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Biomedical subjects

B Gibbons

Publications and source records attributed to B Gibbons.

At least 55 records · Page 3Linked to original sources

Establishment of a lymphoblastoid cell line, SD-1, expressing the p190 bcr-abl chimaeric protein.

A lymphoblastoid cell line (SD-1) has been established by Epstein-Barr virus immortalisation of Philadelphia chromosome positive acute lymphoblastic leukaemia (ALL) cells. Using newly derived anti-bcr monoclonal and anti-abl polyclonal antibodies it was demonstrated that both the original leukaemic cells and the derived cell line expressed the p190 form of the bcr-abl protein found in a proportion of cases of Philadelphia chromosome positive ALL. Interestingly, the leukaemia and the derived cell line each displayed different, clonal patterns of immunoglobulin gene rearrangements providing direct evidence that the t(9;22) translocation which results in the expression of the p190 bcr-abl protein must occur before immunoglobulin heavy chain gene rearrangement. In contrast to the leukaemia, which had multiple chromosome abnormalities in addition to the t(9;22), the cell line had the t(9;22) translocation as its sole abnormality. Although SD-1 cells were demonstrated to express continuously the p190 bcr-abl protein, they were unable to form colonies in soft agar and did not cause tumours in splenectomised nude mice. This cell line therefore represents an appropriate target cell line in which to examine the cooperativity of the p190 bcr-abl protein with other activated oncogene products.

Animals↗

Near haploid acute lymphoblastic leukemia: seven new cases and a review of the literature.

Seven new cases are described of near haploid acute lymphoblastic leukemia (ALL) and the findings reviewed together with updated complete remission duration and survival data for the 21 cases already published. The patients were four males and three females, with an age range 2-19 years; all had an immunophenotype consistent with common ALL. The poor prognostic outlook for patients with near haploid ALL is confirmed by the median remission duration of 14 months for these patients, which is comparable to that for the previously published cases. The pattern of chromosome loss was marked particularly by the presence of two copies of chromosomes 10, 14, 18, 21 and both sex chromosomes. Populations of hyperdiploid cells with double the near haploid number were observed in six of the patients, one of whom demonstrated further clonal evolution, and it is proposed that some cases classified as hyperdiploid ALL with greater than 50 chromosomes may also have arisen from a near haploid stem line.

Adolescent↗

Monosomy 20: a nonrandom finding in childhood acute lymphoblastic leukemia.

We describe four cases of childhood acute lymphoblastic leukemia with monosomy 20 as the sole cytogenetic abnormality. These cases represent 3.4% of cytogenetically abnormal childhood ALL studied in our institute at diagnosis. The patients presented at similar age, ranging from 31 to 36 months. All four patients remain in first remission with survival time being at least 20 months from the time of diagnosis.

Antigens, CD↗

Infant acute lymphoblastic leukaemia with t(11; 19).

Seven cases of infant acute lymphoblastic leukaemia with t(11; 19) (q23; p13) are described. They are characterized by a high white cell count, organomegaly, early central nervous system (CNS) disease, and a poor prognosis. Blasts are usually of an immature early B-cell lineage although monocytoid features are present in some cases. The characteristics of infant acute leukaemia with t(11; 19) are very similar to those found with t(4; 11), and the presence of t(11; 19) may indicate the same poor prognosis.

Antigens, Neoplasm↗

The use of DNA probes to monitor minimal residual disease in childhood acute lymphoblastic leukaemia.

DNA probes to both the joining region (JH) of the immunoglobulin heavy chain gene (IgH) and to the beta chain of the T-cell antigen receptor complex (TCR) have been used as tumour-specific markers to monitor the rearrangements of the IgH chain gene and the TCR beta gene in the blast cells of children presenting with acute lymphoblastic leukaemia (ALL) of B or T cell origin. Blast cells from 68 children with early B cell ALL and eight with T-ALL were examined at presentation, at day 28 after commencement of therapy and at varying times thereafter. An additional 43 patients (42 with B cell ALL, one with T-ALL) were studied both at presentation, at completion of their 2-year treatment course and 3 months later. Twelve patients, drawn from both these groups, were studied at relapse as were a further eight patients in whom an extramedullary relapse had occurred. Persistence of clonally-derived cells as a predictor of early relapse was seen in the day 28 bone marrows of 11/76 newly-diagnosed children (nine early B and two T-ALL) followed by rapid, overt relapse in four of the early B ALL cases. No minimal residual disease (MRD) was detected in bone marrows from any of the 43 patients completing their 2-year treatment course, but six of these subsequently relapsed at varying time periods thereafter. Identical patterns of rearrangement at both presentation and relapse were seen in most cases. Oligoclonality, or multiple IgH chain gene rearrangements was seen in the blast cells of 15% of patients with early B cell ALL. No correlation between oligoclonality, high white count, unfavourable phenotype or abnormal karyotype could, however, be ascertained.

