I型γ-分泌酶抑制剂对恶性胶质瘤细胞株增殖及凋亡的影响

Objective To investigate the role of gamma secretase inhibitor-I (GSI-I) in cell proliferation and apoptosis of human glioma cell lines U87 and U251.Methods RT-PCR and fluorescent quantitative RT-PCR (qRT-PCR) were employed to evaluate the expressions of Notch receptors and their target gene Hes-I in both U87 and U251 cells treated by GSI-I,respectively.Then,MTT assay was used to examine the effects of GSI-I on cell proliferation of the 2 glioma cells.Meanwhile,flow cytometry technique was also employed to detect the cell cycle changes and apoptosis induced by GSI-I treatment.Results The activity of Notch pathway was inhibited by GSI-I treatment through down-regulating the expression of Notch receptors target gene Hes-I in both U87 and U251 cells.Treatment with 2.5μmol/L GSI-I or above concentrations could significantly induce the cell cycle arrest of U87 and U251 cells and these effects were positively concentration-dependent.Flow cytometry technique showed that GSI-I inhibited the cell proliferation by inducing the cell cycle arrest of U87 cells at GI phase and inducing the apoptosis of U251 cells.Conclusion GSI-I can dramatically inhibit the cell proliferation and induce the apoptosis of U87 and U251 cells,providing a reliable evidence for clinical glioma treatment.     

Survivin small interfering RNA suppresses glioblastoma growth by inducing cellular apoptosis

A survivin small interfering RNA sequence specific for a human and mouse homogenous sequence was constructed.Survivin small interfering RNA could significantly inhibit glioma cell proliferation and induce apoptosis when it was transfected into either a human glioma cell line U251 or rat glioma C6 cells in vitro.In addition,treatment of rat orthotopic glioma models with survivin small interfering demonstrated the inhibition of glioma growth in vivo.Our experimental findings suggest that the use of RNA interference techniques to target the survivin sequence may be useful in the treatment of glioma.     

Survivin-specific small interfering RNAs enhance sensitivity of glioma U-87MG cells to paclitaxel by promoting apoptosis

A survivin siRNA expression vector was transfected into glioma U-87MG cells and these cells were then treated with paclitaxel.The results showed that survivin-specific siRNA combined with paclitaxel treatment synergistically inhibited glioma U-87MG cell proliferation and promoted apoptosis.This treatment also inhibited the expression of the cell cycle regulatory proteins,survivin,cyclinD1,c-Myc and CDK4 and enhanced the sensitivity of U-87MG cells to paclitaxel.     

红霉素预适应诱发胶质瘤耐药作用机制探讨

Objective To explore the effect of erythromycin preconditioning on carmustine (BCNU) resistance in glioma cell line U251 and its mechanism. Methods U251 cells was pretreated with 400 mmol/L erythromycin for 3 h followed by 30 μg/mL BCNU exposure. MTT assay and flow cytomertry were employed to detect the proliferation and apoptotic index of the cells in comparison with those of BCNU-treated U251 cells without erythromycin preconditioning and blank control cells. RT-PCR was used to detect the mRNA expressions of neuronal nitric oxide synthase (nNOS) and Bcl-2 genes in these cells. Results Compared with the BCNU treatment alone, erythromycin preconditioning prior to BCNU exposure resulted in significantly increased cell proliferation and decreased cell apoptosis (P<0.05) and upregulated the expressions of nNOS and Bcl-2 mRNAs. Conclusion Erythromycin pretreatment can induce BCNU resistance in U251 cells, and nNOS and Bcl-2 genes may play a regulatory role in this process.     

反义miR-30a-5p抑制人脑胶质瘤细胞U87生长的体外实验研究

目的 前期发现miR-30a-5p在胶质瘤中表达明显上调,本实验探究敲低miR-30a-5p对人脑胶质瘤细胞U87细胞生物学特征的影响.方法 real-time PCR检测转染miR-30a-5p I(miR-30a-5p抑制物)后U87细胞的miR-30a-5p表达水平,流式细胞术、MTT、Transwell、Annexin V法检测细胞周期、生长、侵袭及凋亡的改变;Western blot检测相关蛋白.结果 real-time PCR结果显示miR-30a-5p I可有效降低U87细胞中miR-30a-5p表达,抑制细胞增殖活性,使细胞周期阻滞在G0/G1期,侵袭能力明显受抑,凋亡增加,促增殖蛋白PCNA、促细胞周期进展蛋白Cyclin D1及促侵袭蛋白MMP-9的表达明显下调,而抑制侵袭蛋白TIMP-1及凋亡相关蛋白p53表达明显上调.结论 敲低U87细胞的miR-30a-5p表达可抑制胶质瘤的增殖及侵袭,诱导凋亡;miR-30a-5p可成为人脑胶质瘤基因治疗的潜在候选靶点.

