression microarray analysis of NHUC-BMI1. Metacore analysis of the gene expression profile implicated downstream effects of BMI1 on α4/β1 integrin-mediated adhesion, cytoskeleton remodeling, and CREB1-mediated transcription.

  7. Expression profiling of CEACAM6 associated with the tumorigenesis and progression in gastric adenocarcinoma.

    Science.gov (United States)

    Deng, X; Liu, P; Zhao, Y; Wang, Q

    2014-09-26

    Carcinoembryonic antigen-related cellular adhesion molecule 6 (CEACAM6) is a member of the immunoglobulin superfamily and has been recently reported to affect the neoplastic, metastatic, and invasive ability of malignant cells by regulating intracellular signaling pathways during tumorigenesis and progression. We investigated the expression and amplification of CEACAM6 in relation to the clinicopathological and biological significance of gastric adenocarcinoma. Expression of CEACAM6 mRNA in 75 primary gastric adenocarcinom and 20 adjacent tissues compared to normal gastric mucosas were explored using real-time quantitative-polymerase chain reaction. Immunohistochemical assays were conducted to evaluate the expression and tissue distribution of CEACAM6 protein. Overexpression of CEACAM6 mRNA in both gastric adenocarcinoma (2.513 ± 0.869) and adjacent tissues (1.171 ± 0.428) was significantly higher than the relative expressions in non-neoplastic specimens (0.594 ± 0.513) (P < 0.01). CEACAM6 protein was present in 52 (69.33%) gastric adenocarcinomas, but not in normal gastric tissues. Adenocarcinomas with elevated CEACAM6 expression were significantly associated with lymph node metastases and advanced stages. There were no relationships between CEACAM6 expression and tumor size, histological differentiation, or different subtypes, respectively. Moreover, higher expression of CEACAM6 was found to be correlated with short postoperative survival time of patients with gastric cancer. Amplification and upregulation of CEACAM6 expression was observed in human gastric adenocarcinomas, which may be correlated with the generation or transformation of malignant cells, tumor aggressive progression, and clinical outcome. CEACAM6 may be a valuable biomarker screening for gastric tumor and novel predictor for patients in advanced stages of gastric cancer.

  8. A targeted constitutive mutation in the APC tumor suppressor gene underlies mammary but not intestinal tumorigenesis.

    Directory of Open Access Journals (Sweden)

    Claudia Gaspar

    2009-07-01

    Full Text Available Germline mutations in the adenomatous polyposis coli (APC gene are responsible for familial adenomatous polyposis (FAP, an autosomal dominant hereditary predisposition to the development of multiple colorectal adenomas and of a broad spectrum of extra-intestinal tumors. Moreover, somatic APC mutations play a rate-limiting and initiating role in the majority of sporadic colorectal cancers. Notwithstanding its multifunctional nature, the main tumor suppressing activity of the APC gene resides in its ability to regulate Wnt/beta-catenin signaling. Notably, genotype-phenotype correlations have been established at the APC gene between the length and stability of the truncated proteins encoded by different mutant alleles, the corresponding levels of Wnt/beta-catenin signaling activity they encode for, and the incidence and distribution of intestinal and extra-intestinal tumors. Here, we report a novel mouse model, Apc1572T, obtained by targeting a truncated mutation at codon 1572 in the endogenous Apc gene. This hypomorphic mutant allele results in intermediate levels of Wnt/beta-catenin signaling activation when compared with other Apc mutations associated with multifocal intestinal tumors. Notwithstanding the constitutive nature of the mutation, Apc(+/1572T mice have no predisposition to intestinal cancer but develop multifocal mammary adenocarcinomas and subsequent pulmonary metastases in both genders. The histology of the Apc1572T primary mammary tumours is highly heterogeneous with luminal, myoepithelial, and squamous lineages and is reminiscent of metaplastic carcinoma of the breast in humans. The striking phenotype of Apc(+/1572T mice suggests that specific dosages of Wnt/beta-catenin signaling activity differentially affect tissue homeostasis and initiate tumorigenesis in an organ-specific fashion.

  9. miR-935 suppresses gastric signet ring cell carcinoma tumorigenesis by targeting Notch1 expression

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Chao [Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, 100730 (China); Yu, Jianchun, E-mail: yu_jchpumch@163.com [Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, 100730 (China); Kang, Weiming [Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, 100730 (China); Liu, Yuqin [Cell Culture Center, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100005 (China); Ma, Zhiqiang; Zhou, Li [Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, 100730 (China)

    2016-01-29

    Gastric signet ring cell carcinoma (GSRCC) is a unique pathological type of gastric carcinoma that is extremely invasive and has a poor prognosis. Expression of microRNAs (miRNAs) has been closely linked to the carcinogenesis of gastric cancer and has been considered as a powerful prognostic marker. The function of miR-935 has never been reported in cancer before. We found, using microRNA array, that expression of miR-935 in GSRCC cell lines is lower than in non-GSRCC cell lines, and enhanced expression of miR-935 in GSRCC cell-lines inhibit cell proliferation, migration and invasion. We also identified Notch1 as a direct target of miR-935. Knockdown of Notch1 reduced proliferation, migration/invasion of GSRCC cells, and overexpression Notch1's activated form (Notch intracellular domain) could rescue miR-935's tumor suppressive effect on GSRCC. Expression of miR-935 was lower in gastric carcinoma tissue than in paired normal tissue samples, and lower in GSRCC than in non-GSRCC. Our results demonstrate the inverse correlation between the expression of miR-935 and Notch1 in gastric tissues. We conclude that miR-935 inhibits gastric carcinoma cell proliferation, migration and invasion by targeting Notch1, suggesting potential applications of the miR-935-Notch1 pathway in gastric cancer clinical diagnosis and therapeutics, especially in gastric signet ring cell carcinoma. - Highlights: • The expression of miR-935 is lower in GC tissue than in paired normal tissue. • The expression of miR-935 is lower in GSRCC tissue than in non-GSRCC. • Enhanced expression of miR-935 suppresses tumorigenesis of GSRCC. • Notch1 is a direct target of miR-935.

  10. Loss of p53 Induces Tumorigenesis in p21-Deficient Mesenchymal Stem Cells

    Directory of Open Access Journals (Sweden)

    Rene Rodriguez

    2009-04-01

    Full Text Available There is growing evidence about the role of mesenchymal stem cells (MSCs as cancer stem cells in many sarcomas. Nevertheless, little is still known about the cellular and molecular mechanisms underlying MSCs transformation. We aimed at investigating the role of p53 and p21, two important regulators of the cell cycle progression and apoptosis normally involved in protection against tumorigenesis. Mesenchymal stem cells from wild-type, p21-/-p53+/+, and p21-/-p53+/- mice were cultured in vitro and analyzed for the appearance of tumoral transformation properties after low, medium, and high number of passages both in vitro and in vivo. Wild-type or p21-/-p53+/+ MSCs did not show any sign of tumoral transformation. Indeed, after short-term in vitro culture, wild-type MSCs became senescent, and p21-/-p53+/+ MSCs showed an elevated spontaneous apoptosis rate. Conversely, MSCs carrying a mutation in one allele of the p53 gene (p21-/-p53+/- MSCs completely lost p53 expression after in vitro long-term culture. Loss of p53 was accompanied by a significant increase in the growth rate, gain of karyotypic instability, loss of p16 expression, and lack of senescence response. Finally, these cells were able to form fibrosarcomas partially differentiated into different mesenchymal lineages when injected in immunodeficient mice both after subcutaneous and intrafemoral injection. These findings show that MSCs are very sensitive to mutations in genes involved in cell cycle control and that these deficiencies can be at the origin of some mesodermic tumors.

  11. A protein knockdown strategy to study the function of β-catenin in tumorigenesis

    Directory of Open Access Journals (Sweden)

    Zhou Pengbo

    2003-09-01

    Full Text Available Abstract Background The Wnt signaling pathway plays critical roles in cell proliferation and cell fate determination at many stages of development. A critical downstream target of Wnt signaling is the cytosolic β-catenin, which is stabilized upon Wnt activation and promotes transcription of a variety of target genes including c-myc and cyclin D. Aberrant Wnt signaling, which results from mutations of either β-catenin or adenomatous polyposis coli (APC, renders β-catenin resistant to degradation, and has been associated with multiple types of human cancers. Results A protein knockdown strategy was designed to reduce the cytosolic β-catenin levels through accelerating its turnover rate. By engineering a chimeric protein with the β-catenin binding domain of E-cadherin fused to βTrCP ubiquitin-protein ligase, the stable β-catenin mutant was recruited to the cellular SCF (Skp1, Cullin 1, and F-box-containing substrate receptor ubiquitination machinery for ubiquitination and degradation. The DLD1 colon cancer cells express wild type β-catenin at abnormally high levels due to loss of APC. Remarkably, conditional expression of βTrCP-E-cadherin under the control of a tetracycline-repressive promoter in DLD1 cells selectively knocked down the cytosolic, but not membrane-associated subpopulation of β-catenin. As a result, DLD1 cells were impaired in their growth and clonogenic ability in vitro, and lost their tumorigenic potential in nude mice. Conclusion We have designed a novel approach to induce degradation of stabilized/mutated β-catenin. Our results suggest that a high concentration of cytoplasmic β-catenin is critical for the growth of colorectal tumor cells. The protein knockdown strategy can be utilized not only as a novel method to dissect the role of oncoproteins in tumorigenesis, but also as a unique tool to delineate the function of a subpopulation of proteins localized to a specific subcellular compartment.

  12. In vivo fluorescence imaging reveals the promotion of mammary tumorigenesis by mesenchymal stromal cells.

    Directory of Open Access Journals (Sweden)

    Chien-Chih Ke

    Full Text Available Mesenchymal stromal cells (MSCs are multipotent adult stem cells which are recruited to the tumor microenvironment (TME and influence tumor progression through multiple mechanisms. In this study, we examined the effects of MSCs on the tunmorigenic capacity of 4T1 murine mammary cancer cells. It was found that MSC-conditioned medium increased the proliferation, migration, and efficiency of mammosphere formation of 4T1 cells in vitro. When co-injected with MSCs into the mouse mammary fat pad, 4T1 cells showed enhanced tumor growth and generated increased spontaneous lung metastasis. Using in vivo fluorescence color-coded imaging, the interaction between GFP-expressing MSCs and RFP-expressing 4T1 cells was monitored. As few as five 4T1 cells could give rise to tumor formation when co-injected with MSCs into the mouse mammary fat pad, but no tumor was formed when five or ten 4T1 cells were implanted alone. The elevation of tumorigenic potential was further supported by gene expression analysis, which showed that when 4T1 cells were in contact with MSCs, several oncogenes, cancer markers, and tumor promoters were upregulated. Moreover, in vivo longitudinal fluorescence imaging of tumorigenesis revealed that MSCs created a vascularized environment which enhances the ability of 4T1 cells to colonize and proliferate. In conclusion, this study demonstrates that the promotion of mammary cancer progression by MSCs was achieved through the generation of a cancer-enhancing microenvironment to increase tumorigenic potential. These findings also suggest the potential risk of enhancing tumor progression in clinical cell therapy using MSCs. Attention has to be paid to patients with high risk of breast cancer when considering cell therapy with MSCs.

