Inhibition of the CXCR3-mediated pathway suppresses ultraviolet B-induced pigmentation and erythema in skin.

BACKGROUND: Skin pigmentation by ultraviolet (UV) B radiation is caused in part by inflammation mediated by chemokines and cytokines secreted by keratinocytes in the irradiated area. However, such inflammatory processes have not been well documented. OBJECTIVES: To elucidate the inflammation processes caused by UVB irradiation using skin-lightening agents that suppress melanin synthesis after UVB irradiation. METHODS: Utilizing a three-dimensional (3D) skin model, agents that suppressed formation of sunburn cells (SBC) after UVB irradiation were screened. Molecules whose expression was upregulated by UVB irradiation and attenuated by pretreatment with the agent were then screened by gene microarray to explore the mechanism of UVB irradiation. Messenger RNA expression of the molecules identified to be responsible for melanin biosynthesis was knocked down with a Tet-off shRNA lentivirus construct to confirm the involvement of the molecule in the pigmentation pathway following UVB irradiation. RESULTS: Paeonia suffruticosa Andrews (PSA) pretreatment suppressed SBC formation in the 3D skin model, and erythema formation and pigmentation in volunteers exposed to UVB irradiation. Comprehensive gene analysis after UVB irradiation showed upregulation of CXCR3 and its ligands, CXCL9/monokine induced by interferon (IFN)-γ (MIG), CXCL10/10-kDa IFN-γ-induced protein (IP-10) and CXCL11/inducible T-cell α-chemoattractant (I-TAC). Upregulation of these genes was partially suppressed by PSA pretreatment. Melanin biosynthesis increased upon stimulation of CXCR3 ligands (MIG, IP-10 or I-TAC) and decreased following CXCR3 downregulation by shRNA knockdown. CONCLUSIONS: UVB irradiation activates CXCR3-mediated signalling that leads to melanin synthesis. PSA pretreatment shows a lightening effect partly by attenuating CXCR3-mediated signalling at the transcriptional level.

Ethanol oxidation: effect on the redox state of brain in mouse.

Administration of a single large dose of ethanol to mice results in increases, for concentrations in the brain, of ratios of lactate to pyruvate, of aglycerophosphate to dihydroxyacetone phosphate, of malate to oxaloacetate, and of glutamate to the product of alpha-ketoglutarate and ammonium ion. These changes are noticed as early as 5 minutes after the single dose is given. Ethanol administration for 30 days also produces these changes in metabolite concentrations in the brain. However, in contrast to the single alcohol dose, long-term alcohol administration results in a marked decrease in the concentration of adenosine triphosphate in brain and increases in those of adenosine diphosphate and adenosine monophosphate. Pyrazole, an inhibitor of alcohol dehydrogenase, prevents the effects of ethanol on the concentration of brain metabolites. These results may provide new insight into the biochemical and pharmacological effects of alcohol on brain metabolism and the importance of alcohol dehydrogenase activity in the brain.

L-glutamic acid decarboxylase: a new type in glial cells and human brain gliomas.

Human glial cells grown in culture and gliomas and white matter contain an l-glutamic acid decarboxylase which is stimulated markedly by carbonyl-trapping agents. In contrast, L-glutamic acid decarboxylase activity of human cerebral gray matter is strongly inhibited by carbonyl-trapping agents. These results suggest a glial localization of the new type of l-glutamic acid decarboxylase.

Description of International Caenorhabditis elegans Experiment first flight (ICE-FIRST).

Traveling, living and working in space is now a reality. The number of people and length of time in space is increasing. With new horizons for exploration it becomes more important to fully understand and provide countermeasures to the effects of the space environment on the human body. In addition, space provides a unique laboratory to study how life and physiologic functions adapt from the cellular level to that of the entire organism. Caenorhabditis elegans is a genetic model organism used to study physiology on Earth. Here we provide a description of the rationale, design, methods, and space culture validation of the ICE-FIRST payload, which engaged C. elegans researchers from four nations. Here we also show C. elegans growth and development proceeds essentially normally in a chemically defined liquid medium on board the International Space Station (10.9 day round trip). By setting flight constraints first and bringing together established C. elegans researchers second, we were able to use minimal stowage space to successfully return a total of 53 independent samples, each containing more than a hundred individual animals, to investigators within one year of experiment concept. We believe that in the future, bringing together individuals with knowledge of flight experiment operations, flight hardware, space biology, and genetic model organisms should yield similarly successful payloads.

