96 resultados para partition in micellar phase


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PURPOSE: This randomized phase II trial evaluated two docetaxel-based regimens to see which would be most promising according to overall response rate (ORR) for comparison in a phase III trial with epirubicin-cisplatin-fluorouracil (ECF) as first-line advanced gastric cancer therapy. PATIENTS AND METHODS: Chemotherapy-naïve patients with measurable unresectable and/or metastatic gastric carcinoma, a performance status <or= 1, and adequate hematologic, hepatic, and renal function randomly received <or= eight 3-weekly cycles of ECF (epirubicin 50 mg/m(2) on day 1, cisplatin 60 mg/m(2) on day 1, and fluorouracil [FU] 200 mg/m(2)/d on days 1 to 21), TC (docetaxel initially 85 mg/m(2) on day 1 [later reduced to 75 mg/m(2) as a result of toxicity] and cisplatin 75 mg/m(2) on day 1), or TCF (TC plus FU 300 mg/m(2)/d on days 1 to 14). Study objectives included response (primary), survival, toxicity, and quality of life (QOL). RESULTS: ORR was 25.0% (95% CI, 13% to 41%) for ECF, 18.5% (95% CI, 9% to 34%) for TC, and 36.6% (95% CI, 23% to 53%) for TCF (n = 119). Median overall survival times were 8.3, 11.0, and 10.4 months for ECF, TC, and TCF, respectively. Toxicity was acceptable, with one toxic death (TC arm). Grade 3 or 4 neutropenia occurred in more treatment cycles with docetaxel (TC, 49%; TCF, 57%; ECF, 34%). Global health status/QOL substantially improved with ECF and remained similar to baseline with both docetaxel regimens. CONCLUSION: Time to response and ORR favor TCF over TC for further evaluation, particularly in the neoadjuvant setting. A trend towards increased myelosuppression and infectious complications with TCF versus TC or ECF was observed.

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Integrative and conjugative elements (ICE) are in some ways parasitic mobile DNA that propagate vertically through replication with the bacterial host chromosome but at low frequencies can excise and invade new recipient cells through conjugation and reintegration (horizontal propagation). The factors that contribute to successful horizontal propagation are not very well understood. Here, we study the influence of host cell life history on the initiation of transfer of a model ICE named ICEclc in bacteria of the genus Pseudomonas. We use time-lapse microscopy of growing and stationary-phase microcolonies of ICEclc bearing cells in combination with physiological staining and gene reporter analysis in stationary-phase suspended cells. We provide evidence that cell age and cell lineage are unlikely to play a role in the decision to initiate the ICEclc transfer program. In contrast, cells activating ICEclc show more often increased levels of reactive oxygen species and membrane damage than nonactivating cells, suggesting that some form of biochemical damage may make cells more prone to ICEclc induction. Finally, we find that ICEclc active cells appear spatially at random in a microcolony, which may have been a selective advantage for maximizing ICEclc horizontal transmission to new recipient species.

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AIM: We investigated the prognostic significance of intraductal carcinoma of the prostate (IDC-P) in biopsies and transurethral resections prior to external beam radiotherapy with or without androgen deprivation. METHODS: Cohort 1 consisted of 118 intermediate risk prostate cancer patients treated by radiotherapy, with biochemical relapse as primary end-point (median follow-up 6.5 years). Cohort 2 consisted of 132 high risk patients, enrolled in a phase III randomised trial (EORTC 22863) comparing radiotherapy alone to radiotherapy with long-term androgen deprivation (LTAD) with clinical progression free survival as primary end-point (median follow-up 9.1 years). Presence of IDC-P was identified after central review. Multivariable regression modelling and Kaplan-Meier analysis were performed with IDC-P as dichotomous variable. RESULTS: IDC-P was a strong prognosticator for early (<36 months) biochemical relapse (HR 7.3; p = 0.007) in cohort 1 and for clinical disease-free survival in both arms of cohort 2 (radiotherapy arm: HR 3.5; p < 0.0001; radiotherapy plus LTAD arm: HR 2.8, p = 0.018). IDC-P retained significance after stratification for reviewed Gleason score in the radiotherapy arm (HR 2.3; p = 0.03). IDC-P was a strong prognosticator for metastatic failure rate (radiotherapy arm: HR 5.3; p < 0.0001; radiotherapy plus LTAD arm: HR 3.6; p = 0.05). CONCLUSIONS: IDC-P in diagnostic samples of patients with intermediate or high risk prostate cancer is an independent prognosticator of early biochemical relapse and metastatic failure rate after radiotherapy. We suggest that the presence of IDC-P in prostate biopsies should routinely be reported.

