Growth factors and cytokines upregulate gelatinase expression in bone marrow CD34(+) cells and their transmigration through reconstituted basement membrane.
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The mechanism(s) underlying the release of stem/progenitor cells from bone marrow into the circulation is poorly understood. We hypothesized that matrix metalloproteinases (MMPs), especially gelatinases, which are believed to participate in the proteolysis of basement membranes and in the migration of leukocytes, may facilitate this process. First, we investigated whether CD34(+) stem/progenitor cells express gelatinases A (MMP-2) and/or B (MMP-9) and whether growth factors and cytokines (granulocyte colony-stimulating factor [G-CSF], granulocyte-macrophage colony-stimulating factor [GM-CSF], stem cell factor [SCF], macrophage colony-stimulating factor [M-CSF], interleukin-3 [IL-3], IL-6, IL-8, and tumor necrosis factor-alpha [TNF-alpha]) are able to modulate their expression. Next, we examined the transmigration of these stem/progenitor cells through reconstituted basement membrane (Matrigel) and its modulation by growth factors and cytokines. CD34(+) cells were obtained from steady-state bone marrow and peripheral blood (from leukapheresis products collected either in steady-state hematopoiesis or after mobilization with G-CSF plus chemotherapy or G-CSF alone). We found that peripheral blood CD34(+) cells, regardless of whether they were mobilized or not, strongly expressed both gelatinases (MMP-2 and MMP-9) in contrast to steady-state bone marrow CD34(+) cells, which did not. However, all the growth factors and cytokines tested could induce MMP-2 and MMP-9 secretion by the latter cells. Moreover, the stimulatory effects of G-CSF and SCF on both MMP-2 and MMP-9 secretion were found to be significantly higher in CD34(+) cells isolated from bone marrow than in those from peripheral blood. In addition TNF-alpha, GM-CSF, and IL-6 increased the secretion of a partially active form of MMP-2. Basal transmigration of bone marrow CD34(+) cells through Matrigel was lower than that of peripheral blood CD34(+) cells (P <.0001), but growth factors and cytokines increased it by 50% to 150%. Positive correlations were established between expression of gelatinases and CD34(+) cell migration (r >.9). The stimulatory effect of G-CSF was significantly greater on the migration of CD34(+) cells from bone marrow than on those from peripheral blood (P =.004). Moreover, CD34(+) cell migration was reduced to approximately 50% by antibodies to MMP-2 and MMP-9, tissue inhibitors of metalloproteinases (rhTIMP-1 and -2), and o-phenanthroline. TNF-alpha-induced gelatinase secretion and migration of CD34(+) cells and of clonogenic progenitors (colony-forming unit-granulocyte-macrophage [CFU-GM], burst-forming unit-erythroid [BFU-E], colony-forming unit granulocyte, erythroid, monocyte, megakaryocyte [CFU-GEMM], and colony-forming unit-megakaryocyte [CFU-MK]) were dose-dependent. Therefore, this study demonstrated that CD34(+) cells that are circulating in peripheral blood express both MMP-2 and MMP-9 and transmigrate through Matrigel. In contrast, CD34(+) cells from steady-state bone marrow acquire similar properties after exposure to growth factors and cytokines, which upregulate expression of gelatinases and transmigration of these cells when they enter the bloodstream. Hence, we suggest that growth factors and cytokines induce release of stem/progenitor cells from bone marrow into peripheral blood during mobilization, as well as during steady-state hematopoiesis, by signaling through gelatinase pathways. (+info)
Additive effects of human recombinant interleukin-11 and granulocyte colony-stimulating factor in experimental gram-negative sepsis.
