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J Otten,
L Schmitz,
E Vettorazzi,
A Schultze,
A H Marx,
R Simon,
J Krauter,
S Loges,
G Sauter,
C Bokemeyer, W Fiedler
Leukemia: official journal of the Leukemia Society of America, Leukemia Research Fund, U.K 02/2011; 25(2):375-9. · 8.30 Impact Factor
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ABSTRACT: this phase I, open-label, dose-escalation study investigated SU14813, an oral multitargeted tyrosine kinase inhibitor, in adults with solid tumors.
seventy-seven patients received once-daily SU14813, either for 4 weeks followed by 1 week off treatment (schedule 4/1) or continuously [continuous daily dosing (CDD)]. The primary end point was to determine the maximum tolerated dose (MTD). Safety, pharmacokinetics, pharmacodynamics, and efficacy were assessed.
MTDs were 200 mg/day on schedule 4/1 and 100 mg/day with CDD. Adverse events included fatigue (64%), diarrhea (61%), nausea (44%), anorexia (43%), and vomiting (42%). SU14813 steady state was attained by day 8. Exposure increased in a generally dose-proportional manner and SU14813 was eliminated with a mean terminal half-life of 9-34 h. Target plasma concentrations (>100 ng/ml SU14813) were achieved and sustained over 12 h at ≥ 100 mg/day. Progression-free survival among the 1 complete responder and 12 partial responders was 1.4-53.2 months. Fifteen patients remained on treatment at 1 year and 3 patients at 2 years.
SU14813 has manageable safety and tolerability and allows once-daily continuous oral dosing. SU14813 shows dose-proportional pharmacokinetics, with target plasma concentrations achieved at doses ≥ 100 mg/day. Clinically meaningful activity with durable responses was observed, meriting further study.
Annals of Oncology 01/2011; 22(1):195-201. · 6.43 Impact Factor
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ABSTRACT: Up to 10% of germ cell tumor patients require salvage high-dose chemotherapy with stem cell support, achieving cure rates in the range of 10-60%. Stem cell mobilization may be difficult in these patients because of multiple lines of treatment known to seriously hamper stem cell recovery. Plerixafor significantly enhances the success of the CD34+ cell harvest, even in cases where prior mobilization attempts have failed. Six germ cell tumor patients provided informed consent and were included in the compassionate use program. All patients were heavily pretreated, with a median of 3.5 prior lines of therapy. All failed prior mobilization with G-CSF in combination with chemotherapy. Five patients yielded a median of 2.6 × 10(6) CD34+ cells per kg body weight in a median of 4 apheresis days when plerixafor was used. Three patients underwent subsequent high-dose chemotherapy with autologous stem cell support. Median time to leukocyte engraftment was 11 days. Median time to platelet engraftment was 12.5 days, both of which are comparable to previous historical data. Accordingly, plerixafor seems to be safe and effective in germ cell tumor patients who have failed prior mobilization therapy. Larger prospective studies are warranted to further assess its use in germ cell cancer.
Bone marrow transplantation 11/2010; 46(8):1053-6. · 3.00 Impact Factor
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ABSTRACT: Acute myeloid leukemia (AML) is a malignant disease characterized by deregulated proliferation of immature myeloid cells. Constitutive activation of the phosphatidylinositol 3-kinase (PI3K)/AKT signaling pathway is frequently detected in approximately 50-70% of AML patients. The gene INPP5D encodes the SH2-containing inositol 5-phosphatase 1 (SHIP1), which is a negative regulator of PI3K/AKT signaling. After lentiviral-mediated gene transfer of INPP5D into CD34(+) cells derived from AML patients (n=12) the granulocyte macrophage-colony stimulating factor (GM-CSF)-dependent proliferation was reduced in all samples analyzed (average 86%; range 72-93%). An enzymatically inactive form of SHIP1 (D672A) had no effect. In addition, SHIP1 reduced the autonomous proliferation of CD34(+) cells from a patient with a secondary AML who had a very high peripheral blast count (300 x 10(9) l(-1)). These data show that SHIP1 can effectively block GM-CSF-dependent and autonomous proliferation of AML cells.
