Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0432222 (SEM)
 47,337 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Severe infections are a major problem in patients suffering from acute nonlymphocytic leukemia (ANLL) undergoing myeloablative chemotherapy. Possible factors leading to infectious complications in these patients are suppressed immune defense mechanisms existing prior to therapy, including those involving the neutrophil granulocyte department. In this study we investigated whether neutrophil function as measured by oxidative burst and phagocytosis before the start of treatment correlates with the severity of infection after therapy. Forty-four patients were included, 27 men and 17 women. Their median age was 46 years (range 20-70 years). According to the development of infectious complications the patients were assigned retrospectively to group 1 (no or only mild infections, n = 29) or to group 2 (severe infection or death due to infection, n = 15). The phagocytic activity was significantly reduced in group 2 as compared with group 1 [113.7+/-13.7 (SEM) vs 170.0+/-19.2, mean channel fluorescence; p =0.04]. In contrast, the oxidative burst as measured by FMLP stimulation was pronounced but not significantly enhanced in group 2 (24.8+/-6.1 vs 14.5+/-3.4, mean channel fluorescence). In conclusion, patients with severe infections after chemotherapy might already have preactivated neutrophils with suppressed function prior to treatment. Thus, evaluating function parameters could help to estimate the individual risk of infection for a patient with ANLL.
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PMID:Suppressed neutrophil function as a risk factor for severe infection after cytotoxic chemotherapy in patients with acute nonlymphocytic leukemia. 1008 21

In this study, soluble thrombomodulin (TM) was measured as an indicator of endothelial injury in acute myelocytic leukemia (AML) together with fibronectin (FN) and thrombospondin (TS). The study group comprised of 17 (6 men, 11 women; aged 34 +/- 10 years; range 21-61 years) newly diagnosed AML patients. There was infection in 6 patients. Twelve (4 men, 8 women; aged 31 +/- 11 years; range 18-55 years) healthy subjects were studied as the control group. Plasma soluble TM levels were significantly higher in AML patients than in the healthy control group (116.6 +/- 13.7 vs 37.2 +/- 1.75 ng/ml, respectively (mean +/- SEM), p < 0.01). Plasma FN levels were found to be significantly higher in AML patients compared to the control group (15.9 +/- 2.69 vs 8.1 +/- 2.46 ng/ml, respectively (mean +/- SEM). p < 0.01 ). Plasma FN levels in infected patients were significantly lower than in non-infected patients (6.47 +/- 1.3 vs 21.0 +/- 3.1 ng/ml, respectively (mean +/- SD), p < 0.01). Plasma TS levels in the patient group were significantly lower than in the control group (20.6 +/- 1.45 vs 120.8 +/- 18.2 ng/ml, respectively (mean +/- SEM), p < 0.01). In one patient with M7 megakaryoblastic leukemia who also had a high platelet count, plasma TS levels were significantly higher than that in other patients.
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PMID:Circulating thrombomodulin, thrombospondin, and fibronectin in acute myeloblastic leukemias. 1043 67

Delivery of targeted hematopoietic irradiation using radiolabeled monoclonal antibody may improve the outcome of marrow transplantation for advanced acute leukemia by decreasing relapse without increasing toxicity. We conducted a phase I study that examined the biodistribution of (131)I-labeled anti-CD45 antibody and determined the toxicity of escalating doses of targeted radiation combined with 120 mg/kg cyclophosphamide (CY) and 12 Gy total body irradiation (TBI) followed by HLA-matched related allogeneic or autologous transplant. Forty-four patients with advanced acute leukemia or myelodysplasia received a biodistribution dose of 0.5 mg/kg (131)I-BC8 (murine anti-CD45) antibody. The mean +/- SEM estimated radiation absorbed dose (centigray per millicurie of (131)I) delivered to bone marrow and spleen was 6.5 +/- 0.5 and 13.5 +/- 1.3, respectively, with liver, lung, kidney, and total body receiving lower amounts of 2.8 +/- 0.2, 1.8 +/- 0.1, 0.6 +/- 0.04, and 0.4 +/- 0.02, respectively. Thirty-seven patients (84%) had favorable biodistribution of antibody, with a higher estimated radiation absorbed dose to marrow and spleen than to normal organs. Thirty-four patients received a therapeutic dose of (131)I-antibody labeled with 76 to 612 mCi (131)I to deliver estimated radiation absorbed doses to liver (normal organ receiving the highest dose) of 3.5 Gy (level 1) to 12.25 Gy (level 6) in addition to CY and TBI. The maximum tolerated dose was level 5 (delivering 10.5 Gy to liver), with grade III/IV mucositis in 2 of 2 patients treated at level 6. Of 25 treated patients with acute myeloid leukemia (AML)/myelodysplastic syndrome (MDS), 7 survive disease-free 15 to 89 months (median, 65 months) posttransplant. Of 9 treated patients with acute lymphoblastic leukemia (ALL), 3 survive disease-free 19, 54, and 66 months posttransplant. We conclude that (131)I-anti-CD45 antibody can safely deliver substantial supplemental doses of radiation to bone marrow (approximately 24 Gy) and spleen (approximately 50 Gy) when combined with conventional CY/TBI.
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PMID:Phase I study of (131)I-anti-CD45 antibody plus cyclophosphamide and total body irradiation for advanced acute leukemia and myelodysplastic syndrome. 1043 11

