Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023467 (acute myeloid leukemia)
 35,200 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Fifty-three patients with standard risk leukemia who underwent allogeneic peripheral blood stem cell transplantation (alloPBSCT) from their HLA-identical siblings were analyzed for engraftment, incidence and severity of GVHD, and relapse rate. Standard risk leukemia was defined as AML in first complete remission or CML in first chronic phase within the first year after diagnosis. The median age was 34.5 years (range 13-47). Stem cells were mobilized by using 10 microg/kg G-CSF subcutaneously for 5 days. A median of 5. 7 (2.1-21.4) x 106/kg CD34+ cells was collected over a median of 2 (range 1-5) apheresis procedures. Cyclosporin A (CsA) plus short-course MTX were used for GVHD prophylaxis. Recovery to granulocytes >0.5 x 109/l and platelets >20 x 109/l occurred at a median of day +13 (range 8-32) and +13 (range 8-51), respectively. Day +100 transplant-related mortality was 13.2% (7/53). Acute GVHD occurred in 20 of 49 (41%) evaluable patients and only six (12.3%) of them had severe disease (grade III-IV). Chronic GVHD occurred in 30 of 42 (71.4%) evaluable patients. Relapse rate at 2 years was 7. 5%. The median overall and leukemia-free survivals were 22 (4-44) and 20 (3-44) months, respectively. Estimated 4 year leukemia-free and overall survival rates were 60% and 62%, respectively. In conclusion, alloPBSCT in standard risk leukemia seems to be associated with a low relapse rate and no increased risk of acute GVHD, but there is a trend for higher incidence of cGVHD. Bone Marrow Transplantation (2000) 25, 1229-1232.
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PMID:Allogeneic peripheral blood stem cell transplantation for standard risk leukemia: experience of Ibni Sina Hospital. 1087 26

Drug resistance of leukemic blasts is correlated to event-free survival and might be predicted by mRNA expression of drug resistance-related proteins. Methotrexate (MTX) is an important component in the treatment of childhood leukemia. Mechanisms of MTX resistance include (1) decreased transport via the reduced folate carrier (RFC), (2) altered levels of target enzymes, eg dihydrofolate reductase (DHFR) and thymidylate synthase (TS), (3) decreased ratio of folylpolyglutamate synthetase (FPGS)/folylpolyglutamate hydrolase (FPGH). We designed competitive templates for each of these genes to measure mRNA expression by quantitative RT-PCR and normalized the expression to that of beta-actin. T-lineage acute lymphoblastic leukemia (T-ALL), relatively MTX resistant compared to common/preB-ALL, displayed higher mRNA levels of DHFR and TS (three- and four-fold higher, respectively; P < 0.001), while FPGS expression was lower (three-fold, P = 0.006) compared to common/preB-ALL. The ratio of (DHFR x FPGH)/(RFC x FPGS) was more discriminating between T-ALL and c/preB-ALL (eight-fold higher; P < 0.001) than either target independently. Acute myeloid leukemia (AML) cells, considered MTX resistant, expressed two-fold lower levels of FPGS mRNA compared to c/preB-ALL (P = 0.04). The ratio of FPGH/FPGS was more discriminating between AML and c/preB-ALL (four-fold higher; P = 0.001) than either target independently. For the total group of 79 leukemic samples, mRNA expression of DHFR varied 549-fold and paralleled TS mRNA expression (r = 0.80; P < 0.001). Although variations in mRNA expression resembled variations in functional activity, no direct correlations were found for RFC (58-fold variation in mRNA expression), FPGS (95-fold) and FPGH (178-fold). In conclusion, differences in mRNA expression of MTX resistance parameters between leukemic subtypes as detected by competitive RT-PCR are in line with known differences in MTX resistance.
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PMID:mRNA expression levels of methotrexate resistance-related proteins in childhood leukemia as determined by a standardized competitive template-based RT-PCR method. 1118 7

