Biomedical subjects

M D Minden

Publications and source records attributed to M D Minden.

At least 91 records · Page 5Linked to original sources

PubMed1991

Interactions between retinoic acid and colony-stimulating factors affecting the blast cells of acute myeloblastic leukemia.

The responses to retinoic acid (RA) of acute myeloblastic leukemia (AML) blasts and normal hemopoietic progenitors was examined under defined growth factor conditions. For the leukemic cells marked patient to patient variation was seen; blast colony formation by cells from some patients was stimulated by RA without growth factors or in the presence of recombinant granulocyte colony-simulating factor (rG-CSF), recombinant granulocyte-macrophage-CSF rGM-CSF and recombinant interleukin-3 (rIL-3); for other populations inhibition was observed under the same conditions. Some blast cells were stimulated by RA in the presence of rGM-CSF and rIL-3 and inhibited when cultured with RA and rG-CSF. Supernatants prepared from blasts cultured with RA and growth factors did not show activities that were not readily explained by the carry-over of growth factors; this result did not provide evidence that RA and growth factors interact to produce factors. Titrations of RA showed that activity was first observed at concentrations of 10(-9) M and was maximum at concentrations of 10(-7) M. Different effects of RA in combination with rG-CSF compared with rGM-CSF or IL-3 were not seen when the cells were tested in suspension culture rather than in methylcellulose, a finding that may be interpreted to mean that the interaction between RA and factors affects terminally-dividing blast cells. Three normal bone marrow samples were cultured with RA and growth factors. Colony formation was stimulated by RA in the presence of rGM-CSF or rIL-3 but inhibited by RA with rG-CSF. Thus a differential effect of RA in combination with growth factors occurs in normal hemopoietic cells and persists in some AML populations.

Bone Marrow↗

PubMed1990

Cutaneous and mucosal neoplasms in bone marrow transplant recipients.

Fifty-six long-term survivors of bone marrow allografts were followed for a minimum of 40 months after bone marrow transplantation (BMT) to determine the frequency of secondary malignancies. The 56 patients included ten with severe aplastic anemia (SAA), 16 with acute myeloblastic leukemia (AML), 11 with acute lymphoblastic leukemia (ALL), and 19 with chronic myelogenous leukemia (CML). All patients received a preparative regimen combining high-dose chemotherapy with total body irradiation (TBI). Three patients developed a malignancy of the skin or oral mucosa. Two were diagnosed as squamous cell carcinoma and one as a malignant melanoma. All three patients had chronic graft versus host disease (GvHD) and were treated for prolonged periods with immunosuppressive medications. The lesions of all patients developed in areas involved by chronic GvHD.

Adult↗

PubMed1990

The effects of leukemia inhibitory factor (LIF) on the blast stem cells of acute myeloblastic leukemia.

Leukemia inhibitory factor (LIF) was tested using three established acute myelocytic leukemia (AML) cell lines. In growth assays in two of the three lines, we found that the addition of LIF increased the doubling time of the clonogenic population but not the total population as assessed by nucleated cell counts. Similarly, tritiated thymidine uptake into total AML populations was not affected by LIF, but the percentage of clonogenic cells killed by exposure to high specific activity 3HTdR was reduced in LIF-treated cultures compared to controls. We interpret these results to indicate that LIF prolongs the cell cycle of stem cells in some AML lines, possibly by increasing the time spent in the G2-M-G1 parts of the cycle. Consistent with this interpretation, we observed a decrease in ara-C sensitivity in LiF treated cultures. Variable results were obtained when freshly obtained AML blasts were exposed to LIF.

Cell Cycle↗

PubMed1990

The influence of growth regulation on treatment strategy for acute myeloblastic leukaemia.

Acute myeloblastic leukaemia (AML) is a useful model for generalized malignant disease. Haemopoiesis in AML is clonal; a characteristic cell population (blast cells) has been identified and can be grown in culture. The population is organized as a hierarchy, headed by self-renewing stem cells. Several control mechanisms affect the behaviour of these stem cells. Two classes of regulatory receptors are identified that act by ligand-receptor interaction; in one class the receptors are intracellular, in the other they are in the cell membrane. It is proposed that the many regulatory signals received by blast cells contribute to a genetically determined regulatory milieu that sets the probabilities of blast stem cell renewal and differentiation. Interactions have been identified between regulatory mechanisms and the responses of blast stem cells to chemotherapeutic agents. It is suggested that new therapeutic options are emerging, based on the exploitation of regulatory mechanisms in conjunction with chemotherapy.

Antineoplastic Agents↗

PubMed1989

Analysis of molecular events in leukemic cells arrested at an early stage of T-cell differentiation.

