Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hematopoetic stem cell transplantation (SCT) often represents a unique opportunity for curing children with leukemia. Nevertheless, selecting the patient who could really benefit from this procedure remains a controversial issue. The current consensus is as follows: About 20% of children with ALL can be defined as high-risk patients by criteria such as t(9;22), t(4;11), no complete remission at day 42, poor prednisone response, and T-immunophenotype or pre-pre B-ALL, myeloid markers or more than 100,000 white blood cells/microliter. This high-risk group is eligible for alloBMT in first remission, provided a family-matched donor is available. At relapse the majority of patients will benefit from alloBMT, and alternative donor sources can be considered in high-risk patients. Only early alloBMT relapses (up to 6 months after end of initial therapy) are sure candidates, whereas late relapses, especially extramedullary sites, may equally benefit from an intensive conventional relapse treatment. However, any alloBMT relapse beyond second remission should be transplanted with allogeneic stem cells (bone marrow or peripheral stem cells). In particular, family mismatched donors or matched unrelated donors may be acceptable in high-risk cases beyond first remission. In contrast, ASCR in ALL seems not to be superior to conventional therapy. In AML the standard-risk patient, defined by criteria such as FAB M1/M2-Auer rods positive, all FAB M3, and FAB M4, is not a candidate for SCT in first remission. Patients presenting other criteria or more than 5% of blasts in the bone marrow at day 15 are at high risk in first remission and should be considered for allo BMT if a family matched donor is available. ASCR in first remission AML remains a controversial issue. In contrast, in second remission alloBMT as well as ASCR are superior to conventional chemotherapy.
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PMID:The present role of bone marrow and stem cell transplantation in the therapy of children with acute leukemia. 938 54

Chemically-induced rodent tumor models help us to understand a series of genetic changes during carcinogenesis. In this study, we present N-nitroso-N-butylurea (NBU)-induced rat leukemia and compare it with the genetic alterations found in 7,12-dimethylbenz[a]anthracene (DMBA)-induced erythroblastic leukemias which consistently have an A to T transversion at the second base of codon 61 in N-ras. By continuous NBU treatment for 120-150 days, 14 primary leukemias were induced in Long-Evans rats. Myeloblastic leukemia cells predominantly increased in all rats except in one case which predominantly had erythroblastic leukemia cells. Point mutations of Ha-, Ki-, N-ras and p53 were determined after RNA was transcribed into cDNA and this cDNA was used as a substrate for polymerase chain reaction (PCR) which was eventually sequenced. No abnormalities in exons 1 and 2 of Ha-, Ki- and N-ras were detected in all leukemias. In the p53 gene, an A to C transition was found at the second base of codon 198 (Asn-Thr) in one leukemia, but others had no mutation. These results suggest that ras and p53 genes are infrequently involved in NBU-induced leukemias. The genetic target of NBU during leukemogenesis seemed to be different from that of DMBA.
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PMID:ras and p53 genes are infrequently involved in N-nitroso-N-butylurea (NBU)-induced rat leukemia. 950 Feb 11

