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D C Arthur

Publications and source records attributed to D C Arthur.

At least 73 records · Page 4Linked to original sources
PubMed1989

Mature T-lineage leukemia with growth factor-induced multilineage differentiation.

We report an acute T-lymphoblastic leukemia with a predominantly mature CD3+ CD7+ WT31+ phenotype that was induced to differentiate into different cell lineages by various recombinant human growth factors. In the presence of IL-3 or GM-CSF, the leukemic cells gave rise to myeloid and monocytic cells including terminally differentiated, partially functional, segmented neutrophilic granulocytes as assessed by morphologic, cytochemical, immunophenotypic, and functional criteria. In the presence of IL-2, leukemic granulated lymphoid cells exhibiting MHC-unrestricted cytotoxicity and expressing a CD2+ CD3+ CD5+ CD7+ CD8+ CD33+ WT31+ Leu19+ phenotype arose. Leukemic cell cultures initiated with IL-3 yielded growth factor-independent cells with a mixed lineage phenotype and morphologic and cytochemical evidence of immature blasts. These were T lymphocyte and myeloid surface antigen (CD2,CD3,CD5,CD7,CD13,CD33,WT31) positive. Identical rearrangements of the constant region of the TCR-delta gene and of the joining regions of the TCR-beta, -gamma, and -delta genes were observed in the fresh and all cultured leukemic cells, indicating that they were derived from the same malignant clone. Consistent with the molecular genetic data, the cytogenetic analyses of the GM-CSF-, IL-3-cultured and the growth factor-independent leukemic cells showed the presence of multiple, closely related abnormal clones, all of which had an interstitial deletion of part of the long arm of chromosome 6 and a complex 1;10;12 translocation. In conclusion, these data demonstrate the involvement of a multipotent leukemic precursor cell in this predominantly mature CD2+ CD3+ CD5+ CD7+ WT31+ T-ALL. This multipotent leukemic precursor may be susceptible to various growth factors and respond with ordered differentiation and maturation.

Adult↗
PubMed1989

Establishment of a leukemic cell model for studying human pre-B to B cell differentiation.

Reproducible models for examining early stages of human B cell differentiation are poorly developed. We now describe the establishment and characterization of a novel human leukemic cell line that recapitulates the pre-B to B cell stage of differentiation. This cell line, designated BLIN-1, was initially established in tissue culture medium containing low m.w. B cell growth factor, and consistently shows a dependency on this cytokine for optimal growth at low density. BLIN-1 cells have a 9p chromosomal abnormality, identical to the abnormality present in the leukemic blasts from the patient's original bone marrow aspirate. The immunologic phenotype of BLIN-1 is consistent with a cell arrested at the pre-B cell stage of development. Analysis of Ig gene rearrangement and Ig expression in a series of BLIN-1 subclones show that the cells spontaneously rearrange kappa light chain genes, leading to the differentiation of surface kappa-negative pre-B cells into surface kappa-positive B cells. The BLIN-1 cell line is, to our knowledge, the first defined human model for examining this critical developmental stage in human B cell ontogeny. As such, it offers a unique resource for examining variables influencing onset of kappa L chain gene rearrangement and expression.

B-Lymphocytes↗
PubMed1989

Four new recurring translocations in non-Hodgkin lymphoma.

The identification of recurring chromosomal translocations has provided clues to the gene regions important in lymphoma development. Among 157 patients with non-Hodgkin lymphoma studied by cytogenetic analysis, four new recurring translocations have been identified--t(8;9) (q24;p13), t(11;18)(q21;q21), t(14,15)(q32;q15), and an unbalanced translocation giving rise to der(22)t(17;22) (q11;p11). Each translocation appeared twice. The t(11;18) was the only karyotypic abnormality in the two patients with it, and the t(14;15) was the sole karyotypic abnormality in one patient. All translocations were found in B-cell malignancies and were associated with both nodal and extranodal disease. Among the regions affected, only the immunoglobulin heavy-chain gene MYC, and BCL2, have thus far been associated with lymphoma. The breakpoint sites identified by these translocations warrant further investigation at the molecular level.

