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T Tursz

Publications and source records attributed to T Tursz.

At least 19 recordsLinked to original sources
PubMed2003

Recombinant adenovirus shedding after intratumoral gene transfer in lung cancer patients.

We conducted two phase 1 trials of direct intratumoral injection of a recombinant E1E3-deleted adenovirus (AdR) encoding either the bacterial enzyme beta-galactosidase (Ad.RSVbetagal) or interleukin 2 (IL2, AdTG5327) into primary nonsmall-cell lung cancers of 21 patients. We report here virus shedding and the duration of virus expression in the tumor after intrabronchial injection of 10(7), 10(8) or 10(9) PFU of adenovirus. The infectious AdR and the viral DNA were detected in PBL, plasma, stool and aerodigestive samples in a dose-dependent manner, since cell cultures and PCRs were found to be positive mainly for samples from patients who received the highest AdR dose (10(9) PFU). We detected beta-galactosidase activity in the tumor biopsy samples of 66% of the patients, seemingly dose related, and only low levels of IL2 mRNA could be detected in tumor biopsy samples. E1 sequences were not detected by PCR in any of the PBL and bronchial samples collected after virus delivery, except in one patient. In this patient, E1 sequences were detected in PBL as well as in tumor biopsy samples collected at days 8, 30 and 60 and were correlated with longer beta-galactosidase expression in tumor samples. PBL tested before and after virus delivery contained both E1 sequences indicating that they did not result from replication-competent adenovirus (RCA) E1 sequences present in the inoculum. In addition, only on the day of the injection was Ad.RSVbetagal also detected in E1-positive PBL, indicating that virus replication in blood was very unlikely.

Adenoviridae↗
PubMed2002

Patterns of failure in a randomized trial of adjuvant chemotherapy in postmenopausal patients with early breast cancer treated with tamoxifen.

BACKGROUND: We studied the effect of adjuvant anthracycline-based chemotherapy in postmenopausal patients with resected early breast cancer treated with adjuvant tamoxifen. PATIENTS AND METHODS: The trial included 835 patients with either axillary lymph node involvement, or tumors with histological grade II or III. They were randomized after local surgery to receive either tamoxifen (TAM group) or tamoxifen plus chemotherapy (TAM-CT group) consisting of six courses of 5-fluorouracil, doxorubicin and cyclophosphamide (FAC), or 5-fluorouracil, epidoxorubicin and cyclophosphamide (FEC). Radiotherapy was given after completion of adjuvant chemotherapy in the TAM-CT group and after surgery in the TAM group. RESULTS: The 5-year disease-free survival (DFS) rates were 73% in the TAM group and 79% in the TAM-CT group (log-rank test, P = 0.06). The 5-year overall survival rates were 82% and 87%, respectively (P = 0.06). The 5-year distant metastasis rates were 22% and 16% (P = 0.02), and the 5-year local recurrence rates were 6% and 4%, respectively (P = 0.23). There were no significant differences for contralateral breast cancer or other new primary malignancies. Chemotherapy tended to be more effective for patients who had tumors without estrogen receptors (trend test, P = 0.05). CONCLUSIONS: Anthracycline-based chemotherapy administered to postmenopausal patients receiving adjuvant tamoxifen gave a borderline significant benefit on overall and DFS, mainly by a reduction in distant metastases. Delaying radiotherapy after six courses of chemotherapy did not affect local control after up to 10 years of follow-up.

Aged↗
PubMed2001

Dendritic cell maturation overrules H-2D-mediated natural killer T (NKT) cell inhibition: critical role for B7 in CD1d-dependent NKT cell interferon gamma production.

