BACKGROUND Ataxia-telangiectasia(AT)is a rare,autosomal recessive,multisystem disorder.Because most clinicians have low awareness of the disease,only scarce reports of AT exist in the literature,especially of cases wi...BACKGROUND Ataxia-telangiectasia(AT)is a rare,autosomal recessive,multisystem disorder.Because most clinicians have low awareness of the disease,only scarce reports of AT exist in the literature,especially of cases with lymphoma/leukemia.CASE SUMMARY A 7-year-old girl with a history of recurrent respiratory tract infections was referred to our department because of unstable walking for 5 years and enlarged neck nodes for 2-mo duration.Physical examination revealed scleral telangiectasia and cerebellar ataxia.Elevated alpha-fetoprotein,decreased serum immunoglobulin,and decreased T cell function were the major findings of laboratory examination.Histological analysis of cervical lymph node biopsy was suggestive of classical Hodgkin's lymphoma.Genetic examination showed heterozygous nucleotide variation of c.6679C>T and heterozygous nucleotide variation of c.5773 delG in the ATM gene;her parents were heterozygotes.The final diagnosis was AT with Hodgkin's lymphoma.CONCLUSION Clinicians should strengthen their understanding of AT diseases.Gene diagnosis plays an important role in its diagnosis and treatment.展开更多
Objective:Mitotic arrest-deficient protein 1(MAD1)is a kinetochore protein essential for the mitotic spindle checkpoint.Proteomic studies have indicated that MAD1 is a component of the DNA damage response(DDR)pathway....Objective:Mitotic arrest-deficient protein 1(MAD1)is a kinetochore protein essential for the mitotic spindle checkpoint.Proteomic studies have indicated that MAD1 is a component of the DNA damage response(DDR)pathway.However,whether and how MAD1 might be directly involved in the DDR is largely unknown.Methods:We ectopically expressed the wild type,or a phosphorylation-site--mutated form of MAD1 in MAD1 knockdown cells to look for complementation effects.We used the comet assay,colony formation assay,immunofluorescence staining,and flow cytometry to assess the DDR,radiosensitivity,and the G2/M checkpoint.We employed co-immunoprecipitation followed by mass spectrometry to identify MAD1 interacting proteins.Data were analyzed using the unpaired Student'st-test.Results:We showed that MAD1 was required for an optimal DDR,as knocking down MAD1 resulted in impaired DNA repair and hypersensitivity to ionizing radiation(IR).We found that IR-induced serine 214 phosphorylation was ataxia-telangiectasia mutated(ATM)kinase-dependent.Mutation of serine 214 to alanine failed to rescue the phenotypes of MAD1 knockdown cells in response to IR.Using mass spectrometry,we identified a protein complex mediated by MAD1 serine 214 phosphorylation in response to IR.Among them,we showed that KU80 was a key protein that displayed enhanced interaction with MAD1 after DNA damage.Finally,we showed that MAD1 interaction with KU80 required serine 214 phosphorylation,and it was essential for activation of DNA protein kinases catalytic subunit(DNA-PKcs).Conclusions:MAD1 serine 214 phosphorylation mediated by ATM kinase in response to IR was required for the interaction with KU80 and activation of DNA-PKCs.展开更多
Objective Vasculogenic mimicry(VM)is a novel vasculogenic process integral to glioma stem cells(GSCs)in glioblastoma(GBM).However,the relationship between VM and ataxia-telangiectasia mutated(ATM)serine/threonine kina...Objective Vasculogenic mimicry(VM)is a novel vasculogenic process integral to glioma stem cells(GSCs)in glioblastoma(GBM).However,the relationship between VM and ataxia-telangiectasia mutated(ATM)serine/threonine kinase activation,which confers chemoradiotherapy resistance,remains unclear.Methods We investigated VM formation and phosphorylated ATM(pATM)levels by CD31/GFAPperiodic acid-Schiff dual staining and immunohistochemical staining in 145 GBM specimens.Glioma stem-like cells(GSLCs)derived from the formatted spheres of U87 and U251 cell lines and their pATM level and VM formation ability were examined using western blot and three-dimensional culture.For the examination of the function of pATM in VM formation by GSLCs,ATM knockdown by shRNAs and deactivated via ATM phosphorylation inhibitor KU55933 were studied.Results VM and high pATM expression occurred in 38.5% and 41.8% of tumors,respectively,and were significantly associated with reduced progression-free and overall survival.Patients with VM-positive GBMs exhibited higher pATM levels(r_(s)=0.425,P=0.01).The multivariate analysis established VM as an independent negative prognostic factor(P=0.002).Furthermore,GSLCs expressed high levels of pATM and formed vascular-like networks in vitro.ATM inactivation or knockdown hindered VM-like network formation concomitant with the downregulation of pVEGFR-2,VE-cadherin,and laminin B2.Conclusion VM may predict a poor GBM prognosis and is associated with pATM expression.We propose that pATM promotes VM through extracellular matrix modulation and VE-Cadherin/pVEGFR-2 activation,thereby highlighting ATM activation as a potential target for enhancing anti-angiogenesis therapies for GBM.展开更多
