Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Four human chronic myeloid leukemia (CML) cell lines, BV173, K562, KCL-22, and KYO-1, were studied for inactivation of human tumor suppressor gene p53. Southern blotting showed allele deletion in KCL-22 and cytogenetic studies showed a chromosome 17 deletion in KYO-1 but no gross structural abnormalities in the other two lines. Northern blotting showed increased amounts of normal size p53 mRNA in BV-173 and KYO-1, trace amounts in KCL-22, and none in K562. Direct sequencing of p53 cDNA revealed a missense point mutation in KYO-1 and a single base pair deletion consistent with a coding frame shift in KCL-22. Both abnormalities in these myeloid cell lines were located in the highly conserved region of p53. Studies with two monoclonal antibodies showed that the three cell lines with p53 mRNA had readily detectable p53 proteins. In KYO-1 and BV173 cells the p53 protein was located mainly in the nuclei but KCL-22 cells had weak staining in the cytoplasm. Our data support the assumption that inactivation of p53 tumor suppressor function in myeloid blast transformation of CML may result from point mutations or deletions that produce mutant proteins.
Leukemia 1992 Aug
PMID:p53 in chronic myeloid leukemia cell lines. 164 Jul 38

Tumor cell resistance due to enhanced efflux of drugs with diverse structures and/or mechanisms of action is termed multidrug resistance (MDR), and modulation of the MDR phenotype by calcium blockers or calmodulin inhibitors is suggested to involve P-glycoprotein. In drug-sensitive (S) and 5-fold doxorubicin (DOX)-resistant (R0) L1210 mouse leukemia cells, no obvious differences in mdr mRNA or P-glycoprotein expression or alterations in cellular uptake, retention, or cytotoxicity of vincristine (VCR) were observed. However, in the 10-fold (R1) and 40-fold (R2) DOX-resistant sublines, expression of P-glycoprotein was correlated with the level of resistance (R2 greater than R1). An RNase protection assay revealed that elevated levels of mdr1 and mdr2 mRNA were detected in R1 and R2 cells, with an additional increase in mdr3 mRNA in the R2 subline. Further, in the R1 and R2 sublines, no VCR dose-dependent cytotoxicity was apparent, and cell kill of greater than 40% was not achievable following a 3-hr drug exposure. Cellular uptake and retention of VCR were 2- to 4-fold lower in the R1 and R2 sublines, compared with similarly treated S or R0 cells. Potentiation of VCR cytotoxicity by a noncytotoxic concentration of 5 microM trifluoperazine (TFP) was greater than 2-fold in S and R0 cells and less than 1.3-fold in the R1 and R2 sublines. Modulation of VCR uptake by 5 microM TFP in the S and R0 cells was 2-fold and it was 4- to 7-fold in the R1 and R2 sublines. The presence of 5 microM TFP, by competing for efflux, enhanced VCR retention 1.5-fold in S and R0 cells and 2- to 4-fold in the R1 and R2 sublines. In contrast to these results with VCR, dose-dependent cytotoxicity of DOX was apparent in all the resistant sublines, and modulation of DOX cytotoxicity by 5 microM TFP was dependent on the level of resistance. Cellular accumulation of DOX was 20 and 50% lower in the R1 and R2 sublines, respectively, compared with similarly treated S or R0 cells. Marked increases (greater than 1.5-fold) in cellular accumulation of DOX by TFP were apparent only in the R2 subline. Results suggest that a relationship between overexpression of P-glycoprotein isoforms and their role in affecting cellular drug levels and consequent cytotoxicity in MDR L1210 cells determines resistance to VCR but not DOX.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Relationship between expression of P-glycoprotein and efficacy of trifluoperazine in multidrug-resistant cells. 167 Sep 62

