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2.
Br J Cancer ; 88(6): 803-7, 2003 Mar 24.
Article de Anglais | MEDLINE | ID: mdl-12644813

RÉSUMÉ

In this review, we discuss the available experimental evidences supporting the chemopreventive efficacy of nonsteroidal anti-inflammatory drugs (NSAIDs) on colorectal cancer and the biological basis for their possible role as anticancer agents. Although the comprehension of the mechanisms underlying the effects of these drugs on colon cancer cells is incomplete, research efforts in identifying the biochemical pathway by which NSAIDs exert their chemopreventive effect have provided a rationale for the potential use of NSAIDs alone or in combination with conventional and experimental anticancer agents in the treatment of colorectal cancer. In this paper, we review three main issues: (i) the role of COX-2 in colon cancer; (ii) the common death pathways between NSAIDs and anticancer drugs; and (iii) the biological basis for the combination therapy with COX-2 selective inhibitors and new selective inhibitors of growth factor signal transduction pathways.


Sujet(s)
Anti-inflammatoires non stéroïdiens/pharmacologie , Tumeurs colorectales/traitement médicamenteux , Tumeurs colorectales/prévention et contrôle , Isoenzymes/pharmacologie , Prostaglandin-endoperoxide synthases/pharmacologie , Anti-inflammatoires non stéroïdiens/usage thérapeutique , Apoptose , Chimioprévention , Association thérapeutique , Cyclooxygenase 2 , Substances de croissance/pharmacologie , Humains , Isoenzymes/antagonistes et inhibiteurs , Protéines membranaires , Transduction du signal
3.
Br J Cancer ; 86(9): 1501-9, 2002 May 06.
Article de Anglais | MEDLINE | ID: mdl-11986787

RÉSUMÉ

Numerous studies demonstrate that the chemopreventive effect of non-steroidal anti-inflammatory drugs on colon cancer is mediated through inhibition of cell growth and induction of apoptosis. For these effects non-steroidal anti-inflammatory drugs have been recently employed as sensitising agents in chemotherapy. We have shown previously that treatments with aspirin and NS-398, a cyclo-oxygenase-2 selective inhibitor, affect proliferation, differentiation and apoptosis of the human colon adenocarcinoma Caco-2 cells. In the present study, we have evaluated the effects of aspirin and NS-398 non-steroidal anti-inflammatory drugs on sensitivity of Caco-2 cells to irinotecan (CPT 11) and etoposide (Vp-16) topoisomerase poisons. We find that aspirin co-treatment is able to prevent anticancer drug-induced toxicity, whereas NS-398 co-treatment poorly affects anticancer drug-induced apoptosis. These effects correlate with the different ability of aspirin and NS-398 to interfere with cell cycle during anticancer drug co-treatment. Furthermore, aspirin treatment is associated with an increase in bcl-2 expression, which persists in the presence of the anticancer drugs. Our data indicate that aspirin, but not NS-398, determines a cell cycle arrest associated with death suppression. This provides a plausible mechanism for the inhibition of apoptosis and increase in survival observed in anticancer drug and aspirin co-treatment.


Sujet(s)
Anti-inflammatoires non stéroïdiens/pharmacologie , Apoptose/effets des médicaments et des substances chimiques , Acide acétylsalicylique/pharmacologie , Antienzymes/pharmacologie , Nitrobenzènes/pharmacologie , Sulfonamides/pharmacologie , Inhibiteurs des topoisomérases , Cellules Caco-2 , Camptothécine/analogues et dérivés , Camptothécine/pharmacologie , Survie cellulaire , Étoposide/pharmacologie , Humains , Irinotécan
4.
Oncogene ; 19(48): 5517-24, 2000 Nov 16.
Article de Anglais | MEDLINE | ID: mdl-11114729