  13. Hypermethylated MAL gene – a silent marker of early colon tumorigenesis

    Directory of Open Access Journals (Sweden)

    Kallioniemi Anne

    2008-03-01

    Full Text Available Abstract Background Tumor-derived aberrantly methylated DNA might serve as diagnostic biomarkers for cancer, but so far, few such markers have been identified. The aim of the present study was to investigate the potential of the MAL (T-cell differentiation protein gene as an early epigenetic diagnostic marker for colorectal tumors. Methods Using methylation-specific polymerase chain reaction (MSP the promoter methylation status of MAL was analyzed in 218 samples, including normal mucosa (n = 44, colorectal adenomas (n = 63, carcinomas (n = 65, and various cancer cell lines (n = 46. Direct bisulphite sequencing was performed to confirm the MSP results. MAL gene expression was investigated with real time quantitative analyses before and after epigenetic drug treatment. Immunohistochemical analysis of MAL was done using normal colon mucosa samples (n = 5 and a tissue microarray with 292 colorectal tumors. Results Bisulphite sequencing revealed that the methylation was unequally distributed within the MAL promoter and by MSP analysis a region close to the transcription start point was shown to be hypermethylated in the majority of colorectal carcinomas (49/61, 80% as well as in adenomas (45/63, 71%. In contrast, only a minority of the normal mucosa samples displayed hypermethylation (1/23, 4%. The hypermethylation of MAL was significantly associated with reduced or lost gene expression in in vitro models. Furthermore, removal of the methylation re-induced gene expression in colon cancer cell lines. Finally, MAL protein was expressed in epithelial cells of normal colon mucosa, but not in the malignant cells of the same type. Conclusion Promoter hypermethylation of MAL was present in the vast majority of benign and malignant colorectal tumors, and only rarely in normal mucosa, which makes it suitable as a diagnostic marker for early colorectal tumorigenesis.

  14. Zebrafish neurofibromatosis type 1 genes have redundant functions in tumorigenesis and embryonic development

    Directory of Open Access Journals (Sweden)

    Jimann Shin

    2012-11-01

    Neurofibromatosis type 1 (NF1 is a common, dominantly inherited genetic disorder that results from mutations in the neurofibromin 1 (NF1 gene. Affected individuals demonstrate abnormalities in neural-crest-derived tissues that include hyperpigmented skin lesions and benign peripheral nerve sheath tumors. NF1 patients also have a predisposition to malignancies including juvenile myelomonocytic leukemia (JMML, optic glioma, glioblastoma, schwannoma and malignant peripheral nerve sheath tumors (MPNSTs. In an effort to better define the molecular and cellular determinants of NF1 disease pathogenesis in vivo, we employed targeted mutagenesis strategies to generate zebrafish harboring stable germline mutations in nf1a and nf1b, orthologues of NF1. Animals homozygous for loss-of-function alleles of nf1a or nf1b alone are phenotypically normal and viable. Homozygous loss of both alleles in combination generates larval phenotypes that resemble aspects of the human disease and results in larval lethality between 7 and 10 days post fertilization. nf1-null larvae demonstrate significant central and peripheral nervous system defects. These include aberrant proliferation and differentiation of oligodendrocyte progenitor cells (OPCs, dysmorphic myelin sheaths and hyperplasia of Schwann cells. Loss of nf1 contributes to tumorigenesis as demonstrated by an accelerated onset and increased penetrance of high-grade gliomas and MPNSTs in adult nf1a+/−; nf1b−/−; p53e7/e7 animals. nf1-null larvae also demonstrate significant motor and learning defects. Importantly, we identify and quantitatively analyze a novel melanophore phenotype in nf1-null larvae, providing the first animal model of the pathognomonic pigmentation lesions of NF1. Together, these findings support a role for nf1a and nf1b as potent tumor suppressor genes that also function in the development of both central and peripheral glial cells as well as melanophores in zebrafish.

  15. Over-expression of ST3Gal-I promotes mammary tumorigenesis.

    Science.gov (United States)

    Picco, Gianfranco; Julien, Sylvain; Brockhausen, Inka; Beatson, Richard; Antonopoulos, Aristotelis; Haslam, Stuart; Mandel, Ulla; Dell, Anne; Pinder, Sarah; Taylor-Papadimitriou, Joyce; Burchell, Joy

    2010-10-01

    Changes in glycosylation are common in malignancy, and as almost all surface proteins are glycosylated, this can dramatically affect the behavior of tumor cells. In breast carcinomas, the O-linked glycans are frequently truncated, often as a result of premature sialylation. The sialyltransferase ST3Gal-I adds sialic acid to the galactose residue of core 1 (Galbeta1,3GalNAc) O-glycans and this enzyme is over-expressed in breast cancer resulting in the expression of sialylated core 1 glycans. In order to study the role of ST3Gal-I in mammary tumor development, we developed transgenic mice that over-express the sialyltransferase under the control of the human membrane-bound mucin 1 promoter. These mice were then crossed with PyMT mice that spontaneously develop mammary tumors. As expected, ST3Gal-I transgenic mice showed increased activity and expression of the enzyme in the pregnant and lactating mammary glands, the stomach, lungs and intestine. Although no obvious defects were observed in the fully developed mammary gland, when these mice were crossed with PyMT mice, a highly significant decrease in tumor latency was observed compared to the PyMT mice on an identical background. These results indicate that ST3Gal-I is acting as a tumor promoter in this model of breast cancer. This, we believe, is the first demonstration that over-expression of a glycosyltransferase involved in mucin-type O-linked glycosylation can promote tumorigenesis.

  16. Nisin ZP, a Bacteriocin and Food Preservative, Inhibits Head and Neck Cancer Tumorigenesis and Prolongs Survival.

    Directory of Open Access Journals (Sweden)

    Pachiyappan Kamarajan

    Full Text Available The use of small antimicrobial peptides or bacteriocins, like nisin, to treat cancer is a new approach that holds great promise. Nisin exemplifies this new approach because it has been used safely in humans for many years as a food preservative, and recent laboratory studies support its anti-tumor potential in head and neck cancer. Previously, we showed that nisin (2.5%, low content has antitumor potential in head and neck squamous cell carcinoma (HNSCC in vitro and in vivo. The current studies explored a naturally occurring variant of nisin (nisin ZP; 95%, high content for its antitumor effects in vitro and in vivo. Nisin ZP induced the greatest level of apoptosis in HNSCC cells compared to low content nisin. HNSCC cells treated with increasing concentrations of nisin ZP exhibited increasing levels of apoptosis and decreasing levels of cell proliferation, clonogenic capacity, and sphere formation. Nisin ZP induced apoptosis through a calpain-dependent pathway in HNSCC cells but not in human oral keratinocytes. Nisin ZP also induced apoptosis dose-dependently in human umbilical vein endothelial cells (HUVEC with concomitant decreases in vascular sprout formation in vitro and reduced intratumoral microvessel density in vivo. Nisin ZP reduced tumorigenesis in vivo and long-term treatment with nisin ZP extended survival. In addition, nisin treated mice exhibited normal organ histology with no evidence of inflammation, fibrosis or necrosis. In summary, nisin ZP exhibits greater antitumor effects than low content nisin, and thus has the potential to serve as a novel therapeutic for HNSCC.

  17. PPARδ activation acts cooperatively with 3-phosphoinositide-dependent protein kinase-1 to enhance mammary tumorigenesis.

    Directory of Open Access Journals (Sweden)

    Claire B Pollock

    Full Text Available Peroxisome proliferator-activated receptorδ (PPARδ is a transcription factor that is associated with metabolic gene regulation and inflammation. It has been implicated in tumor promotion and in the regulation of 3-phosphoinositide-dependent kinase-1 (PDK1. PDK1 is a key regulator of the AGC protein kinase family, which includes the proto-oncogene AKT/PKB implicated in several malignancies, including breast cancer. To assess the role of PDK1 in mammary tumorigenesis and its interaction with PPARδ, transgenic mice were generated in which PDK1 was expressed in mammary epithelium under the control of the MMTV enhancer/promoter region. Transgene expression increased pT308AKT and pS9GSK3β, but did not alter phosphorylation of mTOR, 4EBP1, ribosomal protein S6 and PKCα. The transgenic mammary gland also expressed higher levels of PPARδ and a gene expression profile resembling wild-type mice maintained on a diet containing the PPARδ agonist, GW501516. Both wild-type and transgenic mice treated with GW501516 exhibited accelerated rates of tumor formation that were more pronounced in transgenic animals. GW501516 treatment was accompanied by a distinct metabolic gene expression and metabolomic signature that was not present in untreated animals. GW501516-treated transgenic mice expressed higher levels of fatty acid and phospholipid metabolites than treated wild-type mice, suggesting the involvement of PDK1 in enhancing PPARδ-driven energy metabolism. These results reveal that PPARδ activation elicits a distinct metabolic and metabolomic profile in tumors that is in part related to PDK1 and AKT signaling.

  18. The ING gene family in the regulation of cell growth and tumorigenesis.

    Science.gov (United States)

    Coles, Andrew H; Jones, Stephen N

    2009-01-01

    The five members of the inhibitor of growth (ING) gene family have garnered significant interest due to their putative roles as tumor suppressors. However, the precise role(s) of these ING proteins in regulating cell growth and tumorigenesis remains uncertain. Biochemical and molecular biological analysis has revealed that all ING members encode a PHD finger motif proposed to bind methylated histones and phosphoinosital, and all ING proteins have been found as components of large chromatin remodeling complexes that also include histone acetyl transferase (HAT) and histone deacetylase (HDAC) enzymes, suggesting a role for ING proteins in regulating gene transcription. Additionally, the results of forced overexpression studies performed in tissue culture have indicated that several of the ING proteins can interact with the p53 tumor suppressor protein and/or the nuclear factor-kappa B (NF-kappaB) protein complex. As these ING-associated proteins play well-established roles in numerous cell processes, including DNA repair, cell growth and survival, inflammation, and tumor suppression, several models have been proposed that ING proteins act as key regulators of cell growth not only through their ability to modify gene transcription but also through their ability to alter p53 and NF-kappaB activity. However, these models have yet to be substantiated by in vivo experimentation. This review summarizes what is currently known about the biological functions of the five ING genes based upon in vitro experiments and recent mouse modeling efforts, and will highlight the potential impact of INGs on the development of cancer.

  19. Maspin expression and its clinicopathological significance in tumorigenesis and progression of gastric cancer

    Institute of Scientific and Technical Information of China (English)

    Meng-Chun Wang; Yan-Min Yang; Xiao-Han Li; Fang Dong; Yan Li

    2004-01-01

    AIM: To investigate maspin expression in tumorigenesis and progression of gastric cancer and to explore its relevant molecular mechanisms.METHODS: Formalin-fixed and paraffin-embedded tissues from normal mucosa (n=182), dysplasia (n=69), cancer (n=113) of the stomach were studied for maspin expression by immunohistochemistry. Microvessel density (MVD) in gastric cancer was labeled using anti-CD34 antibody. Maspin expression was compared with clinical parameters and MVD of tumors. Caspase-3 expression was also detected in gastric carcinoma by immunohistochemistry. The relationship between Caspase-3 and maspin expression was concerned as well.RESULTS: The positive rates of maspin expression were 79.8%(145/182), 75.4%(52/69) and 50.4%(57/113) in normal mucosa, dysplasia and cancer of the stomach,respectively. Cancer less frequently expressed maspin than normal mucosa and dysplasia (P<0.05). Maspin expression showed a significantly negative association with invasive depth, metastasis, Lauren's and Nakamura's classification (P<0.05), but not with tumor size, Borrmann's classification,growth pattern or TNM staging (P>0.05). The positive rate of Caspase-3 was significantly lower in gastric cancer than in normal gastric mucosa (P<0.05,32.7% vs 50.4%). It was noteworthy that maspin expression was negatively correlated with MVD, but positively correlated with expression of Caspase-3 in gastric cancer (P<0.05).CONCLUSION: Down-regulated maspin expression is a late molecular event in gastric carcinogenesis. Reduced expression of maspin contributes to progression of gastric cancer probably by inhibiting cell adhesion, enhancing cell mobility,decreasing cell apoptosis and facilitating angiogenesis.Additionally altered expression of maspin underlies the molecular mechanism of differentiation of gastric cancer and supports the different histogenetic pathways of intestinal and diffuse gastric cancers. Maspin expression can be considered as an effective and objective

  20. Loss of disabled-2 expression is an early event in esophageal squamous tumorigenesis

    Institute of Scientific and Technical Information of China (English)

    Kumar Anupam; Chatopadhyay Tusharkant; Siddhartha Datta Gupta; Ralhan Ranju

    2006-01-01

    AIM: Disabled-2 (D4B2) is a candidate tumor-suppressor gene identified in ovarian cancer that negatively influences mitogenic signal transduction of growth factors and blocks ras activity. In a recent study, we observed down-regulation of DAB2 transcripts in ESCCs using cDNA microarrays. In the present study, we aimed to determine the clinical significance of loss of DAB2protein in esophageal tumorigenesis, hypothesizing that DAB2 promoter hypermethylation-mediated gene silencing may account for loss of the protein.METHODS: DAB2 expression was analyzed by immunohistochemistry in 50 primary esophageal squamous cell carcinomas (ESCCs), 30 distinct hyperplasia, 15 dysplasia and 10 non-malignant esophageal tissues. To determine whether promoter hypermethylation contributes to loss of DAB2 expression in ESCCs, methylation status of DAB2 promoter was analyzed in DAB2 immuno-negative tumors using methylation-specific PCR.RESULTS: Loss of DAB2 protein was observed in 5/30 (17%) hyperplasia, 10/15 (67%) dysplasia and 34/50 (68%) ESCCs. Significant loss of DAB2 protein was observed from esophageal normal mucosa to hyperplasia, dysplasia and invasive cancer (Ptrend < 0.001).Promoter hypermethylation of DAB2 was observed in 2of 10 (20%) DAB2 immuno-negative ESCCs.CONCLUSION: Loss of DAB2 protein expression occurs in early pre-neoplastic stages of development of esophageal cancer and is sustained down the tumorigenic pathway. Infrequent DAB2 promoter methylation in ESCCs suggests that epigenetic gene silencing is only one of the mechanisms causing loss of DAB2 expression in ESCCs.

