A patient with chronic eosinophilic leukemia and a unique complex chromosomal translocation 46,XY,t(3;9;5)(q25;q34;q33) who had elevated blood interleukin-5 is reported. Complete cytogenetic remission was induced by interferon-alpha after treatment failure with corticosteroids and cytotoxic drugs. Severe cardiopulmonary symptoms due to hypereosinophilia and thromboembolic complication improved dramatically in the first 6 months of interferon therapy. Since it is known that the gene encoding for interleukin-5 resides on the long arm of chromosome 5, it may be possible that the chromosomal translocation in our patient resulted in overproduction of this cytokine, and our findings may be helpful for understanding the pathogenesis of this disorder.

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L265P mutation in the MYD88 gene has recently been reported in Waldenström’s macroglobulinemia; however the incidence has been different according to the methods used. To determine the relevance and compare the incidence by different methods, we analyzed the L265P mutation in bone marrow mononuclear cells from lymphoid neoplasms. We first performed cloning and sequencing in 10 patients: 8 Waldenström’s macroglobulinemia; 1 non-IgM-secreting lymphoplasmacytic lymphoma; and 1 low grade B-cell lymphoma with monoclonal IgG protein. The L265P mutation was detected in only 1/8 Waldenström’s macroglobulinemia patients (2 of 9 clones). To confirm these results, direct sequencing was performed in the 10 patients and an additional 17 Waldenström’s macroglobulinemia patients and 1 lymphoplasmacytic lymphoma patient. Nine of 28 patients (7/25 Waldenström’s macroglobulinemia, 1/2 lymphoplasmacytic lymphoma, and B-cell lymphoma) harbored the mutation. We next tested for the mutation with BSiE1 digestion and allele-specific polymerase chain reaction in the 28 patients and 38 patients with myeloma. Aberrant bands corresponding to the mutation were detected by BSiE1 digestion in 19/25 patients with Waldenström’s macroglobulinemia (76%), 1/2 lymphoplasmacytic lymphoma and B-cell lymphoma, but not in the 38 myeloma patients. The L265P mutation was more frequent in patients with Waldenström’s macroglobulinemia than in those with myeloma (p=1.3x10-10). The mutation was detected by allele-specific polymerase chain reaction in 18/25 Waldenström’s macroglobulinemia patients (72%). In the 25 Waldenström’s macroglobulinemia patients, the L265P was more frequently detected by BSiE1 digestion than by direct sequencing (p=5.3x10-4), and in males (15/16, 94%) than in females (4/9, 44%) (p=1.2x10-2). No siginificant difference was observed in the incidence of the L265P mutation between BSiE1 digestion and allele-specific polymerase chain reaction (p=0.32). These results suggest that the L265P mutation is involved in the majority of Waldenström’s macroglobulinemia. BSiE1 digestion and allele-specific polymerase chain reaction may detect a small fraction of mutated cells in some cases.

Studies were undertaken to determine whether leukemia and lymphoma cells would be lysed by autologous and allogeneic lymphokine-activated killer (LAK) cells. Peripheral blood mononuclear cells (PBMC) from patients and normal donors were cultured for five days, 2 weeks, and 4 weeks with medium containing 2,500 units of recombinant interleukin 2 (IL-2) per mL, and their cytotoxicity was assayed by a five-hour 51Cr- release test. Of primary tumors isolated from patients with acute nonlymphoblastic leukemia, acute lymphoblastic leukemia, and non- Hodgkin's lymphoma, tumors of 37 out of 40 patients tested were shown to be susceptible to normal donors' LAK, and tumors of 18 of 20 patients tested were shown to be susceptible to autologous LAK. LAK cultured for longer periods showed a tendency to have lower cytotoxicity. LAK had also low, but significant, levels of cytotoxicity for nonmalignant target cells. Because PBMC expanded in IL-2-containing medium consisted mainly of OKT3-positive pan T cells, OKT8-positive suppressor/cytotoxic cells, and Leu-11-positive natural killer (NK) cells, and treatment with OKT3 and Leu-11 monoclonal antibodies (mAb) reduced LAK activity for autologous and allogeneic tumor cells, both T and NK cells appeared to be effector cells for LAK activity. Mechanisms of target-cell recognition in the LAK system seem to be different from those in alloreactive cytotoxic T lymphocytes (CTL) based on the results that, while cytotoxicity of alloreactive CTL was inhibited by the treatment of effector cells with mAb, OKT3, and OKT8, and by the treatment of target cells with a mAb that reacts with HLA class I antigen, LAK activity was not inhibited by the above treatment. When chromosomes of IL-2-expanded PBMC in nine patients and two normal individuals were analyzed, PBMC from one patient showed chromosomes of clonal abnormalities, and PBMC from five donors showed those of nonclonal abnormalities.