RÉSUMÉ

Nonsteroidal anti-inflammatory drugs reduce the risk of colon cancer and this effect is mediated in part through inhibition of type 2 prostaglandin endoperoxide synthase/ cyclo-oxygenase (COX-2). In the present study, we demonstrate that COX-2 expression and PGE2 synthesis are up-regulated by an IGF-II/IGF-I receptor autocrine pathway in Caco-2 colon carcinoma cells. COX-2 mRNA and PGE2 levels are higher in proliferating cells compared with post-confluent differentiated cells and in cells that constitutively overexpress IGF-II. Up-regulation of COX-2 expression by IGF-II is mediated through activation of IGF-I receptor because: (i) treatment of Caco-2 cells with a blocking antibody to the IGF-I receptor inhibits COX-2 mRNA expression; (ii) transfection of Caco-2 cells with a dominant negative IGF-I receptor reduces COX-2 expression and activity. Also, the blockade of the PI3-kinase, that mediates the proliferative effect of IGF-I receptor in Caco-2 cells, inhibits IGF-II-dependent COX-2 up-regulation and PGE2 synthesis. Moreover, COX-2 expression and activity inversely correlate with the increase of apoptosis in parental, IGF-II and dominant-negative IGF-I receptor transfected cells. This study suggests that induction of proliferation and tumor progression of colon cancer cells by the IGF-II/IGF-I receptor pathway may depend on the activation of COX-2-related events.


Sujet(s)
Cellules Caco-2/métabolisme , Dinoprostone/biosynthèse , Facteur de croissance IGF-II/physiologie , Isoenzymes/biosynthèse , Prostaglandin-endoperoxide synthases/biosynthèse , ARN messager/biosynthèse , Récepteur IGF de type 1/physiologie , Anti-inflammatoires non stéroïdiens/pharmacologie , Anticorps monoclonaux/pharmacologie , Apoptose/effets des médicaments et des substances chimiques , Apoptose/physiologie , Cellules Caco-2/enzymologie , Division cellulaire/physiologie , Cyclooxygenase 2 , Inhibiteurs de la cyclooxygénase 2 , Inhibiteurs des cyclooxygénases/pharmacologie , Évolution de la maladie , Humains , Facteur de croissance IGF-II/antagonistes et inhibiteurs , Facteur de croissance IGF-II/biosynthèse , Isoenzymes/génétique , Isoenzymes/métabolisme , Système de signalisation des MAP kinases/physiologie , Protéines membranaires , Mitogen-Activated Protein Kinase Kinases/antagonistes et inhibiteurs , Nitrobenzènes/pharmacologie , Inhibiteurs des phosphoinositide-3 kinases , Prostaglandin-endoperoxide synthases/génétique , Prostaglandin-endoperoxide synthases/métabolisme , ARN messager/génétique , Récepteur IGF de type 1/antagonistes et inhibiteurs , Récepteur IGF de type 1/génétique , Transduction du signal/physiologie , Sulfonamides/pharmacologie , Transfection , Régulation positive/physiologie
5.
J Clin Gastroenterol ; 31(2): 164-8, 2000 Sep.
Article de Anglais | MEDLINE | ID: mdl-10993437

RÉSUMÉ

The aim of the current study was to compare Levovist-enhanced power Doppler (PD) imaging with contrast-enhanced spiral computed tomography (CT) in the evaluation of intratumoral vascularity of hepatocellular carcinomas at diagnosis and after percutaneous ethanol injection (PEI). Nineteen patients with hepatocellular carcinoma (HCC) underwent PD with and without Levovist and spiral CT at diagnosis and 1 month after PEI treatment. Compared to spiral CT at baseline evaluation, the PD showed intratumoral vascularity in 36.8% of the cases; this percentage reached 78.9% after Levovist enhancement. One month after PEI, only 5 out of 19 treated HCCs appeared as hypodense areas at CT and showed no contrast enhancement. Only 3 of the 14 patients with a positive spiral CT scan were positive at the PD performed without the Levovist administration (sensitivity, 21.4%). The use of contrast-enhanced ultrasonography led to detection of residual signal in six other HCCs treated by ethanol injection (sensitivity, 64.2%). We confirm that spiral CT is the most sensitive and accurate technique in evaluating the effect of ethanol injection in HCC. It correctly identifies most cases of treatment failure as enhanced areas within the lesion. The lower rate of detection of tumoral vascularity by Doppler sonography was significantly increased by Levovist. The evidence of residual vascularity within HCC at Levovist Doppler sonography allows the targeting of additional ethanol injections.