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Recombinant human granulocyte colony-stimulating factor (rhG-CSF) is widely used to promote granulocyte recovery from a variety of pathologic states. Recombinant human interleukin-11 (rhIL-11) has recently become available clinically as a platelet restorative agent after myelosuppressive chemotherapy. Preclinical data has shown that rhIL-11 limits mucosal injury after chemotherapy and attenuates the proinflammatory cytokine response. The potential efficacy of combination therapy with recombinant human forms of rhIL-11 and rhG-CSF was studied in a neutropenic rat model of Pseudomonas aeruginosa sepsis. At the onset of neutropenia, animals were randomly assigned to receive either rhG-CSF at a dose of 200 micrograms/kg subcutaneously every 24 hours for 7 days; rhIL-11 at 200 micrograms/kg subcutaneously every 24 hours for 7 days; the combination of both rhG-CSF and rhIL-11; or saline control. Animals were orally colonized with Pseudomonas aeruginosa 12.4.4 and then given a myelosuppressive dose of cyclophosphamide. rhG-CSF resulted in a slight increase in absolute neutrophil counts (ANC), but did not provide a survival advantage (0 of 12, 0% survival) compared with the placebo group (1 of 12, 8% survival). rhIL-11 was partially protective (4 of 10, 40% survival); the combination of rhG-CSF and rhIL-11 resulted in a survival rate of 80% (16 of 20; P <.001). rhIL-11 alone or in combination with rhG-CSF resulted in preservation of gastrointestinal mucosal integrity (P <.001), lower circulating endotoxin levels (P <.01), and reduced quantitative levels of P. aeruginosa in quantitative organ cultures. These results indicate that the combination of rhIL-11 and rhG-CSF is additive as a treatment strategy in the prevention and treatment of experimental Gram-negative sepsis in immunocompromised animals. This combination may prove to be efficacious in the prevention of severe sepsis in neutropenic patients. (+info)
Infusional paclitaxel and weekly vinorelbine chemotherapy with concurrent filgrastim for metastatic breast cancer: high complete response rate in a phase I-II study of doxorubicin-treated patients.
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PURPOSE: We investigated 96-hour paclitaxel infusion combined with weekly (days eight and 15) vinorelbine as salvage therapy for metastatic breast cancer in anthracycline-exposed patients. All patients received scheduled support with granulocyte colony-stimulating factor (G-CSF; filgrastim). Tumor response, toxicity, time to progression (TTP), and survival were assessed. PATIENTS AND METHODS: This single-center nonrandomized trial enrolled 32 patients. Anthracycline exposure and subsequent progression were common to all patients. Paclitaxel and vinorelbine were escalated over three dosing levels, stratified by liver function. RESULTS: Seven patients (22%) achieved a complete response and nine patients achieved a partial response for an overall response rate of 50%. The median TTP was 6.1 months, and median survival time was 14.1 months. Dose-limiting toxicity was neutropenia, with dose delay or reduction in seven of 32 patients. Febrile neutropenia requiring hospitalization was uncommon (three of 32 patients; 9%). There were no treatment-related deaths. Grade 3/4 thrombocytopenia occurred in two patients (6%), and 13 patients (41%) required RBC transfusions for anemia. Grade 3 nausea and vomiting was seen in one patient, who was found to be Addisonian. Despite potentially overlapping neurologic toxicities of the two agents, only two patients (6%) were removed from the study because of progressive peripheral neuropathy. CONCLUSION: Administration of 96-hour paclitaxel infusion and subsequent weekly vinorelbine with G-CSF support is well tolerated. The response rate, TTP, and survival data are encouraging for therapy given to anthracycline pretreated patients with metastatic breast cancer. If these results can be verified in multi-institution trials, this or a similar combination of drugs would merit investigation as first-line therapy in this patient population. (+info)
Phase II trial of high-dose liposome-encapsulated doxorubicin with granulocyte colony-stimulating factor in metastatic breast cancer. TLC D-99 Study Group.