Given the broad expression of H-2 class Ib molecules on hematopoietic cells, antigen presentation pathways among CD1d expressing cells might tightly regulate CD1d-restricted natural killer T (NKT) cells. Bone marrow-derived dendritic cells (BM-DCs) and not adherent splenocytes become capable of triggering NK1.1(+)/T cell receptor (TCR)(int) hepatic NKT cell activation when (a) immature BM-DCs lack H-2D(b)-/- molecules or (b) BM-DCs undergo a stress signal of activation. In such conditions, BM-DCs promote T helper type 1 predominant CD1d-restricted NKT cell stimulation. H-2 class Ia-mediated inhibition involves more the direct H-2D(b) presentation than the indirect Qa-1(b) pathway. Such inhibition can be overruled by B7/CD28 interactions and marginally by CD40/CD40L or interleukin 12. These data point to a unique regulatory role of DCs in NKT cell innate immune responses and suggest that H-2 class Ia and Ib pathways differentially control NKT cell recognition of DC antigens.

Animals↗
PubMed2001

Tumor-derived exosomes are a source of shared tumor rejection antigens for CTL cross-priming.

The initiation of T-cell-mediated antitumor immune responses requires the uptake and processing of tumor antigens by dendritic cells and their presentation on MHC-I molecules. Here we show in a human in vitro model system that exosomes, a population of small membrane vesicles secreted by living tumor cells, contain and transfer tumor antigens to dendritic cells. After mouse tumor exosome uptake, dendritic cells induce potent CD8+ T-cell-dependent antitumor effects on syngeneic and allogeneic established mouse tumors. Therefore, exosomes represent a novel source of tumor-rejection antigens for T-cell cross priming, relevant for immunointerventions.

Animals↗
PubMed2000

Loss of heterozygosity, allele silencing and decreased expression of p73 gene in breast cancers: prevalence of alterations in inflammatory breast cancers.

The p73 gene is a p53 homologue located at 1p36-33, a region submitted to deletions in breast cancer (BC) and putatively imprinted. To study whether p73 was associated with breast carcinogenesis, loss of heterozygosity (LOH), allele expression and transcript levels were assessed in 59 BC, including 39 BC presenting no inflammatory symptoms (NBC) and 20 inflammatory BC (IBC). IBC is a rare but aggressive form of cancer with a very poor prognosis. Normal breast epithelium (BE) and lymphocytes from patients were used as controls. StyI polymorphism generating GC and/or AT alleles was used to select 22 heterozygous patients. p73 LOH was significantly higher in IBC than in NBC [five of eight cases (62%) versus two of 14 cases (14%); Fisher's exact test, P=0.05]. p73 was biallelically expressed in all BE. In contrast, 12 of 16 (75%) BC were monoallelically expressed, showing that allele silencing was significantly associated with breast carcinogenesis (P=0.012), AT being the preferential silent allele (10 out of 12 tumours). p73 mRNA levels in NBC and IBC were two- and threefold lower than in BE, respectively, suggesting that decreased expression could be related to tumour aggressiveness. In conclusion, LOH, allele silencing and decreased expression of the p73 gene may play a role in breast carcinogenesis.

Alleles↗
PubMed2000

Longitudinal follow-up of cellular and humoral immunity induced by recombinant adenovirus-mediated gene therapy in cancer patients.

Replication-defective adenoviruses are arousing growing interest as both gene therapy and vaccine vectors. In a phase I clinical trial designed to evaluate the feasibility and tolerance of recombinant adenovirus (rAd)mediated gene transfer, we previously demonstrated that a single intratumoral injection of 10(9) PFU of rAd encoding the beta-galactosidase protein (Ad-beta-Gal) induced strong short-term (1-3 months) humoral, helper (Th1 type) and cytotoxic T cell responses specific for the transgene product in patients with advanced lung cancer. The purpose of the present study was to evaluate the persistence of long-lasting immunity to the transgene protein and in parallel, to assess patient immunocompetence revealed by responses to recall antigens (tetanus toxoid, purified protein derivative), viral pathogens (Epstein-Barr virus, influenza virus), and allogeneic antigens in mixed lymphocytic reactions. The beta-Gal-specific proliferative response declined rapidly in patients with progressive disease, as did responses to the other antigens. In contrast, a long-lasting proliferative response to beta-gal was maintained in an immunocompetent patient in complete remission 2 years after an injection of 108 PFU of Ad-beta-Gal. Anti-beta-Gal humoral (IgG and IgA) responses persisted notably, as did responses to TT and poliomyelytic antigens. While T cell effector cytotoxic responses specific for the viral peptides plummeted, the frequency of anti-beta-Gal CTL precursors remained particularly high, thus attesting to major immunization. Despite the impact of both advanced disease and chemotherapy on immunocompetence, we show the long-term persistence of immunity to the transgene protein vectorized by rAd.