  1. Cooperation of the BTB-Zinc finger protein, Abrupt, with cytoskeletal regulators in Drosophila epithelial tumorigenesis

    Directory of Open Access Journals (Sweden)

    Nezaket Turkel

    2015-08-01

    Full Text Available The deregulation of cell polarity or cytoskeletal regulators is a common occurrence in human epithelial cancers. Moreover, there is accumulating evidence in human epithelial cancer that BTB-ZF genes, such as Bcl6 and ZBTB7A, are oncogenic. From our previous studies in the vinegar fly, Drosophila melanogaster, we have identified a cooperative interaction between a mutation in the apico-basal cell polarity regulator Scribble (Scrib and overexpression of the BTB-ZF protein Abrupt (Ab. Herein, we show that co-expression of ab with actin cytoskeletal regulators, RhoGEF2 or Src64B, in the developing eye-antennal epithelial tissue results in the formation of overgrown amorphous tumours, whereas ab and DRac1 co-expression leads to non-cell autonomous overgrowth. Together with ab, these genes affect the expression of differentiation genes, resulting in tumours locked in a progenitor cell fate. Finally, we show that the expression of two mammalian genes related to ab, Bcl6 and ZBTB7A, which are oncogenes in mammalian epithelial cancers, significantly correlate with the upregulation of cytoskeletal genes or downregulation of apico-basal cell polarity neoplastic tumour suppressor genes in colorectal, lung and other human epithelial cancers. Altogether, this analysis has revealed that upregulation of cytoskeletal regulators cooperate with Abrupt in Drosophila epithelial tumorigenesis, and that high expression of human BTB-ZF genes, Bcl6 and ZBTB7A, shows significant correlations with cytoskeletal and cell polarity gene expression in specific epithelial tumour types. This highlights the need for further investigation of the cooperation between these genes in mammalian systems.

  2. Discoidin domain receptor 1 contributes to tumorigenesis through modulation of TGFBI expression.

    Science.gov (United States)

    Rudra-Ganguly, Nandini; Lowe, Christine; Mattie, Michael; Chang, Mi Sook; Satpayev, Daulet; Verlinsky, Alla; An, Zili; Hu, Liping; Yang, Peng; Challita-Eid, Pia; Stover, David R; Pereira, Daniel S

    2014-01-01

    Discoidin domain receptor 1 (DDR1) is a member of the receptor tyrosine kinase family. The receptor is activated upon binding to its ligand, collagen, and plays a crucial role in many fundamental processes such as cell differentiation, adhesion, migration and invasion. Although DDR1 is expressed in many normal tissues, upregulated expression of DDR1 in a variety of human cancers such as lung, colon and brain cancers is known to be associated with poor prognosis. Using shRNA silencing, we assessed the oncogenic potential of DDR1. DDR1 knockdown impaired tumor cell proliferation and migration in vitro and tumor growth in vivo. Microarray analysis of tumor cells demonstrated upregulation of TGFBI expression upon DDR1 knockdown, which was subsequently confirmed at the protein level. TGFBI is a TGFβ-induced extracellular matrix protein secreted by the tumor cells and is known to act either as a tumor promoter or tumor suppressor, depending on the tumor environment. Here, we show that exogenous addition of recombinant TGFBI to BXPC3 tumor cells inhibited clonogenic growth and migration, thus recapitulating the phenotypic effect observed from DDR1 silencing. BXPC3 tumor xenografts demonstrated reduced growth with DDR1 knockdown, and the same xenograft tumors exhibited an increase in TGFBI expression level. Together, these data suggest that DDR1 expression level influences tumor growth in part via modulation of TGFBI expression. The reciprocal expression of DDR1 and TGFBI may help to elucidate the contribution of DDR1 in tumorigenesis and TGFBI may also be used as a biomarker for the therapeutic development of DDR1 specific inhibitors.

  3. Discoidin domain receptor 1 contributes to tumorigenesis through modulation of TGFBI expression.

    Directory of Open Access Journals (Sweden)

    Nandini Rudra-Ganguly

    Full Text Available Discoidin domain receptor 1 (DDR1 is a member of the receptor tyrosine kinase family. The receptor is activated upon binding to its ligand, collagen, and plays a crucial role in many fundamental processes such as cell differentiation, adhesion, migration and invasion. Although DDR1 is expressed in many normal tissues, upregulated expression of DDR1 in a variety of human cancers such as lung, colon and brain cancers is known to be associated with poor prognosis. Using shRNA silencing, we assessed the oncogenic potential of DDR1. DDR1 knockdown impaired tumor cell proliferation and migration in vitro and tumor growth in vivo. Microarray analysis of tumor cells demonstrated upregulation of TGFBI expression upon DDR1 knockdown, which was subsequently confirmed at the protein level. TGFBI is a TGFβ-induced extracellular matrix protein secreted by the tumor cells and is known to act either as a tumor promoter or tumor suppressor, depending on the tumor environment. Here, we show that exogenous addition of recombinant TGFBI to BXPC3 tumor cells inhibited clonogenic growth and migration, thus recapitulating the phenotypic effect observed from DDR1 silencing. BXPC3 tumor xenografts demonstrated reduced growth with DDR1 knockdown, and the same xenograft tumors exhibited an increase in TGFBI expression level. Together, these data suggest that DDR1 expression level influences tumor growth in part via modulation of TGFBI expression. The reciprocal expression of DDR1 and TGFBI may help to elucidate the contribution of DDR1 in tumorigenesis and TGFBI may also be used as a biomarker for the therapeutic development of DDR1 specific inhibitors.

  4. Dietary Feeding of Grape Seed Extract Prevents Intestinal Tumorigenesis in APCmin/+ Mice

    Directory of Open Access Journals (Sweden)

    Balaiya Velmurugan

    2010-01-01

    Full Text Available Chemopreventive effects and associated mechanisms of grape seed extract (GSE against intestinal/colon cancer development are largely unknown. Herein, we investigated GSE efficacy against intestinal tumorigenesis in APCmin/+ mice. Female APCmin/+ mice were fed control or 0.5% GSE (wt/wt mixed AIN-76A diet for 6 weeks. At the end of the experiment, GSE feeding decreased the total number of intestinal polyps by 40%. The decrease in polyp formation in the small intestine was 42%, which was mostly in its middle (51% and distal (49% portions compared with the proximal one. GSE also decreased polyp growth where the number of polyps of 1 to 2 mm in size decreased by 42% and greater than 2 mm in size by 71%, without any significant change in polyps less than 1 mm in size. Immunohistochemical analyses of small intestinal tissue samples revealed a decrease (80%–86% in cell proliferation and an increase (four- to eight-fold in apoptosis. GSE feeding also showed decreased protein levels of cyclooxygenase-2 (COX-2 (56%–64%, inducible nitric oxide synthase (iNOS (58%–60%, and β-catenin (43%–59% but an increased Cip1/p21-positive cells (1.9- to 2.6-fold. GSE also decreased cyclin D1 and c-Myc protein levels in small intestine. Together, these findings show the chemopreventive potential of GSE against intestinal polyp formation and growth in APCmin/+ mice, which was accompanied with reduced cell proliferation and increased apoptosis together with down-regulation in COX-2, iNOS, β-catenin, cyclin D1, and c-Myc expression, but increased Cip1/p21. In conclusion, the present study suggests potential usefulness of GSE for the chemoprevention of human intestinal/colorectal cancer.

  5. Proprotein Convertase Subtilisin/Kexin Type 9 Deficiency Reduces Melanoma Metastasis in Liver

    Directory of Open Access Journals (Sweden)

    Xiaowei Sun

    2012-12-01

    Full Text Available High circulating cholesterol is associated with hypercholesterolemia, atherosclerosis, and stroke. However, the relation between cholesterol and tumorigenesis/metastasis is controversial. The proprotein convertase subtilisin/kexin type 9 (PCSK9 regulates low-density lipoprotein cholesterol homeostasis by targeting the low-density lipoprotein receptor (LDLR for degradation. PCSK9 is mostly expressed in liver, which is one of the most common sites for metastatic disease. To reveal the function of PCSK9 and also evaluate the impact of cholesterol in liver metastasis development, B16F1 melanoma cells were injected into wild-type (WT and Pcsk9-/- mice to induce liver metastasis. On chow diet, Pcsk9-/- mice harbored two-fold less liver metastases than WT mice. This decrease is related to low cholesterol levels in Pcsk9-/- mice, as the protection was lost after normalizing Pcsk9-/- cholesterol levels by a 2-week high cholesterol diet. Furthermore, a prolongation of this diet strongly increased metastasis in both genotypes, suggesting that high cholesterol levels promote metastatic progression. The protective effect of the PCSK9 deficiency is also associated with increased apoptosis in liver stroma and metastases. Tumor necrosis factor.α (TNFα mRNA and protein were, respectively, higher in liver stroma and plasma of injected mice, likely increasing the apoptotic TNFα signaling. Furthermore, the anti-apoptotic factor B-cell lymphoma 2 was downregulated. TNFα regulation is LDLR-independent, as its mRNA level was similarly upregulated in mice lacking both PCSK9 and LDLR. Our findings show that PCSK9 deficiency reduces liver metastasis by its ability to lower cholesterol levels and by possibly enhancing TNFα-mediated apoptosis.

  6. Liver transplantation for polycystic liver and massive hepatomegaly

    Institute of Scientific and Technical Information of China (English)

    Salvatore; Gruttadauria; Fabrizio; di; Francesco; Bruno; Gridelli

    2010-01-01

    Liver tumor and other benign liver diseases such as polycystic liver disease can cause massive hepatomegaly and may represent an indication for liver transplantation(LT)in some instances.In this setting,LT can be extremely difficult and challenging due to its decreased mobility and access to vascular supply.Benefit from either a right or a left partial liver resection during the transplant procedure has been advocated to safely accomplish the hepatectomy of the native liver.Although we believe that partial ...