Gene therapy 02/2009; 16(4):570-3. · 4.75 Impact Factor
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ABSTRACT: Functional and morphological properties of tumor microcirculation play a pivotal role in tumor progression, metastasis and inefficiency of tumor therapies. Despite enormous insights into tumor angiogenesis in solid tumors, little is known about the time-course-dependent properties of tumor vascularization in hematologic malignancies. The aim of this study was to establish a model of myeloid leukemia, which allows long-term monitoring of tumor progression and associated microcirculation. Red fluorescent protein-transduced human leukemic cell lines (M-07e) were implanted into cranial windows of severe combined immunodeficient mice. Intravital microscopy was performed over 55 days to measure functional (microvascular permeability, tissue perfusion rate and leukocyte-endothelium interactions) and morphological vascular parameters (vessel density, distribution and diameter). Tumor progression was associated with elevated microvascular permeability and an initial angiogenic wave followed by decreased vessel density combined with reduced tissue perfusion due to loss in small vessels and development of heterogenous tumor vascularization. Following altered geometric resistance of microcirculation, leukocyte-endothelium interactions were more frequent without increased leukocyte extravasation. It was concluded that time-dependent alterations of leukemic tumor vascularization exhibit strong similarities to those found in solid tumors. The potential contribution to the development of barriers to drug delivery in leukemic tumors is discussed.
Leukemia: official journal of the Leukemia Society of America, Leukemia Research Fund, U.K 02/2008; 22(1):59-65. · 8.30 Impact Factor
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ABSTRACT: Esophageal squamous cell carcinoma (ESCC) is the most common histological subtype of cancer in the upper and middle esophagus and is characterized by a high rate of mortality. The incidence of esophageal cancer varies greatly among regions of the world and occurs at a high frequency in Asia and South America.
In our department, a 51-year-old man was diagnosed with ESCC after presenting with extensive disseminated skin nodules. Biopsy of the nodules showed metastatic ESCC. Cutaneous manifestations of esophageal neoplasia are very rare and are mainly described for esophageal adenocarcinoma (EADC). Here we report a very uncommon case of extensive skin metastases of ESCC.
Early biopsies of suspicious skin lesions are important and should be performed in patients with unclear symptoms such as weight loss or dysphagia and especially in patients with a history of cancer, since they can reveal the existence of a distant malignant disease leading to diagnosis and prompt therapy.
Journal of Medical Case Reports 02/2008; 2:115.
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Der Urologe 10/2007; 46(9):1289-90. · 0.50 Impact Factor
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Der Urologe 08/2007; 46(9):1289-1290. · 0.50 Impact Factor
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ABSTRACT: Sabarubicin (MEN-10755), a new synthetic anthracycline analogue, was evaluated for safety and efficacy in a multicentre phase II study in patients with advanced hormone refractory prostate cancer (HRPC). Thirty seven patients were included, of which 34 were evaluable for PSA response according to Bubley's criteria. Sabarubicin was administered as a short (30 min) intravenous infusion at a dose of 80 mg/m(2) every 3 weeks. The main toxicity consisted of grade 3/4 neutropenia in 24 patients (64.9%), with grade 3/4 febrile neutropenia occurring in one patient only. Grade 3/4 cardiotoxicity was observed in 4 patients including one ineligible. Other toxicities were mild. Nine patients achieved a PSA response (26.5%), 10 patients had stable disease (29.4%) and 14 patients disease progression (41.2%). One patient (2.9%) had a PSA response that was not confirmed by repeat PSA testing. The objective response rate according to RECIST criteria was 6.7% in 15 patients with measurable disease. The median duration of PSA responses was relatively long 7.1 months (95% CI 4.9-20.7) as was the median time to treatment progression in patients with stable disease. The median overall survival was 18.7 months (95% CI 9.1-N), comparable to results recently observed in taxotere-containing regimens. To confirm and extend these results, further testing of sabarubicin in larger trials is warranted.
European Journal of Cancer 02/2006; 42(2):200-4. · 5.54 Impact Factor
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ABSTRACT: Increased vessel density in the bone marrow of patients with acute myeloid leukemia as well as elevated expression of proangiogenic factors by leukemic cells implies a central role of angiogenesis in hematological malignancies. Endostatin (ES), a fragment of collagen XVIII, is an endogenous inhibitor of angiogenesis that has shown therapeutic activity in solid tumors in various preclinical models. Using microencapsulation technology, we studied the therapeutic effect of ES in AML. While ES had no effect on proliferation of M1 murine leukemic cells in vitro, ES producing microbeads significantly inhibited growth of subcutaneous chloromas in SCID mice as compared to controls. In a leukemia model using M1 cells the concomitant treatment of mice with ES microbeads prolonged median survival significantly. Histological analysis revealed a decreased microvessel density and a reduced number of CD31-positive single cells, putatively endothelial progenitor cells, in the bone marrow of treated animals. Taken together, ES has inhibitory effects on neo-angiogenesis in the bone marrow and on progression of leukemia in vivo. These experiments suggest a possible therapeutic role of antiangiogenic gene therapy with ES in AML.