11q23 translocations (t(11q23)) are recurring cytogenetic abnormalities in both acute myeloid leukemia (AML) and acute lymphoblastic leukemia, involving the same gene, ALL1 (or MLL). Mixed lineage antigen expression has been reported in these leukemias, but its frequency and clinical significance are unknown. We immunophenotyped leukemia cells from 19 adult de novo AML patients with t(11q23) by multiparameter flow cytometry. Translocations included t(6;11)(q27;q23), t(9;11)(p22;q23), t(9;11;19)(p22;q23;q13.3), t(2;11)(11;17)(q37;q11q23;q11), t(11;17)(q23;q25), t(11;19)(q23;p13.1), t(11;19)(q23;p13.3) and t(11;22)(q23;q11). FAB types were M4 and M5. The committed stem cell and myeloid antigens HLADr, CD4dim, CD11b, CD13, CD15, CD32, CD33, CD38 and CD64 were each expressed in 80-100% of cases, and the early stem cell and lymphoid antigens CD34, CD56, CD3, CD2 and CD7 in 42, 39, 16, 5 and 5%, respectively. Antigen expression frequencies did not differ from those in 443 adequately karyotyped M4 and M5 cases without t(11q23). Fifteen patients (79%) attained complete remission (CR); median CR duration and survival were 10.0 and 15.1 months. CR duration and survival did not correlate with antigen expression. In particular, patients with t(9;11) survived longer than those with other t(11q23) (median not reached vs 7.6 months; P = 0.048), but antigen expression did not differ in the two groups. Thus frequencies of lymphoid antigen expression are similar in AML with t(11q23) and in other FAB M4 and M5 cases, treatment outcome does not differ in t(11q23) cases with and without lymphoid antigen expression, and better outcome of patients with t(9;11) compared to other t(11q23) does not correlate with differences in antigen expression. Mixed lineage antigen expression is not a distinctive feature of AML with t(11q23).
Leukemia 1998 Mar
PMID:Acute myeloid leukemia with 11q23 translocations: myelomonocytic immunophenotype by multiparameter flow cytometry. 952 25

HOX genes have shown a lineage-specific expression in hematopoiesis and are suggested as being involved in the expression of certain adhesion molecules. Recently, we have demonstrated that HOXC4 and HOXC6, but not HOXC5, are expressed during lymphoid differentiation. Reports on the expression of these genes in myeloid leukemias and normal myeloid cells are still scarce. Therefore, we have investigated the expression of HOXC4, HOXC5 and HOXC6 in purified subpopulations of bone marrow in addition to 36 specimens of acute myeloid leukemias (AMLs), eight chronic myeloid leukemias (CMLs), several myeloid cell lines and cutaneous localizations of three myelomonocytic leukemias and one granulocytic sarcoma by RT-PCR and partly by RNA in situ hybridization (RISH). HOXC4 and HOXC6 transcripts were both detected by RT-PCR in 22/36 and 24/36 AMLs, respectively. The distribution of HOXC4 and HOXC6 gene expression over the different types of AML was largely similar and covered all types of AML. In contrast, HOXC5 gene expression was found in only 6/32 AMLs. Expression of HOXC5 was restricted to AMLs of the granulocytic (FAB M1-M3), early monocytic (FAB M4) and early erythroid (FAB M6) lineage. In general, except in one FAB M5b case, no expression of HOXC5 was found in AMLs derived from late stages of monocytic (FAB M5) and megakaryocytic (FAB M7) lineages. As for HOXC4 and HOXC6, expression of HOXC5 was absent in CMLs. Using RISH significant HOXC4, HOXC5 and HOXC6 expression was found in a number of additionally studied AML samples of different FAB classification (M2, M4, M5b and M5b), (M2 and M5b) (M2, M4, M5b), respectively. In tissue localizations of leukemias a different expression pattern of HOXC4, HOXC5 and HOXC6 was found. In contrast to mature leukemic stages of myeloid differentiation, these skin localizations of leukemias expressed HOXC5 and HOXC6. HOXC4 expression was found both in leukemic cells derived from peripheral blood and from cutaneous localizations. Besides HOXC4 expression in monocytes no expression of HOXC4, HOXC5 and HOXC6 was found in granulocytes and monocytes, colonies of growth factor-induced CD34+ bone marrow cells. In earliest CD34+/CD38low and high cell fractions of bone marrow only HOXC4 and in megakaryocytic cells both HOXC4 and HOXC6 were found. Thus, the expression patterns of these HOXC genes found in the limited number of cell fractions of normal bone marrow suggest that the expression patterns found in AMLs and CMLs might reflect the normal situation. Furthermore, the presence of HOXC5 and HOXC6 expression specifically in skin infiltrates of late differentiation stages of myeloid leukemias, suggests an additional role for these genes in the positioning of these myeloid cells in skin tissue.
Leukemia 1998 Nov
PMID:Differentiation and cell-type-restricted expression of HOXC4, HOXC5 and HOXC6 in myeloid leukemias and normal myeloid cells. 982 47