Adenoviridae↗
PubMed2000

p53-dependent G2 arrest associated with a decrease in cyclins A2 and B1 levels in a human carcinoma cell line.

In vivo transfer of wild-type (wt) p53 gene via a recombinant adenovirus has been proposed to induce apoptosis and increase radiosensitivity in several human carcinoma models. In the context of combining p53 gene transfer and irradiation, we investigated the consequences of adenoviral-mediated wtp53 gene transfer on the cell cycle and radiosensitivity of a human head and neck squamous cell carcinoma line (SCC97) with a p53 mutated phenotype. We showed that ectopic expression of wtp53 in SCC97 cells resulted in a prolonged G1 arrest, associated with an increased expression of the cyclin-dependent kinase inhibitor WAF1/p21 target gene. A transient arrest in G2 but not in G1 was observed after irradiation. This G2 arrest was permanent when exponentially growing cells were transduced by Ad5CMV-p53 (RPR/INGN201) immediately after irradiation with 5 or 10 Gy. Moreover, levels of cyclins A2 and B1, which are known to regulate the G2/M transition, dramatically decreased as cells arrived in G2, whereas maximal levels of expression were observed in the absence of wtp53. In conclusion, adenoviral mediated transfer of wtp53 in irradiated SCC97 cells, which are mutated for p53, appeared to increase WAF1/p21 expression and decrease levels of the mitotic cyclins A2 and B1. These observations suggest that the G2 arrest resulted from a p53-dependent premature inactivation of the mitosis promoting factor.

Adenoviridae↗
PubMed2000

Immune response to recombinant adenovirus in humans: capsid components from viral input are targets for vector-specific cytotoxic T lymphocytes.

We previously demonstrated that a single injection of 10(9) PFU of recombinant adenovirus into patients induces strong vector-specific immune responses (H. Gahéry-Ségard, V. Molinier-Frenkel, C. Le Boulaire, P. Saulnier, P. Opolon, R. Lengagne, E. Gautier, A. Le Cesne, L. Zitvogel, A. Venet, C. Schatz, M. Courtney, T. Le Chevalier, T. Tursz, J.-G. Guillet, and F. Farace, J. Clin. Investig. 100:2218-2226, 1997). In the present study we analyzed the mechanism of vector recognition by cytotoxic T lymphocytes (CTL). CD8(+) CTL lines were derived from two patients and maintained in long-term cultures. Target cell infections with E1-deleted and E1-plus E2-deleted adenoviruses, as well as transcription-blocking experiments with actinomycin D, revealed that host T-cell recognition did not require viral gene transcription. Target cells treated with brefeldin A were not lysed, indicating that viral input protein-derived peptides are associated with HLA class I molecules. Using recombinant capsid component-loaded targets, we observed that the three major proteins could be recognized. These results raise the question of the use of multideleted adenoviruses for gene therapy in the quest to diminish antivector CTL responses.

Adenoviridae↗
PubMed2000

Randomized phase III study comparing conventional-dose doxorubicin plus ifosfamide versus high-dose doxorubicin plus ifosfamide plus recombinant human granulocyte-macrophage colony-stimulating factor in advanced soft tissue sarcomas: A trial of the European Organization for Research and Treatment of Cancer/Soft Tissue and Bone Sarcoma Group.

