Maho Ishikawa

A Novel Gene, ANKRD28 on 3p25, Is Fused with NUP98 on 11p15 in a Cryptic 3-Way Translocation of t(3;5;11)(p25;q35;p15) in an Adult Patient with Myelodysplastic Syndrome/Acute Myelogenous Leukemia

We identified a novel gene fusion of ANKRD28 (ankyrin repeat domain 28) on 3p25 to NUP98 on 11p15 in a patient with adult myelodysplastic syndrome/acute myelogenous leukemia. A partially cryptic 3-way translocation, t(3;5;11)(p25;q35;p15), that had initially been supposed to be t(3;5)(p25;q35) was revealed by precise breakpoint mapping via fluorescence in situ hybridization analysis with bacterial artificial chromosome clones. This translocation produces the expression of 2 in-frame fusion transcripts, the novel ANKRD28-NUP98 and NUP98-NSD1, and 1 out-of-frame NSD1-ANKRD28 transcript. Transient overexpression of ANKRD28-NUP98 in NIH/3T3 cells, but not the C-terminal deletion mutant of ANKRD28 (?C-ANKRD28), caused significantly increased focus formation compared with mock-transfectant controls. ANKRD28-NUP98 was localized in the nucleolus and cytoplasm, whereas ANKRD28 and ?C-ANKRD28 were found exclusively in the cytoplasm. Alteration of the subcellular localization of ANKRD28 might have contributed to the leukemogenesis in this case. This report is the first of ANKRD28 as an NUP98 fusion partner, and this case implies that this fusion may be responsible for hematologic malignancies.

Long-term improvement of anaemia in a patient with aplastic anaemia by short-term administration of pegylated recombinant human megakaryocyte growth and development factor.

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Incidences and outcomes of therapy-related chronic myeloid leukemia in the era of tyrosine kinase inhibitors: surveillance of the CML Cooperative Study Group

This study was performed to investigate the features and outcome of patients with therapy-related chronic myeloid leukemia (TR-CML) who were treated with tyrosine kinase inhibitors (TKIs). The analysis included 308 patients with CML in the chronic phase who were extracted from the CML Cooperative Study Group database. Of these patients, 11 (3.6%) were identified as having TR-CML. No differences in age, sex, white blood cell count, hemoglobin level, platelet count, or European Treatment and Outcome Study risk were observed between patients with TR-CML vs. de novo CML. However, the responses of TR-CML patients to TKIs (6, 3, and 2 received imatinib, nilotinib, and dasatinib, respectively) were excellent; all achieved major or deep molecular response. Furthermore, the outcomes of TR-CML patients were relatively favorable; the 3-year event-free survival rates in the TR-CML and de novo CML patients were 100% and 94%, respectively; the difference was not statistically significant. In conclusion, our study showed that TR-CML patients could achieve a good clinical course with TKI therapy. Detailed investigations of TR-CML may provide new insights into CML biology.

Introduction of second-generation tyrosine kinase inhibitors may reduce the prognostic impact of high-risk patients, according to the European treatment and outcome study (EUTOS) score

Abstract Our study aims to highlight the critical role of the introduction of second generation tyrosine kinase inhibitors (2nd TKIs) on the prognosis of patients with chronic myeloid leukemia (CML) in chronic phase (CML-CP), as determined by European Treatment and Outcome Study (EUTOS) system. Patients who were diagnosed with CML-CP before March 2009 were classified into the imatinib group, and those diagnosed after April 2009 were classified into the 2nd TKI group. EUTOS high-risk patients exhibited significantly worse outcomes in terms of event-free survival (EFS), progression-free survival (PFS), and CML-associated death than those considered to be low-risk. Risk stratification by EUTOS score was predictive of risk-associated clinical outcomes in patients classified into the imatinib group; however, the EUTOS score failed to predict the outcomes of patients classified into the 2nd TKI group. Our data suggest that the introduction of 2nd TKIs might have improved treatment outcomes, particularly in EUTOS high-risk patients.