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PURPOSE: To estimate the toxicity and response rate of high-dose liposome-encapsulated doxorubicin (TLC D-99, Evacet, The Liposome Company Inc, Princeton, NJ) in patients with advanced breast cancer. PATIENTS AND METHODS: Fifty-two breast cancer patients with bidimensionally measurable metastatic disease and no prior chemotherapy for metastatic disease received a 135 mg/m2 intravenous (i.v.) bolus of TLC D-99 with 5 microg/kg of granulocyte colony-stimulating factor via subcutaneous injection every 21 days. RESULTS: The median number of treatment cycles of TLC D-99 was three (range, one to 10 cycles), and the median total cumulative dose of TLC D-99 was 405 mg/m2 (range, 135 to 1,065 mg/m2). Grade IV neutropenia, thrombocytopenia, and mucositis were experienced by 48 (92%), 46 (88%), and 10 (19%) patients, respectively. Twenty (38%) of patients experienced cardiac toxicity: four (8%) experienced a decrease of 20% or more in left ventricular ejection fraction (LVEF) to a final value > or = 50%, nine (17%) experienced a decrease of 10% or more in LVEF to a final value less than 50%, and seven (13%) developed symptomatic congestive heart failure (CHF), including one patient who died of cardiomyopathy after receiving a total dose of 1,035 mg/m2. In a stepwise logistic regression model, the significant risk factors for the development of CHF were the cumulative dose of prior adjuvant doxorubicin (P = .007) and the total cumulative dose of TLC D-99 (P = .032). The overall response rate was 46% (95% confidence interval [CI], 32% to 61%) on an intent-to-treat basis. The median duration of response was 7.4 months (95% CI, 6.1 to 19.6 months) and the median progression-free survival was 6.1 months (95% CI, 5.4 to 7.5 months). CONCLUSION: There was no added therapeutic benefit to the dose escalation of TLC D-99 in this study. A high rate of cardiotoxicity was also observed, especially among patients who had received prior adjuvant doxorubicin. This was probably attributable to the dose and schedule of TLC D-99 used in this trial, as well as the patient's lifetime cumulative doxorubicin dose. Administration of high-dose TLC D-99 at 135 mg/m2 every 3 weeks by i.v. bolus infusion does not warrant further investigation. (+info)
Introduction: current issues in high-dose chemotherapy and stem cell support.
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In the 1980s it became clear that low numbers of primitive hematopoietic cells were present in the peripheral bloodstream. Early clinical trials by investigators in the USA, Australia, and Germany demonstrated that these cells could be collected and reinfused to support high-dose chemotherapy procedures in patients otherwise unable to undergo bone marrow collection, usually because of prior pelvic irradiation. It was, however, difficult to obtain adequate numbers of stem cells from patients in the steady state. It was not until the demonstration by Socinski in Boston and Gianni in Milan that these circulating cells were markedly increased following the administration of either cytokines, chemotherapy, or a combination of both that the use of peripheral blood stem cells over bone marrow began to be widely undertaken. Since that time, peripheral blood stem cell collection has become the preferred means of stem cell support for high-dose chemotherapy because of the reduction in time to neutrophil and platelet engraftment, reduction in the number of transfusions and hospital stay, and an apparent reduction in tumor cell contamination. (+info)
The utilization of cytokines in stem cell mobilization strategies.
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High-dose myeloablative chemotherapy supported by peripheral blood progenitor cell (PBPC) transplant is rapidly replacing bone marrow transplant to treat a number of chemosensitive cancers. Numerous investigators have studied the relationship of CD34+ cell dose and engraftment kinetics in an effort to help define minimum and optimum target stem cell doses. A number of studies suggest that reinfusion of > or = 5 x 10(6) CD34+ PBPCs results in prompt and durable platelet engraftment. Mobilization of stem cells can be accomplished through use of chemotherapy alone, colony-stimulating factors, or a combination of the two. Strategies to improve PBPC yields include filgrastim in combination with chemotherapy or with other hematopoietic growth factors. In this paper, the advantages and disadvantages of these strategies will be discussed, and the results of a recently conducted, randomized, controlled phase 3 clinical trial in breast cancer patients receiving either SCF plus filgrastim or filgrastim alone for PBPC mobilization will be reviewed. (+info)
Management strategies for the hard-to-mobilize patient.
