Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “LEUKEMIA”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 163 records · Page 9Linked to original sources

Inducement of specific CTLs by antigen-peptides from human leukemia cells and their cytotoxicity to leukemia cells.

To investigate the inducement of cytotoxic T lymphocytes (CTLs) by antigen peptides mixture from different leukemia cells and the cross-reaction of the mixtures from different cell lines, antigen peptides mixtures were prepared from different leukemia cell lines respectively and then bound with Hsp70 in vitro. Activation and proliferation of PBMC were observed after stimulation with different Hsp70-peptide complexes. The ratio of CD8+ in proliferative cells was analyzed by flow cytometry. The cytotoxicity of the activated PBMC to different target cells was assayed. The results showed that the antigen peptides from different leukemia cell lines, bound with Hsp70, could activate PBMC effectively, and stimulate the activated PBMC to proliferate. The proliferative PBMC had specific cytotoxicity to corresponding leukemia cells. CD8+ cells, accounting for a high proportion in proliferative cells, had a specific cytotoxicity to leukemia cells from which antigen peptides were prepared, suggesting that these CD8+ cells were CTLs specific to leukemia cells. CTLs activated by Hut78-peptides or Molt4-peptides had a significantly stronger cytotoxicity to Hut78 cells, Molt-1 cells and Jurkat cells than that of CTLs activated by HL-60-peptides (P < 0.05). And the cytotoxicity of CTLs activated by Hut78/Molt4-peptides to Jurkat cells was significantly stronger than that of CTLs activated by either Hut78-peptides or Molt4-peptides alone (P < 0.05). It is concluded that antigen peptides mixtures from leukemia cells can induce specific antitumor CTLs. There exists cross-reactivity among antigen peptides mixtures from different cell lines of the same type leukemia and more cross-reactive antigen peptides could be obtained from more cell lines, suggesting that antigen peptides mixture with broad antigenic spectrum could be prepared by using multiple leukemia cell lines.

Antigens, Neoplasm↗

Leukemia inhibitory factor in long-term adherent layer cultures: increased levels of bioactive protein in leukemia and modulation by IL-4, IL-1 beta, and TNF-alpha.

In the current study, we used a monoclonal antibody-based enzyme-linked immunosorbent assay and bioassay to assess leukemia inhibitory factor (LIF) protein levels, activity, and function in supernatants of 59 adherent layers derived from acute and chronic myelogenous leukemia, myelodysplastic syndrome, and hairy cell leukemia patients and from normal controls. We demonstrate that biologically active LIF protein is constitutively produced and secreted by cultured bone marrow stromal cells from all of the studied subjects. Furthermore, various cytokines can alter endogenous LIF protein levels. Twenty-four h of exposure to recombinant human (rh) interleukin (IL) 4 (100 units/ml) significantly decreased LIF protein levels in adherent layer conditioned media [median base line level, 2.6 ng/ml; range, 1.6-8.0 ng/ml; median post rhIL-4 exposure levels, 1.9 ng/ml; range, 0.9-5.8 ng/ml (n = 7; P = 0.022)]. In contrast, rhIL-1 beta and rh tumor necrosis factor alpha consistently increased LIF protein levels. In the samples exposed to 50 units/ml rhIL-1 beta, median base line LIF level was 2.6 ng/ml; median post-LIF level was 9.0 ng/ml (n = 8; P = 0.014). In the two samples exposed to rh tumor necrosis factor alpha (200 units/ml), LIF levels increased from baseline levels of 2.6 and 2.7 ng/ml to postexposure levels of 7.7 and 12.2 ng/ml, respectively. Finally, the presence of LIF may be relevant to both normal and malignant hematopoietic processes as evidenced by: (a) LIF protein levels in adherent layer conditioned media were significantly elevated in samples from patients with a spectrum of hematological neoplasms [acute myelogenous leukemia: median level, 3.0 ng/ml (range, 1.6-11.0 ng/ml); myelodysplastic syndrome: median level, 4.5 ng/ml (range 1.4-15.5 ng/ml); hairy cell leukemia; median level, 3.5 ng/ml (range 2.2-10.3 ng/ml); chronic myelogenous leukemia-chronic phase: median level, 4.35 ng/ml (range 0.3-19.0 ng/ml); and chronic myelogenous leukemia-blast crisis: median level, 6.25 ng/ml (range 0.7-20.3 ng/ml)] as compared to samples from normal individuals (median level, 2.0 ng/ml; range, 0.7-4.6 ng/ml; P < 0.05); and (b) in normal controls, in vitro abrogation of endogenous LIF bioactivity by neutralizing antibody decreased the number of committed granulocyte-macrophage hemopoietic progenitors.

