5-Formylcytosine(5fC), as an important epigenetic modification, plays a vital role in diverse biological processes and multiple diseases by regulating gene expression. Owing to the extremely low abundance of 5fC in al...5-Formylcytosine(5fC), as an important epigenetic modification, plays a vital role in diverse biological processes and multiple diseases by regulating gene expression. Owing to the extremely low abundance of 5fC in all mammalian tissues and high structural similarity with other cytosine derivatives, the precise and sensitive detection of 5fC is challenging. Herein, a photo-elutable and template-free isothermal amplification strategy has been proposed for the sensitive detection of 5fC in genomic DNA based on5fC-specific biotinylation, enrichment, photocleavage, and terminal deoxynucleotidyl transferase(Td T)-assisted fluorescence signal amplification, which is termed 5fC-PTIAS. By introducing the highly specific chemolabeling and the one-step photoelution processes, this strategy possesses a minimal nonspecific background as well as a much higher amplification efficiency. With the high signal-to-noise ratio, this strategy can achieve the accurate quantification of 5fC in various biological samples including mouse brain, kidney, and liver, with a limit of detection(LOD) of 0.025‰ in DNA(S/N=3). These results not only confirm the widespread distribution of 5fC but also indicate its significant variation in different tissues and ages. The bisulfite-and mass spectrometry-free strategy is highly sensitive, selective, and easily mastered, holding great promise in detecting other epigenetic modifications with much lower levels.展开更多
目的探讨甲基转移酶5(methyltransferase-like 5,METTL5)在三阴乳腺癌(triple-negative breast cancer,TNBC)中的作用和潜在机制。方法采用免疫组织化学方法和Western blot检测TNBC肿瘤组织和细胞系中METTL5的表达情况。用靶向METTL5的s...目的探讨甲基转移酶5(methyltransferase-like 5,METTL5)在三阴乳腺癌(triple-negative breast cancer,TNBC)中的作用和潜在机制。方法采用免疫组织化学方法和Western blot检测TNBC肿瘤组织和细胞系中METTL5的表达情况。用靶向METTL5的shRNA(shRNA-METTL5)转染TNBC细胞后,用CCK-8、集落形成、伤口愈合以及Transwell实验分别检测细胞增殖活性、迁移与侵袭,Western blot检测Wnt/β-catenin信号关键蛋白的表达。构建异种移植瘤模型,验证敲降METTL5对TNBC细胞在体内生长以及Wnt/β-catenin信号活性的影响。结果METTL5在TNBC肿瘤组织和细胞系中表达上调(P<0.01)。敲降METTL5可抑制TNBC细胞的增殖、迁移和侵袭并降低了Wnt/β-catenin信号分子β-catenin、细胞周期蛋白(Cyclin)D1、基质金属蛋白酶(MMP)-2和MMP-7的表达(均P<0.01)。体内实验显示,敲降METTL5减缓了移植瘤生长和Wnt/β-catenin信号活性。结论敲降METTL5能抑制TNBC细胞的增殖、迁移与侵袭,其作用可能与抑制Wnt/β-catenin信号通路有关。展开更多
目的:研究溶质载体家族6成员9(solute carrier family 6 member 9,SLC6A9)表达对结直肠癌细胞增殖、迁移和5-氟尿嘧啶(5-fluorouracil,5-FU)药物敏感性的影响。方法:TCGA数据库分析、实时荧光定量PCR和Western blot分析检测SLC6A9在结...目的:研究溶质载体家族6成员9(solute carrier family 6 member 9,SLC6A9)表达对结直肠癌细胞增殖、迁移和5-氟尿嘧啶(5-fluorouracil,5-FU)药物敏感性的影响。方法:TCGA数据库分析、实时荧光定量PCR和Western blot分析检测SLC6A9在结肠癌组织、正常结肠细胞系(NCM460)和结直肠癌细胞系(SW620、HCT116、HT29、Lovo和SW480)中的表达。将SCL6A9过表达质粒及阴性对照(SLC6A9 OE、Vector)转染HT29细胞,将SCL6A9小干扰RNA及阴性对照(SLC6A9 siRNA1#、siRNA2#和Scramble)转染SW620细胞。