BACKGROUND Therapy-related acute promyelocytic leukemia(t-APL)is a rare complication observed in solitary bone plasmacytoma(SBP),and SBP after radiotherapy evolving to APL harboring the FMS-like tyrosine kinase 3-inte...BACKGROUND Therapy-related acute promyelocytic leukemia(t-APL)is a rare complication observed in solitary bone plasmacytoma(SBP),and SBP after radiotherapy evolving to APL harboring the FMS-like tyrosine kinase 3-internal tandem duplication(FLT3-ITD)mutation has never been reported.Here,we present the first case reported until now.CASE SUMMARY We describe a 64-year-old woman who presented with lumbar pain and was initially diagnosed with SBP.However,after one year of radiotherapy treatment,this patient experienced a long-standing bone-marrow-suppressive period and finally developed APL harboring the FLT3-ITD mutation,as confirmed by analyses of clinical features,bone marrow morphology,flow cytometry,cytogenetic examination,and molecular biology.On admission,the patient had disseminated intravascular coagulation and intracranial hemorrhage,and the peripheral blood and bone marrow smear displayed abundant abnormal promyelocytes.Unfortunately,she died when the definite diagnosis was made.CONCLUSION The patient with t-APL harboring FLT3-ITD mutation evolving from SBP after radiotherapy had not been reported and had poor clinical outcomes.FLT3-ITD mutation in t-APL may be a potential pathogenesis of leukemogenesis.We should consider the potential risk of secondary neoplasms in SBP patients after radiotherapy.展开更多
Rabies is a zoonotic disease that still causes 59,000 human deaths each year,and rabies vaccine is the most effective way to control the disease.Our previous studies suggested that the maturation of DC plays an import...Rabies is a zoonotic disease that still causes 59,000 human deaths each year,and rabies vaccine is the most effective way to control the disease.Our previous studies suggested that the maturation of DC plays an important role in enhancing the immunogenicity of rabies vaccine.Flt3L has been reported to own the ability to accelerate the DC maturation,therefore,in this study,a recombinant rabies virus expressing mouse Flt3L,designated as LBNSE-Flt3L,was constructed,and its immunogenicity was characterized.It was found that LBNSE-FU3L could enhance the maturation of DC both in vitro and in vivo,and significantly more TFH cells and Germinal Center B(GC B)cells were generated in mice immunized with LBNSE-FU3L than those immunized with the parent virus LBNSE.Consequently,expressing of Flt3L could elevate the level of virus-neutralizing antibodies(VNA)in immunized mice which provides a better protection from a lethal rabies virus challenge.Taken together,our study extends the potential of Flt3L as a good adjuvant to develop novel rabies vaccine by enhancing the VNA production through activating the DC—Tfh^GC B axis in immunized mice.展开更多
Dendritic cells （DCs） are immune cells specialized to capture, process and present antigen to T cells in order to initiate an appropriate adaptive immune response. The study of mouse DC has revealed a heterogeneous ...Dendritic cells （DCs） are immune cells specialized to capture, process and present antigen to T cells in order to initiate an appropriate adaptive immune response. The study of mouse DC has revealed a heterogeneous population of cells that differ in their development, surface phenotype and function. The study of human blood and spleen has shown the presence of two subsets of conventional DC including the CDlb/c＋ and CD141＋CLEC9A＋ conventional DC （cDC） and a plasmacytoid DC （pDC） that is CD304＋CD123＋. Studies on these subpopulations have revealed phenotypic and functional differences that are similar to those described in the mouse. In this study, the three DC subsets have been generated in vitrofrom human CD34＋ precursors in the presence of fins-like tyrosine kinase 3 ligand （FIt3L） and thrombopoietin （TPO）. The DC subsets so generated, including the CDlb/c＋ and CLEC9A＋ cDCs and CD123 ＋ pDCs, were largely similar to their blood and spleen counterparts with respect to surface phenotype, toll-like receptor and transcription factor expression, capacity to stimulate T cells, cytokine secretion and cross-presentation of antigens. This system may be utilized to study aspects of DC development and function not possible in vivo.展开更多
