Immunoglobulin chain gene rearrangements in a t(4;11) acute leukaemia with monocytoid blasts

Phenotype, genotype and cytokine production in acute leukemia involving progenitors of dendritic Langerhans' cells

To date no hematopoietic progenitors of dendritic Langerhans' cells (DLC), which represent an highly efficient class of antigen presenting cells, have been identified or the cytokines they elaborate have been defined. Here we describe an acute leukemia patient whose blasts (90-96% in peripheral blood and bone marrow) had a phenotype consistent with putative progenitors of DLC. The patient was treated with ara-C and VP-16 but did not achieve remission. The blasts had lobulated nuclei, no cytoplasmic vacuolation or Auer rods and were weakly positive for acid phosphatase and non-specific esterase and negative for PAS, granzyme A, dipeptidyl aminopeptidase IV, ATPase/ADPase and lysozyme production. The blasts were positive for CD1a, CD4, CD16, CD35, HLADR, HLADQ, CD11b, CD11c, CD14, CD33, CD34, CD11a, CD71, CD19, CD25, IL-2R beta and negative for CD2, CD7, CD8, CD10, CD22, CD56, CD57, surface or cytoplasmic CD3, TCR delta and TCR beta, HTLV-1p19 and P-glycoprotein. On liquid culture with or without 5 x 10(-9) M 12-O-tetradecanoylphorbol-13-acetate (TPA) for 3 days, the blasts formed aggregates of proliferating and elongating cells on the wall of the flasks with a decline in CD34, numerous dendritic processes appeared on the cells and there was strong positivity for ATPase/ADPase, but no other changes in phenotype. No macrophages were observed, indicating derivation from separate DLCs. Cytogenetic analysis showed chromosomal abnormalities and electron microscopy showed Birbeck granules. Southern blotting of DNA showed rearrangement of one allele for both JH and TCR beta but no HTLV-1 related sequences. Culture supernatants from blasts cultured with or without TPA showed the production of large amounts of IL-8, IL-6, TNF-alpha, MIP-1 alpha, IL-10 and interferon gamma and modest amounts of IL-1 alpha, GM-CSF and stem cell factor. The presence not only of CD1a, HLADR, HLADQ and many other characteristics including Birbeck granules, but also differentiation along the lines of DLC with appearance of dendritic processes on the cells and expression of ATPase/ADPase activity, indicate that the leukemic blasts in our patient represented a leukemic counterpart of normal progenitors of DLC and the leukemia a new entity which could possibly be classified as AML-M8. Lastly, many pro-inflammatory cytokines produced by DLC could contribute to inflammation and IL-10 to immunosuppression.

Soluble interleukin-2 receptor, soluble CD8 and soluble intercellular adhesion molecule-1 levels in hematologic malignancies

Plasma levels of soluble interleukin-2 receptor (sIL-2R), soluble CD8 (sCD8) and soluble intercellular adhesion molecule 1 (sICAM-1) were determined by ELISA assays in about 100 patients with hairy cell leukemia (HCL), acute myelomonocytic leukemia (AMMoL), acute myelocytic leukemia (AML), chronic lymphocytic leukemia (CLL), prolymphocytic leukemia (PLL), acute lymphoblastic leukemia (ALL), adult T-cell leukemia (ATL), and mycosis fungoides (MF). Additionally, cultured AML, ALL, and CLL cells grown with and without 12-0-tetra-decanoyl-phorbol-13-acetate (TPA) were tested for IL-2R (CD25) expression by indirect immunofluorescence. Supernatants of these cultures were also tested for sIL-2R by ELISA. Elevated sIL-2R levels were found in HCL patients at initial diagnosis and relapse, in AMMoL, in AML, in the accelerated and non-accelerated phases of B-CLL, in PLL, in non-T/non-B ALL, in B-ALL in mixed lineage ALL, in T-CLL, in T-ALL, and in active MF. Reduced levels of sIL-2R were encountered in HCL patients in remission, in pre-T-ALL, and in MF patients in remission. Also, in non-accelerated CLL sIL-2R levels were less elevated than in later stages of the disease. In T-CLL, sIL-2R was only slightly elevated. Thus, we believe sIL-2R could prove to be a useful marker of disease stage, subtype, and prognosis in several hematologic malignancies. The cultures with and without TPA suggested that the undetermined source of sIL-2R in HCL, ALL and AML could indeed be the malignant cells but perhaps not so in the case of B-CLL. Plasma sCD8 was found to be below normal control levels in HCL, and lowest in relapsing cases. In addition, sCD8 levels were below normal in pre-T-ALL, and in MF. Levels in the non-accelerated phase of B-CLL approximated those of controls. Elevated levels of sCD8 were observed in AML, AMMoL, accelerated stage B-CLL, PLL, non-T/non-B ALL, B-ALL, mixed lineage ALL, T-ALL, T-CLL, and ATL. Thus, in a few instances, sCD8 may also correlate with disease subtype, as well as stage. Although sICAM-1 levels were elevated in all leukemias, its levels in CLL did not appear to be related to disease activity. Whether this is true or not for other leukemias would require additional work on sICAM-1 levels and its relationship to disease activity and prognosis.

