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  • 1
    In: Blood, American Society of Hematology, Vol. 104, No. 1 ( 2004-07-01), p. 81-88
    Abstract: Recently, overlapping molecular phenotypes of hematopoietic and neuropoietic cells were described in mice. Here, we examined primary human CD34+ hematopoietic stem and progenitor cells applying specialized cDNA arrays, real-time reverse-transcriptase–polymerase chain reaction (RT-PCR), and fluorescent-activated cell sorter (FACS) analysis focusing on genes involved in neurobiologic functions. We found expression of vesicle fusion and motility genes, ligand- and voltage-gated ion channels, receptor kinases and phosphatases, and, most interestingly, mRNA as well as protein expression of G protein–coupled receptors of neuromediators (corticotropin-releasing hormone 1 [CRH 1] and CRH 2 receptors, orexin/hypocretin 1 and 2 receptors, GABAB receptor, adenosine A2B receptor, opioid κ1 and μ1 receptors, and 5-HT 1F receptor). As shown by 2-color immunofluorescence, the protein expression of these receptors was higher in the more immature CD38dim than in the CD38bright subset within the CD34+ population, and completely absent in fully differentiated blood cells, suggesting that those receptors play a role in developmentally early CD34+ stem and progenitor cells. The intracellular concentration of cyclic adenosine monophosphate (cAMP) in CD34+ cells was diminished significantly upon stimulation of either CRH or orexin receptors, indicating that those are functionally active and coupled to inhibitory G proteins in human hematopoietic cells. In conclusion, these findings suggest a molecular interrelation of neuronal and hematopoietic signaling mechanisms in humans.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
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    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2004
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  • 2
    Online Resource
    Online Resource
    Springer Science and Business Media LLC ; 2002
    In:  Cancer Gene Therapy Vol. 9, No. 7 ( 2002-07-01), p. 587-596
    In: Cancer Gene Therapy, Springer Science and Business Media LLC, Vol. 9, No. 7 ( 2002-07-01), p. 587-596
    Type of Medium: Online Resource
    ISSN: 0929-1903 , 1476-5500
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2002
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  • 3
    In: Blood, American Society of Hematology, Vol. 108, No. 11 ( 2006-11-16), p. 4866-4866
    Abstract: The biology of myelodysplastic syndromes (MDS) is reflected in aberrant transcription levels of the myeloid lineage. It was the purpose of this study to provide potential novel therapeutic targets by identifying molecular alterations that are pertinent to myelodysplastic syndromes. cDNA from bone marrow-derived CD34+ hematopoietic stem and progenitor cells from 6 healthy persons, and 16 patients with MDS (Table 1) was hybridized to cDNA arrays comprising 1185 well-characterized genes. We used the complete cDNA array expression values to build a dendrogram including all samples under investigation. Interestingly, patient survival had a striking impact on our gene signature for it was the parameter that had the strongest statistical association with the segregation of our MDS patients into 2 sub clusters (Figure 1). We examined whether this segregation of MDS patients was associated with age, gender, MDS-type according to FAB, WHO, IPSS, karyotype or survival. We determined correlation coefficients and found “survival” to be the parameter with the strongest statistically significant association with the segregation of MDS patients into 2 sub clusters (Spearman = 0.697, P = 0.003). The WHO type was less significantly associated (Spearman = 0.537, P = 0.032), and the FAB type did not reach statistical significance (Spearman = 0.492, P = 0.053). Transcriptional changes that are associated with short survival may also indicate to potential novel therapeutic targets. Since median age of patients with MDS is 70 at diagnosis, the majority of patients are not suitable for therapies that are not well tolerated. Moreover, some patients have a nearly normal life expectancy. Ideally, new therapeutic agents should, therefore, be tailored for patients with short survival and be well-tolerated like e.g. Bevacizumab and Cetuximab. But, we could not find increased expression of Bevacizumab and Cetuximab related EGFR- or VEGFR-target genes in CD34+ cells from MDS patients with short survival. In sum, there are transcriptional alterations that are strongly associated with short survival, and thus valuable for prognostication of patients with MDS. Table 1. Classification, and karyotypes of patients with MDS who were analyzed by means of cDNA array analysis Patient No. Age/ Sex FAB (a) IPSS (b) WHO (c) Karyotype (a) FAB, French-American-British cooperative group classification, (b) IPSS, international prognostic scoring system; int, intermediate, (c) WHO, World Health Organization classification 1 61/ F RA int-I RCMD 46, XX, 13q- 2 68/ F RA int-I 5q- 46, XX, 5q-, 12p- 3 62/ M RA int-I RCMD 47, XY, +8 4 50/ M RA int-I RCMD 46, XY, t(X;1) 5 18/ F RA low PRA 46, XX 6 51/ M RA low RCMD 46, XY 7 51 /F RA int-I 5q- 46, XX, 5q-, 12p 8 75/ M RAEB high RAEB II 46, XY, 7q- 9 79/ M RAEB-t high sAML complex 10 68/ M RAEB int-II RAEB-II 46, XY 11 70/ F RAEB-t high sAML 46, XX, 15q- 12 52/ M RAEB-t high sAML complex 13 72/ M RAEB-t high sAML complex 14 75/ M RAEB int-I RAEB-I 46, XY 15 72/ M sAML/MDS - sAML complex 16 76/ M sAML/MDS - sAML 46, XY Dendrogram derived from hierarchical cluster analysis using the 1-correlation distance metrics and an average linkage algorithm. Dendrogram derived from hierarchical cluster analysis using the 1-correlation distance metrics and an average linkage algorithm.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
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    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2006
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  • 4
    In: Blood, American Society of Hematology, Vol. 108, No. 11 ( 2006-11-16), p. 3540-3540
    Abstract: Bortezomib has improved the outcome of patients with multiple myeloma. Nevertheless, bortezomib monotherapy achieves responses in less than 50% of patients with advanced disease. Combination therapy can improve response rates but is associated with more adverse events such as neuropathy or myelosuppression. Therefore, we evaluated a step-wise escalation treatment algorithm for patients with relapsed or refractory myeloma. The initial treatment (step1) consisted of bortezomib monotherapy (1.3mg/m2 on day 1,4,8,11). Patients who did not show a at least 25% reduction of paraprotein at the beginning of cycle 2 received an escalated treatment (step2) with bortezomib and dexamethasone (40mg on day 1,4,8,11). The next treatment escalation (step3) was performed by addition of bendamustine (50–100mg/m2 on day 1 + 8) to bortezomib and dexamethasone. Step3 was used for patients who did respond with less than a minor response to one cycle of step2 treatment. We report on 48 patients who have been treated at our institution according to this regimen. Patients median age was 59 years with a median β2-microglobuline level of 3.8 g/dl and median albumine level of 3.7 g/dl. All patients were heavily pre-treated with in median three prior treatment regimen including high-dose therapy and thalidomide in more than 90% of patients. Escalation therapy was applied as planned to 36 (75%) patients, whereas 12 (25%) patients received step2 at the beginning of treatment due to physicians decision because of fulminant disease progression with hypercalcemia or severe tumor burden. Toxicity was as expected for bortezomib monotherapy and was manageable with escalated treatment steps. Response rates for patients in step1 were 11% nCR, 36% PR and 11% MR. In step2 (n=26) response rates were 31% PR, 15% MR and in step3 (n = 7) 43% PR and 29% MR. This results in an overall response rate of 80% for all patients. Patients with fulminant progressive disease who needed upfront treatment with step2 had an inferior overall response rate of 42% in comparison to 90% for patients who were treated according to the planned treatment schedule. With a median follow-up of 26 months the median time to progression and overall survival was 9 months and not reached for patients in the planned program and 2 and 4 months for the patients with upfront escalated therapy. Univariate analysis including several conventional prognostic parameters revealed physicians decision for upfront escalated treatment and age 〉 60 years as the only bad prognostic factors. Interestingly, for patients within the planned treatment schedule, response to previous therapies, the extent of paraprotein reduction and the required escalation step had no impact on response duration. Another interesting observation of our single center study was that re-exposure of step3 treatment at the time of relapse (n=8) resulted in a new remission in 50% and in stable disease in 38% of patients. In conclusion, escalating therapy with bortezomib, dexamethasone and bendamustine induces durable remissions in the majority of patients, even in the presence of poor prognostic parameters. However, this treatment algorithm is not applicable for patients presenting with fulminant disease progression, as these patients need more aggressive regimens.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
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    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2006
    detail.hit.zdb_id: 1468538-3