Leukemia 09/2005; 19(8):1312-7. · 9.56 Impact Factor
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C Theodore,
L Geoffrois,
J B Vermorken,
F Caponigro, W Fiedler,
P Chollet,
A Ravaud,
G J Peters,
C de Balincourt,
D Lacombe,
P Fumoleau
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ABSTRACT: In this study, the feasibility and activity of combined chemotherapy of the farnesyl transferase inhibitor SCH66336 and gemcitabine was evaluated. This therapy was used as second-line treatment in patients with advanced urothelial tract cancer and the influence of SCH66336 exposure on the pharmacokinetics of gemcitabine was also determined. Patients who had received one previous chemotherapy regime for advanced urothelial cancer were treated with a combination of SCH66336 (150 mg in the morning and 100 mg in the evening) and Gemcitabine (1000 mg/m2 on day 1, 8 and 15 per 28-day cycle). Dosages of gemcitabine and its metabolite dFdU were performed on day one of cycle 1 before exposure to SCH66336 and day one of cycle 2. A total of 152 cycles were administered in 33 patients (median 3, range: 1-15). No patients had severe hematological toxicity, defined as Grade 4 thrombocytopenia or febrile neutropenia. Nine partial responses and one complete response were achieved in 31 assessable patients and corresponded to an overall response rate of 32.3% [95% CI:17%-51%]. There was no influence of exposure to SCH66336 on the level of gemcitabine or dFdU in 11 assessable patients. In conclusion, a combination of SCH66336 and gemcitabine is feasible in terms of toxicity and active as second-line treatment in patients with advanced urothelial tract cancer. SCH66336 had no effect on the pharmacokinetics of gemcitabine. Randomised trials should be undertaken to clarify the role of SCH66336 in combination with gemcitabine in cancer treatment.
European Journal of Cancer 06/2005; 41(8):1150-7. · 5.54 Impact Factor
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ABSTRACT: Camptothecins have shown efficacy in terms of response rate in patients with small cell lung cancer (SCLC). RFS2000 is a new camptothecin derivative, which has shown objective responses in various tumour types. The aim of this phase II study was to determine the objective response rate of RFS2000 in patients with sensitive and refractory SCLC. RFS2000 was given orally at 1.5 mg/m(2) per day for five consecutive days (five days on - two days off) on a continuous basis. Patients were evaluated weekly for toxicity and every six weeks for response. Thirty seven patients were included, 36 patients (14 with sensitive and 22 with refractory SCLC) were evaluable for toxicity, and 35 patients were evaluable for response. No objective responses were observed. Toxicity was acceptable, with myelosuppression, nausea/vomiting, and diarrhoea as the main toxicities. RFS2000 therefore has an acceptable toxicity profile but is not active as a single agent in SCLC.
European Journal of Cancer 07/2004; 40(9):1332-4. · 5.54 Impact Factor
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ABSTRACT: A 21-year-old patient was admitted to the hospital because of massively enlarged cervical lymph nodes. Additionally, a left-sided facial and brachial edema was visible. Auscultation of the left lung was remarkable for diminished breath sounds.
Diagnostic imaging showed an extensive thoracic tumor and enlarged mediastinal and cervical lymph nodes. The diagnosis of neuroblastoma was established by biopsy.
The patient was treated with a polychemotherapy protocol according to the pediatric neuroblastoma study NB97. Subsequently, the patient underwent partial tumor resection, received two further chemotherapy courses and irradiation of the remaining tumor. Because of residual vital tumor cells, a second surgical tumour reduction followed by high-dose chemotherapy with autologous stem-cell support was performed. Two cycles of high-dose retinoic acid followed. Six months after the end of therapy, the patient is in a good condition despite of the presence of residual tumor.
Neuroblastoma is a very rare tumor in adult patients. Therapy is multimodal and should follow pediatric guidelines for neuroblastoma treatment.
