Protooncogenes in the regulation of normal hematopoiesis. An antisense approach.
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to D Caracciolo.
Explore the source record for details and available documents.
The c-myb protooncogene is preferentially expressed in hematopoietic cells, and its encoded protein, Myb, is required for hematopoietic cell proliferation. To analyze the relative Myb dependence of normal and leukemic human hematopoietic progenitor cells, normal bone marrow cells, several types of leukemic blast cells, and 1:1 mixtures of normal and leukemic cells were cultured in the presence of c-myb sense or antisense oligodeoxynucleotides; cell viability and cloning efficiency were then assessed. c-myb sense oligomers had negligible effects on normal and leukemic cells. In contrast, c-myb antisense oligomers strongly inhibited or completely abolished clonogenic growth of a T-cell leukemia line, 78% (18 of 23) of primary acute myelogenous leukemia cases examined, and 4 of 5 primary chronic myelogenous leukemia (CML) cases in blast crisis. In three of the latter patients, polymerase chain reaction analysis of a 1:1 mixture of c-myb antisense-treated normal and CML cells revealed a complete absence of bcr-abl expression, suggesting that the CML clonogenic units had been completely eliminated from the cultures. At antisense doses that inhibited leukemic cell growth, normal hematopoietic progenitor cells survived. Thus, normal and leukemic hematopoietic cells show differential sensitivity to the toxic effects of c-myb antisense DNA. Perturbation of c-myb function with antisense oligodeoxynucleotides might eventually form the basis for a molecular approach to leukemia therapy, perhaps most immediately as ex vivo bone marrow purging agents.
The growth of the human leukemia cell line AML-193 in a serum-free medium is strictly dependent on the presence of the cytokine granulocyte-macrophage colony-stimulating factor (GM-CSF), which is one of the major regulators of the myelomonocytic lineage. At present, little is known about the mechanisms by which this growth factor transduces the signal intracellularly. The results of this study demonstrate that GM-CSF needs the operation of a Na+/H+ exchanger, which is located in the plasma membrane of almost every vertebrate cell. In fact, the GM-CSF-dependent proliferation of AML-193 cells is strongly reduced in the presence of the amiloride analog EIPA, a specific inhibitor of the Na+/H+ exchanger. When acidified, AML-193 cells are able to recover the original pHi in a Na(+)-dependent and EIPA-inhibitable way; this demonstrates for the first time the presence of the Na+/H+ exchanger in these cells. Finally, GM-CSF, at doses superimposable to those needed for triggering proliferation, induces in AML-193 cells a sustained alkalinization, which is dependent on a operating Na+/H+ exchange, as it is inhibited by EIPA. These results suggest that GM-CSF, like other growth factors in other cell systems, exerts its mitogenic activity in AML-193 cells by inducing a Na+/H+ exchanger-mediated rise in pHi.
Two novel cell lines, PC-53 and PC-53A were established from an adult ALL patient, at third relapse and in the terminal accelerated phase respectively. Both lines displayed the phenotype of B-cell precursors (CD19+, CD38+, CD20-, cytoplasmic-mu-, immunoglobulin gene rearrangement), identical to the freshly isolated blast cells. Chromosomal analysis showed a prominent 45-XX karyotype, including three marker chromosomes. No chromosome 8 abnormalities were detectable, consistently with a non-rearranged c-myc locus. Both cell lines were EBV-negative. Growth stimulation by autologous supernatant was observed for PC-53 cells during the first 4 months in culture, whereas it was much less evident for PC-53A cells. Thus, PC-53 and PC-53A cells represent a useful tool to investigate the mechanisms involved in the clonal expansion of B-cell precursors.