Aged↗
PubMed1988

Systemic polyclonal immunoblastic proliferations.

This report describes the clinical and pathologic features of four patients with a florid, systemic immunoblastic proliferation. The blood of these patients exhibited a mild to marked leukocytosis with a high percentage of immunoblasts and plasma cells. The bone marrow also was infiltrated extensively by immunoblasts. Lymph node biopsy specimens from two patients showed near total effacement of the nodal architecture by a diffuse infiltration of immunoblasts and plasma cells. The proliferative process was determined to be polyclonal with immunohistochemical techniques. Cytogenetic studies of bone marrow from two patients showed a pseudodiploid abnormal clone, with a translocation involving a break in band 14q32 in each case. The pathogenesis of these proliferative disorders in unclear, although three patients had some evidence of an acute immune disorder. One of these patients was treated with steroids, vincristine, and cyclophosphamide. Another patient was treated with steroids only, and one patient was treated with steroids and cyclophosphamide. All had rapid regression of the disease process. Two patients are alive and apparently free of disease 31 and 48 months after diagnosis. One died of sepsis. The fourth patient had acquired immune deficiency syndrome (AIDS) and died without therapy. The biology of the immunoblastic proliferation of these patients is uncertain. The immunohistochemical results suggest a reactive, polyclonal proliferation, but the cytogenetic abnormalities in two patients indicate the possibility of a cryptic neoplastic clone.

Acquired Immunodeficiency Syndrome↗
PubMed1988

Cytogenetic abnormalities predict clinical outcome in non-Hodgkin lymphoma.

Tumor cytogenetic analysis was done for 68 patients with newly diagnosed non-Hodgkin lymphoma, and recurring cytogenetic abnormalities were correlated with achievement of complete remission, duration of complete remission, and survival. Among all patients, the presence of normal metaphases in tumor material was associated with a higher complete remission rate and longer survival. However, the duration of complete remission did not correlate with the presence or absence of chromosomal changes. Among patients with follicular lymphomas, the presence of normal metaphases in the tumor material was again associated with a higher rate of complete remission and with longer survival. Patients with structural abnormalities of chromosome 17 had a shorter survival than patients without these abnormalities. Among the patients with diffuse large-cell and immunoblastic lymphomas, those with breaks in the short arm of chromosome 2 had a longer survival than those without these breaks. We conclude that chromosomal abnormalities are predictive of clinical outcome in malignant lymphoma.

Adolescent↗
PubMed1988

Epstein-Barr virus associated B cell lymphoproliferative disorders following bone marrow transplantation.

B cell lymphoproliferative disorders (BLPD) developed in eight patients following bone marrow transplantation (BMT) for leukemia (five patients) or immunodeficiency (three patients). Recipients of T depleted marrow from a mismatched donor were at particularly high risk of this complication. Six of 25 (24%) recipients of mismatched T depleted bone marrow developed BLPD. In contrast, none of 47 matched T depleted transplants, one of ten (10%) who received non-depleted marrow from an unrelated donor, and only one of 424 matched non-depleted transplants were associated with BLPD. Epstein-Barr virus (EBV) specific serology and DNA hybridization studies demonstrating five to 50 copies of EBV genome/cell in involved tissues implicate this virus as an associated etiologic agent. Restriction fragment length polymorphism (RFLP) and cytogenetic analysis of involved tissue demonstrated donor origin (five of seven) or host origin (two of seven). Histologic appearance was similar to EBV-induced polymorphic B cell proliferations described following solid organ transplantation, or which occur de novo in primary immunodeficiency. Six of seven patients with adequate tissue available for study were found to have monoclonal proliferations by: in situ immunofluorescence (six of seven), and/or immunoglobulin gene rearrangement, (four of six). Cytogenetic analysis of involved tissues from four patients showed a normal karyotype, whereas two had multiple clonal chromosomal abnormalities. Seven patients died despite aggressive attempts at therapy with combinations of antiviral, immunologic, and chemotherapeutic agents.