Cloning of the ALL-1 fusion partner, the AF-6 gene, involved in acute myeloid leukemias with the t(6;11) chromosome translocation.

Reciprocal chromosome translocations involving 11q23 are frequently associated with acute leukemias, with the t(4;11) translocation predominating among acute lymphoblastic leukemias, and the t(9;11), t(11;19) and t(6;11) translocations most common among acute myeloid leukemias. In each of these translocations the ALL-1 gene, located at 11q23 and constituting the human homologue of Drosophila trithorax, fuses to a specific gene on the partner chromosome to produce a chimeric protein. Here we report the cloning and the characterization of the partner gene from chromosome 6 (AF-6). AF-6 is expressed in a variety of cell types and encodes a protein of 1612 amino acids. The protein contains short stretches rich in prolines, charged amino acids, serines, or glutamines. In addition, the AF-6 protein contains the GLGF motif shared with several proteins of vertebrates and invertebrates thought to be involved in signal transduction at special cell-cell junctions.

Characterization of cerebellar guanylate cyclase using N-methyl-N'-nitro-N-nitrosoguanidine. Presence of two different types of guanylate cyclase in soluble and particulate fractions.

Some characteristics of guanylate cyclase (GTP pyrophosphate-lyase (cyclizing), EC 4.6.1.2) in subcellular fractions prepared from rat cerebellum have been analyzed on the basis of responsiveness to N-methyl-N'-nitro-N-nitrosoguanidine and inhibitors related to N-nitroso compounds. The enzyme in 100 000 X g supernatant and crude mitochondrial (P2) fractions were differently activated (11- and 2.5-fold, respectively) by N-methyl-N'-nitro-N-nitrosoguanidine. The soluble fraction obtained by hypo-osmotic treatment and subsequent recentrifugation of the P2 (P2-soluble) contained a significantly higher total guanylate cyclase activity than that of the starting material (P2). The P2-soluble fraction also exhibited a lower responsiveness (1.5-fold) to N-methyl-N'-nitro-N-nitrosoguanidine than that found in the P2. The membrane fraction prepared from the P2 (P2-membrane) had no response to N-methyl-N'-nitro-N-nitrosoguanidine. Hemoglobin and vitamin A derivatives significantly inhibited both N-methyl-N'-nitro-N-nitrosoguanidine-activated 100 000 X g supernatant and basal P2-soluble enzyme activities, without effect on the basal activities in 100 000 X g supernatant and P2-membrane fractions. The present results suggest that two different types of guanylate cyclase may be present in rat cerebellum in terms of the responsiveness of N-nitroso compounds, and P2-soluble guanylate cyclase seems to be activated endogenously through a mechanism similar to the action of N-methyl-N'-nitro-N-nitrosoguanidine.

Characteristics of taurine transport system and its developmental pattern in mouse cerebral cortical neurons in primary culture.

Developmental patterns and pharmacological and biochemical properties of taurine transport system were investigated using developing primary cultured neurons prepared from mouse cerebral cortex by trypsin treatment. [3H]Taurine was incorporated into neurons via a high-affinity transport system of which the Km value as well as the Vmax value increased during neuronal development in vitro. This transport system was also inhibited by sodium withdrawal from incubation medium and exposures for 15 h to several metabolic inhibitors such as 2,4-dinitrophenol and monoiodoacetate. In addition, [3H]taurine uptake in both neurons cultured for 3 and 14 days was competitively inhibited by beta-alanine, guanidinoethanesulfonate and hypotaurine. Cysteic acid and cysteine sulfinic acid, metabolic intermediates produced in the process of taurine biosynthesis in the brain from cysteine, induced significant reductions in [3H]taurine uptake in both types of cultured neurons, while cysteine, isethionic acid, cysteamine and cystamine exhibited no alterations in [3H]taurine transport. Moreover, non-competitive inhibition of [3H]taurine uptake by cysteic acid was observed in both neurons. These results clearly indicate that taurine uptake was mediated by the sodium- and energy-dependent transport system with high affinity in 14-day-old neurons as well as neurons cultured for 3 days and that both the Km and Vmax values of this transport system increase during neuronal development in vitro. The results described above suggest that the decrease in taurine content observed in developing brain is unlikely to be due to alteration in the capacity of the taurine transport system during neuronal development.