To determine if MYB protein is preferentially required during specific stages of normal human hematopoiesis we incubated normal marrow mononuclear cells (MNC) with c-myb antisense oligodeoxynucleotides. Treated cells were cultured in semisolid medium under conditions designed to favor the growth of specific progenitor cell types. Compared with untreated controls, granulocyte-macrophage (GM) CFU-derived colonies decreased 77% when driven by recombinant human (rH) IL-3, and 85% when stimulated by rH GM colony-stimulating factor (CSF); erythroid burst-forming unit (BFU-E)- and CFU-E-derived colonies decreased 48 and 78%, respectively. In contrast, numbers of G-CSF-stimulated granulocyte colonies derived from antisense treated MNC were unchanged from controls, though the numbers of cells composing these colonies decreased approximately 90%. Similar results were obtained when MY10+ cells were exposed to c-myb antisense oligomers. When compared with untreated controls, numbers of CFU-GM and BFU-E colonies derived from MY10+ cells were unchanged, but the numbers of cells composing these colonies were reduced approximately 75 and greater than 90%, respectively, in comparison with controls. c-myc sense and antisense oligomers were without significant effect in these assays. Using the reverse transcription-polymerase chain reaction, c-myb mRNA was detected in developing hematopoietic cells on days 0-8. At day 14 c-myb expression was no longer detectable using this technique. These results suggest that c-myb is required for proliferation of intermediate-late myeloid and erythroid progenitors, but is less important for lineage commitment and early progenitor cell amplification.
Structural abnormalities of the c-abl proto-oncogene are found in hematopoietic cells of more than 90 percent of individuals with chronic myelogenous leukemia. Therefore c-abl may be important in normal as well as malignant hematopoiesis. Normal human hematopoietic progenitor cells were exposed to three different c-abl sense or antisense oligodeoxynucleotides, and the effects on myeloid and erythroid colony formation were examined. The c-abl antisense oligodeoxynucleotides inhibited myeloid, but not erythroid, colony formation. The c-abl sense oligodeoxynucleotides and bcr sense and antisense oligodeoxynucleotides were not inhibitory in this assay. These data show that c-abl is critical in normal myelopoiesis and may explain the relatively selective expansion of leukocytes in patients with chronic myelogenous leukemia.
Recombinant human (rh) interleukin-6 (IL-6), in a dose range of 1 to 10 U/mL, was able to induce a low number of neutrophilic-granulocytic colonies in a CFU-GM clonogenic assay, using T cells and adherent cells, depleted low density marrow cells. A synergistic increase in the number of granulocytic colonies was observed when rhGM-CSF at suboptimal doses and IL-6 at effective doses were both present in the assay; the increase was only additive when either rhIL-1 alpha or rhIL-3 was used together with IL-6. To determine whether the increase in colony number reflects the interactions of these factors on the same hematopoietic progenitor target cells or, instead, represents activation of accessory cells, we analyzed the effect of IL-6 on the proliferation and differentiation of three growth factor-dependent leukemic cell lines that respond with continuous proliferation to the presence of GM-CSF and IL-3 in culture. One of the three cell lines (AML-193) showed limited proliferation in the presence of IL-6 followed by terminal differentiation after 14 days into basophilic-granulocytic-like cells. A synergistic proliferative response was observed on the same cells treated with both GM-CSF and IL-6. These data support the hypothesis that IL-6 may have a direct effect on myeloid hematopoietic progenitor cells, and that GM-CSF interacts synergistically with IL-6 by acting on the same target cells.
Unlike bone marrow progenitor cells, human myeloid progenitors isolated from peripheral blood do not form colonies in semi-solid medium in the presence of rhG-CSF, rhM-CSF or rhIL-6, but do form colonies containing neutrophils, macrophages, eosinophils, basophils or mixed neutrophilic-macrophages colonies in the presence of rhIL-3 or rhGM-CSF. Priming of blood progenitors by culturing them for several days in the presence of rhGM-CSF resulted in a dramatic increase in the frequency of cells that proliferate in response to G-CSF and IL-6 and form neutrophilic granulocytic colonies. Suspension cultures maintained in the presence of IL-3 yielded increased numbers of clonogenic cells responsive to GM-CSF and G-CSF, but not to M-CSF or IL-6. rhIL-6 did not directly stimulate colony formation of peripheral blood progenitors but did prime them to respond to G-CSF. These results are consistent with a hierarchical model of granulocytic differentiation in which circulating progenitors proceed sequentially through a programme of changing growth factor sensitivity with the following sequence: IL-3, GM-CSF, IL-6 and/or G-CSF.
