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In a few years, oxaliplatin became a standard treatment of colorectal cancer not only in metastatic situation but also in the adjuvant setting. In the others gastro-intestinal malignancies such as oesophageal, stomach, pancreatic, liver and biliary tract cancers, the effectiveness of the current chemotherapies is unfortunately most often disappointing. Several teams thus decided to evaluate oxaliplatin, essentially in polychemotherapy regimens and sometimes in combination with radiotherapy. Many clinical trials are in progress, others will begin soon. Nevertheless, the results of the first studies already presented are promising, especially the gemcitabine and oxaliplatin combination on 2 days schedule in treating patients with advanced pancreatic, biliary tract and the fluoropyrimidine and oxaliplatin in treating patients with advanced gastric 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.

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.

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.

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.

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.

Background: Combination chemotherapy with continuous 5-fluorouracil (5-FU) and cisplatin in a monthly regimen is one of the standard treatments for advanced gastric carcinoma. This study evaluated the new LV5FU2-P regimen, designed to improve efficacy and tolerance of the 5-FU plus cisplatin combination., Patients and Methods: Forty-three patients with advanced or metastatic gastroesophageal junction or gastric carcinoma were prospectively included in the study. They were treated every 14 days with cisplatin 50 mg/m(2) on day 2 plus folinic acid 200 mg/m(2)/day as a 2-h intravenous (i.v.) infusion on days 1 and 2, plus bolus 5-FU 400 mg/m(2)/day on days 1 and 2, plus continuous 5-FU 600 mg/m(2)/day as a 22-h i.v. infusion on days 1 and 2. Ten patients received a simplified regimen (folinic acid 40 mg/m(2) day 1 + bolus 5-FU 400 mg/m(2) day 1 + continuous 5-FU 2400 mg/m(2) on days 1 and 2 with cisplatin 50 mg/m(2) on day 2)., Results: All the patients were assessable for response and 42 for toxicity. One patient achieved a complete response and 15 a partial response, for an overall response rate of 37.2% [95% confidence interval (CI) 22.1% to 52.3%]. The median progression-free survival was 7.2 months (95% CI 5.4-10.9) and the overall survival was 13.3 months (95% CI 10.1-16.4). There were no treatment-related deaths. Hematological and gastrointestinal toxicities were the most common severe toxicities., Conclusions: LV5FU2-P is an active and well tolerated regimen in the treatment of advanced gastroesophageal junction or gastric carcinomas. It warrants evaluation comparatively with other active regimens.

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.

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.

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., (Copyright 2003 American Cancer Society.)

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.

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.

To improve the efficacy and tolerance of the 5-fluorouracil (5-FU)/cisplatin combination in metastatic esophageal cancer, we designed a new therapeutic schedule, the HLFP regimen. 42 patients with metastatic oesophageal adenocarcinoma (n=10) or squamous cell carcinoma (n=32) were prospectively enrolled in the study. All had bidimensionally measurable disease. The HLFP regimen consisted of twice-monthly oral administration of hydroxyurea 1 g/m(2) on days 0, 1 and 2; a 2-h infusion of leucovorin 200 mg/m(2) and a bolus of 5-FU 400 mg/m(2) followed by a 22-h infusion of 5-FU 600 mg/m(2) on days 1 and 2; and, every two cycles, 80 mg/m(2) cisplatin on day 3. Relief of dysphagia and other symptoms were monitored, together with body weight changes. Major objective responses were observed in 24 patients (57%, 95% Confidence Interval (CI): 42-72%), including four complete responses (10%). The median progression-free survival and overall survival times were 8 and 12.7 months, respectively. Weight gain was observed in 48% of patients, and dysphagia improved in 76%. Grade 3-4 toxicity occurred in 40% of patients, with grade 4 neutropenia in 12% and grade 3 thrombocytopenia, vomiting and diarrhoea in 7-9% of patients. There were no treatment-related deaths. These results suggest that the HLFP regimen is an active and well-tolerated chemotherapy for metastatic oesophageal carcinoma.

