Objective: The aim of this study was to investigate the underlying mechanism whereby HBx modulates the targeting of NUSAP1 by miR-18b to enhance hepatocarcinogenesis.Methods: We employed an integrated approach of bioi...Objective: The aim of this study was to investigate the underlying mechanism whereby HBx modulates the targeting of NUSAP1 by miR-18b to enhance hepatocarcinogenesis.Methods: We employed an integrated approach of bioinformatics analysis and molecular experiments in hepatoma cells, HBV transgenic mice, and clinical liver cancer tissues to investigate the role of HBx-regulated miR-18b in the development of liver cancer.Results: In this study, we report that the HBx-mediated tumor suppressor miR-18b modulates hepatocarcinogenesis during the host-HBV interaction. The expression levels of miR-18b were lower in clinical HBV-positive liver cancer tissues and liver tissues of HBV-transgenic mice. Interestingly, HBx inhibited miR-18b expression by inducing the methylation of CpG islands in its promoter. Accordingly, we tested the hypothesis that HBx enhanced hepatocarcinogenesis by increasing the expression of target genes of miR-18b. Moreover, we identified nucleolar spindle-associated protein 1(NUSAP1) as one of the target genes of miR-18b.NUSAP1 was expressed at high levels in liver cancer tissues. Interestingly, HBx up-regulated NUSAP1 by suppressing miR-18b.Functionally, miR-18b significantly inhibited the proliferation of hepatoma cells by depressing NUSAP1 levels in vivo and in vitro.Conclusions: Thus, we conclude that the targeting of NUSAP1 mRNA by the tumor suppressor miR-18b is controlled by HBxmodulated promoter methylation during the host-virus interaction, leading to hepatocarcinogenesis. Our findings provide new insights into the mechanism by which HBx-mediated miRNAs modulate hepatocarcinogenesis.展开更多
Microtubules play important roles in mitotic spindle assembly and chromosome segregation to maintain normal cell cycle progression.A number of microtubule-associated proteins have been identified in epithelial and neu...Microtubules play important roles in mitotic spindle assembly and chromosome segregation to maintain normal cell cycle progression.A number of microtubule-associated proteins have been identified in epithelial and neural cell cultures;however,their physiological significance is not well characterized due to the lack of appropriate in vivo animal models.Nucleolar spindleassociated protein(NuSAP)is a microtubule-binding protein and is reported to be involved in mitosis by cell culture studies.In this report,we identified the zebrafish homologue of human NuSAP and investigated its expression profile and functions.Using in situ hybridization,we demonstrated that transcripts of zebrafish nusap1 are specifically expressed in the retina,forebrain,hindbrain and neural crest.When the in vivo expression of nusap1 was knocked down through antisense oligonucleotide morpholino technology,the morphants of nusap1 showed impaired morphogenesis in the trunk and yolk extension,implying the involvement of Nusap1 in cell migration.Mechanistic studies revealed that nusap1 morphants have an altered expression pattern of neural crest markers crestin and sox9b,but normal expression of blood vessel and notochord markers gata1 and shh.In addition,nusap1 mRNA injection caused serious apoptosis in retina and hindbrain tissue,and these phenotypes can be rescued by co-injection of morpholino against nusap1.These observations not only suggest a role for Nusap1 in connecting apoptosis with cell migration,but also provide strong evidences that Nusap1 is potentially involved in morphogenesis in vertebrates.展开更多
核仁纺锤体相关蛋白1(nucleolar and spindle-associated protein 1, NUSAP1)是一种微管结合蛋白,它与微管结合后稳定微管并参与细胞分裂,与染色体结合后,促进有丝分裂纺锤体微管的形成;因此NUSAP1与细胞有丝分裂进程、纺锤体的形成有...核仁纺锤体相关蛋白1(nucleolar and spindle-associated protein 1, NUSAP1)是一种微管结合蛋白,它与微管结合后稳定微管并参与细胞分裂,与染色体结合后,促进有丝分裂纺锤体微管的形成;因此NUSAP1与细胞有丝分裂进程、纺锤体的形成有密切关系。NUSAP1的一个关键功能是在有丝分裂早期和晚期起调节作用。NUSAP1在许多恶性肿瘤中高表达,因此通过NUSAP1的靶向作用机制的研究筛选出合适的靶向药物对于恶性肿瘤的治疗具有潜在的应用前景。本文就NUSAP1在恶性肿瘤中的作用机制及其在恶性肿瘤治疗中的价值进行分析与总结。展开更多
