Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0023473 (chronic myeloid leukemia)
 18,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The ABL-specific tyrosine kinase inhibitor STI571 (formerly CGP57148B) induced cytogenetic remissions in 33% of chronic myelogenous leukemia (CML) patients in a phase I trial (Druker et al 1999). Combination therapy may increase this proportion. We tested whether combinations of STI571 and cytarabine or other chemotherapeutic agents such as hydroxyurea, mafosfamide or etoposide would display synergistic activity in BCR-ABL-positive chronic myelogenous leukemia (CML) cell lines derived from patients in blast crisis. In addition, the toxicity of these combinations on BCR-ABL-negative cells was investigated. A tetrazolium-based MTT assay was used to quantity growth inhibition after 48 h of exposure to cytotoxic agents alone and in simultaneous combination with STI571. The drug interactions were analyzed using the median-effect method of Chou and Talalay. The combination index (CI) was calculated according to the classic isobologram equation. At growth inhibition levels of over 50%, STI571 + cytarabine as well as STI571 + etoposide were significantly synergistic (CI < 1, P < 0.05) in the BCR-ABL-positive cell lines evaluated. At 60% inhibition or higher, a similar synergistic pattern became apparent for STI571 + mafosfamide (P < 0.05), while STI571 + hydroxyurea showed ambiguous, cell line-dependent synergism (BV173), additivity (EM-3) or antagonism (K562) in CML cell lines. Furthermore, the BCR-ABL-negative HL-60, KG1a and normal CD34+ progenitor cells were not affected by 0.8 microM STI571, a concentration which produced more than 50% growth inhibition in all BCR-ABL-positive cells tested, and no potentiation of growth inhibition was observed in these BCR-ABL-negative cells when STI571 was combined with chemotherapeutic agents. Our in vitro data with CML blast crisis cell lines strongly suggest that combinations of STI571 with cytarabine or etoposide be rapidly considered for clinical testing.
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PMID:Synergistic activity of the new ABL-specific tyrosine kinase inhibitor STI571 and chemotherapeutic drugs on BCR-ABL-positive chronic myelogenous leukemia cells. 1123 55

The BCR/ABL tyrosine kinase has been implicated in the pathogenesis of chronic myelogenous leukemia (CML) and Philadelphia chromosome-positive (Ph(+)) acute lymphoblastic leukemia (ALL). STI571 is a novel anticancer agent that selectively inhibits the BCR/ABL tyrosine kinase. The cytotoxic effects of STI571 were studied in combination with antileukemic agents against Ph(+) leukemia cell lines, KU812, K-562, TCC-S, and TCC-Y. The cells were exposed to STI571 and to other agents simultaneously for 5 or 7 days. Cell growth inhibition was determined by MTT assay. The cytotoxic effects in combinations at the inhibitory concentration of 80% level were evaluated by the isobologram. STI571 produced synergistic effects with recombinant and natural alpha-interferons in 2 of 3 and 3 of 3 cell lines, respectively. STI571 produced additive effects with hydroxyurea, cytarabine, homoharringtonine, doxorubicin, and etoposide in all 4 cell lines. STI571 with 4-hydroperoxy-cyclophosphamide, methotrexate, or vincristine produced additive, antagonistic, and synergistic effects in 3 of 4 cell lines, respectively. These findings suggest that the simultaneous administration of STI571 with other agents except methotrexate would be advantageous for cytotoxic effects against Ph(+) leukemias. Among them, the simultaneous administration of STI571 and alpha-interferons or vincristine would be highly effective against Ph(+) leukemias and these combinations would be worthy of clinical trials. In contrast, the simultaneous administration of STI571 with methotrexate would have little therapeutic efficacy. Although there are gaps between in vitro studies and clinical trials, the present findings provide useful information for the establishment of clinical protocols involving STI571. (Blood. 2001;97:1999-2007)
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PMID:In vitro cytotoxic effects of a tyrosine kinase inhibitor STI571 in combination with commonly used antileukemic agents. 1126 64

Two new boron compoumds, dihydroxy(oxybiguanido) boron (iii) hydrochloride monohydrate (HB) and guanidine biboric acid adduct (GB) were used in this study to observe the antitumor effect. Leukemic blast cells isolated from chronic myeloid leukemia (CML) patients showed significant cell growth inhibition within twentyfour hours. IC50 of GB and HB was 2mg/ml. The metabolically active cells were found to be inhibited by drug treatment as assessed by MTT test. Inhibition of 3H Thymidine incorporation also supported the above result. In this study we investigated the molecular mechanisms by which HB and GB induce apoptosis in immature blast cells.
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PMID:Boron compounds against human leukemic cells. 1187 44