  7. Evidence for a Role of the Transcriptional Regulator Maid in Tumorigenesis and Aging.

    Directory of Open Access Journals (Sweden)

    Koichi Fujisawa

    Full Text Available Maid is a helix-loop-helix protein that is involved in cell proliferation. In order to further elucidate its physiological functions, we studied Maid activity in two small fish model systems. We found that Maid expression was greatest in zebrafish liver and that it increased following partial hepatectomy. Maid levels were also high in hepatic preneoplastic foci induced by treatment of zebrafish with diethylnitrosamine (DEN, but low in hepatocellular carcinomas (HCC, mixed tumors, and cholangiocarcinomas developing in these animals. In DEN-treated transgenic medaka overexpressing Maid, hepatic BrdU uptake and proliferation were reduced. After successive breedings, Maid transgenic medaka exhibited decreased movement and a higher incidence of abnormal spine curvature, possibly due to the senescence of spinal cord cells. Taken together, our results suggest that Maid levels can influence the progression of liver cancer. In conclusion, we found that Maid is important regulator of hepatocarconogenesis and aging.

  8. In Drosophila, RhoGEF2 cooperates with activated Ras in tumorigenesis through a pathway involving Rho1–Rok–Myosin-II and JNK signalling

    Directory of Open Access Journals (Sweden)

    Peytee Khoo

    2013-05-01

    The Ras oncogene contributes to ∼30% of human cancers, but alone is not sufficient for tumorigenesis. In a Drosophila screen for oncogenes that cooperate with an activated allele of Ras (RasACT to promote tissue overgrowth and invasion, we identified the GTP exchange factor RhoGEF2, an activator of Rho-family signalling. Here, we show that RhoGEF2 also cooperates with an activated allele of a downstream effector of Ras, Raf (RafGOF. We dissect the downstream pathways through which RhoGEF2 cooperates with RasACT (and RafGOF, and show that RhoGEF2 requires Rho1, but not Rac, for tumorigenesis. Furthermore, of the Rho1 effectors, we show that RhoGEF2 + Ras (Raf-mediated tumorigenesis requires the Rho kinase (Rok–Myosin-II pathway, but not Diaphanous, Lim kinase or protein kinase N. The Rho1–Rok–Myosin-II pathway leads to the activation of Jun kinase (JNK, in cooperation with RasACT. Moreover, we show that activation of Rok or Myosin II, using constitutively active transgenes, is sufficient for cooperative tumorigenesis with RasACT, and together with RasACT leads to strong activation of JNK. Our results show that Rok–Myosin-II activity is necessary and sufficient for Ras-mediated tumorigenesis. Our observation that activation of Myosin II, which regulates Filamentous actin (F-actin contractility without affecting F-actin levels, cooperates with RasACT to promote JNK activation and tumorigenesis, suggests that increased cell contractility is a key factor in tumorigenesis. Furthermore, we show that signalling via the Tumour necrosis factor (TNF; also known as Egr-ligand–JNK pathway is most likely the predominant pathway that activates JNK upon Rok activation. Overall, our analysis highlights the need for further analysis of the Rok–Myosin-II pathway in cooperation with Ras in human cancers.

  9. Gut microbiota and liver diseases.

    Science.gov (United States)

    Minemura, Masami; Shimizu, Yukihiro

    2015-02-14

    Several studies revealed that gut microbiota are associated with various human diseases, e.g., metabolic diseases, allergies, gastroenterological diseases, and liver diseases. The liver can be greatly affected by changes in gut microbiota due to the entry of gut bacteria or their metabolites into the liver through the portal vein, and the liver-gut axis is important to understand the pathophysiology of several liver diseases, especially non-alcoholic fatty liver disease and hepatic encephalopathy. Moreover, gut microbiota play a significant role in the development of alcoholic liver disease and hepatocarcinogenesis. Based on these previous findings, trials using probiotics have been performed for the prevention or treatment of liver diseases. In this review, we summarize the current understanding of the changes in gut microbiota associated with various liver diseases, and we describe the therapeutic trials of probiotics for those diseases.

  10. STAT3 activation in monocytes accelerates liver cancer progression

    Directory of Open Access Journals (Sweden)

    Wu Wen-Yong

    2011-12-01

    Full Text Available Abstract Background Signal transducer and activator of transcription 3 (STAT3 is an important transcription factor ubiquitously expressed in different cell types. STAT3 plays an essential role in cell survival, proliferation, and differentiation. Aberrantly hyper-activated STAT3 signaling in cancer cells and in the tumor microenvironment has been detected in a wide variety of human cancers and is considered an important factor for cancer initiation, development, and progression. However, the role of STAT3 activation in monocytes in the development of HCC has not been well understood. Methods Immunohistochemical analysis of phosphorylated STAT3 was performed on tissue microarray from HCC patients. Using a co-culture system in vivo, HCC cell growth was determined by the MTT assay. In vivo experiments were conducted with mice given diethylinitrosamine (DEN, which induces HCC was used to investigate the role of STAT3 expression in monocytes on tumor growth. Real-time PCR was used to determine the expression of cell proliferation and cell arrest associated genes in the tumor and nontumor tissue from liver. Results Phosphorylated STAT3 was found in human hepatocellular carcinoma tissue samples and was expressed in tumor cells and also in monocytes. Phosphorylated STAT3 expression in monocyte was significantly correlated to advanced clinical stage of HCC and a poor prognosis. Using a co-culture system in vivo, monocytes promoted HCC cell growth via the IL-6/STAT3 signaling pathway. The STAT3 inhibitor, NSC 74859, significantly suppressed tumor growth in vivo in mice with diethylinitrosamine (DEN-induced HCC. In this animal model, blockade of STAT3 with NSC 74859 induced tumor cell apoptosis, while inhibiting both tumor cells and monocytes proliferation. Furthermore, NSC 74859 treatment suppressed cancer associated inflammation in DEN-induce HCC. Conclusion Our data suggest constitutively activated STAT3 monocytes promote liver tumorigenesis in clinical

  11. Novel therapeutic Strategies for Targeting Liver Cancer Stem Cells

    Directory of Open Access Journals (Sweden)

    Naoki Oishi, Xin Wei Wang

    2011-01-01

    Full Text Available The cancer stem cell (CSC hypothesis was first proposed over 40 years ago. Advances in CSC isolation were first achieved in hematological malignancies, with the first CSC demonstrated in acute myeloid leukemia. However, using similar strategies and technologies, and taking advantage of available surface markers, CSCs have been more recently demonstrated in a growing range of epithelial and other solid organ malignancies, suggesting that the majority of malignancies are dependent on such a compartment.Primary liver cancer consists predominantly of hepatocellular carcinoma (HCC and intrahepatic cholangiocarcinoma (ICC. It is believed that hepatic progenitor cells (HPCs could be the origin of some HCCs and ICCs. Furthermore, stem cell activators such as Wnt/β-catenin, TGF-β, Notch and Hedgehog signaling pathways also expedite tumorigenesis, and these pathways could serve as molecular targets to assist in designing cancer prevention strategies. Recent studies indicate that additional factors such as EpCAM, Lin28 or miR-181 may also contribute to HCC progression by targeting HCC CSCs. Various therapeutic drugs that directly modulate CSCs have been examined in vivo and in vitro. However, CSCs clearly have a complex pathogenesis, with a considerable crosstalk and redundancy in signaling pathways, and hence targeting single molecules or pathways may have a limited benefit for treatment. Many of the key signaling molecules are shared by both CSCs and normal stem cells, which add further challenges for designing molecularly targeted strategies specific to CSCs but sparing normal stem cells to avoid side effects. In addition to the direct control of CSCs, many other factors that are needed for the maintenance of CSCs, such as angiogenesis, vasculogenesis, invasion and migration, hypoxia, immune evasion, multiple drug resistance, and radioresistance, should be taken into consideration when designing therapeutic strategies for HCC.Here we provide a brief

  12. [Alcoholic liver disease and liver transplantation].

    Science.gov (United States)

    Testino, Gianni; Patussi, Valentino; Scafato, Emanuele

    2013-01-01

    Alcoholic liver disease (ALD) is the second most common diagnosis among patients undergoing liver transplantation (LT) in Europe and in the United States. The outcome of patients transplanted for ALD is at least as good as that for most other diagnoses and better than that for hepatitis C virus. In case of severe acute alcoholic hepatitis (AAH) non-responders to medical therapy, the reason for denying LT is that it requires abstinence from alcohol for six months before consideration for a transplant. A strict application of a period of abstinence as a policy for transplant eligibility is unfair to non-responder patients, as most of them will have died prior to the end of the six-month sober period. In our opinion, in severe AAH subjects with a good social support, with the frequency of self-help groups (alcoholics anonymous or association of clubs of alcoholics in treatment), with the frequency of Alcohol Unit and without severe psychotic or personality disorders, the lack of pre-LT abstinence alone should not be a barrier against being listed.

  13. Liver transplantation in Germany.

    Science.gov (United States)

    Tacke, Frank; Kroy, Daniela C; Barreiros, Ana Paula; Neumann, Ulf P

    2016-08-01

    Liver transplantation (LT) is a well-accepted procedure for end-stage liver disease in Germany. In 2015, 1489 patients were admitted to the waiting list (including 1308 new admissions), with the leading etiologies being fibrosis and cirrhosis (n = 349), alcoholic liver disease (n = 302), and hepatobiliary malignancies (n = 220). Organ allocation in Germany is regulated within the Eurotransplant system based on urgency as expressed by the Model for End-Stage Liver Disease score. In 2015, only 894 LTs (n = 48 from living donors) were performed at 23 German transplant centers, reflecting a shortage of organs. Several factors may contribute to the low number of organ donations. The German transplant legislation only accepts donation after brain death (not cardiac death), whereas advances in neurosurgery and a more frequently requested "palliative care" approach render fewer patients suitable as potential donors. The legislation further requires the active consent of the donor or first-degree relatives before donation. Ongoing debates within the German transplant field address the optimal management of patients with alcoholic liver cirrhosis, hepatocellular carcinoma (HCC), and cholangiocarcinoma and measures to increase living donor transplantations. As a result of irregularities at mainly 4 German transplant centers that were exposed in 2012, guiding principles updated by the German authorities have since implemented strict rules (including internal and external auditing, the 8-eyes principle, mandatory repeated testing for alcohol consumption) to prohibit any manipulations in organ allocation. In conclusion, we will summarize important aspects on the management of LT in Germany, discuss legal and organizational aspects, and highlight challenges mainly related to the relative lack of organ donations, increasing numbers of extended criteria donors, and the peculiarities of the recipient patients. Liver Transplantation 22 1136-1142 2016 AASLD.

  14. PGE2 receptor EP2 mediates the antagonistic effect of COX-2 on TGF-beta signaling during mammary tumorigenesis.

    Science.gov (United States)

    Tian, Maozhen; Schiemann, William P

    2010-04-01

    The molecular mechanisms that enable cyclooxygenase-2 (COX-2) and its mediator prostaglandin E2 (PGE2) to inhibit transforming growth factor-beta (TGF-beta) signaling during mammary tumorigenesis remain unknown. We show here that TGF-beta selectively stimulated the expression of the PGE2 receptor EP2, which increased normal and malignant mammary epithelial cell (MEC) invasion, anchorage-independent growth, and resistance to TGF-beta-induced cytostasis. Mechanistically, elevated EP2 expression in normal MECs inhibited the coupling of TGF-beta to Smad2/3 activation and plasminogen activator inhibitor-1 (PAI1) expression, while EP2 deficiency in these same MECs augmented Smad2/3 activation and PAI expression stimulated by TGF-beta. Along these lines, engineering malignant MECs to lack EP2 expression prevented their growth in soft agar, restored their cytostatic response to TGF-beta, decreased their invasiveness in response to TGF-beta, and potentiated their activation of Smad2/3 and expression of PAI stimulated by TGF-beta. More important, we show that COX-2 or EP2 deficiency both significantly decreased the growth, angiogenesis, and pulmonary metastasis of mammary tumors produced in mice. Collectively, this investigation establishes EP2 as a potent mediator of the anti-TGF-beta activities elicited by COX-2/PGE2 in normal and malignant MECs. Our findings also suggest that pharmacological targeting of EP2 receptors may provide new inroads to antagonize the oncogenic activities of TGF-beta during mammary tumorigenesis.-Tian, M., Schiemann, W. P. PGE2 receptor EP2 mediates the antagonistic effect of COX-2 on TGF-beta signaling during mammary tumorigenesis.