Constitutive production of interleukin-8 (IL-8) by normal and malignant human B-cells and other cell types

The culture supernatants from 43 human cell lines obtained during log phase and from purified normal peripheral blood B-lymphocytes cultured at 10(6) cells ml-1 for 48 h in RPMI 1640-5% fetal calf serum were examined for interleukin-8 (IL-8) using Elisa kits. Constitutive IL-8 production was found for 14/15 B-cell lines (5 derived from normal persons and 2 from AML patients, 1 pre-B-ALL, 2 CLL with trisomy 12, 2 HTLV-I+, 1 HTLV-II+, 1/2 Burkitt lymphoma), 4/16 T-cell lines (3/6 HTLV-I+, 1 HTLV-II+, 0/9 T-ALL), myeloid line HL-60, monocytoid line U937, 3/3 ovarian carcinoma, 1/1 endometriosis, 2/2 normal fibroblast, 0/2 C-ALL, 0/1 pre-erythroid line K562, as well as for normal B-lymphocytes. Later, cells examined by indirect immunofluorescence using IL-8 antibodies gave a positive reaction. DNA from 4 IL-8 producing and 3 non-producing cell lines, when probed with IL-8 cDNA gave the same 3.5 kb EcoRI fragment indicating similarities of the IL-8 gene in these cells. Two B-cell lines examined showed the expression of 1.8 kb IL-8 mRNA. These results indicate IL-8 production by a greater variety of cells than previously believed which open possibilities for new IL-8-mediated immune functions by such cells as B-cells.

Phenotypic and genotypic characterization of 14 leukemia and lymphoma cell lines with 11q23 translocations

11q23 translocation is the most popular chromosomal abnormality in infant leukemia. In adults, it is often encountered in non-Hodgkin's lymphoma (NHL). In this study, we analyzed the phenotypic and genotypic characteristics of 9 acute leukemic cell lines with 11q23 translocations and one with deletion of the 11q23 locus, nine of which were established by researchers in this group, together with 4 NHL cell lines with 11q23 translocations. All lines were considered to belong to the B-cell lineage at different stages. All 10 leukemic lines showed clonal rearrangement of the immunoglobulin heavy chain (IgH) gene: two corresponded to the B-precursor stage (CD19+, cytoplasmic mu-), while the other 8 corresponded to the pre-B stage (cytoplasmic mu+). All 4 NHL lines showed rearrangements of both the IgH and Ig kappa genes with three expressing surface Ig; specifically, mature B-cell phenotype. As for myelocytic-monocytic markers, at least one out of 4 antigens examined were positive in 8 of the 10 leukemic cell lines, while only one of the 4 NHL lines was reactive. There were essentially no clear phenotypic or genotypic differences between t(4;11) and t(11;19) cell lines, supporting the view that both diseases have similar clinicopathological characteristics. These cell lines are also valuable for cloning genes at the chromosomal breakpoints.

Cytogenetic abnormalities in childhood acute lymphoblastic leukemia correlates with clinical features and treatment outcome

Virtually all cases of childhood acute lymphoblastic leukemia have chromosomal abnormalities. Non-random chromosomal abnormalities have been correlated with leukemic cell lineage, the degree of cell differentiation and certain clinical and biologic features. Cytogenetic findings have prognostic significance, but the adverse influence of many rearrangements, including most chromosomal translocations, may be offset by the greater cytoreductive effects of intensified therapy. Cytogenetic abnormalities have also provided focus for molecular studies of leukemogenesis. Such studies have recently identified key genes and their protein products which play important roles in malignant transformation and proliferation.

