Modern therapy of acute myeloid leukemia(AML)began in 1973 with the first report of the successful combination of daunorubicin and cytarabine,which led to complete remission in approximately 45%of patients.Accurate AM...Modern therapy of acute myeloid leukemia(AML)began in 1973 with the first report of the successful combination of daunorubicin and cytarabine,which led to complete remission in approximately 45%of patients.Accurate AML diagnosis was dependent on morphology,aided initially only by cytochemistry.Unlike acute lymphoblastic leukemia(ALL),immunophenotyping offered little in the diagnosis of AML,at least during the 1970s and 1980s.The advent of reliable cytogenetics changed the entire prognostic outlook of AML.With karyotypic analysis,different groups of AML could be classified and stratified for various therapies.Unique mutational profiling was a major advance in further categorizing AML patients,aided by the immunophenotypic identification of antigenic markers on the cells.All these advances were occurring as the understanding of the importance of the tumor burden—known as minimal residual disease(MRD)—became crucial for the management of AML patients.The efficacy of MRD has rapidly progressed in the past decade,from a specificity of 103 with immunophenotyping to 104 with polymerase chain reaction(PCR),which is only appropriate for some patients with AML,and finally to 105 or even 106 cells with the extraordinary sensitivity of next-generation sequencing(NGS).All of these advances have promoted the concept of personalized medicine,which has led to the advent of targeted agents that can accurately be used for specific diagnostic subtypes.Responses can be predicted and measured accurately.Such targeted agents have now become a cornerstone in the management of AML,increasing effi-cacy and dramatically reducing toxicity.The focus of this review is on one of the most well-studied targeted agents in AML:the FMS-like tyrosine kinase 3(FLT3)inhibitors,which have impacted the prognostication and therapeutics of AML.This review selectively discusses the FLT3 inhibitors in detail,as a model for the other burgeoning targeted agents that have already been approved,as well as those that are currently in development.展开更多
目的:探讨双吲哚马来酰亚胺衍生物GZWM-051诱导人白血病HEL细胞凋亡的作用及机制。方法:分别使用不同浓度的GZWM-051处理HEL细胞,采用MTT法测定HEL细胞的存活率,计算抑制率及 IC 50 值;采用Hoechst 33258染色观察处理HEL细胞24 h时的凋...目的:探讨双吲哚马来酰亚胺衍生物GZWM-051诱导人白血病HEL细胞凋亡的作用及机制。方法:分别使用不同浓度的GZWM-051处理HEL细胞,采用MTT法测定HEL细胞的存活率,计算抑制率及 IC 50 值;采用Hoechst 33258染色观察处理HEL细胞24 h时的凋亡现象,采用流式细胞术检测处理HEL细胞24及48 h时细胞凋亡水平,Western blot法检测处理HEL细胞24 h时细胞凋亡蛋白表达水平。结果: GZWM-051能抑制HEL细胞的增殖活性,显著提高其凋亡率( P <0.01);Western blot结果显示,0.050 μmol/L或0.100 μmol/LGZWM-051处理HEL细胞后,其Bcl-2蛋白表达水平显著下调( P <0.01),Caspase-3剪切体表达水平显著上调( P <0.01)。结论: GZWM-051可能是通过下调抗凋亡蛋白Bcl-2表达水平和激活Caspase-3剪切体水平诱导HEL细胞凋亡。展开更多
FMS-related tyrosine kinase 3(FLT3)mutations,present in about 25%-30%of acute myeloid leukemia(AML)patients,constitute one of the most frequently detected mutations in these patients.The binding of FLT3L to FLT3 activ...FMS-related tyrosine kinase 3(FLT3)mutations,present in about 25%-30%of acute myeloid leukemia(AML)patients,constitute one of the most frequently detected mutations in these patients.The binding of FLT3L to FLT3 activates the phosphatidylinositol 3-kinase(PI3K)and RAS pathways,producing increased cell proliferation and the inhibition of apoptosis.Two types of FLT3 mutations exist:FLT3-ITD and FLT3-TKD(point mutations in D835 and I836 or deletion of codon I836).A class of drugs,tyrosine-kinase inhibitors(TKI),targeting mutated FLT3,is already available with 1st and 2nd generation molecules,but only midostaurin and gilteritinib are currently approved.However,the emergence of resistance or the selection of clones not responding to FLT3 inhibitors has become an important clinical dilemma,as the duration of clinical responses is generally limited to a few months.This review analyzes the insights into mechanisms of resistance to TKI and poses a particular view on the clinical relevance of this phenomenon.Has resistance been overlooked?Indeed,FLT3 inhibitors have significantly contributed to reducing the negative impact of FLT3 mutations on the prognosis of AML patients who are no longer considered at high risk by the European LeukemiaNet(ELN)2022.Finally,several ongoing efforts to overcome resistance to FLT3-inhibitors will be presented:new generation FLT3 inhibitors in monotherapy or combined with standard chemotherapy,hypomethylating drugs,or IDH1/2 inhibitors,Bcl2 inhibitors;novel anti-human FLT3 monoclonal antibodies(e.g.,FLT3/CD3 bispecific antibodies);FLT3-CAR T-cells;CDK4/6 kinase inhibitor(e.g.,palbociclib).展开更多
