Search

Background aims Predicting autologous peripheral blood stem cell (PBSC) collection yield before leukapheresis is important for optimizing PBSC mobilization and autologous stem cell transplantation (ASCT) for treating hematological malignancies. Although guidelines for plerixafor usage based on peripheral blood CD34+ (PB-CD34+) cell count are available, their predictive performance in the real world remains unclear. Methods This study retrospectively analyzed 55 mobilization procedures for patients with non-Hodgkin lymphoma or multiple myeloma and developed a novel quantitative prediction model for CD34+ cell collection yield that incorporated four clinical parameters available the day before leukapheresis; namely, PB-CD34+ cell count the day before apheresis (day -1 PB-CD34+), number of prior chemotherapy regimens, disease status at apheresis and mobilization protocol. Results The effects of PB-CD34+ cell counts on CD34+ cell collection yield varied widely per patient characteristics, and plerixafor usage was recommended in patients with poorly controlled disease or those with a history of heavy pre-treatments even with abundant day -1 PB-CD34+ cell count. This model suggested a more proactive use of plerixafor than that recommended by the guidelines for patients with poor pre-collection condition or those with a higher target number of CD34+ cells. Further, the authors analyzed the clinical outcomes of ASCT and found that plerixafor use for stem cell mobilization did not affect short- or long-term outcomes after ASCT. Conclusions Although external validations are necessary, the results can be beneficial for establishing more effective and safer mobilization strategies.

Aim: Posterior circulation stroke (PCS) has different clinical features and prognosis compared with anterior circulation stroke (ACS), and whether the effect of statin therapy on stroke prevention differs according to infarction location remains unclear. This post hoc analysis of the J-STARS study aimed to compare the usefulness of statin at different infarction locations (i.e., ACS and PCS). Methods: In the J-STARS study, 1578 patients were randomly assigned to the pravastatin or control group. The subjects were divided into two subgroups (ACS and PCS groups) based on the arteries responsible for the infarction. Cox proportional hazards models were used to investigate whether the all stroke recurrence rate was different between the ACS and PCS groups. Results: The PCS group (n = 499) had a significantly higher prevalence of diabetes than the ACS group (n = 1022) (30.7% vs. 19.8%, P < 0.001). During the follow-up (4.9 ± 1.4 years), the incidence of all stroke was significantly lower in the pravastatin group than in the control group among patients with PCS (adjusted hazard ratio [HR] 0.46, 95% confidence interval [CI] 0.25–0.83, P = 0.009); however, the stroke recurrence rates were not significantly different between both groups among patients with ACS (adjusted HR 1.32, 95% CI 0.93–1.88, P = 0.123). A significant interaction between the ACS and PCS groups in terms of pravastatin effects was noted (P = 0.003 for interaction). Conclusions: Pravastatin significantly reduced the recurrence rate of all stroke among patients with PCS. Thus, the effect of statin on the recurrence of stroke may differ according to infarction location.

Aims To understand the different influences of statins on the incidence rate of each stroke subtype in association with low-density lipoprotein (LDL) cholesterol levels, we performed a post hoc analysis on the data from the Japan Statin Treatment Against Recurrent Stroke (J-STARS) study. Methods Subjects (n=1,578) were divided into three groups according to their mean postrandomized LDL cholesterol level (＜100, 100-120, and ≥ 120 mg/dL) until the last observation before the event or the end of follow-up. A Cox proportional hazard model for time to events was used for calculating adjusted hazard ratios, 95% confidence intervals, and the trend tests. Results The event rates for atherothrombotic stroke did not decrease in accordance with the postrandomized LDL cholesterol level subgroups of either the control or the pravastatin group (p=0.15 and 0.33 for the trend, respectively). In the control group, however, no atherothrombotic stroke event was observed in the subgroup of the low postrandomized LDL cholesterol level (less than 100 mg/dL). The event rates for atherothrombotic stroke were lower in the middle postrandomized LDL cholesterol level subgroup (100-120 mg/dL) of the pravastatin group than that of the control group. The event rates for lacunar stroke decreased in the lower postrandomized LDL cholesterol level subgroup of the control group but not of the pravastatin group (p=0.004 and 0.06 for the trend, respectively). Conclusions Statins showed different influences on the risks of atherothromobotic and lacunar stroke according to postrandomized LDL cholesterol levels.