划痕愈合实验和Transwell实验检测各组细胞的迁移、侵袭能力。Western blot和细胞免疫荧光检测EMT相关蛋白E-cadherin、Vimentin的表达水平。利用CCK-8法和构建裸鼠移植瘤模型检测SLC6A9过表达对结直肠癌细胞5-FU药物敏感性的影响。结果:与正常结肠组织和NCM460细胞相比,SLC6A9在结肠癌组织和结直肠癌细胞系中低表达(均P<0.05)。SLC6A9过表达引起E-cadherin蛋白表达增加,Vimentin蛋白水平降低,抑制结直肠癌细胞的迁移、侵袭(P<0.05)。SLC6A9低表达引起E-cadherin蛋白表达降低,Vimentin蛋白水平增加,促进结直肠癌细胞的迁移、侵袭能力(P<0.05)。SLC6A9过表达提高了5-FU的药物敏感性,并使肿瘤生长缓慢,质量减轻(P<0.05)。而SLC6A9低表达降低了5-FU的药物敏感性(P<0.05)。结论:SLC6A9过表达能够抑制结直肠癌细胞的迁移、侵袭和EMT进程,并增强5-FU对结直肠癌细胞的药物敏感性。展开更多
食品加工过程中的美拉德反应有助于形成一些热诱导毒性产物,包括晚期糖基化终末产物(advanced glycation end products,AGEs)和5-羟甲基糠醛(5-hydroxymethylfurfural,5-HMF)。食源性AGEs在体内的积累和循环与糖尿病并发症的发生有关,...食品加工过程中的美拉德反应有助于形成一些热诱导毒性产物,包括晚期糖基化终末产物(advanced glycation end products,AGEs)和5-羟甲基糠醛(5-hydroxymethylfurfural,5-HMF)。食源性AGEs在体内的积累和循环与糖尿病并发症的发生有关,同时可能诱发氧化应激、炎症和动脉粥样硬化。5-HMF的代谢物5-磺基氧甲基糠醛(5-sulfooxymethylfurfural,5-SMF)有潜在基因毒性和致癌性。如何控制热加工食品中这些危害物的形成已成为食品行业的关注焦点。本文从美拉德反应和焦糖化反应两条途径探究了AGEs和5-HMF的形成机理,并对近5年二者的检测方法进行了综述,阐述了各类方法的优缺点,以期为建立二者的通用检测方法奠定基础。在此基础上,从削减前体物质的供给、阻断中间体的转化,以及去除已经生成的AGEs和5-HMF这3个方面着手,综述了近年来相应所采用的抑制策略,以期为AGEs和5-HMF在食品中的控制及热加工食品质量与安全管理提供理论依据。展开更多
基金supported by the Scientific Technology Project of Shenzhen City(Nos.JCYJ20200109142410170 and JCYJ20210324124003008)the National Natural Science Foundation of China(No.21974153)+2 种基金the Scientific Technology Project of Guangzhou City(No.202103000003)the Guangdong Natural Science Foundation(No.2019A1515010587)the Guangdong Science and Technology Plan Project(No.2020B1212060077)。
文摘5-Formylcytosine(5fC), as an important epigenetic modification, plays a vital role in diverse biological processes and multiple diseases by regulating gene expression. Owing to the extremely low abundance of 5fC in all mammalian tissues and high structural similarity with other cytosine derivatives, the precise and sensitive detection of 5fC is challenging. Herein, a photo-elutable and template-free isothermal amplification strategy has been proposed for the sensitive detection of 5fC in genomic DNA based on5fC-specific biotinylation, enrichment, photocleavage, and terminal deoxynucleotidyl transferase(Td T)-assisted fluorescence signal amplification, which is termed 5fC-PTIAS. By introducing the highly specific chemolabeling and the one-step photoelution processes, this strategy possesses a minimal nonspecific background as well as a much higher amplification efficiency. With the high signal-to-noise ratio, this strategy can achieve the accurate quantification of 5fC in various biological samples including mouse brain, kidney, and liver, with a limit of detection(LOD) of 0.025‰ in DNA(S/N=3). These results not only confirm the widespread distribution of 5fC but also indicate its significant variation in different tissues and ages. The bisulfite-and mass spectrometry-free strategy is highly sensitive, selective, and easily mastered, holding great promise in detecting other epigenetic modifications with much lower levels.
