Masatsugu Tanaka

Cell-cycle-dependent regulation of human aurora A transcription is mediated by periodic repression of E4TF1.

Human aurora A is a serine-threonine kinase that controls various mitotic events. The transcription of aurora A mRNA varies throughout the cell cycle and peaks during G2/M. To clarify the transcriptional mechanism, we first cloned the 1.8-kb 5′-flanking region of aurora A including the first exon. Transient expression of aurora Apromoter-luciferase constructs containing a series of 5′-truncated sequences or site-directed mutations identified a 7-bp sequence (CTTCCGG) from −85 to −79 as a positive regulatory element. Electromobility shift assays identified the binding of positive regulatory proteins to the CTTCCGG element. Anti-E4TF1–60 antibody generated a supershifted complex. Furthermore, coexpression of E4TF1–60 and E4TF1–53 markedly increased aurora Apromoter activity. Synchronized cells transfected with the aurora A promoter-luciferase constructs revealed that the promoter activity of aurora A increased in the S phase and peaked at G2/M. In addition, we identified a tandem repressor element, CDE/CHR, just downstream of the CTTCCGG element, and mutation within this element led to a loss of cell cycle regulation. We conclude that the transcription of aurora A is positively regulated by E4TF1, a ubiquitously expressed ETS family protein, and that the CDE/CHR element was essential for the G2/M-specific transcription of aurora A.

Long-Term Outcome of Human Herpesvirus-6 Encephalitis after Allogeneic Stem Cell Transplantation

Human herpesvirus-6 (HHV-6) encephalitis is recognized as a relatively rare, but sometimes lethal, complication of allogeneic hematopoietic stem cell transplantation (HSCT). Although the development of new diagnostic techniques and antiviral therapy has improved, the prognosis of encephalitis is still unclear. We surveyed 197 patients who underwent allogeneic HSCT between January 2004 and March 2008 at our institution, and 8 (4.0%) were diagnosed as having HHV-6 encephalitis. Five were male and 3 were female, with a median age of 40.5 years. The median onset of HHV-6 encephalitis was 18 days after HSCT, and the median duration of antiviral therapy was 41 days. The median survival time from the onset of encephalitis was 23.1 months (range: 2.7-66.7), and 3 patients died of unrelated causes (sepsis in 2 and gastrointestinal tract bleeding in 1). Cord blood transplantation was identified as the only independent risk factor (relative risk [RR] = 4.98; P = .049) by multivariate analysis. There was no statistical significance of survival after HSCT between the patients with HHV-6 encephalitis and those without HHV-6 encephalitis (the 2-year survival rate was 60% and 52.6%, respectively; P = .617). Four of the 5 surviving patients were unable to return to society because of neuropsychological disorders, including anterograde amnesia and seizures with prominent hippocampal atrophy. Although HHV-6 encephalitis occurring after HSCT is now becoming a curable complication, its sequelae, such as neuropsychological disorders, have a marked influence on the quality of life of long-term survivors. Accordingly, it is necessary to identify risk factors for HHV-6 encephalitis and establish methods for prevention of this complication.

Human herpesvirus 6 meningoencephalitis in allogeneic hematopoietic stem cell transplant recipients

We retrospectively investigated the clinical characteristics of human herpesvirus 6 (HHV-6) meningoencephalitis within 100 days after allogeneic hematopoietic stem cell transplantation (HSCT). Of 1148 patients who received transplants between January 1999 and December 2003, 11 patients (0.96%) with HHV-6 meningoencephalitis were identified. Ten of 11 recipients received hematopoietic stem cells from donors other than HLA-identical siblings. Confusion was the most frequent central nervous system (CNS) symptom, and a skin rash with high-grade fever preceded the CNS symptoms in 9 patients. Magnetic resonance imaging of the brain showed an abnormal increased T2 signal in the hypothalamus of 5 patients. Eight patients were treated with ganciclovir, and an improvement of CNS symptoms was obtained in 3 patients; 3 patients treated with acyclovir showed no improvement. Improvement in the meningoencephalitis seemed less frequent in patients with abnormal findings in the hypothalamus than in those without such findings. Because the symptoms of HHV-6 meningoencephalitis mimicked those of cyclosporine- or tacrolimus-induced encephalopathy, the drugs were withdrawn at the onset of CNS symptoms in 10 patients, resulting in the development of grade IV graft-versus-host disease (GVHD) in 5 patients.Three patients died of HHV-6 menin-goencephalitis, and 6 died of other causes, including GVHD. In conclusion, HHV-6 meningoencephalitis is a rare but potentially life-threatening complication in patients who undergo allogeneic HSCT. Careful assessment of the clinical findings and the brain may allow early and precise diagnosis of HHV-6 meningoencephalitis and contribute to improving its prognosis.