Human recombinant GM-CSF (rGM-CSF) was tested on highly purified and fractionated CFU-GM subsets. The fractionation was performed with the DS1-1 monoclonal antibody (MoAb), which distinguishes early and late CFU-GM. On whole bone marrow cells, rGM-CSF had a colony-stimulating activity comparable to that of known sources of CSFs, ie, the supernatant (SN) of TPA 30-1 or 5637 cell lines, used as control. A greatly reduced activity was observed when CFU-GM were depleted of phagocytizing and E rosetting cells (colony growth of 27% as compared with control). On fractionated CFU-GM, the rGM-CSF activity was even more reduced on both early and late progenitors (18% and 6% of colony growth, respectively). However, when rGM-CSF was used together with rG-CSF at suboptimal concentrations, the colony growth reached values analogous to that of control cultures. A synergistic interaction between rGM-CSF and rG-CSF in stimulating either early or late myeloid progenitors was observed. The results suggest that the activity of rGM-CSF on CFU-GM is mainly exerted through cooperation with accessory cells. r-G-CSF is one of the factors that can synergistically cooperate with r-GM-CSF in the myelopoietic stimulation.
Among human myeloid precursors two different subpopulations can be distinguished: type-2 CFU-GM, more differentiated, reacting to the monoclonal antibody DSl-1 and type-1 CFU-GM, more immature, negative to the DSl-1. Using this monoclonal antibody, type-1 and type-2 CFU-GM were fractionated and separately grown in the presence of T-cell derived CSFs, i.e., conditioned medium of PHA-stimulated T-lymphocytes (PHA-Ly) and the supernatant of Il-2-dependent normal T-cell lines (TC-SN). The supernatants of two neoplastic non-T cell lines, TPA-30-1 and GCT, were used as control. PHA-Ly and TC-SN had a very weak activity on type-2 CFU-GM (18 and 14% of colony growth, compared to control). However, they potently stimulated type-1 CFU-GM (84 and 68.5% of colony growth, compared to control). The restricted activity of T-cell derived CSFs on early myeloid progenitors is therefore demonstrated. Our results also show that CFU-GM with different responsiveness to growth factors can be physically separated on the basis of their reactivity to monoclonal antibody DSl-1.
Human macrophage colony-stimulating factor (M-CSF or CSF-1), either in purified or in recombinant form, is able to generate macrophagic colonies in a murine bone marrow colony assay, but only stimulates small macrophagic colonies of 40-50 cells in a human bone marrow colony assay. We report here that recombinant human granulocytic/macrophage colony stimulating factor (rhGM-CSF) at concentrations in the range of picograms enhances the responsiveness of bone marrow progenitors to M-CSF activity, resulting in an increased number of macrophagic colonies of up to 300 cells. Polyclonal antiserum against M-CSF did not alter colony formation of bone marrow progenitors incubated with GM-CSF at optimal concentration (1-10 ng/ml) for these in vitro assays. Thus, GM-CSF at higher concentrations (nanogram range) can by itself, elicit macrophagic colonies, and at lower concentrations (picogram range) acts to enhance the responsiveness of these progenitors to M-CSF.
Three human leukemia cell lines (TALL-101, AML-193, and MV4-11) that require granulocyte/macrophage-colony stimulating factor (GM-CSF) for growth in a chemically defined medium were examined for their response to recombinant human (rh) cytokines. Either rh interleukin (IL)-3 or rhGM-CSF alone supported the long term growth of all three cell lines, and the two growth factors acted synergistically to stimulate the proliferation of the early T lymphoblastic leukemia (TALL-101) and of the monocytic leukemia (AML-193) cells. However, IL-3 antagonized the proliferation of the biphenotypic B-myelomonocytic leukemia (MV4-11) cells in the presence of GM-CSF when both factors were used at very low concentrations. The rh granulocyte (G)-CSF independently supported the long and short term growth of AML-193 and MV4-11, respectively, and synergized with GM-CSF in inducing proliferation of these cells. By contrast, G-CSF did not stimulate TALL-101 cell growth and antagonized the effect of GM-CSF such that proliferation was arrested. Although neither rh macrophage (M)-CSF nor rhIL-1 alpha independently promoted proliferation of the three leukemia cell lines, these cytokines were able to either up- or down-regulate the GM-CSF-dependent growth of these cells. Taken together, these data demonstrate that leukemic cells often require the synergistic action of several cytokines for optimal growth, whereas other combinations of factors may be growth-inhibitory. This raises the possibility that multiple hemopoietic growth factors sustain or control leukemic cell proliferation also in vivo. In addition, the observation the G-CSF, M-CSF, and IL-1 alpha can, in some cases, arrest cell proliferation without inducing differentiation suggests that the programs of proliferative arrest and differentiation in leukemic cells can be dissociated.
