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2.
Ann Oncol ; 31(2): 266-273, 2020 02.
Article de Anglais | MEDLINE | ID: mdl-31959343

RÉSUMÉ

BACKGROUND: The mouse strains usually used to generate patient-derived xenografts (PDXs) are immunocompromised, rendering them unsuitable for immunotherapy studies. Here we assessed the value of immune-PDX mouse models for predicting responses to anti-PD-1 checkpoint inhibitor therapy in patients. PATIENTS AND METHODS: Melanoma biopsies contained in a retrospective biobank were transplanted into NOG mice or NOG mice expressing interleukin 2 (hIL2-NOG mice). Tumor growth was monitored, and comparisons were made with clinical data, sequencing data, and current in silico predictive tools. RESULTS: Biopsies grew readily in NOG mice but growth was heterogeneous in hIL2-NOG mice. IL2 appears to activate T-cell immunity in the biopsies to block tumor growth. Biopsy growth in hIL2-NOG mice was negatively associated with survival in patients previously treated with PD-1 checkpoint blockade. In two cases, the prospective clinical decisions of anti-PD-1 therapy or targeted BRAF/MEK inhibitors were supported by the observed responses in mice. CONCLUSIONS: Immune-PDX models represent a promising addition to future biomarker discovery studies and for clinical decision making in patients receiving immunotherapy.


Sujet(s)
Mélanome , Animaux , Prise de décision clinique , Hétérogreffes , Humains , Mélanome/traitement médicamenteux , Mélanome/génétique , Souris , Souris de lignée NOD , Souris knockout , Souris SCID , Études prospectives , Études rétrospectives , Tests d'activité antitumorale sur modèle de xénogreffe
3.
Ann Oncol ; 29(2): 472-483, 2018 02 01.
Article de Anglais | MEDLINE | ID: mdl-29244072

RÉSUMÉ

Background: Smoking has been associated with colorectal cancer (CRC) incidence and mortality in previous studies and might also be associated with prognosis after CRC diagnosis. However, current evidence on smoking in association with CRC prognosis is limited. Patients and methods: For this individual patient data meta-analysis, sociodemographic and smoking behavior information of 12 414 incident CRC patients (median age at diagnosis: 64.3 years), recruited within 14 prospective cohort studies among previously cancer-free adults, was collected at baseline and harmonized across studies. Vital status and causes of death were collected for a mean follow-up time of 5.1 years following cancer diagnosis. Associations of smoking behavior with overall and CRC-specific survival were evaluated using Cox regression and standard meta-analysis methodology. Results: A total of 5229 participants died, 3194 from CRC. Cox regression revealed significant associations between former [hazard ratio (HR) = 1.12; 95 % confidence interval (CI) = 1.04-1.20] and current smoking (HR = 1.29; 95% CI = 1.04-1.60) and poorer overall survival compared with never smoking. Compared with current smoking, smoking cessation was associated with improved overall (HR<10 years = 0.78; 95% CI = 0.69-0.88; HR≥10 years = 0.78; 95% CI = 0.63-0.97) and CRC-specific survival (HR≥10 years = 0.76; 95% CI = 0.67-0.85). Conclusion: In this large meta-analysis including primary data of incident CRC patients from 14 prospective cohort studies on the association between smoking and CRC prognosis, former and current smoking were associated with poorer CRC prognosis compared with never smoking. Smoking cessation was associated with improved survival when compared with current smokers. Future studies should further quantify the benefits of nonsmoking, both for cancer prevention and for improving survival among CRC patients, in particular also in terms of treatment response.


