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)

The production of interleukin 1 (IL-1) by lipopolysaccharide (LPS)-stimulated myelomonocytic cell lines ML-1, THP-1 and PL-21 was significantly enhanced by the addition of insulin, insulin-like growth factor (IGF)-I or IGF-II into the cell cultures. The IL-1 activity in the supernatants from cell cultures stimulated with LPS and insulin was completely neutralized by anti-IL-1 beta antibody. Anti-IL-1 alpha antibody had no inhibitory effect. Insulin itself did not stimulate IL-1 beta production directly, but increased it in the mitogen activated cells. However, insulin had no enhancing effect on the production of IL-1 alpha by human T cell lymphotropic virus-I (HTLV-I)-infected T cell lines or on IL-2 production by mitogen-stimulated leukemia T cell lines. Thus, insulin and its related cytokines are shown here as other molecules selectively modulating the production of IL-1 beta in myelomonocytic cell lines.
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PMID:Selective enhancement of interleukin 1 beta production in myelomonocytic cell lines by insulin and its related cytokines. 148 10

As the number of long-term survivors of childhood leukemia increases, growth retardation has emerged as a significant complication. Treatment of these children with growth hormone (GH) has been suggested and sporadically implemented. We, therefore, studied the effect of human GH (hGH) and its by-product insulin-like growth factor-1 (IGF-1) on the growth of leukemic cells in vitro. Under serum-free conditions hGH and IGF-1 induced a significant dose-dependent proliferative effect on promyelocytic leukemia (HL60) and Burkitt's lymphoma (Daudi) cell lines. Anti-hGH antibodies negated the stimulatory effect of hGH and anti-IGF-1 serum abrogated the growth-promoting effect enhanced by IGF-1. Similar statistically significant stimulatory properties were found when freshly obtained marrow cells from four of five acute lymphoblastic leukemia (ALL) of childhood and four acute myelogenous leukemia (AML) patients were studied in ALL and AML blast-cell clonogenic assays. ALL colonies increased numerically by 72% (P less than .025) and AML colonies by 92% (P less than .01) in the presence of hGH at concentrations of 2.5 x 10(2) and 3.0 x 10(2) ng/mL, respectively. IGF-1 stimulated ALL and AML blast-colony growth at concentrations ranging from 0.05 to 0.5 ng/mL by up to 105% (P less than .025) and 65% (P less than .03), respectively. Our in vitro data suggest that circulating hGH and IGF-1 may promote leukemic blast cell replication in vivo, and the supplemental administration of hGH to leukemia patients in remission must be carefully monitored for early relapse.
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PMID:Human growth hormone and insulin-like growth factor-1 enhance the proliferation of human leukemic blasts. 199 9

In the absence of serum, growth of ML-1 human myeloblastic leukemia cells is induced by the insulin-like growth factor-1 (IGF1) together with transferrin (Tf), whereas monocytic differentiation is initiated by the transforming growth factor-beta (TGF-beta) in combination with Tf. Initiation of growth was followed by the rapid release of arachidonic acid (AA), hydroxyeicosatetraenoic acids (HETEs) and phospholipids into the culture medium. In contrast, induction of differentiation occurred without the release of these lipids beyond the level present in control. Inhibitors of enzymes involved in the formation of AA and of HETEs, including phospholipase A2 and lipoxygenases, caused interference with growth but not with differentiation, and an inhibitor of the cyclooxygenase path affected neither growth nor differentiation. These results indicate that the initiation of ML-1 cell growth but not of cell differentiation is dependent upon the increased formation of AA and its derivatives formed primarily via the lipoxygenase path.
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PMID:Differential effect of growth- and differentiation-inducing factors on the release of eicosanoids and phospholipids from ML-1 human myeloblastic leukemia cells. 811 43

Several epidemiologic studies have demonstrated that high birthweight is associated with an increased risk of infant leukemia; however, the reason for this relationship is unclear. Biologic data demonstrate that birth weight is correlated positively with circulating levels of insulin-like growth factor-1 (IGF-1). IGF-1 is important in blood formation and regulation and has been shown to stimulate the growth of both myeloid and lymphoid cells in culture. Since infants who develop leukemia are likely to have had at least one transforming event occur in utero, we hypothesize that high levels of IGF-1 may both produce a larger baby and contribute to leukemogenesis.
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PMID:Big babies and infant leukemia: a role for insulin-like growth factor-1? 887 54