从分子库中筛选出潜在活性化合物,是药物发现常用的方法。然而,随着化学空间的不断探索,目前已有超过数十亿分子的化合物库,仅仅依靠分子对接已不足以从超大化合物库中对特定靶点抑制剂进行快速筛选。本研究提出了一种筛选潜在活性化合...从分子库中筛选出潜在活性化合物,是药物发现常用的方法。然而,随着化学空间的不断探索,目前已有超过数十亿分子的化合物库,仅仅依靠分子对接已不足以从超大化合物库中对特定靶点抑制剂进行快速筛选。本研究提出了一种筛选潜在活性化合物的方法,通过计算物理化学性质相似性、构建机器学习预测模型以及分子对接等步骤,对含有55亿分子的候选化合物库进行过滤筛选,最终得到51个具有共济失调毛细血管扩张突变基因和Rad3相关蛋白(ataxia telangiectasia-mutated and Rad3-related,ATR)激酶潜在抑制活性的化合物。该方法为从超大库中快速筛选新颖潜在活性分子提供了有效途径。展开更多
DNA损伤应答(DNAdamageresponse,DDR)机制包括检测DNA损伤,阻滞细胞周期和启动DNA修复。共济失调毛细血管扩张和Rad3相关激酶(ataxia telangiectasia and Rad3-related,ATR)是DDR核心的关键激酶,负责感知复制应激(replica-tion stress,...DNA损伤应答(DNAdamageresponse,DDR)机制包括检测DNA损伤,阻滞细胞周期和启动DNA修复。共济失调毛细血管扩张和Rad3相关激酶(ataxia telangiectasia and Rad3-related,ATR)是DDR核心的关键激酶,负责感知复制应激(replica-tion stress,RS)并将其信号传导至S和G2/M检查点以启动DNA修复。在肿瘤细胞中G1检查点缺失和癌基因的激活,导致癌症细胞更多进入RS增加的S期。因此,肿瘤细胞更加依赖S和G2/M检查点,使其成为一个有吸引力的靶点。ATR抑制剂是目前抗肿瘤药物开发的热点,部分ATR抑制剂目前已经进入临床试验阶段。本综述旨在总结支持ATR抑制剂作为单药以及与化疗、放疗和新型靶向药物(如PARP抑制剂)联合使用的临床试验数据,并讨论目前ATR抑制剂开发和生物标志物探索中面临的挑战。展开更多
文摘BACKGROUND Ataxia-telangiectasia(AT)is a rare,autosomal recessive,multisystem disorder.Because most clinicians have low awareness of the disease,only scarce reports of AT exist in the literature,especially of cases with lymphoma/leukemia.CASE SUMMARY A 7-year-old girl with a history of recurrent respiratory tract infections was referred to our department because of unstable walking for 5 years and enlarged neck nodes for 2-mo duration.Physical examination revealed scleral telangiectasia and cerebellar ataxia.Elevated alpha-fetoprotein,decreased serum immunoglobulin,and decreased T cell function were the major findings of laboratory examination.Histological analysis of cervical lymph node biopsy was suggestive of classical Hodgkin's lymphoma.Genetic examination showed heterozygous nucleotide variation of c.6679C>T and heterozygous nucleotide variation of c.5773 delG in the ATM gene;her parents were heterozygotes.The final diagnosis was AT with Hodgkin's lymphoma.CONCLUSION Clinicians should strengthen their understanding of AT diseases.Gene diagnosis plays an important role in its diagnosis and treatment.
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.81672743 and 81974464)Beijing Tianjin Hebei Basic Research Cooperation Project(Grant No.19JCZDJC64500(Z))+4 种基金Shenzhen Basic Research Project(Grant No.JCYJ20160331114230843)Tianjin Municipal Health Commission(Grant Nos.2015KR11 and 2013KG134)Tianjin Municipal Science and Technology Bureau(Grant No.18JCYBJC27800)US NIH grant RO 1 CAI33093,the Alabama Innovation Fund of the United Statesthe Tianjin Medical University Cancer Institute and Hospital Innovation Fund(Grant No.1803)。
文摘Objective:Mitotic arrest-deficient protein 1(MAD1)is a kinetochore protein essential for the mitotic spindle checkpoint.Proteomic studies have indicated that MAD1 is a component of the DNA damage response(DDR)pathway.However,whether and how MAD1 might be directly involved in the DDR is largely unknown.Methods:We ectopically expressed the wild type,or a phosphorylation-site--mutated form of MAD1 in MAD1 knockdown cells to look for complementation effects.We used the comet assay,colony formation assay,immunofluorescence staining,and flow cytometry to assess the DDR,radiosensitivity,and the G2/M checkpoint.We employed co-immunoprecipitation followed by mass spectrometry to identify MAD1 interacting proteins.Data were analyzed using the unpaired Student'st-test.Results:We showed that MAD1 was required for an optimal DDR,as knocking down MAD1 resulted in impaired DNA repair and hypersensitivity to ionizing radiation(IR).We found that IR-induced serine 214 phosphorylation was ataxia-telangiectasia mutated(ATM)kinase-dependent.Mutation of serine 214 to alanine failed to rescue the phenotypes of MAD1 knockdown cells in response to IR.Using mass spectrometry,we identified a protein complex mediated by MAD1 serine 214 phosphorylation in response to IR.Among them,we showed that KU80 was a key protein that displayed enhanced interaction with MAD1 after DNA damage.Finally,we showed that MAD1 interaction with KU80 required serine 214 phosphorylation,and it was essential for activation of DNA protein kinases catalytic subunit(DNA-PKcs).Conclusions:MAD1 serine 214 phosphorylation mediated by ATM kinase in response to IR was required for the interaction with KU80 and activation of DNA-PKCs.