Methotrexate is in widespread use as second-line therapy for rheumatoid arthritis. Treatment with methotrexate in this and other settings has not been associated with the development of therapy-related leukemias. Four patients with rheumatoid arthritis are reported who developed acute myeloid leukemia (AML) while receiving low dose weekly methotrexate therapy in the absence of previous or concomitant treatment with known leukemogenic agents. AML in these four patients was of different morphologic subtypes and was associated with heterogeneous cytogenetic abnormalities, cell surface marker expression and multidrug resistance protein expression. None of the recognized features of therapy-related leukemia were present in these four nor in five previously-reported patients. It is likely that the occurrence of AML in patients with rheumatoid arthritis in the setting of methotrexate therapy represents the coincidence of these two diseases, and does not reflect a causal relationship.
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PMID:Acute myeloid leukemia in the setting of low dose weekly methotrexate therapy for rheumatoid arthritis. 1169 1

Methotrexate is an important cytostatic drug in therapy of acute lymphoblastic leukemia. Cellular resistance to methotrexate might cause treatment failure. Possible mechanisms of resistance to methotrexate include: decreased accumulation and retention, decreased intracellular polyglutamylation, increased level or mutations of target enzymes, resistance to apoptosis. The literature review shows that resistance to methotrexate might be circumvented by continuous drug infusion in T-ALL, relapsed ALL and in AML. Another possibility to overcome mechanisms of resistance is the use of rationally designed new antifolates, which: can bypass RFC-mediated drug transport, are not dependent on polyglutamylation, have an improved affinity to target enzymes and target also other enzymes.
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PMID:[Methotrexate resistance in acute leukemias]. 1175 24

A 29-year-old male was diagnosed as having non-Hodgkin's lymphoma (NHL, diffuse, large cell, B-cell, stage IV) in June 1999. He underwent 7 courses of chemotherapy and double autologous peripheral stem cell transplantation (total dose: CPA 13,000 mg, BUS 892 mg, L-PAM 150 mg, MCNU 870 mg, MTX 60 mg, Ara-C 160 mg, DXR 350 mg, VP-16 11,190 mg, VCR 8 mg, CBDCA 700 mg, and MIT 22 mg) for NHL and obtained complete remission in April 2000. In September 2000, he suffered from progressive general malaise. Laboratory findings showed marked leukocytosis with 85% leukemia cells, which were positive for alpha-naphthyl butyrate esterase. Surface-marker analysis of the leukemia cells showed positive results for CD11b, CD11c, CD13, CD15, CD33, CD56, CD64, CD65, CD71 and HLA-DR, and chromosomal analysis revealed add(8) (p11), add(9) (p13). He was diagnosed as having AML (M5a) and was still in complete remission for NHL. He did not respond to chemotherapy and died in December 2000, believed to be from therapy-related leukemia induced by the VP-16 used for treating NHL, judging by the patient's short clinical course and monocytic type of leukemia.
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PMID:[Therapy-related acute myeloid leukemia following double autologous peripheral blood stem cell transplantation for non-Hodgkin's lymphoma]. 1213 6