Introduction:Mastocytosis,a clonal proliferation of mast cells commonly involving the skin and bone marrow,has a varied clinical presentation ranging from cutaneous lesions to systemic disease.Cutaneous mastocytosis i...Introduction:Mastocytosis,a clonal proliferation of mast cells commonly involving the skin and bone marrow,has a varied clinical presentation ranging from cutaneous lesions to systemic disease.Cutaneous mastocytosis is managed symptomatically,but systemic mastocytosis is treated with targeted therapy against the mutated receptor tyrosine kinase c-KIT,the pathogenic driver of mastocytosis.However,there are no guidelines for the treatment of cutaneous mastocytosis refractory to symptomatic management.We herein report a method to select genetically informed therapy for symptomatic and recalcitrant cutaneous mastocytosis.Case presentation:We performed a mutational analysis of dermal mast cells after enrichment by laser capture in a 23-year-old woman with recalcitrant cutaneous mastocytosis.The analysis revealed a aspartic acid to valine substitution at codon 816(D816V)mutation in the protein c-KIT.Based on these results,we initiated treatment with the multi-kinase/KIT inhibitor midostaurin,a treatment effective against the D816V c-KIT mutation.After 3 months of treatment,the patient exhibited a reduction in the number and size of cutaneous lesions and reported resolution of pruritus and decreased severity of other mast cell-related symptoms.Discussion:The treatment of mastocytosis relies heavily on whether the disease is limited to the skin or systemic.However,there are no guidelines for cutaneous mastocytosis that does not respond to symptomatic management.In the present report describing a patient with recalcitrant cutaneous mastocytosis,we describe a strategy in which skin mutational analysis is used to guide the selection of targeted therapy.Conclusion:Performing mast cell mutational analyses in the skin provides a means to select targeted therapy for symptomatic and refractory cutaneous mastocytosis.展开更多
文摘Modern therapy of acute myeloid leukemia(AML)began in 1973 with the first report of the successful combination of daunorubicin and cytarabine,which led to complete remission in approximately 45%of patients.Accurate AML diagnosis was dependent on morphology,aided initially only by cytochemistry.Unlike acute lymphoblastic leukemia(ALL),immunophenotyping offered little in the diagnosis of AML,at least during the 1970s and 1980s.The advent of reliable cytogenetics changed the entire prognostic outlook of AML.With karyotypic analysis,different groups of AML could be classified and stratified for various therapies.Unique mutational profiling was a major advance in further categorizing AML patients,aided by the immunophenotypic identification of antigenic markers on the cells.All these advances were occurring as the understanding of the importance of the tumor burden—known as minimal residual disease(MRD)—became crucial for the management of AML patients.The efficacy of MRD has rapidly progressed in the past decade,from a specificity of 103 with immunophenotyping to 104 with polymerase chain reaction(PCR),which is only appropriate for some patients with AML,and finally to 105 or even 106 cells with the extraordinary sensitivity of next-generation sequencing(NGS).All of these advances have promoted the concept of personalized medicine,which has led to the advent of targeted agents that can accurately be used for specific diagnostic subtypes.Responses can be predicted and measured accurately.Such targeted agents have now become a cornerstone in the management of AML,increasing effi-cacy and dramatically reducing toxicity.The focus of this review is on one of the most well-studied targeted agents in AML:the FMS-like tyrosine kinase 3(FLT3)inhibitors,which have impacted the prognostication and therapeutics of AML.This review selectively discusses the FLT3 inhibitors in detail,as a model for the other burgeoning targeted agents that have already been approved,as well as those that are currently in development.