Sujet(s)
Carcinome hépatocellulaire/diagnostic , Carcinome hépatocellulaire/traitement médicamenteux , Produits de contraste , Éthanol/administration et posologie , Tumeurs du foie/diagnostic , Tumeurs du foie/traitement médicamenteux , Polyosides , Tomodensitométrie/méthodes , Échographie-doppler/méthodes , Sujet âgé , Carcinome hépatocellulaire/vascularisation , Femelle , Humains , Amélioration d'image , Injections sous-cutanées , Tumeurs du foie/vascularisation , Mâle , Adulte d'âge moyen , Sensibilité et spécificité
6.
Ann Oncol ; 11(5): 613-6, 2000 May.
Article de Anglais | MEDLINE | ID: mdl-10907958

RÉSUMÉ

BACKGROUND: Gemcitabine is active in patients with otherwise resistant or refractory ovarian cancer. As the drug is well tolerated, studies using gemcitabine combined with other antineoplastic agents are needed. The aim of the study was to determine the maximum tolerated dose (MTD) of epirubicin combined with gemcitabine, with and without support of G-CSF. PATIENTS AND METHODS: Patients with platinum-resistant or refractory ovarian cancer were eligible. Gemcitabine (G) (starting dose 800 mg/m2 day 1 and 8; 200 mg/m2 escalation per level) and epirubicin (E) (starting dose 60 mg/m2 day 1; 15 mg/m2 escalation per level) were given every 21 days for four to six cycles. G-CSF (filgrastim 5 microg/kg/die) was given in case of grade 4 neutropenia (levels without support) or from day 9 up to leukocyte count > 10.000/mm3 after nadir (levels with support). Cohorts of three patients were enrolled at each level, and another three patients were planned, if one dose-limiting toxicity (DLT) was registered. MTD was determined first without and then with G-CSF. RESULTS: Four levels were studied (G 800 + E 60; G 1000 + E 60; G 1000 + E 75; G 1000 + E 75 + G-CSF) with four, four, three and three patients enrolled, respectively. DLT (grade 4 febrile neutropenia) was observed in two patients at level 3. Thus, G1000 + E 60 mg/m2 was the MTD without G-CSF. The addition of prophylactic G-CSF did not allow a further increase of the dose and grade 4 thrombocytopenia was the DLT at level 4. Non-hematological toxicity was mild. Grade 2 mucositis was reported in four patients. Among the 13 patients with measurable or evaluable disease, 3 partial responses were observed for an overall response rate of 23.1%. CONCLUSIONS: The combination of gemcitabine 1000 mg/m2 (day 1, 8) and epirubicin at 60 mg/m2 (day 1) is a feasible therapy. Grade 4 neutropenia is frequent and G-CSF support is often required. With prophylactic support of G-CSF, the DLT is thrombocytopenia.


Sujet(s)
Protocoles de polychimiothérapie antinéoplasique/usage thérapeutique , Carcinomes/traitement médicamenteux , Tumeurs de l'ovaire/traitement médicamenteux , Adulte , Sujet âgé , Protocoles de polychimiothérapie antinéoplasique/effets indésirables , Carcinomes/anatomopathologie , Désoxycytidine/administration et posologie , Désoxycytidine/analogues et dérivés , Relation dose-effet des médicaments , Résistance aux médicaments antinéoplasiques , Épirubicine/administration et posologie , Femelle , Facteur de stimulation des colonies de granulocytes/administration et posologie , Humains , Adulte d'âge moyen , Neutropénie/induit chimiquement , Tumeurs de l'ovaire/anatomopathologie , Résultat thérapeutique ,
7.
Ann Oncol ; 11(4): 455-9, 2000 Apr.
Article de Anglais | MEDLINE | ID: mdl-10847466