文摘目的:研究溶质载体家族6成员9(solute carrier family 6 member 9,SLC6A9)表达对结直肠癌细胞增殖、迁移和5-氟尿嘧啶(5-fluorouracil,5-FU)药物敏感性的影响。方法:TCGA数据库分析、实时荧光定量PCR和Western blot分析检测SLC6A9在结肠癌组织、正常结肠细胞系(NCM460)和结直肠癌细胞系(SW620、HCT116、HT29、Lovo和SW480)中的表达。将SCL6A9过表达质粒及阴性对照(SLC6A9 OE、Vector)转染HT29细胞,将SCL6A9小干扰RNA及阴性对照(SLC6A9 siRNA1#、siRNA2#和Scramble)转染SW620细胞。划痕愈合实验和Transwell实验检测各组细胞的迁移、侵袭能力。Western blot和细胞免疫荧光检测EMT相关蛋白E-cadherin、Vimentin的表达水平。利用CCK-8法和构建裸鼠移植瘤模型检测SLC6A9过表达对结直肠癌细胞5-FU药物敏感性的影响。结果:与正常结肠组织和NCM460细胞相比,SLC6A9在结肠癌组织和结直肠癌细胞系中低表达(均P<0.05)。SLC6A9过表达引起E-cadherin蛋白表达增加,Vimentin蛋白水平降低,抑制结直肠癌细胞的迁移、侵袭(P<0.05)。SLC6A9低表达引起E-cadherin蛋白表达降低,Vimentin蛋白水平增加,促进结直肠癌细胞的迁移、侵袭能力(P<0.05)。SLC6A9过表达提高了5-FU的药物敏感性,并使肿瘤生长缓慢,质量减轻(P<0.05)。而SLC6A9低表达降低了5-FU的药物敏感性(P<0.05)。结论:SLC6A9过表达能够抑制结直肠癌细胞的迁移、侵袭和EMT进程,并增强5-FU对结直肠癌细胞的药物敏感性。
文摘食品加工过程中的美拉德反应有助于形成一些热诱导毒性产物,包括晚期糖基化终末产物(advanced glycation end products,AGEs)和5-羟甲基糠醛(5-hydroxymethylfurfural,5-HMF)。食源性AGEs在体内的积累和循环与糖尿病并发症的发生有关,同时可能诱发氧化应激、炎症和动脉粥样硬化。5-HMF的代谢物5-磺基氧甲基糠醛(5-sulfooxymethylfurfural,5-SMF)有潜在基因毒性和致癌性。如何控制热加工食品中这些危害物的形成已成为食品行业的关注焦点。本文从美拉德反应和焦糖化反应两条途径探究了AGEs和5-HMF的形成机理,并对近5年二者的检测方法进行了综述,阐述了各类方法的优缺点,以期为建立二者的通用检测方法奠定基础。在此基础上,从削减前体物质的供给、阻断中间体的转化,以及去除已经生成的AGEs和5-HMF这3个方面着手,综述了近年来相应所采用的抑制策略,以期为AGEs和5-HMF在食品中的控制及热加工食品质量与安全管理提供理论依据。
基金Key Research and Development Plan of Shaanxi Province(2023-YBGY-290)Research Project of Shaanxi Yanchang Petroleum(Group)Co.,Ltd.(No.ycsy2023ky-B-81)。