We analyzed the rearrangement and expression of T-cell receptor (TCR) genes, including the recently identified TCR delta gene, in 21 patients with T-lineage leukemia/lymphoma. Among 8 patients with CD3-, CD4-, and CD8- (group I), 2 patients showed germline configuration of the TCR delta, gamma, beta, and alpha genes and 1 patient demonstrated only TCR delta gene rearrangement. All nine patients with CD3-, CD4+, and/or CD8+ (group II) showed concomitant rearrangements of the TCR delta, gamma, and beta genes. TCR alpha gene rearrangement was also observed in two patients. Three of four patients with CD3+ (group III) showed rearrangement of the TCR alpha gene with deletion of both alleles or of a single allele of the TCR delta gene. With Northern blot analysis, full-length transcripts of the TCR delta gene were detected in 3 of 15 examined patients. All were restricted to group I or group II. In contrast, full-length transcripts of TCR beta and alpha were observed mainly in samples from groups II and III. Based on these findings, rearrangement of the TCR delta gene may be the earliest event in T-cell differentiation, preceding rearrangements of the other TCR genes.

Antigens, CD↗

PubMed1989

T cell receptor delta gene organization and expression in normal and leukemic natural killer cells.

In peripheral blood most NK activity is mediated by CD3- cells with large granular lymphocyte morphology which cannot be assigned to a specific hemopoietic lineage. In accordance with previous studies we have analyzed the organization of the TCR delta gene, which rearranges early in thymic ontogeny, in normal NK cells, and in granular lymphocytes proliferative disorders (GLPD), in an effort to further define their relationship to the T cell differentiation pathway and to identify a possible marker of clonality for CD3- GLPD. The alpha/delta locus was rearranged in five cases of CD3+ GLPD with a biallelic deletion of the C delta region, suggesting V-J alpha rearrangement, whereas CD3- GLPD and normal CD3- NK cells had the delta gene in germ-line configuration, but surprisingly expressed high levels of TCR delta-related mRNA. On the basis of this finding and of the presence of truncated TCR-beta and CD3-epsilon mRNA, we are led to speculate on a possible ontogenic relationship of NK cells to the T cell differentiation pathway at stages preceding TCR gene rearrangement.

Antigens, Differentiation, T-Lymphocyte↗

PubMed1989

Production of growth factors by malignant lymphoma cell lines.

Fourteen Epstein-Barr virus (EBV)-negative cell lines were raised from bone marrow (BM), peripheral blood (PB), or lymph node samples of patients with intermediate- or high-grade malignant lymphoma. The cell lines were propagated in liquid suspension culture. They contain clonogenic progenitors capable of forming lymphoma colonies in semi-solid culture medium. Cells of these lines were used to examine the growth factor requirements of their clonogenic progenitors and to assess their ability to produce their own growth factors. Two of the cell lines (OCI-Ly9 and OCI-Ly13.1) required addition of exogenous factors for colony growth. These factors were routinely provided by media conditioned by phytohemagglutinin-stimulated leukocytes (PHA-LCM). Three lines formed some and nine lines gave rise to optimal numbers of colonies without addition of growth factors. Eight of these factor-independent lines were able to function as feeder cells and promoted colony formation by both factor-dependent lines. Cell lines that displayed feeder cell function released activities into supernatants able to replace their cellular source. Some of these endogenously produced growth-promoting activities could be replaced by known hematopoietic growth factors. Both factor-dependent cell lines were cultured with recombinant IL-1 alpha, IL-2, IL-3, IL-6, and GM colony-stimulating factor (CSF) and semipurified B-cell growth factor (BCGF) interleukin-4 (IL-4). A heterogeneous response pattern was observed. Both lines formed colonies with IL-4. The colonies were comparable in frequency and size with colonies observed with (PHA-LCM). OCI-Ly9 responded to IL-6 but showed no growth with IL-2. In contrast, the TAC-positive line OCI-Ly13.1 gave rise to colonies with IL-2 while remaining unresponsive to IL-6. A moderate number of colonies was observed when cells of this line were cultured with GM-CSF. Colony formation of both lines was uninfluenced by IL1 alpha or IL-3.

Cell Division↗

PubMed1989

A possible autocrine role for interleukin-6 in two lymphoma cell lines.

Interleukin-6 (IL-6) is a growth factor with diverse biologic activity. Originally described as a T-cell product that enhances immunoglobulin (Ig) secretion in antigen-stimulated B cells, it also affects the growth of T cells, plasmacytomas, hybridomas, and hematopoietic stem cells. We report the expression and secretion of IL-6 by two lymphoma cell lines, OCI-LY3 and OCI-LY12. Addition of recombinant IL-6 stimulated their growth, whereas addition of polyclonal anti-recombinant IL-6 (anti-rIL-6) had a marked inhibitory effect on proliferation. These results suggest an autocrine role for IL-6 in the growth of these lymphoma cells in culture.