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  • 5
    In: Blood, American Society of Hematology, Vol. 104, No. 11 ( 2004-11-16), p. 2868-2868
    Abstract: To date the most effective treatment for patients (pts) with multiple myeloma consists of conventional induction chemotherapy followed by either single or tandem high-dose chemotherapy and autologous blood stem cell transplantation. Collection of sufficient numbers of hematopoietic stem cells is essential for high-dose chemotherapy. Current regimens for stem cell mobilization are based on daily subcutaneous injections of human recombinant G-CSF starting shortly after cytotoxic therapy. Here we examined the use of polyethyenglycole (PEG)-conjugated G-CSF (pegfilgrastim) at two different doses in patients with stage II or III multiple myeloma. Patients received induction therapy with 2–4 cycles ID or VAD. Following cytotoxic therapy with cyclophosphamide (4g/m2) we administered either a single dose of 6 mg pegfilgrastim (n=10 pts; median age: 55 years), 12 mg pegfilgrastim (n=12 pts; median age: 51 years) or daily doses of 8,5 μg/kg unconjugated G-CSF (filgrastim) (n=12 pts; median age: 51 years). The growth factor was given on day 4 (range 2–5 days) in the “6 mg pegfilgrastim group”, on day 5 (range 2–7 days) in the “12 mg pegfilgrastim group” and on day 4 (range 3–6 days) in the “filgrastim group” after cyclophosphamide. Numbers of CD34+ cells were determined during leukocyte recovery and harvested by large volume apheresis using a cobe spectra blood cell separator. Pegfilgratim was associated with an earlier leukocyte recovery both at the 6mg dose (median 12 days, range 8–16 days) and the 12mg dose (median 12 days, range 7–16 days) as compared to filgrastim (median 14 days, range 11–15 days, p=0.04). Similarily, the peripheral blood CD34+ cell peak occurred earlier in patients who received pegfilgrastim (median 12 days, range 11–18 days versus median 15 days, range 12–18). On the other hand the peripheral blood CD 34+ peak did not differ significantly between the three groups (median 129/μl with 6 mg pegfilgrastim, range 30–433, median 78/μl with 12 mg pegfilgrastim, range 20– 1055 and median 111/μl with filgrastim, range 28–760, p=0.95). With a median of 1.0x10E7 CD34+ cells per kg (range 5.8x10E6-1.9x10E7) in the “6 mg pegfilgrastim group”, 7.4x10E6 CD34+ cells per kg (median, range 4.9x10E6- 3.8x10E7) in the “12 mg pegfilgrastim group” and 10.8x10E6 CD34+ cells per kg (median, range 5.0x10E6-8.7x10E7) in the “filgrastim group” there were no significant differences in the total number of harvested CD34+ cells. Following high-dose therapy with melphalan (200 mg/m2) and autografting leukocyte and platelet reconstitution was similar within all groups. In summary, a single dose of pegfilgrastim after high dose cyclophosphamide is capable of mobilizing a sufficient number of CD 34+ cells for succesful autografting and sustained hematological reconstitution in patients with multiple myeloma. No difference could be observed between 6 mg and 12 mg of pegfilgrastim. Our data provide the basis for randomized studies evaluating the optimal dose and timing of pegfilgrastim as well as long-term outcome in larger cohorts of patients.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
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    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2004
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  • 6
    In: Blood, American Society of Hematology, Vol. 91, No. 3 ( 1998-02-01), p. 852-862
    Abstract: The use of antisense oligodeoxyribonucleotides (ODN) is a potential method to switch off gene expression. The poor cellular uptake of ODN in primary cells still is a limiting factor that may contribute to the lack of functional efficacy. Various forms of cationic lipids have been developed for efficient delivery of nucleic acids into different cell types. We examined the two cationic lipids DOTAP and DOSPER to improve uptake of ODN into primary human hematopoietic cells. Using a radiolabeled 23-mer, ODN uptake into blood-derived mononuclear cells could be increased 42- to 93-fold by DOTAP and 440- to 1,025-fold by DOSPER compared with application of ODN alone. DOTAP was also effective for delivery of ODN into leukocytes within whole blood, which may resemble more closely the in vivo conditions. As assessed by fluorescein isothiocyanate–conjugated ODN both cationic lipids enhanced cytoplasmic accumulation of ODN in endosome/lysosome-like structures with a partial shift of fluorescence to the whole cytoplasm and the nucleus following an incubation of 24 hours. ODN uptake by cationic lipids into different hematopoietic cell subsets was examined by dual-color immunofluorescence analysis with subset-specific monoclonal antibodies. We found a cell type–dependent delivery of ODN