Pretransplant serum ferritin is associated with bloodstream infections within 100 days of allogeneic stem cell transplantation for myeloid malignancies

We retrospectively studied the association between iron overload and bloodstream infections (BSI) in the 100-day period following allogeneic hematopoietic stem cell transplantation (allo-HSCT) for acute myeloid leukemia or myelodysplastic syndromes. Serum ferritin was measured before transplantation to evaluate iron overload. Of 114 adult patients who underwent transplantation between 2000 and 2008, 36 (32%) developed BSI. Of the 44 isolates, 63% were Gram-positive bacteria, 32% were Gram-negative bacteria, and 4% were fungi. The median time to the onset of the first BSI was day 28 (range day 0–95) after transplantation. Univariate analysis revealed a significantly higher incidence of BSI in the high (≥1,000 ng/ml, n = 57) than in the low (<1,000 ng/ml, n = 57) ferritin group (42.1 versus 21.1%, respectively, P = 0.017). Peripheral blood stem cell transplantation (PBSCT) (n = 23) showed a greater protective effect against BSI compared with bone marrow (n = 71) and cord blood (n = 20) transplantation. Pretransplantation serum ferritin (HR = 2.844, 95% CI: 1.180–6.859, P = 0.020) and PBSCT (HR = 0.135, 95% CI: 0.025–0.717, P = 0.019) were significant factors on multivariate analysis. In conclusion, pretransplantation serum ferritin significantly predicts BSI within the 100-day period after allo-HSCT.

Impact of age on outcomes of allogeneic hematopoietic stem cell transplantation with reduced intensity conditioning in elderly patients with acute myeloid leukemia.

Previous studies have repeatedly reported that increasing age is a significant risk factor for worse outcomes after allogeneic hematopoietic stem cell transplantation (allo‐HSCT) among patients with acute myeloid leukemia (AML). However, more recent studies reported conflicting results regarding the association between age and outcomes in elderly patients. Therefore, we conducted a large‐scale, nationwide retrospective study to examine the impact of age on outcomes of allo‐HSCT with reduced intensity conditioning (RIC) for AML patients who were older than 50 years. Of the 757 patients, 89 patients (11.8%) were 50–54, 249 patients (32.9%) were 55–59, 301 patients (39.8%) were 60–64 and 118 patients (15.6%) were ≥65 years old. The 3‐year overall survival (OS) (47.8, 45.2, 37.9, and 36.6% for patients aged 50–54, 55–59, 60–64, and ≥65 years, respectively, P = 0.24) and nonrelapse mortality (NRM) (24.0, 22.8, 29.2, and 27.6% for patients aged 50–54, 55–59, 60–64, and ≥65 years, respectively, P = 0.49) were not significantly different among the four age groups. Multivariate analysis revealed that increased age had no significant effect on OS or NRM after adjusting for covariates. These results suggested that advanced patient age is not a contraindication for RIC allo‐HSCT in elderly AML patients. Am. J. Hematol. 91:302–307, 2016.

European Treatment and Outcome Study score does not predict imatinib treatment response and outcome in chronic myeloid leukemia patients

The Sokal and Hasford scores were developed in the chemotherapy and interferon era and are widely used as prognostic indicators in patients with chronic myeloid leukemia (CML). Recently, a new European Treatment and Outcome Study (EUTOS) scoring system was developed. We performed a multicenter retrospective study to validate the effectiveness of each of the three scoring systems. The study cohort included 145 patients diagnosed with CML in chronic phase who were treated with imatinib. In the EUTOS low‐ and high‐risk groups, the cumulative incidence of complete cytogenetic response (CCyR) at 18 months was 86.9% and 87.5% (P = 0.797) and the 5‐year overall survival rate was 92.6% and 93.3% (P = 0.871), respectively. The cumulative incidence of CCyR at 12 months, 5‐year event‐free survival and 5‐year progression‐free survival were not predicted using the EUTOS scoring system. However, there were significant differences in both the Sokal score and Hasford score risk groups. In our retrospective validation study, the EUTOS score did not predict the prognosis of patients with CML in chronic phase treated with imatinib.