The leucocyte adhesion molecule LFA-1 (CD11a/CD18) and its counter structure ICAM-1 (CD54) play a pivotal role in cell-cell interactions in the immune system and hence their expression on malignant cells might play an important role in determining the biological behavior of lymphoid malignancies. This study examined the LFA-1 (CD11a/CD18) and ICAM-1 (CD54) expression profiles of a large series of non-Hodgkin's lymphomas (NHL, n = 220) and lymphoid leukemias (LL, n = 48), which, by their differentiation-antigen phenotype represented essentially all stages of lymphoid development from stem cell to mature activated T- and B-lymphocyte. It was found that NHL and LL differentially express LFA-1 and ICAM-1 molecules according to their lineage derivation, stage of differentiation, and growth pattern. Specifically: (a) T-cell neoplasms nearly always express LFA-1 whereas B-cell tumors are often LFA-1 low/negative; (b) ICAM-1 expression is largely confined to tumors with a mature or activated T- or B-cell phenotype; (c) neoplasms with a leukemic dissemination pattern are either ICAM-1 low or negative. Importantly, neither LFA-1 nor ICAM-1 expression was related to tumor grade.
Leukemia 1991 Oct
PMID:Expression of the leucocyte integrin LFA-1 (CD11a/CD18) and its ligand ICAM-1 (CD54) in lymphoid malignancies is related to lineage derivation and stage of differentiation but not to tumor grade. 168 77

In this study we demonstrate that tumor necrosis factors (TNF alpha and TNF beta) are potent modulators of the in vitro proliferation of human AML cells. Blast cells from 11 cases of acute myeloblastic leukemia (AML) were incubated with recombinant TNF alpha or TNF beta in serum-free 3H-TdR uptake and colony culture systems in the presence or absence of recombinant interleukin-3 (IL-3), granulocyte macrophage colony-stimulating factor (GM-CSF), G-CSF, or M-CSF. Depending on the supplemented CSF, TNF could upregulate or suppress AML blast proliferation. Enhancement of AML growth by TNF was observed in the presence of IL-3 (in 9 of 11 cases in 3H-TdR assay; 6 of 9 cases in colony assay) and GM-CSF (in 8 of 11 cases in 3H-TdR assay; 4 of 9 cases in colony assay). In certain cases in which IL-3 or GM-CSF alone was unable to induce proliferative responses of AML cells, the simultaneous addition of TNF elicited colony growth and DNA synthesis suggesting a synergistic action between TNF and IL-3 or GM-CSF. In contrast, TNF suppressed G-CSF-induced growth (9 of 10 cases in 3H-TdR assay; 5 of 6 cases in colony assay). TNF could also stimulate DNA synthesis (in 2 of 11 cases) or colony formation (in 2 of 9 cases) in AML cultures without the addition of other growth factors. Experiments with neutralizing antibodies and specific radioimmunoassays for individual CSFs showed that the synergistic and antagonistic effects of TNF on AML growth could not be attributed to a release of one of these CSFs by the AML cells. The opposing consequence of exposure of AML blasts to TNF are of interest in view of our understanding of the pathophysiology of AML growth and the in vivo application of recombinant cytokines in AML patients.
Leukemia 1990 Jan
PMID:Modulation of colony stimulating factor-(CSF) dependent growth of acute myeloid leukemia by tumor necrosis factor. 168 38

In order to obtain more insight into the nature of the abnormal in vitro colony formation in myelodysplastic syndromes (MDS), we investigated the kinetics of the colony formation of 23 MDS cases in response to recombinant human interleukin-3 (IL-3), Granulocyte-macrophage colony-stimulating factor (GM-CSF), granulocyte colony-stimulating Factor (G-CSF), and giant cell tumor cell line conditioned medium (GCT-CM). The kinetics of GCT-CM-induced colony formation were comparable to that of G-CSF-induced colony growth, both in MDS and in normal bone marrow cultures. Colony formation was found to be delayed in MDS. The delay in colony formation was most apparent in the GCT-CM (G-CSF) responsive progenitor cell compartment. In MDS cases with clinical features of high risk disease, this delay was more pronounced as compared with low risk cases (7 and 3 days, respectively, in response to GCT-CM). The delay in colony formation was found to be caused by an increase in the time interval before progenitor cells had begun to divide. These results suggest that a prolongation of the time spent in G0 of myeloid progenitor cells in MDS may be the cause of the indolent in vitro colony formation observed in this disease.
Leukemia 1990 Apr
PMID:The effects of interleukin-3, GM-CSF, and G-CSF on the growth kinetics of colony-forming cells in myelodysplastic syndromes. 169 40