  15. PGE2 receptor EP2 mediates the antagonistic effect of COX-2 on TGF-β signaling during mammary tumorigenesis

    Science.gov (United States)

    Tian, Maozhen; Schiemann, William P.

    2010-01-01

    The molecular mechanisms that enable cyclooxygenase-2 (COX-2) and its mediator prostaglandin E2 (PGE2) to inhibit transforming growth factor-β (TGF-β) signaling during mammary tumorigenesis remain unknown. We show here that TGF-β selectively stimulated the expression of the PGE2 receptor EP2, which increased normal and malignant mammary epithelial cell (MEC) invasion, anchorage-independent growth, and resistance to TGF-β-induced cytostasis. Mechanistically, elevated EP2 expression in normal MECs inhibited the coupling of TGF-β to Smad2/3 activation and plasminogen activator inhibitor-1 (PAI1) expression, while EP2 deficiency in these same MECs augmented Smad2/3 activation and PAI expression stimulated by TGF-β. Along these lines, engineering malignant MECs to lack EP2 expression prevented their growth in soft agar, restored their cytostatic response to TGF-β, decreased their invasiveness in response to TGF-β, and potentiated their activation of Smad2/3 and expression of PAI stimulated by TGF-β. More important, we show that COX-2 or EP2 deficiency both significantly decreased the growth, angiogenesis, and pulmonary metastasis of mammary tumors produced in mice. Collectively, this investigation establishes EP2 as a potent mediator of the anti-TGF-β activities elicited by COX-2/PGE2 in normal and malignant MECs. Our findings also suggest that pharmacological targeting of EP2 receptors may provide new inroads to antagonize the oncogenic activities of TGF-β during mammary tumorigenesis.—Tian, M., Schiemann, W. P. PGE2 receptor EP2 mediates the antagonistic effect of COX-2 on TGF-β signaling during mammary tumorigenesis. PMID:19897661

  16. SOX2 gene regulates the transcriptional network of oncogenes and affects tumorigenesis of human lung cancer cells.

    Directory of Open Access Journals (Sweden)

    Si Chen

    Full Text Available Recent studies demonstrated that cancer stem cells (CSCs have higher tumorigenesis properties than those of differentiated cancer cells and that transcriptional factor-SOX2 plays a vital role in maintaining the unique properties of CSCs; however, the function and underlying mechanism of SOX2 in carcinogenesis of lung cancer are still elusive. This study applied immunohistochemistry to analyze the expression of SOX2 in human lung tissues of normal individuals as well as patients with adenocarcinoma, squamous cell carcinoma, and large cell and small cell carcinoma and demonstrated specific overexpression of SOX2 in all types of lung cancer tissues. This finding supports the notion that SOX2 contributes to the tumorigenesis of lung cancer cells and can be used as a diagnostic probe. In addition, obviously higher expression of oncogenes c-MYC, WNT1, WNT2, and NOTCH1 was detected in side population (SP cells than in non-side population (NSP cells of human lung adenocarcinoma cell line-A549, revealing a possible mechanism for the tenacious tumorigenic potential of CSCs. To further elucidate the function of SOX2 in tumorigenesis of cancer cells, A549 cells were established with expression of luciferase and doxycycline-inducible shRNA targeting SOX2. We found silencing of SOX2 gene reduces the tumorigenic property of A549 cells with attenuated expression of c-MYC, WNT1, WNT2, and NOTCH1 in xenografted NOD/SCID mice. By using the RNA-Seq method, an additional 246 target cancer genes of SOX2 were revealed. These results present evidence that SOX2 may regulate the expression of oncogenes in CSCs to promote the development of human lung cancer.

  17. TAZ induces lung cancer stem cell properties and tumorigenesis by up-regulating ALDH1A1.

    Science.gov (United States)

    Yu, Jihang; Alharbi, Adel; Shan, Hongchao; Hao, Yawei; Snetsinger, Brooke; Rauh, Michael J; Yang, Xiaolong

    2017-06-13

    Recent studies suggest that lung cancer stem cells (CSCs) may play major roles in lung cancer. Therefore, identification of lung CSC drivers may provide promising targets for lung cancer. TAZ is a transcriptional co-activator and key downstream effector of the Hippo pathway, which plays critical roles in various biological processes. TAZ has been shown to be overexpressed in lung cancer and involved in tumorigenicity of lung epithelial cells. However, whether TAZ is a driver for lung CSCs and tumor formation in vivo is unknown. In addition, the molecular mechanism underlying TAZ-induced lung tumorigenesis remains to be determined. In this study, we provided evidence that constitutively active TAZ (TAZ-S89A) is a driver for lung tumorigenesis in vivo in mice and formation of lung CSC. Further RNA-seq and qRT-PCR analysis identified Aldh1a1, a well-established CSC marker, as critical TAZ downstream target and showed that TAZ induces Aldh1a1 transcription by activating its promoter activity through interaction with the transcription factor TEAD. Most significantly, inhibition of ALDH1A1 with its inhibitor A37 or CRISPR gene knockout in lung cancer cells suppressed lung tumorigenic and CSC phenotypes in vitro, and tumor formation in mice in vivo. In conclusion, this study identified TAZ as a novel inducer of lung CSCs and the first transcriptional activator of the stem cell marker ALDH1A1. Most significantly, we identified ALDH1A1 as a critical meditator of TAZ-induced tumorigenic and CSC phenotypes in lung cancer. Our studies provided preclinical data for targeting of TAZ-TEAD-ALDH1A1 signaling to inhibit CSC-induced lung tumorigenesis in the future.

  18. EFFECTS OF MUTATION AND EXPRESSION OF PTEN GENE mRNA ON TUMORIGENESIS AND PROGRESSION OF EPITHELIAL OVARIAN CANCER

    Institute of Scientific and Technical Information of China (English)

    陈颖; 郑华川; 杨雪飞; 孙丽梅; 辛彦

    2004-01-01

    Objective To investigate the mutation and expression of tumor suppressor gene-PTEN mRNA and explore their roles in tumorigenesis and progression of ovarian cancer. Methods Mutated exon 5 of PTEN gene was examined in normal ovary (n = 5), ovarian cyst (n =5), ovarian borderline tumor (n=9), epithelial ovarian cancer (n=60), and ovarian cancer cell line (n= 1)by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP). mRNA expression of PTEN gene was evaluated in corresponding tissues and cell line by reverse transcription polymerase chain reaction(RT-PCR). The mutation and mRNA expression of PTEN gene were compared with clinicopathological features of ovarian cancer. Results Mutated exon 5 of PTEN gene was detected only in 5 (7.1%) cases of epithelial ovarian cancer. mRNA expression level of PTEN gene in ovarian borderline tumor or ovarian cancer was lower than that in normal ovary or ovarian cyst (P < 0.05). The level of PTEN gene mRNA expression was negatively correlated with clinicopathological staging of ovarian cancer, whereas positively correlated with histological differentiation (P < 0.05). mRNA expression level of PTEN gene in ovarian endometrioid cancer was significantly lower than that in ovarian serous or mucinous cancer (P < 0.05). Conclusions Mutation of PTEN gene occurs in ovarian cancer. Down-regulated expression of PTEN is probably an important molecular event in tumorigenesis of ovarian cancer. Abnormal expression of PTEN gene is involved in progression of ovarian cancer. Reduced expression of PTEN gene is closely associated with tumorigenesis and pathobiological behaviors of ovarian endometrioid cancer.

  19. SOX2 gene regulates the transcriptional network of oncogenes and affects tumorigenesis of human lung cancer cells.

    Science.gov (United States)

    Chen, Si; Xu, Yingxi; Chen, Yanan; Li, Xuefei; Mou, Wenjun; Wang, Lina; Liu, Yanhua; Reisfeld, Ralph A; Xiang, Rong; Lv, Dan; Li, Na

    2012-01-01

    Recent studies demonstrated that cancer stem cells (CSCs) have higher tumorigenesis properties than those of differentiated cancer cells and that transcriptional factor-SOX2 plays a vital role in maintaining the unique properties of CSCs; however, the function and underlying mechanism of SOX2 in carcinogenesis of lung cancer are still elusive. This study applied immunohistochemistry to analyze the expression of SOX2 in human lung tissues of normal individuals as well as patients with adenocarcinoma, squamous cell carcinoma, and large cell and small cell carcinoma and demonstrated specific overexpression of SOX2 in all types of lung cancer tissues. This finding supports the notion that SOX2 contributes to the tumorigenesis of lung cancer cells and can be used as a diagnostic probe. In addition, obviously higher expression of oncogenes c-MYC, WNT1, WNT2, and NOTCH1 was detected in side population (SP) cells than in non-side population (NSP) cells of human lung adenocarcinoma cell line-A549, revealing a possible mechanism for the tenacious tumorigenic potential of CSCs. To further elucidate the function of SOX2 in tumorigenesis of cancer cells, A549 cells were established with expression of luciferase and doxycycline-inducible shRNA targeting SOX2. We found silencing of SOX2 gene reduces the tumorigenic property of A549 cells with attenuated expression of c-MYC, WNT1, WNT2, and NOTCH1 in xenografted NOD/SCID mice. By using the RNA-Seq method, an additional 246 target cancer genes of SOX2 were revealed. These results present evidence that SOX2 may regulate the expression of oncogenes in CSCs to promote the development of human lung cancer.

  20. Cdk2 deficiency decreases ras/CDK4-dependent malignant progression, but not myc-induced tumorigenesis.

    Science.gov (United States)

    Macias, Everardo; Kim, Yongbaek; Miliani de Marval, Paula L; Klein-Szanto, Andres; Rodriguez-Puebla, Marcelo L

    2007-10-15

    We have previously shown that forced expression of CDK4 in mouse skin (K5CDK4 mice) results in increased susceptibility to squamous cell carcinoma (SCC) development in a chemical carcinogenesis protocol. This protocol induces skin papilloma development, causing a selection of cells bearing activating Ha-ras mutations. We have also shown that myc-induced epidermal proliferation and oral tumorigenesis (K5Myc mice) depends on CDK4 expression. Biochemical analysis of K5CDK4 and K5Myc epidermis as well as skin tumors showed that keratinocyte proliferation is mediated by CDK4 sequestration of p27Kip1 and p21Cip1, and activation of CDK2. Here, we studied the role of CDK2 in epithelial tumorigenesis. In normal skin, loss of CDK2 rescues CDK4-induced, but not myc-induced epidermal hyperproliferation. Ablation of CDK2 in K5CDK4 mice results in decreased incidences and multiplicity of skin tumors as well as malignant progression to SCC. Histopathologic analysis showed that K5CDK4 tumors are drastically more aggressive than K5CDK4/CDK2-/- tumors. On the other hand, we show that CDK2 is dispensable for myc-induced tumorigenesis. In contrast to our previous report of K5Myc/CDK4-/-, K5Myc/CDK2-/- mice developed oral tumors with the same frequency as K5Myc mice. Overall, we have established that ras-induced tumors are more susceptible to CDK2 ablation than myc-induced tumors, suggesting that the efficacy of targeting CDK2 in tumor development and malignant progression is dependent on the oncogenic pathway involved.

  1. Epigenetic reprogramming governs EcSOD expression during human mammary epithelial cell differentiation, tumorigenesis and metastasis.