DMW - Deutsche Medizinische Wochenschrift 03/2004; 129(6):249-52. · 0.53 Impact Factor
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E Laack,
A Köhler,
C Kugler,
T Dierlamm,
C Knuffmann,
G Vohwinkel,
A Niestroy,
N Dahlmann,
A Peters,
J Berger, W Fiedler,
D K Hossfeld
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ABSTRACT: Matrix metalloproteinase (MMP)-9 and vascular endothelial growth factor (VEGF) are two proteins involved in angiogenesis. In the present study we investigated the association of pretreatment MMP-9 and VEGF serum levels with clinicopathological parameters and outcome in patients with non-small-cell lung cancer (NSCLC).
From February 1998 to October 1999, pretreatment serum levels of MMP-9 and VEGF were analysed in 118 patients with enzyme-linked immunoassays. At diagnosis 50 patients (42%) were staged as early disease (I/II), 27 patients (23%) as locally advanced (IIIA/IIIB), and 41 patients (35%) had metastatic disease (IV). In 72 of the 118 patients tumours were resected and 46 patients received combination chemotherapy with gemcitabine and vinorelbine.
The median survival of all 118 patients was 602 days. The 72 patients who had undergone surgery had a median survival of 972 days and the 46 patients who were treated with chemotherapy had a median survival of 298 days (P <0.001). Resected patients with stage I/II disease and an MMP-9 serum level <or=1293 ng/ml or a VEGF serum level <or=630 pg/ml had a significantly longer survival (median survival longer than 1218 days) than patients with higher serum levels (median survival 421 days) (P = 0.001 for MMP-9; P = 0.04 for VEGF). No significant difference in survival was observed in patients with resected stage III disease. Besides tumour stage, Karnofsky performance status and gender, the pretreatment serum level of MMP-9 was identified as an independent prognostic factor in a multivariate Cox regression analysis.
Future studies may support our hypothesis that the pretreatment serum level of MMP-9 is a new powerful prognostic marker and can help to stratify NSCLC patients with stage I/II disease into low- and high-risk groups.
Annals of Oncology 10/2002; 13(10):1550-7. · 6.43 Impact Factor
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ABSTRACT: Phosphatidylinositol (PI) 3-kinase plays an important role in a variety of biological processes, including proliferation and apoptosis. PI3-kinase is a heterodimer consisting of an 85 kDa adapter protein (p85) containing one SH3 domain and two SH2 domains and a 110 kDa catalytic subunit (p110). Recently an oncogenic form of p85 named p65-PI3K lacking the C-terminal SH2 domain has been cloned from an irradiation-induced murine thymic lymphoma and transgenic mice expressing p65-PI3K in T lymphocytes develop a lymphoproliferative disorder. Here we describe the cloning of a C-terminal truncated form of p85 expressed in a human lymphoma cell line (CO) with a T cell phenotype derived from a patient with Hodgkin's disease. As a result of a frame-shift mutation at amino acid 636, p76 is lacking most of the C-terminal SH2 domain, but contains the inter-SH2 domain and is associated with an active form of PI3-kinase. A PI3-kinase-dependent constitutive activation of Akt was detected in CO cells which was only partially reduced after serum starvation. Treatment of CO cells with the PI3-kinase inhibitor wortmannin resulted in a concentration-dependent inhibition of cell proliferation associated with an increased number of apoptotic cells. This is the first detection of a mutated form of the p85 subunit of PI3-kinase in human hematopoietic cells further underlining a potential role of PI3-kinase/Akt signaling in human leukemogenesis.
Leukemia 06/2002; 16(5):894-901. · 9.56 Impact Factor
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ABSTRACT: IgM myeloma is a rare disease, accounting for approximately 0.5% of multiple myelomas (MM). Here we report four cases of IgM multiple myeloma. Two were diagnosed in advanced clinical stages with multiple osteolytic lesions, leading to hypercalcemia in one patient. Bone marrow morphology showed a variable degree of infiltration with mainly mature plasma cells. An immunophenotypic analysis performed in one case showed expression of CD38 and monoclonal cytoplasmatic immunoglobulin. Interphase fluorescence in situ hybridization performed in one case did not reveal any aneuploidies or deletions of the retinoblastoma, P16, or P53 tumor suppressor genes. While one patient with a smoldering IgM myeloma did not need specific therapy, the others received cytotoxic treatment based on standard chemotherapy for MM. The outcomes were one stable disease, one sustained complete remission, and one progressive disease. All four patients were alive 1 year after diagnosis. One died due to progressive disease after 31 months. We conclude that IgM myeloma shares clinical and histological features with other MM rather than with Waldenström's macroglobulinemia, which is most commonly diagnosed in cases with IgM monoclonal gammopathy. Since MM and Waldenström's macroglobulinemia differ in prognosis and treatment strategies, the two disease entities should be distinguished based on clinical criteria, bone marrow morphology, and immunophenotypic analysis.