Blotting, Northern↗

PubMed1989

The T-cell receptor delta chain locus is disrupted in the T-ALL associated t(11;14)(p13;q11) translocation.

Two T-ALL patients carrying a t(11;14)(p13;q11) translocation were analyzed. Southern blotting experiments demonstrated that both patients had rearranged their J delta genes and that the translocation involved the delta locus in both cases. In one patient, cloning, restriction mapping, and sequencing showed that the translocation occurred on a D delta 1-D delta 2-J delta 2 rearranged gene. In addition, the rearrangement on chromosome 11 occurred in both patients within a segment of less than or equal to 2 kb showing the presence in this region of a point of recurrent recombination.

Base Sequence↗

PubMed1989

EBV and HSV infections in a patient who had undergone bone marrow transplantation: oral manifestations and diagnosis by in situ nucleic acid hybridization.

The course of infections with herpes simplex virus and Epstein-Barr virus in an immunosuppressed patient who had undergone bone marrow transplantation and had tested seronegative for human immunodeficiency virus is described. The clinical oral manifestations were unusual, as they included hairy leukoplakia-like lesions and extensive mucosal ulceration. Histologic examination disclosed unique features consisting of both lichenoid and viral cytopathic changes. The association of the lesions with both Epstein-Barr virus and herpes simplex virus was confirmed by in situ hybridization histochemistry. The importance of recognition of the symptoms, specific diagnosis by DNA hybridization, and implications for antiviral prophylaxis and therapy are emphasized.

Adult↗

PubMed1989

The expression of the proto-oncogene C-kit in the blast cells of acute myeloblastic leukemia.

The oncogene kit has been shown genetically to map in the W locus of the mouse. This locus is known to have an important role in the regulation of normal hemopoietic stem cell growth. The blast cells of acute myeloblastic leukemia may be considered to arise in predeterministic stem cells. Accordingly, we sought evidence that kit was involved in the regulation of AML blast growth, using a cDNA probe to the external domain of c-kit. With this probe the gene was found to be in germline configuration in blast cells from AML, ALL, and continuous myeloblastic cell lines. However, expression could be detected by Northern analysis or RNA dot blots only in fresh AML blast cells. Fresh cells from ALL patients, normal bone marrow, PHA-stimulated lymphocytes, and four myeloblastic continuous cell lines were expression negative by the same techniques.

DNA↗

PubMed1989

T-cell receptor delta gene rearrangement in childhood T-cell acute lymphoblastic leukemia.

During the development of functional T lymphocytes, a variety of genes involved in antigen recognition undergo somatic rearrangement. These include the alpha, beta, and gamma chain genes. Recently a fourth rearranging gene, the delta chain gene, embedded in the alpha chain locus, has been described. We have determined the structure of the beta, gamma, and delta chain genes in 15 cases of T-cell acute lymphoblastic leukemia (T-ALL) representing stage I (CD7+, CD1-, CD3-) and stage II (CD7+, CD1+, CD3-) of intrathymic T-cell development. The alpha-delta locus was rearranged in 14 of the 15 cases. In three cases the delta constant region was deleted on both chromosomes, suggesting biallelic V-J alpha rearrangement. A limited pattern of rearrangement of the delta locus was observed in the remaining 11 cases. When the alpha-delta region was rearranged, there was rearrangement of the beta and gamma TcR in all cases except two; in these cases the beta chain was in the germline configuration. These findings support the hypothesis that delta chain gene rearrangement is an early event in T-cell development, possibly contemporary to gamma gene rearrangement, and that the delta locus has a limited repertoire.

Gene Rearrangement, T-Lymphocyte↗

PubMed1989

Expression of a retinoic acid receptor gene in myeloid leukemia cells.

Retinoic acid (RA) has been shown to increase differentiation in some leukemia cell lines (HL-60 and KG-1) but not others (K562). Similarly, RA has been reported to have variable effects on fresh blast cells. Recently, molecular clones have been obtained for the nuclear receptor for retinoic acid. The experiments described in this paper were designed to compare expression of the receptor to biological activity in myeloblastic leukemia cells. In four continuous AML cell lines, a positive correlation was found between retinoic acid receptor (RAR) expression by Northern analysis or RNA dot blot and the ability of RA to inhibit colony formation. Kinetic studies of the most sensitive cell line showed that inhibition of colony formation was associated with reduced blast cell self-renewal and differentiation-like events. RAR was detected in freshly obtained blast cells from 23 AML patients. Patient-to-patient variation was observed; however, a correlation was not found between RAR expression and response of the freshly obtained blast cells to RA.