Requirement for etoposide in the treatment of Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis.

PURPOSE: We sought to identify the clinical variables most critical to successful treatment of Epstein-Barr virus (EBV)-associated hemophagocytic lymphohistiocytosis (HLH). PATIENTS AND METHODS: Among the factors tested were age at diagnosis (< 2 years or > or = 2 years), time from diagnosis to initiation of treatment with or without etoposide-containing regimens, timing of cyclosporin A (CSA) administration during induction therapy, and the presence or absence of etoposide. RESULTS: By Kaplan-Meier analysis, the overall survival rate for the entire cohort of 47 patients, most of whom had moderately severe to severe disease, was 78.3% +/- 6.7% (SE) at 4 years. The probability of long-term survival was significantly higher when etoposide treatment was begun less than 4 weeks from diagnosis (90.2% +/- 6.9% v 56.5% +/- 12.6% for patients receiving this agent later or not at all; P <.01, log-rank test). Multivariate analysis with the Cox proportional hazards model demonstrated the independent prognostic significance of a short interval from EBV-HLH diagnosis to etoposide administration (relative risk of death for patients lacking this feature, 14.1; 95% confidence interval, 1.16 to 166.7; P =.04). None of the competing variables analyzed had significant predictive strength in the Cox model. However, concomitant use of CSA with etoposide in a subset of patients appears to have prevented serious complications from neutropenia during the first year of treatment. CONCLUSION: We conclude that early administration of etoposide, preferably with CSA, is the treatment of choice for patients with EBV-HLH.

Human urinary macrophage colony-stimulating factor reduces the incidence and duration of febrile neutropenia and shortens the period required to finish three courses of intensive consolidation therapy in acute myeloid leukemia: a double-blind controlled study.

PURPOSE: To determine whether macrophage colony-stimulating factor (M-CSF) reduces the incidence and duration of febrile neutropenia during three courses of intensive consolidation therapy and whether it shortens time to complete consolidation therapy. PATIENTS AND METHODS: In 198 adult patients with acute myeloid leukemia (AML) in complete remission (CR), M-CSF (8 x 10(6) U/d) or placebo was administered from 1 day after the end of each consolidation chemotherapy for 14 days. RESULTS: The duration and incidence of febrile neutropenia was significantly reduced by 34% (P = .00285) and 17% (P = .02065), respectively, in 88 assessable patients in the M-CSF group compared with those in 94 assessable patients in the placebo group. Patients in the M-CSF group had 565 days and 133 episodes of febrile neutropenia during 7,901 days at risk, while patients in the placebo group had 977 days and 185 episodes during 9,077 days at risk. The median period required to finish the three courses of consolidation therapy was 93 days in the M-CSF group, which was significantly shorter than 110 days in placebo group (P = .0050). In the M-CSF group, the recovery of neutrophils and platelets was significantly faster (P = .0348 and P = 0.0364, respectively), the administration of systemic antimicrobial agents tended to be less (P = .0839), and the frequency of platelet transfusion (P = .0259) and the total volume of transfused platelets (P = .0292) were significantly less. However, there was no significant difference in the disease-free survival. CONCLUSION: M-CSF significantly reduced the incidence and duration of febrile neutropenia during the intensive consolidation therapy, and shortened the time to complete consolidation chemotherapy in AML.

Analysis of prognostic factors in newly diagnosed acute promyelocytic leukemia treated with all-trans retinoic acid and chemotherapy. Japan Adult Leukemia Study Group.