    Science.gov (United States)

    Teoh-Fitzgerald, M L; Fitzgerald, M P; Zhong, W; Askeland, R W; Domann, F E

    2014-01-16

    Expression of the antioxidant enzyme EcSOD in normal human mammary epithelial cells was not recognized until recently. Although expression of EcSOD was not detectable in non-malignant human mammary epithelial cells (HMEC) cultured in conventional two-dimensional (2D) culture conditions, EcSOD protein expression was observed in normal human breast tissues, suggesting that the 2D-cultured condition induces a repressive status of EcSOD gene expression in HMEC. With the use of laminin-enriched extracellular matrix (lrECM), we were able to detect expression of EcSOD when HMEC formed polarized acinar structures in a 3D-culture condition. Repression of the EcSOD-gene expression was again seen when the HMEC acini were sub-cultured as a monolayer, implying that lrECM-induced acinar morphogenesis is essential in EcSOD-gene activation. We have further shown the involvement of DNA methylation in regulating EcSOD expression in HMEC under these cell culture conditions. EcSOD mRNA expression was strongly induced in the 2D-cultured HMEC after treatment with a DNA methyltransferase inhibitor. In addition, epigenetic analyses showed a decrease in the degree of CpG methylation in the EcSOD promoter in the 3D versus 2D-cultured HMEC. More importantly, >80% of clinical mammary adenocarcinoma samples showed significantly decreased EcSOD mRNA and protein expression levels compared with normal mammary tissues and there is an inverse correlation between the expression levels of EcSOD and the clinical stages of breast cancer. Combined bisulfite restriction analysis analysis of some of the tumors also revealed an association of DNA methylation with the loss of EcSOD expression in vivo. Furthermore, overexpression of EcSOD inhibited breast cancer metastasis in both the experimental lung metastasis model and the syngeneic mouse model. This study suggests that epigenetic silencing of EcSOD may contribute to mammary tumorigenesis and that restoring the extracellular superoxide scavenging

  2. Changes in mitochondrial DNA alter expression of nuclear encoded genes associated with tumorigenesis

    Energy Technology Data Exchange (ETDEWEB)

    Jandova, Jana; Janda, Jaroslav [Southern Arizona VA Healthcare System, Department of Medicine, Dermatology Division and Arizona Cancer Center, University of Arizona, 1515 N Campbell Avenue, Tucson, AZ 857 24 (United States); Sligh, James E, E-mail: jsligh@azcc.arizona.edu [Southern Arizona VA Healthcare System, Department of Medicine, Dermatology Division and Arizona Cancer Center, University of Arizona, 1515 N Campbell Avenue, Tucson, AZ 857 24 (United States)

    2012-10-15

    genes associated with tumorigenesis. Black-Right-Pointing-Pointer MMP-9 is up-regulated and Col1a1 is down-regulated in mutant cybrids. Black-Right-Pointing-Pointer GM6001 reduced the enhanced motility of mutant cybrids caused by up-regulated MMP-9. Black-Right-Pointing-Pointer The MMP-9 expression and invasiveness of mutant cybrids were reduced by Bay 11-7802.

  3. Modulatory effects of Azadirachta indica on benzo(a)pyrene-induced forestomach tumorigenesis in mice

    Institute of Scientific and Technical Information of China (English)

    Subhash Chander Gangar; Rajat Sandhir; Durg Vijay Rai; Ashwani Koul

    2006-01-01

    AIM: To evaluate the chemopreventive effects of aqueous Azadirachta indica (A indica) leaf extract (AAILE)against benzo(a)pyrene [B(a)P]-induced forestomach tumorigenesis in Balb/c mice.METHODS: Female Balb/c mice were divided into four groups of 10-12 animals each. For induction of forestomach tumors, starting from d 14 of the experiment, mice of B(a)P and B(a)P+A indica groups were given intra-gastric instillations of B(a)P (40 mg/kg), twice a week for four weeks. Mice of A indica and B(a)P+A indica groups were orally administered with AAILE (100mg/kg), two weeks prior to B(a)P instillations till the end of the experiment. After 22 wk of the first B(a)P instillation, mice were sacrificed and the forestomachs were analyzed for development of tumors, scanning electron microscopy (SEM) and histopathology.RESULTS: Tumor incidence was observed to be 100%in mice that received only B(a)P. However, treatment with AAILE reduced the tumor incidence by 58.4%as observed in mice of B(a)P+A indica group when compared to that of B(a)P group. Similarly, the tumor burden and multiplicity were seen to decrease by 87.3% and 69.6% respectively in mice of B(a)P+A indica group when compared to those of B(a)P group.Scanning electron microscopy analysis showed that AAILE treatment itself did not cause any abnormalities on the surface architecture of forestomach epithelium.In tumorous forestomach, surface disruption was observed. Over the forestomach tumors of B(a)P group of mice certain rounded structures were seen in addition to closely placed tongue-shaped squamous cells. Interestingly, these rounded structures were not observed in B(a)P + A indica group of mice.Histopathalogically, the tumors were identical and diagnosed to be papillomas. Mice from control and A indica groups of mice did not develop any forestomach tumors and showed normal histo-architecture.CONCLUSION: The present data suggest that A indica exerts chemopreventive effects against B(a)P-induced forestomach tumors in

  4. BTB-Zinc Finger Oncogenes Are Required for Ras and Notch-Driven Tumorigenesis in Drosophila.

    Directory of Open Access Journals (Sweden)

    Karen Doggett

    Full Text Available During tumorigenesis, pathways that promote the epithelial-to-mesenchymal transition (EMT can both facilitate metastasis and endow tumor cells with cancer stem cell properties. To gain a greater understanding of how these properties are interlinked in cancers we used Drosophila epithelial tumor models, which are driven by orthologues of human oncogenes (activated alleles of Ras and Notch in cooperation with the loss of the cell polarity regulator, scribbled (scrib. Within these tumors, both invasive, mesenchymal-like cell morphology and continual tumor overgrowth, are dependent upon Jun N-terminal kinase (JNK activity. To identify JNK-dependent changes within the tumors we used a comparative microarray analysis to define a JNK gene signature common to both Ras and Notch-driven tumors. Amongst the JNK-dependent changes was a significant enrichment for BTB-Zinc Finger (ZF domain genes, including chronologically inappropriate morphogenesis (chinmo. chinmo was upregulated by JNK within the tumors, and overexpression of chinmo with either RasV12 or Nintra was sufficient to promote JNK-independent epithelial tumor formation in the eye/antennal disc, and, in cooperation with RasV12, promote tumor formation in the adult midgut epithelium. Chinmo primes cells for oncogene-mediated transformation through blocking differentiation in the eye disc, and promoting an escargot-expressing stem or enteroblast cell state in the adult midgut. BTB-ZF genes are also required for Ras and Notch-driven overgrowth of scrib mutant tissue, since, although loss of chinmo alone did not significantly impede tumor development, when loss of chinmo was combined with loss of a functionally related BTB-ZF gene, abrupt, tumor overgrowth was significantly reduced. abrupt is not a JNK-induced gene, however, Abrupt is present in JNK-positive tumor cells, consistent with a JNK-associated oncogenic role. As some mammalian BTB-ZF proteins are also highly oncogenic, our work suggests that

  5. The effect of dietary zinc - and polyphenols intake on DMBA-induced mammary tumorigenesis in rats

    Directory of Open Access Journals (Sweden)

    Bobrowska-Korczak Barbara

    2012-04-01

    Full Text Available Abstract Background The aim of the study was to investigate the effect of dietary supplementation with zinc and polyphenol compounds, i.e. resveratrol and genistein, on the effectiveness of chemically induced mammary cancer and the changes in the content of selected elements (Zn, Cu, Mg, Fe, Ca in tumors as compared with normal tissue of the mammary gland. Methods Female Sprague-Dawley rats were divided into study groups which, apart from the standard diet and DMBA (7,12-dimethyl-1,2- benz[a]anthracene, were treated with zinc ions (Zn or zinc ions + resveratrol (Zn + resveratrol or zinc ions + genistein (Zn + genistein via gavage for a period from 40 days until 20 weeks of age. The ICP-OES (inductively coupled plasma optical emission spectrometry technique was used to analyze the following elements: magnesium, iron, zinc and calcium. Copper content in samples was estimated in an atomic absorption spectrophotometer. Results Regardless of the diet (standard; Zn; Zn + resveratrol; Zn + genistein, DMBA-induced breast carcinogenesis was not inhibited. On the contrary, in the Zn + resveratrol supplemented group, tumorigenesis developed at a considerably faster rate. On the basis of quantitative analysis of selected elements we found - irrespectively of the diet applied - great accumulation of copper and iron, which are strongly prooxidative, with a simultaneous considerable decrease of the magnesium content in DMBA-induced mammary tumors. The combination of zinc supplementation with resveratrol resulted in particularly large differences in the amount of the investigated elements in tumors as compared with their content in normal tissue. Conclusions Diet supplementation with zinc and polyphenol compounds, i.e. resveratrol and genistein had no effect on the decreased copper level in tumor tissue and inhibited mammary carcinogenesis in the rat. Irrespectively of the applied diet, the development of the neoplastic process in rats resulted in changes of

  6. The transcription factor ATF3 acts as an oncogene in mouse mammary tumorigenesis

    Directory of Open Access Journals (Sweden)

    Thames Howard D

    2008-09-01

    -expressing cells of the murine mammary gland results in the development of squamous metaplastic lesions in nulliparous females, and in mammary tumors in biparous mice, suggesting that ATF3 acts as a mammary oncogene. A subset of human breast tumors expresses high levels of ATF3, suggesting that ATF3 may play an oncogenic role in human breast tumorigenesis, and therefore may be useful as either a biomarker or therapeutic target.

  7. Alcoholic liver disease: The gut microbiome and liver crosstalk

    OpenAIRE

    Hartmann, Phillipp; Seebauer, Caroline T.; Schnabl, Bernd

    2015-01-01

    Alcoholic liver disease is a leading cause of morbidity and mortality worldwide. Alcoholic fatty liver disease can progress to steatohepatitis, alcoholic hepatitis, fibrosis, and cirrhosis. Patients with alcohol abuse show quantitative and qualitative changes in the composition of the intestinal microbiome. Furthermore, patients with alcoholic liver disease have increased intestinal permeability and elevated systemic levels of gut-derived microbial products. Maintaining eubiosis, stabilizing ...

  8. The Nlrp3 Inflammasome Suppresses Colorectal Cancer Metastatic Growth in the Liver by Promoting Natural Killer Cell Tumoricidal Activity.

    Science.gov (United States)

    Dupaul-Chicoine, Jeremy; Arabzadeh, Azadeh; Dagenais, Maryse; Douglas, Todd; Champagne, Claudia; Morizot, Alexandre; Rodrigue-Gervais, Ian Gaël; Breton, Valérie; Colpitts, Sara L; Beauchemin, Nicole; Saleh, Maya

    2015-10-20

    The crosstalk between inflammation and tumorigenesis is now clearly established. However, how inflammation is elicited in the metastatic environment and the corresponding contribution of innate immunity pathways in suppressing tumor growth at secondary sites are poorly understood. Here, we show that mice deficient in Nlrp3 inflammasome components had exacerbated liver colorectal cancer metastatic growth, which was mediated by impaired interleukin-18 (IL-18) signaling. Control of tumor growth was independent of differential cancer cell colonization or proliferation, intestinal microbiota effects, or tumoricidal activity by the adaptive immune system. Instead, the inflammasome-IL-18 pathway impacted maturation of hepatic NK cells, surface expression of the death ligand FasL, and capacity to kill FasL-sensitive tumors. Our results define a regulatory signaling circuit within the innate immune system linking inflammasome activation to effective NK-cell-mediated tumor attack required to suppress colorectal cancer growth in the liver. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Liver Disease and Pulmonary Hypertension

    Science.gov (United States)

    ... fats, produces several important com- pounds, stores certain vitamins, makes specific amino acids, converts glucose to glycogen, ... liver. This increased pres- sure causes blood to bypass the liver. As a result, the blood is ...

  10. Propylthiouracil for alcoholic liver disease

    DEFF Research Database (Denmark)

    Fede, Giuseppe; Germani, Giacomo; Gluud, Christian

    2011-01-01

    Randomised clinical trials have addressed the question whether propylthiouracil has any beneficial effects in patients with alcoholic liver disease.......Randomised clinical trials have addressed the question whether propylthiouracil has any beneficial effects in patients with alcoholic liver disease....