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We investigated the activity of linezolid, alone and in combination with rifampin (rifampicin), against a methicillin-resistant Staphylococcus aureus (MRSA) strain in vitro and in a guinea pig model of foreign-body infection. The MIC, minimal bactericidal concentration (MBC) in logarithmic phase, and MBC in stationary growth phase were 2.5, >20, and >20 microg/ml, respectively, for linezolid; 0.01, 0.08, and 2.5 microg/ml, respectively, for rifampin; and 0.16, 0.63, >20 microg/ml, respectively, for levofloxacin. In time-kill studies, bacterial regrowth and the development of rifampin resistance were observed after 24 h with rifampin alone at 1x or 4x the MIC and were prevented by the addition of linezolid. After the administration of single intraperitoneal doses of 25, 50, and 75 mg/kg of body weight, linezolid peak concentrations of 6.8, 12.7, and 18.1 microg/ml, respectively, were achieved in sterile cage fluid at approximately 3 h. The linezolid concentration remained above the MIC of the test organism for 12 h with all doses. Antimicrobial treatments of animals with cage implant infections were given twice daily for 4 days. Linezolid alone at 25, 50, and 75 mg/kg reduced the planktonic bacteria in cage fluid during treatment by 1.2 to 1.7 log(10) CFU/ml; only linezolid at 75 mg/kg prevented bacterial regrowth 5 days after the end of treatment. Linezolid used in combination with rifampin (12.5 mg/kg) was more effective than linezolid used as monotherapy, reducing the planktonic bacteria by >or=3 log(10) CFU (P < 0.05). Efficacy in the eradication of cage-associated infection was achieved only when linezolid was combined with rifampin, with cure rates being between 50% and 60%, whereas the levofloxacin-rifampin combination demonstrated the highest cure rate (91%) against the strain tested. The linezolid-rifampin combination is a treatment option for implant-associated infections caused by quinolone-resistant MRSA.

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In this study, we report the identification of two parasite polypeptides recognized by human sera of patients infected with Leishmania major. Isolation and sequencing of the two genes encoding these polypeptides revealed that one of the genes is similar to the L. major cathepsin L-like gene family CPB, whereas the other gene codes for the L. major homologue of the cysteine proteinase a (CPA) of L. mexicana. By restriction enzyme digestion of genomic DNA, we show that the CPB gene is present in multiple copies in contrast to the cysteine proteinase CPA gene which could be unique. Specific antibodies directed against the mature regions of both types expressed in Escherichia coli were used to analyze the expression of these polypeptides in different stages of the parasite's life cycle. Polypeptides of 27 and 40 kDa in size, corresponding to CPA and CPB respectively, were detected at higher level in amastigotes than in stationary phase promastigotes. Purified recombinant CPs were also used to examine the presence of specific antibodies in sera from either recovered or active cases of cutaneous leishmaniasis patients. Unlike sera from healthy uninfected controls, all the sera reacted with recombinant CPA and CPB. This finding indicates that individuals having recovered from cutaneous leishmaniasis or with clinically apparent disease have humoral responses to cysteine proteinases demonstrating the importance of these proteinases as targets of the immune response and also their potential use for serodiagnosis.

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This study examines the effects of a borderline-specific treatment, called general psychiatric management, on emotional change, outcome and therapeutic alliance of an outpatient presenting with borderline personality disorder. Based on the sequential model of emotional processing, emotional states were assessed in a 10-session setting. The case showed an increase in expressions of distress and no change in therapeutic alliance and tended towards general deterioration. Results suggest emotional processing may play a lesser role in general psychiatric management in early phase treatment than previously hypothezised. Copyright © 2015 John Wiley & Sons, Ltd.

