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Julien Taïeb

Publications and source records attributed to Julien Taïeb.

17 recordsLinked to original sources
PubMed2006

Irinotecan as first-line chemotherapy in patients with advanced hepatocellular carcinoma: a multicenter phase II study with dose adjustment according to baseline serum bilirubin level.

This study assessed the clinical activity and safety of irinotecan (CPT-11) in patients with advanced hepatocellular carcinoma (HCC) using dose adjustment according to baseline serum bilirubin level. Patients with advanced HCC received CPT-11 at a dose of 350 mg/m(2) when total bilirubin level was 1.5 times upper limit of normal (ULN) (group A), or 200 mg/m(2) when total bilirubin level was between 1.51 and 3 ULN (group B). No objective response, one minor response and 12 disease stabilizations were observed in the 29 patients (group A, 23; group B, 6) enrolled. Median time to progression and overall survival were 3.1 months (95% confidence interval [CI]: 2.0-4.0) and 7.4 months (95% CI: 3.9-12.0), respectively. Grade 3-4 adverse events (mostly neutropenia [47%], anaemia [24%], and diarrhoea [17%]) were more frequent in group A (74%) than in group B (33%) (P = 0.086). This study found favourable toxicity profile using dosage adjustment to the baseline total bilirubin level in patients with bilirubin level comprised between 1.51 and 3 ULN. However, the antitumour activity of single agent CPT-11 was not significant in advanced HCC.

Adolescent↗
PubMed2005

Intensive systemic chemotherapy combined with surgery for metastatic colorectal cancer: results of a phase II study.

PURPOSE: To evaluate the efficacy and tolerability of the metastatic irinotecan plus oxaliplatin (MIROX) strategy (adjuvant FOLFOX-7 followed by FOLFIRI), in patients with resectable metastatic colorectal cancer. PATIENTS AND METHODS: Forty-seven patients with resectable metastases of colorectal cancer were prospectively enrolled onto this study. Treatment consisted of six cycles of leucovorin 400 mg/m(2), oxaliplatin 130 mg/m(2) in a 120-minute infusion, and fluorouracil (FU) 2,400 mg/m(2) in a 46-hour infusion, every 2 weeks (FOLFOX-7), followed by six cycles of leucovorin 400 mg/m(2), irinotecan 180 mg/m(2) in a 90-minute infusion, bolus FU 400 mg/m(2), and FU 2,400 mg/m(2) as a 46-hour infusion, every 2 weeks (FOLFIRI). Surgery was performed before chemotherapy in 25 patients and after six cycles of FOLFOX-7 in 22 patients (six cycles of FOLFIRI were administered after surgery). RESULTS: All but one of the patients underwent curative surgery. Two patients refused postoperative chemotherapy. Tolerability was generally good. The main toxicities were grade 3 to 4 neutropenia (13%) and thrombocytopenia (11%); no febrile neutropenia or bleeding occurred, and there were no deaths caused by toxicity. Two pathologically confirmed complete responses and 15 partial responses were obtained with FOLFOX-7 in the 22 patients who received this regimen before surgery (overall response rate, 77%; 95% CI, 68 to 86). The median disease-free survival time was 21 months; the median overall survival has not yet been reached. The 2-year overall and disease-free survival rates were 89% and 47%, respectively. CONCLUSION: The MIROX strategy is feasible and well tolerated by patients with resectable metastatic colorectal cancer. Progression-free and overall survival rates are promising, with a median of 38 months of follow-up. This strategy currently is being compared with the leucovorin and FU regimen in a phase III trial.

Adult↗
PubMed2005

The potential of exosomes in immunotherapy.

In 1996, B cell-derived exosome immunogenicity was first reported. In 1998, dendritic cell-derived exosomes were also shown to have immunogenic properties in mice, leading to tumour eradication. These observations showed for the first time that exosomes were bioactive vesicles with immuno-regulatory roles and potent antitumour effects. Exosomes are secreted vesicles formed in late endocytic compartments (multivesicular bodies). Vesicles exocytosed from multivesicular bodies into the extracellular medium are referred to as 'exosomes' and should not be confused with the more recently described 'ribonuclease complex' also named exosome. Exosomes are vesicles of 50-100 nm in diameter, formed by inward budding of the endosomal membrane in a process that sequesters particular proteins and lipids. This review will describe the biogenesis, the protein and lipid compositions, and the biological functions of exosomes; this review will also present their immunostimulatory functions in mice and humans, and will discuss their possible use as cancer vaccines.