RÉSUMÉ

BACKGROUND: Cisplatin and paclitaxel are active in cervical cancer and both are able to potentiate the effects of radiotherapy. In this study we evaluated the maximum-tolerated dose (MTD) of paclitaxel in combination with a fixed dose of cisplatin when given weekly concurrently with pelvic radiotherapy to patients with carcinoma of the cervix uteri. PATIENTS AND METHODS: Eighteen patients with cervical cancer were enrolled in this study. Cisplatin (30 mg/m2) and paclitaxel (starting dose 40 mg/m2; 5 mg/m2 escalation per level) were given on day 1 of radiotherapy and then weekly for six times. Radiotherapy was given to the pelvis with a four-field box technique for five days each week. Patients received 65 Gy in 1.8 Gy fractions. Cohorts of three patients were enrolled at each level and three further patients were included if one or two dose-limiting severe adverse events (SAE) were recorded. SAE was defined as grade 3 or 4 nonhematologic toxicity, excluding nausea or vomiting and alopecia, grade 4 neutropenia or thrombocytopenia, and prolonged (> 1 week) neutropenia or thrombocytopenia. RESULTS: Four levels were studied (paclitaxel 40, 45, 50, 55 mg/m2) with three, five, four and six patients enrolled, respectively. The MTD of paclitaxel was found at 50 mg/m2/wk and cisplatin 30 mg/m2/wk. Diarrhea was the dose-limiting toxicity. Thirteen patients were evaluable for response: seven complete and five partial responses were obtained with an overall response rate of 92.3%. CONCLUSIONS: The MTD of paclitaxel is 50 mg/m2/wk when associated to cisplatin 30 mg/m2/wk and concurrent pelvic radiotherapy. Diarrhea is the dose limiting side effect. Preliminary data suggest that concurrent chemoradiotherapy with paclitaxel and cisplatin could be a very active treatment for patients with locally advanced carcinoma of the cervix.


Sujet(s)
Adénocarcinome/traitement médicamenteux , Adénocarcinome/radiothérapie , Protocoles de polychimiothérapie antinéoplasique/usage thérapeutique , Carcinome épidermoïde/traitement médicamenteux , Carcinome épidermoïde/radiothérapie , Tumeurs du col de l'utérus/traitement médicamenteux , Tumeurs du col de l'utérus/radiothérapie , Adénocarcinome/anatomopathologie , Adulte , Sujet âgé , Protocoles de polychimiothérapie antinéoplasique/effets indésirables , Carcinome épidermoïde/anatomopathologie , Cisplatine/administration et posologie , Association thérapeutique , Diarrhée/induit chimiquement , Relation dose-effet des médicaments , Calendrier d'administration des médicaments , Femelle , Humains , Adulte d'âge moyen , Paclitaxel/administration et posologie , Taxoïdes , Tumeurs du col de l'utérus/anatomopathologie
8.
Anticancer Res ; 20(5C): 4023-9, 2000.
Article de Anglais | MEDLINE | ID: mdl-11268496

RÉSUMÉ

BACKGROUND: Prognosis of advanced ovarian cancer is unsatisfactory. Chemotherapy can be intensified combining active drugs at their highest possible doses. PATIENTS AND METHODS: In this phase I/II trial, 77 untreated patients received escalating doses of paclitaxel (135, 155, 175, 195 and 215 mg/m2, infused over 3 hours) with carboplatin (AUC 3.6) and cisplatin (60 mg/m2). Nine, 16, 13, 8 and 3 patients were treated at the five levels, respectively. A further 28 patients were treated at the maximum tolerable dose (MTD). RESULTS: Dose-limiting toxicities (one WHO grade 3 constipation, one grade 2 prolonged peripheral neurotoxicity and one grade 3 cardiac toxicity) occurred at 215 mg/m2 in 3 out of 3 patients. MTD was reached at level 4 paclitaxel dose (195 mg/m2). Response was evaluated in 62 patients. A complete response was achieved in 23 patients (37.1%-95% CI 25.2-50.3), including 16 (25.8%) pathological and partial response in 28 (45.2%), for an overall response rate of 82.3% (95% exact CL: 70.5%-90.8%). The probability of response was affected by the degree of initial debulking (p = 0.002) and not by the paclitaxel dose. In patients with stage III-IV disease, median progression-free survival was 17 months (95% CI 14-25). After a median follow-up of 28 months, median survival had not been reached; 2-year estimated survival was 67%. CONCLUSION: Paclitaxel can be safely given at the dose of 195 mg/m2 in combination with carboplatin (AUC 3.6) and cisplatin (60 mg/m2). This combination is active and safe and could be considered in clinical settings requiring intensive short treatment.


