0000000000289193
AUTHOR
Anthony D. Ho
The role of recent thymic emigrant-regulatory T-cell (RTE-Treg) differentiation during pregnancy.
During pregnancy, regulatory T cells (Tregs) have a key role in maternal immune tolerance to the semi-allogeneic fetus. Our previous results showed that the naive CD45RA(+)-Treg pool is functionally improved in pregnant women compared with non-pregnant women. Therefore, we examined the thymic output and differentiation of CD45RA(+)CD31(+) recent thymic emigrant (RTE)-Tregs during normal pregnancy and in the presence of preeclampsia. With the onset of pregnancy, the composition of the total CD4(+)CD127(low+/-)FoxP3(+)-Treg pool changed in the way that its percentage of RTE- and CD45RA(-)CD31(+)-memory Tregs decreased strongly, whereas that of the CD45RA(+)CD31(-)-mature naive (MN)-Tregs did …
Imatinib combined with mitoxantrone/etoposide and cytarabine is an effective induction therapy for patients with chronic myeloid leukemia in myeloid blast crisis.
BACKGROUND Despite advances in drug therapy and allogeneic stem cell transplantation (allo-SCT), the prognosis of patients with chronic myeloid leukemia (CML) in blast crisis remains poor. Imatinib has demonstrated synergistic effects in vitro with mitoxantrone, etoposide, and cytarabine. METHODS A Phase I/II trial was performed in patients with CML myeloid blast crisis. Patients were treated with imatinib + mitoxantrone/etoposide in four cohorts: mitoxantrone 10 mg/m2/day and etoposide 100 mg/m2/day for 2 or 3 consecutive days and imatinib 600 mg/day from Day 15 (cohorts 1 and 2) or from Day 1 (cohorts 3 and 4). After hematologic reconstitution after the cytopenic phase, cytarabine was giv…
Safety and Clinical Activity of Temsirolimus in Combination with Rituximab and DHAP in Patients with Relapsed or Refractory Diffuse Large B-Cell Lymphoma - Results of the Part I Cohort of the STORM Trial
Abstract Purpose. To evaluate the safety, tolerability and efficacy of the combination of the mTOR inhibitor Temsirolimus and a standard salvage regimen (R-DHAP) in patients with relapsed or refractory diffuse large cell B-Cell lymphoma (DLBCL). Patients and Methods. This is a prospective, multicenter, phase II, open-label study. Patients with relapsed or refractory DLBCL with a maximum of two prior treatment lines were eligible. The STORM regimen consisted of Rituximab 375 mg/m² (day 2) and DHAP (Dexamethasone 40mg day 3-6, Cisplatine 100 mg/m² day 3, Cytarabine 2x2 g/m² day 4) with Temsirolimus added on day 1 and 8 of a 21 d cycle, with 2-4 cycles planned. In part I, dose levels for the m…
Evaluation of Stem Cell Mobilization in Patients with Multiple Myeloma after Lenalidomide-Based Induction Chemotherapy within the GMMG-HD6 Trial
Abstract Introduction: The German-Speaking Myeloma Multicenter Group (GMMG) has initiated a randomized multicenter phase III trial on the effect of elotuzumab in VRD (bortezomib, lenalidomide, dexamethasone) induction/consolidation and lenalidomide maintenance in patients with newly diagnosed multiple myeloma (GMMG-HD6 trial, NCT02495922). The study compares four cycles induction therapy with VRD vs. VRD + elotuzumab, followed by standard intensification (i.e. mobilization and stem cell transplantation), two cycles consolidation with VRD/VRD + elotuzumab and lenalidomide maintenance +/- elotuzumab. The primary endpoint is determination of the best of four treatment strategies regarding prog…
The mTOR Inhibitor Temsirolimus Added to Rituximab Combined With Dexamethasone, Cytarabine, and Cisplatinum (R-DHAP) for the Treatment of Patients With Relapsed or Refractory DLBCL – Results From the Phase-II STORM Trial
There is a high need for novel treatment options in relapsed and refractory diffuse large B-cell lymphoma. Single agent mammalian target of rapamycin (mTOR) inhibitor treatment has shown promising efficacy in this entity. Here, we report on the results of the mTOR-inhibitor temsirolimus combined to standard rituximab-DHAP salvage regimen in a prospective, multicenter, phase II, open-label study. The STORM regimen consisted of rituximab 375 mg/m(2) (day 2) and DHAP (dexamethasone 40 mg day 3-6, cisplatinum 100 mg/m(2) day 3, cytarabine 2 × 2 g/m(2) day 4) with temsirolimus added on day 1 and 8 of a 21-day cycle, with 2 to 4 cycles planned. In part I, dose levels of 25, 50, 75, and 100 mg fo…