with greatest uptake in monocytes and smallest uptake in T cells. CD34+ cells, B cells, and granulocytes took up ODN at an intermediate level. Uptake of ODN into isolated CD34+cells could be increased 100- to 240-fold using cationic lipids compared with application of ODN alone. Stimulation of CD34+ cells by interleukin-3 (IL-3), IL-6, and stem cell factor did not significantly improve cationic lipid-mediated ODN delivery. Sequence-specific antisense effects in clonogenic assays could be shown by transfection of bcr-abl oncogene-directed antisense ODN into primary cells of patients with chronic myelogenous leukemia using this established protocol. In conclusion, cationic lipids may be useful tools for delivery of antisense ODN into primary hematopoietic cells. These studies provide a basis for clinical protocols in the treatment of hematopoietic cells in patients with hematologic malignancies and viral diseases by antisense ODN.
    Type of Medium: Online Resource
    ISSN: 1528-0020 , 0006-4971
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    Language: English
    Publisher: American Society of Hematology
    Publication Date: 1998
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  • 7
    In: Blood, American Society of Hematology, Vol. 110, No. 11 ( 2007-11-16), p. 3170-3170
    Abstract: During the last decade, chronic myeloid leukemia (CML) has been mainly characterized by the reciprocal translocation between chromosomes 9 and 22, resulting in the formation of the protooncogene BCR-ABL. This constitutively active tyrosine kinase is widely considered as the cause of the disease. Even though BCR-ABL transcripts are found in every dividing hematopoietic cell and thus, the disease is likely to originate from a primitive stem cell, the “cell of origin” is still a matter of debate. Despite the active “leukemia stem cell” discussion, very few characteristics of the “cancer stem cell” are established to date. In order to get further molecular insights into CML stem and progenitor cells, we examined CD34+ cell subsets obtained from bone marrow of 7 patients with CML in chronic phase in comparison with 5 healthy volunteers. CD34+ cells were immunomagnetically selected and high-speed cell sorting of lineage-negative, CD34+, CD38−, hematopoietic stem cells and myeloid progenitors was performed. Progenitors were further subdivided by anti-IL-3Ralpha and anti-CD45RA staining. Following RNA extraction, a two-cycle amplification procedure was used to generate cDNA for the hybridization with Affymetrix U133A2.0 arrays. After performing smoothening spline normalization, we applied the perfect match-mismatch difference model algorithm to calculate expression values (dChip). Hierarchical cluster analysis was performed using a correlation based centroid linkage algorithm. Hereby we could discriminate the HSCs, CMPs, and MEP subsets. Corroboration of RNA expression was performed by real-time RT-PCR for selected genes. Comparing the HSC subsets of CML patients with healthy controls we found 98 differentially expressed genes. 87 genes had a lower expression level in CML HSCs whereas 11 genes had a higher one. Among the downregulated genes in CML were transcriptions factors involved in myelogenesis and proliferation and several adhesion molecules associated with homing and migration of the HSCs. On the other hand, the Leptin receptor and BCR-ABL downstream targets were found to be upregulated. Within the common myeloid progenitor (CMP) compartment 37 genes were significantly differentially regulated. Twenty genes had a higher expression level in CML CMPs, 17 genes were downlegulated. Hematopoietic cell-specific cell cycle inhibitor MS4A3 was among the significantly downregulated genes whereas genes of the retinoblastoma and E2F families as well as inhibitors of the Wnt-signaling pathway were upregulated. Looking at megakaryocte-erythrocyte progenitors (MEP) in CML, key mediators of G2-M cell cycle transition were downregulated indicating a lower proliferative capacity of this subset. No transcriptional differences have been observed between granulocyte-macrophage progenitors from CML patients and healthy volunteers. Interestingly, among all other subsets myeloperoxidase (MPO) was downregulated in the CML samples and the Leptin receptor was upregulated. Our results provide novel insights into the biology of CML and potentially provide the basis for the characterization of a candidate CML stem cell.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
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    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2007
    detail.hit.zdb_id: 1468538-3
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  • 8
    In: Blood, American Society of Hematology, Vol. 106, No. 11 ( 2005-11-16), p. 5191-5191
