A Study Of Abnormal Coagulation And Fibrinolysis In Acute Promyelocytic Leukemia

Objective: Early hemorrhage is a significant clinical feature of acute promyelocytic leukemia(APL).Almost all patients with APL have initial laboratory evidence of increased disseminated intravascular coagulation and fibrinolysis.The most common cause of APL treatment failure was early hemorrhagic death.Unique coagulation and fibrinolysis abnormalities are closely related to early bleeding symptoms in patients with APL.By studying the correlation between early hemorrhagic symptoms and clinical observation indicators in patients with APL,it is not only conducive to the diagnosis of the disease,but also provides more basis for the treatment of the disease.Follow-up observation of changes in platelet count and coagulation and fibrinolysis index during induction therapy of different risk stratified APL patients to guide the clinical reduction of APL bleeding complications and related mortality.Methods: A total of 112 newly diagnosed APL patients were treated at Jiangsu Province Hospital from May 2009 to April 2016,including 66 males and 46 females aged 12–75 years and with a median age of 41 years.According to Sanz risk,there were 22 low-risk patients,63 intermediate-risk ones and 27 high-risk ones.All patients underwent dual induction therapy with ATO+ATRA until complete remission(CR).The obtained information included case mix(age,sex),clinical(initial bleeding events,early hemorrhagic death events,laboratory variables[white blood cell(WBC)counts,hemoglobin(HB)levels,platelet(PLT)counts,prothrombin time(PT),activated partial thromboplastin time(APTT),fbrinogen(Fbg),D-dimer(D-D),lactate dehydrogenase(LDH)and bone marrow leukemic promyelocyte(BMP)percentage].This study statistically analyzed the factors associated with bleeding symptoms in APL patients and the accompanying index characteristics of high-risk patients.This study tracked indicator trends of platelet counts,prothrombin time,activated partial thromboplastin time,fibrinogen,D-dimer during dual induction therapy in APL patients with different risk stratification.Results: Hemorrhages were the major reasons of ED,and the central nervous system(CNS)was the most common site of bleeding.The presence of bleeding symptoms correlated significantly with low platelet and fibrinogen level.The values of white blood cell,lactate dehydrogenase,prothrombin time,fibrinogen and bone marrow leukemic promyelocyte in high-risk group were significantly different from low-and intermediate-risk groups.Coagulation variables significantly improved after dual induction therapy.No significant difference were found in changes of platelet,prothrombin time,activated partial thromboplastin time,D-dimers and fibrinogen among different risk groups after induction therapy.Levels of D-dimer were initially high and remained well above normal after four weeks of induction therapy.Conclusions: Coagulation and fibrinolysis abnormalities are often present in patients with APL.Early hemorrhagic mortality remains a therapeutic challenge,and hyperfbrinolysis was a more important event in the APL hemorrhagic diathesis.Immediate dual induction therapy with ATRA and ATO is a basic measure for effective relief of coagulopathy and fibrinolysis in APL patients.Prophylactic blood transfusion maintaining high platelet and fibrinogen transfusion thresholds is an important supportive measure to reduce early bleeding in APL patients.Objective: The effect of arsenic trioxide(ATO)on fibrinolytic activity in coculture system of acute promyelocytic leukemia cell line NB4 and human umbilical vein endothelial cells(HUVEC)were explored by cell co-culture to simulate the environment in vivo.Methods: NB4,HUVEC,HL-60 cells were treated with ATO in different concentrations for 24,48 and 72 h.The effect of ATO on the proliferation of NB4,HL-60 and HUVEC cells was determined by CCK-8 assay,and the appropriate experimental concentration and time point were selected.Apoptosis of NB4,HL-60 and HUVEC cells was detected by flow cytometry(FCM)Annexin V FITC/PI double staining.NB4 and HUVEC were co-cultured for 24 h,and NB4,HUVEC cultured alone were used as controls.Protein secretion levels of tPA,PAI-1 and uPA in cultured cell supernatants of the co-culture group and the control group were measured by enzyme-linked immunosorbent assay(ELISA)before and after ATO treatment.Real-time quantitative polymerase chain reaction was used to detect the content of Annexin ? mRNA in NB4,HUVEC and co-culture groups simultaneously.Data were analyzed using SPSS statistics 16 software and significance test was performed by t test.P < 0.05 was statistically significant.Results:1.ATO inhibited the proliferation of NB4,HL-60 and HUVEC cells in a timeand dose-effect relationship.ATO promoted apoptosis in NB4,HL-60 and HUVEC cells.And NB4 was particularly sensitive to the inhibition of proliferation and apoptosis by ATO.2.NB4,HUVEC and co-culture group showed significant decrease in tPA and uPA expression after ATO treatment,while PAI-1 expression level was significantly increased(P<0.05).There was no significant difference in the expression of tPA,PAI-1 and uPA before administration.There was no significant difference in the expression of PAI-1 between each group after dosing.There was a significant difference in tPA protein levels between the co-cultured group and HUVEC cultured alone treated with ATO(P<0.05).Compared with NB4 and HUVEC cultured in ATO,the levels of uPA protein in co-culture system were significantly different(P<0.05).3.ATO treatment significantly inhibited the content of annexin ? mRNA in NB4,HUVEC and co-cultured cells(P <0.05),and the inhibition of Annexin ? mRNA content in co-culture group was particularly significant.Conclusions:ATO could inhibit the high fibrinolytic activity of APL by inhibiting the levels of tPA,uPA and Annexin ? mRNA in NB4 and HUVEC cells.2.NB4 and HUVEC co-culture might have a synergistic effect on the antifibrinolytic effect of ATO.