Comparative quantitative analysis of BCR-ABL transcripts with the T315I mutant clone by polymerase chain reaction (PCR)–Invader method

Drug resistance is a serious complication in the treatment of chronic myeloid leukemia (CML). The most common and best-characterized mechanism of secondary imatinib resistance in CML is the development of kinase domain mutations in the BCR-ABL gene. Second-generation tyrosine kinase inhibitors, such as dasatinib or nilotinib, overcome most of these mutations, but they are not effective against the T315I mutant. To determine whether these mutations contribute to clinical resistance, it is necessary to monitor the ratio of the mutant and wild-type forms. Here, we developed a polymerase chain reaction (PCR)-Invader assay for comparative quantitative analysis (qPI assay) of BCR-ABL transcripts with the T315I mutant clone. T315I ratios were calculated for the wild-type and mutant fold-over-zero (FOZ) values. In examination with 2 kinds of plasmids containing wild-type or T315I mutant PCR amplicons, mutant FOZ values were detected down to 1% of the total. The results of 12 serial samples from 2 patients (case A: Philadelphia-positive acute lymphoblastic leukemia and case B: CML) with the T315I mutant clone were compared with those of direct sequencing or 2 kinds of allele-specific oligonucleotide (ASO)-PCR. All samples showed the T315I mutation by qPI assay and ASO-PCR, and 10 samples showed it by direct sequencing. Significant correlation (correlation coefficient; r2 = 0.951) was noted between the qPI assay and quantitative ASO-PCR to analyze T315I mutant ratios. Thus, the qPI assay is a useful method for evaluating the T315I mutant clone in BCR-ABL transcripts.

The progression of severe aplastic anemia to hypoplastic leukemia in a long-term observation after the administration of pegylated rHuMGDF

Thrombopoietin (TPO) is a critical regulator of hematopoiesis. We previously reported that a severe aplastic anemia (SAA) who received a short-term administration of pegylated recombinant human megakaryocyte growth and development factor (rHuMGDF). A trilineage hematologic response was induced, however the patient was diagnosed with leukemia after nine years and eight months from administration of rHuMGDF. In recent reports, somatic mutations in myeloid cancer candidate genes were present in one-third of the AA. A mutant clone may be expanded by rHuMGDF in our patient. The long-term safety of patients treated with TPO and eltrombopag remains unknown. Careful observations are warranted hereafter.

Features of vascular adverse events in Japanese patients with chronic myeloid leukemia treated with tyrosine kinase inhibitors: a retrospective study of the CML Cooperative Study Group database

This study investigated the incidence rate and features of vascular adverse events (VAEs) in Japanese patients with chronic myeloid leukemia (CML) who were treated with tyrosine kinase inhibitors (TKIs). The analysis included 369 CML patients in the chronic or accelerated phases, selected from the CML Cooperative Study Group database; 25 events in 23 (6.2%) of these patients were VAEs. At the time of VAE incidence, nine patients were on treatment with imatinib, 12 with nilotinib, three with dasatinib, and one with bosutinib. VAE incidence comprised 13 cases of ischemic heart disease (IHD), eight of cerebral infarction (CI), and four of peripheral arterial occlusive disease (PAOD). IHD incidence rate in the study population was higher than that in the age-matched general population, particularly in nilotinib-treated patients, while CI incidence rate was almost equivalent. Compared with the Suita score, the SCORE chart and the Framingham score risk assessment tools detected more patients with high or very high risk of VAEs. In conclusion, incidence of IHD requires closer monitoring in nilotinib-treated patients. More detailed investigations for determining the most useful tool to predict VAE incidence and long-term analysis of therapy-related VAE cases are needed for improving safety during TKI therapy.

Correlation Between Dysplastic Lineage and Type of Cytopenia in Myelodysplastic Syndromes Patients With Refractory Anemia According to the FAB Classification

OBJECTIVES To analyze the correlation between dysplastic lineage and type of cytopenia in myelodysplastic syndromes. METHODS We analyzed the correlation between dysplasia and cell count using the data set of our previous morphologic study. RESULTS There were no correlations between dysgranulopoiesis of 10% or more and absolute neutrophil count (ANC). Similarly, hyposegmented mature neutrophils (Pelger) of 10% or more were not related to ANC. Interestingly, the platelet count of patients with dysmegakaryopoiesis (dys Mgk) was higher than that of patients without dys Mgk (dys Mgk ≥10% vs <10%, P = .08; dys Mgk ≥40% vs <40%, P = .02; micromegakaryocytes ≥10% vs <10%, P = .004). CONCLUSIONS Since low cell counts did not correlate with the presence of dysplastic features, we suggest that dysplastic features do not directly relate to apoptosis.