Human granulocyte colony stimulating factor (G-CSF) can support the survival and short term proliferation of the interleukin 3 (IL 3)-dependent diploid murine hemopoietic progenitor cell line 32D C13. After 8 days in the presence of 30 U/ml of G-CSF and in the absence of IL 3, the great majority of 32D C13 cells becomes positive for myeloperoxidase (a marker that appears at the promyelocytic stage of the granulocytic lineage) and progressively differentiates into lactoferrin-containing neutrophilic granulocytes. Myeloperoxidase mRNA rapidly increases after 24 to 48 hr of treatment with G-CSF, peaks at day 6 and is no longer detectable at day 9 and 12, paralleling the appearance of myeloperoxidase-positive promyelocytes and myelocytes in the culture. After 12 days, 100% of the cells terminally differentiate, and clonogenic assays in IL 3-containing semisolid media indicate that the whole population has irreversibly lost proliferative capability. By using varying concentrations of both murine IL 3 and recombinant human G-CSF, the cultures develop an heterogeneous population of cells representing all the differentiation stages of the myeloid lineage, and the relative ratios of immature proliferating precursors and terminally differentiated cells present in the cultures can be modulated by modifying the concentrations of IL 3 or recombinant human G-CSF. Isobolic curves indicate that IL 3 and G-CSF have an antagonistic effect on the proliferation of 32D C13 cells. Thus, these cells represent a simplified in vitro model of normal granulocytic differentiation whose extent may be modulated completely in the presence of serum by two well-defined growth and differentiation factors: IL 3 and G-CSF.
A human leukemia cell line (TALL-101) was established from the bone marrow of a patient with an undifferentiated acute T cell leukemia using the conditioned medium (CM) of the human T cell leukemia virus (HTLV) II-transformed human cell line J-LB1. Immunofluorescence analysis on the original leukemic cells indicated the presence of T cell markers (Leu-1, Tdt, and T11); however, the established TALL-101 cell line expressed only antigens commonly present on progenitor cells, thymocytes, and myelomonocytic cells, but not on mature T cells. A high percentage of TALL-101 cells displayed the Tac antigen which was down-regulated upon incubation in the presence of recombinant human (rH) interleukin 2 (IL 2). Interferon (IFN)-gamma induced the appearance of class II histocompatibility leukocyte antigens (HLA) and of a T cell marker (3A1), and enhanced the expression of transferrin receptors on these cells. Further evidence for a T cell lineage of the TALL-101 cell line was provided by both chromosomic and genotypic analysis showing a translocation in chromosome 14 typical of T cell leukemias, and a rearrangement of the T-beta receptor locus. The growth-promoting activity in the J-LB1-CM was identified as granulocyte-macrophage colony stimulatory factor (GM-CSF), a growth factor which stimulates proliferation of normal myelomonocytic cells and other progenitor cells, but not known to have an effect on T cells. Dose response curves of [3H]thymidine incorporation and growth indicated that TALL-101 cells were sensitive to very low concentrations of rHGM-CSF, 5 ng/ml inducing maximal proliferation in chemically defined medium. The TALL-101 cell line is strictly GM-CSF-dependent for growth: upon depletion of GM-CSF from the culture medium, the cells stop proliferating immediately and die within 1 to 2 wk. The overall data, showing that GM-CSF is able to support the growth of a highly undifferentiated T cell leukemia, strongly suggests that this factor might have similar growth promoting effects on other immature T cell leukemias, and possibly, on normal T cell progenitors.