目的探讨核仁纺锤体相关蛋白1(nucleolar spindle-associated protein 1,NuSAP1)在宫颈癌组织中的表达与临床病理特征的关系及其临床意义。方法采用Envision二步法免疫组织化学染色检测NuSAP1蛋白在宫颈癌及正常宫颈组织中的表达情况,...目的探讨核仁纺锤体相关蛋白1(nucleolar spindle-associated protein 1,NuSAP1)在宫颈癌组织中的表达与临床病理特征的关系及其临床意义。方法采用Envision二步法免疫组织化学染色检测NuSAP1蛋白在宫颈癌及正常宫颈组织中的表达情况,应用基因公共数据库在线分析NuSAP1 mRNA在宫颈癌和正常宫颈组织中的表达水平。结果NuSAP1蛋白在宫颈癌组织中的高表达率为54.1%(60/111),正常宫颈组织中的高表达率为5.0%(2/40);NuSAP1 mRNA在宫颈癌组织中表达水平高于正常宫颈组织。宫颈癌中NuSAP1蛋白的表达水平与组织分化程度、淋巴结转移、淋巴脉管间隙浸润、间质浸润深度、FIGO分期相关,与患者年龄、肿瘤大小、组织学类型、宫旁浸润无关。NuSAPl蛋白高表达患者的术后复发、转移率高于低表达患者。结论NuSAP1在宫颈癌组织中存在高表达,其表达水平对宫颈癌患者术后复发、转移的预测具有指导意义。展开更多
基金supported in part by grants from National Basic Research Program of China (973 Program, Grant No. 2015CB553703)National Natural Science Foundation of China (Grant No. 31670769 and 31470756)
文摘Objective: The aim of this study was to investigate the underlying mechanism whereby HBx modulates the targeting of NUSAP1 by miR-18b to enhance hepatocarcinogenesis.Methods: We employed an integrated approach of bioinformatics analysis and molecular experiments in hepatoma cells, HBV transgenic mice, and clinical liver cancer tissues to investigate the role of HBx-regulated miR-18b in the development of liver cancer.Results: In this study, we report that the HBx-mediated tumor suppressor miR-18b modulates hepatocarcinogenesis during the host-HBV interaction. The expression levels of miR-18b were lower in clinical HBV-positive liver cancer tissues and liver tissues of HBV-transgenic mice. Interestingly, HBx inhibited miR-18b expression by inducing the methylation of CpG islands in its promoter. Accordingly, we tested the hypothesis that HBx enhanced hepatocarcinogenesis by increasing the expression of target genes of miR-18b. Moreover, we identified nucleolar spindle-associated protein 1(NUSAP1) as one of the target genes of miR-18b.NUSAP1 was expressed at high levels in liver cancer tissues. Interestingly, HBx up-regulated NUSAP1 by suppressing miR-18b.Functionally, miR-18b significantly inhibited the proliferation of hepatoma cells by depressing NUSAP1 levels in vivo and in vitro.Conclusions: Thus, we conclude that the targeting of NUSAP1 mRNA by the tumor suppressor miR-18b is controlled by HBxmodulated promoter methylation during the host-virus interaction, leading to hepatocarcinogenesis. Our findings provide new insights into the mechanism by which HBx-mediated miRNAs modulate hepatocarcinogenesis.
基金grant from National Nature Science Foundation of China(Grant No.30900748)Natural Science Foundation in Fujian province(Grant No.2009J01194)H.H.and Chinese National Basic Research Programs(Grant No.2006CB910802)to H.F.
文摘Microtubules play important roles in mitotic spindle assembly and chromosome segregation to maintain normal cell cycle progression.A number of microtubule-associated proteins have been identified in epithelial and neural cell cultures;however,their physiological significance is not well characterized due to the lack of appropriate in vivo animal models.Nucleolar spindleassociated protein(NuSAP)is a microtubule-binding protein and is reported to be involved in mitosis by cell culture studies.In this report,we identified the zebrafish homologue of human NuSAP and investigated its expression profile and functions.Using in situ hybridization,we demonstrated that transcripts of zebrafish nusap1 are specifically expressed in the retina,forebrain,hindbrain and neural crest.When the in vivo expression of nusap1 was knocked down through antisense oligonucleotide morpholino technology,the morphants of nusap1 showed impaired morphogenesis in the trunk and yolk extension,implying the involvement of Nusap1 in cell migration.Mechanistic studies revealed that nusap1 morphants have an altered expression pattern of neural crest markers crestin and sox9b,but normal expression of blood vessel and notochord markers gata1 and shh.In addition,nusap1 mRNA injection caused serious apoptosis in retina and hindbrain tissue,and these phenotypes can be rescued by co-injection of morpholino against nusap1.These observations not only suggest a role for Nusap1 in connecting apoptosis with cell migration,but also provide strong evidences that Nusap1 is potentially involved in morphogenesis in vertebrates.
文摘核仁纺锤体相关蛋白1(nucleolar and spindle-associated protein 1, NUSAP1)是一种微管结合蛋白,它与微管结合后稳定微管并参与细胞分裂,与染色体结合后,促进有丝分裂纺锤体微管的形成;因此NUSAP1与细胞有丝分裂进程、纺锤体的形成有密切关系。NUSAP1的一个关键功能是在有丝分裂早期和晚期起调节作用。NUSAP1在许多恶性肿瘤中高表达,因此通过NUSAP1的靶向作用机制的研究筛选出合适的靶向药物对于恶性肿瘤的治疗具有潜在的应用前景。本文就NUSAP1在恶性肿瘤中的作用机制及其在恶性肿瘤治疗中的价值进行分析与总结。
