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)

Platelet-derived growth factor (PDGF), a potent mitogen for mesenchymal cells, consists of PDGF-1 and PDGF-2 polypeptide chains which are linked by disulfide bonds. Sequence analysis has revealed that: (a) the PDGF-2 chain is encoded by the c-sis protooncogene, the cellular counterpart of the simian sarcoma viral oncogene; (b) the PDGF-1 and PDGF-2 chains are related; and (c) the PDGF-1 gene has no known viral homologue. We have previously shown that the PDGF-2 gene is expressed during 12-O-tetradecanoylphorbol-13-acetate (TPA) induced monocytic differentiation of human HL-60 leukemia cells. In the present study, PDGF-1 and PDGF-2 gene expression was compared in HL-60 cells, human THP-1 monocytic leukemia cells, and human monocytes. Uninduced HL-60 cells, uninduced THP-1 cells, and resting monocytes had no detectable PDGF-1 or PDGF-2 mRNA. In contrast, both PDGF-1 and PDGF-2 transcripts were detected in HL-60 cells and monocytes induced with TPA, while only PDGF-1 mRNA was found in TPA-treated THP-1 cells. Moreover, neither of these transcripts were found during drug induced granulocytic differentiation of HL-60 cells. Cycloheximide, an inhibitor of protein synthesis: (a) failed to increase PDGF-1 and PDGF-2 mRNA levels in uninduced HL-60 cells; (b) increased PDGF-2, but not PDGF-1, mRNA in resting monocytes; and (c) increased levels of PDGF-1 and PDGF-2 mRNA in HL-60 cells and monocytes treated with TPA. This effect of cycloheximide was related in part to stabilization of both transcripts. Thus, PDGF-1 and PDGF-2 genes are differentially regulated in myeloid cells, although they share common control mechanisms at the post-transcriptional level. Differential regulation of PDGF gene expression would result in altered chain composition of the PDGF protein and possibly changes in biological activity.
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PMID:Expression of the platelet-derived growth factor 1 and 2 genes in human myeloid cell lines and monocytes. 316 51

The relationship between accumulation, retention and cytotoxicity of various anthracyclines was investigated in Friend leukaemia cells growing in vitro. By comparison to that of adriamycin (ADM) and epi-adriamycin (Epi-ADM), the uptake of demethoxy-daunorubicin (DM-DNR) and THP-adriamycin (THP-ADM) is a rapid process. In cells exposed to DM-DNR or THP-ADM, a 50% accumulation is reached in less than 2 min, whereas 80 min and up to 4 hours are needed for epi-ADM or ADM, respectively. More than 95% of these anthracyclines are accumulated and retained in the nuclear fraction. Following a short cell exposure, the intracellular concentrations of the rapidly incorporated drugs (DM-DNR or THP-ADM) decrease with the cell density. After cell exposure to one of these drugs followed by growth in drug-free medium, the cytotoxic activity is related to the ease with which the anthracycline accumulates in cells. Since the pharmacological properties of these anthracyclines differ, and because cytotoxic activity correlates with these properties, plasma and intracellular concentrations of ADM and THP-ADM were studied after intravenous administration in leukaemic and non-leukaemic patients with various white blood cell concentrations. Since the pharmacokinetic studies in vivo correlated to in vitro parameters, it is concluded that administration modalities have to be determined, adapted to each patient, and considered differently according to the anthracycline used.
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PMID:Relationship between the intracellular accumulation of anthracyclines and effectiveness in vitro and in vivo. 346 Jul 52

Antiserum to a synthetic peptide that defines a hydrophilic region within the putative c-myb translation product was prepared in the rabbit. In lysates from exponentially growing ML-1, human myeloblastic leukemia cells, the antiserum ("anti-myb") reacted with five proteins of Mr 58,000, 75,000, 85,000, 90,000 and 105,000. Of these, only p75 and a trace of p85 were detected, by immunoblotting, in extracts derived from ML-1 cell nuclei. The proteins p58, p75 and p90 were present in readily detectable amounts only in the relatively immature myeloid cell lines ML-1 and HL-60, whereas in the more mature myeloid cell line THP-1 and in the lymphoid line BALL-1 only traces of these proteins were found. p85 and p105 were detected in lysates from all cell lines tested, including myeloid and lymphoid leukemia cells and mouse 3T3 cells. In lysates from ML-1 cells induced to differentiate to monocyte/macrophages or to granulocytes, the concentrations of p58 and p75 decreased in parallel with the cell population moving to maturity; in completely mature populations these two proteins were no longer detectable. In ML-1 cells arrested in G1 by serum depletion, the amount of p58 and p75 and to a smaller extent that of p90 was decreased, whereas the concentration of p85 and p105 remained unchanged. In nuclei from exponentially growing ML-1 cells, the antiserum or its derived immunoglobulin fraction ("anti-myb IgG") inhibited mRNA transcriptional activity by 30%. DNA synthesis was not affected. In contrast, in nuclei from differentiated ML-1 cells, the mRNA transcriptional activity was not significantly inhibited by anti-myb IgG. Similarly, in nuclei from ML-1 cells arrested largely in G1 by serum depletion for 2 days, mRNA transcriptional activity was inhibited by only 11%. Upon supplementation with serum, the mRNA transcriptional activity inhibitable by anti-myb IgG increased in parallel with the increasing rate of cell growth. The difference in total mRNA transcriptional activity observed in nuclei from cells of different growth rate was accounted for by the difference in transcriptional activity inhibitable by anti-myb IgG.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Inhibition of messenger RNA transcriptional activity in ML-1 human myeloblastic leukemia cell nuclei by antiserum to a c-myb-specific peptide. 354 99

