Publications by authors named "Foss F"

Despite significant advances in stem cell manipulation and post-transplant immunosuppression, chronic graft-versus-host disease (cGVHD) remains a cause of major long-term morbidity in survivors of allogeneic stem cell transplantation. Extracorporeal photopheresis (ECP) is a novel therapeutic intervention which has demonstrated efficacy in patients with refractory acute and chronic GVHD. Clinical responses have been reported in skin and visceral GVHD.

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The residues located at the carboxyl terminus of helix D in interleukin-7 (IL-7) have previously been targeted as important for recruitment and binding to the gamma chain component of the IL-7 receptor (IL-7R). In this study, Trp 143 of helix D was mutated to His, Phe, Tyr and Pro and these mutants, along with a W143A mutant previously described, were studied to determine the effects on activation of DNA synthesis and binding affinity to IL-7R positive 2E8 cells. The W143F and W143Y mutants were similar to wild type IL-7 in their binding properties and retained 85% and 74% of their activating properties, respectively.

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AG957 (NSC 654705) is a tyrphostin tyrosine kinase inhibitor that has been demonstrated previously to induce growth arrest in chronic myelogenous leukemia cells by inhibiting p210(bcr-abl) kinase activity and by stabilizing the association of p210(bcr-abl) kinase with its signaling adaptor molecules, Shc and Grb2. In previous studies, it has been demonstrated that AG957-associated down-regulation of bcr-abl activates the cytochrome c/Apaf-1/caspase-9 pathway and induces apoptosis in chronic myelogenous leukemia blasts and progenitor cells. While AG957 has been purported to have specificity for the p210(bcr-abl) kinase, antiproliferative effects of AG957 in normal T-lymphocytes and bcr-abl negative leukemia cells suggest that other targets, such as c-CBL, may be substrates.

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Background: Large cell transformation in patients with mycosis fungoides (MF) has been well reported in the literature. Although the risk factors have not been clearly elucidated, advanced stage seems to be associated with a higher incidence of transformation. Because MF is a rare disorder, little is known about the influence of other factors such as immunosuppressive therapy in the occurrence of transformation.

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Cutaneous T-cell lymphoma (CTCL) can be associated with painful, pruritic, disfiguring lesions. As part of a multicenter, randomized phase III trial in patients with heavily pretreated advanced and/or recurrent CTCL, the effects of an interleukin-2 receptor-targeted fusion protein, denileukin diftitox (DAB389IL-2, ONTAK), on patient-rated overall quality of life (QOL), skin appearance, and pruritus severity were evaluated. A total of 71 patients with stage IB-IVA CTCL received intravenous denileukin diftitox 9 microg/kg/day or 18 microg/kg/day over 15-60 minutes for 5 consecutive days on an outpatient basis; cycles were planned for every 21 days for a total of 8 cycles over 6 months.

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The high-affinity human interleukin-7 (IL-7)R is a heterodimeric complex consisting of the IL-7Ralpha and common interleukin-2 receptor gamma (IL-2Rgamma(c)) chains. Activation of the IL-7R complex is associated with tyrosine and serine residue phosphorylation of a number of intracellular substrates leading to proliferation and induction of various cellular differentiation processes. In this study, we demonstrate, by S1 nuclease protection assay, immunoprecipitation and in vitro kinase assay that functional human (h) IL-7R is expressed in haematopoietic and nonhaematopoietic cell lines.

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Genetic engineering has led to the development of fusion protein toxins, which are targeted effector molecules that combine a targeting ligand such as a growth factor with a cytocidal moiety such as a plant or bacterial toxin. The first genetically constructed family of fusion proteins used diphtheria toxin as the toxophore for receptor-binding domain substitution. Diphtheria toxin consists of three domains: an enzymatically active adenosine diphosphate (ADP) ribosyltransferase domain, a hydrophobic transmembrane domain, and a C-terminal receptor-binding domain.

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Cutaneous T-cell lymphoma (CTCL) includes a heterogeneous group of diseases manifested in many cases by a prolonged clinical course. Even patients with advanced clinical disease, including erythroderma, adenopathy, and cutaneous tumors, can respond to a number of conservative therapeutic modalities, including radiation, cutaneous and extracorporeal phototherapy, and interferon. More aggressive systemic therapies are generally reserved for patients with visceral involvement or effaced (LN4) lymph node disease or patients refractory to multiple conservative approaches.