Blast Crisis↗

Phenotypic heterogeneity of leukemias associated with Friend MuLV infection: studies on T-cell lymphomas and null cell leukemias in euthymic and thymus-deficient mice.

The development of leukemia/lymphoma in euthymic and congenitally thymus-deficient (nude) mice infected with Friend murine leukemia virus (Friend MuLV) was investigated; both groups developed fatal leukemias within 2-4 months post-infection but the gross and micropathology of lymphoid organs, coupled with cell-surface marker studies indicated the development of two distinct forms of disease. In euthymic mice one group developed lymphosarcomas manifested by thymoma, hepatosplenomegaly and lymphadenopathy whereas the second group developed splenic leukemias manifested only by hepatosplenomegaly. Analysis of surface markers on spleen cells from mice experiencing lymphosarcomas indicated that the majority of cells were positive for Thy 1.2, Moloney cell surface antigen (MCSA), and viral-coded gp70 and p30 antigens but negative for surface immunoglobulin (sIg). Euthymic mice experiencing splenic leukemias yielded spleen cells negative for Thy 1.2, sIg, and MCSA but positive for gp70 and p30. Nude mice uniformly developed splenic leukemias, spleen cells from which were Thy 1.2, MCSA, gp70 and p30 negative, although the proportion of sIg positive cells was higher than that observed in euthymic mice experiencing splenic leukemias. No correlation between the development of lymphosarcoma vs splenic leukemia and a pattern of ecotropic and/or xenotropic MuLV expression was observed. While ecotropic MuLV expression was equivalent in both euthymic and athymic mice, euthymic mice expressed approx. 10-fold higher levels of xenotropic MuLV than nude mice, however. Collectively the data suggest that infection of mice with Friend MuLV results in the development of two possible forms of disease, lymphosarcoma involving T cells vs splenic leukemia involving B and/or null cells.

Animals↗

Leukemia cutis: Darier's sign in a neonate with acute lymphoblastic leukemia.

Infantile leukemia accounts for only 3% of childhood leukemia. Leukemia cutis occurs in 25% to 30% of infants with congenital leukemia and is more frequently associated with acute myeloid leukemia than with acute lymphoblastic leukemia. We describe an infant in whom hyperpigmented macules that developed when the patient was 2 weeks old demonstrated Darier's sign when he was 4 weeks old. Acute lymphoblastic leukemia, early pre-B-cell type, was diagnosed when the patient was 10 weeks old. Examination at that age revealed 1 to 2 cm, firm, mildly tender nodules clustered on the scalp, face, and extremities, less severe involvement of the trunk, and marked induration of the face and eyelids. Darier's sign was elicited from the less infiltrated truncal lesions. Histologic examination revealed a dense monomorphous infiltrate consisting of pleomorphic, undifferentiated cells. No mast cells were revealed by Giemsa staining. This case is to our knowledge the first reported example of leukemia cutis demonstrating Darier's sign.

Humans↗

Detection of acute leukemia cells with mixed lineage leukemia (MLL) gene rearrangements by flow cytometry using monoclonal antibody 7.1.

Translocations involving 11q23 are among the most common genetic abnormalities in hematologic malignancies, occurring in approximately 5-10% of acute lymphoblastic leukemia (ALL) and 5% of acute myeloblastic leukemia (AML). In 11q23 translocations, the mixed lineage leukemia (MLL) gene on chromosome 11, band q23, is usually disrupted. The human homologue of the rat NG2 chondroitin sulfate proteoglycan molecule, as detected by the monoclonal antibody (moab) 7.1, was shown to be expressed on leukemic cells with MLL rearrangements of children with acute leukemia. We further investigated the reactivity of the moab 7.1 on 533 cell samples of adults (n = 215) and children (n = 318) with acute leukemias (271 AML, 217 B-lineage ALL, 37 T-lineage ALL, eight CD7+ CD56+ myeloid/natural killer cell precursor acute leukemias) by flow cytometry. In AML, 38 samples were positive for moab 7.1 ('20%-cut-off-level'). These moab 7.1-positive AML cases revealed a myelomonocytic-differentiated immunophenotype with coexpression of the NK cell marker CD56 in 33 of 38 cases. Two of eight cell samples of the recently described CD7+ CD56+ myeloid/natural killer cell precursor acute leukemia entity reacted with moab 7.1. In ALL, 35 samples mostly of the pro-B-ALL subtype (33 pro-B-ALL, one common-ALL, one pre-B-ALL) were positive for moab 7.1. 58 (81%) of 72 samples with MLL rearrangements were positive for moab 7.1 including 28/31 with a t(4;11), 16/17 with a t(9;11), 3/5 with a t(11;19), and 2/6 with a del(11)(q23). All moab 7.1-positive ALL (n = 34) and childhood AML (n = 17) cases revealed MLL rearrangements as detected by Southern blot analysis and RT-PCR. However, 11 adults with AML, and one adult with moab 7.1-positive CD7+ CD56+ myeloid/natural killer cell precursor acute leukemia were negative for MLL rearrangements as proved by Southern blot analysis. We conclude that moab 7.1 is a sensitive but not entirely specific marker for the identification of 11q23-associated AML and ALL by flow cytometry in children and adults.