Acute leukemia is the most common form of childhood cancer and is the primary cause of cancer-related mortality in children. In the United approximately 3250 cases are diagnosed annually in children and adolescents younger than 20 years, of whom 2400 have acute lymphoblastic leukemia (ALL). Treatment results in childhood ALL continue to improve, and the expected current cure rates approach 75 to 80% of all children with ALL, including T-ALL and mature B-cell ALL, the two variants that, not too long ago, had a considerably poorer prognosis compared with the common form of BpALL. The most significant new development in the past 2 years has been the development of further evidence for fetal origin of childhood leukemias, and additional evidence to support the notion that postnatal events modulating the events of immune-mediated elimination of these leukemic clones play a major role in the eventual development of clinical disease. Other epidemiologic developments include (1) increased appreciation of the role of drug-metabolizing enzymes, both in determining the predisposition to leukemia and response to therapy; and (2) both clinical observations and gene expression studies seeming to identify a new approach to the evaluation and treatment of children with MLL (11q23) rearrangements. A most remarkable new development in the induction therapy of childhood leukemia and lymphoma in the United States is the use of urate oxidase for prevention of tumor lysis syndrome and the associated uric acid nephropathy. Drug resistance, determined either on leukemic blast cells in vitro or by studies of MRD, is being looked at critically in an effort to improve the treatment results further. Consolidation with HDMTX has gained wider popularity with the realization that effective CNS prophylaxis can be achieved with intrathecal therapy plus HDMTX for consolidation. In contrast to ALL, the progress in the therapy of acute myeloid leukemia (AML) lags behind, with cure rates of approximately 40 to 50%. There is no convincing evidence for substitution of daunorubicin with other anthracyclines, nor evidence for using high-dose cytarabine during induction in childhood AML. Rather, a 3 + 10 regimen with total daunorubicin 180 mg/m2 and cytarabine 100 to 200 mg/2 for 10 days appears to yield the best results. The most important component of the postremission chemotherapy continues to be several courses of high-dose cytarabine. The results from the MRC 10, LAME 89/91 studies and the recent BFM 93 trial with high-dose cytarabine and mitoxantrone suggest that there may be some benefit to including this combination in the postremission phase of AML. Despite these improvements in chemotherapy, allogeneic BMT from a matched family donor remains the best option for most patients (excluding Down syndrome, APL, and possibly those with inv16). Newer prognostic markers of interest include FLT3/ITD and minimal residual disease at the end of induction therapy.
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PMID:Recent advances in pediatric acute lymphoblastic and myeloid leukemia. 1249 Jul 58

Seventeen patients and their family donors HLA 2 - 3 antigen mismatched of 2 - 3 loci were enrolled in the study of haploidentical transplants from February 1999 to March 2001. Among patients with leukemia, most patients were classified as high risk. Eleven patients with ALL were all in more than second remission but one was in relapse. Patients with AML were one in CR1, one in CR2 while 4 patients with CML were two in CP and two in AP. The male-to-female ratio was 14:3 and the median age was 15 (range from 8 to 35). Conditioning regimens included Ara-C 3.0 g/m(2), 2 times per day x 3 d, on day 7, 6 and 5 pre-transplantation, CTX 45 mg/(kg per d) x 2 d on day 5 and 4 pretransplantation. TBI with 1000 cGy by 2 fractions on day 2 and 1 pretransplantation. The fresh and unmanipulated marrow was infused on day 0. Donors were received G-CSF (Lenograstim) at 3 - 4 microg/(kg per d) x 7 d. The BM cells were collected on eighth day. In GVHD prophylaxis, CSA, MTX, ATG (Antithymocyte globulin, Rabbit Fresenius S) and MMF (mycophenolate mofetic) were used in different periods. The dose of CSA was 1.5 mg/(kg per d) on day 7 to 1 pretransplantation, then 3 mg/(kg per d) from day 1 pretransplantation. MTX was 15 mg/m(2) on day 1 and 10 mg/m(2) on day 3, 6 and 11 posttransplantation. ATG was administered day 4 to 1 pretransplantation at 5 mg/(kg per d) and MMF dose was 1.0 g/d from day 7 posttransplantation. All patients established successful engraftment after initial transplantation. The median days of neutrophil exceeding 0.5 x 10(9)/L and platelet exceeding 20 x 10(9)/L were 18 (range 13 - 23) and 20 (range 16 - 32) days, respectively. Patients were monitored up to day 100 for the sign of aGVHD. The established grades II to IV aGVHD occurred in 5 out of 17 patients (29.4%). Eleven patients were surviving at a median follow-up of 13 months (range 3 - 27 months). Six out of the 17 patients died those 3 of them died of severe aGVHD, 2 of infection and 1 of leukemia relapse. Severe regimen-related toxicities were not experienced in all patients. The median follow-up period was 13 (range 3 - 27) months. Eleven patients were alive in disease-free situation with a Karnofsky performance status of 100%. This could be caused by the low overall incidence of aGVHD as a result of BM primed with G-CSF. The four-agent of immunosuppressive combined prophylaxis against GVHD in different periods may be highly effective.
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PMID:[Successful engraftment of T-cell undepleted haploidentical transplants by donor primed with G-CSF and additional use of ATG and MMF for recipients]. 1251 19