Sujet(s)
Tumeurs colorectales/mortalité , Fumer/effets indésirables , Sujet âgé , Femelle , Humains , Mâle , Adulte d'âge moyen , Pronostic , Arrêter de fumer
4.
Eur J Clin Nutr ; 71(3): 407-419, 2017 03.
Article de Anglais | MEDLINE | ID: mdl-27966568

RÉSUMÉ

BACKGROUND/OBJECTIVES: To compare macronutrient intakes out of home-by location-to those at home and to investigate differences in total daily intakes between individuals consuming more than half of their daily energy out of home and those eating only at home. SUBJECTS/METHODS: Data collected through 24-h recalls or diaries among 23 766 European adults. Participants were grouped as 'non-substantial', 'intermediate' and 'very substantial out-of-home' eaters based on energy intake out of home. Mean macronutrient intakes were estimated at home and out of home (overall, at restaurants, at work). Study/cohort-specific mean differences in total intakes between the 'very substantial out-of-home' and the 'at-home' eaters were estimated through linear regression and pooled estimates were derived. RESULTS: At restaurants, men consumed 29% of their energy as fat, 15% as protein, 45% as carbohydrates and 11% as alcohol. Among women, fat contributed 33% of energy intake at restaurants, protein 16%, carbohydrates 45% and alcohol 6%. When eating at work, both sexes reported 30% of energy from fat and 55% from carbohydrates. Intakes at home were higher in fat and lower in carbohydrates and alcohol. Total daily intakes of the 'very substantial out-of-home' eaters were generally similar to those of individuals eating only at home, apart from lower carbohydrate and higher alcohol intakes among individuals eating at restaurants. CONCLUSIONS: In a large population of adults from 11 European countries, eating at work was generally similar to eating at home. Alcoholic drinks were the primary contributors of higher daily energy intakes among individuals eating substantially at restaurants.


Sujet(s)
Consommation alimentaire , Comportement alimentaire , Restaurants , Adulte , Consommation d'alcool , Régime alimentaire , Journaux alimentaires , Enquêtes sur le régime alimentaire , Hydrates de carbone alimentaires/administration et posologie , Hydrates de carbone alimentaires/analyse , Matières grasses alimentaires/administration et posologie , Matières grasses alimentaires/analyse , Protéines alimentaires/administration et posologie , Protéines alimentaires/analyse , Ration calorique , Europe , Femelle , Humains , Modèles linéaires , Mâle , Rappel mnésique , Facteurs sexuels
5.
Oncogene ; 35(36): 4689-97, 2016 09 08.
Article de Anglais | MEDLINE | ID: mdl-26804177

RÉSUMÉ

Inhibiting the bromodomain and extra-terminal (BET) domain family of epigenetic reader proteins has been shown to have potent anti-tumoral activity, which is commonly attributed to suppression of transcription. In this study, we show that two structurally distinct BET inhibitors (BETi) interfere with replication and cell cycle progression of murine Myc-induced lymphoma cells at sub-lethal concentrations when the transcriptome remains largely unaltered. This inhibition of replication coincides with a DNA-damage response and enhanced sensitivity to inhibitors of the upstream replication stress sensor ATR in vitro and in mouse models of B-cell lymphoma. Mechanistically, ATR and BETi combination therapy cause robust transcriptional changes of genes involved in cell death, senescence-associated secretory pathway, NFkB signaling and ER stress. Our data reveal that BETi can potentiate the cell stress and death caused by ATR inhibitors. This suggests that ATRi can be used in combination therapies of lymphomas without the use of genotoxic drugs.


Sujet(s)
Lymphomes/traitement médicamenteux , Protéines nucléaires/antagonistes et inhibiteurs , Protéines proto-oncogènes c-myc/génétique , Bibliothèques de petites molécules/administration et posologie , Animaux , Apoptose/effets des médicaments et des substances chimiques , Protéines mutées dans l'ataxie-télangiectasie/antagonistes et inhibiteurs , Protéines mutées dans l'ataxie-télangiectasie/génétique , Lignée cellulaire tumorale , Prolifération cellulaire/effets des médicaments et des substances chimiques , Vieillissement de la cellule/effets des médicaments et des substances chimiques , Altération de l'ADN/effets des médicaments et des substances chimiques , Stress du réticulum endoplasmique/effets des médicaments et des substances chimiques , Régulation de l'expression des gènes tumoraux/effets des médicaments et des substances chimiques , Histone acetyltransferases , Chaperons d'histones , Humains , Lymphomes/génétique , Lymphomes/anatomopathologie , Souris , Protéines nucléaires/génétique , Transduction du signal
6.
Int J Tuberc Lung Dis ; 19(9): 1068-72, 2015 Sep.
Article de Anglais | MEDLINE | ID: mdl-26260826