Granulocyte transfusion (GTX) is a therapeutic option for severe bacterial or fungal infection in patients with sustained neutropenia after chemotherapy or stem cell transplantation. However, high molecular weight hydroxyethyl starch (HES), which has been used for selective sedimentation of red blood cells during apheresis, is not easily available in many countries including Japan. In this study, we evaluated the efficiency of granulocyte collection using medium molecular weight HES (130 kDa) in combination with the Spectra Optia apheresis system. Apheresis was performed for 2 consecutive days from seven donors and the mean total neutrophil yield from the first and second apheresis was 5.27 ± 3.10 × 1010 and 2.91 ± 2.92 × 1010, respectively. Infusion of concentrates from the first apheresis resulted in a significant neutrophil count increase and concentrates from the second apheresis were enough for maintenance of the neutrophil counts in all the recipients. Although the number of cases is limited, our results clearly show that sufficient number of granulocytes can be harvested by using medium molecular weight HES and this strategy is a safe and effective clinical practice in countries where high molecular weight HES is not available.

Aims: The J-STARS study examined whether pravastatin (10 mg/day) reduces recurrence of stroke in non-cardioembolic ischemic stroke patients who were enrolled within 1 month to 3 years after initial stroke events (ClinicalTrials.gov, NCT00221104). The main results showed that the frequency of atherothrombotic stroke was low in pravastatin-treated patients, although no effect of pravastatin was found for the other stroke subtypes. We evaluated differences of early (within 6 months) or late (after 6 months) pravastatin treatment benefits on the incidence of stroke or transient ischemic attack (TIA), as well as atherothrombotic stroke and the other subtypes. Methods: Subjects in the J-STARS study were classified into two cohorts, depending on whether they enrolled early (1 to 6 months) or late (6 months to 3 years) following initial stroke events. Results: A total of 1578 patients (491 female, 66.2 ± 8.5 years) were randomly assigned to either the pravastatin group (n = 793; n = 426 in the early cohort, n = 367 in the late cohort) or the control group (n = 785; n = 417 in the early cohort, n = 368 in the late cohort). During the follow-up of 4.9 ± 1.4 years, the rate of atherothrombotic stroke was lower in the pravastatin group compared to controls in the early cohort (0.24 vs. 0.88%/year, p = 0.01) but not in the late cohort (0.17 vs. 0.39%/year, p = 0.29). However, this difference of pravastatin effect on atherothrombotic stroke was not significantly interacted by the early or late cohort (p = 0.59). The incidence rates of other stroke subtype were not different in between pravastatin and control groups despite the timing of entry. Conclusions: Pravastatin is likely to reduce atherothrombotic stroke in patients enrolled within 6 months after stroke onset. However, the clinical efficacy for prevention of recurrent stroke was not conclusive with earlier statin treatment.

The emergence of new molecular targeting agents has improved the prognosis of patients with multiple myeloma (MM). However, MM remains incurable because MM stem cells are likely resistant to these agents. Thus, it is important to further investigate the biology of MM stem cells, which reside in the hypoxic bone marrow niche. In this study, we established and investigated the characteristics of hypoxia-adapted MM (HA-MM) cells, which could proliferate for more than six months under hypoxic conditions (1% O2). The G0 fraction of HA-MM cells was larger than that of parental MM cells under normoxic conditions (20% O2). HA-MM cells possess enhanced tumorigenicity in primary and secondary transplantation studies. HA-MM cells also exhibited increased mRNA levels of stem cell markers and an enhanced self-renewal ability, and thus demonstrated characteristics of MM stem cells. These cells overexpressed phosphorylated Smad2, and treatment with a transforming growth factor (TGF)-β/Smad signaling inhibitor decreased their clonogenicity in a replating assay. In conclusion, MM cells adapted to long-exposure of hypoxia exhibit stem cell characters with TGF-β/Smad pathway activation.