All-trans retinoic acid(ATRA)and pre-upfront arsenic trioxide(ATO)have revolutionized the therapy of acute promyelocytic leukemia(APL).However,internal tandem duplication of FMS-like tyrosine kinase 3(FLT3-ITD)mutatio...All-trans retinoic acid(ATRA)and pre-upfront arsenic trioxide(ATO)have revolutionized the therapy of acute promyelocytic leukemia(APL).However,internal tandem duplication of FMS-like tyrosine kinase 3(FLT3-ITD)mutations is associated with increased risk of relapse.The aim of this study was to analyze the prognostic impact of FLT3-ITD on APL patients who received remission induction with ATRA,idarubicin(IDA)and/or ATO,followed by ATRA plus ATO along with anthracycline,as consolidation therapy.A total of 72 patients newly diagnosed with APL were included in this study.83.3%of the patients achieved complete remission(CR)after induction therapy.FLT3-ITD mutations were detected in 16(22.2%)patients and closely related to bcr-3 PML-RARa transcript(P<0.001).The 5-year overall survival(OS)rate was 100%in both FLT3-ITDposltlve and FLT3-ITD^(negatlve)groups,and there was no significant difference in 5-year event-free survival(EFS)between the two groups(78.3%vs.83.3%,P=0.85).ATRA plus ATO and anthracycline-based chemotherapy achieved great outcome in newly diagnosed APL regardless of the FLT3-ITD mutation status.展开更多
FMS-like tyrosine kinase 3(FLT3) is classified as a type Ⅲ receptor tyrosine kinase, which exerts a key role in regulation of normal hematopoiesis. FLT3 mutation is the most common genetic mutation in acute myeloid l...FMS-like tyrosine kinase 3(FLT3) is classified as a type Ⅲ receptor tyrosine kinase, which exerts a key role in regulation of normal hematopoiesis. FLT3 mutation is the most common genetic mutation in acute myeloid leukemia(AML) and represents an attractive therapeutic target. Targeted therapy with FLT3 inhibitors in AML shows modest promising results in current ongoing clinical trials suggesting the complexity of FLT3 targeting in therapeutics. Importantly, resistance to FLT3 inhibitors may explain the lack of overwhelming response and could obstruct the successful treatment for AML. Here, we summarize the molecular mechanisms of primary resistance and acquired resistance to FLT3 inhibitors and discuss the strategies to circumvent the emergency of drug resistance and to develop novel treatment intervention.展开更多
基金Natural Science Foundation of Zhejiang Province,No.LY19H290003Zhejiang Provincial Medical and Health Science and Technology Project,No.2020KY196and Foundation of Zhejiang Province Chinese Medicine Science and Technology Planes,No.2017ZB030.
文摘BACKGROUND Therapy-related acute promyelocytic leukemia(t-APL)is a rare complication observed in solitary bone plasmacytoma(SBP),and SBP after radiotherapy evolving to APL harboring the FMS-like tyrosine kinase 3-internal tandem duplication(FLT3-ITD)mutation has never been reported.Here,we present the first case reported until now.CASE SUMMARY We describe a 64-year-old woman who presented with lumbar pain and was initially diagnosed with SBP.However,after one year of radiotherapy treatment,this patient experienced a long-standing bone-marrow-suppressive period and finally developed APL harboring the FLT3-ITD mutation,as confirmed by analyses of clinical features,bone marrow morphology,flow cytometry,cytogenetic examination,and molecular biology.On admission,the patient had disseminated intravascular coagulation and intracranial hemorrhage,and the peripheral blood and bone marrow smear displayed abundant abnormal promyelocytes.Unfortunately,she died when the definite diagnosis was made.CONCLUSION The patient with t-APL harboring FLT3-ITD mutation evolving from SBP after radiotherapy had not been reported and had poor clinical outcomes.FLT3-ITD mutation in t-APL may be a potential pathogenesis of leukemogenesis.We should consider the potential risk of secondary neoplasms in SBP patients after radiotherapy.