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Microsatellites are important highly polymorphic genetic markers dispersed in the human genome. Using a panel of 22 (CA)n repeat microsatellite markers mapped to recurrent breakpoint cluster regions specifically involved in leukemia, we investigated 114 adult leukemias (25 acute lymphocytic leukemia [ALL], 32 acute myeloid leukemia [AML], 36 chronic lymphocytic leukemia [CLL], and 21 chronic myeloid leukemia [CML] in chronic phase) for somatic mutations at these loci. In each patient, DNA from fresh leukemia samples was analyzed alongside normal constitutive DNA from buccal epithelium. We detected loss of heterozygosity (LOH) in 81 of 114 patients (ALL 16/25, AML 25/32, CLL 30/36, CML 10/21). Deletions were most often seen in ALL at 11q23 and 19p13; in AML at 8q22 and 11q23; in CLL at 13q14.3, 11q13, and 11q23; and in CML at 3q26. Only six deletions were reported in 74 karyotypes analyzed, whereas in these same cases, 91 LOH events were detected by microsatellites. Of 26 leukemias with a normal karyotype, 16 nevertheless showed at least one LOH by microsatellite analysis. Replication errors were found in 10 of 114 patients (8.8%). Thus, microsatellite instability is rare in leukemia in contrast to many solid tumors. Our findings suggest that in adult leukemia, LOH may be an important genetic event in addition to typical chromosomal translocations. LOH may point to the existence of tumor suppressor genes involved in leukemogenesis to a degree that has hitherto been underestimated.

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In the plant-beneficial soil bacterium and biocontrol model organism Pseudomonas fluorescens CHA0, the GacS/GacA two-component system upregulates the production of biocontrol factors, i.e. antifungal secondary metabolites and extracellular enzymes, under conditions of slow, non-exponential growth. When activated, the GacS/GacA system promotes the transcription of a small regulatory RNA (RsmZ), which sequesters the small RNA-binding protein RsmA, a translational regulator of genes involved in biocontrol. The gene for a second GacA-regulated small RNA (RsmY) was detected in silico in various pseudomonads, and was cloned from strain CHA0. RsmY, like RsmZ, contains several characteristic GGA motifs. The rsmY gene was expressed in strain CHA0 as a 118 nt transcript which was most abundant in stationary phase, as revealed by Northern blot and transcriptional fusion analysis. Transcription of rsmY was enhanced by the addition of the strain's own supernatant extract containing a quorum-sensing signal and was abolished in gacS or gacA mutants. An rsmA mutation led to reduced rsmY expression, via a gacA-independent mechanism. Overexpression of rsmY restored the expression of target genes (hcnA, aprA) to gacS or gacA mutants. Whereas mutants deleted for either the rsmY or the rsmZ structural gene were not significantly altered in the synthesis of extracellular products (hydrogen cyanide, 2,4-diacetylphloroglucinol, exoprotease), an rsmY rsmZ double mutant was strongly impaired in this production and in its biocontrol properties in a cucumber-Pythium ultimum microcosm. Mobility shift assays demonstrated that multiple molecules of RsmA bound specifically to RsmY and RsmZ RNAs. In conclusion, two small, untranslated RNAs, RsmY and RsmZ, are key factors that relieve RsmA-mediated regulation of secondary metabolism and biocontrol traits in the GacS/GacA cascade of strain CHA0.