文摘目的:探讨双吲哚马来酰亚胺衍生物GZWM-051诱导人白血病HEL细胞凋亡的作用及机制。方法:分别使用不同浓度的GZWM-051处理HEL细胞,采用MTT法测定HEL细胞的存活率,计算抑制率及 IC 50 值;采用Hoechst 33258染色观察处理HEL细胞24 h时的凋亡现象,采用流式细胞术检测处理HEL细胞24及48 h时细胞凋亡水平,Western blot法检测处理HEL细胞24 h时细胞凋亡蛋白表达水平。结果: GZWM-051能抑制HEL细胞的增殖活性,显著提高其凋亡率( P <0.01);Western blot结果显示,0.050 μmol/L或0.100 μmol/LGZWM-051处理HEL细胞后,其Bcl-2蛋白表达水平显著下调( P <0.01),Caspase-3剪切体表达水平显著上调( P <0.01)。结论: GZWM-051可能是通过下调抗凋亡蛋白Bcl-2表达水平和激活Caspase-3剪切体水平诱导HEL细胞凋亡。
文摘FMS-related tyrosine kinase 3(FLT3)mutations,present in about 25%-30%of acute myeloid leukemia(AML)patients,constitute one of the most frequently detected mutations in these patients.The binding of FLT3L to FLT3 activates the phosphatidylinositol 3-kinase(PI3K)and RAS pathways,producing increased cell proliferation and the inhibition of apoptosis.Two types of FLT3 mutations exist:FLT3-ITD and FLT3-TKD(point mutations in D835 and I836 or deletion of codon I836).A class of drugs,tyrosine-kinase inhibitors(TKI),targeting mutated FLT3,is already available with 1st and 2nd generation molecules,but only midostaurin and gilteritinib are currently approved.However,the emergence of resistance or the selection of clones not responding to FLT3 inhibitors has become an important clinical dilemma,as the duration of clinical responses is generally limited to a few months.This review analyzes the insights into mechanisms of resistance to TKI and poses a particular view on the clinical relevance of this phenomenon.Has resistance been overlooked?Indeed,FLT3 inhibitors have significantly contributed to reducing the negative impact of FLT3 mutations on the prognosis of AML patients who are no longer considered at high risk by the European LeukemiaNet(ELN)2022.Finally,several ongoing efforts to overcome resistance to FLT3-inhibitors will be presented:new generation FLT3 inhibitors in monotherapy or combined with standard chemotherapy,hypomethylating drugs,or IDH1/2 inhibitors,Bcl2 inhibitors;novel anti-human FLT3 monoclonal antibodies(e.g.,FLT3/CD3 bispecific antibodies);FLT3-CAR T-cells;CDK4/6 kinase inhibitor(e.g.,palbociclib).
基金supported by a grant from the National Cancer Institute,USA(No.R03CA252818 to NN).
文摘Introduction:Mastocytosis,a clonal proliferation of mast cells commonly involving the skin and bone marrow,has a varied clinical presentation ranging from cutaneous lesions to systemic disease.Cutaneous mastocytosis is managed symptomatically,but systemic mastocytosis is treated with targeted therapy against the mutated receptor tyrosine kinase c-KIT,the pathogenic driver of mastocytosis.However,there are no guidelines for the treatment of cutaneous mastocytosis refractory to symptomatic management.We herein report a method to select genetically informed therapy for symptomatic and recalcitrant cutaneous mastocytosis.Case presentation:We performed a mutational analysis of dermal mast cells after enrichment by laser capture in a 23-year-old woman with recalcitrant cutaneous mastocytosis.The analysis revealed a aspartic acid to valine substitution at codon 816(D816V)mutation in the protein c-KIT.Based on these results,we initiated treatment with the multi-kinase/KIT inhibitor midostaurin,a treatment effective against the D816V c-KIT mutation.After 3 months of treatment,the patient exhibited a reduction in the number and size of cutaneous lesions and reported resolution of pruritus and decreased severity of other mast cell-related symptoms.Discussion:The treatment of mastocytosis relies heavily on whether the disease is limited to the skin or systemic.However,there are no guidelines for cutaneous mastocytosis that does not respond to symptomatic management.In the present report describing a patient with recalcitrant cutaneous mastocytosis,we describe a strategy in which skin mutational analysis is used to guide the selection of targeted therapy.Conclusion:Performing mast cell mutational analyses in the skin provides a means to select targeted therapy for symptomatic and refractory cutaneous mastocytosis.