RÉSUMÉ

SETTING: Hanoi Lung Hospital, Hanoi, Viet Nam. OBJECTIVE: To compare the accuracy of CellScopeTB, a manually operated mobile digital fluorescence microscope, with conventional microscopy techniques. DESIGN: Patients referred for sputum smear microscopy to the Hanoi Lung Hospital from May to September 2013 were included. Ziehl-Neelsen (ZN) smear microscopy, conventional light-emitting diode (LED) fluorescence microscopy (FM), CellScopeTB-based LED FM and Xpert(®) MTB/RIF were performed on sputum samples. The sensitivity and specificity of microscopy techniques were determined in reference to Xpert results, and differences were compared using McNemar's paired test of proportions. RESULTS: Of 326 patients enrolled, 93 (28.5%) were Xpert-positive for TB. The sensitivity of ZN microscopy, conventional LED FM, and CellScopeTB-based LED FM was respectively 37.6% (95%CI 27.8-48.3), 41.9% (95%CI 31.8-52.6), and 35.5% (95%CI 25.8-46.1). The sensitivity of CellScopeTB was similar to that of conventional LED FM (difference -6.5%, 95%CI -18.2 to 5.3, P = 0.33) and ZN microscopy (difference -2.2%, 95%CI -9.2 to 4.9, P = 0.73). The specificity was >99% for all three techniques. DISCUSSION: CellScopeTB performed similarly to conventional microscopy techniques in the hands of experienced TB microscopists. However, the sensitivity of all sputum microscopy techniques was low. Options enabled by digital microscopy, such as automated imaging with real-time computerized analysis, should be explored to increase sensitivity.


Sujet(s)
Techniques bactériologiques/instrumentation , Microscopie de fluorescence/instrumentation , Expectoration/microbiologie , Tuberculose pulmonaire/diagnostic , Adulte , Femelle , Humains , Mâle , Adulte d'âge moyen , Mycobacterium tuberculosis , Sensibilité et spécificité , Vietnam
7.
Br J Cancer ; 112(7): 1273-82, 2015 Mar 31.
Article de Anglais | MEDLINE | ID: mdl-25742480

RÉSUMÉ

BACKGROUND: Vegetable and/or fruit intakes in association with hepatocellular carcinoma (HCC) risk have been investigated in case-control studies conducted in specific European countries and cohort studies conducted in Asia, with inconclusive results. No multi-centre European cohort has investigated the indicated associations. METHODS: In 486,799 men/women from the European Prospective Investigation into Cancer and nutrition, we identified 201 HCC cases after 11 years median follow-up. We calculated adjusted hazard ratios (HRs) for HCC incidence for sex-specific quintiles and per 100 g d(-1) increments of vegetable/fruit intakes. RESULTS: Higher vegetable intake was associated with a statistically significant, monotonic reduction of HCC risk: HR (100 g d(-1) increment): 0.83; 95% CI: 0.71-0.98. This association was consistent in sensitivity analyses with no apparent heterogeneity across strata of HCC risk factors. Fruit intake was not associated with HCC incidence: HR (100 g d(-1) increment): 1.01; 95% CI: 0.92-1.11. CONCLUSIONS: Vegetable, but not fruit, intake is associated with lower HCC risk with no evidence for heterogeneity of this association in strata of important HCC risk factors. Mechanistic studies should clarify pathways underlying this association. Given that HCC prognosis is poor and that vegetables are practically universally accessible, our results may be important, especially for those at high risk for the disease.