PURPOSE: We conducted a multicenter study of differentiation therapy with all-trans retinoic acid (ATRA) followed by intensive chemotherapy in patients with newly diagnosed acute promyelocytic leukemia (APL) and analyzed the prognostic factors for predicting complete remission (CR), event-free survival (EFS), and disease-free survival (DFS). PATIENTS AND METHODS: All patients received ATRA until CR. If patients had an initial leukocyte count greater than 3.0 x 10(9)/L, they received daunorubicin (DNR) and behenoyl cytarabine (BHAC). During therapy, if patients showed blast and promyelocyte counts greater than 1.0 x 10(9)/L, they received additional DNR and BHAC. After achieving CR, patients received three courses of consolidation and six courses of maintenance/intensification chemotherapy. RESULTS: Of 198 registered, 196 were assessable (age range, 15 to 86 years; median, 46) and 173 (88%) achieved CR. Multivariate analysis showed that no or minor purpura at diagnosis (P = .0046) and age less than 30 years (P = .0076) were favorable factors for achievement of CR. Predicted 4-year overall survival and EFS rates were 74% and 54%, respectively, and the 4-year predicted DFS rate for 173 CR patients was 62%. Multivariate analysis showed that age less than 30 years (P = .0003) and initial leukocyte count less than 10 x 10(9)/L (P = .0296) were prognostic factors for longer EFS, and initial leukocyte count less than 10.0 x 10(9)/L was a sole significant prognostic factor for longer DFS (P = .0001). CONCLUSION: Our results show that age, hemorrhagic diathesis, and initial leukocyte count are prognostic factors for APL treated with ATRA followed by intensive chemotherapy.

Randomized trials between behenoyl cytarabine and cytarabine in combination induction and consolidation therapy, and with or without ubenimex after maintenance/intensification therapy in adult acute myeloid leukemia. The Japan Leukemia Study Group.

PURPOSE: We analyzed complete remission (CR), disease-free survival (DFS), and event-free survival (EFS) rates in two groups of patients treated with either N4-behenoyl-1-beta-D-arabinosylcytosine (BHAC) or cytarabine, and analyzed DFS with or without ubenimex, a biologic response modifier. PATIENTS AND METHODS: Newly diagnosed patients with acute myeloid leukemia (AML) were randomized to receive either BHAC or cytarabine as remission-induction combination chemotherapy and two courses of consolidation therapy. After maintenance/intensification therapy, patients in CR were randomized to receive either ubenimex and no drug. RESULTS: Of 341 patients registered, 326 were assessable. The age of assessable patients ranged from 15 to 82 years (median, 48). The overall CR rate was 77%: 72% in the BHAC group and 81% in the cytarabine group, and there was a significant difference between the two groups (P = .035, chi 2 test). The predicted 55-month EFS rate of all patients was 30%: 23% in the BHAC group and 35% in the cytarabine group, with a significant difference between groups (P = .0253). The predicted 55-month DFS rate of all CR patients was 38% and that of CR patients less than 50 years of age was 47%. There was no significant difference in DFS between the ubenimex group and the group that did not receive ubenimex. CONCLUSION: Analyses of our clinical trial showed that the use of BHAC in remission-induction therapy and in consolidation therapy resulted in poorer CR and EFS rates in adult AML patients compared with the use of cytarabine at the doses and schedules tested. Immunotherapy with ubenimex after the end of all chemotherapy did not improve DFS.

Colony-forming unit-megakaryocyte (CFR-meg) numbers and serum thrombopoietin concentrations in thrombocytopenic disorders: an inverse correlation in myelodysplastic syndromes.

We studied both serum-free colony-forming unit-megakaryocyte (CFU-meg) numbers and serum thrombopoietin (TPO) levels in 14 patients with aplastic anemia (AA), 37 patients with myelodysplastic syndromes (MDS) and 23 patients with idiopathic thrombocytopenic purpura (ITP) to assess thrombopoiesis in these thrombocytopenic disorders. The mean CFU-meg numbers were lower in AA and MDS patients (10.7 +/- 11.4 and 42.3 +/- 58.5/10(5) BMLD cells) than in healthy controls (103.1 +/- 57.3/10(5) BMLD cells) (P < 0.0001 and P= 0.0053, respectively), although they were distributed variably in MDS. ITP patients showed higher CFU-meg numbers (223.2 +/- 143.5/10(5) BMLD cells) (P= 0.017). The mean TPO concentrations were higher in both AA (986.8 +/- 500.8 pg/ml) and MDS patients (838.2 +/- 639.1 pg/ml) than in healthy controls (80.7 +/- 38.8 pg/ml) (P < 0.0001), although they were distributed from high to low in MDS. ITP patients showed a slight elevation of TPO (123.1 +/- 55.3 pg/ml) P = 0.0106). The TPO levels was inversely correlated to both platelet counts and CFU-meg numbers (correlative coefficient (CC): -0.719 and -0.682, P < 0.0001) in AA, but not in ITP. In MDS, the inverse correlation to TPO was stronger in CFU-meg (CC: -0.678, P < 0.0001) than in platelet counts (CC: -0.538, P = 0.0014), suggesting that CFU-meg plays an important role in regulating TPO production in this heterogenous disorder. CFU-meg and TPO may provide useful information for understanding thrombopoiesis of MDS, especially for application of TPO.