Nucleophosmin (NPM1) gene exon 12 mutations are frequently present in patients with acute myeloid leukemia (AML) with normal karyotype. The NPM1 gene is located on chromosome 5q35, which is often affected in myeloid malignancies including myelodysplastic syndrome (MDS). This suggests that the NPM1 gene is a one of the target genes affected by chromosome 5 abnormalities and play a role in the development of MDS. It has not been clarified whether MPM1 mutations are present in patients with MDS and AML with chromosome 5 abnormalities. Therefore, we carried out a mutational analysis on the NPM1 gene exon 12. NPM1 mutations were not detected in the 28 patients with MDS and AML with chromosome 5 abnormalities.

Two cases of myeloproliferative disorders terminating in acute megakaryoblastic leukemia are reported. One case began as primary myelofibrosis and the other as chronic myelogenous leukemia. Blast cells in the acute leukemic phase were identified as megakaryoblasts by the presence of platelet peroxidase. The clinical course is described, and the morphology, immunologic studies, and ultrastructure studies of the blast cells are reported. On cytogenetic analysis both cases had a translocation involving the No. 3 chromosome locus q26.2. The present data suggest that 3q26 may be associated with transformation of the megakaryocytic lineage.

Five patients with refractory anemia were treated with high-dose methylprednisolone. An immediate and long-lasting hematological improvement without serious side effects was achieved in two of the patients, although chromosomal abnormalities persisted in both. The clinical course and laboratory data of these two patients are described. Restoration of normal hematopoiesis was achieved regardless of the enhancement of colony formation of granulocyte progenitor cells by the simultaneous addition of hydrocortisone in vitro. The same treatment was given to six patients who had refractory anemia with an excess of myeloblasts (RAEB), but no improvement was observed in any of these patients. It appears that high-dose methylprednisolone can be valuable in the treatment of refractory anemia, but is not useful for RAEB.

Mutations of the p53 tumour suppressor gene have frequently been observed in several types of solid tumours and are believed to be implicated in the development of these tumours. To determine the relevance of p53 mutations in haematologic neoplasms, we performed polymerase chain reaction-single strand conformation polymorphism analysis on the p53 gene in 45 patients with various types of haematologic neoplasms. In exons 5-8 containing highly conserved regions, mobility shifts indicating sequence alterations were detected in four of the 45 patients, and subsequent sequencing was performed. A point mutation resulting in a novel stop codon was detected at codon 213 in one of 23 cases of chronic myelogenous leukaemia (one of five cases of blast crisis). Point mutations causing amino acid substitutions were detected in one of four cases of myelodysplastic syndrome at codon 195, one of three cases of adult T-cell leukaemia at codon 281, and one of eight cases of acute lymphoblastic leukaemia at codon 281, and these missense mutations were accompanied by loss of the wild type allele. Patients harbouring these nonsense and missense mutations were in advanced disease stages. These findings suggest that mutational inactivation of the p53 gene is infrequent but is involved in the tumorigenesis of several types of haematologic neoplasms at least in some cases.