    Abstract: Background: Current regimens for peripheral blood stem cell (PBSC) mobilization in patients with multiple myeloma are based on daily subcutaneous injections of G-CSF starting shortly after cytotoxic therapy. Recently a polyethylenglycole (PEG)-conjugated G-CSF (pegfilgrastim) has been introduced which has a substantially longer half-life than the original formula. Here, we compared the molecular phenotypes of CD34+ stem and progenitor cells mobilized by G-CSF with those mobilized by pegfilgrastim. Study design and Methods: We examined immunomagnetically enriched CD34+ cells from leukapheresis products of 8 patients who received G-CSF and of 8 patients who were given pegfilgrastim using Affymetrix HG Focus GeneChips covering 8793 genes. The statistical scripting language ‘R’ was used for data analysis. Significantly differentially expressed genes were identified with the Significance Analysis of Microarrays (SAM) algorithm. Results: Comparing CD34+ cells mobilized by G-CSF with pegfilgrastim-mobilized CD34+ cells 108 genes were differentially expressed (fold change 1.25 – 14.0, q- value 2.45–14.44%). 38 genes had a higher and 70 genes had a lower expression in CD34+ cells mobilized by G-CSF. We found upregulation of genes characteristic for erythropoietic differentiation including haemoglobin chains and Erythroid Kruppel-like factor in G-CSF-mobilized CD34+ cells. Utilizing clonogenic assays we were able to functionally corroborate this finding as G-CSF-mobilized cells gave rise to a significantly higher number of burst-forming units erythroid (BFU-E) as compared to colony forming units granulocyte-macrophage (CFU-GM) (p=0.016). Cell cycle regulating genes were differentially expressed as well. Genes encoding for proteins that cause cell cycle arrest including human HTm4 were upregulated in G-CSF-mobilized cells, as opposed to an upregulation of cell cycle-promoting genes including Cyclin D2 and Hepatocyte Leukemia Factor (HLF) in pegfilgrastim-mobilized cells. Moreover in pegfilgrastim-mobilized CD34+ cells we saw an upregulation of multiple genes involved in cellular immunogenicity like MHC class I and II antigens and genes encoding for proteins playing a role in antigen presentation. Conclusion: Unconjugated G-CSF seems to be associated with an increased mobilisation of erythroid progenitors or an induction of erythropoiesis. Pegfilgrastim might result in mobilization of more immunogenic CD34+ cells. Unconjugated G-CSF and pegfilgrastim both seem to have an effect on cell cycle. Unconjugated G-CSF might rather induce cell cycle arrest and pegfilgrastim seems to lead to an increase of the cell cycle activity. This may be due to potentially different effects of continuously high serum levels of G-CSF maintained by pegfilgrastim and the pulsatile daily G-CSF injections on CD34+ cells.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
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    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2005
    detail.hit.zdb_id: 1468538-3
    detail.hit.zdb_id: 80069-7
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  • 9
    In: Blood, American Society of Hematology, Vol. 99, No. 6 ( 2002-03-15), p. 2037-2044
    Abstract: CD34+ hematopoietic stem cells are used clinically to support cytotoxic therapy, and recent studies raised hope that they could even serve as a cellular source for nonhematopoietic tissue engineering. Here, we examined in 18 volunteers the gene expressions of 1185 genes in highly enriched bone marrow CD34+(BM-CD34+) or granulocyte–colony-stimulating factor–mobilized peripheral blood CD34+(PB-CD34+) cells by means of cDNA array technology to identify molecular causes underlying the functional differences between circulating and sedentary hematopoietic stem and progenitor cells. In total, 65 genes were significantly differentially expressed. Greater cell cycle and DNA synthesis activity of BM-CD34+ than PB-CD34+ cells were reflected by the 2- to 5-fold higher expression of 9 genes involved in cell cycle progression, 11 genes regulating DNA synthesis, and cell cycle–initiating transcription factor E2F-1. Conversely, 9 other transcription factors, including the differentiation blocking GATA2 and N-myc, were expressed 2 to 3 times higher in PB-CD34+ cells than in BM-CD34+cells. Expression of 5 apoptosis driving genes was also 2 to 3 times greater in PB-CD34+ cells, reflecting a higher apoptotic activity. In summary, our study provides a gene expression profile of primary human CD34+ hematopoietic cells of the blood and marrow. Our data molecularly confirm and explain the finding that CD34+ cells residing in the bone marrow cycle more rapidly, whereas circulating CD34+ cells consist of a higher number of quiescent stem and progenitor cells. Moreover, our data provide novel molecular insight into stem cell physiology.