Effect of a selective Abl tyrosine kinase inhibitor, STI571, on in vitro growth of BCR-ABL-positive acute lymphoblastic leukemia cells.

By employing a new semi-quantitative assay system that includes co-culturing leukemia cells with the mouse bone marrow-derived stromal cell line MS-5, we examined the suppressive effect of a selective inhibitor of ABL tyrosine kinase, STI571, on acute lymphoblastic leukemia (ALL) cells with BCR-ABL fusion. Leukemic blast cells from eight patients with B-precursor ALL, including three patients with BCR-ABL-positive ALL, were cultured on monolayers of MS-5 cells for 3 weeks with or without addition of variable amounts of STI571. In all cases, cobblestone areas (CAs) were formed, showing clear linear cell dose-dependent curves, allowing quantitative assessment of blast cell growth. The progenitor frequencies obtained by this direct CA-forming cell (CAFC) assay were equivalent to ALL progenitor frequencies assessed by the standard limiting dilution assay. The number of CAFCs ranged from 12.3 to 140.3/10(4) cells. In BCR-ABL-positive ALL patients, CA-containing cells were examined by FISH, and all contained BCR-ABL fusion genes. STI571 inhibited CA formation of BCR-ABL-positive ALL cells virtually 100% at 0.1-1.0 micromol/l. None of the five BCR-ABL-negative ALL patients showed this growth inhibition by STI571 at 0.1-1.0 micromol/l. Our results indicate that STI571 selectively inhibits in vitro growth of BCR-ABL-positive ALL cells.

Establishment and characterization of a new erythropoietin-dependent acute myeloid leukemia cell line, AS-E2.

We have established an erythropoietin-dependent human leukemia cell line, AS-E2, from a patient with acute myeloid leukemia. These cells have many characteristics of late erythroid progenitor cells, they are positive for CD36, Glycophorin A, and CD71 but negative for CD41, and positive for benzidine and PAS staining. These cells express GATA-1 and have low affinity erythropoietin (EPO) receptor on their surface. Interestingly, AS-E2 cells are strictly dependent on EPO for their growth and survival; other cytokines including GM-CSF, stem cell factor, or IL-3 cannot support the growth of this cell line. These features are similar to late erythroid lineage cells, like normal BFU-E or CFU-E, and we have demonstrated that EPO stimulation induces the tyrosine phosphorylation of several proteins in AS-E2 cells including the EPO receptor and JAK2 kinase. This new cell line is a useful reagent to study biological and molecular events during the late stages of erythropoiesis, and to understand transforming events in human erythroid cells.

Allogeneic bone marrow transplantation improves the outcome of de novo AML with trilineage dysplasia (AML-TLD).