Sujet(s)
Protocoles de polychimiothérapie antinéoplasique/usage thérapeutique , Carcinome épidermoïde/traitement médicamenteux , Tumeurs de l'ovaire/traitement médicamenteux , Adulte , Sujet âgé , Protocoles de polychimiothérapie antinéoplasique/effets indésirables , Carboplatine/administration et posologie , Carcinome épidermoïde/mortalité , Carcinome épidermoïde/anatomopathologie , Carcinome épidermoïde/chirurgie , Cisplatine/administration et posologie , Survie sans rechute , Relation dose-effet des médicaments , Femelle , Études de suivi , Humains , Adulte d'âge moyen , Stadification tumorale , Tumeurs de l'ovaire/mortalité , Tumeurs de l'ovaire/anatomopathologie , Tumeurs de l'ovaire/chirurgie , Paclitaxel/administration et posologie , Taux de survie , Facteurs temps
9.
Oncology ; 56(4): 267-73, 1999.
Article de Anglais | MEDLINE | ID: mdl-10343189

RÉSUMÉ

The aim of the study was to determine the maximum tolerated dose (MTD) of epirubicin combined with a fixed dose of paclitaxel, without and with support of filgrastim, in patients with platinum resistant or refractory ovarian cancer. Paclitaxel (150 mg/m2) and epirubicin (starting dose 90 mg/m2, 15 mg/m2 escalation per level) were given on day 1, every 28 days for 4-6 cycles. Filgrastim (F) (5 microg/kg/die) was given in case of grade 4 leukopenia (levels without support) or from day 4 up to leukocyte count >10,000/mm3 after nadir (levels with support). Cohorts of 3 patients were enrolled at each level and further 3 patients were planned if 1 or 2 unacceptable toxic events (UTE) were registered. MTD was determined first without and then with filgrastim. Four levels were studied (90, 90+F, 105+F, 120+F) with 4, 6, 5 and 4 patients enrolled, respectively. UTE (grade 4 neutropenia) were observed in 3 patients at level 1. Thus, 90 mg/m2 was the MTD for epirubicin without filgrastim. MTD of epirubicin with filgrastim was not reached at 120 mg/m2. Hematological toxicity was mild. Grade 3 mucositis was reported in 1 patient. Among the 14 patients with measurable or evaluable disease, 3 objective responses were observed (1 complete and 2 partial) for an overall response rate of 21.4%. The combination of paclitaxel 150 mg/m2 and epirubicin at 120 mg/m2 with filgrastim is a feasible therapy. Grade 4 leukopenia is the dose limiting toxicity using epirubicin at 90 mg/m2 without filgrastim.


Sujet(s)
Protocoles de polychimiothérapie antinéoplasique/usage thérapeutique , Facteur de stimulation des colonies de granulocytes/usage thérapeutique , Hémopathies/prévention et contrôle , Tumeurs de l'ovaire/traitement médicamenteux , Adulte , Sujet âgé , Antibiotiques antinéoplasiques/administration et posologie , Antinéoplasiques d'origine végétale/administration et posologie , Protocoles de polychimiothérapie antinéoplasique/effets indésirables , Calendrier d'administration des médicaments , Résistance aux médicaments antinéoplasiques , Épirubicine/administration et posologie , Femelle , Filgrastim , Hémopathies/induit chimiquement , Humains , Numération des leucocytes/effets des médicaments et des substances chimiques , Adulte d'âge moyen , Tumeurs de l'ovaire/anatomopathologie , Paclitaxel/administration et posologie , Composés du platine/usage thérapeutique , Protéines recombinantes , Résultat thérapeutique
10.
Gastroenterology ; 116(6): 1358-66, 1999 Jun.
Article de Anglais | MEDLINE | ID: mdl-10348819