In this study, we examined the role of Fas-signaling in the apoptotic pathway in myelodysplastic syndromes (MDS). Ficoll-separated mononuclear cells from 18 bone marrow aspirate specimens obtained from 17 MDS patients, 4 normal healthy donors, and 3 acute myeloid leukemia patients transformed from MDS (t-AML) were studied for mRNA expression of Fas-L, Fas, and the effectors of their signaling, Caspase 1 and Caspase 3, using reverse transcriptase polymerase chain reaction. Fas-L, Fas, and Caspase 1 were detectable in all of the samples in the three groups. Caspase 3 was detectable both in MDS and t-AML specimens but was negligible in normal cells. The apoptotic index (AI%) determined by in situ end labeling of fragmented DNA in 4-hour cultures of mononuclear cells was significantly higher in MDS cells compared to normal or t-AML cells (mean +/- SEM: 2.3% +/- 0.4% in MDS, n = 10 vs. 0.6% +/- 0.2%, n = 4, P = 0.014 in normal cells, and 0.2% +/- 0.2%, n = 3, P = 0.007 in t-AML cells). Treatment of MDS cells with anti-Fas-L antibody suppressed apoptosis (AI%: 2.1% +/- 0.6% in untreated vs. 1.37% +/- 0.5% in treated, n = 6, P = 0.02), indicating functional participation of Fas-signaling in MDS. Further, it was found that Fas-L, Fas, and Caspase 1 mRNA expression remained unchanged in 4 hours. Caspase 3 expression appeared in normal cells after 4 hours and was present at both 0 and 4 hours in MDS and t-AML cells. In contrast to persistent expression in normal and t-AML cells, cells from the 5 MDS patients studied consistently showed significantly lowered or undetectable expression of a negative regulator of Fas, called Fas-associated phosphatase-1 (Fap-1) after 4 hours. Thus, the high AI% in MDS corresponds to a rapid decline in Fap-1. Furthermore, in tumor necrosis factor alpha (TNF-alpha) treated HL60 promyelocytic cells, a definite periodicity in the expression of different mRNAs was observed with upregulation of TNF-alpha itself at 30 minutes, increased expression of Fas and the appearance of Fas-L after 2 hours, and a decrease in Fap-1 expression after 8 hours. These results suggest that TNF-alpha not only induces the effectors of Fas-signaling but also may downregulate the inhibitor. We conclude that a spontaneous and rapid down-regulation of Fap-1, possibly induced by TNF-alpha, a cytokine shown to be present in excess in MDS marrows, may underlie the increased apoptotic death of hematopoietic cells in these patients. Interference with Fap-1 turnover may provide a new therapeutic modality for MDS.
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PMID:Spontaneous down-regulation of Fas-associated phosphatase-1 may contribute to excessive apoptosis in myelodysplastic marrows. 1049 46