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ABSTRACT Poor outcome for glioblastoma patients is largely due to resistance to chemoradiation therapy. While epigenetic inactivation of MGMT mediated DNA repair is highly predictive for benefit from the alkylating agent therapy Temozolomide, additional mechanisms for resistance associated with molecular alterations exist. Furthermore, new concepts in cancer suggest that resistance to treatment may be linked to cancer stem cells that escape therapy and act as source for tumour recurrence. We determined gene expression signatures associated with outcome in glioblastoma patients enrolled in a phase II and phase III clinical trial establishing the new combination therapy of radiation plus concomitant and adjuvant Temozolomide. Correlating stable gene clusters emerging from unsupervised analysis with survival of 42 treated patients identified a number of biological processes associated with outcome. Most prominent, a gene cluster dominated by HOX genes and comprising PROM1, was associated with resistance. PROM1 encodes CD133, a marker for a subpopulation of tumour cells enriched for glioblastoma stem- like cells. The core of this correlated HOX cluster was comprised in the top genes of a "self-renewal signature" defined in a mouse model for MLL-AF9 initiated leukaemia. The association of the HOX gene cluster with tumour resistance was confirmed in two external data sets of 146 malignant glioma As additional resistance factors we identified over-expression of the epidermal growth factor receptor gene, EGFR, while increased gene expression related to biological features of tumour host interaction, including markers for tumour vascular and cell adhesion, and innate immune response, were associated with better outcome. The "self-renewal" signature associated with resistance to the new combination chemoradiation therapy provides first clinical evidence that glioma stem like cells may implicated in resistance in a uniformly treated cohort of glioblastoma patients. This study underlines the need to target the tumour stem cell compartment, and provides some testable hypothesis for biological mechanisms relevant for malignant behaviour of glioblastoma that may be targeted in new treatment approaches. Résumé Le glioblastome, tumeur cérébrale primaire maligne la plus fréquente, est connue pour son mauvais pronostique. Des avancées chimiothérapeutiques récentes avec des agents alkylants comme le témozolomide (TMZ), ont permis une amélioration notable dans la survie de certains patients. Les bénéficiaires ont la caractéristique commune de présenter une particularité génétique, la methylation du MGMT (methylguanine methyltransferase). Néanmoins, d'autres mécanismes de résistance en fonction des aberrations moléculaires existent. Nous avons établi les profils d'expressions génétiques des patients traités par irradiation et TMZ dans des études cliniques de phase II et III. En combinant des méthodes non-supervisées et supervisées, de l'étude de la cohorte des patients traités nous avons découvert des groupes de gènes associés à la survie. Un ensemble de gènes contenant les gènes Hox semble lié au mécanisme de résistance au traitement. Récemment, les gènes Hox ont été décrits comme faisant partie d"une signature d'autorenouvellement (self-renewal) des cellules souches cancéreuses de la leucémie. L'autorenouvellement est un processus grâce auquel les cellules souches se maintiennent tout au long de la vie. Cette association à la résistance est confirmée dans deux autres études indépendantes. Un autre facteur de résistance au traitement est la surexpression du gène EGFR. D'autre part, deux groupes de gènes associés à la relation entre hôte-tumeur tels que les marqueurs des vaisseaux tumoraux et de la réponse immunitaire innée s'avèrent avoir un effet positif sur la survie des patients traités. La découverte de la signature d'autorenouvellement comme facteur de résistance à la nouvelle chimio-radiothérapie offre une preuve clinique que les cellules souches cancéreuses sont impliquées dans la résistance au traitement. If est donc logique de penser que le traitement ciblé contre des cellules souches cancéreuses va dans l'avenir permettre des thérapies anticancéreuses plus performantes.

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Subventricular zone (SVZ) progenitors are a hallmark of the developing neocortex. Recent studies described a novel type of SVZ progenitor that retains a basal process at mitosis, sustains expression of radial glial markers, and is capable of self-renewal. These progenitors, referred to here as basal radial glia (bRG), occur at high relative abundance in the SVZ of gyrencephalic primates (human) and nonprimates (ferret) but not lissencephalic rodents (mouse). Here, we analyzed the occurrence of bRG cells in the embryonic neocortex of the common marmoset Callithrix jacchus, a near-lissencephalic primate. bRG cells, expressing Pax6, Sox2 (but not Tbr2), glutamate aspartate transporter, and glial fibrillary acidic protein and retaining a basal process at mitosis, occur at similar relative abundance in the marmoset SVZ as in human and ferret. The proportion of progenitors in M-phase was lower in embryonic marmoset than developing ferret neocortex, raising the possibility of a longer cell cycle. Fitting the gyrification indices of 26 anthropoid species to an evolutionary model suggested that the marmoset evolved from a gyrencephalic ancestor. Our results suggest that a high relative abundance of bRG cells may be necessary, but is not sufficient, for gyrencephaly and that the marmoset's lissencephaly evolved secondarily by changing progenitor parameters other than progenitor type.

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Engineering of fetal tissue has a high potential for the treatment of acute and chronic wounds of the skin in humans as these cells have high expansion capacity under simple culture conditions and one organ donation can produce Master Cell Banks which can fabricate over 900 million biological bandages (9 x 12cm). In a Phase 1 clinical safety study, cases are presented for the treatment of therapy resistant leg ulcers. All eight patients, representing 13 ulcers, tolerated multiple treatments with fetal biological bandages showing no negative secondary effects and repair processes similar to that seen in 3rd degree burns. Differential gene profiling using Affymetrix gene chips (analyzing 12,500 genes) were accomplished on these banked fetal dermal skin cells compared to banked dermal skin cells of an aged donor in order to point to potential indicators of wound healing. Families of genes involved in cell adhesion and extracellular matrix, cell cycle, cellular signaling, development and immune response show significant differences in regulation between banked fetal and those from banked old skin cells: with approximately 47.0% of genes over-expressed in fetal fibroblasts. It is perhaps these differences which contribute to efficient tissue repair seen in the clinic with fetal cell therapy.