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.

THE SITUATION: With around 35.000 new cases per year and a 40% mortality rate, colorectal cancer is a real problem of health care in France. Chemotherapy for metastatic disease has completely changed during the ten last years with the emergence of promising new drugs such as oxaliplatin and irinotecan. Oral 5-FU prodrugs have also shown an interesting efficacy in this setting., Results: Showed increased response rate, progression free survival with both drugs, and overall survival, only with the irinotecan-based regimen. Moreover, after aggressive first-line chemotherapy, some patients can undergo surgical resection of the metastases, initially considered as unresectable. We still do not know if these aggressive first-line therapies should be proposed to all metastatic patients or only to a selected subgroup. The best strategies remain to be evaluated., In the Setting of Adjuvant Chemotherapy: Of colorectal cancer, a 6-month 5-FU/folinic acid postoperative chemotherapy is actually the standard for the management of patients with positive lymph nodes (stage III). In stage II patients the benefit of such treatment remains controversial. The benefit of using oxaliplatin or irinotecan in association with 5-FU/folinic acid as adjuvant therapy is under investigation., Conclusion: In this 21st century, chemotherapy has a major place in the therapeutic management of colorectal cancer patients.

Background/aims: Several observations point to an important role of interactions between polymorphonuclear neutrophils and cytokines in severe alcoholic hepatitis. The polymorphonuclear neutrophil activation status and the local and systemic pro- and anti-inflammatory cytokine responses were quantified. The effect of corticosteroids, widely used in this setting, was evaluated using these parameters., Methods: We studied blood polymorphonuclear neutrophil functions in terms of L-selectin and beta2-integrin expression, H2O2 production and IL-8 and tumor necrosis factor alpha synthesis capacity. We also measured IL-8, tumor necrosis factor alpha and IL-10 plasma and liver tissue levels. Fifteen patients with alcoholic hepatitis were compared to 15 patients with alcoholic cirrhosis without alcoholic hepatitis, and to 10 healthy volunteers. The impact of a 28-day course of corticosteroids on blood neutrophils activation status and cytokine levels was evaluated in patients with alcoholic hepatitis., Results: Blood polymorphonuclear neutrophils were activated, as shown by increased H2O2 production (48+/-6 vs 29+/-6 MFI in healthy controls), and decreased L-selectin expression (300+/-61 vs 449+/-59 in healthy controls). Upon stimulation, polymorphonuclear neutrophils synthesized large amounts of IL-8 (21.7+/-9.2 ng/ml vs 8.8+/-10 ng/ml in healthy controls) and tumor necrosis factor alpha (524+/-132 pg/ml vs 79+/-144 pg/ml in healthy controls). Tumor necrosis factor alpha and IL-8 plasma and tissue levels were markedly increased as IL-10 was barely detectable in alcoholic hepatitis patients, compared to cirrhotic patients and healthy controls. During steroid therapy, plasma levels of the pro-inflammatory cytokine IL-8 fell as early as day 14, while levels of the anti-inflammatory cytokine IL-10 increased on day 21. Finally, polymorphonuclear neutrophil functions returned to normal after treatment., Conclusion: Severe alcoholic hepatitis appears to be associated with polymorphonuclear neutrophil activation and an imbalance between pro- and anti-inflammatory cytokines; during steroid therapy a normalization of these parameters was observed.

We studied the performances of the 17b-estradiol determination with the Kryptor System (Cis Bio international), in assisted medical procreation cycles. The detection is based on Trace technology. We compared this method with Estradiol-6 method on ACS-180 (Bayer Diagnostics). The Kryptor method is sensitive, has a good precision and accuracy. Comparison with ACS-180 showed a good correlation but results were much higher. Patients under stimulation for assisted procreation were followed by the two methods. The results were close to those obtained with ACS-180 but significantly higher. Thus it was necessary to define the levels which have to be reached before ovulation induction.