Animals↗
PubMed2005

Dendritic cell-derived exosomes as cell-free peptide-based vaccines.

Dendritic cells (DC) are professional antigen-presenting cells and the only ones capable of inducing primary cytotoxic immune responses both in vivo and in vitro. DCs secrete a 60-100 nm membrane vesicle population of endocytic origin, called exosomes. The lipid and protein composition of DC-derived exosomes (DEX) is now well characterized. Besides MHC and costimulatory molecules, DEX bear several adhesion proteins, which are probably involved in their specific targeting. DEX also accumulate several cytosolic factors, most likely involved in exosome's biogenesis in late endosomes. In 1998, we reported that DEX are immunogenic in mice and lead to tumor rejection. These findings have renewed the interest in DEX. The current challenge consists of understanding the mechanisms and the physiological relevance of DEX, which could contribute to the design of the optimal DEX-based vaccination. In this review, we focus on the biological features of DEX and their immunostimulatory functions in mice and humans, and we discuss their potential clinical implementation in the immunotherapy of cancer.

Clinical Trials as Topic↗
PubMed2004

Exosomes as potent cell-free peptide-based vaccine. II. Exosomes in CpG adjuvants efficiently prime naive Tc1 lymphocytes leading to tumor rejection.

Ideal vaccines should be stable, safe, molecularly defined, and out-of-shelf reagents efficient at triggering effector and memory Ag-specific T cell-based immune responses. Dendritic cell-derived exosomes could be considered as novel peptide-based vaccines because exosomes harbor a discrete set of proteins, bear functional MHC class I and II molecules that can be loaded with synthetic peptides of choice, and are stable reagents that were safely used in pioneering phase I studies. However, we showed in part I that exosomes are efficient to promote primary MHC class I-restricted effector CD8(+) T cell responses only when transferred onto mature DC in vivo. In this work, we bring evidence that among the clinically available reagents, Toll-like receptor 3 and 9 ligands are elective adjuvants capable of triggering efficient MHC-restricted CD8(+) T cell responses when combined to exosomes. Exosome immunogenicity across species allowed to verify the efficacy of good manufactory procedures-manufactured human exosomes admixed with CpG oligonucleotides in prophylactic and therapeutic settings of melanoma in HLA-A2 transgenic mice. CpG adjuvants appear to be ideal adjuvants for exosome-based cancer vaccines.

Adjuvants, Immunologic↗
PubMed2004

Exosome-based immunotherapy.

Exosomes are small membrane vesicles originating from late endosomes and secreted by hematopoietic and epithelial cells in culture. Exosome proteic and lipid composition is unique and might shed some light into exosome biogenesis and function. Exosomes secreted from professional antigen-presenting cells (i.e., B lymphocytes and dendritic cells) are enriched in MHC class I and II complexes, costimulatory molecules, and hsp70-90 chaperones, and have therefore been more extensively studied for their immunomodulatory capacities in vitro and in vivo. This review will present the main biological features pertaining to tumor or DC-derived exosomes, will emphasize their immunostimulatory function, and will discuss their implementation in cancer immunotherapy.

Antigen Presentation↗
PubMed2004

Novel mode of action of c-kit tyrosine kinase inhibitors leading to NK cell-dependent antitumor effects.

Mutant isoforms of the KIT or PDGF receptors expressed by gastrointestinal stromal tumors (GISTs) are considered the therapeutic targets for STI571 (imatinib mesylate; Gleevec), a specific inhibitor of these tyrosine kinase receptors. Case reports of clinical efficacy of Gleevec in GISTs lacking the typical receptor mutations prompted a search for an alternate mode of action. Here we show that Gleevec can act on host DCs to promote NK cell activation. DC-mediated NK cell activation was triggered in vitro and in vivo by treatment of DCs with Gleevec as well as by a loss-of-function mutation of KIT. Therefore, tumors that are refractory to the antiproliferative effects of Gleevec in vitro responded to Gleevec in vivo in an NK cell-dependent manner. Longitudinal studies of Gleevec-treated GIST patients revealed a therapy-induced increase in IFN-gamma production by NK cells, correlating with an enhanced antitumor response. These data point to a novel mode of antitumor action for Gleevec.

