R. Mertelsmann

Lymphokine activated killer cells

SummaryVarious subpopulations of human leukocytes may be induced by lymphokines to exert cytotoxic activity. In man major histocompatibility complex non-restricted tumor cell lysis by interleukin-2 (IL-2) induced peripheral blood lymphocytes is attributed mainly to natural killer cells. These T cell receptor negative large granular lymphocytes are called lymphokine activated killer (LAK) cells. In order to explore the potential of LAK cells in tumor therapy, several clinical studies have been conducted, using IL-2 alone or in combination with ex vivo IL-2-activated peripheral blood lymphocytes. Objective responses have reproducibly been achieved only in renal cell carcinoma and malignant melanoma and were associated with considerable toxicity. In view of restricted efficacy and increasing doubts as to whether LAK cells indeed account for the in vivo observed responses, more recent strategies focus on tumor antigen specific cytotoxic T cells or tumor infiltrating lymphocytes. Successful translation of this approach into clinical practice, however, may be dependend on some basic problems of tumor immunology to be solved which were thought to be by-passed by the LAK cell approach.

Effect of granulocyte-macrophage colony-stimulating factor on neutropenia and related morbidity induced by myelotoxic chemotherapy

A phase Ib/II clinical study was undertaken to assess the efficacy of recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF) to attenuate neutropenia and associated morbidity caused by high-dose anticancer chemotherapy administered in the presence or absence of autologous bone marrow support. We treated 22 patients with various solid tumors and lymphoid neoplasias with a single daily subcutaneous dose of GM-CSF (250 micrograms/m2) 48 h after a second cycle of highly myelotoxic chemotherapy for a period of 10 days and compared intraindividually neutropenia-related clinical and laboratory variables with data obtained from the same patients having previously received a first neutropenia-inducing cycle of identical chemotherapy in the absence of GM-CSF. We show that GM-CSF is active in neutropenic patients by significantly increasing the neutrophil nadir, reducing the time of relevant neutropenia, and reducing the duration of the patients hospital stay and necessity for parenteral antibiotics. No significant toxicity was encountered with subcutaneous GM-CSF treatment.

A phase-II study of low-dose cyclophosphamide and recombinant human interleukin-2 in metastatic renal cell carcinoma and malignant melanoma

SummaryRecent preclinical and clinical studies that have demonstrated antitumor activity of high-dose recombinant interleukin-2 (rIL-2), and animal models that demonstrated a synergistic effect of low-dose cyclophosphamide, led us to study rIL-2 (Cetus Corp., Emeryville, Calif) in a phase II clinical trial in combination with low-dose cyclophosphamide in 32 patients, 18 with malignant melanoma and 14 with renal cell carcinoma. rIL-2 was given once daily at 3×106 U/m2, as a 30-min infusion for 14 days in cycle I and for 2×5 days in cycles II and III respectively; if tolerated, the dose was increased to a maximum of 6×106 U m−2 day−1; the cycles, separated by 1 week treatment-free intervals, were preceded each by a single i.v. bolus of cyclophosphamide at 350 mg/m2. The most prominent side-effects encountered in this trial consisted of a capillary leak syndrome, myalgia and fever that required dose reduction during the first cycle in one-half of the patients. Given the limit of tolerable toxicities in a standard care unit, the regimen employed achieved minor antitumor activity. No remission was achieved in patients with renal cell carcinoma, and 15% of melanoma patients showed objective responses (partial response + minor response).

Polypeptides controlling hematopoietic blood cell development and activation

SummaryColony-stimulating factors (CSFs) have entered the clinical arena. Several investigators have explored, in first clinical phase I studies, different routes of administration to define the optimum biological dose, maximum tolerated dose, toxicity, and pharmacokinetics of these reagents. It has been demonstrated that recombinant human (rh) granulocyte-macrophage CSF (GM-CSF) and granulocyte CSF (G-CSF) can be safely administered over a broad dose range to increase number of circulating granulocytes in man. More recently, GM-CSF and G-CSF have been involved in phase Ib/II studies to assess the granulopoietic responses of patients with granulocytopenia due to various underlying disease states including myelodysplastic syndrome, aplastic anemia, cyclic neutropenia, Kostmanns syndrome, and the acquired immuno-deficiency syndrome. Both factors were also investigated with respect to their potential to prevent chemotherapy induced granulocytopenia or to accelerate recovery from that condition. The short-term effects of rh GM-CSF after autologous bone marrow transplantation for various solid tumors and lymphoid malignancies were assessed as well. In this article we will focus on recent results that have emerged from in vivo studies utilizing CSFs.

A multicenter trial of interleukin-2 and low-dose cyclophosphamide in highly chemotherapy-resistant malignancies

The anti-tumor activity of high-dose recombinant interleukin-2 (IL-2) has been demonstrated in several recent preclinical and clinical studies. In an attempt to study possible synergistic effects with low-dose cyclophosphamide (CYC), a phase II clinical trial was initiated in 32 patients, 18 with malignant melanoma (MM) and 14 with renal cell carcinoma (RCC). The recombinant IL-2 (Cetus Corp., Emeryville, Ca, U.S.A.) was given once daily at 3 x 10(6) U/m2, as a 30-min infusion for 14 days in cycle I and for five days twice in cycles II and III, respectively; if tolerated, the dose was escalated to a maximum of 6 x 10(6) U/m2/day; the cycles, separated by 1-week treatment-free intervals, were each preceded by a single i.v. bolus of CYC at 350 mg/m2. The most prominent side-effects encountered in this trial consisted of a capillary leak syndrome, myalgia and fever requiring dose reduction in half of the patients during the first cycle. Given the limit of tolerable toxicities in a standard care unit, the regimen employed achieved minor anti-tumor activity. No objective responses were achieved in patients with RCC and a 15% remission rate (PR + MR) was seen in melanoma patients.