A 19-year-old male patient with virus associated hemophagocytic syndrome (VAHS) began receiving chemotherapy including etoposide (cumulative dose of 900 mg/m2 intravenously) and Ara-C (cumulative dose of 360 mg/m2 intravenously) in July 1994. He achieved complete remission, but developed acute myelomonocytic leukemia (AML, FAB M4) with t(9;11)(p22;q23) in March 1997 and a rearrangement of the MLL gene was also recognized. The MLL gene rearrangement is closely associated with secondary leukemia with an 11q23 translocation. It is highly likely that this case of AML was caused by the cytostatic treatment the patient received, including etoposide for VAHS.
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PMID:Therapy-related AML after successful chemotherapy with low dose etoposide for virus-associated hemophagocytic syndrome. 984 19

Myelodysplastic syndrome is a closely related group of acquired bone marrow disorders characterized by ineffective and dysplastic hematopoiesis. These clonal disorders frequently progress to acute leukemia. Acute myelomonocytic leukemia with eosinophilia is characterized by an increase in abnormal eosinophils in the bone marrow, relatively good clinical course and inv (16) chromosomal abnormality. We experienced one case of refractory anemia with excess blasts which progressed to refractory anemia with excess blasts in transformation and finally to acute myelomonocytic leukemia with eosinophilia showing peculiar chromosomal abnormalities of der (1;7).
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PMID:Myelodysplastic syndrome that progressed to acute myelomonocytic leukemia with eosinophilia showing peculiar chromosomal abnormality: a case report. 1048 27

Chromosomal translocations are frequently linked to multiple hematological malignancies. The study of the resulting abnormal gene products has led to fundamental advances in the understanding of cancer biology. This is the first report of t(2;15)(p23;q22) and t(2;17)(p23;q21) translocations in human malignancy. Patient 1, a 73-year-old male, was diagnosed with myeloblastic (FAB M1 sub-type) AML. Cytogenetic analysis showed a 47,XY,t(2;15)(p23;q22),+13 karyotype. Fluorescent in situ hybridization (FISH) showed that the PML gene was transferred intact to the short arm of chromosome 2 while the ALK gene on chromosome 2p23 was passively transferred to the long arm of chromosome 15. Patient 2 was a 60-year-old male diagnosed with monocytic (FAB M4-type) AML. Cytogenetic analysis showed 46,XY,t(2;17)(p23;q21) karyotype. FISH analysis showed that neither RARalpha nor ALK were disrupted by the translocation. None of the coding region of the three genes studied were translocated in these patients. This raises the possibilities that other neighboring genes could be involved or that noncoding regulatory sequences of the studied genes could be put in contact and deregulate expression of other genes. Alternatively, displacement of ALK, RARalpha and PML to novel positions could lead to loss of their normal regulation
Leukemia 1999 Oct
PMID:Identification of novel chromosomal rearrangements in acute myelogenous leukemia involving loci on chromosome 2p23, 15q22 and 17q21. 1051 54