  11. Propylthiouracil for alcoholic liver disease

    DEFF Research Database (Denmark)

    Rambaldi, A; Gluud, C

    2005-01-01

    Randomised clinical trials have addressed the question whether propylthiouracil has any beneficial effects in patients with alcoholic liver disease.......Randomised clinical trials have addressed the question whether propylthiouracil has any beneficial effects in patients with alcoholic liver disease....

  12. Takotsubo cardiomyopathy post liver transplantation.

    Science.gov (United States)

    Vachiat, Ahmed; McCutcheon, Keir; Mahomed, Adam; Schleicher, Gunter; Brand, Liezl; Botha, Jean; Sussman, Martin; Manga, Pravin

    2016-10-23

    A patient with end-stage liver disease developed stress-induced Takotsubo cardiomyopathy post liver transplantation, with haemodynamic instability requiring a left ventricular assist device. We discuss the diagnosis and management of this condition.

  13. Ton That Tung's livers.

    Science.gov (United States)

    Helling, Thomas S; Azoulay, Daniel

    2014-06-01

    Born in the early 20th century, the Vietnamese surgeon Ton That Tung received his medical education in French colonial Indochina at the fledgling l'Ecole de Médecine de Hanoi, the first indigenous medical school in Southeast Asia. The benefactor of a postgraduate position at the medical school, Ton That Tung subsequently obtained his surgical training at the Phù Doãn Hospital in Hanoi and concurrently developed a passion for the study of liver anatomy, pathology, and surgery. His contributions to an understanding of liver anatomy based on meticulous dissection of autopsy specimens antedated and rivaled later work by the famous Western anatomists Couinaud, Healey, Schroy, and others. Ton That Tung's contributions, however, were overshadowed by the intense national struggles of the Vietnamese to establish independent rule and self-governance from the French and by eventual alignment with eastern bloc Communist countries, thus isolating much of his work behind the "Iron Curtain" until well after the end of the Cold War. Nevertheless, Ton That Tung remains a pioneer in liver anatomy and liver surgery. His commitment to surgical science and, more importantly, to the Vietnamese people stands as a tribute to the tireless pursuit of his ideals.

  14. LIVER AND BILIARY SYSTEM

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    12.1 Liver function2003091 Treatment of acute hepatic failure by transplantation of microencapsulated xenogenic hepatocyte.ZHANG Weijie(张伟杰), et al. Instit Organ Transplant, Tongji Hosp, Huazhong Univ Sci & Technol, Wuhan 430030. World Chin J Digestol 2002; 10 (12): 1396-1398.

  15. Nonalcoholic fatty liver disease

    DEFF Research Database (Denmark)

    Patrick-Melin, A J; Kalinski, M I; Kelly, K R

    2009-01-01

    that features steatosis plus inflammation, termed nonalcoholic steatohepatitis (NASH), which may in turn progress to hepatic fibrosis, cirrhosis, and sub-acute liver failure. Thus, NAFLD and its subsequent complications create a significant health burden, and currently there is no effective treatment strategy...

  16. Living Donor Liver Transplantation

    Science.gov (United States)

    ... be a husband or wife. What are Some Benefits of a Living-donor Liver Transplant? In the ... Not have a selfish motive for donating. Paid donation is illegal in the ... leave for being organ donors. Other employers have similar programs, so check ...

  17. Coffee and liver health.

    Science.gov (United States)

    Morisco, Filomena; Lembo, Vincenzo; Mazzone, Giovanna; Camera, Silvia; Caporaso, Nicola

    2014-01-01

    Coffee is one of the most widely used beverages in the world. It includes a wide array of components that can have potential implications for health. Several epidemiological studies associate coffee consumption with a reduced incidence of various chronic diseases such as diabetes, cardiovascular diseases, and neurodegenerative diseases. Over the past 20 years, an increasing number of epidemiological and experimental studies have demonstrated the positive effects of coffee on chronic liver diseases. Coffee consumption has been inversely associated with the activity of liver enzymes in subjects at risk, including heavy drinkers. Coffee favours an improvement in hepatic steatosis and fibrosis, and a reduction in cirrhosis and the risk of hepatocellular carcinoma. The mechanisms of action through which it exerts its beneficial effects are not fully understood. Experimental studies show that coffee consumption reduces fat accumulation and collagen deposition in the liver and promotes antioxidant capacity through an increase in glutathione as well as modulation of the gene and protein expression of several inflammatory mediators. Animal and in vitro studies indicate that cafestol and kahweol, 2 diterpens, can operate by modulating multiple enzymes involved in the detoxification process of carcinogens causing hepatocellular carcinoma. It is unclear whether the benefits are significant enough to "treat" patients with chronic liver disease. While we await clarification, moderate daily unsweetened coffee use is a reasonable adjuvant to therapy for these patients.

  18. Hypertension and liver disease

    DEFF Research Database (Denmark)

    Henriksen, Jens Henrik; Møller, Søren

    2004-01-01

    Arterial hypertension is a common disorder with a frequency of 10% to 15% in subjects in the 40- to 60-year age group. Yet most reports find the prevalence of arterial hypertension in patients with chronic liver disease (cirrhosis) much lower. In this review, we consider the alterations in systemic...

  19. Cirrhosis of the liver

    DEFF Research Database (Denmark)

    Bendtsen, Flemming; Larsen, Fin Stolze; Ott, Peter

    2014-01-01

    Cirrhosis of the liver is a frequent and dangerous disease that causes numerous clinical contacts due to its complications. Competent and fast clinical decisions are often necessary in the acute setting and a broad clinical approach for the long-term problems due to the co-morbidity. Danish...

  20. Angiogenesis and liver fibrosis

    Institute of Scientific and Technical Information of China (English)

    Gülsüm ?zlem Elpek

    2015-01-01

    Recent data indicate that hepatic angiogenesis,regardless of the etiology, takes place in chronic liverdiseases (CLDs) that are characterized by inflammationand progressive fibrosis. Because antiangiogenictherapy has been found to be efficient inthe prevention of fibrosis in experimental models ofCLDs, it is suggested that blocking angiogenesis couldbe a promising therapeutic option in patients withadvanced fibrosis. Consequently, efforts are beingdirected to revealing the mechanisms involved inangiogenesis during the progression of liver fibrosis.Literature evidences indicate that hepatic angiogenesisand fibrosis are closely related in both clinical andexperimental conditions. Hypoxia is a major inducer ofangiogenesis together with inflammation and hepaticstellate cells. These profibrogenic cells stand at theintersection between inflammation, angiogenesis andfibrosis and play also a pivotal role in angiogenesis.This review mainly focuses to give a clear view on therelevant features that communicate angiogenesis withprogression of fibrosis in CLDs towards the-end point ofcirrhosis that may be translated into future therapies.The pathogenesis of hepatic angiogenesis associatedwith portal hypertension, viral hepatitis, non-alcoholicfatty liver disease and alcoholic liver disease are alsodiscussed to emphasize the various mechanisms involvedin angiogenesis during liver fibrogenesis.

  1. Radioembolization of liver tumors

    NARCIS (Netherlands)

    van den Hoven, AF

    2016-01-01

    Radioembolization is a therapy during which radioactive microspheres are administered through a microcatheter placed in the hepatic arterial vasculature in order to irradiate liver tumors from within. In the past decennium, this treatment has evolved as a safe and effective treatment option for pati

  2. Propylthiouracil for alcoholic liver disease

    DEFF Research Database (Denmark)

    Rambaldi, A; Gluud, C

    2002-01-01

    Alcohol is the most common cause of liver disease in the Western world today. Randomised clinical trials have addressed the question whether propylthiouracil has any efficacy in patients with alcoholic liver disease.......Alcohol is the most common cause of liver disease in the Western world today. Randomised clinical trials have addressed the question whether propylthiouracil has any efficacy in patients with alcoholic liver disease....

  3. Bariatric Surgery and Liver Transplantation.

    Science.gov (United States)

    Suraweera, Duminda; Saab, Elena G; Choi, Gina; Saab, Sammy

    2017-03-01

    Obesity is an important public health and medical concern in the United States. The rate of obesity has steadily risen for the past several decades. Obesity is associated with the development of nonalcoholic steatohepatitis, which is one of the leading indications for liver transplantation. After liver transplantation, recipients tend to gain weight and develop recurrent fatty liver. Over time, recurrent fatty liver may impact patient and graft survival. A bariatric surgical approach may be beneficial in select patients.

  4. 25 Ways to Love Your Liver

    Science.gov (United States)

    ... Baby Boomers Get Tested Core Programs HE Webinar Disney 2014 5 Ways to Love Your Liver Liver ... Drive Away Liver Disease Liver Lowdown Aug 2013 Disney Marathon In The Field Healthy Foods Diet Recommendations ...

  5. Stem cells in liver disease

    NARCIS (Netherlands)

    Poll, D. van

    2008-01-01

    Failure of the liver, the largest vital organ in the body, unequivocally results in death. Hepatic failure most commonly evolves over a period of several years as a result of chronic liver disease, most often viral hepatitis or alcoholic liver damage. In rarer cases, the organ shuts down within

  6. [Local treatment of liver tumors

    DEFF Research Database (Denmark)

    Pless, T.K.; Skjoldbye, Bjørn Ole

    2008-01-01

    Local treatment of non-resectable liver tumors is common. This brief review describes the local treatment techniques used in Denmark. The techniques are evaluated according to the evidence in literature. The primary local treatment is Radiofrequency Ablation of both primary liver tumors and liver...

  7. Improved transvenous liver biopsy needle

    DEFF Research Database (Denmark)

    Henriksen, Jens Henrik Sahl; Matzen, P; Christoffersen, P

    1979-01-01

    A modified type of the standard transvenous cholangiography biopsy needle is described. The modified tranvenous liver biopsy needle caused only minimal artefactual changes of the liver biopsy specimens. The new type of biopsy needle is a modified Menghini needle. The conventional Menghini needle...... should be avoided for transvenous catheter biopsies because of risk of leaving catheter fragments in the liver....

  8. Pediatric obesity and the liver

    NARCIS (Netherlands)

    Koot, B.G.P.

    2014-01-01

    Non-alcoholic fatty liver disease (NAFLD) is a frequent complication of obesity. In some of those with NAFLD, the fat accumulation in the liver will cause inflammation and fibrosis and can ultimately cause liver failure. In addition, in adults it has been established that NAFLD increases the risk of

  9. Stem cells in liver disease

    NARCIS (Netherlands)

    Poll, D. van

    2008-01-01

    Failure of the liver, the largest vital organ in the body, unequivocally results in death. Hepatic failure most commonly evolves over a period of several years as a result of chronic liver disease, most often viral hepatitis or alcoholic liver damage. In rarer cases, the organ shuts down within week

  10. Acute fatty liver in pregnancy.

    NARCIS (Netherlands)

    Tan, A.; Krieken, J.H.J.M. van; Peters, W.H.M.; Steegers, E.A.P.

    2002-01-01

    When confronted with liver abnormalities during the third trimester of pregnancy, one should consider acute fatty liver of pregnancy. The differential diagnosis with (pre-)eclampsia and HELLP syndrome is sometimes difficult. In these cases a liver biopsy is helpful though rarely performed during pre

  11. Systemic abnormalities in liver disease

    Institute of Scientific and Technical Information of China (English)

    Masami Minemura; Kazuto Tajiri; Yukihiro Shimizu

    2009-01-01

    Systemic abnormalities often occur in patients with liver disease. In particular, cardiopulmonary or renal diseases accompanied by advanced liver disease can be serious and may determine the quality of life and prognosis of patients. Therefore, both hepatologists and non-hepatologists should pay attention to such abnormalities in the management of patients with liver diseases.

  12. Pediatric obesity and the liver

    NARCIS (Netherlands)

    Koot, B.G.P.