Annals of Hematology 04/2002; 81(3):136-9. · 2.62 Impact Factor
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B Coudert,
A Anthoney, W Fiedler,
J P Droz,
V Dieras,
M Borner,
J F Smyth,
R Morant,
M J de Vries,
M Roelvink,
P Fumoleau
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ABSTRACT: Two multicentre phase II trials were designed to determine if tumour responses can be achieved in progressive small-cell lung cancer (SCLC) or non-small cell lung cancer (NSCLC) patients treated with ISIS 5132, an inhibitor of C-raf kinase mRNA expression (CGP 69846A; ISIS Pharmaceuticals Inc, Carlsbad, CA), and to further characterise the safety of the compound. Between August 1998 and November 1999, 26 patients (18 NSCLC, 8 SCLC) were entered. Out of these, 23 were eligible, 22 (18 NSCLC, 4 SCLC) were treated with ISIS 5132 (2 mg/kg/day, 21 days continuous intravenous (i.v.) infusion every 4 weeks) and were evaluable for toxicity and 18 (15 NSCLC, 3 SCLC) were evaluable for efficacy. For the whole group haematological toxicity did not exceed grade 2. One patient experienced a grade 4 increased prothrombin time. Non-haematological toxicity was mild to moderate, with the observation of asthenia and nausea and vomiting. Progressive disease (PD) was diagnosed in 10 patients (8 NSCLC and 2 SCLC). 8 more patients (7 NSCLC, 1 SCLC) were considered as treatment failures. In conclusion, this study using ISIS 5132 with this dose and schedule of administration excludes a 20% response rate with 95% confidence intervals for NSCLC and cannot draw any conclusions for SCLC patients as only a few were involved in the study.
European Journal of Cancer 12/2001; 37(17):2194-8. · 5.54 Impact Factor
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ABSTRACT: Endothelial cells and fibroblasts are important constituents of the haemopoietic microenvironment. Growth and function of these cells are controlled by a variety of cytokines, including vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF). We analysed the effects of novel tyrosine kinase inhibitors targeting the VEGF and PDGF receptors (compounds SU5614 and SU5768) on the performance of long-term cultures from normal human bone marrow. In developing cultures, the inhibitors induced a dose-dependent reduction in stromal fibroblasts, macrophages and endothelial cells with a concomitant decrease in blood cell production and an increase in fat cells. For SU5614, the concentration inhibiting stroma formation by 50% (IC50) was 123nM, and the IC50 for haemopoietic colony forming cell output was 186 nM. For SU5768, the respective values were 871 nM and 331 nM. Changes in stroma composition and inhibition of haemopoietic cell production were also demonstrable after delayed addition of the inhibitors to established cultures. By contrast, haemopoietic colony formation in clonogenic agar cultures was unimpaired (IC50 not reached at 100 microM). Immunofluorescence studies and time course analyses suggested that the primary effect of the inhibitors was interference with the proliferation and function of fibroblasts and endothelial cells which in turn resulted in decreased haemopoiesis and increased adipogenesis. This was associated with decreased levels in conditioned media of granulocyte-macrophage colony-stimulating factor, interleukin-6 and leptin. VEGF and PDGF may play a hitherto underestimated role in the control of blood cell formation. VEGF/PDGF receptor inhibitors may have therapeutic potential in stroma diseases such as myelofibrosis. Since they weaken the stimulatory signals provided by the microenvironment, they may also be of value in the treatment of leukaemia and other neoplastic bone marrow diseases.