Antigens, Neoplasm↗

Three infants having null acute lymphoblastic leukemia with chromosome rearrangements at 11q23: no involvement of a heritable fragile site in this band.

Three families are presented in which an infant with null acute lymphoblastic leukemia had a karyotype rearrangement involving a break at 11q23. Peripheral blood was obtained, where possible, from both parents and from the child during periods of remission. The blood was stimulated with phytohemagglutinin and cultured under conditions that enhance expression of heritable folate-sensitive fragile sites. In all individuals studied very low levels of fra(11)(q23.3) were observed. These levels were far below those recorded for expression of the heritable folate-sensitive site fra(11)(q23.3) but are comparable with expression of the common fragile site fra(11)(q23.3) under these conditions.

Chromosome Banding↗

Rearrangement of T-cell receptor and immunoglobulin heavy chain genes in childhood acute mixed lineage leukaemia.

Rearrangement of the beta and gamma chain genes of the TCR gene complex and of the Ig heavy chain genes were examined in three cases of childhood acute mixed lineage leukaemia. Blast cells, classified morphologically as acute lymphoblastic leukaemia (ALL) in one child and acute non-lymphocytic leukaemia (ANLL) in the other two, all co-expressed markers associated with both T (CD7, TdT) and myeloid (CD33) cells. Cytogenetic analysis detected abnormalities associated with myeloid leukaemia. Immunoglobulin heavy chain genes were not rearranged in two patients but a novel rearrangement was seen in the third. No rearrangement of the beta or gamma chains of the T-cell receptor complex were seen. Acute mixed lineage leukaemia may thus arise from a pluripotent precursor cell capable of both lymphoid and myeloid differentiation.

Antigens, Differentiation↗

Childhood monosomy 7 revisited.

Monosomy 7 is found in acute myeloid leukaemia (AML) and myelodysplasia and is characteristic of a rare chronic myeloproliferative disease (MPD) of young children. We have seen 16 children with monosomy 7. Their clinical features and response to treatment are discussed. Monosomy 7 diseases appear to have a particularly poor prognosis. The AML is often resistant to treatment and relapse is common. Children with chronic MPD die of bone marrow failure or evolve to AML or myelofibrosis. We have treated these children intensively with combination chemotherapy and allogeneic bone marrow transplantation. Four children with MPD received supportive care and low dose chemotherapy alone. They all died, surviving between 4 months and 4 years. Six children with MPD received intensive chemotherapy: three remitted, one relapsing after 9 months, the others remaining in remission at 18 months and 3 years. One child with MPD has undergone successful BMT and survives 7 1/2 years after presentation. Remission was achieved in three of four cases of AML. They all relapsed within 9 months. Bone marrow transplantation was successful in one child with myelofibrosis. Intensive chemotherapy and early bone marrow transplantation is likely to offer these children their best chance of survival.

Antineoplastic Combined Chemotherapy Protocols↗

Cellular and molecular studies on infant null acute lymphoblastic leukemia.

We have studied the cellular and molecular basis of eight cases of infant null acute lymphoblastic leukemia (ALL). All eight patients were under 9 months of age and presented with leukocyte counts in excess of 60 X 10(9)/L, organomegaly, and in two cases CNS infiltration. Although seven cases were morphologically classified as ALL, one patient had both lymphoid and myeloid features. Phenotypic analysis of leukemic blasts from all patients showed a typical null ALL pattern, ie, CD10 (common ALL antigen)-negative, strongly HLA-DR-positive, and CD19 (B4)-positive. The presence of terminal deoxynucleotidyl transferase (TdT) at presentation was positive in six patients' cells and negative in two. Two patients also expressed the myeloid-associated markers CD33 (MY9) and CD15 (TG1), and coexpression of CD19 and CD33 was confirmed in these two by using dual marker flow cytometry (fluorescence-activated cell sorting). Electron microscopic examination of the same two patients' cells showed the presence of monocytoid blasts that labeled with the pan-B cell antibody B4 (CD19). Short-term culture of one of these patients cells in the presence of phorbol ester resulted in the majority of the cells exhibiting myeloid markers, strong nonspecific esterase positivity, and phagocytic properties. Cytogenetic analysis showed the common feature in 7 of 8 cases to be a break in band 11q23. Molecular analysis of DNA from the blast cells of all eight patients showed rearrangement of the immunoglobulin heavy-chain genes in all cases without, however, any evidence of kappa light-chain rearrangement. T cell receptor genes were present in the germline configuration in all cases. Rearrangements of the c-ets 1 oncogene, which maps to band 11q23, were not detected, thus providing no evidence for involvement of this oncogene in the common disease process. Our data indicate that although infant null ALL may present as a heterogeneous disease the similarity of many features between cases suggests a common derivation from a precursor cell sharing phenotypic and genotypic features of both B and myeloid progenitor cells.