Sujet(s)
Carcinome hépatocellulaire/épidémiologie , Régime alimentaire/statistiques et données numériques , Tumeurs du foie/épidémiologie , Sujet âgé , Carcinome hépatocellulaire/étiologie , Études cas-témoins , Études de cohortes , Europe/épidémiologie , Femelle , Fruit , Humains , Tumeurs du foie/étiologie , Mâle , Adulte d'âge moyen , Facteurs de risque , Légumes
8.
Br J Cancer ; 111(9): 1870-80, 2014 Oct 28.
Article de Anglais | MEDLINE | ID: mdl-25121955

RÉSUMÉ

BACKGROUND: There is growing evidence of the protective role of dietary intake of flavonoids and lignans on cancer, but the association with bladder cancer has not been thoroughly investigated in epidemiological studies. We evaluated the association between dietary intakes of total and subclasses of flavonoids and lignans and risk of bladder cancer and its main morphological type, urothelial cell carcinoma (UCC), within the European Prospective Investigation into Cancer and Nutrition (EPIC) study. METHODS: A cohort of 477 312 men and women mostly aged 35-70 years, were recruited in 10 European countries. At baseline, dietary flavonoid and lignan intakes were estimated using centre-specific validated questionnaires and a food composition database based on the Phenol-Explorer, the UK Food Standards Agency and the US Department of Agriculture databases. RESULTS: During an average of 11 years of follow-up, 1575 new cases of primary bladder cancer were identified, of which 1425 were UCC (classified into aggressive (n=430) and non-aggressive (n=413) UCC). No association was found between total flavonoid intake and bladder cancer risk. Among flavonoid subclasses, significant inverse associations with bladder cancer risk were found for intakes of flavonol (hazard ratio comparing fifth with first quintile (HRQ5-Q1) 0.74, 95% confidence interval (CI): 0.61-0.91; P-trend=0.009) and lignans (HRQ5-Q1 0.78, 95% CI: 0.62-0.96; P-trend=0.046). Similar results were observed for overall UCC and aggressive UCC, but not for non-aggressive UCC. CONCLUSIONS: Our study suggests an inverse association between the dietary intakes of flavonols and lignans and risk of bladder cancer, particularly aggressive UCC.


Sujet(s)
Épithélioma in situ/épidémiologie , Régime alimentaire , Flavonoïdes , Lignanes , Tumeurs de la vessie urinaire/épidémiologie , Adulte , Sujet âgé , Épithélioma in situ/étiologie , Épithélioma in situ/prévention et contrôle , Europe/épidémiologie , Femelle , Études de suivi , Humains , Incidence , Mode de vie , Mâle , Adulte d'âge moyen , Évaluation de l'état nutritionnel , Pronostic , Études prospectives , Facteurs de risque , Tumeurs de la vessie urinaire/étiologie , Tumeurs de la vessie urinaire/prévention et contrôle
9.
Int J Cancer ; 134(10): 2504-11, 2014 May 15.
Article de Anglais | MEDLINE | ID: mdl-24226765

RÉSUMÉ

There is growing evidence of the protective role of the Mediterranean diet (MD) on cancer. However, to date no epidemiological study has investigated the influence of the MD on bladder cancer. We evaluated the association between adherence to the MD and risk of urothelial cell bladder cancer (UCC), according to tumor aggressiveness, in the European Prospective Investigation into Cancer and Nutrition (EPIC). The analysis included 477,312 participants, recruited from ten European countries between 1991 and 2000. Information from validated dietary questionnaires was used to develop a relative Mediterranean diet score (rMED), including nine dietary components. Cox regression models were used to assess the effect of the rMED on UCC risk, while adjusting for dietary energy and tobacco smoking of any kind. Stratified analyses were performed by sex, BMI, smoking status, European region and age at diagnosis. During an average follow-up of 11 years, 1,425 participants (70.9% male) were diagnosed with a first primary UCC. There was a negative but non-significant association between a high versus low rMED score and risk of UCC overall (HR: 0.84 [95% CI 0.69, 1.03]) and risk of aggressive (HR: 0.88 [95% CI 0.61, 1.28]) and non-aggressive tumors (HR: 0.78 [95% CI 0.54, 1.14]). Although there was no effect modification in the stratified analyses, there was a significant 34% (p = 0.043) decreased risk of UCC in current smokers with a high rMED score. In EPIC, the MD was not significantly associated with risk of UCC, although we cannot exclude that a MD may reduce risk in current smokers.