PURPOSE: This randomized multicenter study was designed to compare the activity of a high-dose doxorubicin-containing chemotherapy regimen with a conventional standard-dose regimen in adult patients with advanced soft tissue sarcomas (ASTS). PATIENTS AND METHODS: Between 1992 and 1995, 314 patients were randomized to receive a standard-dose regimen (arm A), containing doxorubicin (50 mg/m(2) on day 1) and ifosfamide (5 g/m(2) on day 1), or an intensified regimen (arm B), combining doxorubicin (75 mg/m(2) on day 1), the same ifosfamide dose, and recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF; sargramostim, 250 microgram/m(2) on days 3 to 16); all courses were repeated every 3 weeks. RESULTS: The median age of the 294 eligible patients was 50 years. They received a median of five chemotherapy cycles. The median dose and relative doxorubicin dose-intensity achieved were 245 mg and 97% in arm A and 360 mg and 99% in arm B, respectively. Thirty-eight percent and 23% of patients presented with leiomyosarcomas and liver metastases, respectively. Objective responses were observed in 31 (21%) of 147 assessable patients in arm A and in 31 (23.3%) of 133 in arm B (P =.65). No change was observed in 41.6% and 46.2% of patients in arm A and B, respectively. Progression-free survival (PFS) was significantly longer in the intensive arm (P =.03). The median duration of the time to progression was 19 weeks in the conventional arm and 29 weeks in the intensified arm. There was no difference in overall survival (P =.98) between the two therapeutic arms. Toxicities were manageable in both arms. A grade 3/4 neutropenia and infection occurred in 92% and 4.6% of patients in arm A, respectively, and in 90% and 16.6% in arm B, respectively. Grade 3/4 thrombocytopenia was more frequent in arm B. CONCLUSION: The use of rhGM-CSF allowed safe escalation of chemotherapy doses. Despite a 50% increase of the doxorubicin dose-intensity, the high-dose regimen failed to demonstrate any impact on survival in patients with ASTS. The low complete response rate, the high incidence of leiomyosarcomas, and liver metastases may in part explain these results. However, the lengthening of the PFS in the intensive arm, because of the quality of stable disease and inappropriate tumor evaluation policies that potentially lead to an underestimation of antitumor activity, does not definitively refute the use of a high-dose chemotherapy regimen in selected patients with ASTS.

Adult↗
PubMed1999

Evidence of LMP1-TRAF3 interactions in glycosphingolipid-rich complexes of lymphoblastoid and nasopharyngeal carcinoma cells.

Latent membrane protein 1 (LMP1) is an Epstein-Barr virus (EBV) protein expressed in EBV-transformed B lymphocytes and in approximately 50% of nasopharyngeal carcinomas (NPCs). LMP1 signaling involves several cellular signaling intermediates, especially TNF receptor-associated factors (TRAFs). We have shown previously that LMP1 is highly concentrated in a cell fraction called glycosphingolipid-rich membrane complexes (GSL complexes). We report here that parallel accumulation of LMP1 and TRAF3, but not TRAF1 or TRADD, was observed in GSL complexes from lymphoblastoid and LMP1-positive NPC cells. In contrast, TRAF3 was not concentrated in GSL complexes from LMP1-negative cells. Binding of LMP1 and TRAF3 in GSL complexes was demonstrated in lymphoblastoid and NPC cells, by co-immunoprecipitation with both anti-LMP1 and anti-TRAF3 antibodies.

Animals↗
PubMed1999

Control of apoptosis in Epstein Barr virus-positive nasopharyngeal carcinoma cells: opposite effects of CD95 and CD40 stimulation.

The expression and function of CD95 and CD40 were investigated in malignant cells from EBV-positive undifferentiated nasopharyngeal carcinomas (NPCs). Large amounts of CD95 and CD40 expression were detected in 15 of 16 EBV-positive NPC specimens. In contrast, CD95 was not detected in two biopsies from patients with EBV-negative differentiated NPCs. We tested whether the CD95 apoptotic pathway was functional in NPC cells by treating two EBV-positive NPC tumor lines in vitro with a CD95 agonist. In both cases, NPC cells were extremely susceptible to CD95-mediated apoptosis, despite strong constitutive expression of Bcl-x. Combined CD40 and CD95 stimulation was used to investigate the possible anti-apoptotic activity mediated by CD40. The CD40 receptor was activated by incubating NPC cells with murine L cells producing CD154, the CD40 ligand. This treatment resulted in a strong inhibition of CD95-related cytotoxicity. Such an anti-apoptotic effect of CD40 is well known for B lymphocytes, but has not previously been reported for epithelial cells. These data suggest that NPC tumor-infiltrating lymphocytes, which often produce the CD40 ligand in situ, may increase the survival of malignant cells, thereby enhancing tumor growth in patients.