The conditioned media of 34 human tumor cell lines were screened for the ability to induce granulocyte-macrophage colonies in vitro in bone marrow cultures, to stimulate proliferation of a murine IL-3 dependent hemopoietic cell line (32D clone 3) and to stimulate thymidine incorporation in suspension cultures of acute myelogenous leukemia cells. Twelve tumor cell lines produced factors that were active in these assays. The conditioned medium of the glioblastoma cell line U87 MG was characterized in detail and found to contain G-CSF and GM-CSF. Cloning and sequencing of the U87 MG G-CSF indicated that it was derived from G-CSF b mRNA, which encodes a protein with a deletion of 3 amino acids at residues 36-38. The gene for G-CSF was mapped to human chromosome 17 band q21, a region involved in translocations frequently found in acute promyelocytic leukemia. G-CSF (U87MG) was able to induce granulocytic differentiation of the total population of a murine IL-3 dependent cell line, 32D clone 3; this effect was antagonized by IL-3. GM-CSF (U87-MG) supported the proliferation without inducing differentiation of two growth factor-dependent leukemic cell lines, TALL 101 and AML-193.
Eight permanent cell lines were established from cells of 50 consecutive patients with childhood acute leukemia. Three cell lines required growth factor-containing conditioned media. Analysis using blocking antisera and recombinant granulocytic macrophage (GM) colony-stimulating factor (CSF) identified GM-CSF as a growth factor required to establish the latter three cell lines and necessary for their continuous proliferation in chemically defined medium. Two of the GM-CSF-dependent cell lines were derived from patients with undifferentiated T- and a biphenotypic B-myelomonocytic leukemia, which suggests that GM-CSF might maintain proliferation of leukemias originating from immature progenitor cells. Cytogenetic analysis indicated that all established leukemic cell lines were aneuploid, with six lines containing chromosomal alterations related to those observed in the leukemic cells of the patient. Two patients did not have an abnormal clone identified in the marrow but did yield an aneuploid cell line. These studies indicate that GM-CSF-dependent leukemic cell lines can be established in a fraction of childhood leukemia. These cell lines lend themselves to studies aimed at the evaluation in vitro of the role of growth factors in controlling proliferation and differentiation of leukemic cells.
Between October, 1984 and October, 1987 a study program was carried out to evaluate the efficacy of MACOP-B in the advanced stages of intermediate/high-grade malignancy non-Hodgkin's lymphomas (NHL). Thirty patients were treated at diagnosis: 14 with D-E-F histology (median age = 56.5 years) and 16 with G-H histology (median age = 46.5). Complete remission (CR) rate was 42.8% for the D-E-F subgroup and 81.2% for the G-H subgroup. Bone marrow involvement was the major adverse factor for CR achievement in patients with intermediate-grade NHL. Overall, disease stage, bulky presentation and the presence of systemic symptoms did not significantly affect response to therapy. Survival curves predict 73% of patients alive at 45 months (median follow-up = 30 mo.). No significant differences were seen between D-E-F (64%; median follow-up = 36 mo.) and the G-H patients (81%; median follow-up = 27 mo.). The disease-free survival curve for all patients in CR reached a plateau phase at 78% (median follow-up = 30 mo). MACOP-B was much less effective when employed in 10 patients at relapse; only 2 out of these 10 reached a durable CR, which persisted 51 and 27 mo. after MACOP-B. The remaining 8 patients had a partial response, followed closely by disease progression: 7 died, whereas 1 patient is still alive after salvage therapy with bone marrow transplant. Thus, MACOP-B proved to be effective in patients at diagnosis with G-H histology.(ABSTRACT TRUNCATED AT 250 WORDS)
Two patients (aged 52 and 44) received high-dose sequential chemotherapy followed by myeloablative therapy and autotransplantation as first line treatment of a stage III multiple myeloma with high plasmacell labelling index. Autograft was performed with peripheral blood cells collected after high-dose etoposide followed by rhGM-CSF continuous infusion. During this period very high numbers of circulating hemopoietic progenitors were detected in both patients. Prompt, complete and durable hematological recovery was observed after autograft with peripheral blood stem cells. Thus, we conclude that massively released progenitors after high-dose chemotherapy and rhGM-CSF include stem cells capable of marrow reconstitution.