Background Efficacy of adjuvant chemotherapy in patients with stage II colon cancer is still controversial. The SACURA trial is a randomised-controlled study evaluating the superiority of 1-year adjuvant treatment with oral tegafur–uracil (UFT) to surgery alone for stage II colon cancer. Methods Patients were randomly assigned to the surgery-alone group or UFT group (UFT at 500–600 mg/day for 5 days, followed by 2-day rest, for 1 year). The primary end-point was disease-free survival (DFS). Target sample size was 2000, determined with one-sided alpha of 0.05, power of 0.9 and assumed hazard ratio (HR) 0.729. Results A total of 1982 patients (997 in the surgery-alone group and 985 in the UFT group) were analysed. Median follow-up was 69.5 months, median age was 66 years and for stage IIA/IIB/IIC, the distribution was 84%/13%/3%. The 5-year DFS rate was 78.4% in the surgery-alone group and 80.2% in the UFT group. The HR for DFS was 0.91 (95% confidence interval [CI], 0.75–1.10; p = 0.31); superiority of UFT was not demonstrated. Approximately 9% of patients experienced second cancers, which consist 40.7% of the DFS events. The 5-year relapse-free and overall survival rates of the surgery-alone and UFT group were 84.6% and 87.2% (HR, 0.82; 95% CI, 0.65–1.04) and 94.3% and 94.5% (HR, 0.93; 95% CI, 0.66–1.31), respectively. Subgroup analysis failed to disclose superiority in prognosis of adding UFT to the patients with risk factors for recurrence. Conclusions Superiority of 1-year adjuvant UFT over surgery alone was not demonstrated in stage II colon cancer. Patients with risk factors for recurrence did not benefit from UFT. Trial registration ClinicalTrials. Gov. # NCT00392899 .

Background and Purpose— To define desirable target low-density lipoprotein (LDL) cholesterol levels for the prevention of stroke recurrence, a post hoc analysis was performed in the J-STARS study (Japan Statin Treatment Against Recurrent Stroke). Methods— Subjects (n=1578) were divided into groups based on mean value of postrandomized LDL cholesterol levels until the last observation in 20 mg/dL increments. Adjusted hazard ratios (HRs) and 95% confidence intervals were analyzed for each group, with adjustments for baseline LDL cholesterol, baseline body mass index, hypertension, diabetes mellitus, and statin usage. Results— The postrandomized LDL cholesterol level until the last observation were 104.1±19.3 mg/dL in the pravastatin group and 126.1±20.6 mg/dL in the control group. The adjusted HRs for stroke and transient ischemic attack and all vascular events decreased in the postrandomized LDL cholesterol level of 80 to 100 mg/dL ( P =0.23 and 0.25 for the trend, respectively). The adjusted HR for atherothrombotic infarction significantly reduced with the usage of statin after adjusting baseline LDL cholesterol levels (HR, 0.39; 95% confidence intervals, 0.19–0.83). The adjusted HR for atherothrombotic infarction and intracranial hemorrhage were similar among the postrandomized LDL-cholesterol–level subgroups ( P =0.50 and 0.37 for the trend, respectively). The adjusted HR for lacunar infarction decreased in the postrandomized LDL cholesterol level of 100 to 120 mg/dL (HR, 0.45; 95% confidence intervals, 0.20–0.99; P =0.41 for the trend). Conclusions— The composite risk of stroke and transient ischemic attack reduced in the postrandomized LDL cholesterol level of 80 to 100 mg/dL after adjusting for statin usage. Clinical Trial Registration— URL: http://www.clinicaltrials.gov . Unique identifier: NCT00221104.