Dexrazoxane (DEX) prevents the formation of free radical, lipid peroxidation and cardiotoxicity caused by anthracyclines. Due to a concern about its possible interference with anthracyclin cytotoxicity, the in vitro effect of DEX on daunorubicin (DNR) cytotoxicity, cell cycle and induction of apoptosis by annexin-V was investigated. The sensitivity to DEX, DNR and their combination was tested by the MTT assay in human promyelocytic leukemia HL-60, the erythroid blast crisis CML K562 cell lines and in 45 children with ALL and AML. Cell cycle analysis and annexin-V expression were performed by flow cytometry. It has been observed that DEX itself weakly, but significantly caused cytotoxicity in both cell lines and in patient samples, especially in initial ALL samples. DEX sensitized K562 and HL60, but not patient samples, to cytotoxicity of DNR. The percentage of necrotic/apoptotic cells, as detected in cell cycle analysis and annexin V staining, was higher after exposure to DEX +/- DNR, when compared to respective samples not treated with DEX, in both cell lines but not in patient samples. Expression of annexin V induced by DEX in both cell lines was enlarged, regardless of the presence of DNR. This difference was not observed in patient samples, however, the number of cells expressing annexin V was higher after exposure to DEX +/- DNR in comparison to respective samples not treated with DEX. In conclusion, it seems that DEX possibly has no impact on the sensitivity of childhood leukemic blasts to DNR, however, has weak cytotoxic properties itself.
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PMID:Dexrazoxane has no impact on sensitivity of childhood leukemic blasts to daunorubicin. 1198 42

Arsenic trioxide (As(2)O(3)) was recently demonstrated to be an effective inducer of apoptosis in patients with relapsed acute promyelocytic leukemia (APL) as well as in patients with APL in whom all-trans-retinoic acid and conventional chemotherapy failed. Chronic myelogenous leukemia cells are highly resistant to chemotherapeutic drugs. To determine if As(2)O(3) might be useful for the treatment of chronic myelogenous leukemia, we examined the ability of As(2)O(3) to induce apoptosis in K562 cells. In vitro cytotoxicity of As(2)O(3) was evaluated in K562 cells by a MTT assay; the IC(50) value for As(2)O(3) was determined to be 10 microM. When analyzed by agarose gel electrophoresis, the DNA fragments became evident after incubation of the cells with 20 microM As(2)O(3) for 24 h. We also found morphological changes and chromatin condensation of the cells undergoing apoptosis. Activation of caspase-3 was observed 6 h after treatment with 20 microM As(2)O(3) by a Western blot analysis. Next, we examined the MAP kinase-signaling pathway of As(2)O(3)-induced apoptosis in K562 cells. As(2)O(3) at 10 microM strongly induced the activation of p38 and JNK 1/2, while ERK 1/2 was inhibited. In addition, pretreatment of SB203580, a specific inhibitor of p38, inhibited As(2)O(3) induced apoptotic cell death. These results suggest that As(2)O(3) is able to induce the apoptotic activity in K562 cells, and its apoptotic mechanism may be associated with the activation of p38.
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PMID:Arsenic trioxide induces apoptosis in chronic myelogenous leukemia K562 cells: possible involvement of p38 MAP kinase. 1229 96

Three new boron compounds, dihydroxy (oxybiguanido) boron (iii) hydrochloride monohydrate (HB), guanidine biboric acid adduct (GB) and hydroxosalicyl hydroxomato boron (iii) (SHB) were studied to observe their antineoplastic effect, if any. Leukemic cells isolated from acute lymphatic leukaemia (ALL) patients and chronic myeloid leukaemia patients (CML) and myeloid leukemia cell lines (HL 60 and U-937) showed cell growth inhibition after treatment with the boron compounds. MTT assay showed that the growth of metabolically active cells was inhibited by treatment with these drugs. The molecular mechanism by which SHB induced apoptosis in immature blast cells was also investigated by ladder formation in gel electrophoresis.
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PMID:Antineoplastic effect of new boron compounds against leukemic cell lines and cells from leukemic patients. 1238 77