Abstract：

Objective Our previous study had shown that there was overexpression of miR- 30a- 5p in malignant glioma cell lines.In the present study, we aim to investigate the effect of knocking -down miR -30a -5p on the biological characteristics of U87 glioblastoma cells.Method The U87 cells were divided into three groups:control cells,cells transfected with scramble oligonucleotides and cells transfected with miR -30a -5p inhibitors(miR-30a-5p I).Oligonucleotides mediated by lipofectamine were transfected to U87 cells.Real -time PCR was conducted to detect the expression of miR- 30a -5p in transfected cells.The cell proliferation was determined by 3- (4,5- Dimethylthiazol-2-yl) -2,5- diphenyltetrazolium bromide(MTT) assay and flow cytometry.The cell invasion was evaluated by Transwell assay and cell apoptosis was detected with Annexin V staining Moreover, the relevant molecules regulating proliferation, invasion, cell cycle progression and apoptosis were examined by Western blot analysis.Results The expression of miR - 30a - 5p in the cells transfected with miR - 30a - 5p I was significantly reduced.The cell proliferation activity of U87 cell was inhibited.The cell cycle was arrested in G0/G1 phase, cell invasive ability was attenuated and apoptotic cells were increased in cells transfected with miR -30a -5pI as compared to those of the cells transfected with scrambled siRNA and control cells.The expression of proliferating cell nuclear antigen (PCNA), matrix metallopeptidase 9 ( MMP - 9) and Cyclin D1 were downregulated while the tissue inhibitor of metalloproteinase1 (TIMP - 1 ) and p53 were upregulated.Conclusions Transfection of miR - 30a-5p I into glioma cells could inhibit the proliferation activity and invasive ability of U87 cell and induce cell apoptosis, miR -30a -5p is a potential target of gene therapy for glioma.     

TRAIL腺病毒增强胶质瘤对顺铂的化疗敏感性研究

目的 探讨TRAIL腺病毒增强胶质瘤对顺铂的化疗敏感性.方法 制备TRAIL腺病毒,转染胶质瘤U251,流式细胞仪和MTT法检测顺铂作用于U251细胞后各组细胞的凋亡率和增殖率.结果 本研究成功将腺病毒转染进胶质瘤U251细胞,其转染率为82.1%.TRAIL腺病毒转染胶质瘤U251 后,细胞凋亡率增加为(34.2±5.8),%细胞生长缓慢,基本上处于抑制状态.结论 TRAIL腺病毒能显著增强U251细胞对顺铂的敏感性,为胶质瘤的基因治疗提供了理论依据.

Abstract：

Objective To investigate the effect of adenovirus TRAIL on the sensitivity of glioma cells to DDP chemotherapy. Method The adenovirus TRAIL was prepared and transduced into U251 glioma cells. After DDP treatment, the apoptosis and viability of glioma cells were analyzed by FCM and MTT assays. Results The adenovirus could transduce into U251 cell with the efficiency of 82. 1 %. After adenovirus TRAIL transduction, the apoptosis rate of glioma cells was increased to ( 34. 2 ± 5. 8) % , and the cell proliferation was inhibited after DDP treatment Conclusions Adenovirus TRAIL could increase the apoptosis and sensitivity of glioma cells to chemotherapy,which may povide an ideal strategy for glioma cell gene theray.     