Antibodies, Viral↗
PubMed1988

Immunophenotypic and cytogenetic analysis of Molt-3 and Molt-4: human T-lymphoid cell lines with rearrangement of chromosome 7.

Molt-3 and Molt-4 are T-cell lines originally derived in 1971 from a patient with T-cell acute lymphoblastic leukemia. An unusual T-cell antigen receptor gamma-chain gene (T-gamma) rearrangement detected by Southern blot analysis of Molt-4 prompted an in-depth study of the immunophenotype and karyotype of both cell lines. Molt-3 and Molt-4 had immunophenotypic characteristics of thymocytes with expression of CD1 and CD5. Both cell lines had a hypertetraploid karyotype with two rearranged no. 7 chromosomes: 2der(7)t(7;7)(p15;q11). The presence of a break in chromosome band 7p15 suggested the involvement of T gamma. We cloned the rearranged BamHI fragments spanning the known T-gamma constant and joining regions. Comparison with germline clones of T gamma did not suggest any of the clones included a breakpoint region. Thus the 7p15 chromosomal abnormality in Molt-3 and Molt-4 is not associated with the currently described joining and constant regions of T gamma.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1987

In vitro correlates of low dose ara-C efficacy: clinical, cytogenetic, and bone marrow culture analysis.

Low-dose Ara-C (10 mg/m2 subcutaneously bid) has been used as an alternative therapy for acute nonlymphocytic leukemia (ANLL) and myelodysplastic syndromes. We sought to define its therapeutic mechanism by assessing clinical and cytogenetic responses to treatment in conjunction with careful in vitro study of both morphologic and functional characteristics of bone marrow cells cultured with Ara-C. Sixteen patients (12 ANLL, four myelodysplastic syndrome) were treated. All developed pancytopenia and 11 of 12 had bone marrow hypoplasia during treatment. Four had a meaningful clinical response while five more showed in vivo leukemic cell sensitivity to low-dose Ara-C. Seven showed no response. Cells with cytogenetic abnormalities were either decreased in number or eradicated during clinical improvement. Liquid culture of marrow mononuclear cells with Ara-C (.033-.333 micrograms/ml X 7 days) produced little evidence of morphologic or functional differentiation (ten of 11 studied). No functional maturation was observed in cells from clinically responding patients. We conclude that low-dose Ara-C is modestly effective for some patients with ANLL or myelodysplasia. However, no evidence for in vivo leukemic differentiation is suggested by either in vitro culture studies or cytogenetic correlates of clinical response. In vitro marrow culture studies failed to predict clinical response to Ara-C.

Acute Disease↗
PubMed1987

Heterogeneity of cultured leukemic lymphoid progenitor cells from B cell precursor acute lymphoblastic leukemia (ALL) patients.

Colony assays were performed for 50 patients with B cell precursor acute lymphoblastic leukemia (ALL). Blast colony formation was observed for 33 patients, and the plating efficiency (PE) showed a marked interpatient variation, which indicates a pronounced biological heterogeneity at the level of leukemic progenitor cells. Notably, the mean PE of leukemic B cell precursors from patients with a pseudodiploid or near-diploid karyotype with structural chromosomal abnormalities (SCA) was significantly higher than the mean PE of normal diploid or hyperdiploid cases. All patients who had SCA involving 7p13, 11q23-24, or 12p11-13, and patients with a Philadelphia chromosome had high PE values. The S phase percentage, expression of CD19 antigen, and relapse status were also correlated with PE. Significantly, colony blasts had slightly different surface marker profiles in each case and were common ALL antigen negative in 33% of cases, which indicates the existence of a marked immunological heterogeneity at the level of leukemic progenitor cells.