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Delayed hematopoietic engraftment, particularly of platelets, is seen in 5-35% of patients undergoing high-dose chemotherapy with autologous stem cell transplantation. Studies indicate that delayed engraftment is related to low CD34+ cell dose, and that risk factors for poor mobilization of CD34+ cells relate primarily to the type and extent of prior therapy. Data indicating an appropriate strategy to ensure that 'hard-to-mobilize' patients will achieve adequate CD34+ cell numbers are limited. It is clear, however, that marrow harvesting (performed frequently by a number of centers), is of limited value. Remobilization, best accomplished with a regimen of high-dose chemotherapy and cytokines, is of benefit in selected patients, but has substantial costs and morbidity. Instead of ad hoc treatment of patients who have a poor first mobilization, high-risk groups should be identified prospectively, and strategies should be developed to ensure adequate mobilization in all high-risk patients. The first randomized trial utilizing this approach has recently been reported. In this trial, stem cell mobilization with granulocyte colony-stimulating factor (G-CSF) alone was compared to mobilization with G-CSF combined with stem cell factor (SCF) in heavily pretreated patients with Hodgkin's and non-Hodgkin's lymphoma. The combination of G-CSF and SCF led to collection of a higher total CD34+ cell dose compared to G-CSF alone. Further, more patients in the combination group were able to mobilize an optimal CD34+ cell dose (ie 5 x 10(6)/kg). Additional trials are needed to determine long-term outcomes and the economic impact of achieving optimal stem cell mobilization in these patients, who would otherwise not be candidates for high-dose chemotherapy. (+info)
The role of STAT3 in granulocyte colony-stimulating factor-induced enhancement of neutrophilic differentiation of Me2SO-treated HL-60 cells. GM-CSF inhibits the nuclear translocation of tyrosine-phosphorylated STAT3.
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The role of granulocyte colony-stimulating factor (G-CSF) on neutrophilic differentiation of Me2SO-treated HL-60 cells was studied. G-CSF augmented the functional maturation of Me2SO-treated HL-60 cells in terms of both O-2-generating ability and expression of the formyl-methionyl-leucyl-phenylalanine receptor. G-CSF induced enhancement of cell growth in Me2SO-treated HL-60 cells. These results indicate that G-CSF is a potent enhancer for the differentiation and proliferation of Me2SO-treated HL-60 cells. G-CSF caused the activation of p70 S6 kinase but not mitogen-activated protein (MAP) kinase. On the other hand, G-CSF rapidly induced tyrosine phosphorylation of signal transducers and activators of transcription-3 (STAT3), but did not induce serine727 phosphorylation. From the analysis of confocal laser scanning fluorescence microscopy and differential centrifugation, it was clearly demonstrated that G-CSF induced nuclear translocation of tyrosine-phosphorylated STAT3. The G-CSF-dependent enhancement of neutrophilic differentiation in Me2SO-HL-60 cells was reversely inhibited by granulocyte-macrophage colony-stimulating factor (GM-CSF). Notably, in the presence of GM-CSF, G-CSF induced the tyrosine phosphorylation of STAT3 but failed to induce the nuclear translocation of tyrosine-phosphorylated STAT3. GM-CSF induced activation of not only p70 S6 kinase, but also of MAP kinase. Furthermore, GM-CSF caused the rapid serine727 phosphorylation of STAT3, both in the presence and absence of G-CSF. PD98059, an MEK1 inhibitor, inhibited the G-CSF-dependent serine727 phosphorylation of STAT3 and blocked the inhibitory effect of GM-CSF on G-CSF-dependent nuclear translocation of STAT3. These results suggest that G-CSF-dependent nuclear translocation of STAT3 coordinates with the promotion of neutrophilic differentiation in Me2SO-treated HL-60 cells. (+info)