基金supported by the Natural Science Foundation of Anhui Province(2208085MH250,2308085MH272)National Key Research and Development Program of China(2021YFF1201000)+2 种基金Natural Science Research Project of the Anhui Educational Committee(2023AH040404,2023AH053402)Anhui Provincial Health and Medical Research Project(AHWJ2023A10143)Research Funds of Centre for Leading Medicine and Advanced Technologies of IHM(2023IHM01043)。
文摘Objective Vasculogenic mimicry(VM)is a novel vasculogenic process integral to glioma stem cells(GSCs)in glioblastoma(GBM).However,the relationship between VM and ataxia-telangiectasia mutated(ATM)serine/threonine kinase activation,which confers chemoradiotherapy resistance,remains unclear.Methods We investigated VM formation and phosphorylated ATM(pATM)levels by CD31/GFAPperiodic acid-Schiff dual staining and immunohistochemical staining in 145 GBM specimens.Glioma stem-like cells(GSLCs)derived from the formatted spheres of U87 and U251 cell lines and their pATM level and VM formation ability were examined using western blot and three-dimensional culture.For the examination of the function of pATM in VM formation by GSLCs,ATM knockdown by shRNAs and deactivated via ATM phosphorylation inhibitor KU55933 were studied.Results VM and high pATM expression occurred in 38.5% and 41.8% of tumors,respectively,and were significantly associated with reduced progression-free and overall survival.Patients with VM-positive GBMs exhibited higher pATM levels(r_(s)=0.425,P=0.01).The multivariate analysis established VM as an independent negative prognostic factor(P=0.002).Furthermore,GSLCs expressed high levels of pATM and formed vascular-like networks in vitro.ATM inactivation or knockdown hindered VM-like network formation concomitant with the downregulation of pVEGFR-2,VE-cadherin,and laminin B2.Conclusion VM may predict a poor GBM prognosis and is associated with pATM expression.We propose that pATM promotes VM through extracellular matrix modulation and VE-Cadherin/pVEGFR-2 activation,thereby highlighting ATM activation as a potential target for enhancing anti-angiogenesis therapies for GBM.
文摘从分子库中筛选出潜在活性化合物,是药物发现常用的方法。然而,随着化学空间的不断探索,目前已有超过数十亿分子的化合物库,仅仅依靠分子对接已不足以从超大化合物库中对特定靶点抑制剂进行快速筛选。本研究提出了一种筛选潜在活性化合物的方法,通过计算物理化学性质相似性、构建机器学习预测模型以及分子对接等步骤,对含有55亿分子的候选化合物库进行过滤筛选,最终得到51个具有共济失调毛细血管扩张突变基因和Rad3相关蛋白(ataxia telangiectasia-mutated and Rad3-related,ATR)激酶潜在抑制活性的化合物。该方法为从超大库中快速筛选新颖潜在活性分子提供了有效途径。
文摘DNA损伤应答(DNAdamageresponse,DDR)机制包括检测DNA损伤,阻滞细胞周期和启动DNA修复。共济失调毛细血管扩张和Rad3相关激酶(ataxia telangiectasia and Rad3-related,ATR)是DDR核心的关键激酶,负责感知复制应激(replica-tion stress,RS)并将其信号传导至S和G2/M检查点以启动DNA修复。在肿瘤细胞中G1检查点缺失和癌基因的激活,导致癌症细胞更多进入RS增加的S期。因此,肿瘤细胞更加依赖S和G2/M检查点,使其成为一个有吸引力的靶点。ATR抑制剂是目前抗肿瘤药物开发的热点,部分ATR抑制剂目前已经进入临床试验阶段。本综述旨在总结支持ATR抑制剂作为单药以及与化疗、放疗和新型靶向药物(如PARP抑制剂)联合使用的临床试验数据,并讨论目前ATR抑制剂开发和生物标志物探索中面临的挑战。