Sujet(s)
Carcinome transitionnel/épidémiologie , Régime méditerranéen , Tumeurs de la vessie urinaire/épidémiologie , Sujet âgé , Indice de masse corporelle , Enquêtes sur le régime alimentaire/méthodes , Enquêtes sur le régime alimentaire/statistiques et données numériques , Europe/épidémiologie , Femelle , Préférences alimentaires , Humains , Mâle , Adulte d'âge moyen , /méthodes , /statistiques et données numériques , Modèles des risques proportionnels , Études prospectives , Appréciation des risques/méthodes , Appréciation des risques/statistiques et données numériques , Facteurs de risque , Fumer , Enquêtes et questionnaires , Facteurs temps
10.
Oncogenesis ; 2: e44, 2013 Apr 15.
Article de Anglais | MEDLINE | ID: mdl-23588493

RÉSUMÉ

Cancer development occurs in response to the successive accumulation of mutations that eventually targets key regulators of cell proliferation. As most mutations likely occur randomly, cancer driver mutations can only be found if they are recurrent. Here we use exome sequencing of the mouse cell lines Panc02, L1210 and Colon 26 to identify genetic alterations (single-nucleotide polymorphisms and small insertion and deletions) that occurred in three different strains of mice and that resulted in tumorigenesis. We identify known mutations in genes like Kras, Cdkn2a/b, Smad4 and Trp53 and a large list of genes whose causal link to cancer is unknown. Interestingly, by screening a compound library we find that the identified oncogenic Kras mutation in Colon 26 cells correlates with its sensitivity to MEK inhibitors in vitro and in vivo. Our analysis of these mouse tumor exomes show that their manageable number of mutations could facilitate the identification of novel mutations or pathways driving tumor development. Furthermore, their use as tools is now enhanced as they can be used to create syngenic transplant models for utilization in drug discovery and validation. Finally, by showing that Kras mutant Colon 26 cells are sensitive to MEK inhibitors, we provide one proof-of-principle experiment that a platform containing targeted resequencing and drug screens could be a valuable addition in the clinic to devise anti-cancer drug schemes.

11.
Eur J Clin Nutr ; 66(8): 957-63, 2012 Aug.
Article de Anglais | MEDLINE | ID: mdl-22669330

RÉSUMÉ

BACKGROUND/OBJECTIVES: Cross-sectionally, educational attainment is strongly associated with the prevalence of obesity, but this association is less clear for weight change during adult life. The objective of this study is to examine the association between educational attainment and weight change during adult life in the European Prospective Investigation into Cancer and Nutrition (EPIC). SUBJECTS/METHODS: EPIC is a cohort study with 361,467 participants and up to 10 years of follow-up. Educational attainment was categorized according to the highest obtained school level (primary school or less, vocational secondary training, other secondary education and university). Multivariate mixed-effects linear regression models were used to study education in relation to weight at age 20 years (self-reported), to annual change in weight between age 20 years and measured weight at recruitment, and to annual change in weight during follow-up time. RESULTS: Higher educational attainment was associated with on average a lower body mass index (BMI) at age 20 years and a lower increase in weight up to recruitment (highest vs lowest educational attainment in men: -60 g per year (95% confidence interval (CI) -80; -40), women -110 g per year (95% CI -130; -80)). Although during follow-up after recruitment an increase in body weight was observed in all educational levels, gain was lowest in men and women with a university degree (high vs low education -120 g per year (95% CI -150; -90) and -70 g per year (95% CI -90; -60), respectively). CONCLUSIONS: Existing differences in BMI between higher and lower educated individuals at early adulthood became more pronounced during lifetime, which possibly impacts on obesity-related chronic disease risk in persons with lower educational attainment.