Animals↗
PubMed2003

Gemcitabine plus oxaliplatin for patients with advanced hepatocellular carcinoma using two different schedules.

BACKGROUND: New therapies are needed to improve the prognosis of patients with advanced hepatocellular carcinoma (HCC). Various gemcitabine-oxaliplatin combinations have been tested recently in patients with ovarian and pancreatic carcinoma, yielding interesting results with little toxicity. Therefore, the authors evaluated the activity and toxicity of two such combinations in patients with HCC. METHODS: Twenty-one patients were enrolled prospectively in the study. Eleven patients received gemcitabine 1000 mg/m2 on Day 1 and oxaliplatin 100 mg/m2 on Day 2 (GEMOX-1), and 10 patients received gemcitabine 1500 mg/m2 on Day 1 followed by oxaliplatin 85 mg/m2 on Day 1 (GEMOX-2). Treatment was repeated every 2 weeks until disease progression developed or until unacceptable adverse effects occurred. RESULTS: All patients were assessable for response and toxicity. Four patients (19%) achieved objective responses (95% confidence interval, 13-26%), including 3 patients in the GEMOX-1 group and 1 patient in the GEMOX-2 group. Ten patients (48%) had stable disease, and 7 patients (33%) experienced disease progression. The median progression-free survival was 5 months, and the median overall survival was 12 months. Fifty-four percent of patients in the GEMOX-1 group and 50% of patients in the GEMOX-2 group had received previous systemic chemotherapy or cisplatin-based chemoembolization. Grade 3-4 hematologic toxicity, according to National Cancer Institute Common Toxicity Criteria, consisted of thrombocytopenia (GEMOX-1 vs. GEMOX-2, 18% vs. 40%) and neutropenia (0% vs. 30%). No Grade 3-4 nonhematologic toxicity was observed, except for 1 episode of Grade 3 diarrhea. Grade 1 neurotoxicity and Grade 2 neurotoxicity (specific scale), respectively, were observed in 4 patients and 7 patients receiving GEMOX-1 and in 7 patients and 1 patient receiving GEMOX-2. CONCLUSIONS: Gemcitabine-oxaliplatin combination therapy is feasible in patients with advanced HCC. The GEMOX-1 regimen was tolerated better than the GEMOX-2 regimen. Currently, the GEMOX-1 regimen is being evaluated in a Phase II study in previously untreated patients with HCC.

Adult↗
PubMed2002

Polymorphonuclear neutrophils are a source of hepatocyte growth factor in patients with severe alcoholic hepatitis.

BACKGROUND/AIMS: Hepatocyte growth factor (HGF) is a pleiotropic cytokine involved in liver regeneration. Plasma HGF levels correlate with survival and hepatocyte proliferation in alcoholic hepatitis (AH). As AH is accompanied by inflammation, neutrophilia and polymorphonuclear neutrophil (PMN) infiltration of the liver, we postulated that PMN could be a source of HGF in such patients. METHODS: We studied 25 patients with severe AH in comparison with 20 alcoholic cirrhotic patients without AH and 20 healthy controls; the impact of a 28-day course of corticosteroids was evaluated in patients with AH. RESULTS: On day 0, HGF plasma and homogenized liver tissue levels were markedly increased in AH patients as compared to controls. The role of PMN in HGF production during AH was confirmed by a significantly higher ex-vivo HGF production capacity of lipopolysaccharide-stimulated blood PMN from AH patients relative to both control groups. Formyl-Methionyl-Leucyl-Phenylalanine-induced PMN release of HGF (degranulation conditions) was also higher in AH patients. In this setting, we found that HGF release by PMN ex vivo correlated strongly with HGF plasma levels, and that the degree of hepatic PMN correlated strongly with hepatic HGF levels. HGF plasma levels and ex-vivo HGF release by PMN were unaffected by steroid therapy. CONCLUSIONS: These findings suggest that, by releasing HGF, PMN could participate in liver regeneration during severe alcoholic hepatitis.