RÉSUMÉ

BACKGROUND & AIMS: We have previously shown that autocrine insulin-like growth factor (IGF)-II synthesis through IGF-I receptor stimulates proliferation and inhibits differentiation of Caco-2 cells. To demonstrate whether differentiation of Caco-2 cells is dependent on cell growth status, we analyzed the effect of cell cycle arrest on differentiation of wild-type and IGF-II-overexpressing cells. METHODS: Cells were treated with drugs that inhibit the progression either to S phase (l-b-D-arabinofuranosylcytosine or M phase (nocodazole). Cell differentiation was analyzed by assessing apolipoprotein A-1 and sucrase-isomaltase expression. Cell proliferation and DNA content were assessed by thymidine incorporation and fluorescence-activated cell sorter analysis, respectively. Cell cycle regulatory molecules were analyzed by assessing p21 and retinoplasma protein (pRb) expression and pRb phosphorylation. RESULTS: Cell cycle block at G1-S phase was associated with increased expression of differentiation markers in both parental and IGF-II-transfected cells. On the contrary, cell cycle arrest at G2-M phase correlated with the expression of differentiation markers in parental but not in IGF-II-transfected cells. Constitutive IGF-II-expressing cells actively incorporated thymidine and showed an increase in the proportion of cells with >4N DNA ploidy in the presence of nocodazole. Nocodazole treatment of constitutive IGF-II-expressing cells stimulated p21 expression in the presence of hyperphosphorylated pRb. CONCLUSIONS: The data show that cell cycle arrest increases differentiation of Caco-2 cells. IGF-II-mediated proliferation may prevent cell differentiation through effects on control cell checkpoint proteins.


Sujet(s)
Phase G1/physiologie , Phase G2/physiologie , Facteur de croissance IGF-II/métabolisme , Muqueuse intestinale/cytologie , Muqueuse intestinale/métabolisme , Antibactériens/pharmacologie , Cellules Caco-2 , Cycle cellulaire/effets des médicaments et des substances chimiques , Cycle cellulaire/physiologie , Différenciation cellulaire/effets des médicaments et des substances chimiques , Différenciation cellulaire/physiologie , Division cellulaire/physiologie , Inhibiteur p21 de kinase cycline-dépendante , Cyclines/métabolisme , Cytarabine/pharmacologie , Résistance microbienne aux médicaments/génétique , Humains , Facteur de croissance IGF-II/génétique , Néomycine/pharmacologie , Nocodazole/pharmacologie , Ploïdies , Protéine du rétinoblastome/métabolisme , Transfection
11.
J Clin Oncol ; 17(3): 756-60, 1999 Mar.
Article de Anglais | MEDLINE | ID: mdl-10071263

RÉSUMÉ

PURPOSE: To evaluate the activity and toxicity of the combination of cisplatin (80 mg/m2 day 1) and vinorelbine (25 mg/m2 days 1 and 8) in patients with carcinoma of the uterine cervix that has not been previously treated with chemotherapy. PATIENTS AND METHODS: Fifty patients with cervical cancer were enrolled onto this study (27 stage IB-III, 23 stage IVB-recurrent). A two-stage optimal Simon design was applied. Thirteen responders of 29 treated patients were required to proceed beyond the first stage, and 28 responders were needed overall. RESULTS: Hematologic toxicity was mild, with neutropenia being the most frequent side effect. Nonhematologic toxicity was frequent but never severe; one patient had grade 3 peripheral neurotoxicity. Objective responses were recorded for 32 patients (64%): 11 patients (22%) achieved a complete response (CR) and 21 patients (42%) achieved a partial response (PR). The response rate was 81.5% in patients with IB-III stage (25.9% CR rate) and 43.5% in patients with IVB-recurrent disease (17.4% CR rate). Responses were seen both in stage IVB patients (one CR and two PRs, for an overall rate of 37.5%) and in patients with recurrent disease (three CRs + four PRs, for an overall rate of 46.7%). CONCLUSION: The combination of cisplatin and vinorelbine is an active regimen in the treatment of patients with early-stage and advanced carcinoma of the uterine cervix. The hematologic and nonhematologic toxicity of this combination is mild.