Antigens, Neoplasm↗

Duplication of one of the products of the t(8;21) translocation in a patient with refractory anemia with excess blasts in transformation.

A 34-year-old man with refractory anemia with excess blasts in transformation is reported, having a t(8;21) translocation and a duplication of one of the products, der(21). The duplicated product had not been observed at presentation in malignant disease, as far as we are aware; thus, the findings are discussed with regard to this case and other possible smoldering leukemias. The diagnostic use of cytogenetics is also considered.

Adult↗

Subtle abnormalities in the short arm of chromosome 11 in acute myeloid leukemia.

A series of four patients with small deletions of the short arm of chromosome #11 is presented. In two of these patients, deletion of 11p was the sole karyotypic abnormality. When compared with similar reported cases an association with FAB type M4 is apparent. Such cases may often be undocumented, because the deletions can be subtle. One patient with erythroleukemia shows an inversion of chromosome #11 involving band 11p15. Because the patients' fetal hemoglobin (HbF) became raised during the course of the disease, it is postulated that the hemoglobin beta chain gene at 11p15 may have been disrupted.

Adolescent↗

Chromosomes in retinoblastoma patients.

In a series of eight patients with retinoblastoma, one was found to have a reciprocal translocation of chromosomes 1 and 13. The breakpoint on chromosome 13 is at band q12, which suggests that the retinoblastoma locus is less distal than previously thought.

Chromosomes, Human, 1-3↗

Acute myelogenous leukemia (AML) and diabetes insipidus (DI): further association with monosomy 7.

Diabetes insipidus (DI) is a rare complication of acute myelogenous leukemia (AML). Five of the six such cases described in the literature who had banded chromosomal studies performed had monosomy 7 and the sixth patient had del(7)(q22). A further case of AML complicated by DI in whom banded chromosomal studies revealed a complex karyotypic abnormality, including monosomy 7, is reported. The association between monosomy 7 and DI in AML appears specific but the reason for this association remains unclear.

Chromosomes, Human, Pair 7↗

Novel chimaeric protein expressed in Philadelphia positive acute lymphoblastic leukaemia.

Cytogenic changes are becoming increasingly important in understanding the pathogenesis of human malignancies. The t(9;22) (q34;q11) translocation is one of the most consistent and generates the Philadelphia chromosome (Ph1) (ref. 1) in chronic myeloid leukaemia (CML); it has also been observed in some acute lymphoblastic leukaemias (ALL) (ref. 2). In CML the breakpoints occur on chromosome 22 in the region designated bcr (ref. 3) and result in the expression of a bcr-abl fusion product of relative molecular mass (MT) 210,000 (210K) with associated in vitro tyrosine kinase activity (P210bcr-abl). In some cases of Ph1-positive ALL, a novel abl-related protein (P190all-abl) of 190K has been shown to have tyrosine kinase activity. In this report we demonstrate that the P190all-abl protein has a bcr determinant from the amino-terminal region, but is lacking a bcr determinant normally found in the P210bcr-abl near the bcr-abl junction. The chimaeric nature of the P190all-abl was confirmed by sequential immunoprecipitation with antisera against abl and bcr peptides.

Cell Line↗

Partners in distance learning. Project outreach.

Distance learning refers to any educational experience in which the instructor (teacher) is separated from the student (learner) by geographic distance. Partnerships are being established between institutions of higher education and healthcare organizations to achieve a mutual goal, that of educating employees to work in a rapidly changing workplace environment. The authors describe one such partnership and the common issues confronted by both the academic and service institutions in implementing an outreach education program. The authors propose that these partnerships can be effective in implementing distance learning programs that meet the ongoing educational needs of nurses living and working in rural and underserved environments.

Adult↗