Sujet(s)
Poids , Niveau d'instruction , Obésité/épidémiologie , Adulte , Indice de masse corporelle , Maladie chronique , Études de cohortes , Études transversales , Ration calorique , Europe/épidémiologie , Femelle , Études de suivi , Humains , Mode de vie , Modèles linéaires , Mâle , Adulte d'âge moyen , État nutritionnel , Prévalence , Facteurs de risque , Enquêtes et questionnaires
12.
Eur J Clin Nutr ; 66(6): 694-700, 2012 Jun.
Article de Anglais | MEDLINE | ID: mdl-22333874

RÉSUMÉ

BACKGROUND/OBJECTIVE: Long-term effects of carbohydrate-restricted diets are unclear. We examined a low-carbohydrate, high-protein (LCHP) score in relation to mortality. SUBJECTS/METHODS: This is a population-based cohort study on adults in the northern Swedish county of Västerbotten. In 37,639 men (1460 deaths) and 39,680 women (923 deaths) from the population-based Västerbotten Intervention Program, deciles of energy-adjusted carbohydrate (descending) and protein (ascending) intake were added to create an LCHP score (2-20 points). Sex-specific hazard ratios (HR) were calculated by Cox regression. RESULTS: Median intakes of carbohydrates, protein and fat in subjects with LCHP scores 2-20 ranged from 61.0% to 38.6%, 11.3% to 19.2% and 26.6% to 41.5% of total energy intake, respectively. High LCHP score (14-20 points) did not predict all-cause mortality compared with low LCHP score (2-8 points), after accounting for saturated fat intake and established risk factors (men: HR for high vs low 1.03 (95% confidence interval (CI) 0.88-1.20), P for continuous = 0.721; women: HR for high vs low 1.10 (95% CI 0.91-1.32), P for continuous = 0.229). For cancer and cardiovascular disease, no clear associations were found. Carbohydrate intake was inversely associated with all-cause mortality, though only statistically significant in women (multivariate HR per decile increase 0.95 (95% CI 0.91-0.99), P = 0.010). CONCLUSION: Our results do not support a clear, general association between LCHP score and mortality. Studies encompassing a wider range of macronutrient consumption may be necessary to detect such an association.


Sujet(s)
Cause de décès , Régime pauvre en glucides , Hydrates de carbone alimentaires/pharmacologie , Protéines alimentaires/pharmacologie , Ration calorique , Adulte , Maladies cardiovasculaires/mortalité , Études de cohortes , Matières grasses alimentaires/administration et posologie , Femelle , Humains , Mâle , Adulte d'âge moyen , Tumeurs/mortalité , Modèles des risques proportionnels , Facteurs de risque , Suède/épidémiologie
13.
Nutr Metab Cardiovasc Dis ; 20(7): 527-35, 2010 Sep.
Article de Anglais | MEDLINE | ID: mdl-19695858

RÉSUMÉ

BACKGROUND AND AIM: In northern Sweden, consumption of both filtered and boiled coffee is common. Boiled coffee, especially popular in rural areas, is known to raise blood lipids, a risk factor for acute myocardial infarction (MI). To our knowledge, only one epidemiological study, a case-control study from Sweden, has investigated boiled coffee in MI, noting an increased risk at high consumption levels in men, and no association in women. The aim of the present nested case-referent study was to relate consumption of filtered and boiled coffee to the risk of first MI. METHODS AND RESULTS: The study subjects were 375 cases (303 men, 72 women) and 1293 matched referents from the population-based Northern Sweden Health and Disease Study. Coffee consumption was assessed by food frequency questionnaire. Risk estimates were calculated by conditional logistic regression. A statistically significant positive association was found between consumption of filtered coffee and MI risk in men [odds ratio for consumption > or = 4 times/day versus < or = 1 time/day 1.73 (95% CI 1.05-2.84)]. In women, a similar association was observed, but for boiled coffee [odds ratio 2.51 (95% CI 1.08-5.86)]. After adjustment for current smoking, postsecondary education, hypertension, and sedentary lifestyle, the results for women were no longer statistically significant. CONCLUSION: Consumption of filtered coffee was positively associated with the risk of a first MI in men. A similar tendency was observed for boiled coffee in women, but the result was not statistically significant in multivariate analysis. Further investigation in a larger study is warranted.