Sujet(s)
Protocoles de polychimiothérapie antinéoplasique/usage thérapeutique , Tumeurs du col de l'utérus/traitement médicamenteux , Adulte , Sujet âgé , Protocoles de polychimiothérapie antinéoplasique/effets indésirables , Cisplatine/administration et posologie , Femelle , Hémopathies/induit chimiquement , Humains , Adulte d'âge moyen , Stadification tumorale , Neuropathies périphériques/induit chimiquement , Induction de rémission , Tumeurs du col de l'utérus/anatomopathologie , Vinblastine/administration et posologie , Vinblastine/analogues et dérivés , Vinorelbine
13.
Int J Cancer ; 73(6): 880-4, 1997 Dec 10.
Article de Anglais | MEDLINE | ID: mdl-9399670

RÉSUMÉ

Several lines of evidence suggest that long-term treatment with non-steroidal anti-inflammatory drugs may reduce the risk of colon cancer and the size and number of colonic polyps in patients with familial adenomatous polyposis. Aspirin has also been shown to inhibit cell proliferation in human tumor cell lines and to induce apoptosis in colonic mucosa of familial polyposis patients. To elucidate the molecular mechanisms of the antiproliferative action of aspirin, we studied the effects of aspirin on cell growth and differentiation of the human colon carcinoma Caco-2 cell line. These cells represent a useful tool for studying the mechanisms involved in the regulation of cell growth and differentiation of intestinal epithelial cells since they spontaneously differentiate into polarized cells, expressing brush border enzymes. We show in this study that aspirin (0.1-10 mM) induces a profound inhibition of cell replication as assessed either by cell counts or thymidine incorporation. Moreover, aspirin concentrations of 5 and 10 mM induce apoptosis, whereas concentrations of 1 and 2 mM do not. The inhibition of growth is associated with a dose-dependent reduction in insulin-like growth factor II mRNA expression and with an increase in sucrase activity (a brush border enzyme) and apolipoprotein A-I mRNA expression, 2 specific markers of the differentiative status of this cell line. Our data thus show that aspirin-dependent inhibition of cell growth is associated with the enterocyte-like differentiation of Caco-2 cells.


Sujet(s)
Adénocarcinome/anatomopathologie , Anti-inflammatoires non stéroïdiens/pharmacologie , Acide acétylsalicylique/pharmacologie , Tumeurs du côlon/anatomopathologie , Adénocarcinome/métabolisme , Apolipoprotéine A-I/biosynthèse , Apoptose , Technique de Northern , Cellules Caco-2 , Différenciation cellulaire/effets des médicaments et des substances chimiques , Division cellulaire/effets des médicaments et des substances chimiques , Tumeurs du côlon/métabolisme , ADN/analyse , Relation dose-effet des médicaments , Humains , Facteur de croissance IGF-II/biosynthèse , ARN messager/analyse , Phase S/effets des médicaments et des substances chimiques , Invertase/métabolisme , Thymidine/métabolisme
15.
Eur J Gastroenterol Hepatol ; 9(3): 283-6, 1997 Mar.
Article de Anglais | MEDLINE | ID: mdl-9096431

