Apoptin在肿瘤治疗和肿瘤发生机制研究中的应用
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摘要
Apoptin是由鸡贫血病毒CAV(Chicken Anemia Virus)编码的小分子病毒蛋白,又称VP3。研究发现,Apoptin能够诱导多种不同组织来源的人肿瘤细胞凋亡;而在人正常二倍体细胞或原代细胞中,如造血干细胞CD34+、间叶干细胞及原代肝细胞等,Apoptin处于未活化状态,也不诱导细胞凋亡。长期表达Apoptin的人正常细胞并没有转化趋势或细胞毒性,进行正常分裂增殖;Apoptin转基因小鼠的正常生长发育等都证实了Apoptin对体内正常细胞的无毒性。Apoptin特异性诱导人肿瘤细胞凋亡,而对正常细胞无杀伤作用,是一种很有应用前景的抗肿瘤制剂。不仅如此,Apoptin还能被细胞的瞬时转化状态所激活。以SV40大T抗原(Simian Virus 40 Large Tumor antigen, LT)所建立的瞬时转化为细胞模型,用Apoptin作为细胞转化或肿瘤发生的特异性感应蛋白,对于肿瘤发生机制的研究具有重要意义。本文将从Apoptin在肿瘤基因治疗中的应用以及Apoptin在肿瘤发生机制研究中的应用两个方面进行探讨。
肝癌是世界上最常见也是最严重的恶性肿瘤之一。为了更好的将Apoptin用于肝癌的基因治疗,需要建立一种靶向性基因转导工具,特异性将Apoptin基因转移到肝细胞/肝癌细胞内。脱唾液酸糖蛋白受体(Asialoglycoprotein receptor, ASGPR)特异性地表达在肝细胞膜表面。体外和体内实验证明,通过多聚左旋赖氨酸(poly-L-lysine,PLL)与ASGPR的配体脱唾液酸糖蛋白(Asialoglycoprotein, Asor)相连接的DNA质粒,能够选择性被肝细胞所摄取。在本研究中,我们构建了由Asor,PLL和Apoptin表达质粒pcDNA-vp3组成的Asor-Apoptin肝细胞靶向性转导载体。体内实验证明,通过Asor-Apoptin转导系统,Apoptin基因可以被特异性地转移到肝细胞和原位肝癌细胞内,诱导肝肿瘤细胞凋亡,使肝脏肿瘤显著消退,并且对正常肝细胞无明显副作用,是一种有效的、很有应用前景的肝脏肿瘤治疗手段。这一研究成果对于Apoptin的临床应用具有重要意义。
另一方面,作为肿瘤特异性的细胞凋亡素,Apoptin同样在肿瘤相关信号通路的研究中具有重要的作用。体内和体外研究发现,在人肿瘤细胞及转化细胞内Apoptin108位苏氨酸被特异性磷酸化,Apoptin迅速移位到细胞核并诱导肿瘤细胞凋亡;而在人正常细胞内Apoptin则处于未磷酸化状态,停留在细胞质,也不诱导细胞凋亡。因此认为,在肿瘤及转化细胞内,普遍存在着一种与肿瘤相关的磷酸激酶,将Apoptin特异性磷酸化激活。
不仅如此,Apoptin还能被SV40大T抗原(LT)所建立的细胞瞬时转化状态所激活。以SV40早期基因产物(大T抗原和小T抗原)所建立的瞬时转化作为细胞模型,以Apoptin作为细胞转化或肿瘤发生的特异性感应蛋白,可以应用于肿瘤相关的信号通路的研究。前期研究表明,截短的N端SV40 T抗原(LT136/st,N端大T抗原LT136和全长小T抗原st)就能够替代全长大T抗原LT以激活Apoptin。我们进一步观察了N端T抗原的相关功能域在Apoptin激活效应中所起的作用。结果显示:SV40小T抗原(st) C端的PP2A结合功能域对Apoptin感应的肿瘤相关通路,起关键作用。有趣的是,本身不具有核定位作用的st(具有PP2A结合功能域)需要定位到细胞核才能激活Apoptin。
另外,共存于LT136和st的N端J功能域在结构上是必需的。LT136和st在其N端都具有完全相同的Hsc70结合功能域(即J功能域,1-82氨基酸)。据报道,Hsc70(热休克蛋白类似物)分子通过其C端的多肽结合功能域发生自结合,在细胞内以二聚体或多聚体的形式稳定存在。因此,我们推测,分别与LT136的J domain和st的J domain相结合两个相同的Hsc70分子有可能发生自结合,形成包括两个Hsc70分子、LT136和st的复合体。依靠LT136本身的NLS、或者与LT136所结合的pRb的NLS的核定位作用,这个包含st的复合体被定位到细胞核。在核基质中,st与PP2A相结合并抑制PP2A的生物活性,从而改变或者激活Apoptin所感应的肿瘤相关信号通路,Apoptin的肿瘤特异性磷酸激酶被激活,进而将Apoptin特异性磷酸化激活。研究结果表明,SV40小T抗原(st)被定位到细胞核,与PP2A结合并抑制PP2A的生物活性,诱导Apoptin感应的肿瘤相关信号通路的激活。该信号通路可能在肿瘤发生的早期阶段激发,并持续作用于肿瘤发生过程。PP2A可能是细胞转化乃至肿瘤发生较早期阶段的关键分子靶点,在肿瘤发生的较早期阶段发挥重要作用。
总之,本研究对Apoptin在肿瘤基因治疗和肿瘤发生机制研究中的应用两个方面进行了初步探讨。我们建立了一种肝细胞靶向性的Apoptin基因转导载体Asor-Apoptin,并且对其体内、体外的肝细胞靶向性和抑癌效应以及对正常组织细胞的毒副作用进行了观察。这一实验成果为进一步的临床应用奠定了基础。在肿瘤发生机制的研究中,我们用Apoptin作为肿瘤特异性的感应蛋白,对肿瘤相关的信号通路进行了初步探讨,进而提出细胞转化和肿瘤发生较早期阶段的关键分子靶点,为肿瘤发生机理的研究提供了有价值的实验依据。以上研究在国际上均未见报道,属于创新性研究探讨,它将为Apoptin的进一步深入研究提供实验及理论依据。