We established two human plasma cell lines, FR4 and AD3, from ascitic fluid in a patient with IgA k plasmacytoma (PC). Aberrant amylase production was found in this patient. Both AD3 and FR4 were free of Epstein-Barr virus, and both produced Ig A k in vitro. They produced amylase of the salivary type in vitro. This was confirmed by the demonstration of amylase mRNA comigrating with salivary gland mRNA. These cell lines commonly had unusual chromosomal abnormalities der(14)t(8;14) and dic(8)t(1;8). AD3 had additional chromosomal abnormalities compared with FR4. This suggests that AD3 is a subline of FR4. The oncogene c-myc is rearranged in most case of Burkitt's lymphoma with t(8;14). However, neither rearrangement nor amplification of the c-myc allele was detected in our PC lines. These lines expressed c-myc of 2.4 kb. There were no structural changes in the amylase genes of AD3 and FR4 detectable with Southern blotting analysis. As these lines were authentic PC lines, they would be useful for the future study of the relationship between the mechanism of oncogenesis and the rare tumor aberration, amylase production.
Leukemia 1990 Aug
PMID:Amylase-producing plasmacytoma cell lines, AD3 and FR4, with der(14)t(8;14) and dic(8)t(1;8) established from ascites. 169 13

A range of potent immunoregulatory molecules termed cytokines has become available for the therapy of human melanoma. Among the cytokines, the interferons (IFN) have been examined in great depth for the therapy of melanoma. IFN are able to modulate host effector cell function, including the tumor cytolytic function of lymphocytes and monocytes. IFN also have the capacity to regulate the distribution of circulating immunoregulatory (T) lymphocytes and the expression of tumor cell surface antigens, as well as class I and II products of the major histocompatibility locus. These activities of the IFN have led to their early application for treatment of human melanoma. The empirical evidence that IFN alpha exerts clinically significant anti-tumor effects against melanoma is reviewed, and evolving status of adjuvant trials of IFN alpha and gamma is noted. New indirect host-mediated anti-tumor activities that may potentially be manifest by IFN have yet to be fully harnessed. The opportunity to obtain meaningful anti-tumor activity in advanced disease or adjuvant settings, at dose ranges below those which are toxic (conventional maximal tolerable), are at hand. The U.S. cooperative groups [Eastern Cooperative Oncology Group (ECOG), Cancer and Leukemia Group B (CALGB), and South West Oncology Group (SWOG)] are studying IFN gamma in pursuit of this goal in advanced and adjuvant settings for melanoma and other tumors. The determination of the clinical role of IFN as biologic response modifiers demands equal commitment to the clinical assessment of immunobiologic mechanisms and anti-tumor effects. The immunologic assessment of IFN and a number of other cytokines is a major focus of the Pittsburgh Cancer Institute. Regional delivery of cytokines such as interleukin-2 (IL-2) may be the most appropriate and least toxic approach, given their half-life. Regional therapy by the intralesional route has yielded enhanced activity for a range of biologics, including bacillus Calmette-Guerin (BCG), IL-2, and tumor necrosis factor (TNF). Intralymphatic therapy with methanol extraction residue of BCG (MER-BCG) has been tested, and trials are now in progress with IL-2 to assess the optimal dosage by this route. It is likely that the optimal role of IFN and other cytokines will be found in combination with one another, and with different biologic modalities such as monoclonal antibodies and vaccines, to allow expansion and heightened activity of the desired effector cell populations in the host. Enhanced host toxicities, as well as anti-tumor effects, may require that special attention be devoted to optimal sequence of administration to enhance the therapeutic index.
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PMID:Role of interferons in the therapy of melanoma. 170 5