基金supported by the National Program on Key Research Project of China (2016YFD0500400 and 2017YFD0501701)the National Natural Science Foundation of China (31872494, 31402176, 31372419, and 31522057)+2 种基金the Fundamental Research Funds for the Central Universities (No. 2662016QD036 to MZ)the Ministry of Science and Technology of China (863 program, No. 2011AA10A212)the Ministry of Agriculture of China (Special Fund for Agro-scientific Research in the Public Interest, No. 201303042 to ZFF)
文摘Rabies is a zoonotic disease that still causes 59,000 human deaths each year,and rabies vaccine is the most effective way to control the disease.Our previous studies suggested that the maturation of DC plays an important role in enhancing the immunogenicity of rabies vaccine.Flt3L has been reported to own the ability to accelerate the DC maturation,therefore,in this study,a recombinant rabies virus expressing mouse Flt3L,designated as LBNSE-Flt3L,was constructed,and its immunogenicity was characterized.It was found that LBNSE-FU3L could enhance the maturation of DC both in vitro and in vivo,and significantly more TFH cells and Germinal Center B(GC B)cells were generated in mice immunized with LBNSE-FU3L than those immunized with the parent virus LBNSE.Consequently,expressing of Flt3L could elevate the level of virus-neutralizing antibodies(VNA)in immunized mice which provides a better protection from a lethal rabies virus challenge.Taken together,our study extends the potential of Flt3L as a good adjuvant to develop novel rabies vaccine by enhancing the VNA production through activating the DC—Tfh^GC B axis in immunized mice.
文摘Dendritic cells （DCs） are immune cells specialized to capture, process and present antigen to T cells in order to initiate an appropriate adaptive immune response. The study of mouse DC has revealed a heterogeneous population of cells that differ in their development, surface phenotype and function. The study of human blood and spleen has shown the presence of two subsets of conventional DC including the CDlb/c＋ and CD141＋CLEC9A＋ conventional DC （cDC） and a plasmacytoid DC （pDC） that is CD304＋CD123＋. Studies on these subpopulations have revealed phenotypic and functional differences that are similar to those described in the mouse. In this study, the three DC subsets have been generated in vitrofrom human CD34＋ precursors in the presence of fins-like tyrosine kinase 3 ligand （FIt3L） and thrombopoietin （TPO）. The DC subsets so generated, including the CDlb/c＋ and CLEC9A＋ cDCs and CD123 ＋ pDCs, were largely similar to their blood and spleen counterparts with respect to surface phenotype, toll-like receptor and transcription factor expression, capacity to stimulate T cells, cytokine secretion and cross-presentation of antigens. This system may be utilized to study aspects of DC development and function not possible in vivo.
文摘All-trans retinoic acid(ATRA)and pre-upfront arsenic trioxide(ATO)have revolutionized the therapy of acute promyelocytic leukemia(APL).However,internal tandem duplication of FMS-like tyrosine kinase 3(FLT3-ITD)mutations is associated with increased risk of relapse.The aim of this study was to analyze the prognostic impact of FLT3-ITD on APL patients who received remission induction with ATRA,idarubicin(IDA)and/or ATO,followed by ATRA plus ATO along with anthracycline,as consolidation therapy.A total of 72 patients newly diagnosed with APL were included in this study.83.3%of the patients achieved complete remission(CR)after induction therapy.FLT3-ITD mutations were detected in 16(22.2%)patients and closely related to bcr-3 PML-RARa transcript(P<0.001).The 5-year overall survival(OS)rate was 100%in both FLT3-ITDposltlve and FLT3-ITD^(negatlve)groups,and there was no significant difference in 5-year event-free survival(EFS)between the two groups(78.3%vs.83.3%,P=0.85).ATRA plus ATO and anthracycline-based chemotherapy achieved great outcome in newly diagnosed APL regardless of the FLT3-ITD mutation status.
基金Supported by the Singapore National Research Foundation and the Ministry of Education under the Research Center of Excellence Program(to Chng WJ)NMRC Clinician-Scientist IRG Grant,No.CNIG11nov38(to Zhou J)+1 种基金supported by NMRC Clinician Scientist Investigator awardsupported by the RNA Biology Center at CSI Singapore,NUS,from funding by the Singapore Ministry of Education’s Tier 3 grants,No.MOE2014-T3-1-006
文摘FMS-like tyrosine kinase 3(FLT3) is classified as a type Ⅲ receptor tyrosine kinase, which exerts a key role in regulation of normal hematopoiesis. FLT3 mutation is the most common genetic mutation in acute myeloid leukemia(AML) and represents an attractive therapeutic target. Targeted therapy with FLT3 inhibitors in AML shows modest promising results in current ongoing clinical trials suggesting the complexity of FLT3 targeting in therapeutics. Importantly, resistance to FLT3 inhibitors may explain the lack of overwhelming response and could obstruct the successful treatment for AML. Here, we summarize the molecular mechanisms of primary resistance and acquired resistance to FLT3 inhibitors and discuss the strategies to circumvent the emergency of drug resistance and to develop novel treatment intervention.