De novo acute myeloid leukemia (AML) with dysplastic features in erythroblasts, granulocytes and megakaryocytes, similar to those in myelodysplastic syndrome (MDS) has been described as AML with trilineage dysplasia (AML-TLD) since 1987. Several reports have suggested that AML-TLD is a subtype of de novo AML in adults and has a poor clinical outcome when treated by conventional chemotherapy. It is not certain whether allogeneic bone marrow transplantation (BMT) brings a favorable outcome for AML-TLD. To evaluate the therapeutic efficacy of allogeneic BMT for AML-TLD, we investigated the clinical data and outcomes of conventional chemotherapy and allogeneic BMT for 118 patients with de novo AML. These patients were registered consecutively for the Japan Adult Leukemia Study Group (JALSG) protocols at our institutes. We treated 28 AML-TLD patients and 90 AML-nonTLD patients with conventional chemotherapeutic protocols. AML-TLD patients did not have a significantly different complete remission (CR) rate (75.0% and 88.4% P = 0.1234), but had a significantly higher relapse rate than AML-nonTLD patients (94.1% and 49.3%, P= 0.0007). The outcome of chemotherapy for AML-TLD was significantly worse than that for AML-nonTLD. The overall survival (OS) and leukemia-free survival (LFS) at 6 years were 9.4% and 0% in AML-TLD group, and 51.9% (P= 0.0017) and 46.3% (P< 0.0001) in AML-nonTLD group, respectively. Meanwhile, among the patients who underwent allogeneic BMT, five of eight AML-TLD patients and eight of 14 AML-nonTLD patients were alive, and three and five patients survived more than 3 years, respectively. These results suggest that allogeneic BMT can improve the outcome for AML-TLD, which is poor when conventional chemotherapy is given alone. Allogeneic BMT before relapse may be the best therapeutic strategy for AML-TLD patients under 50 years of age if a donor is available.

The percentage of myeloperoxidase-positive blast cells is a strong independent prognostic factor in acute myeloid leukemia, even in the patients with normal karyotype.

To examine whether the percentage of myeloperoxidase (MPO)-positive blast cells is useful as a prognostic factor for acute myeloid leukemia (AML), cytochemical analysis of MPO was performed in 491 patients who were registered to the Japan Adult Leukemia Study Group-AML92 study. Patients were divided into two using the percentage of MPO-positive blast (high [>or=50%] and low (<50%)). Complete remission rates were 85.4% in the former and 64.1% in the latter (P=0.001). The overall survival (OS) and the disease-free survival (DFS) were significantly better in the high MPO group (48.3 vs 18.7% for OS, and 36.3 vs 20.1% for DFS, P<0.001, respectively). Multivariate analysis showed that both karyotype and the percentage of MPO-positive blast cells were equally important prognostic factors. The high MPO group still showed a better survival even when restricted to the intermediate chromosomal risk group or the patients with normal karyotype (P<0.001). The OS of patients with normal karyotype in the high MPO group was almost equal with that of the favorable chromosomal risk group. The percentage of MPO-positive blast cells is a simple and highly significant prognostic factor for AML patients, and especially useful to stratify patients with normal karyotype.

All-trans retinoic acid therapy in relapsed/refractory or newly diagnosed acute promyelocytic leukemia (APL) in Japan.

We have conducted four prospective multicenter studies for acute promyelocytic leukemia (APL) using oral 45 mg/m2 all-trans retinoic acid (ATRA) daily. The first three studies were for relapsed/refractory APL, and the fourth study for newly diagnosed APL. In the first study with ATRA alone, 18 (82%) of 22 evaluable patients achieved complete remission (CR). Initial peripheral leukemia cell counts were significantly less in the CR cases (p < 0.01); < 100/microliters in 17 of 18 CR cases, and > or = 200/microliters in all failure cases. In the second study, if initial leukemia cell counts were more than 200/microliters, chemotherapy with daunorubicin and behenoyl cytarabine was first given, and then ATRA was started. Of 42 evaluable patients, 36 (86%) achieved CR. In the third study, if initial leukemia cell counts were more than 200/microliters, chemotherapy was concomitantly given with ATRA, and if during the ATRA therapy leukemia cell counts became more than 1000/microliters, chemotherapy was added. Of 46 evaluable patients, 36 (78%) achieved CR. Patients achieving CR received standard consolidation and maintenance chemotherapy, and the 29-month predicted disease-free survival (DFS) rate is 72% for 41 cases achieving their first CR with ATRA, and 20% for 49 cases achieving their second CR with ATRA. In the fourth study for newly diagnosed APL, if leukocyte counts were more than 3000/microliters, chemotherapy was concomitantly given with ATRA, and if during the ATRA therapy leukemia cell counts became more than 1000/microliters, chemotherapy was added. Of 109 evaluable patients, 97 (89%) achieved CR, and the 19-month predicted event-free survival rate for all patients is 78%, and the DFS rate is 88% for 97 cases achieving CR. ATRA produces a high CR rate in both relapsed/refractory and newly diagnosed APL, and should be incorporated in the first-line therapy of this disease.

