A new method for maturity-dependent fractionation of neutrophil progenitors applicable for the study of myelodysplastic syndromes

We applied our new method, maturity-dependent fractionation of bone marrow-derived neutrophil progenitors, to a study of gene expression profiles during granulopoiesis in myelodysplastic syndromes. CD34(+) cells with low density [F1], CD11b(-)/CD16(-) [F2], CD11b(+)/CD16(-) [F3] and CD11b(+)/CD16(low) [F4] with intermediate density, CD11b(+)/CD16(int) [F5] and CD11b(+)/CD16(high) [F6] with high density were isolated from six patients. Although AML1 and C/EBP-ϵ mRNA peaked at F1 and F4, respectively, in healthy individuals, C/EBP-ϵ was maximized at F2/F3 in all patients, two of whom showed simultaneous peaks of AML1 at F2. Thus, this fractionation is useful to detect mistimed induction of granulopoiesis-regulating genes in myelodysplastic syndromes

Phase II Study of Dasatinib safety and efficancy for CP-CML at Tohoku

第73回日本血液学会学術集

Impairment of FOS mRNA stabilization following translation arrest in granulocytes from myelodysplastic syndrome patients.

Although quantitative and qualitative granulocyte defects have been described in myelodysplastic syndromes (MDS), the underlying molecular basis of granulocyte dysfunction in MDS is largely unknown. We recently found that FOS mRNA elevation under translation-inhibiting stimuli was significantly smaller in granulocytes from MDS patients than in healthy individuals. The aim of this study is to clarify the cause of the impaired FOS induction in MDS. We first examined the mechanisms of FOS mRNA elevation using granulocytes from healthy donors cultured with the translation inhibitor emetine. Emetine increased both transcription and mRNA stability of FOS. p38 MAPK inhibition abolished the emetine-induced increase of FOS transcription but did not affect FOS mRNA stabilization. The binding of an AU-rich element (ARE)-binding protein HuR to FOS mRNA containing an ARE in 3'UTR was increased by emetine, and the knockdown of HuR reduced the FOS mRNA stabilizing effect of emetine. We next compared the emetine-induced transcription and mRNA stabilization of FOS between MDS patients and healthy controls. Increased rates of FOS transcription by emetine were similar in MDS and controls. In the absence of emetine, FOS mRNA decayed to nearly 17% of initial levels in 45 min in both groups. In the presence of emetine, however, 76.7±19.8% of FOS mRNA remained after 45 min in healthy controls, versus 37.9±25.5% in MDS (P<0.01). To our knowledge, this is the first report demonstrating attenuation of stress-induced FOS mRNA stabilization in MDS granulocytes

T-cell prolymphocytic leukemia in Japan: is it a variant?

T-cell prolymphocytic leukemia (T-PLL) is characterized by a post-thymic immunophenotype, salient chromosome abnormalities, and an aggressive clinical course. However, cases in which these features are absent have been occasionally reported in Japan. Here, clinical and biological features of 13 T-PLL cases, diagnosed between 1992 and 2009 in the Tohoku region of Japan, were compared with three Western series. Median age was 64 (range 40-78) years old, and the male to female ratio (12:1) was higher than that of the Western series (P < 0.04). Presented manifestations were similar to those of Western cases, but central nervous system involvement, which is rare in Western cases, was observed in 3 of 13 cases (23 %) (P < 0.04). Immunophenotypic patterns were similar to those of Western cases, but HLA-DR was positive in 6 of 9 cases (67 %), which is distinct from Western cases (0-9 %) (P < 0.002). By chromosome analyses, 14q11 abnormality and trisomy 8q, which are common among Western cases (70-80 %), were not observed in any cases (P < 0.002). Morphologically, seven were classified as typical type, five as a small-cell variant, and one as a cerebriform variant. Seven cases experienced an aggressive course, whereas six experienced an indolent course over a median follow-up of 50 months. In contrast to Western cases, clinical courses were closely correlated with morphological types; 86 % of typical types were aggressive, whereas 83 % of small-cell types were indolent (P = 0.025). On the basis of these observations, together with previous Japanese cases in the literature, we propose that Japanese cases of T-PLL may constitute a variant

Reduction of c-Fos via Overexpression of miR-34a Results in Enhancement of TNF- Production by LPS in Neutrophils from Myelodysplastic Syndrome Patients.

Although increased TNF-α has been considered to cause ineffective hematopoiesis in myelodysplastic syndromes (MDS), the mechanisms of TNF-α elevation are not known. We recently found that c-Fos mRNA stabilization under translation-inhibiting stimuli was impaired in MDS-derived neutrophilic granulocytes. In the current study, we identified overexpression of c-Fos-targeting miR-34a and miR-155 as the cause of impairment. Expression levels of miR-34a but not miR-155 inversely correlated with ratios of c-Fos-positive cells in MDS-derived CD16+ neutrophils (r = -0.618, P<0.05), which were analyzed by flow cytometry. Among the seventeen patients, c-Fos was detectable in less than 60% of CD16+ cells in eight patients (Group A), while five (Group B) expressed c-Fos in more than 80% of CD16+ cells, which was consistent with the controls (88.6 ± 7.8%). Group A-derived granulocytes secreted more TNF-α in response to 1 μM LPS for 3 hours (735.4 ± 237.5 pg/mL) than Group B (143.5 ± 65.7 pg/mL, P<0.05) and healthy controls (150.8 ± 91.5 pg/mL, P<0.05). Knockdown of c-Fos in neutrophil-like differentiated HL60 increased the binding of NF-κB p65 to the promoter region of TNF-α DNA. Thus, c-Fos reduction via overexpression of miR-34a contributes to TNF-α overproduction under inflammatory stimuli in MDS

Safety and feasibility of high-dose ranimustine(MCNU), carboplatin, etoposide, and cyclophosphamide(MCVC) therapy followed by autologous stem cell transplantation for malignant lymphoma.

High-dose chemotherapy followed by autologous stem cell transplantation (auto-SCT) is widely used as a salvage therapy in the treatment of refractory malignant lymphoma. To investigate the safety and feasibility of a high-dose MCNU, carboplatin, etoposide and cyclophosphamide (MCVC) regimen, we conducted a prospective multicenter trial. Thirty patients with relapsed/refractory/poor-risk non-Hodgkin lymphoma (NHL n = 27) or Hodgkin lymphoma (HD n = 3) were uniformly treated with an MCVC regimen and underwent auto-SCT. The median follow-up duration of the surviving patients was 67 months (56-133 months). The major toxicities were anorexia (94 %), diarrhea (80 %), nausea (79 %), febrile neutropenia (70 %), alopecia (67 %) and mucositis (60 %). Three patients developed severe left ventricular dysfunction, and two patients developed severe sinusoidal obstructive syndrome (SOS). Of these patients, two died without disease progression. Treatment-related mortality was 6.6 %. Late-onset adverse events including two cases of cytomegalovirus pneumonia and one of interstitial pneumonia were observed. In DLBCL (n = 13) and transformed FL (n = 2) patients, OS and EFS at 3 years were 72 and 46 %, respectively. These results suggest that the MCVC regimen followed by auto-SCT is a feasible and tolerable therapy for relapsed/refractory malignant lymphoma. However, cardiac toxicity due to high-dose cyclophosphamide and development of SOS can occur and should be carefully monitored. Further follow-up is needed to evaluate the long-term efficacy and safety of this regimen