Since the first discovery of antitumor properties of daunorubicin in 1962, several hundreds of anthracyclines have been evaluated. In 1969, the primary screening on L1210 leukemia allowed to detect doxorubicin which is more active than daunorubicin and has been found clinically active on several human solid tumors. Therefore, L1210 leukemia appeared to be a useful model for evaluating experimental antitumor activity of anthracyclines, indicating a possible correlation between this model and the clinic. Analogs which are equally or more active than doxorubicin in the primary screening are tested in the secondary screening, then eventually in models of cardiotoxicity in order to evaluate their therapeutic index. The secondary screening includes murine solid tumors (B16 melanoma, Lewis lung carcinoma, mammary adenocarcinomas, colon adenocarcinomas 26 and 38) and human tumor xenografts into nude mice or under the renal capsule of normal mice (LX1, lung - CX1, colon - MX1, breast). Various tumor localizations (i.p., i.v., s.c., i.m., i.c.), various routes of administration (mainly i.v. and p.o.), various schedules of treatment (early or delayed, repeated or intermittent) and models of polychemotherapy are used to obtain a better evaluation of the compound. P388 leukemia resistant to doxorubicin is useful to test cross resistance in vivo and also to screen compounds able to reverse this phenomenon. Until now, 17 new anthracyclines have been introduced into clinical trials. Aclacinomycin has a different mechanism of action from that of doxorubicin (induction of tumor cell differentiation, inhibition of B and T suppressor lymphocytes); it is less myelotoxic and it is not mutagenic in vitro. THP-doxorubicin is more active than doxorubicin against L1210 leukemia and some solid tumors; it seems less cardiotoxic.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Models of preclinical studies of anthracyclines]. 355 Jun 11

Neutral glycosphingolipids (neutral GSLs) of the human myeloid leukemia cell lines ML-2, ML-3, HL-60 and THP-1-0 were metabolically labeled with [3H]galactose and [3H]glucosamine, and analyzed by high-performance liquid chromatography. They were compared with unlabeled neutral GSLs from purified human granulocytes and monocytes. Neutral GSLs were identified by retention times and the structures were further confirmed by degradation with specific exoglycosidases. Two neutral GSLs of the globoseries, globotetraosylceramide and globotriaosylceramide were found in monocytes and the monoblastic leukemia line THP-1-0. The leukemia-derived cell-lines, ML-3 and HL-60, representing successively earlier stages of myeloid differentiation, contained respectively less neutral GSLs of the globoseries and an increasing proportion of (neo)lacto neutral GSLs. Granulocytes and the cell line ML-2 contained almost exclusively neutral GSLs of the (neo)lacto series.
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PMID:Glycosphingolipids of the globo-series are associated with the monocytic lineage of human myeloid cells. 385 98

Monoclonal antibodies were produced against surface antigens of live cells from a human acute monocytic leukaemia cell line (THP-1). One clone, VIC-C2, when assayed by immunofluorescence microscopy, brightly stained the surface of THP-1 cells and the cytoplasm of Langerhans cells, fibroblasts and melanocytes in sections of human skin. The immunoreactive cytoplasmic structures were filamentous and resembled intermediate filaments. By double immunofluorescence microscopy using VIC-C2 and polyclonal antibodies to vimentin, the VIC-C2 antigen was shown to be located on intermediate filaments of cultured fibroblasts and to follow these filaments during various drug-induced rearrangements. As demonstrated by immunoprecipitation, antibody gel overlay and immunoblotting of two-dimensional polyacrylamide gels, VIC-C2 recognized two different antigens in extracts of THP-1 cells: one of Mr = 43 000 and pI = 7, the other of Mr = 57 000. In extracts from various cultured fibroblast cells only the 57 000 Mr antigen was detected. This 57 000 Mr protein was identified as vimentin by immunoblotting of rat glioma C6 cytoskeletons on two-dimensional gels. When vimentin was digested with chymotrypsin, only fragments containing parts of both helical rod pieces and the connecting non-helical spacer-region were strongly antigenic, whereas the helical rods alone were only weakly crossreactive. Moreover, immunoprecipitation revealed that VIC-C2 preferentially reacted with native compared to denatured vimentin.
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PMID:Monoclonal antibody to a 43 000 Mr surface protein of a human leukaemia cell line (THP-1) crossreacts with the fibroblast intermediate filament protein vimentin. 386 May 6