Cyclooxygenase (COX) is a key rate-limiting enzyme for prostaglandin (PG) production cascades in the human body. The mechanisms of both the anti-inflammation effects and the side-effects of traditional COX inhibitors are associated with the existence of two COX isoforms. Thus while COX-1 is predominantly expressed ubiquitously and constitutively, and it serves a housekeeping role in processes such as gastrointestinal (GI) mucosa protection, COX-2 is absent or exhibits a low level of expression in most tissues, and is highly upregulated in response to endotoxin, virus, inflammatory or tissue-injury stimuli/signals, and tumour promoter in the various types of organs, tissues, and cells. Furthermore, COX-2 contribution to PGE2 and PGI2 production evokes and sustains systemic or peripheral inflammatory disease, but it is not involved in the COX-1-mediated GI tract events. Also, hypersensitivity of aspirin owing to its inhibitory action against COX-1 is a significant concern clinically. Consequently, highly selective COX-2 inhibitors have been needed for the treatment of inflammatory- and inflammation related-diseases that include pyrexia, inflammation, pain, rheumatoid arthritis, osteoarthritis, and cancers. In this study, a series of novel [2-{[(4-substituted or 4,5-disubstituted)-pyridin-2-yl]carbonyl}-(5- or 6-substituted or 5,6-disubstituted)-1H-indol-3-yl]acetic acid analogues was designed, synthesized, and evaluated to identify potent and selective COX-2 inhibitors as potential agents against inflammatory diseases. As significant findings, the present study clarified unique structure–activity relationship of the analogues toward potent and selective COX-2 inhibition in vitro, and identified 2-{6-fluoro-2-[4-methyl-2-pridinyl)carbonyl]-1H-indol-3-yl}acetic acid as a potent and selective COX-2 inhibitor in vitro that demonstrated orally potent anti-inflammation efficacy against carrageenan-induced oedema formation in the foot of SPF/VAF male SD rats as a peripheral inflammation model in vivo.

Treatment with Abl tyrosine kinase inhibitors (TKI) drastically improves the prognosis of chronic myelogenous leukemia (CML) patients. However, quiescent CML cells are insensitive to TKI and can lead to relapse of the disease. Thus, research is needed to elucidate the properties of these quiescent CML cells, including their microenvironment, in order to effectively target them. Hypoxia is known to be a common feature of solid tumors that contributes to therapeutic resistance. Leukemic cells are also able to survive and proliferate in severely hypoxic environments. The hypoxic conditions in the bone marrow (BM) allow leukemic cells that reside there to become insensitive to cell death stimuli. To target leukemic cells in hypoxic conditions, we focused on the hypoxia-selective cytotoxin, Rakicidin A. A previous report showed that Rakicidin A, a natural product produced by the Micromonospora strain, induced hypoxia-selective cytotoxicity in solid tumors. Here, we describe Rakicidin A-induced cell death in hypoxia-adapted (HA)-CML cells with stem cell-like characteristics. Interestingly, apoptosis was induced via caspase-dependent and -independent pathways. In addition, treatment with Rakicidin A in combination with the TKI, imatinib, resulted in synergistic cytotoxicity against HA-CML cells. In conclusion, Rakicidin A is a promising compound for targeting TKI-resistant quiescent CML stem cells in the hypoxic BM environment. (Cancer Sci 2011; 102: 591–596)

Purpose: β-catenin is the downstream effector of the Wnt signaling pathway, and it regulates cell proliferation. β-catenin overexpression correlates positively with prognosis in several types of malignancies. We herein assessed its effects on growth of multiple myeloma cells using a xenograft model. Experimental Design: We first investigated the expression of β-catenin in multiple myeloma cell lines and multiple myeloma cells obtained from patients. Next, we investigated the growth inhibitory effects of β-catenin small interfering RNA on the growth of multiple myeloma cells in vivo. Six-week-old male BALB/c nu/nu mice were inoculated s.c. in the right flank with 5 × 106 RPMI8226 cells, followed by s.c. injections of β-catenin small interfering RNA, scramble small interfering RNA, or PBS/atelocollagen complex twice a week for a total of eight injections. Results: Significantly higher levels of β-catenin expression were observed in multiple myeloma cell lines and in samples from patients with multiple myeloma than those found in mononuclear cells obtained from healthy volunteers. In in vivo experiments, no inhibitory effects were observed following treatment with scramble small interfering RNA or PBS/atelocollagen complexes, whereas treatment with β-catenin small interfering RNA/atelocollagen complex significantly inhibited growth of multiple myeloma tumors (P < 0.05). Conclusions: β-catenin small interfering RNA treatment inhibited the growth of multiple myeloma tumors in a xenograft model. To our knowledge, this is the first report showing that the treatment with β-catenin small interfering RNA produces an inhibitory effects on growth of hematologic malignancies in vivo. Because treatment with β-catenin small interfering RNA inhibited growth of multiple myeloma cells, β-catenin is the attractive novel target for treating multiple myeloma.