RÉSUMÉ

BACKGROUND: Patients with alcoholic cirrhosis show hypogonadism and feminization associated with sex hormone imbalance due to enhanced aromatization of testosterone and subsequent reduced testosterone and increased oestradiol blood levels. Because oestrogens modulate hepatocyte proliferation and oestrogen receptors are present in liver cirrhosis and hepatocellular carcinoma, it has been proposed that sex hormone imbalance can play a role in liver carcinogenesis. Trials with the oestrogen receptor antagonist tamoxifen have been performed with conflicting results. OBJECTIVES: To investigate oestradiol and testosterone blood levels in men with viral cirrhosis and hepatocellular carcinoma and also to investigate changes in sex hormone circulating levels induced by tamoxifen treatment. PATIENTS AND METHODS: Oestradiol and testosterone blood levels were evaluated in 32 male patients with postviral cirrhosis and hepatocellular carcinoma at the time of diagnosis and during the follow-up, and in 20 healthy controls. In eight patients, hormone levels were also assayed during treatment with tamoxifen (40 mg/day). No patient had a history of high alcohol intake. RESULTS: Oestradiol values observed at the time of diagnosis were 56.1 +/- 54.5 pmol/l, while testosterone values were 13.6 +/- 8.0 pmol/l. There was no relationship between oestrogen values and age, while higher oestradiol values were observed in patients with advanced cirrhosis (Child B and C); conversely, testosterone levels progressively and significantly decreased from cirrhosis Child A (15.1 +/- 9.7) to C (7.7 +/- 7.1) (P < 0.05). Tamoxifen treatment (40mg/day) for 1 month in eight patients increased oestradiol values (62.2 +/- 77.0 vs. 156.4 +/- 83 pmol/l, P < 0.05), while testosterone levels decreased (15.1 +/- 6.8 vs. 8.5 +/- 10.6 pmol/l). However, these changes were not associated with clinical signs or symptoms of feminization. Oestrogen levels decreased after 6 months of tamoxifen treatment. No significant change in hormone levels was observed in patients not treated with tamoxifen. Unlike patients with alcoholic cirrhosis, in male patients with viral cirrhosis and hepatocellular carcinoma there were no significant alterations in blood oestradiol and testosterone levels, although a certain degree of sex hormone imbalance was observed in those with advanced cirrhosis. Treatment with tamoxifen (40 mg/day) did not induce clinical manifestations of sex hormone imbalance.


Sujet(s)
Carcinome hépatocellulaire/sang , Oestradiol/sang , Cirrhose du foie/sang , Tumeurs du foie/sang , Tamoxifène/pharmacologie , Testostérone/sang , Facteurs âges , Sujet âgé , Carcinome hépatocellulaire/complications , Humains , Cirrhose du foie/complications , Tumeurs du foie/complications , Mâle , Adulte d'âge moyen , Études prospectives
16.
Ital J Gastroenterol Hepatol ; 29(6): 548-53, 1997 Dec.
Article de Anglais | MEDLINE | ID: mdl-9513831

RÉSUMÉ

BACKGROUND AND AIMS: The aim of the present study was to compare power Doppler imaging with traditional color Doppler imaging and with contrast enhanced computer tomography in the evaluation of intratumoral vascularity of hepatocellular carcinomas at diagnosis and in response to percutaneous ethanol injection. PATIENTS AND METHODS: Sixteen patients with hepatocellular carcinoma underwent colour Doppler, power Doppler and computed tomography at diagnosis. Seventeen patients were studied by the three techniques one month after percutaneous ethanol injection treatment. RESULTS: At baseline evaluation, power Doppler and color Doppler were always in agreement and, with the exception of one case, were also in agreement with the computerized tomography scan. On the contrary, power Doppler and computerized tomography are more sensitive than color Doppler in the evaluation of residual vascularized tumoral tissue after percutaneous ethanol injection. In 3 patients, residual vascularity was demonstrated only by computerized tomography while color and power Doppler were negative. In another 3 cases, a positive power Doppler signal, with a typical arterial Doppler spectrum, was observed while color Doppler and computerized tomography were negative. In these patients, cancer relapse was clinically evident after a few months and treatment was repeated to obtain complete necrosis. CONCLUSIONS: We conclude that only the integration of the results of all these techniques can reliably evaluate tumoral vascularity after percutaneous ethanol injection.


Sujet(s)
Carcinome hépatocellulaire/imagerie diagnostique , Carcinome hépatocellulaire/traitement médicamenteux , Éthanol/administration et posologie , Tumeurs du foie/imagerie diagnostique , Tumeurs du foie/traitement médicamenteux , Tomodensitométrie/méthodes , Échographie-doppler , Adulte , Sujet âgé , Carcinome hépatocellulaire/diagnostic , Produits de contraste , Femelle , Études de suivi , Humains , Injections sous-cutanées , Foie/vascularisation , Foie/imagerie diagnostique , Tumeurs du foie/diagnostic , Mâle , Microcirculation/imagerie diagnostique , Adulte d'âge moyen , Pronostic , Amélioration d'image radiographique , Sensibilité et spécificité , Échographie-doppler couleur
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