Growth Factors 02/2001; 19(1):1-17. · 1.65 Impact Factor
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N Kröger,
T Zabelina,
S Sonnenberg,
W Krüger,
H Renges,
N Stute,
F Finkenstein,
U Mayer,
K Holstein, W Fiedler,
H Colberg,
R Sonnen,
R Kuse,
D Braumann,
B Metzner,
F del Valle,
R Erttmann,
H Kabisch,
A R Zander
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ABSTRACT: To evaluate the efficacy and toxicity of two different etoposide (VP-16) dosages (30 or 45 mg/kg) in combination with busulfan/cyclophosphamide as conditioning therapy followed by stem cell transplantation in acute myeloid leukemia (AML), 90 patients with AML received either 30 mg/kg (n = 60) or 45 mg/kg (n = 30) etoposide in combination with busulfan (16 mg/kg) and cyclophosphamide (120 mg/kg). The stem cell source was allogeneic related bone marrow (BM) (n = 53), allogeneic unrelated BM (n = 5), allogeneic unrelated peripheral blood (PBSC) (n = 2), syngeneic BM (n = 2), autologous BM purged (n = 9) or unpurged (n = 9), autologous PBSC (n = 10). Fifty-six patients (62%) were in first CR, 26 (29%) were > first CR, and eight (9%) were transplanted in relapse. Principal toxicities in both groups were mucositis and hepatotoxicity. Forty-five mg/kg etoposide resulted in greater hepatic toxicity (P = 0.03), and a higher incidence of VOD (23 vs 12%, P = 0.04) and acute GVHD grade III/IV (13 vs 5%, NS). The treatment-related mortality was 17% in the 30 mg/kg group and 33% in the 45 mg/kg group, mainly due to infections, intestinal pneumonia and GVHD. Hematological recovery of leukocytes 1/nl was comparable in both groups (17 vs 16 days). After a median follow-up of 16 months 19% in the 30 mg/kg group and 23% in the 45 mg/kg group relapsed. In patients who had undergone allogeneic related bone marrow transplantation in first CR no relapses occurred after a median follow-up of 3 years. For all patients the 3-year estimated disease-free survival was 62% in the 30 mg/kg group and 40% in the 45 mg/kg group (P = 0.03). For patients in first CR who underwent allogeneic related stem cell transplantation the 3 year disease-free survivals were 80% and 66%, respectively (P = 0.4). We conclude that etoposide 30 mg/kg or 45 mg/kg in combination with busulfan/cyclophosphamide is a highly active regimen for bone marrow transplantation of patients with AML with a low relapse rate. However, conditioning with 30 mg/kg rather than 45 mg/kg etoposide resulted in less toxicity and a better overall survival due to a lower transplant-related mortality. Bone Marrow Transplantation (2000) 26, 711-716.
Bone Marrow Transplantation 11/2000; 26(7):711-6. · 3.75 Impact Factor
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U M Gehling,
S Ergün,
U Schumacher,
C Wagener,
K Pantel,
M Otte,
G Schuch,
P Schafhausen,
T Mende,
N Kilic,
K Kluge,
B Schäfer,
D K Hossfeld, W Fiedler
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ABSTRACT: Recent findings support the hypothesis that the CD34(+)-cell population in bone marrow and peripheral blood contains hematopoietic and endothelial progenitor and stem cells. In this study, we report that human AC133(+) cells from granulocyte colony-stimulating factor-mobilized peripheral blood have the capacity to differentiate into endothelial cells (ECs). When cultured in the presence of vascular endothelial growth factor (VEGF) and the novel cytokine stem cell growth factor (SCGF), AC133(+) progenitors generate both adherent and proliferating nonadherent cells. Phenotypic analysis of the cells within the adherent population reveals that the majority display endothelial features, including the expression of KDR, Tie-2, Ulex europaeus agglutinin-1, and von Willebrand factor. Electron microscopic studies of these cells show structures compatible with Weibel-Palade bodies that are found exclusively in vascular endothelium. AC133-derived nonadherent cells give rise to both hematopoietic and endothelial colonies in semisolid medium. On transfer to fresh liquid culture with VEGF and SCGF, nonadherent cells again produce an adherent and a nonadherent population. In mice with severe combined immunodeficiency, AC133-derived cells form new blood vessels in vivo when injected subcutaneously together with A549 lung cancer cells. These data indicate that the AC133(+)-cell population consists of progenitor and stem cells not only with hematopoietic potential but also with the capacity to differentiate into ECs. Whether these hematopoietic and endothelial progenitors develop from a common precursor, the hemangioblast will be studied at the single-cell level.
Blood 06/2000; 95(10):3106-12. · 9.90 Impact Factor