Transient axonal glycoprotein-1 induces apoptosis- related gene expression without triggering apoptosis in U251 glioma cells

Previous studies show that transient axonal glycoprotein-1, a ligand of amyloid precursor pro- tein, increases the secretion of amyloid precursor protein intracellular domain and is involved in apoptosis in Alzheimer＇s disease. In this study, we examined the effects of transient axonal glyco- protein-1 on U251 glioma cells. 3-（4,5-Dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide assay showed that transient axonal glycoprotein-1 did not inhibit the proliferation of U251 cells, but promoted cell viability. The terminal deoxynucleotidyl transferase dUTP nick end labeling assay showed that transient axonal glycoprotein-1 did not induce U251 cell apoptosis. Real-time PCR revealed that transient axonal glycoprotein-1 substantially upregulated levels of amyloid precursor protein intracellular C-terminal domain, and p53 and epidermal growth factor recep- tor mRNA expression. Thus, transient axonal glycoprotein-1 increased apoptosis-related gene expression in U251 cells without inducing apoptosis. Instead, transient axonal glycoprotein-1 promoted the proliferation of these glioma cells.     

Effects of selective cyclooxygenase-2 inhibitor on 36 glioma cell proliferation and apoptosis

BACKGROUND： Studies have shown that cyclooxygenase-2 is associated with proliferation and apoptosis of glioma cells. OBJECTIVE： To investigate the effects of selective cyclooxygenase-2 inhibitor celecoxib on proliferation and apoptosis of C6 glioma cells in vitro. DESIGN, TIME AND SETTING： A cellular, molecular, controlled study was performed at the Central Laboratory and Room of Electron Microscope, Medical School, Xi＇an Jiaotong University, China from March 2007 to March 2008. MATERIALS： C6 glioma cells during in vitro log phase were assigned to control and experimental groups. Celecoxib （Pfizer, USA）, dimethyl sulfoxide （Sigma, USA）, and MTT （Sigma, USA） were used for this study. METHODS： The control group was subdivided into blank control and dimethyl sulfoxide control groups. C6 glioma cells in the blank control and dimethyl sulfoxide control groups were incubated in Dulbecco＇s modified Eagle＇s medium supplemented with 10% calf serum and 0.3% dimethyl sulfoxide respectively. C6 glioma cells in the experimental group were separately treated with 60, 80 and 100 μmol/L celecoxib. MAIN OUTCOME MEASURES： Activity of C6 glioma cells was examined by MTT assay. C6 glioma cell cycle and apoptosis were determined by annexin V-fluorescein isothiocyanate/propidium iodide double-staining, followed by flow cytometry. Morphology and ultrastructure of C6 glioma cells were observed with an inverted microscope and a transmission electron microscope, respectively. RESULTS： Compared with the blank control group, cell density was reduced, adherence ability weakened, and irregular nuclei were visible, with the presence of chromatin condensation, margination, and some apoptotic bodies in the experimental group. Activity of C6 glioma cells was significantly decreased （P 〈 0.05）, cell number was reduced during S phase, cell number was significantly increased during G2/M phase （P 〈 0.01 ）, and the apoptotic rate was significantly increased （P 〈 0.05） in the experimental group. These results were displayed in a dose- and time-dependent fashion. The outcomes were obvious in the 100 IJmol/L celecoxib group following 72 hours of treatment. CONCLUSION： Celecoxib blocked proliferation and induced apoptosis of C6 glioma cells in a dose- and time-dependent fashion.     

RNA interference affects tumorigenicity and expression of insulin-like growth factor-1, insulin-like growth factor-1 receptor, and basic fibroblast growth factor-2 in rat C6 glioma cells