Ultrastructural, flow cytometric, and molecular studies were performed on leukemia cells from bone marrow and pleural effusion of a 6-year-old boy diagnosed with undifferentiated (MO) leukemia, using routine histology and immunostains at diagnosis and relapse. Ultrastructurally, surface and/or intracellular ferritin particles were present on or in some blasts and the majority of blasts contained identifiable acid ferrocyanide reactive inorganic iron comparable to that seen in normal early erythroblasts. The cells lacked other evidence of differentiation, including diaminobenzidine-reactive or immunoreactive hemoglobin. Flow cytometric analysis of malignant cells showed a lack of lymphoid or myeloid markers. Anti-transferrin receptor antibody was positive on 93% of cells and antibody to glycophorin A reacted with 23% of cells. RNA blot analysis of leukemia cells with myeloperoxidase (MPO) showed an absence of appreciable levels of MPO mRNA. Chromosome analysis showed 51,XY, t(1;16)(p31;q24), +6, +10, +15, +19, +21. The oncogene c-myb, which is specifically expressed and regulated in hematopoietic cells and produces a DNA-binding protein responsible for myeloid differentiation, was found to be duplicated in the patient's tumor cells. Expression of c-jun, N-ras, c-myc, and p53 was normal. The data indicate that the malignant cells in this patient are of early erythroid lineage at diagnosis and relapse and that classification of cell lineage can be enhanced by ultrastructural Prussian blue staining. The failure of this otherwise undifferentiated leukemia to express or evolve into a myeloid phenotype is biologically and clinically distinct from previously described cases of erythroid and myeloid leukemia and may represent a previously unidentified phenotype which should be included in the spectrum of 'undifferentiated' childhood leukemia.
Leukemia 1991 Feb
PMID:Childhood undifferentiated leukemia with early erythroid markers and c-myb duplication. 170 34

A study of the predictive value for CR, DFS and OS of the presenting features was carried out on 180 patients with advanced stage DLCL treated with MACOP-B between June 1986 and March 1989. A multivariate regression analysis identified LDH level, bone marrow involvement and tumor burden as independent risk factors with a 4 year survival rate of 79%, 58% and 28% respectively. Therefore MACOP-B proved to be an adequate treatment for the first two groups of patients but not for the third which requires a more aggressive treatment. A sequential single drug high dose chemotherapy with collection of peripheral blood stem cell program followed by bone marrow harvesting, super-intensive radio-chemotherapy and bone marrow transplant has been activated. Seven patients have been so far enrolled: preliminary results demonstrated the feasibility of the program. A larger number of cases and a longer follow-up is required for assessing the efficacy of this approach.
Leukemia 1991
PMID:MACOP-B for advanced stage large cell lymphoma (DLCL). More is better? Italian Multiregional Cooperative Study Group (IMCSGL). 171 39

Eighty previously untreated patients with B-cell chronic lymphocytic leukemia (B-CLL) were analyzed to study the proliferation rate of their peripheral blood (PB) leukocytes to determine its relationship with the extension of the disease and its value in discriminating among patients with similar tumor cell mass. The 80 B-CLL patients were distributed into two different groups according to the absolute count of PB S-phase leukocytes: a low proliferative group (less than 1 x 10(9)/I) of 48 patients and a high proliferative group (greater than or equal to 1 x 10(9)/I) of 32 patients. The high proliferative group displayed a higher incidence of splenomegaly (p less than 0.005), hepatomegaly (p less than 0.08), anemia (p less than 0.02) and thrombocytopenia (p less than 0.03) as well as a higher lymphocytic infiltration both in PB (p less than 0.0004) and in bone marrow (BM) (p less than 0.003). These patients also showed a higher incidence of a diffuse pattern of BM involvement (p less than 0.04), advanced clinical stages [stage III/IV (p less than 0.03) and group C (p less than 0.04)] and infections (p less than 0.0008) together with significantly lower IgG (p less than 0.03) and IgM (p less than 0.03) serum levels. Regarding the immunophenotype, there was a greater percentage of either CD19+ (p less than 0.06) and CD19+ CD5+ (p less than 0.05) B-cells, together with a greater reactivity for both the CD25 (p less than 0.04) and CD9 (p less than 0.08) antigens in the high proliferative group. According to the prognostic value of the PB S-phase leukocyte count it was seen that patients with low S-phase white blood cell (WBC) numbers displayed a significantly higher survival (p less than 0.03). In addition, multivariate analysis revealed that the S-phase WBC count, although partially related to other clinical and biological prognostic factors, displayed an important independent value in predicting early deaths in patients with B-CLL.
Leukemia 1992 Jan
PMID:Prognostic value of S-phase white blood cell count in B-cell chronic lymphocytic leukemia. 173 13


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