Effect of Treatment with rhGM-CSF and Low-Dose Cytosine Arabinoside on Leukemic Blast Cells in Patients with Myelodysplastic Syndromes

Treatment of patients having myelodysplastic a syndromes (MDS) with approaches such as differentiation induction, single cytostatic agents or supportive care only has, up to now, been rather unsuccessful. Aggressive chemotherapy followed by bone marrow transplantation is only suitable for a very small proportion of patients. Thus, there is a need for new therapeutic alternatives.

MACOP-B chemotherapy for the treatment of high grade and intermediate grade Non Hodgkin's lymphoma

SummaryBetween Nov. 1985 and Nov. 1988, sixty-three patients with high grade malignant (hg) and intermediate grade malignant (img) Non Hodgkins Lymphoma (NHL) were treated with MACOP-B (methotrexate, doborubicin, cyclophosphamide, vincristine, prednison and bleomycin). Thirty-seven patients received MACOP-B as an upfront treatment modality, whereas twenty-six patients had relapsed disease and received MACOP-B as a salvage protocol. Four weeks after termination of therapy, 75% of patients with de novo NHL and 72% of the patients with relapsed NHL were in complete remission (CR). In the group of newly diagnosed NHL, 22% achieved partial remission (PR) and 3% no change (NC), whereas in the group with relapsed disease 14% had PR and 14% had progressive disease (PD). At a medium follow-up of 12 months (range 1 month to 33 months), 74% of patients with de novo NHL continued to be in CR whereas the continuous CR rate in patients with relapsed disease was 35%. Overall survival after 30 months of observation for the patient group with de novo NHL was 75% and 40% for patients with relapsed NHL. The mean duration for completion of the projected 12 chemotherapy cycles, given in weekly intervals, was 12.9 and 13.5 weeks in upfront or salvage therapy, respectively. With low incidence of major toxicities, application of drugs on an outpatient basis, and high efficacy, MACOP-B shows substantial advantges for therapy of de novo and relapsed NHL.

Monocyte Interleukin-1 Secretion Is Regulated by the Sequential Action of γ-Interferon and Interleukin-2 Involving Monocyte Surface Expression of Interleukin-2 Receptors

Interleukin-1 (IL-1) is a polypeptide synthesized as a high-mol.-wt. precursor and subsequently secreted after proteolytic cleavage to 17500-dalton active forms in murine [1] and human cells [2]. Recently, cDNAs for murine [3] and for two distinct human IL-1 species, IL-1α and IL- 1β, have been isolated, sequenced, and cloned [2, 4].

Effect of Granulocyte-Macrophage Colony-Stimulating Factor on Neutropenia and Related Morbidity Induced by Myelotoxic Chemotherapy

PURPOSE A phase Ib/II clinical study was undertaken to assess the efficacy of recombinant human (rh) granulocyte-macrophage colony-stimulating (GM-CSF) factor in attenuating neutropenia and associated morbidity caused by high-dose anticancer chemotherapy administered in the presence or absence of autologous bone marrow support. PATIENTS AND METHODS Twenty-two patients with various solid tumors and lymphoid neoplasias were treated with a single daily subcutaneous dose of rh GM-CSF (250 micrograms/m2) 48 hours after receiving a second cycle of highly myelotoxic chemotherapy for a period of 10 days. Within-subject comparisons on neutropenia-related clinical and laboratory variables were made with data obtained from the same patients after they received the first neutropenia-inducing cycle of identical chemotherapy in the absence of GM-CSF. RESULTS GM-CSF was active in neutropenic patients because it significantly increased the neutrophilic nadir, reduced the time of relevant neutropenia, and reduced the duration of a patients hospital stay and the necessity for parenteral antibiotics. No significant toxicity was encountered with subcutaneous GM-CSF treatment. CONCLUSION Although GM-CSF was shown to significantly reduce chemotherapy-associated morbidity in patients receiving myelotoxic cancer chemotherapy, additional studies are needed to assess whether the use of GM-CSF in anticancer chemotherapy will allow an increase in the dosage level, leading to improved response rates and survival among cancer patients.

Gamma-Interferon Regulates Secretion of G-CSF in Human Monocytes on the Transcriptional Level

The production of colony stimulating factors (CSF) for granulocytes and monocytes is integrated into a network of communicating soluble messenger molecules resulting from T-cell/monocyte interactions. We assessed the capactiy of gamma-Interferon to modulate monocyte secretion of CSF by colony assays and Northern blot analysis to hybridize monocyte RNA with cDNA probes of different CSF-types. Whereas mRNA for GM-CSF was undetectable in untreated and gamma-IFN treated peripheral blood monocytes, the constitutive expression of mRNA for G-CSF and subsequent production of a CSF with biological activities similar to G-CSF could highly be enhanced by exposure of monocytes to gamma-IFN.