Sujet(s)
Café/effets indésirables , Infarctus du myocarde/étiologie , Études cas-témoins , Femelle , Filtration , Humains , Modèles logistiques , Mâle , Adulte d'âge moyen , Odds ratio , Appréciation des risques , Facteurs de risque , Facteurs sexuels , Enquêtes et questionnaires , Suède
14.
Biochem Biophys Res Commun ; 357(3): 707-11, 2007 Jun 08.
Article de Anglais | MEDLINE | ID: mdl-17448444

RÉSUMÉ

Modulation of bile acid synthesis in human by cholestyramine or by chenodeoxycholic acid (CDCA) treatment affects lipoprotein metabolism leading to altered plasma lipid levels. The molecular changes caused by these treatments, which in turn influence lipoprotein metabolism, are still not entirely known in humans. In this study, mRNA levels were analyzed using real time RT-PCR in liver tissue from patients undergoing cholecystectomy due to gallstone disease. The patients were treated with either CDCA (n=6) or cholestyramine (n=5) for three weeks prior to surgery, six patients received no treatment and served as controls. Cholestyramine increased the expression of the LDL receptor (LDLR) by about 65% and that of proprotein convertase subtilisin kexin 9 (PCSK9) by 70%. After CDCA the levels of both LDLR and hydroxy-methyl-glutaryl coenzyme A reductase mRNA decreased approximately by 50%. The expression of PCSK9 was not changed. The mRNA levels of PCSK9, LDLR, and HMGCoAR were significantly correlated to those of sterol regulatory element binding protein 2 (SREBP2), indicating that SREBP2 is of importance in the regulation of the expression of these genes also in human liver.


Sujet(s)
Acides et sels biliaires/métabolisme , Chénodiol/pharmacologie , Résine de cholestyramine/pharmacologie , Lipoprotéines/métabolisme , Foie/effets des médicaments et des substances chimiques , Membre-1 de la sous-famille A des transporteurs à cassette liant l'ATP , Transporteurs ABC/génétique , Adulte , Sujet âgé , Anticholestérolémiants/pharmacologie , Anticholestérolémiants/usage thérapeutique , Apolipoprotéine A-I/génétique , Chénodiol/usage thérapeutique , Cholécystectomie , Résine de cholestyramine/usage thérapeutique , Femelle , Calculs biliaires/traitement médicamenteux , Calculs biliaires/génétique , Calculs biliaires/métabolisme , Agents gastro-intestinaux/pharmacologie , Agents gastro-intestinaux/usage thérapeutique , Régulation de l'expression des gènes/effets des médicaments et des substances chimiques , Humains , Hydroxymethylglutaryl-CoA reductases/génétique , Foie/métabolisme , Mâle , Adulte d'âge moyen , Proprotéine convertase 9 , Proprotein convertases , Isoformes de protéines/génétique , ARN messager/génétique , ARN messager/métabolisme , Récepteurs aux lipoprotéines LDL/génétique , RT-PCR , Serine endopeptidases/génétique , Protéine-2 de liaison à l'élément de régulation des stérols/génétique
15.
Oncogene ; 26(20): 2833-9, 2007 May 03.
Article de Anglais | MEDLINE | ID: mdl-17099725

RÉSUMÉ

p18(Ink4c) functions as a dedicated inhibitor of cyclin-D-dependent kinases. Loss of Ink4c predisposes mice to tumor development and, in a dose-dependent manner, complements the tumor-promoting effects of various oncogenes. We have now addressed whether Ink4c loss impacts B-cell tumor development in the Emu-Myc transgenic mouse, a model of human Burkitt lymphoma. Loss of one or both alleles did not influence the onset of lymphoma in Emu-Myc transgenics, and did not appreciably affect Myc's proliferative or apoptotic responses in precancerous B cells. Nevertheless, Ink4c loss modulated the effects of Myc-induced transformation by decreasing the frequency of Arf loss, an ordinarily common event in Emu-Myc-induced lymphomas.