Adolescent↗
PubMed1999

Dendritic cells directly trigger NK cell functions: cross-talk relevant in innate anti-tumor immune responses in vivo.

Cytotoxic T lymphocytes and natural killer cells are essential effectors of anti-tumor immune responses in vivo. Dendritic cells (DC) 'prime' tumor antigen-specific cytotoxic T lymphocytes; thus, we investigated whether DC might also trigger the innate, NK cell-mediated anti-tumor immunity. In mice with MHC class I-negative tumors, adoptively transferred- or Flt3 ligand-expanded DC promoted NK cell-dependent anti-tumor effects. In vitro studies demonstrated a cell-to-cell contact between DC and resting NK cells that resulted in a substantial increase in both NK cell cytolytic activity and IFN-gamma production. Thus, DC are involved in the interaction between innate and adaptive immune responses.

Adoptive Transfer↗
PubMed1999

Liver metastases from extremity soft tissue sarcoma.

Liver involvement by soft tissue sarcoma is an unfavorable prognostic factor for survival. Complete resection of liver metastases can bring improvement in selected patients, but chemotherapy remains the only palliative treatment option for most. Anecdotal long-term survival of patients with unresectable liver metastases treated with systemic chemotherapy has been reported, such as the patient presented here.

Combined Modality Therapy↗
PubMed1999

Combination interleukin-2 and doxorubicin in advanced adult solid tumors: circumvention of doxorubicin resistance in soft-tissue sarcoma?

Based on the likelihood of antitumor interactions between cytokines and cytotoxic drugs, we designed a pilot study to evaluate feasibility, clinical, pharmacologic, and immunologic effects of concomitantly administered subcutaneous (SQ) recombinant interleukin-2 (r-IL-2) and doxorubicin (ADR) in patients with advanced solid tumors (AST). Patients received one injection of ADR alone (70 mg/m2) and 3 weeks later a combination of r-IL-2 (18 MIU/m2 days 1-5 s.q.) and ADR at the same dose either 3-4 h after the first r-IL-2 injection (arm 1) or 2 days after the last r-IL-2 injection (arm 2). The same combination was repeated every 4 weeks according to the evolution of the disease. Pharmacokinetics were assessed over 48 h after injection of ADR alone and after the first ADR-IL-2 cycle and immunologic monitoring at days 1 and 8 of the first ADR-IL-2 cycle. Tumors were measured at baseline, after ADR alone, and after each ADR-IL-2 cycle until progression. Twenty-one adult patients with various AST including 14 soft-tissue sarcomas (STS) entered the study, 11 in arm 1 and 10 in arm 2. All patients were heavily pretreated; 16 had received an anthracycline-containing chemotherapy regimen. Eleven patients were ADR refractory and 1 ADR resistant. Grade 4 neutropenia occurred in 28, 82, and 40% of patients after ADR alone, ADR-IL-2 in arm 1 and ADR-IL-2 in arm 2, respectively. Mucitis was higher in arm 1 (7 of 11 patients) compared with arm 2 (0 of 10) and ADR alone (0 of 21). SQ injections of r-IL-2 did not affect ADR pharmacokinetics. ADR injection in arm 1 prevented IL-2-induced lymphocyte rebounds in all patients but did not alter qualitatively non-major histocompatibility complex-restricted cytotoxicity. There was no response after ADR alone. Two patients, one in each arm, experienced a prolonged (8 and 5 months) objective response after ADR-IL-2. Both had ADR-refractory STS with a local relapse and metastatic metastases. Interestingly, both patients had unusually elevated TNF-alpha levels before and after the first ADR cycle. Combination ADR-IL-2, although toxic, is feasible and manageable with routine clinical support. r-IL-2 enhanced ADR hematologic and extrahematologic toxicities. The two objective responses observed in these heavily pretreated patients refractory to ADR supports the hypothesis of a modulation of ADR resistance, possibly mediated by means of a mechanism involving TNF-alpha. Elevated baseline TNF-alpha levels could be predictive of response to ADR-IL-2 and deserves further investigation.