The processes leading to implantation and the establishment of pregnancy involve hormonal and non-hormonal agents that offer opportunities as targets for contraception. Hormonal agents include progesterone, luteolytic factors (prostaglandin F2 alpha) and embryonic signals (chorionic gonadotrophin, oestradiol-17 beta, interferon-tau) responsible for maintaining the corpus luteum. Non-hormonal agents include surface antigens (attachment and adhesion molecules), vasoactive agents, tissue-remodelling enzymes (matrix metalloproteinases) and inhibitors (TIMPs), growth factors (epidermal growth factor and insulin-like growth factor families) and cytokines (such as leukaemia inhibitory factor, colony-stimulating factor-1, interleukin-1 (IL-1) and IL-6) associated with the pre-attachment period and the apposition, adhesion and invasion of the blastocyst. This review describes some of the hormonal and non-hormonal agents present at the time of implantation that may be exploited as targets for contraception in feral species. Particular attention is paid to the mouse as an experimental model and potential target species. The considerable species differences which exist in the models of implantation and placentation and the way in which the female 'recognizes' the presence of a viable conceptus offer a means of conferring species specificity on potential contraceptive targets for feral species.
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PMID:Hormonal and non-hormonal agents at implantation as targets for contraception. 910 95

The level of various G1 cyclins and cyclin-dependent kinases (cdks) present in the nuclei of synchronized ML-1 human myeloblastic leukemia cells was determined as a function of time after initiation of cell growth with insulin-like growth factor-1 (IGF-1) and transferrin (Tf), and following induction of differentiation with transforming growth factor-beta1 (TGF-beta1). Cyclin E and cdk2 were expressed at relatively high levels in the nuclei of proliferation-stimulated cells, whereas cyclin D1 and cdk5 were expressed at comparably high levels in the nuclei of differentiation-induced cells. In the nuclear extracts from proliferation-stimulated cells, cyclin E complexed specifically with cdk2, whereas in nuclear extracts from differentiation-induced cells, cyclin D1 bound specifically to cdk5. Increased cyclin E/cdk2 expression was accompanied by increased DNA synthesis, whereas increased cyclin D1/cdk5 levels correlated with decreased DNA synthesis. In both growth- and differentiation-induced cells, cyclin D2 expression preceded the expression of cyclin D3, and a significantly larger amount of these cyclins was present in differentiation- as compared to proliferation-induced cells. In contrast, cdk4 and cdk6 were present at similar levels in the nuclear extracts from both growth- and differentiation-induced cells. These data show that, in ML-1 cells, the proliferation-associated progression from G1 to S, as well as the differentiation-associated transit from G1 to maturation is accompanied by the expression of specific cyclin/cdk pairs, comprising cdk2/cyclin E in growth and cdk5/cyclin D1 in differentiation.
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PMID:Differential expression of proteins regulating cell cycle progression in growth vs. differentiation. 915 Feb 73

Interleukin (IL)-6, a cytokine produced by skeletal cells and known to increase bone resorption, has mitogenic effects for bone cells, possibly by regulating the synthesis of other local factors. We tested the effects of IL-6 and its soluble receptor (IL-6sR) on the expression of insulin-like growth factor (IGF)-I and IGF-II in cultured osteoblast-enriched cells from fetal rat calvariae (Ob cells). IL-6 did not modify IGF-I messenger RNA (mRNA) levels, but when tested in the presence of IL-6sR, IL-6 at 1 to 100 ng/ml increased IGF-I transcripts by up to 3.2-fold after 24 h. IL-6sR caused a small increase in IGF-I mRNA levels when tested alone. IL-6 and IL-6sR increased immunoreactive IGF-I levels by 2.4-fold after 24 h and 6.4-fold after 48 h. Cycloheximide prevented, and indomethacin markedly decreased, the effect of IL-6 and IL-6sR on IGF-I mRNA levels, but hydroxyurea did not. IL-6 and IL-6sR did not alter the decay of IGF-I mRNA in transcriptionally arrested Ob cells, and the half-life of the predominant 6.5-kb IGF-I transcript was about 11 h in control and treated cells. In addition, IL-6 and IL-6sR increased the levels of IGF-I heterogeneous nuclear RNA. IL-11 also increased IGF-I mRNA levels, whereas oncostatin M and leukemia-inhibitory factor did not. In contrast to their effects on IGF-I, IL-6 and IL-6sR caused only a modest increase in IGF-II mRNA and polypeptide levels. In conclusion, IL-6, in the presence of IL-6sR, increases IGF-I synthesis in Ob cells; this effect may lead to a secondary increase in bone formation.
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PMID:Interleukin-6 with its soluble receptor enhances the expression of insulin-like growth factor-I in osteoblasts. 938 8

Defining how the stromal requirements of hematopoietic progenitors change during leukemia progression is an important topic that is not well understood at present. The murine ELM erythroleukemia is an interesting model because the erythroid progenitors retain dependence on bone marrow-derived stromal cells for long-term growth in vitro, and they also undergo erythroid differentiation in the presence of erythropoietin (EPO) and interleukin-3 (IL-3). In this report, we have shown using neutralizing antibodies that stem cell factor (SCF), insulin-like growth factor (IGF)-1, and integrin signaling pathways are all involved. We then determined whether ELM cells can be maintained long-term without stroma in various combinations of growth factors produced by stroma cells or growth factors for which ELM cells have receptors. This showed that ELM cells could be maintained with high efficiency in SCF alone; furthermore, the cells remained absolutely SCF-dependent and did not become more tumorigenic than cells maintained on stroma. In contrast, ELM cells underwent clonal extinction when serially cloned in IGF1; any cells that survived long-term growth in IGF-1 were found to be IGF1-independent. One important difference between maintaining ELM cells on stroma and growth in SCF is that stroma reversibly inhibits their differentiation in response to EPO and IL-3, whereas SCF does not.
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PMID:Both stroma and stem cell factor maintain long-term growth of ELM erythroleukemia cells, but only stroma prevents erythroid differentiation in response to erythropoietin and interleukin-3. 947 19