Apoptin, which is also named as VP3, is a small viral protein encoded by chicken anemia virus (CAV). The early study on Apoptin has shown that Apoptin induces apoptosis in a great variety of tumors (>70), as well as transformed cells. However, Apoptin does not induce significant apoptosis in human normal cells, including primary human hematopoietic stem CD34+ cells, primary human mesenchymal stem cells, or human primary hepatocytes. Human normal cells expressing Apoptin proliferate and divide regularly without any potential of transformation or toxicity. The normal development and growth of transgenic mice also prove that Apoptin is non-toxic to normal cells in vivo. Thus, Apoptin is a promising anti-tumor agent, which induces apoptosis in tumor or transformed cells but not in normal cells. Moreover, Apoptin can also be activated by the transient transforming signals conferred by SV40 LT (large tumor antigen). Under the transient transformation situation established by SV40 LT, one can investigate the tumor-related pathway involved in tumorigenesis by using Apoptin as a sensor. This study mainly focuses on the application of Apoptin in anti-tumor therapy and tumorigenesis in which Apoptin is involved.
Hepatocellular carcinoma (HCC) is one of the most common malignancies in the world and among the most fatal of human neoplasms. To improve the potential of a therapy against hepatocarcinoma based on Apoptin gene expression, one needs to develop systemic delivery vehicles, which can selectively deliver the Apoptin gene to liver (tumor) cells. The asialoglycoprotein receptor (ASGPR) is specially and abundantly expressed on the surface of normal hepatocytes as well as hepatocarcinoma cells. DNA plasmids, which have been coupled to the ASGPR ligand asialoglycoprotein (Asor) via poly-L-lysine linkers (PLL), can be selectively taken up by hepatocytes and hepatocarcinoma cells both in vitro. In this study, we have constructed a novel hepatic systemic delivery vehicle, Asor–Apoptin, which consists of Asor, PLL, and the plasmid pcDNA-vp3 encoding Apoptin. Particularly, in vivo studies demonstrate that the Asor–Apoptin complexes deliver the Apoptin gene specifically to hepatocytes and to in situ hepatocarcinoma, resulting in tumor regression without side effects on normal hepatocytes, which thus strongly suggests the effectiveness and perspectives of systemic delivery of Asor–Apoptin for therapeutic treatment of HCC-derived tumors. Our results have significant contribution to the further clinic application of Apoptin.
On the other hand, Apoptin can also be applied in the study on tumor-related pathway as a tumor specific death inducer. Recently it’s shown that Apoptin is phosphorylated at Thr108 specifically in human tumor and transformed cells, but not in human normal cells both in vivo and in vitro. Phosphorylated Apoptin translocates to nucleus rapidly and induces apoptosis subsequently specifically in tumor or transformed cells, whereas it remains unphosphorylated state and localizes mainly in cytoplasm without apoptosis inducing. Therefore, it has been thought that in tumor or transformed cells there exists a common tumor related phosphatase which phosphorylates Apoptin.