Angiogenesis plays a key role in solid tumor growth. The purpose of this work was to study angiogenesis in acute myeloid leukemia (AML). We stained bone marrow samples from 20 adult patients with untreated AML and 20 normal controls using endothelial cell markers (ULEX-E and von Willebrand factor [vWF]). The number of vessels per millimeter length of bone marrow core biopsy specimen was scored by light microscopy. Using ULEX-E staining, AML marrows had (average +/- SEM) 8.3 +/- 3.6 vessels/mm (range, 3.7-19.3), whereas normal marrows had 4.3 +/- 1.8 vessels/mm (range, 1.6-7.9). A similar difference was noted using vWF staining (8.6 +/- 3.0 vessels/mm vs 4. 9 +/- 2.2 vessels/mm in AML vs normal bone marrows, respectively). The differences between the numbers of vessels/mm in AML and normal marrows were highly significant (P <.0001 for both ULEX-E and vWF staining). When analyzed by FAB category, there was no difference in the average number of vessels/mm among the different subgroups of AML. Using reverse transcriptase polymerase chain reaction, we observed that the HL-60 and U937 human AML cell lines and 4 of 4 freshly isolated AML cells from untreated patients expressed mRNA for vascular endothelial growth factor (VEGF). Both cell lines as well as all fresh AML isolates tested expressed VEGF protein. Basic fibroblast growth factor was expressed only in HL-60 cells and in only 3 of 4 fresh AML samples. These observations suggest that angiogenesis may play a role in the pathogenesis of AML. Inhibition of angiogenesis could constitute a novel strategy for the treatment of AML. (Blood. 2000;95:309-313).
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PMID:Evidence of increased angiogenesis in patients with acute myeloid leukemia. 1118 59

In this study, we evaluated the suitability of the calcein assay as a routine clinical laboratory method for the identification of multidrug-resistant phenotype in acute leukaemia. This study presents the results of the calcein tests obtained in two large haematological centres in Hungary. Assays were performed with blast cells of 93 de novo acute leukaemia patients, including 65 patients with acute myeloid leukaemia (AML). Results were expressed as multidrug resistance activity factor (MAF) values. AML patients were divided into responders and non-responders and MAF values were calculated for each group. In both centres, responder patients displayed significantly lower MAF values than non-responders (P = 0.0045 and P = 0.0454). Cut-off values were established between the MAFR + SEM and MAFNR - SEM values. On the basis of these cut-off levels, multidrug resistance (MDR) negativity showed a 72% predictive value for the response to chemotherapy, whereas MDR positivity was found to have an average predictive value of 69% for therapy failure. MDR activity was a prognostic factor for survival rate and the test was suitable for detecting patients at relapse. The calcein assay can be used as a quantitative, standardized, inexpensive screening test in a routine clinical laboratory setting. The assay detects both P-glycoprotein and multidrug resistance-associated protein activities, and identifies AML patients with unfavourable therapy responses.
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PMID:Calcein assay for multidrug resistance reliably predicts therapy response and survival rate in acute myeloid leukaemia. 1116 23

Angiogenesis is of prognostic importance not only in solid tumors but also in malignant blood diseases. We measured levels of vascular endothelial growth factor (VEGF), angiogenin (ANG), and basic fibroblast growth factor (bFGF) in peripheral blood samples from 65 patients with myelodysplastic syndrome (MDS), from 25 patients with de novo acute myeloid leukemia (AML), and from 50 healthy donors. In matched samples, VEGF levels in serum were substantially higher than VEGF levels in plasma (380.7 +/- 56 pg/ml vs. 45.3 +/- 4.5 pg/ml, mean +/- SEM, p < 0.001), whereas serum and plasma levels of ANG were comparable and significantly correlated (r = 0.8; p < 0.01). Compared to normal controls (1.3 +/- 0.09 pg), serum levels of VEGF corrected for the peripheral blood platelet count (VEGF/10(6) platelets, VEGF(PLT)) were elevated in patients with refractory anemia (RA; 3.1 +/- 0.8 pg, p < 0.01), and reached maximal values in patients with advanced stage MDS (RAEB, RAEB-t) (3.5 +/- 0.6 pg, p < 0.001), de novo AML (3.6 +/- 1.1 pg, p < 0.05), and chronic myelomonocytic leukemia (CMML; 3.7 +/- 0.9 pg; p < 0.001). Levels of soluble ANG were elevated in RA (351 +/- 25.7 ng/ml, p < 0.001), in RAEB/RAEB-t (402 +/- 17.9 ng/ml; p < 0.001), in CMML (413.8 +/- 29.5 ng/ml; p < 0.001), and in patients with AML (305.1 +/- 17.1 ng/ml; p < 0.01, controls 255.4 +/- 8.1 ng/ml). Serum bFGF was neither elevated in MDS nor in AML patients. These results suggest that VEGF(PLT) is a marker of disease progression in MDS. Moreover, we show for the first time that elevated blood levels of ANG can be found in patients with myeloid malignancies, suggesting a role of ANG in the pathogenesis of these diseases.
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PMID:Blood levels of angiogenin and vascular endothelial growth factor are elevated in myelodysplastic syndromes and in acute myeloid leukemia. 1184 8