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Limited treatment options are available for implant-associated infections caused by methicillin (meticillin)-resistant Staphylococcus aureus (MRSA). We compared the activity of daptomycin (alone and with rifampin [rifampicin]) with the activities of other antimicrobial regimens against MRSA ATCC 43300 in the guinea pig foreign-body infection model. The daptomycin MIC and the minimum bactericidal concentration in logarithmic phase and stationary growth phase of MRSA were 0.625, 0.625, and 20 microg/ml, respectively. In time-kill studies, daptomycin showed rapid and concentration-dependent killing of MRSA in stationary growth phase. At concentrations above 20 microg/ml, daptomycin reduced the counts by >3 log(10) CFU/ml in 2 to 4 h. In sterile cage fluid, daptomycin peak concentrations of 23.1, 46.3, and 53.7 microg/ml were reached 4 to 6 h after the administration of single intraperitoneal doses of 20, 30, and 40 mg/kg of body weight, respectively. In treatment studies, daptomycin alone reduced the planktonic MRSA counts by 0.3 log(10) CFU/ml, whereas in combination with rifampin, a reduction in the counts of >6 log(10) CFU/ml was observed. Vancomycin and daptomycin (at both doses) were unable to cure any cage-associated infection when they were given as monotherapy, whereas rifampin alone cured the infections in 33% of the cages. In combination with rifampin, daptomycin showed cure rates of 25% (at 20 mg/kg) and 67% (at 30 mg/kg), vancomycin showed a cure rate of 8%, linezolid showed a cure rate of 0%, and levofloxacin showed a cure rate of 58%. In addition, daptomycin at a high dose (30 mg/kg) completely prevented the emergence of rifampin resistance in planktonic and adherent MRSA cells. Daptomycin at a high dose, corresponding to 6 mg/kg in humans, in combination with rifampin showed the highest activity against planktonic and adherent MRSA. Daptomycin plus rifampin is a promising treatment option for implant-associated MRSA infections.

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Introduction: The Thalidomide-Dexamethasone (TD) regimen has provided encouraging results in relapsed MM. To improve results, bortezomib (Velcade) has been added to the combination in previous phase II studies, the so called VTD regimen. In January 2006, the European Group for Blood and Marrow Transplantation (EBMT) and the Intergroupe Francophone du Myélome (IFM) initiated a prospective, randomized, parallel-group, open-label phase III, multicenter study, comparing VTD (arm A) with TD (arm B) for MM patients progressing or relapsing after autologous transplantation. Patients and Methods: Inclusion criteria: patients in first progression or relapse after at least one autologous transplantation, including those who had received bortezomib or thalidomide before transplant. Exclusion criteria: subjects with neuropathy above grade 1 or non secretory MM. Primary study end point was time to progression (TTP). Secondary end points included safety, response rate, progression-free survival (PFS) and overall survival (OS). Treatment was scheduled as follows: bortezomib 1.3 mg/m2 was given as an i.v bolus on Days 1, 4, 8 and 11 followed by a 10-Day rest period (days 12 to 21) for 8 cycles (6 months) and then on Days 1, 8, 15, 22 followed by a 20-Day rest period (days 23 to 42) for 4 cycles (6 months). In both arms, thalidomide was scheduled at 200 mg/Day orally for one year and dexamethasone 40 mg/Day orally four days every three weeks for one year. Patients reaching remission could proceed to a new stem cell harvest. However, transplantation, either autologous or allogeneic, could only be performed in patients who completed the planned one year treatment period. Response was assessed by EBMT criteria, with additional category of near complete remission (nCR). Adverse events were graded by the NCI-CTCAE, Version 3.0.The trial was based on a group sequential design, with 4 planned interim analyses and one final analysis that allowed stopping for efficacy as well as futility. The overall alpha and power were set equal to 0.025 and 0.90 respectively. The test for decision making was based on the comparison in terms of the ratio of the cause-specific hazards of relapse/progression, estimated in a Cox model stratified on the number of previous autologous transplantations. Relapse/progression cumulative incidence was estimated using the proper nonparametric estimator, the comparison was done by the Gray test. PFS and OS probabilities were estimated by the Kaplan-Meier curves, the comparison was performed by the Log-Rank test. An interim safety analysis was performed when the first hundred patients had been included. The safety committee recommended to continue the trial. Results: As of 1st July 2010, 269 patients had been enrolled in the study, 139 in France (IFM 2005-04 study), 21 in Italy, 38 in Germany, 19 in Switzerland (a SAKK study), 23 in Belgium, 8 in Austria, 8 in the Czech republic, 11 in Hungary, 1 in the UK and 1 in Israel. One hundred and sixty nine patients were males and 100 females; the median age was 61 yrs (range 29-76). One hundred and thirty six patients were randomized to receive VTD and 133 to receive TD. The current analysis is based on 246 patients (124 in arm A, 122 in arm B) included in the second interim analysis, carried out when 134 events were observed. Following this analysis, the trial was stopped because of significant superiority of VTD over TD. The remaining patients were too premature to contribute to the analysis. The number of previous autologous transplants was one in 63 vs 60 and two or more in 61 vs 62 patients in arm A vs B respectively. The median follow-up was 25 months. The median TTP was 20 months vs 15 months respectively in arm A and B, with cumulative incidence of relapse/progression at 2 years equal to 52% (95% CI: 42%-64%) vs 70% (95% CI: 61%-81%) (p=0.0004, Gray test). The same superiority of arm A was also observed when stratifying on the number of previous autologous transplantations. At 2 years, PFS was 39% (95% CI: 30%-51%) vs 23% (95% CI: 16%-34%) (A vs B, p=0.0006, Log-Rank test). OS in the first two years was comparable in the two groups. Conclusion: VTD resulted in significantly longer TTP and PFS in patients relapsing after ASCT. Analysis of response and safety data are on going and results will be presented at the meeting. Protocol EU-DRACT number: 2005-001628-35.