New system for assessing the prognosis of refractory anemia patients.

Refractory anemia (RA) is a very heterogeneous disease regarding biological and clinical features. The International Prognostic Scoring System (IPSS) was useful for assessing the prognosis in the whole group of 219 myelodysplastic syndrome (MDS) patients. However, the IPSS was not sufficient in 132 RA patients. To predict survival and freedom from acute myeloid leukemia (AML) evolution, we investigated individual prognostic factors based on the clinical parameters (age, gender, morphologic features, cytopenias and cytogenetics) of 132 RA patients using univariate and multivariate analyses. Based on the results, we devised a new system for assessing the prognosis of RA patients. In our system, RA patients with pseudo-Pelger-Huët anomalies >/=3% were classified as high risk (12 patients); of patients without pseudo-Pelger-Huët anomalies >/=3%, those with intermediate/poor karyotype according to IPSS, Hb /=10% were classified as intermediate risk (57 patients); and those without high or intermediate risk were classified as low risk (67 patients). In our system, the analyses of both survival times and leukemia-free survival times revealed significant differences among the three groups (P < 0.0001).

Morphological subtyping of acute myeloid leukemia with maturation (AML-M2): homogeneous pink-colored cytoplasm of mature neutrophils is most characteristic of AML-M2 with t(8;21).

Morphologic and cytochemical features of 30 acute myeloid leukemia subtype M2 (AML-M2) patients with t(8;21) were compared with those of 50 AML-M2 patients without t(8;21). It was disclosed that irregular nuclear shape, Auer bodies, and at least 90% myeloperoxidase positivity in blast cells, and pseudo-Pelger-Huët anomaly of the nuclei and homogeneous pink-colored cytoplasm of mature neutrophils were observed in 90-100% of the t(8;21)+ patients. The percentages of patients showing these features were significantly (P < 0.01) lower in the t(8;21)- group. Among these morphological features, homogeneous pink-colored cytoplasm of mature neutrophils is most characteristic of t(8;21)+ AML-M2, because it was seen in 90% of the t(8;21)+ patients but in only 2% of the t(8;21)- patients. Conversely, pale-colored cytoplasm without any granules in mature neutrophils or dyserythropoietic features was observed in 84% of the t(8;21)- patients, but in none of the t(8;21)+ patients. These data suggest that it is possible to subtype AML-M2 patients morphologically by the recognition of homogeneous pink-colored or pale-colored cytoplasm of mature neutrophils and dyserythropoietic features. Thus, the morphologic subtyping of AML-M2 can be utilized alone or in combination with chromosomal or molecular subtyping for biological and clinical studies of AML with maturation.

Prognostic significance of the null genotype of glutathione S-transferase-T1 in patients with acute myeloid leukemia: increased early death after chemotherapy.

We investigated the prognostic significance of genetic polymorphism in glutathione-S transferase mu 1 (GSTM1), glutathione-S transferase theta 1 (GSTT1), NAD(P)H:quinone oxidoreductase (NQO1) and myeloperoxidase (MPO), the products of which are associated with drug metabolism as well as with detoxication, in 193 patients with de novo acute myeloid leukemia (AML) other than M3. Of the patients, 64.2% were either homozygous or heterozygous for GSTT1 (GSTT1(+)), while 35.8% showed homozygous deletions of GSTT1 (GSTT1(-)). The GSTT1(-) group had a worse prognosis than the GSTT1(+) group (P = 0.04), whereas other genotypes did not affect the outcome. Multivariate analysis revealed that GSTT1(-) was an independent prognostic factor for overall survival (relative risk: 1.53; P = 0.026) but not for disease-free survival of 140 patients who achieved complete remission (CR). The rate of early death after the initiation of chemotherapy was higher in the GSTT1(-) group than the GSTT1(+) group (within 45 days after initial chemotherapy, P = 0.073; within 120 days, P = 0.028), whereas CR rates and relapse frequencies were similar. The null genotype of GSTT1 might be associated with increased toxicity after chemotherapy.