    Type of Medium: Online Resource
    ISSN: 1528-0020 , 0006-4971
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    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2002
    detail.hit.zdb_id: 1468538-3
    detail.hit.zdb_id: 80069-7
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  • 10
    In: Blood, American Society of Hematology, Vol. 104, No. 11 ( 2004-11-16), p. 2955-2955
    Abstract: Treatment of chronic myelogenous leukemia (CML) with Imatinib has shown its efficacy and superiority to conventional therapies. Beside inhibition of BCR-ABL Imatinib also has inhibitory effects on other tyrosine kinases such as wild-type ABL, c-KIT and platelet-derived growth factor receptors (PDGF-R) alpha and beta which play a role in differentiation and proliferation of hematopoietic stem cells and are involved in DNA repair mechanisms. Inhibition of these genes might therefore result in functional disturbance of hematopoiesis or even in secondary karyotypic abnormalities. Therefore, we compared gene expression profiles of immunomagnetically isolated CD34+ bone marrow (BM) cells from six healthy volunteers with Ph negative CD34+ cells from BM of eight patients (6 males, 2 females; median age: 52 years, range: 25–68 years) with Ph positive CML in chronic phase who reached major molecular remission during imatinib therapy (400 mg/day; 28 months (range: 11–39 months)). Cytogenetics, FISH analysis and quantitative real-time RT-PCR for BCR-ABL transcripts showed that all patients were in complete cytogenetic and in major molecular remission ( ≥ 3 log reduction of the BCR-ABL/G6PDH ratio in comparison to pretreatment value). CD34+ cells (median: 5 x 105; range 2 x 105–1.8 x 106) were isolated immunomagnetically from bone marrow with a purity 〉 98%. Total RNA (median: 550 ng; range: 130 – 990 ng) from isolated CD34+ cells was used to generate biotin-labelled cRNA (median: 7.5 μg; range: 2.6–12.3 μg). Labeled cRNA was hybridized to Affymetrix HG-Focus GeneChips covering 8793 genes representing a broad spectrum of different functional groups. For normalization and data analysis we used the statistical scripting language “R”. Raw data were normalized using a method of variance stabilizing transformations (VSN). To compare the normalized data from CD34+ cells of imatinib-treated patients and healthy volunteers we used the Significance Analysis of Microarrays (SAM) algorithm v1.21. We found that CD34+ cells of patients after reaching major molecular remission during first-line treatment with 400 mg imatinib per day showed no significantly differentially expressed genes in comparison to CD34+ cells of healthy volunteers in vivo. There was no evidence for transcriptional changes of genes involved in DNA repair or oncogenesis supporting the view that secondary chromosomal aberrations in Ph negative hematopoiesis observed during imatinib therapy might not be induced by the tyrosine kinase inhibitor itself. Our data suggest that imatinib as first-line therapy might not result in a major functional disturbance of Ph negative hematopoiesis.
    Type of Medium: Online Resource
    ISSN: 0006-4971 , 1528-0020
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    Language: English
    Publisher: American Society of Hematology
    Publication Date: 2004
    detail.hit.zdb_id: 1468538-3
    detail.hit.zdb_id: 80069-7
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