We recently found evidence indicating that the source of elevated serum insulin-like growth factor binding protein (IGFBP)-2 in leukemia was the leukemic T-cells. Here we report that locally produced IGF-II affects IGFBP-2 expression and growth of leukemic cells through the IGF type I receptor. We measured IGFBP-2, -4 and IGF type I receptor (IGF-I-R) mRNA by RT-PCR, cell growth and IGFBP-2 secretion (per 10(6) cells). IGF-I-R binding sites were assessed by 125I-IGF replacement studies. Inhibition using an IGF-II antibody showed that tumor cell-derived IGF-II accounts for a significant 25% (P < 0.001) increase in IGFBP-2 secretion and enhanced growth (P < 0.01) of leukemic T-cells after 7 days in culture. IGFBP-2 secretion, but not IGFBP-2 mRNA was specifically increased by IGFs, while no specific effect of insulin was detectable. The addition of 100 ng/ml IGF-II enhanced the IGFBP-2 secretion 2.8-fold, while the use of IGF-I only enhanced IGFBP-2 secretion 1.7-fold, although IGF-I enhanced IGF-II action. Through inhibition using JB1, a peptide inhibiting the IGF signal transduction by blocking the IGF-I-R, we demonstrated the involvement of the IGF-I-R in IGFBP-2 and -4 expression and leukemic cell growth. However, only slight differences in the IGF-I-R mRNA expression were seen for T- and B-cells compared with the differences found for the IGFBP-2 and -4 mRNA or IGFBP-2 secretion. Thus, although IGF-I-R mediates the autocrine/paracrine effects of the IGFs, IGF-I-R mRNA expression is most probably not involved in the differential IGFBP-2/IGFBP-4 expression in leukemic cells.
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PMID:Elevated insulin-like growth factor (IGF) binding protein (IGFBP)-2 and IGFBP-4 expression of leukemic T-cells is affected by autocrine/paracrine IGF-II action but not by IGF type I receptor expression. 953 10

Human ovarian adenocarcinoma cells N.1 secrete an autocrine activity that stimulates active cell death under serum-reduced conditions. To substitute the autocrine activity by a single physiological component, 28 cytokines, growth factors and biomodulators were tested [interleukin 1alpha (IL-1alpha), IL-1beta, IL-2, IL-3, IL-4, IL-6, IL-10, IL-11, stem cell factor (SCF), platelet-derived growth factor (PDGF), acid fibroblast growth factor (aFGF), basic fibroblast growth factor (bFGF), insulin-like growth factor (IGF-1), IGF-2, insulin, macrophage colony-stimulating factor (M-CSF), granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), oncostatin, RANTES (regulated on activation normal T cell expressed and secreted), angiogenin, leukaemia inhibitory factor (LIF), erythropoietin (EPO), interferon alpha (INF-alpha), INF-gamma, transferrin, tumour necrosis factor alpha (TNF-alpha, TNF-beta and bovine serum albumin for control reasons]. In these experiments, only TNF-alpha and TNF-beta rapidly induced apoptosis. TNF-alpha and TNF-receptor 1 were expressed by N.1 cells, and the secretion of TNF-alpha was verified by enzyme-linked immunosorbent assay (ELISA). Autocrine factor-triggered apoptosis was inhibited when conditioned supernatant was preincubated with anti-TNF-alpha antibody. These findings suggested that the apoptosis-inducing component of the N.1 autocrine activity was TNF-alpha. In the presence of antisense c-myc oligonucleotides, induction of cell death by autocrine factor was partly inhibited. Autocrine factor and TNF-alpha stimulated transcription of the invasiveness-related protease plasminogen activator/urokinase mRNA (upa) with similar kinetics. When N.1 cells were exposed to purified plasminogen activator/urokinase protein (uPA), cell matrix contact was disrupted. Thus, uPA might serve a physiological role during TNF-induced apoptosis by affecting the interactions between cells and the basal membrane, thereby facilitating anoikis. This mechanistic study, which was restricted to a single human ovarian carcinoma model cell line (N.1), provides evidence that N.1 maintains the capacity to undergo c-myc-dependent apoptosis by the TNF-TNF-receptor pathway, and no additional pharmacological stimuli for induction of apoptosis are required.
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PMID:Autocrine self-elimination of cultured ovarian cancer cells by tumour necrosis factor alpha (TNF-alpha). 976 76


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