Phase II-I-II study of two different doses and schedules of pralatrexate, a high-affinity substrate for the reduced folate carrier, in patients with relapsed or refractory lymphoma reveals marked activity in T-cell malignancies.

Purpose: To determine the maximum-tolerated dose (MTD) and efficacy of pralatrexate in patients with lymphoma.

Patients And Methods: Pralatrexate, initially given at a dose of 135 mg/m(2) on an every-other-week basis, was associated with stomatitis. A redesigned, weekly phase I/II study established an MTD of 30 mg/m(2) weekly for six weeks every 7 weeks.

Pralatrexate, a novel class of antifol with high affinity for the reduced folate carrier-type 1, produces marked complete and durable remissions in a diversity of chemotherapy refractory cases of T-cell lymphoma.

T-cell lymphomas (TCLs) are characterised by poor responses to therapy with brief durations of remissions. An early phase study of pralatrexate has demonstrated dramatic activity in patients with relapsed/refractory disease. Of the first 20 lymphoma patients treated, 16 had B-cell lymphoma and four had refractory aggressive TCL.

The schedule-dependent effects of the novel antifolate pralatrexate and gemcitabine are superior to methotrexate and cytarabine in models of human non-Hodgkin's lymphoma.

Purpose: Methotrexate is known to synergize with cytarabine [1-beta-D-arabinofuranosylcytosine (ara-C)] in a schedule-dependent manner. The purpose of this article is to compare and contrast the activity of pralatrexate (10-propargyl-10-deazaminopterin)/gemcitabine to the standard combination of methotrexate/ara-C and to determine if schedule dependency of this combination is important in lymphoma.

Experiment Design: Cytotoxicity assays using the standard trypan blue exclusion assay were used to explore the in vitro activity of pralatrexate and gemcitabine against a panel of lymphoma cell lines.

Pulsatile administration of the epidermal growth factor receptor inhibitor gefitinib is significantly more effective than continuous dosing for sensitizing tumors to paclitaxel.

Purpose: Gefitinib is an inhibitor of the epidermal growth factor receptor (EGFR) tyrosine kinase. Continuous inhibition of EGFR signaling is thought necessary for optimal inhibition of tumor cell proliferation. We hypothesized that continuous gefitinib may antagonize the effects of cytotoxics that inhibit tumor cells in other phases of the cell cycle.

Maitake beta-glucan MD-fraction enhances bone marrow colony formation and reduces doxorubicin toxicity in vitro.

Previous studies have indicated that MD-fraction (MDF), in which the active component is beta 1,6-glucan with beta 1,3-branches, has anti-tumor activity as an oral agent and acts as an immune adjuvant. Since some other beta glucans appear to promote mobilization of hematopoietic stem cells, the effects of a beta glucan extract from the Maitake mushroom "MD-fraction" on hematopoietic stem cells were examined in a colony forming assay. Here we report for the first time that MDF has a dose response effect on mouse bone marrow cells (BMC) hematopoiesis in vitro.