Moreover, Apoptin can also be activated by the transient transformation signals conferred by SV40 large T antigen (LT), which rapidly induces Apoptin’s three tumor-specific properties, phosphorylation, nuclear translocation and apoptosis induction. Thus, under the transient transformation situation established by SV40 LT, one can investigate the tumor-related pathway by using Apoptin as a sensor. Previous study demonstrated that the truncated N-terminal determinant of LT (LT136/st, encoding N-terminal of LT as well as small t antigen) was sufficient to confer Apoptin three of its tumor-specific properties, phosphorylation, nuclear translocation and apoptosis induction. In this study, we reported the role of related domains of N terminal determinant of SV40 T antigen in the activation of Apoptin. First, the PP2A binding domain of SV40 small tumor antigen (st) plays a vital role in the activation of tumor-related pathway sensed by Apoptin. However, st lacking its own nuclear localization signal has to be translocated to nucleus for Apoptin’s activation.
In addition, J domain shared by both LT136 and st is structurally needed. The first 1-82 amino acids (Hsc70 binding domain, that is, J domain) of LT136 and st are identical each other. It has been reported that Hsc70 (Heat shock protein cognate 70) can self-associate into dimmers or oligomers via their COOH-terminal peptide binding domain. Therefore, it’s possible that the two Hsc70 molecule which binds to J domain of LT136 and st respectively can self-associate into the compounds which contains two Hsc70 molecule and its binding proteins, LT136 and st. By the nuclear localization signal (NLS) of LT136 or the NLS of pRb which binds to LT136, these compounds containing st were targeted to nucleus, where the activity of PP2A was inhibited by its association with st and in turn altered or activated tumor-related pathway. Subsequently, the tumor-related kinase was activated rapidly, which phosphorylated and activated Apoptin. Taken together, our data first reveal that st is targeted to nucleus and inactivates PP2A by its association with st, which consequently activates tumor-related pathway sense by Apoptin. This tumor-related pathway is thought to be activated in the early stage of tumorigenesis and exists during the whole process of tumor formation. Our data also indicate that PP2A plays a crucial role in the early stage of cellular transformation and tumorigenesis.
Taken together, this study investigated the application of Apoptin in cancer gene therapy and tumorigenesis. We established a systemic Apoptin gene delivery vehicle, Asor-Apoptin, which was specifically targeted to hepatocytes as well as hepatocarcinoma cells and subsequently induced apoptosis of tumor cells without any toxicity to normal cells or normal tissues both in vivo and in vitro. These results established determinate foundation for further application in clinic. We also studied on tumor-related pathway by using Apoptin as a sensor and found the key molecule involved in the early stage of celluar transformation or tumorigenesis, which thus contributes to further research on tumorigenesis. The results from this study have been first reported by us, which provided valuable theory reference and experimental data for further study on Apoptin.