Existence of an endothelio-endothelial placenta is controversial. Insectivores may have a placenta of this type or the endothelio-chorial type; thus, studies of the placentae of Suncus murinus, the laboratory shrew, were undertaken. Cellular components of the interhemal membrane included maternal endothelium, intermediate trophoblast (syncytiotrophoblast) and fetal endothelium. Up to day 20 of gestation, the intermediate trophoblast clearly intervened between the hypertrophied maternal endothelium and the fetal endothelium throughout the labyrinthine zone. From day 20 to 24, the intermediate trophoblast was sieve-like in appearance with extensive infoldings at both surfaces. Basal laminae of both the maternal endothelium and the intermediate trophoblast were broad, irregular and continuous. Therefore, at this stage the placenta was endothelio-chorial in type. After day 24 of gestation, the intermediate trophoblast could scarcely be recognized as an obvious and continuous layer. Only cytoplasmic processes of the intermediate trophoblast were present between the maternal and the fetal endothelium. Finally, projections of both the maternal and the fetal endothelium contacted each other. We conclude that the intermediate trophoblast does not play a central role within the placental barrier throughout the last week of gestation. Hence, the placenta of Suncus murinus is endothelio-endothelial in type.

Allograft inflammatory factor (AIF)-1 has been identified in chronic rejection of rat cardiac allografts and is thought to be involved in the immune response. We previously showed that AIF-1 was strongly expressed in synovial tissues in rheumatoid arthritis and that rAIF-1 increased the IL-6 production of synoviocytes and peripheral blood mononuclear cells. Recently, the expression of AIF-1 has been reported in systemic sclerosis (SSc) tissues, whose clinical features and histopathology are similar to those of chronic graft-vs-host disease (GVHD). To clarify the pathogenic mechanism of fibrosis, we examined the expression and function of AIF in sclerodermatous (Scl) GVHD mice. We demonstrated that immunoreactive AIF-1 and IL-6 were significantly expressed in infiltrating mononuclear cells and fibroblasts in thickened skin of Scl GVHD mice compared with control. The immunohistochemical findings were confirmed by Western blot analysis. Wound healing assay also revealed that rAIF-1 increased the migration of normal human dermal fibroblasts (NHDF) directly, but cell growth assay did not show that rAIF-1 increased the proliferation of them. These findings suggest that AIF-1, which can induce the migration of fibroblasts and the production of IL-6 in affected skin tissues, is an important molecule promoting fibrosis in GVHD. Although the biological function of AIF-1 has not been completely elucidated, AIF-1 can induce IL-6 secretion on mononuclear cells and fibroblast chemotaxis. AIF-1 may accordingly provide an attractive new target for antifibrotic therapy in SSc as well as Scl GVHD.