BACKGROUND： Human gliomas are more likely to express basic fibroblast growth factor-2 （FGF-2） insulin-like growth factor-1（IGF-1）, and IGF-1 receptor （IGF-1R） than normal brain tissue. These factors activate signal transduction systems of Ras/MAPK and PI3K/Akl, which promote glioma growth. OBJECTIVE： To utilize RNA interference （RNAi） technique to down-regulate FGF-2, IGF-1, and IGF-1R gene expression, and to investigate the effects of these genes on rat C6 glioma cells, as well as the feasibility of RNAi for treating glioma. DESIGN, TIME AND SETTING： This neurooncological, randomized, controlled, in vivo and in vitro experiment, which used RNAi methodology, was performed at the Laboratory of Molecular Biology, Institute of Biochemistry, Chinese Academy of Sciences between August 2005 and February 2008. MATERIALS： Rat C6 cell lines were purchased from Shanghai Institute of Cellular Biology Affiliated to Chinese Academy of Sciences. Small interfering RNA （siRNA） was synthesized by Shanghai GenePharma. Anti-IGF-1, anti-IGF-1R, anti-FGF-2, anti-mouse and anti-rabbit IgG G1-HRP antibodies were provided by Santa Cruz Biotechnology, USA. Four to six week-old BALB/c nude mice were purchased from the Laboratory Animal Center, Chinese Academy of Sciences. METHODS： C6 glioma cells were transfected with siRNA, which was chemically synthesized in vitro to correspond to endogenous FGF-2, IGF-1, and IGF-1R genes. The inhibition ratio of targeting mRNA expression was detected by semiquantitative RT-PCR, and protein expression was determined by Western blot analysis. C6 glioma cell proliferation was observed using a growth curve C6 glioma cell apoptosis rate and cell cycle were detected by flow cytometry. C6 glioma cell growth regression was observed by transwell migration assay. In addition, nude mouse subcutaneous tumor models were used in this study. For studying the anti-tumor effects of IGF-1 and IGF-1R siRNA, two blank control groups, with six mice each, were set up： A （2.5 μg siRNA was injected one week after C6 cells were inoculated, Le., when tumor volume reached 8 mm × 8 mm） and B （siRNA was injected at the same time with C6 cells were inoculated. To study the effects of FGF-2 siRNA, the groups consisted of a blank control group, negative control group, 2.6 μg siRNA group, 4 μg siRNA group, and 5.3 μg siRNA group, with six mice each. MAIN OUTCOME MEASURES： mRNA and protein inhibition ratio of FGF-2, IGF-1, and IGF-1 R; C6 glioma cell proliferation, apoptosis, and cycle growth arrest; C6 glioma cell growth regression and subcutaneous tumorigenicity rates. RESULTS： All siRNA constructs proved to be effective. After 48 hours, transfection of 200 nmol/L siRNA resulted in a FGF-2 or IGF-1R gene inhibition ratio 〉 80% and an IGF-1 gene inhibition ratio of approximately 70%. Protein expression levels for FGF-2, IGF-1, and IGF-1R decreased in a dose-dependent manner following siRNA transfection, with an inhibition rate 〉 85%, 60%, and 50%, respectively. C6 glioma cell proliferation and apoptosis rates increased in proportion to siRNA. The apoptosis rate of C6 glioma cells induced by FGF-2, IGF-1, and IGF-1R siRNA was 39.96%, 15.07% and 22.47%, respectively （P 〈 0.01）. Transfection of 200 nmol/L IGF or IGF-1R siRNA for 48 hours suppressed C6 glioma cell migration. At 30 days after intratumoral injection of 2.6, 4, and 5.3 tJg FGF-2 siRNA, tumor growth regression rate of FGF-2 siRNA was 56%, 67%, and 86%, respectively. The tumor growth regression rate was 71.88% and 45.71%, respectively, when IGF-1 or IGF-1R siRNA was intratumorally injected 1 week after C6 glioma cell transplantation. When IGF-1 or IGF-1 R siRNA was intratumorally injected during C6 glioma cell transplantation, the tumor growth regression rate was 78.13% and 74.29%, respectively. CONCLUSION： siRNA transfection downregulated gene expression of FGF-2, IGF-1, and IGF-1R In addition, siRNA treatment markedly suppressed glioma cell proliferation, growth, and migration, and concomitantly reduced subcutaneous tumorigenicity.     

Stem cell and precursor cell therapy

Strategies for cell replacement therapy have been guided by the success in the hematopoietic stem cell field. In this review, we discuss the basis of this success and examine whether this stem cell transplant model can be replicated in other systems where stem cell therapy is being evaluated. We conclude that identifying the most primitive stem cell and using it for transplant therapy may not be appropriate in all systems. We suggest alternative strategies such as progenitor cell replacement, inductive factors, bioengineering organs, in utero transplants, or any approach that takes advantage of the unique properties of the tissue and the stem cell type which, are more likely to provide effective functional replacement.     