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Nilotinib, a novel tyrosine kinase inhibitor (TKI) that inhibits BCR-ABL, the stem cell factor receptor (KIT), and platelet-derived growth factor receptor-alpha (PDGFRα), is approved for the treatment of patients with newly diagnosed Philadelphia chromosome-positive chronic myelogenous leukemia (CML) and those with CML that is imatinib-resistant or -intolerant. Due to its potent inhibition of KIT and PDGFRα--the two tyrosine kinases that are the central oncogenic mechanisms of gastrointestinal stromal tumors (GIST)--nilotinib also has been investigated for potential efficacy and safety in patients with GIST who have progressed on other approved treatments. Initial results have been encouraging, as nilotinib has demonstrated clinical efficacy and safety in a phase I trial as either a single agent or in combination with imatinib, as well as in heavily pretreated patients with GIST in a compassionate use program. In addition, the phase III trial of nilotinib versus best supportive care (with or without a TKI at the investigator's discretion) indicated that nilotinib may have efficacy in some third-line patients. Furthermore, the Evaluating Nilotinib Efficacy and Safety in Clinical Trials (ENEST g1 trial), a phase III randomized, open-label study comparing the safety and efficacy of imatinib versus nilotinib in the first-line treatment of patients with GIST, is currently under way. Other studies with nilotinib either have been initiated or are in development. Based on published and accruing clinical data, nilotinib shows potential as a new drug in the clinician's armamentarium for the management of GIST.

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Background In angioimmunoblastic T-cell lymphoma, symptoms linked to B-lymphocyte activation are common, and variable numbers of CD20(+) large B-blasts, often infected by Epstein-Barr virus, are found in tumor tissues. We postulated that the disruption of putative B-T interactions and/or depletion of the Epstein-Barr virus reservoir by an anti-CD20 monoclonal antibody (rituximab) could improve the clinical outcome produced by conventional chemotherapy. DESIGN AND METHODS: Twenty-five newly diagnosed patients were treated, in a phase II study, with eight cycles of rituximab + chemotherapy (R-CHOP21). Tumor infiltration, B-blasts and Epstein-Barr virus status in tumor tissue and peripheral blood were fully characterized at diagnosis and were correlated with clinical outcome. RESULTS: A complete response rate of 44% (95% CI, 24% to 65%) was observed. With a median follow-up of 24 months, the 2-year progression-free survival rate was 42% (95% CI, 22% to 61%) and overall survival rate was 62% (95% CI, 40% to 78%). The presence of Epstein-Barr virus DNA in peripheral blood mononuclear cells (14/21 patients) correlated with Epstein-Barr virus score in lymph nodes (P<0.004) and the detection of circulating tumor cells (P=0.0019). Despite peripheral Epstein-Barr virus clearance after treatment, the viral load at diagnosis (>100 copy/μg DNA) was associated with shorter progression-free survival (P=0.06). Conclusions We report here the results of the first clinical trial targeting both the neoplastic T cells and the microenvironment-associated CD20(+) B lymphocytes in angioimmunoblastic T-cell lymphoma, showing no clear benefit of adding rituximab to conventional chemotherapy. A strong relationship, not previously described, between circulating Epstein-Barr virus and circulating tumor cells is highlighted.