    2014-01-01

    Non-alcoholic fatty liver disease (NAFLD) is a frequent complication of obesity. In some of those with NAFLD, the fat accumulation in the liver will cause inflammation and fibrosis and can ultimately cause liver failure. In addition, in adults it has been established that NAFLD increases the risk of

  13. Research Progress of Liver Diseases

    Institute of Scientific and Technical Information of China (English)

    XU Lie-ming; JIA Ji-dong

    2005-01-01

    @@ Liver diseases are widespread in China.The disease mostly includes viral hepatitis,alcoholic or non alcoholic fatty degeneration or steatohepatitis, autoimmune liver disease,hepatic fibrosis/cirrhosis and hepatic cancer.The mechanism of most liver diseases was studied clearly in developed countries.

  14. Oxidative stress and inflammation in liver carcinogenesis

    Directory of Open Access Journals (Sweden)

    Natalia Olaya

    2007-02-01

    series of transcription factors. Moreover, in addition to direct production of ROS by these pathogens, liver infiltration by activated phagocytic cells provides an additional source of ROS production that promotes oxidative stress via interleukin or NO production that can damage proteins, lipids and DNA.

    Nuclear MSI was demonstrated first in familial hereditary colorectal cancer (HNPCC and then in sporadic cancers, primarily digestive tract cancers such as colorectal, gastric and pancreatic cancers.In HCC, although nuclear MSI has been shown in some studies (15,18, there is as yet no direct evidence of alteration of the MMR genes and the biological and the clinicopathological significance of the lowlevel MSI seen in HCC is unclear. MSI has also been shown to occur in inflammatory tissues such as chronic hepatitis and cirrhosis as well as in ulcerative colitis, chronic pancreatitis and in non digestive inflammatory diseases such as rheumatoid arthritis.

    Recently, the role of mitochondria in carcinogenesis has been under numerous investigation, in part because their prominent role in apoptosis, ROS production and other aspects of tumour biology. The mitochondrial genome is particularly susceptible to mutations because of the high level of ROS generation in this organelle, coupled with a relatively low level of DNA repair. Somatic mutations of mitochondrial DNA (mtDNA have been shown in HCC as was also observed MSI. These findings suggest a potential role for mitochondrial genome instability in the early steps of tumorigenesis.

    Ischemia-reperfusion injury can occur in several situations and is a major cause of cell damage during surgery. Cells and tissues subjected to hypoxia by prolonged ischemia become acidic

  15. The anabolic androgenic steroid nandrolone decanoate disrupts redox homeostasis in liver, heart and kidney of male Wistar rats.

    Directory of Open Access Journals (Sweden)

    Stephan P Frankenfeld

    Full Text Available The abuse of anabolic androgenic steroids (AAS may cause side effects in several tissues. Oxidative stress is linked to the pathophysiology of most of these alterations, being involved in fibrosis, cellular proliferation, tumorigenesis, amongst others. Thus, the aim of this study was to determine the impact of supraphysiological doses of nandrolone decanoate (DECA on the redox balance of liver, heart and kidney. Wistar male rats were treated with intramuscular injections of vehicle or DECA (1 mg.100 g(-1 body weight once a week for 8 weeks. The activity and mRNA levels of NADPH Oxidase (NOX, and the activity of catalase, glutathione peroxidase (GPx and total superoxide dismutase (SOD, as well as the reduced thiol and carbonyl residue proteins, were measured in liver, heart and kidney. DECA treatment increased NOX activity in heart and liver, but NOX2 mRNA levels were only increased in heart. Liver catalase and SOD activities were decreased in the DECA-treated group, but only catalase activity was decreased in the kidney. No differences were detected in GPx activity. Thiol residues were decreased in the liver and kidney of treated animals in comparison to the control group, while carbonyl residues were increased in the kidney after the treatment. Taken together, our results show that chronically administered DECA is able to disrupt the cellular redox balance, leading to an oxidative stress state.

  16. Experimental study of bioartificial liver with cultured human liver cells

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    AIM To establish an extracorporeal bioartificial liver support system (EBLSS) using cultured human liver cells and to study its support effect for fulminant hepatic failure (FHF).METHODS The liver support experiment of EBLSS consisting of aggregates cultured human liver cells, hollow fiber bioreactor, and circulation unit was carried out in dizhepatic dogs.RESULTS The viability of isolated hepatocytes and nonparenchymal liver cells reached 96%. These cells were successfully cultured as multicellular spheroids with synthetic technique. The typical morphological appearance was retained up to the end of the artificial liver experiment. Compared with the control dogs treated with EBLSS without liver cells, the survival time of artificial liver support dogs was significantly prolonged. The changes of blood pressure, heart rate and ECG were slow. Both serum ammonia and lactate levels were significantly lowered at the 3rd h and 5th h. In addition, a good viability of human liver cells was noted after 5 h experiment.CONCLUSION EBLSS playing a metabolic role of cultured human hepatocytes, is capable of compensating the function of the liver, and could provide effective artificial liver support and therapy for patients with FHF.

  17. RORγt(+) hematopoietic cells are necessary for tumor cell proliferation during colitis-associated tumorigenesis in mice.

    Science.gov (United States)

    Martin, Maria; Kesselring, Rebecca K; Saidou, Balam; Brunner, Stefan M; Schiechl, Gabriela; Mouris, Verena F; Wege, Anja K; Rümmele, Petra; Schlitt, Hans J; Geissler, Edward K; Fichtner-Feigl, Stefan

    2015-06-01

    Colorectal cancer (CRC) is one of the most common tumor entities. In patients with inflammatory bowel diseases, the development of colitis-associated colon cancer is considered a dangerous long-term complication. IL-17A and the transcription factor retinoic acid receptor-related orphan receptor γt (RORγt) play fundamental roles in the pathogenesis of inflammatory bowel diseases; in human studies, we detected a dense infiltration of RORγt-dependent CD4(+) IL17A(+) T helper (Th)17 cells in specimens of CRC, ulcerative colitis, and ulcerative colitis-associated colorectal cancer. However, the mechanistic role of RORγt(+) hematopoietic cells in colitis-associated tumorigenesis remains unclear. To investigate colitis-associated colon tumorigenesis, we conducted studies in the AOM+DSS mouse model that revealed the importance of RORγt for colon tumor progression. In the absence of RORγt-dependent Th17 lymphocytes, mice showed signs of intense chronic colitis, but developed significantly fewer macroscopic tumor nodules. The reduction of tumor development in RORγt(-/-) mice was not due to reduced colon tumor initiation. However, the proliferation rate of tumor cells was reduced in the absence of RORγt-dependent Th17 cells and tumor cells showed pronounced signs of senescence-associated epigenetic and lysosomal changes. These results indicate an important role for the immunological milieu in colitis-associated cancer, which is shaped in-part by RORγt-dependent Th17 lymphocytes that support CRC growth.

  18. Intracerebral Distribution of the Oncometabolite D-2-Hydroxyglutarate in Mice Bearing Mutant Isocitrate Dehydrogenase Brain Tumors: Implications for Tumorigenesis

    Directory of Open Access Journals (Sweden)

    Amanda Pickard

    2016-10-01

    Full Text Available The prevalence of mutant IDH1 brain tumors has generated significant efforts to understand the role of the mutated enzyme product D-2-hydroxyglutarate (D2HG, an oncometabolite, in tumorigenesis, as well as means to eliminate it. Glymphatic clearance was proposed as a pathway that could be manipulated to accelerate D2HG clearance and dictated the study design that consisted of two cohorts of mice bearing U87/mutant IDH1 intracerebral tumors who underwent two microdialysis – providing D2HG interstitial fluid concentrations - sampling periods of awake and asleep (activate glymphatic clearance in a crossover manner. Glymphatic clearance was found not to have a significant effect on D2HG brain tumor interstitial fluid concentrations that were 126.9 ± 74.8 µM awake and 117.6 ± 98.6 µM asleep. These concentrations, although low relative to total brain tumor concentrations of 6.8 ± 3.6 mM, were considered sufficient to be transported by interstitial fluid and taken up into normal cells to cause deleterious effects. A model of D2HG CNS distribution supported this contention and was further supported by in vitro studies that showed D2HG could interfere with immune cell function. The study provides insight into the compartmental distribution of D2HG in the brain wherein the interstitial fluid serves as a dynamic pathway for D2HG to enter normal cells and contribute to tumorigenesis.

  19. Maslinic Acid-Enriched Diet Decreases Intestinal Tumorigenesis in ApcMin/+ Mice through Transcriptomic and Metabolomic Reprogramming

    Science.gov (United States)

    Sánchez-Tena, Susana; Reyes-Zurita, Fernando J.; Díaz-Moralli, Santiago; Vinardell, Maria Pilar; Reed, Michelle; García-García, Francisco; Dopazo, Joaquín; Lupiáñez, José A.; Günther, Ulrich; Cascante, Marta

    2013-01-01

    Chemoprevention is a pragmatic approach to reduce the risk of colorectal cancer, one of the leading causes of cancer-related death in western countries. In this regard, maslinic acid (MA), a pentacyclic triterpene extracted from wax-like coatings of olives, is known to inhibit proliferation and induce apoptosis in colon cancer cell lines without affecting normal intestinal cells. The present study evaluated the chemopreventive efficacy and associated mechanisms of maslinic acid treatment on spontaneous intestinal tumorigenesis in ApcMin/+ mice. Twenty-two mice were randomized into 2 groups: control group and MA group, fed with a maslinic acid–supplemented diet for six weeks. MA treatment reduced total intestinal polyp formation by 45% (P<0.01). Putative molecular mechanisms associated with suppressing intestinal polyposis in ApcMin/+ mice were investigated by comparing microarray expression profiles of MA-treated and control mice and by analyzing the serum metabolic profile using NMR techniques. The different expression phenotype induced by MA suggested that it exerts its chemopreventive action mainly by inhibiting cell-survival signaling and inflammation. These changes eventually induce G1-phase cell cycle arrest and apoptosis. Moreover, the metabolic changes induced by MA treatment were associated with a protective profile against intestinal tumorigenesis. These results show the efficacy and underlying mechanisms of MA against intestinal tumor development in the ApcMin/+ mice model, suggesting its chemopreventive potential against colorectal cancer. PMID:23527181

  20. Cytochrome P450 1B1 expression in rat esophageal tumorigenesis promoted by gastric and duodenal reflux.

    Science.gov (United States)

    Devlin, Andrea H; McIlroy, Marie; McKeen, Hayley D; Bonde, Pramode; Menezes, A A Carlos; Swarbrick, Christine J; Robson, Tracy; Hirst, David G; Campbell, F Charles; McGuigan, James A; McKeown, Stephanie R

    2009-02-01

    Cytochrome P450 1B1 (CYP1B1) mRNA is constitutively expressed in most normal extra-hepatic tissues; however the protein is not detectable in these tissues but is expressed in a wide variety of tumors. CYP1B1 is responsible for the activation of a number of carcinogens present in tobacco smoke and food. A surgical model of rat esophageal tumorigenesis, promoted by gastric or duodenal reflux was used to determine CYP1B1 expression in premalignant esophageal tissue. Immunohistochemistry was performed using a modified amplified fluorescein tyramide protocol. CYP1B1 was not observed in normal esophageal mucosa, submucosa, or muscularis mucosa. Animals exposed to gastric reflux developed mild hyperplasia. Varying degrees of hyperplasia were observed in the duodenal reflux group. All regions of hyperplasia showed moderate or strong CYP1B1 immunoreactivity. Duodenal reflux induced a small number of premalignant changes: immunoreactivity was absent from the epithelium of squamous dysplasia (0/10), Barrett's esophagus (0/7), and majority of dysplastic Barrett's esophagus (1/4). Moderate or strong immunoreactivity was observed in the majority (7/8) of squamous cell carcinomas (SCCs) in situ. Immunoreactivity was also observed in the lamina propria and submucosa in association with inflammation, regardless of the severity of inflammation. The expression of CYP1B1 in hyperplasia, SCCs in situ, or in association with inflammation may increase the production of carcinogenic metabolites, which may promote esophageal tumorigenesis.