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DAB(389)IL-2 (denileukin diftitox, ONTAK) is a cytokine-targeted fusion protein that delivers the catalytic domain of diphtheria toxin to lymphoma cells expressing the interleukin-2 receptor (IL-2R). In phase I and phase III studies of DAB(389)IL-2 in patients with cutaneous T-cell lymphoma (CTCL), non-Hodgkin's lymphoma, and Hodgkin's disease in which premedications were limited to diphenhydramine and acetaminophen, acute infusion-related hypersensitivity reactions occurred in 70% of patients and vascular leak syndrome (VLS) in 27%, resulting in discontinuation of therapy in 29% of patients. There was no correlation between the dose or half-life of DAB(389)IL-2 and the occurrence of hypersensitivity events or VLS.

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Fusion proteins are recombinant molecules that combine a targeting mechanism to a cytocidal moiety. DAB(389)IL-2 (denileukin diftitox; ONTAK), with a unique mechanism of action, is the first genetically constructed fusion protein to reach the clinic. In this molecule, the interleukin-2 (IL-2) gene is genetically fused to the enzymatically active and translocating domains of diphtheria toxin.

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Recent phase I and phase II trials using recombinant human interleukin-12 (rhIL-12) for cutaneous T cell lymphoma (CTCL) have been completed. Observations on 32 evaluable patients revealed an overall response rate approaching 50 percent. Biopsy of regressing lesions revealed an increase in numbers of CD8+ and/or TIA-1+ T cells.

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The interleukin (IL)-2 receptor has proved an attractive target for T cell-directed therapies. Agents including monoclonal antibodies, single-chain antibody immunoconjugates, radioimmunoconjugates, and, most recently, ligand fusion toxins have demonstrated activity in vitro and in clinical trials in both hematologic malignancies and diseases characterized by proliferation of activated T cells, such as graft-versus-host disease. DAB389IL-2 (ONTAK) is a ligand fusion toxin consisting of the full-length sequence of the IL-2 gene genetically fused to the enzymatically active and translocating domains of diphtheria toxin.

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Purpose: To evaluate the role of 9-aminocamptothecin (9-AC), a synthetic camptothecin analog, in advanced cutaneous T-cell lymphoma (CTCL).

Methods: Eligible patients had stage IIB-IV CTCL. 9-AC was infused over 72 h at a dose of 1,100 microg/m2 per day (approximately 46 microg/m2/h) every 2 weeks, with granulocyte-colony stimulating factor (G-CSF) support.

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Extracorporeal photochemotherapy (ECP) has been associated with clinical improvement in several patients with acute and chronic graft-versus-host disease (cGVHD) after allogeneic bone marrow transplantation, but the mechanism of action is unknown. This study tested the hypothesis that in patients with cGVHD, ECP modulates alloreactivity by affecting activated lymphocyte populations or by altering the interaction between effector lymphocytes and antigen-presenting cells (APCs). Ten patients who had refractory cGVHD were treated with ECP, and the clinical response to and immunologic effects of this therapy were assessed.

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Proteases give cancer a defining characteristic of being able to break through extracellular matrix barriers and invade into other tissues in response to chemotactic signals. Recently, the cell surface protease-activated receptor (PAR)-1 has been shown to act as a chemokine receptor in inflammatory cells, and its expression is tightly correlated with metastatic propensity of breast cancer cells. The aim of the present study was to determine whether activation of PAR1 or the other known PARs (PAR2-4) can regulate migration and invasion of breast cancer cells.

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Purpose: The objective of this phase III study was to determine the efficacy, safety, and pharmacokinetics of denileukin diftitox (DAB389IL-2, Ontak [Ligand Pharmaceuticals Inc, San Diego, CA]) in patients with stage Ib to IVa cutaneous T-cell lymphoma (CTCL) who have previously received other therapeutic interventions.