PURPOSE: Brain radiation necrosis (BRN) is a serious adverse event of radiotherapy especially for malignant brain tumors such as glioma and cancer metastasis, which can deteriorate the quality of life in the patients. Since vascular endothelial growth factor is a forcible vascular permeability factor highly expressed in BRN, bevacizumab is expected be an alternative treatment to reduce its perilesional edema. We performed a prospective, multicenter, single-arm trial involving patients with symptomatic BRN to evaluate the safety and efficacy of bevacizumab. PATIENTS AND METHODS: Patients with surgically untreatable symptomatic BRN refractory to conventional treatments (e.g. corticosteroid, anti-coagulants, or hyperbaric oxygen therapy) were enrolled. We judged that a major cause of perilisional edema was BRN, not tumor recurrence, when lesion/normal brain ratio showed ≤ 1.8 or ≤ 2.5 on 11C-methionine and 18 F-boronophenylalanine positron emission tomography (PET), respectively. 5mg/kg of bevacizumab was administrated 6 cycles biweekly. ≥30% reduction of perilesional edema lasting at least one month was specified as the primary endpoint. RESULTS: Forty-one patients were enrolled in this trial. The primary endpoint was achieved in 30 out of 38 (78.9%) patients at 3.03 months (median) after enrollment. Sixteen patients (42.1%) experienced improvement of Karnofsky performance status. Corticosteroid could be reduced in 29 patients (76.3%). Adverse events with grade ≥3 occurred in 10 patients (24.4%). CONCLUSION: Bevacizumab treatment offers certain clinical benefits for patients with surgically untreatable symptomatic BRN. The determination using amino acid PET, not biopsy, is valid and less invasive for eligibility to administrate bevacizumab.

The prognosis of patients with multiple myeloma (MM) has been improved by the emergence of new molecular targeting agents including proteasome inhibitors and immunomodurating agents. Nevertheless, MM remains incurable at present because it is likely that MM stem cells are resistant to these targeting agents. Thus, it is important to further investigate the biology of MM stem cells to cure the MM patients. We have demonstrated that b-catenin is a novel and attractive target against MM (Ashihara et al. Clin Cancer Res, 2009; Yao et al. Blood Cancer J, 2011). We next investigate novel targets focused on the hypoxic bone marrow (BM) environment. BM is known to have low levels of oxygen, particularly at the epiphysis, which is distant form the BM arterial blood supply. Normal hematopoietic stem cells (HSCs) reside in this hypoxic epiphyseal region “niche”, and HSCs are protected from DNA damage induced by reactive oxygen species. We have previously found that chronic myelogenous leukemia (CML) cells engrafted in the BM survived and proliferated in the severely hypoxic environment and that these hypoxia-adapted (HA) leukemic cells acquired stem cell-like characters (Takeuchi et al. Cell Death Differ, 2010). In this study, we investigated the characteristics of hypoxia-adapted MM (HA-MM) cells. We first confirmed oxygen status in the BM of the MM cell-engrafted mice. Irradiated NOD/SCID mice were inoculated with 2 x 106 AMO-1 cells. After 2 or 4 weeks transplantation, we sacrificed mice and confirmed engraftment. The inoculated MM cells engrafted in the epiphysis in recipient mice after 2 weeks transplantation, and populated endosteum of epiphysis after 4 weeks. These MM cells were positive for pimonidazole, which specifically accumulated in hypoxic cells (< 1.3% O2 concentration). These observations suggested that MM cells resided in the BM are hypoxic. We then established AMO-1, OPM-2, and IM-9 HA-MM cells cultured under hypoxic conditions (O2 1%). These HA cells can continue to proliferate in hypoxic conditions for more than six months. In flow cytometric analysis, the G0 fraction cells as well as side population fraction cells significantly increased in HA-MM cells compared with those in the parental MM cells. We next transplanted parental or HA-MM AMO-1 cells with same cell numbers into irradiated NOD/SCID mice. The survival durations of mice transplanted with HA-AMO-1 cells were significantly shorter than that of mice transplanted with parental cells. Moreover, in serial transplantation experiments, all 5 HA-MM cell-transplanted mice died of MM whereas 1 out of 5 parental MM cell-transplanted mice (Figure 1). Quantitative RT-PCR analysis demonstrated that Sox2, Oct3, and Nanog mRNA transcripts increased in the HA-MM AMO-1 cells (Figure 2). We next investigated the signaling pathway activated in HA-MM cells. Interestingly, phosphorylated Smad2 expression was increased in HA-AMO-1 cells. These findings suggest that HA-MM cells possess stem cell-like character, and these cells may provide a useful model to investigate the mechanism of MM stem cells (myeloma-initiating cells) resistant to molecular target agents. Disclosures: No relevant conflicts of interest to declare.