Adult↗
PubMed1999

Prognostic factors for the outcome of chemotherapy in advanced soft tissue sarcoma: an analysis of 2,185 patients treated with anthracycline-containing first-line regimens--a European Organization for Research and Treatment of Cancer Soft Tissue and Bone Sarcoma Group Study.

PURPOSE: A total of 2,185 patients with advanced soft tissue sarcomas who had been treated in seven clinical trials investigating the use of doxorubicin- or epirubicin-containing regimens as first-line chemotherapy were studied in this prognostic-factor analysis. PATIENTS AND METHODS: Overall survival time (median, 51 weeks) and response to chemotherapy (26% complete response or partial response) were the two end points. The cofactors were sex; age; performance status; prior therapies; the presence of locoregional or recurrent disease; lung, liver, and bone metastases at the time of entry onto the trial; long time period between the initial diagnosis of sarcoma and entry onto the study; and histologic type and grade. RESULTS: Univariate analyses showed (a) a significant, favorable influence of good performance status, young age, and absence of liver metastases on both survival time and response rate, (b) a significant, favorable influence of low histopathologic disease grade on survival time, despite a significantly lower response rate, (c) increased survival time for patients with a long time period between the initial diagnosis of sarcoma and entry onto the study, despite equivalent response rates, and (d) increased survival time with liposarcoma or synovial sarcoma, a decreased survival time with malignant fibrous histiocytoma, a lower response rate with leiomyosarcoma, and a higher response rate with liposarcoma (P < .05 for all log-rank and chi2 tests). The Cox model selected good performance status (P < .0001), absence of liver metastases (P = .0001), low histopathologic grade (P = .0002), long time lapse since initial diagnosis (P = .0004), and young age (P = .0045) as favorable prognostic factors of survival time. The logistic model selected absence of liver metastases (P < .0001), young age (P = .0024), high histopathologic grade (P = .0051), and liposarcoma (P = .0065) as favorable prognostic factors of response rate. CONCLUSION: This analysis demonstrates that for advanced soft tissue sarcoma, response to chemotherapy is not predicted by the same factors as is overall survival time. This needs to be taken into account in the interpretation of trials assessing the value of new agents for this disease on the basis of response to treatment.

Adult↗
PubMed1998

Recombinant human interleukin-2, recombinant human interferon alfa-2a, or both in metastatic renal-cell carcinoma. Groupe Français d'Immunothérapie.

BACKGROUND: Recombinant human interleukin-2 (aldesleukin) and recombinant human interferon alfa can induce notable tumor regression in a limited number of patients with metastatic renal-cell carcinoma. We conducted a multicenter, randomized trial to determine the effect of each cytokine independently and in combination, and to identify patients who are best suited for this treatment. METHODS: Four hundred twenty-five patients with metastatic renal-cell carcinoma were randomly assigned to receive either a continuous intravenous infusion of interleukin-2, subcutaneous injections of interferon alfa-2a, or both. The main outcome measure was the response rate; secondary outcomes were the rates of event-free and overall survival. Predictive factors for response and rapid progression were identified by multivariate analysis. RESULTS: Response rates were 6.5 percent, 7.5 percent, and 18.6 percent (P<0.01) for the groups receiving interleukin-2, interferon alfa-2a, and interleukin-2 plus interferon alfa-2a, respectively. At one year, the event-free survival rates were 15 percent, 12 percent, and 20 percent, respectively (P=0.01). There was no significant difference in overall survival among the three groups. Toxic effects of therapy were more common in patients receiving interleukin-2 than in those receiving interferon alfa-2a. Response to treatment was associated with having metastasis to a single organ and with receiving the combined treatment. The probability of rapid progression of disease was at least 70 percent for patients with at least two metastatic sites, liver metastases, and a period of less than one year between the diagnosis of the primary tumor and the appearance of metastases. CONCLUSIONS: Cytokines are active in a few patients with metastatic renal-cell carcinoma. The higher response rate and longer event-free survival obtained with a combination of cytokines must be balanced against the toxicity of such treatment.

Adjuvants, Immunologic↗