The fluorescence signal intensity of the DHFR gene was analysed in lymphocytes from 15 normal donors, in MTX-resistant HeLa cells (carrying DHFR gene amplification) and in bone marrow blasts from 16 patients with acute leukaemia (AL) by in situ hybridisation. Our aim was to verify if DHFR gene amplification may be responsible for increased enzyme activity in leukemic cells. The results obtained with a fluorescence in situ hybridisation method were quantified using the Scion image software program and compared with cytochemical and cytophotometric data relating to DHFR activity. In AL a heterogeneous hybridisation pattern was generally observed at the single cell level. However, leukemic lymphoblasts showed higher fluorescence signal intensity of the DHFR gene as compared with normal lymphocytes, and leukemic myeloblasts a much higher signal than lymphoblasts. HeLa cells showed the highest fluorescence signal intensity. In all samples enzyme activity behaved in parallel. These results indicate that the increased expression of DHFR in leukemic blasts is due to a gene amplification. The high levels in AML can explain the MTX natural resistance.
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PMID:Quantification of the DHFR gene in blast cells of leukaemia patients by fluorescence in situ hybridisation. 1466 92

In Children's Cancer Group (CCG) study 2891, patients who were recently diagnosed with acute myelocytic leukemia (AML) were assigned randomly to standard- or intensive-timing induction chemotherapy. Patients in first complete remission (CR1) and who had a human leukocyte antigen (HLA)-identical, related donor or a donor disparate at a single class I or II locus were nonrandomly assigned to receive a bone marrow transplant (BMT) by using oral busulfan (16 mg/kg) and cyclophosphamide (200 mg/kg). Methotrexate only was given for graft-versus-host disease (GVHD) prophylaxis. One hundred fifty patients received transplants. Grade 3 or 4 acute GVHD occurred in 9% of patients. Patients younger than 10 years had a lower incidence of grade 3 or 4 GVHD (4.6%) compared with patients 10 years or older (17.4%) (P =.044). Disease-free survival (DFS) at 6 years was 67% and 42% for recipients of intensive- and standard-timing induction therapies, respectively. Multivariate analysis showed that receiving intensive-timing induction therapy (P =.027) and having no hepatomegaly at diagnosis (P =.009) was associated with favorable DFS, and grades 3 and 4 acute GVHD were associated with inferior DFS. Multivariate analysis showed that grades 1 or 2 GVHD (P =.008) and no hepatomegaly at diagnosis (P =.014) were associated with improved relapse-free survival (RFS). Our results show that children older than 10 years are at higher risk for developing severe GVHD; acute GVHD is associated with favorable RFS.
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PMID:Allogeneic bone marrow transplantation for children with acute myelocytic leukemia in first remission demonstrates a role for graft versus leukemia in the maintenance of disease-free survival. 1475 24

The combination of Cyclosporin A (CSA) and Methotrexate (MTX) is considered to be the standard regimen for the prevention of graft-versus-host disease (GVHD) after stem cell transplantation (SCT) from HLA-identical siblings. Mycophenolate Mofetil (MMF) has been widely used for GVHD prophylaxis after nonmyeloablative SCT, but experience following myeloablative therapy is still limited. We retrospectively compared CSA/MTX and CSA/MMF in 93 patients (median age 35 years, range 17-59 years, male subjects 48, female subjects 45) with acute myeloid leukemia (n=33), myelodysplastic syndrome (MDS) (n=3), acute lymphoblastic leukemia (ALL) (n=20) or chronic myeloid leukemia (n=37) who received CSA/MMF (n=26) or CSA/MTX (n=67) as GVHD prophylaxis following high-dose therapy and allogeneic SCT from HLA-identical siblings. No statistically significant differences were found in overall survival, relapse rate, treatment-related mortality and acute or chronic GVHD. Time to myeloid recovery was significantly shorter in patients who received CSA/MMF. We conclude that the combination of CSA/MMF appears equivalent to CSA/MTX for GVHD prophylaxis in patients receiving conventional-intensity SCT from HLA-identical siblings.
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PMID:Cyclosporine A and mycophenolate mofetil vs cyclosporine A and methotrexate for graft-versus-host disease prophylaxis after stem cell transplantation from HLA-identical siblings. 1628 7


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