Four-Color Flow Cytometric Analysis of Myeloma Plasma Cells

We monitored the behavior of residual myeloma plasma cells in patients with multiple myeloma after high-dose therapy and autologous or allogeneic transplantation using 3 methods of a flow cytometric technique using 4-color staining, immunofixation, and polymerase chain reaction approaches. We analyzed 17 cases by a relatively simple flow cytometric technique using CD38/CD45/CD19/CD56. Detectable myeloma plasma cells were found in 5 patients at diagnosis and 9 patients after treatment. Of 14 cases, 9 (64%) had CD19-CD56+ myeloma plasma cells, and 5 (36%) of 14 had CD19-CD56- myeloma plasma cells. When 37 bone marrow samples that had less than 5% myeloma plasma cells were assessed, myeloma plasma cells were detected in all 20 immunofixation-positive cases and 3 of 17 immunofixation-negative cases (P = .002). All 4 polymerase chain reaction-negative samples characterized as immunofixation-negative contained no detectable myeloma plasma cells. Flow cytometry can provide effective information to detect low levels of myeloma plasma cells.

Pretransplant serum ferritin has a prognostic influence on allogeneic transplant regardless of disease risk.

Abstract A multicenter retrospective analysis of the influence of pretransplant serum ferritin (SF) was performed in 261 adult recipients of allogeneic hematopoietic stem cell transplant (allo-HSCT), including 159 patients with acute myeloid leukemia (AML), 66 with acute lymphoid leukemia (ALL) and 36 with myelodysplastic syndrome (MDS). Patients were divided into subgroups according to the pretransplant SF level [< 1000 ng/mL (low) vs. ≥ 1000 ng/mL (high)] and disease status at transplant. A high SF level was significantly associated with high disease risk (p = 0.041), but pretransplant SF and disease risk were independent significant prognostic factors for overall survival (OS), disease-free survival (DFS) and non-relapse mortality rate (NRM) on multivariate analysis. The high-SF group showed a worse outcome than the low-SF group among both standard-risk patients (OS: 54% vs. 64%, p = 0.043; DFS: 46% vs. 57%, p = 0.031) and high-risk patients (OS: 16% vs. 35%, p = 0.001; DFS: 15% vs. 34%, p = 0.001). In conclusion, a high SF at transplant adversely influences the outcome of allo-HSCT regardless of disease risk in patients with acute leukemia and MDS.

The impact of the dose of natural killer cells in the graft on severe acute graft-versus-host disease after unrelated bone marrow transplantation

The impact of lymphocyte subpopulations on the outcome of bone marrow transplantation (BMT) remains uncertain. We investigated the relationship between the lymphocyte subpopulations of bone marrow grafts and the outcome of BMT. A total of 121 patients who underwent BMT at Kanagawa Cancer Center between 2000 and 2009 were analyzed. Grade III-IV acute graft-versus-host disease (GVHD) occurred in 35.9% of patients who received unrelated BMT with a CD56 cell dose ≤2.80×10(6)/kg versus only 9.7% of patients with a CD56 cell dose >2.80×10(6)/kg (P=0.017). In patients receiving related BMT, the cumulative incidence of grade III-IV acute GVHD did not differ significantly in relation to the CD56 cell dose. On multivariate analysis, older donor age (hazard ratio (HR): 1.09, 95% confidence interval (CI): 1.03-1.15, P=0.004) and a high dose of CD56 cells (>2.80×10(6)/kg) (HR: 0.15, 95%CI: 0.03-0.92, P=0.040) were significant determinants of grade III-IV acute GVHD after unrelated BMT. None of the lymphocyte subpopulations had a significant impact on the outcome of transplantation, including the rate of neutrophil engraftment, relapse, relapse-free mortality, and overall survival. Our findings suggest that a high natural killer cell dose prevents severe acute GVHD after unrelated BMT, while sparing the graft-versus-leukemia effect.

Low-dose cytarabine-induced hepatic and renal dysfunction in a patient with myelodysplastic syndrome.

We report a 49-year-old female patient with secondary myelodysplastic syndrome who developed liver dysfunction and acute renal failure caused by low-dose cytosine arabinoside (Ara-C) therapy. Treatment of low-dose Ara-C has widely been used for acute myelogeous leukemia and myelodysplastic syndrome, and it is thought to be a low toxicity except for myelosuppression. The patient complained of a transient adverse reaction in the second and third course of therapy. This rare case indicates that careful observation should be carried out during low-dose Ara-C therapy in view of allergic reactions.