Vascular endothelial growth factor (VEGF) is a specific mitogen for vascular endothelial cells. It has been associated with angiogenesis, growth, metastasis and poor prognosis in solid tumors. Lately, it has been known that VEGF expression is higher in bone marrow from chronic myeloid leukemia (CML) patients than that in normal subjects. However, it is not clarified that the effect of VEGF on the abnormal proliferation of CML cells. In order to explore the effect of autocrine VEGF on CML cells, K562 cells were transfected with the VEGF(121) cDNA sense vector (K562/S) or with the VEGF(121) cDNA antisense vector (K562/As). K562 cells were transfected with the pcDNA(3) vector (K562/V) as the control. Cell proliferation was determined by MTT and colony forming assay in vitro. Flow cytometric Annexin-V-FITC/PI dual labeling technique was performed to observe the effect of VEGF(121) cDNA transfection on apoptosis of K562 cells. Results indicated that K562/S transfectants exhibited a 3-fold increase in VEGF secretion, and K562/As transfectants exhibited a 49% reduction in VEGF secretion. K562/As showed a reduced growth rate and colony forming efficiency as compared to K562/V. K562/S showed an increasing growth rate and colony forming efficiency as compared to K562/V. K562/As had more apoptotic cells than K562/V and K562/S in the same culture condition. These data suggest that VEGF plays an important role in the abnormal proliferation and apoptosis in CML cells through an autocrine mechanism.
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PMID:[Effect of Autocrine VEGF on Chronic Myeloid Leukemia Cell Line K562] 1257 89

The purpose of this study was to investigate the function of dendritic cells derived from chronic myeloid leukemia (CML-DC). Mononuclear cells were prepared from bone marrow and peripheral blood of 24 patients with CML, and the DCs were obtained by incubation of MNCs with media containing GM-CSF, IL-4 and TNF-alpha. The phenotype of CML-DCs was identified by flow cytometry. FITC-dextran uptake, (3)H-TdR incorporation or MTT assay and lactate dehydrogenase release assay were used to detect uptake of exogenous antigen in immature DCs, the antigen presenting ability in mature DCs and specific cytotoxicity of CTL to leukemic cells, respectively. The DCs with high expression of CD1a, CD86, CD80, HLA-DR, CD54 and CD4 were obtained from marrow and blood of patients with CML. The uptake of FITC-DX was observed in early DCs. There was a potent stimulation to allo-MLR in DCs cultured for 7 - 10 days, and a lightly lower stimulation to auto-MLR. CML-DCs can induce the generation of specific cytotoxic T cells. These results suggest that CML-DCs are functional DCs with the ability to induce anti-leukemia effect.
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PMID:[The Function of Dendritic Cells Derived from Chronic Myeloid Leukemia] 1257 75

The anticancer effect of black tea (BT) and its polyphenols theaflavin (TF) and thearubigin (TR) has been evaluated on U-937 cell line, a myeloid leukemic cell line and on leukemic cells isolated from peripheral blood of chronic myeloid leukemia (CML) patients. In both types of cells, cell growth inhibition was observed 24 hrs after treatment with BT, TF and TR. MTT assay showed growth inhibition of metabolically active cells and inhibition of DNA synthesis was observed by 3H-Thymidine incorporation after treatment with the compounds. In all cases TF and TR were more effective than BT, suggesting that these are possibly the active components in BT responsible for its antileukemic activity. Superoxide dismutase (SOD), a free radical scavenger, was found to be increased by TF, whereas BT and TR lowered the level in comparison to the control. The present study is the first report of antileukemic effect of BT and its polyphenols.
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PMID:Studies with black tea and its constituents on leukemic cells and cell lines. 1263 3

Bcr-abl antisense oligodeoxynucleotides (AS-ODNs) have provided evidence of an antileukemia effect when tested in vitro against Philadelphia-positive cells. In order to investigate the efficacy of AS-ODNs as purging agents in chronic myeloid leukemia (CML) patients, K562 cells, a human CML cell line, were treated in vitro with various types of AS-ODNs and interferon-alpha. Cells were treated in vitro for 0 and 36 hr with 40 microgram/mL of AS-ODNs, respectively, and incubated at 37 degrees C for 36 hr. Cytotoxic effects were measured by counting the number of viable cells as well as by MTT test. Clonogenic activities were evaluated by methylcellulose culture for 2 weeks. The effects of purging agents on the rearrangement of bcrabl gene were evaluated by RT-PCR. AS-ODNs inhibited the proliferation of K562 cells with time in cell count assay and MTT test. AS-ODNs were superior to INF-alpha in inhibiting clonogenic activity (recovery rate; 26.3% vs 64.0%). After incubation with bcr-abl AS-ODNs primers and mRNA isolated from K562 cells, positive bands were abolished, especially of b3a2 type and phosphorothioate type. Our results suggest that AS-ODNs mediated purging may be one of the efficient methods and that autograft may be an alternative treatment for allograft in high-risk group patients of CML if they do not have a stem cell donor.
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PMID:Myeloablative treatment supported by autologous stem cell infusion with neuroblastoma. 1269 14


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