Efflux pumps are considered being mechanisms behind drug resistance in acute myeloid leukaemia (AML). A recently described efflux pump, breast cancer resistance protein (BCRP), can be expressed in AML, but its clinical importance is uncertain. In this study BCRP mRNA expression was determined in samples from 40 AML patients by real-time RT-PCR. The expression varied from negative to 76 times that of control cells. There was no difference in BCRP mRNA expression between patients responding to induction treatment and non-responders. However, in the group of responders, the 14 patients with the highest expression had significantly shorter overall survival (mean 38 months, SEM 15 months) than the 14 patients with the lowest (74 months, SEM 16 months) (P = 0.047). This suggests a possible role of BCRP in drug resistance in AML.
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PMID:BCRP mRNA expression v. clinical outcome in 40 adult AML patients. 1560 61

CXCR4 chemokine receptors retain hematopoietic progenitors and leukemia cells within the marrow microenvironment. We prospectively evaluated the prognostic implication of CXCR4 in 90 consecutive patients with acute myelogenous leukemia (AML) by flow cytometry. Patients were divided into groups with low (n=32), intermediate (n=26), or high (n=32) CXCR4 expression, as defined by CXCR4 mean fluorescence intensity ratio thresholds of less than 5, 5 to 10, or more than 10, respectively. We found that low CXCR4 expression on AML cells correlated with a better prognosis, resulting in a longer relapse-free and overall survival of 24.3+/-2.9 months for low CXCR4-expressing patients, compared with 17.4+/-3.4 months for intermediate and 12.8+/-2 months (mean+/-SEM) for patients with high expression. In univariate analyses, CXCR4 expression, cytogenetics, white blood cell count, and serum lactate dehydrogenase (LDH) predicted for shorter survival. Multivariate analysis revealed CXCR4 expression and unfavorable cytogenetics as independent prognostic factors. We conclude that CXCR4 expression in AML is an independent prognostic predictor for disease relapse and survival that can rapidly and easily be determined at disease presentation. These findings warrant further investigation into the role of CXCR4 in AML and suggest that CXCR4 should be incorporated into the risk assessment of AML patients.
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PMID:CXCR4 is a prognostic marker in acute myelogenous leukemia. 1688 90

Acute myeloid leukaemia (AML) is an aggressive malignancy with accumulation of blasts in bone marrow. Myeloblasts can entry into peripheral blood stream and secondary localize in extramedullary sites. The regulation of this process has not been clearly explained so far, but interactions between some chemokines and their specific receptors could be one of the mechanisms responsible for such kind of migration. Monocyte chemoattractant protein 1 (MCP-1/CCL2) is the chemokine which could be involved in this process. The aim of the study was to evaluate plasma level of CCL2 in patients with AML. Plasma samples from 65 adult patients with AML taken before chemotherapy and in complete remission were measured by enzyme linked immunoassay to evaluate CCL2 levels. Control group consisted of 15 healthy subjects. In AML patients mean baseline CCL2 level (+/- SEM standard error of measurement) was significantly higher than in normal control: 365,26 +/- 5,62 pg/ml vs 265,56 +/- 5,48 pg/ml respectively (p<0.01). We demonstrate increased mean CCL2 plasma level in untreated patients with AML. Significantly lower plasma level of CCL2 was observed in patients with M4 and M5 AML subtypes according to FAB classification. In AML group chemotherapy did not reduce CCL2 plasma level.
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PMID:Increased monocyte chemoattractant protein 1 (MCP-1/CCL-2) serum level in acute myeloid leukemia. 1782 17


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