Safety and Clinical Activity of Temsirolimus in Combination with Rituximab and DHAP in Patients with Relapsed or Refractory Diffuse Large B-Cell Lymphoma - Report of the Prospective, Multicenter Phase II STORM Trial
Abstract Purpose. To evaluate the safety, tolerability and efficacy of the combination of the mTOR inhibitor Temsirolimus and a standard salvage regimen (R-DHAP) in patients with relapsed or refractory diffuse large cell B-Cell lymphoma (DLBCL). Methods. This is a prospective, multicenter, phase II, open-label study. Patients with relapsed or refractory DLBCL with a maximum of two prior treatment lines were eligible. The STORM regimen consisted of Rituximab 375 mg/m² (day 2) and DHAP (Dexamethasone 40mg day 3-6, Cisplatine 100 mg/m² day 3, Cytarabine 2x2 g/m² day 4) with Temsirolimus added on day 1 and 8 of a 21 d cycle, with 2-4 cycles planned. In part I, dose levels of 25, 50, 75 and 100 …
Cytotoxicity of tumor antigen specific human T cells is unimpaired by arginine depletion.
Tumor-growth is often associated with the expansion of myeloid derived suppressor cells that lead to local or systemic arginine depletion via the enzyme arginase. It is generally assumed that this arginine deficiency induces a global shut-down of T cell activation with ensuing tumor immune escape. While the impact of arginine depletion on polyclonal T cell proliferation and cytokine secretion is well documented, its influence on chemotaxis, cytotoxicity and antigen specific activation of human T cells has not been demonstrated so far. We show here that chemotaxis and early calcium signaling of human T cells are unimpaired in the absence of arginine. We then analyzed CD8(+) T cell activation…
Arginine deficiency leads to impaired cofilin dephosphorylation in activated human T lymphocytes
The amino acid arginine is fundamentally involved in the regulation of the immune response during infection, inflammatory diseases and tumor growth. Arginine deficiency (e.g. due to the myeloid cell enzyme arginase) inhibits proliferation and effector functions of activated T lymphocytes. Here, we studied intracellular mechanisms mediating this suppression of human T lymphocytes. Our proteomic analysis revealed an impaired dephosphorylation of the actin-binding protein cofilin upon T-cell activation in the absence of arginine. We show that this correlates with alteration of actin polymerization and impaired accumulation of CD2 and CD3 in the evolving immunological synapse in T cell-antigen …
Combination Treatment with Imatinib and Mitoxantrone/Etoposide Is a Suitable Preparative Regimen before Allogeneic Transplantation in Patients with Myeloid Blast Crisis of Chronic Myeloid Leukemia.
Abstract In advanced BCR-ABL-positive leukemia, combination of chemotherapy with imatinib is expected to result in better reduction of leukemia cell load and may delay or offset clonal selection of resistant leukemia cells, thus improving the survival. We carried out a prospective phase I/II combination trial for patients (pts) with myeloid blast crisis of chronic myelogenous leukemia (CML). Pts were treated with imatinib+mitoxantrone/etoposide in four cohorts starting from mitoxantrone 10mg/m2/d and etoposide 100 mg/m2/d for 2 or 3 consecutive days and start of imatinib 600mg/d from day 15 (coh. 1 and 2) or from day 1 (coh. 3 and 4, respectively). After hematologic reconstitution following…
Distinct Activities of Glycolytic Enzymes Identify Chronic Lymphocytic Leukemia Patients with a more Aggressive Course and Resistance to Chemo-Immunotherapy.
A higher capacity to grow under hypoxic conditions can lead to a more aggressive behavior of tumor cells. Determining tumor activity under hypoxia may identify chronic lymphocytic leukemia (CLL) with aggressive clinical course and predict response to chemo-immunotherapy (CIT). A metabolic score was generated by determining pyruvate kinase and lactate dehydrogenase, key enzymes of glycolysis, ex vivo in primary CLL samples under normoxic and hypoxic conditions. This score was further correlated with clinical endpoints and response to CIT in 96 CLL patients. 45 patients were classified as metabolic high risk (HR), 51 as low risk (LR). Treatment-free survival (TFS) was significantly shorter in…