Acute leukemias with the t(4;11)(q21;q23)

The t(4;11)(q21;q23) has been associated with marked lineage heterogeneity. Most of the reported cases were classified as acute lymphoblastic leukemia (ALL). The t(4;11) is one of the commonest specific chromosomal translocations in ALL, occurring in 2% of childhood and 5% of adult cases. In childhood ALL, this translocation is associated with female sex, age less than 1 year, hyperleukocytosis, CD10-/CD19+ B-precursor cell immunophenotype, and myeloid-associated antigen (CD15) expression. There also appears to be an age-related difference in treatment outcome. Adults had the worst prognosis, and children aged 1 to 9 years appeared to have a better outcome than infants or adolescents. Reported cases of acute myeloid leukemia (AML) or secondary leukemia with the t(4;11) have not been well characterized. It is intriguing that virtually all of the reported cases with secondary leukemia had received epipodophyllotoxins or doxorubicin, agents that affect topoisomerase II and are associated with secondary AML characterized by 11q23 abnormalities. Identification of the involved gene(s) in the t(4;11) will provide a molecular approach permitting more accurate classification of these cases.

Identification of a gene, MLL, that spans the breakpoint in 11q23 translocations associated with human leukemias

Recurring chromosomal translocations involving chromosome 11, band q23, have been observed in acute lymphoid leukemias and especially in acute myeloid leukemias. We recently showed that breakpoints in four 11q23 translocations, t(4;11)(q21;q23), t(6;11)(q27;q23), t(9;11)(p22;q23), and t(11;19)(q23;p13.3), were contained within a yeast artificial chromosome clone bearing the CD3D and CD3G gene loci. We have identified within the CD3 yeast artificial chromosome a transcription unit that spans the breakpoint junctions of the 4;11, 9;11, and 11;19 translocations, and we describe two other, related transcripts that are upregulated in the RS4;11 cell line. We have named this gene MLL (myeloid/lymphoid, or mixed-lineage, leukemia.

Cytogenetic evidence of involvement of an early progenitor myeloid cell in 4;11 translocation-associated acute leukemia

The t(4;11)(q21;q23)-associated acute leukemia may show both lymphoid and myelomonocytic features, which suggests a pluripotent progenitor stem cell as the hematopoietic cell involved in this neoplastic process. However, there is no cytogenetic evidence to support this contention. We present a case of acute myelomonocytic leukemia (M4, FAB subtype) with t(4;11)(q21;q23), which was also found in several hypertetraploid metaphases probably corresponding to megakaryocytes. This confirms the cellular origin in an early progenitor myeloid cell of this type of acute leukemia.

Investigation of the CD10 (cALLA) negative acute lymphoblastic leukaemia: further description of a group with a poor prognosis. French Groupe d'Etude Immunologique des Leucémies

The absence of CD10 (cALLA) in non-T non-B acute lymphoblastic leukaemia (ALL) is usually considered to be of adverse prognostic significance. From a large multicentre series of phenotyped ALL, we have identified a group of 23 non-T non-B ALL where blast cells were CD10 negative and CD19 positive. Class II antigens were present in 80% and C19 in 70%. Eight patients had successful karyotype analysis at diagnosis, and an additional patient at first relapse. Seven of these karyotypes showed a (4;11) (q21;q23) translocation. Most of the patients (70%) were young females, and they often presented with organomegaly. Six patients were less than 1 year old. The white cell count was over 100 x 10(9)/l in 48% of the cases. The FAB type was L2 in 56% of the patients. The most striking features were the poor response to therapy and survival. Six patients never attained complete remission and nine patients relapsed, most of them during the first year after diagnosis. Allogeneic bone marrow transplantation was performed in three children, of whom two are still alive 2 years after diagnosis. This study emphasizes the prognostic value of immuno-phenotypic and karyotypic investigations of ALL.

Acute leukemia with coexpression of lymphoid and myeloid phenotypes

A multiparameter analysis of 706 cases of acute leukemia (AL) over a two-year period revealed only six cases (0.86 per cent) with coexpression of lymphoid and myeloid phenotypes. In three cases, expression of both lymphoid and myeloid markers by the majority of the blast cells suggested a 'biphenotypic' pattern while in the remaining three cases, the lymphoid and myeloid phenotypes were segregated into two morphologically distinct populations of blast cells indicating a 'biclonal' distribution. The poor response to anti-acute lymphoblastic leukemia therapy in five of these six cases underlines the bad prognostic significance of coexpression of lymphoid and myeloid phenotypes in AL. The incidence of 'mixed lineage' phenotype in the present series appears very low.