Adolescent↗
PubMed1987

Hypopigmentation in the Prader-Willi syndrome.

Cutaneous and ocular pigmentation were evaluated in 29 individuals with the Prader-Willi syndrome (PWS). Criteria for hypopigmentation included the presence of type I or II skin, the lightest skin type in the family by history, and iris translucency on globe transillumination. On the basis of these criteria, 48% of the PWS individuals were hypopigmented. The presence of hypopigmentation correlated with a small interstitial deletion on the proximal long arm of chromosome 15; however, this deletion was also found in individuals who did not meet the full criteria for hypopigmentation. Hairbulb tyrosinase activity and glutathione content, as well as urine cysteinyldopa excretion, were low in PWS individuals with and without hypopigmentation and did not separate these two groups. We conclude that hypopigmentation is found in a significant proportion of individuals with PWS and that the hypopigmentation may be associated with a deletion of the long arm of chromosome 15. The mechanism for the hypopigmentation is unknown.

Chromosome Deletion↗
PubMed1986

Genetics and cytogenetics of pediatric cancers.

It is clear that genetic factors play an important role in the development of some human cancers. These factors may be particularly influential in the pediatric age group because environmental exposures have been minimal. Several pediatric solid tumors, including retinoblastoma and Wilms' tumor, are hereditary. Specific constitutional chromosome abnormalities have been found in these patients, thus implicating certain gene regions as being involved in tumorigenesis. Molecular genetic studies have provided insight into the events occurring at the DNA level in these gene regions. The role of genetics in the development of sporadic pediatric malignancies is also beginning to be elucidated as specific acquired chromosome abnormalities are being discovered in the malignant cells of these otherwise karyotypically normal individuals. This paper will review selected hereditary and nonhereditary pediatric cancers that demonstrate the importance of genetic considerations in the diagnosis and management of children with cancer.

Acute Disease↗
PubMed1986

Abnormalities of the central visual pathways in Prader-Willi syndrome associated with hypopigmentation.

Patients with oculocutaneous or ocular albinism have misrouting of optic fibers, with fibers from 20 degrees or more of the temporal retina crossing at the chiasm instead of projecting to the ipsilateral hemisphere. Misrouting can result in strabismus and nystagmus. Because patients with the Prader-Willi syndrome may also have hypopigmentation and strabismus, we wondered whether they too might have misrouting of optic fibers. We therefore studied six patients with Prader-Willi syndrome selected for a history of strabismus, using pattern-onset visually evoked potentials with binocular and monocular stimulation to look for evidence of misrouted retinal-ganglion fibers. Four had hypopigmentation, and three of these four had abnormal evoked potentials indistinguishable from those recorded in human albinos. The two with normal pigmentation had normal responses. These findings indicate that patients with Prader-Willi syndrome who have hypopigmentation have a brain abnormality characterized by misrouting of retinal-ganglion fibers at the optic chiasm--a finding previously reported only in forms of albinism.

Adult↗
PubMed1986

Cytogenetic studies of long-term survivors of childhood acute lymphoblastic leukemia: a follow-up report.