Carrier Proteins↗

PubMed1989

Restriction fragment length polymorphism analysis of hematopoietic cells following successful treatment of relapsed acute lymphoblastic leukemia following bone marrow transplantation.

Despite aggressive therapy for leukemia in the form of bone marrow transplantation (BMT) relapse occurs in a significant number of cases. The origin of the leukemic relapse, whether it is of donor or recipient origin, and how best to treat the patients continue to pose problems for the clinician. In this paper we present a case in which the cytogenetics suggested that the relapse was of donor origin; however, molecular analysis revealed that the leukemic population was of host origin. The leukemic relapse following the BMT was treated with a second BMT. This resulted in a remission of 28 months after which leukemic relapse was again diagnosed. Using conventional chemotherapy it was possible to obtain another complete remission. This case illustrates a pitfall to cytogenetic analysis and two contrasting methods of dealing with leukemic relapse following BMT.

Adult↗

PubMed1988

Structure and rearrangement of the T cell receptor J alpha locus in T cells and leukemic T cell lines.

The vast majority of T cells express an antigen receptor (TcR) composed of an alpha/beta heterodimer. The alpha and beta chains are encoded for by a set of variable (V), joining (J) and constant (C) region genes. Unlike the J genes of the beta chain which are limited in number and are clustered close to the constant region, the J alpha genes are spread over an 85-kilobase DNA region, upstream of the C alpha gene. We have isolated the complete J alpha locus, bounded on the 5' side by the C sequence of the delta gene and on the 3' side by the C sequence of the alpha gene. The experiments described here demonstrate that the J gene segments extend 75 kb 5' of C alpha and participate equally in generating the diversity of the alpha chain in peripheral T cells. Similarly, in leukemic T cell lines, rearrangements occurred over the entire locus and involved both alleles. Densitometry data suggest that in most peripheral T cells both alleles also are rearranged; thus, allelic exclusion in the alpha locus does not occur at the level of rearrangement. In three cell lines, an identical rearrangement has occurred on one allele in a region located 10 kb from the 5' end of the locus.

Genes↗

PubMed1988

The effects of recombinant CSF-1 on the blast cells of acute myeloblastic leukemia in suspension culture.

Recombinant hemopoietic colony-stimulating factors (CSFs), including GM-CSF, G-CSF and IL-3, have been shown to be effective stimulators of both self-renewal and terminal differentiation of blast stem cells in acute myeloblastic leukemia (AML). We have examined the activity of a fourth growth factor, recombinant CSF-1 (or M-CSF), on the growth of leukemic blasts in culture. CSF-1 was found to be active on some, but not all, blast populations. In sensitive cells, CSF-1 often stimulated the production of adherent blast cells incapable of division. This observation leads us to suggest that CSF-1 may be useful in the treatment of selected cases of AML.

Adult↗

PubMed1988

Expression of the CSF-1 gene in the blast cells of acute myeloblastic leukemia: association with reduced growth capacity.

Myelopoietic growth factors are known to influence the growth in culture of malignant blast cells from human Acute Myeloblastic Leukemia (AML). We have used cDNA clones for the factor CSF-1 and its receptor fms to study DNA and RNA from the blasts of 25 AML patients. The CSF-1 gene was always in the germline configuration. CSF-1 mRNA was found in about half the blast populations. The cells were also studied for their growth properties in culture. A highly significant association was found between CSF-1 expression and poor growth in suspension culture. Most blast populations expressed fms; the number of fms expression negative samples was to small to permit the detection of any association between fms expression and growth or any interaction between the effects of the expression of the growth factor and its receptor. We propose that CSF-1 may be an important part of the mechanism determining the balance between self-renewal and determination in AML blast clones.

Blast Crisis↗

PubMed1988

Stem cell renewal and differentiation in acute myeloblastic leukaemia.

The defining properties of stem cells are capacities for self-renewal and, after determination, a limited number of terminal divisions. The blast cells of acute myeloblastic leukaemia (AML) are maintained by stem cells with these two properties. Since renewal and differentiation can be assessed separately in cultures of AML blasts, these cancer cells provide a useful model for examining stem regulation; such studies have practical importance for future developments in the treatment of AML. This paper considers three aspects of blast cell biology. First, evidence is presented that self-renewal and differentiation are regulated by specific genes; further, the DNA encoding these genes has structural features that affect the chemosensitivity of self-renewal. This sensitivity varies from patient-to-patient and is an important attribute contributing to variation in treatment efficacy. Second, the effects of myelopoietic growth factors on blast stem cells are presented and discussed, as these bear on the regulation of the balance between renewal and differentiation. Finally, models of leukaemic haemopoiesis are considered in light of the experimental findings. The suggestion is advanced that leukaemia can be explained better by abnormalities of gene expression than by blocked differentiation.

Antineoplastic Agents↗