Acute Disease↗

Destruction of circulating leukemia cells by phagocytosis in rats with myelogenous leukemia.

Acute myelogenous leukemia was induced in outbred Long-Evans rats by iv injections of leukemia cells from a subcutaneous tumor of Shay myelogenous leukemia. In rats with this leukemia the peripheral white blood cell (WBC) counts varied from 2.4 to 700 X 10(9)/liter. No differences were found in the bone marrow of the rats with the high WBC counts and that of rats with low WBC counts. This observation could explain the large variations in the number of circulating leukemia cells caused by differences in cell proliferation or delivery of cells into the circulation. Massive phagocytosis of leukemia cells occurred in animals with low WBC counts (less than 12 X 10(9)/liter) but not in animals with high WBC counts (greater than 150 X 10(9)/liter). This phagocytosis was directed against circulating leukemia cells. The main phagocytes were Kupffer's cells of the liver and macrophages of the spleen parenchyma. In addition, phagocytosis occurred in the spleens and bone marrow by intravascular macrophages, which were derived from extravascular sites. The endothelium of the postcapillary venules of the lymph nodes participated in the phagocytosis of circulating leukemia cells while continuing to be the locus of lymphocytic return from circulation to lymphatic parenchyma. The factors underlying the differences in macrophage activity between the rats with high and low WBC counts were unknown.

Animals↗

Hematogenous development of rat mature granulocytic leukemia--comparison of 2,7-FAA-induced and transplanted leukemia.

The oral administration of N,'N-2,7-fluorenylenebis-acetamide (2,7-FAA) induces leukemia, especially mature granulocytic leukemia in rats. We compared the degree of infiltration of 2,7-FAA-induced mature granulocytic leukemia with that of transplanted leukemia for the purpose of proving hematogenous development of leukemia. The bone marrow, spleen and liver were examined in the cases of diffuse lesion of 2,7-FAA-induced and transplanted leukemia. The average degree of infiltration of both 2,7-FAA-induced and transplanted leukemia was high in the bone marrow, medium in the spleen, and low in the liver. Intravenous transplantation of malignant neoplasm is an example of hematogenous metastasis. The similarity of infiltration between 2,7-FAA-induced and transplanted leukemia suggests that the former is spread by hematogenous metastasis.

2-Acetylaminofluorene↗

The impact of leukemia status at the time of HLA-identical sibling marrow transplantation on subsequent complication rate and survival of adults with acute leukemia.

Between March 1981 and March 1985, 76 patients with acute leukemia were treated with cyclophosphamide (120 mg/kg), 12 or 14 Gy total body irradiation, and an HLA-identical sibling marrow transplant. Forty-seven patients had acute non-lymphoblastic leukemia (ANLL) and 29 had acute lymphoblastic leukemia (ALL). Forty-one were transplanted during first remission and 28 during or after first relapse of their disease. An additional six patients were transplanted because their leukemia was refractory to conventional cytotoxic chemotherapy, and one was transplanted as initial therapy. Actuarial 42 month survival for those transplanted during first remission was 47% and for those transplanted in first relapse or later it was 22% (p = 0.02). There was no difference in either group between those with ANLL and those with ALL. Two of the six patients with refractory leukemia are alive more than 22 and more than 15 months after the transplant. The incidence of acute graft-versus-host disease and interstitial pneumonitis was 90% and 39%, respectively, for the first remission group, and 96% and 37% for those transplanted in first relapse or later. There was no significant difference in transplant-related mortality between the two groups (29% and 43%, respectively). The leukemia recurrence rate, however, was 13% for those transplanted in first remission and 67% for those transplanted in first relapse or later (p = 0.0003). Thus, the major factor determining the incidence of leukemia recurrence and survival after transplant was the status of the leukemia at the time of transplantation.(ABSTRACT TRUNCATED AT 250 WORDS)

Actuarial Analysis↗

Mutation of all Runx (AML1/core) sites in the enhancer of T-lymphomagenic SL3-3 murine leukemia virus unmasks a significant potential for myeloid leukemia induction and favors enhancer evolution toward induction of other disease patterns.