Patients And Methods: Patients with biopsy-proven CTCL that expressed CD25 on > or = 20% of lymphocytes were assigned to one of two dose levels (9 or 18 microg/kg/d) of denileukin diftitox administered 5 consecutive days every 3 weeks for up to 8 cycles. Patients were monitored for toxicity and clinical efficacy, the latter assessed by changes in disease burden and quality of life measurements.

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Managing the infectious complications associated with pentostatin (Nipent), used alone or in combination with other agents in patients with low-grade lymphomas, poses a significant problem for clinicians. Since there is limited experience with these therapies, definitive treatment recommendations concerning prophylaxis cannot be made. The panel members discussed the use of valacyclovir (Valtrex) to provide prophylaxis for herpes zoster, trimethoprim/sulfamethoxazole for Pneumocystis, and acyclovir (Zovirax) for varicella zoster.

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Pentostatin (Nipent) has demonstrated significant activity as a single agent in patients with low-grade B- and T-cell lymphomas, but thus far, clinical experience with combinations of pentostatin and other agents is limited. A study of alternating administration of pentostatin and high-dose interferon-alfa-2a (Roferon A) in cutaneous T-cell lymphoma patients has been undertaken and has demonstrated a 41% response rate, with tolerable toxicity. Studies combining pentostatin with alkylating agents, including chlorambucil (Leukeran) and cyclophosphamide (Cytoxan, Neosar) in patients with chronic lymphocytic leukemia (CLL) have reported significant immunosuppression and have required dose modifications of one or both agents.

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Cutaneous T-cell lymphoma (CTCL) comprises a constellation of diseases of malignant clonal T lymphocytes that present initially in the skin. Since biochemical studies of pentostatin suggested that T cells are more sensitive to the effects of inhibition of adenosine deaminase by purine analogs, early studies with pentostatin were conducted in patients with refractory T-cell neoplasms. Durable responses were reported in several patients on phase I studies.

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In this preliminary study, we evaluated the effects of methylnaltrexone, a peripheral opioid-receptor antagonist, on chronic opioid-induced gut motility and transit changes in four subjects with chronic methadone-induced constipation. Subjects participated in this single blind, placebo controlled study for up to 8 days. We gave placebo the first day; for the remainder of the study, we gave intravenous methylnaltrexone (0.

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Background: This Phase II study was undertaken to assess the efficacy and toxicity of chemotherapy with etoposide, vincristine, doxorubicin, bolus cyclophosphamide, and oral prednisone (EPOCH regimen) in patients with advanced, refractory cutaneous T-cell lymphoma (CTCL).

Methods: Fifteen patients were treated with a 96-hour continuous infusion of etoposide, vincristine, doxorubicin, bolus cyclophosphamide, and oral prednisone, followed by granulocyte-colony stimulating factor support and trimethoprim/sulfamethoxazole prophylaxis. The median age of the patients was 53 years (range, 17-82 years).

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Endonucleolytic DNA fragmentation is the common end point and the prevailing indicator of apoptosis. We have identified a 70-kDa endonuclease (NUC70) that is activated in drug-induced apoptosis of human hematopoietic cells. We purified NUC70 to homogeneity and generated a rabbit polyclonal antibody to distinguish it from previously identified nucleases.

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Ten patients with advanced or refractory CD5-expressing hematologic neoplasms [two with chronic lymphocytic leukemia and eight with cutaneous T-cell lymphoma (CTCL)] were treated in a Phase I study with the radioimmunoconjugate 90Y-T101, which targets CD5+ lymphocytes. Prior imaging studies using 111In-T101 demonstrated uptake in involved lymph nodes and skin in patients with CTCL, and Phase I studies with unmodified T101 demonstrated transient responses. In this study, patients were treated with 5 or 10 mCi of 90Y chelated to T101 via isothiocyanatobenzyl diethylenetriamine pentaacetic acid, along with tracer doses of 111In-T101 for imaging.

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Cutaneous lymphomas comprise a spectrum of diseases characterized by infiltration of the skin by malignant lymphocytes. The clinical manifestations of cutaneous lymphomas vary, and they can mimic benign dermatoses, as well as nodal or visceral malignancies with cutaneous spread. Cutaneous lymphomas are divided into T-cell lymphomas and B-cell lymphomas.

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