Sujet(s)
Inhibiteur p18 de kinase cycline-dépendante/physiologie , Lymphome B/génétique , Lymphome B/prévention et contrôle , Protéines proto-oncogènes c-myc/physiologie , Animaux , Apoptose/génétique , Prolifération cellulaire , Inhibiteur p16 de kinase cycline-dépendante/génétique , Inhibiteur p18 de kinase cycline-dépendante/génétique , Évolution de la maladie , Régulation de l'expression des gènes tumoraux , Gènes de chaine lourde d'immunoglobuline , Lymphome B/anatomopathologie , Souris , Souris de lignée C57BL , Souris transgéniques , Protéines de fusion oncogènes/génétique , Protéines de fusion oncogènes/physiologie , Protéines proto-oncogènes c-myc/génétique
16.
J Med Chem ; 32(6): 1217-30, 1989 Jun.
Article de Anglais | MEDLINE | ID: mdl-2724295

RÉSUMÉ

Eighty-four analogues and derivatives of the acetylcholine-storage-blocking drug trans-2-(4-phenylpiperidino)-cyclohexanol (vesamicol) were synthesized, and their potencies were evaluated with the acetylcholine active-transport assay utilizing purified synaptic vesicles from Torpedo electric organ. The parent drug exhibits enantioselectivity, with (-)-vesamicol being 25-fold more potent than (+)-vesamicol. The atomic structure and absolute configuration of (+)-vesamicol were determined by X-ray crystallography. The absolute configuration of (-)-vesamicol is 1R,2R. Structure-activity evidence indicates that (-)-vesamicol does not act as an acetylcholine analogue. Alterations to all three rings can have large effects on potency. Unexpectedly, analogues locking the alcohol and ammonium groups trans-diequatorial or trans-diaxial both exhibit good potency. A potent benzovesamicol family has been discovered that is suitable for facile elaboration of the sort useful in affinity labeling and affinity chromatography applications. A good correlation was found between potencies as assessed by the acetylcholine transport assay and LD50 values in mouse.


Sujet(s)
Acétylcholine/métabolisme , Phencyclidine/analogues et dérivés , Pipéridines , Acétylcholine/analogues et dérivés , Animaux , Transport biologique/effets des médicaments et des substances chimiques , Phénomènes chimiques , Chimie , Organe électrique/métabolisme , Dose létale 50 , Souris , Structure moléculaire , Stupéfiants , Curarisants dépolarisants , Phencyclidine/synthèse chimique , Phencyclidine/pharmacologie , Phencyclidine/toxicité , Stéréoisomérie , Relation structure-activité , Vésicules synaptiques/métabolisme , Torpedo , Diffraction des rayons X
17.
Mutat Res ; 188(3): 169-74, 1987 Jul.
Article de Anglais | MEDLINE | ID: mdl-3299075

RÉSUMÉ

A considerable number of terpenes that contain an "unsaturated dialdehyde" functionality, and possess various biological activities, such as antimicrobial activity, pungency, antifeedant activity, and/or mutagenicity, have been isolated from natural sources. However, large qualitative and quantitative activity differences have been observed for the natural unsaturated dialdehydes, and small structural changes (e.g., stereoisomerization) seem to dramatically affect the biological activity. As part of a general attempt to study structure-activity relationships for unsaturated dialdehydes, the activity of compounds 1-18 (Table 1) in the Salmonella/microsome assay (strains TA98, TA2637 and TA100) has been investigated. 10 of the compounds were found to possess direct-acting mutagenic activity, although the mutagenic potencies vary considerably in this group (from 430 to 0.32 revertants per nmole in the Salmonella strain TA2637). Some structural features that appear to moderate the activity are discussed. The necessity of an intact unsaturated dialdehyde functionality for the mutagenic activity of isovelleral (1) (see Scheme 1 for names, numbers, and chemical structures) in the Salmonella/microsome assay was demonstrated by chemical conversions: modification of either aldehyde group or reduction of the double bond led to loss of activity.


Sujet(s)
Aldéhydes/toxicité , Mutation/effets des médicaments et des substances chimiques , Biotransformation , Microsomes/métabolisme , Salmonella typhimurium/effets des médicaments et des substances chimiques , Relation structure-activité
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