Schwann细胞及糖尿病性Schwann细胞病

周围神经病是糖尿病最常见的并发症[1],其发病机理历经探索,虽有诸多发现,但迄今尚未完全明了.本病以神经元数量减少,成鞘神经纤维和Schwann细胞变性为病理特征;因此,人们在研究病变神经元的同时,也十分关注其支持细胞即Schwann细胞,并提出"糖尿病性Schwann细胞病"的观点[2].几年来,有关Schwann细胞的生理病理研究广泛而深入,现综述如下:     

Surface topography during neural stem cell differentiation regulates cell migration and cell morphology

We sought to determine the contribution of scaffold topography to the migration and morphology of neural stem cells by mimicking anatomical features of scaffolds found in vivo. We mimicked two types of central nervous system scaffolds encountered by neural stem cells during development in vitro by constructing different diameter electrospun polycaprolactone (PCL) fiber mats, a substrate that we have shown to be topographically similar to brain scaffolds. We compared the effects of large fibers (made to mimic blood vessel topography) with those of small‐diameter fibers (made to mimic radial glial process topography) on the migration and differentiation of neural stem cells. Neural stem cells showed differential migratory and morphological reactions with laminin in different topographical contexts. We demonstrate, for the first time, that neural stem cell biological responses to laminin are dependent on topographical context. Large‐fiber topography without laminin prevented cell migration, which was partially reversed by treatment with rock inhibitor. Cell morphology complexity assayed by fractal dimension was inhibited in nocodazole‐ and cytochalasin‐D–treated neural precursor cells in large‐fiber topography, but was not changed in small‐fiber topography with these inhibitors. These data indicate that cell morphology has different requirements on cytoskeletal proteins dependent on the topographical environment encountered by the cell. We propose that the physical structure of distinct scaffolds induces unique signaling cascades that regulate migration and morphology in embryonic neural precursor cells. J. Comp. Neurol. 524:3485–3502, 2016. © 2016 Wiley Periodicals, Inc.     

Stem cell reconstitution of autoimmune T cell repertoires

Maintenance of T cell memory in autoimmune disease may be complex because the unending renewable supply of self provides an inherent high antigen load that effectively precludes clearance, and because the broad array of potential immunogenic targets provides extensive self-recognition plasticity. Autoimmunity is characterized by a dynamic self-recognition process in which the primary autoreactivity initiating disease is soon followed and often displaced by secondary neoautoreactivities, or epitope spreading, that emerge as a result of endogenous self-priming. Here we show that the autoimmune disease process involves a tertiary phase of self recognition characterized by stem cell reconstitution of autoreactive T cells that recapitulates the myelin self recognition process involved in disease initiation and spreading during experimental autoimmune encephalomyelitis (EAE). Our study indicates that sustained autoimmune memory may not simply be due to the persistence of long-lived memory T cells, but may also involve bone marrow regeneration and replacement of the autoreactive T cell repertoire.     

Stem cell therapy for retinal ganglion cell degeneration

正The prospects of stem cell therapy for retinal ganglion cell(RGC)degeneration in human:RGC degeneration is a common pathologic cause of glaucoma and optic neuropathies,which are the leading cause of irreversible blindness and visual impairment in developed countries,currently affecting more than 100 million people worldwide.Intraocular pressure lowering can slow down glaucoma progression in a proportion of patients.Also,there is still no effective therapy for optic neuropathies.Besides,the degenerated RGCs in glaucoma cannot be     

Multiple cell types form the VIP amacrine cell population

Amacrine cells are a heterogeneous group of interneurons that form microcircuits with bipolar, amacrine and ganglion cells to process visual information in the inner retina. This study has characterized the morphology, neurochemistry and major cell types of a VIP-ires-Cre amacrine cell population. VIP-tdTomato and -Confetti (Brainbow2.1) mouse lines were generated by crossing a VIP-ires-Cre line with either a Cre-dependent tdTomato or Brainbow2.1 reporter line. Retinal sections and whole-mounts were evaluated by quantitative, immunohistochemical, and intracellular labeling approaches. The majority of tdTomato and Confetti fluorescent cell bodies were in the inner nuclear layer (INL) and a few cell bodies were in the ganglion cell layer (GCL). Fluorescent processes ramified in strata 1, 3, 4, and 5 of the inner plexiform layer (IPL). All tdTomato fluorescent cells expressed syntaxin 1A and GABA-immunoreactivity indicating they were amacrine cells. The average VIP-tdTomato fluorescent cell density in the INL and GCL was 535 and 24 cells/mm², respectively. TdTomato fluorescent cells in the INL and GCL contained VIP-immunoreactivity. The VIP-ires-Cre amacrine cell types were identified in VIP-Brainbow2.1 retinas or by intracellular labeling in VIP-tdTomato retinas. VIP-1 amacrine cells are bistratified, wide-field cells that ramify in strata 1, 4, and 5, VIP-2A and 2B amacrine cells are medium-field cells that mainly ramify in strata 3 and 4, and VIP-3 displaced amacrine cells are medium-field cells that ramify in strata 4 and 5 of the IPL. VIP-ires-Cre amacrine cells form a neuropeptide-expressing cell population with multiple cell types, which are likely to have distinct roles in visual processing.     