Previous series including our earlier study of survivors of childhood acute lymphoblastic leukemia have documented the presence of nonclonal chromosome abnormalities in peripheral blood lymphocytes. To investigate whether or not these abnormalities persist, we restudied nine patients, all of whom had received radiotherapy and a minimum of 3 years of systemic chemotherapy. Therapy had been discontinued a median of 3.9 years prior to study in our first report and a median of 7.2 years prior to study in this follow-up report. Thirty metaphases from short-term cultures of phytohemagglutinin-stimulated peripheral blood from each of nine patients and nine matched controls were analyzed using G-banding. Nonclonal chromosome abnormalities were present in cells from six of the nine patients and 3.0% of patients' cells overall, as compared to seven of ten patients and 3.5% of patients' cells in the earlier study. All patients studied twice had abnormalities on one or both occasions. No evidence for the development of cytogenetically abnormal clones was found. Combined data from the two evaluations indicate that all of the patients have a small population of long-lived lymphocytes with nonclonal chromosome abnormalities, the frequency of these cells appears to remain remarkably constant over time, and the proportion of cells with chromosome abnormalities is approximately threefold greater in patients than in controls. It has become apparent that survivors of acute lymphoblastic leukemia are at increased risk for development of second malignant neoplasms. The relationship between therapy-induced chromosome damage and the development of second malignant neoplasms is currently unknown. We speculate that some cells, possibly in tissues other than peripheral blood, are preneoplastic by virtue of therapy-induced chromosome rearrangements involving critical genes and, following a long latent period, may undergo subsequent genetic or cellular changes that result in malignant transformation. Unfortunately, however, estimation of genetic damage through cytogenetic studies of peripheral blood T-lymphocytes does not appear to be a useful method for prediction of second malignant neoplasms following acute lymphoblastic leukemia, since most or all of the patients have a low level of abnormal cells.

Acute Disease↗
PubMed1986

Acute megakaryoblastic leukaemia in children.

We report four children with acute megakaryoblastic leukaemia (AMKL) and compare their clinical course with 16 previously reported cases of AMKL in children. In adults, AMKL has been reported as a rapidly progressive disease characterized by pancytopenia associated with bone marrow fibrosis, absence of organomegaly, and unresponsiveness to therapy. Although some of the childhood cases present with these features, the clinical course can be quite variable, particularly in young children, with both organomegaly and leucocytosis occurring. Down syndrome, or other constitutional abnormalities of chromosome 21 were present in four of 20 reported cases. Two of the four cases reported herein were initially diagnosed cytologically as childhood acute lymphoblastic leukaemia (ALL). All four patients achieved a complete remission, and three remain in remission from 34 to 56 months from diagnosis. Greater recognition of AMKL in the future will help to clarify the disease characteristics, prognosis and optimal treatment of this unusual form of leukaemia.

Acute Disease↗
PubMed1986

Correlations between immunological phenotype and karyotype in malignant lymphoma.

We have correlated immunological characteristics and karyotypic abnormalities from lymphomas in 118 patients. T-lymphomas differed significantly from B- and non-B-, non-T-lymphomas in having more normal metaphases, trisomy 19, and breaks at 1q21, 2q21, 3q27, 4q21, and 17q21 (P less than or equal to 0.03). Non-T-lymphomas had breaks in 18q in one-half the cases, but only one of 11 T-lymphomas had such breaks (P = 0.02). Among B-lymphomas, specific chromosome abnormalities were associated with the type of immunoglobulin heavy but not light chain expressed. A break at 14q22 or q24 was associated with surface delta mu-immunoglobulin (P = 0.02); trisomy 22 or a break in 22q and a break at 2q32 was associated with surface gamma-immunoglobulin (P less than 0.001); and trisomy 12 and a break at 2p13 was associated with cytoplasmic gamma-immunoglobulin (P less than 0.01). Among B-lymphomas, several cytogenetic abnormalities were associated (P less than or equal to 0.02) with expression of CD24 or CD9 surface antigens. Lack of CD24 was associated with breaks in 2p25, 5q, and 6q21; CD9 was associated with a break at 6q15. Associations with a specific immunological phenotype were not identified for cytogenetic abnormalities involving a band to which genes encoding immunoglobulin or the T-cell receptor have been localized. Breaks were common at 14q32, the genomic site of the immunoglobulin heavy chain loci, in B-, non-B-, non-T-, and T-lymphomas. In T-lymphomas this may be because this is the site of the AKT1 oncogene. Breaks were uncommonly found at the light chain loci or the genomic sites encoding the T-cell receptor. However, the recurring breakpoints associated with T-lymphomas were commonly found on chromosomes to which genes coding for various T-cell antigens have recently been provisionally assigned.

Adolescent↗