SL3-3 murine leukemia virus is a potent inducer of T-lymphomas in mice. Using inbred NMRI mice, it was previously reported that a mutant of SL3-3 with all enhancer Runx (AML1/core) sites disrupted by 3-bp mutations (SL3-3dm) induces predominantly non-T-cell tumors with severely extended latency (S. Ethelberg, J. Lovmand, J. Schmidt, A. Luz, and F. S. Pedersen, J. Virol. 71:7273-7280, 1997). By use of three-color flow cytometry and molecular and histopathological analyses, we have now performed a detailed phenotypic characterization of SL3-3- and SL3-3dm-induced tumors in this mouse strain. All wild-type induced tumors had clonal T-cell receptor beta rearrangements, and the vast majority were CD3(+) CD4(+) CD8(-) T-lymphomas. Such a consistent phenotypic pattern is unusual for murine leukemia virus-induced T-lymphomas. The mutant virus induced malignancies of four distinct hematopoietic lineages: myeloid, T lymphoid, B lymphoid, and erythroid. The most common disease was myeloid leukemia with maturation. Thus, mutation of all Runx motifs in the enhancer of SL3-3 severely impedes viral T-lymphomagenicity and thereby discloses a considerable and formerly unappreciated potential of this virus for myeloid leukemia induction. Proviral enhancers with complex structural alterations (deletions, insertions, and/or duplications) were found in most SL3-3dm-induced T-lymphoid tumors and immature myeloid leukemias but not in any cases of myeloid leukemia with maturation, mature B-lymphoma, or erythroleukemia. Altogether, our results indicate that the SL3-3dm enhancer in itself promotes induction of myeloid leukemia with maturation but that structural changes may arise in vivo and redirect viral disease specificity to induction of T-lymphoid or immature myeloid leukemias, which typically develop with moderately shorter latencies.

Animals↗

Epistaxis and severe weakness in a patient with multiple myeloma. Therapy-related acute myeloid leukemia, pure erythroid leukemia.

Therapy-related acute myeloid leukemias arise as a result of cytotoxic chemotherapy and/or radiation therapy. The most common types of acute myeloid leukemia arising in this setting are acute myeloid leukemia with maturation, and lesser numbers of acute myelomonocytic leukemia, acute monocytic leukemia, acute erythroleukemia, or acute megakaryocytic leukemia. We present a patient with multiple myeloma who was treated with melphalan and 4 years later developed acute erythroid leukemia. The morphologic diagnosis of pure erythroid leukemia developing in the setting of multiple myeloma may be challenging.

Acute Disease↗

[Study on gene expression of TGF beta 1 and its receptor in leukemia cells and the serum TGF beta 1 level in the patients with acute leukemia].

OBJECTIVE: To investigate the mechanism by which TGF beta 1 inhibits the growth of leukemic cells and the significance of serum TGF beta 1 level in acute leukemia(AL) patients. METHODS: RT-PCR was used to detect gene expression of cytokines including IL-1, IL-3, IL-6, TGF beta 1 and their receptors (R) in leukemic and normal cells. Leukemic colony assay was carried out to determine the effect of TGF beta 1 on the growth of leukemic cells and the serum TGF beta 1 level in 33 AL patients were measured by ELISA. RESULTS: TGF beta 1 was found to significantly inhibit the proliferation of leukemia cells of HL-60, K562 and DAMI cell lines. Furthermore, a variety of leukemia cell lines including HEL, HL-60, K562, U937, DAMI, MEG-01, HUT78 and CA were found to express mRNAs for TGF beta 1 and its receptor. In addition, TGF beta 1 was found to be able to evidently down-regulate the expression of mRNAs for IL-6, IL-6R, IL-3, GM-CSFR in DAMI cells and, interestingly, up-regulate TGF beta 1 gene expression in the cells per se before the cells showed DNA fragmentation, a molecular hallmark for cell apoptosis. It was shown that serum TGF beta 1 levels were significantly decreased in leukemic patients, restored to normal in the patients achieved complete remission, and tended to decrease again in the recurrent patients. CONCLUSION: 1. TGF beta 1 may act as an inhibitory autocrine factor in the proliferation of leukemia cells; 2. the mechanism by which TGF beta 1 inhibits the growth of leukemia cells involves its down-regulating expression of positive cytokines and receptors and up-regulating TGF beta 1 expression in leukemia cells per se; 3. serum TGF beta 1 is a valuable parameter in monitoring the prognosis of leukemia and weakened control of TGF beta 1 on leukemia cells may play an important role in the pathogenesis of AL.

Adult↗