Stem cell based cell therapy for muscular dystrophy]

Stem cell-based cell therapy is one of attractive therapeutic approaches to muscular dystrophy. In transplantation into dystrophic skeletal muscle, muscle satellite cells and musclE side population (SP) cells are good candidates as sources of stem cells. We purified mouse satellite cells from adult C57B16 mice by FACS using a monoclonal antibody, SM/C-2.6, which can specifically recognize quiescent satellite cells. DNA micro-array analysis on both quiescent and activated satellite cells allowed us to distinguish novel quiescent satellite cell-specific genes. These genes may encode molecules that keep satellite cells in a dormant and undifferentiated state. We transplanted purified muscle satellite cells transduced with lentivirus vector, and found these cells were effectively incorporated into dystrophin-deficient skeletal muscle and expressed transduced dystrophin. We also identified a novel side population (SP) cells in uninjured and regenerating skeletal muscle. The majority of muscle-SP cells in uninjured stage showed endothelial cell-like properties. CD31 negative/CD45 negative SP cells were a minor population in normal conditions, but actively proliferate during muscle regeneration. Co-transplantation experiments showed that the SP cells synergistically promoted muscle regeneration with satellite cells. It is indispensable to study molecular basis of muscle stem cells and muscle regeneration to achieve effective stem cell-based cell therapy on muscular dystrophy.     

Granule cell number, cell death and cell proliferation in the dentate gyrus of wild-living rodents

Adult neurogenesis in the dentate gyrus occurs at species-specific levels. Wood mice (Apodemus flavicollis) show higher proliferation rates than laboratory mice and voles (Clethrionomys glareolus, Microtus subterraneus). We compare rates of cell death and proliferation and investigate if cell proliferation leads to the long-term recruitment of granule cells. Granule and pyknotic cell numbers were estimated in wild-living rodents in different age classes and compared with laboratory mice of mixed genetic background. All species differ significantly in their number of granule cells, except for the comparison of laboratory mice with European pine voles. Granule cell number is significantly higher in old bank voles and wood mice as compared to adults (23 and 37%, respectively). The number of pyknotic cells is highest in wood mice and lowest in laboratory mice. Across all species, the numbers of proliferating and pyknotic cells correlate. Despite differences in cell proliferation and cell death, the ratio of proliferating to pyknotic cells does not differ between adults of the wild-living species, but in laboratory mice a significantly lower proportion of cells die compared with the other species. In addition, the ratio of proliferating to pyknotic cells was significantly higher in old wood mice than in adults. We conclude (i) that cell proliferation can lead to an increase in granule cell number in wild-living rodents and (ii) that species- and age-specific changes of the ratio between proliferating and pyknotic cells occur as deviations from a close correlation of these two numbers across all species and age groups.     

Anticoagulant activity in cell homogenate of adult T cell leukemia

The hemostatic abnormality in 18 patients with adult T cell leukemia (ATL) was studied. Activated partial thromboplastin time (APTT) was slightly prolonged and prekallikrein activity was markedly low in these patients. The leukemic cell homogenate from these patients prolonged the recalcification time (RCT) of normal plasma; homogenates containing more than 3 x 10(3) cells/microliter prolonged it, although a lower cell concentration shortened it. The crude anticoagulant fraction from the gel filtration, with a molecular weight of about 34,000, prolonged RCT. The crude anticoagulant did not affect prothrombin time (PT), thrombin activity or activated X activity at any concentration, but prolonged the contact activation test, inhibited the activation of prekallikrein and prolonged RCT of Fletcher trait, Fitzgerald trait and F XII deficient plasma. These effects of ATL cell homogenate were stronger on platelet poor plasma than on platelet rich plasma. Although ATL cells had low procoagulant activity, increase of leukemic cells made anticoagulant activity predominant, might be the cause of hemostatic abnormality or amplify the bleeding tendency in patients with ATL.