Adrenal Cortex Hormones↗
PubMed2002

Ethanol-induced inhibition of cytokine release and protein degranulation in human neutrophils.

Ethanol impairs immune responses in humans and animal models, in vivo and in vitro. In particular, ethanol inhibits some key functions of human polymorphonuclear neutrophils (PMN). We investigated the impact of ethanol on cytokine production by highly purified PMN. In a time- and concentration-dependent manner, ethanol inhibited the production of interleukin (IL)-8 protein and mRNA and also hindered tumor necrosis factor alpha (TNF-alpha) release by modulating the expression of the TNF-alpha-converting enzyme involved in TNF-alpha shedding. This disruption of PMN cytokine release by ethanol may contribute to the increased risk of infection in alcoholic patients. Degranulation of hepatocyte growth factor (HGF) was also impaired by a clinically relevant ethanol concentration (0.8%), an action that may delay the repair of alcoholic liver damage. These findings suggest that ethanol may modulate three major cytokines involved in alcoholic liver diseases, IL-8, TNF-alpha, and HGF, via three different mechanisms.

Cell Degranulation↗
PubMedDate not supplied

The potential of exosomes in immunotherapy of cancer.

Dendritic-cell-derived exosomes (DEX) secreted after dendritic cell loading with tumor peptides were found to mediate tumor rejection in mice. This observation prompted us to demonstrate that MHC class I/peptide complexes harbored onto exosomal membranes were capable of priming cytotoxic T cells and to mediate rejection of tumors expressing the relevant antigens. Moreover, DEX also promote NK cell activation in immunocompetent mice and NK cell-dependent antitumor effects. The first Phase I trial using DEX to immunize melanoma patients revealed the feasibility of DEX production in stage IV melanoma, their safety in long-term follow up and their bioactivity in vivo.

Animals↗
PubMedDate not supplied

[5-FU, folinic acid and cisplatin (LV5FU2-P) for unresectable pancreatic cancer].

AIM: To prospectively evaluate efficacy and tolerance of the 5-fluorouracil + folinic acid + cisplatin (LV5FU2-P) combination in the treatment of unresectable pancreatic carcinoma. PATIENTS AND METHODS: Between March 1998 and June 2000, 35 patients, mean age 61 years (37-75), with advanced (n=2) or metastatic (n=33) pancreatic cancer and initial performance status (WHO) of 0 (n=9), 1 (n=14) or 2 (n=12) were enrolled in the study. Two consecutive groups of patients were treated twice monthly, the first group (n=19) received the LV5FU2 regimen: a 2 hour-infusion of leucovorin 200 mg/m(2), 5-FU bolus 400 mg/m(2), followed by 22-hour continuous infusion of 5-FU 600 mg/m(2) on 2 consecutive days and cisplatin 50 mg/m(2) on day 2. The second group (n=16) received a simplified schedule with bolus leucovorin 40 mg/m(2), 5-FU bolus 400 mg/m(2) on day 1, followed by 5-FU 2400 mg/m(2) 48-hour infusion and cisplatin 50 mg/m(2) on day 2. Clinical symptoms and performance status were monitored together with weight changes. Tumor assessment was performed every 2 months. RESULTS: Three patients (9%) exhibited grade 4 neutropenia and grade 3 toxicity occurred in 31% of the patients (neutropenia: n=3, thrombocytopenia: n=1, vomiting: n=3, mucositis: n=3, diarrhea: n=1). There were no treatment-related deaths. Objective response was observed in 10 patients (29%, 95% confidence interval: 20-40%) including one complete response. Median progression-free survival and overall survival were 4.5 and 9 months, respectively. Six-months and 1-year survival rates were 70% and 25%, respectively. Weight gain was observed in 40% of the patients and performance status improved in 50%. CONCLUSION: LV5FU2-P regimen is active and well tolerated. It should be compared to gemcitabine as a first line therapy in advanced and metastatic pancreatic cancer.

Adenocarcinoma↗