The growth inhibitory activity of human recombinant leucocyte A interferon (Ro22-8181: alpha-interferon) against 23 human cultured cell lines derived from leukemias and lymphomas was measured quantitatively by regrowth assay. Daudi cells were the most sensitive to it. Two T-cell lines (RPMI-8402, HUT78), three B-cell lines (Raji, Ly16, A3/Kawakami), one non-T, non-B acute lymphoblastic leukemia (ALL) cell line (KOPN-1) and three myelomonocytoid cell lines (U937, THP-1, ML-1) were moderately or slightly sensitive. Although the levels of sensitivity of these cell lines were different, cells could be killed by the recombinant alpha-interferon. Morphological changes in the sensitive cells treated with it were decreases in mitosis, pyknosis and fragmentation of the cells. Thirteen other cultured cell lines were not sensitive. The results indicated that the growth inhibitory activity of recombinant alpha-interferon is not always cell lineage-specific. There were only three cell lines whose sensitivity, expressed by the concentration required for 90% growth inhibition, was less than the several hundred units per milliliter that has usually been obtained as blood levels in clinical trials. These three included one of 10 T-cell lines and two of seven B-cell lines; none of six non-T, non-B ALL and myelomonocytoid cell lines were that sensitive. Among virus-associated cell lines, only Epstein-Barr virus-associated B-cell lines were sensitive to the interferon; adult T-cell leukemia virus-associated T-cell lines were not sensitive. It was demonstrated that recombinant alpha-interferon has a time-dependent, but not a concentration-dependent cytocidal action, indicating that optimal therapeutic schedules of recombinant alpha-interferon for cancer may be daily long-term treatment, not single or short-term large-dose therapy.
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PMID:Time-dependent cytotoxic action of human recombinant alpha-interferon (Ro22-8181) in vitro and the sensitivity of various cultured leukemia and lymphoma cell lines to it. 398 16

The calcium channel blockers verapamil, diltiazem, nicardipine, and niludipine potentiated the antitumor activities of mitotic poison antitumor agents, such as vincristine, vinblastine, vindesine, VP16-213, and taxol in P388 leukemia cells resistant to vincristine. The potentiating effect was generally dependent on the extent of cross-resistance seen in the cell line for these drugs. Calcium channel blockers also potentiate the antitumor activities of several DNA-interacting drugs, such as adriamycin, THP-adriamycin, daunomycin, aclacinomycin A, mitomycin C, actinomycin D, mitoxantrone, and nogalamycin derivatives in P388 leukemia resistant to adriamycin. Greater potentiation was observed for those antitumor agents to which the ADM-resistant cell line had become markedly cross-resistant, with the exception of the nogalamycin derivatives. Only a two-fold enhancement was observed for mitomycin C and aclacinomycin, as the cell line was only weakly cross-resistant to these agents. These results suggest the potential for therapeutic gain through the use of calcium channel blockers in combination with classic chemotherapeutic agents.
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PMID:Potentiation of antitumor agents by calcium channel blockers with special reference to cross-resistance patterns. 400 44

Four human T cell lines, MT-2, TCL-Kan, TCL-As 2, and TCL-Haz, established from normal leukocytes by cocultivation with adult T-cell leukemia (ATL) virus (ATLV)-producing cells, produced constitutively phagocytosis inducing factor(s) (PIF) that induced phagocytosis in a human monocytic cell line, THP-1. These cell lines expressed ATLV-associated antigens (ATLA) as well as numerous virus particles, whereas the other twelve leukocyte cell lines tested, including T cell lines, B cell lines, and non-T and non-B cell lines, did not produce detectable amounts of the factor(s) in the culture supernatants. PIF was produced in the absence of serum and was not related to either ATLV-particles or viral structural proteins. Its activity was stable at 56 C for 30 min, but labile at 80 C for 30 min and at pH 2 for 20 hr. MT-2 and TCL-Kan produced large amounts of the factor(s) in the culture supernatants but little interferon-gamma (IFN-gamma) or colony stimulating factor (CSF) activity was detected; furthermore, the activity was not neutralized by rabbit anti-IFN-gamma sera. These observations suggest that some ATLV-transformed T cell lines produce PIF that is different from IFN-gamma and CSF.
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PMID:Constitutive production of phagocytosis inducing factor(s) in a monocyte/macrophage lineage cell line (THP-1) by retrovirus-transformed human T cell lines. 609 92

A null cell leukemia cell line, THP-5, was established from the peripheral blood of a patient with acute null cell leukemia. THP-5 cells were characterized by the presence of Ia-like antigen and the absence of other cell surface markers examined. Despite the presence of Ia like antigen, THP-5 cells had no stimulating capacity in autologous or allogeneic mixed lymphocyte reaction.
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PMID:An Ia-like antigen positive null cell leukemia cell line (THP-5) lacking in the stimulating capacity in autologous and allogeneic mixed lymphocyte reaction. 623 34


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