Little is known about the factors that affect treatment outcome in very young children with acute myeloid leukemia (AML). We therefore analyzed the prognostic impact of various presenting clinical and laboratory features by discrete age group in 299 children with AML treated in four consecutive clinical trials between 1980 and 1997. Differences in presenting features, as well as treatment outcome, were compared between children aged 12 months or less (n = 28) or 13 to 24 months (n = 28) and those more than 24 months of age (n = 243). Children in the two youngest groups (24 months of age or less) had similar presenting features and treatment outcome. Collectively, these 56 children were significantly more likely than the 243 older patients to have M4 or M5 leukemia (70% vs 30%), CNS leukemia (33% vs 22%), the t(9;11) (p22;q23) (18% vs 6%) or other 11q23 translocations (23% vs 3%), and less likely to have Auer rods (2% vs 54%) or the t(8;21) (q22;q22) (0% vs 17%). Among patients aged 24 months or less, two factors independently predicted a favorable prognosis: FAB M4 or M5 leukemia (relative risk of relapse, 0.4; 95% confidence interval, 0.2-0.9) and the t(9;11) (relative risk, 0.3; 95% confidence interval, 0.1-1.0). Leukocyte count and 11q23 translocations other than the t(9;11) lacked prognostic significance. Among older patients, a leukocyte count <50 x 10(9)/l and the presence of the t(9;11) conferred a favorable prognosis.
Leukemia 2000 Apr
PMID:Prognostic factors in infants with acute myeloid leukemia. 1076 55

A patient with relapsed acute myelomonocytic leukemia (AML, FAB M4) developed skin infiltration by leukemic blasts. On immunochemistry, the blasts showed "bot" positive cytoplasmic staining for cytokeratins AE1/AE3 and CAM 5.2, resembling the pattern seen in Merkel cell carcinoma of skin. However, the blasts were positive for myeloid markers and negative for cytokeratin 19 and chromogranin. Aberrant immunochemical staining can lead to misdiagnosis unless a panel of antibodies of known specificity is used in tumor diagnosis, and the clinical context is taken into account. The possible role of cytokeratin 19 as a more specific marker for epithelia than keratin cocktails is discussed.
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PMID:A case of keratin-positive acute myeloid leukemia: a possible role for cytokeratin 19 as a specific epithelial marker. 1084 Aug 28

Determining in vitro drug resistance may reveal clinically relevant information in childhood leukemia. Using the methyl-thiazol-tetrazolium assay, the resistance of untreated leukemic cells to 21 drugs was compared in 128 children with acute myeloid leukemia (AML) and 536 children with acute lymphoblastic leukemia (ALL). The differences between 3 French-American-British (FAB) types (M1/M2, M4, and M5) were also compared. AML was significantly more resistant than ALL to the following drugs, as noted by the median resistance: glucocorticoids (greater than 85-fold), vincristine (4.4-fold), L-asparaginase (6.9-fold), anthracyclines (1.8- to 3.4-fold), mitoxantrone (2.6-fold), etoposide (4.9-fold), platinum analogues (2.4- to 3.4-fold), ifosfamide (3.5-fold), and thiotepa (3.9-fold). For cytarabine and thiopurines, the median LC50 values (the drug concentration that kills 5% of the cells) were equal. Also, busulfan, amsacrine, teniposide, and vindesine showed no significant differences, but the numbers were smaller, and the median LC50 values were 1.3- to 5.2-fold higher in AML. None of the drugs demonstrated greater cytotoxicity in AML. FAB M5 was significantly more sensitive than FAB M4 to most drugs frequently used in AML, as indicated by the following ratios of median sensitivities: the anthracyclines (2.6- to 3.2-fold), mitoxantrone (12.5-fold), etoposide (8.7-fold), and cytarabine (2.9-fold). For etoposide and cytarabine (5.4- and 3.4-fold, respectively) FAB M5 was also significantly more sensitive than FAB M1/M2. FAB M5 was equally sensitive to L-asparaginase and vincristine as ALL. Only 15% of the AML samples were "intermediately" sensitive to glucocorticoids, mainly in FAB M1/M2. The poorer prognosis of childhood AML is related to resistance to a large number of drugs. Within AML, FAB M5 had a distinct resistance pattern. These resistance profiles may be helpful in the rational design of further treatment protocols. (Blood. 2000;96:2879-2886)
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PMID:Cellular drug resistance profiles in childhood acute myeloid leukemia: differences between FAB types and comparison with acute lymphoblastic leukemia. 1102 25


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