肝癌是世界上最常见也是最严重的恶性肿瘤之一。为了更好的将Apoptin用于肝癌的基因治疗,需要建立一种靶向性基因转导工具,特异性将Apoptin基因转移到肝细胞/肝癌细胞内。脱唾液酸糖蛋白受体(Asialoglycoprotein receptor, ASGPR)特异性地表达在肝细胞膜表面。体外和体内实验证明,通过多聚左旋赖氨酸(poly-L-lysine,PLL)与ASGPR的配体脱唾液酸糖蛋白(Asialoglycoprotein, Asor)相连接的DNA质粒,能够选择性被肝细胞所摄取。在本研究中,我们构建了由Asor,PLL和Apoptin表达质粒pcDNA-vp3组成的Asor-Apoptin肝细胞靶向性转导载体。体内实验证明,通过Asor-Apoptin转导系统,Apoptin基因可以被特异性地转移到肝细胞和原位肝癌细胞内,诱导肝肿瘤细胞凋亡,使肝脏肿瘤显著消退,并且对正常肝细胞无明显副作用,是一种有效的、很有应用前景的肝脏肿瘤治疗手段。这一研究成果对于Apoptin的临床应用具有重要意义。
另一方面,作为肿瘤特异性的细胞凋亡素,Apoptin同样在肿瘤相关信号通路的研究中具有重要的作用。体内和体外研究发现,在人肿瘤细胞及转化细胞内Apoptin108位苏氨酸被特异性磷酸化,Apoptin迅速移位到细胞核并诱导肿瘤细胞凋亡;而在人正常细胞内Apoptin则处于未磷酸化状态,停留在细胞质,也不诱导细胞凋亡。因此认为,在肿瘤及转化细胞内,普遍存在着一种与肿瘤相关的磷酸激酶,将Apoptin特异性磷酸化激活。
不仅如此,Apoptin还能被SV40大T抗原(LT)所建立的细胞瞬时转化状态所激活。以SV40早期基因产物(大T抗原和小T抗原)所建立的瞬时转化作为细胞模型,以Apoptin作为细胞转化或肿瘤发生的特异性感应蛋白,可以应用于肿瘤相关的信号通路的研究。前期研究表明,截短的N端SV40 T抗原(LT136/st,N端大T抗原LT136和全长小T抗原st)就能够替代全长大T抗原LT以激活Apoptin。我们进一步观察了N端T抗原的相关功能域在Apoptin激活效应中所起的作用。结果显示:SV40小T抗原(st) C端的PP2A结合功能域对Apoptin感应的肿瘤相关通路,起关键作用。有趣的是,本身不具有核定位作用的st(具有PP2A结合功能域)需要定位到细胞核才能激活Apoptin。
另外,共存于LT136和st的N端J功能域在结构上是必需的。LT136和st在其N端都具有完全相同的Hsc70结合功能域(即J功能域,1-82氨基酸)。据报道,Hsc70(热休克蛋白类似物)分子通过其C端的多肽结合功能域发生自结合,在细胞内以二聚体或多聚体的形式稳定存在。因此,我们推测,分别与LT136的J domain和st的J domain相结合两个相同的Hsc70分子有可能发生自结合,形成包括两个Hsc70分子、LT136和st的复合体。依靠LT136本身的NLS、或者与LT136所结合的pRb的NLS的核定位作用,这个包含st的复合体被定位到细胞核。在核基质中,st与PP2A相结合并抑制PP2A的生物活性,从而改变或者激活Apoptin所感应的肿瘤相关信号通路,Apoptin的肿瘤特异性磷酸激酶被激活,进而将Apoptin特异性磷酸化激活。研究结果表明,SV40小T抗原(st)被定位到细胞核,与PP2A结合并抑制PP2A的生物活性,诱导Apoptin感应的肿瘤相关信号通路的激活。该信号通路可能在肿瘤发生的早期阶段激发,并持续作用于肿瘤发生过程。PP2A可能是细胞转化乃至肿瘤发生较早期阶段的关键分子靶点,在肿瘤发生的较早期阶段发挥重要作用。
总之,本研究对Apoptin在肿瘤基因治疗和肿瘤发生机制研究中的应用两个方面进行了初步探讨。我们建立了一种肝细胞靶向性的Apoptin基因转导载体Asor-Apoptin,并且对其体内、体外的肝细胞靶向性和抑癌效应以及对正常组织细胞的毒副作用进行了观察。这一实验成果为进一步的临床应用奠定了基础。在肿瘤发生机制的研究中,我们用Apoptin作为肿瘤特异性的感应蛋白,对肿瘤相关的信号通路进行了初步探讨,进而提出细胞转化和肿瘤发生较早期阶段的关键分子靶点,为肿瘤发生机理的研究提供了有价值的实验依据。以上研究在国际上均未见报道,属于创新性研究探讨,它将为Apoptin的进一步深入研究提供实验及理论依据。
Apoptin, which is also named as VP3, is a small viral protein encoded by chicken anemia virus (CAV). The early study on Apoptin has shown that Apoptin induces apoptosis in a great variety of tumors (>70), as well as transformed cells. However, Apoptin does not induce significant apoptosis in human normal cells, including primary human hematopoietic stem CD34+ cells, primary human mesenchymal stem cells, or human primary hepatocytes. Human normal cells expressing Apoptin proliferate and divide regularly without any potential of transformation or toxicity. The normal development and growth of transgenic mice also prove that Apoptin is non-toxic to normal cells in vivo. Thus, Apoptin is a promising anti-tumor agent, which induces apoptosis in tumor or transformed cells but not in normal cells. Moreover, Apoptin can also be activated by the transient transforming signals conferred by SV40 LT (large tumor antigen). Under the transient transformation situation established by SV40 LT, one can investigate the tumor-related pathway involved in tumorigenesis by using Apoptin as a sensor. This study mainly focuses on the application of Apoptin in anti-tumor therapy and tumorigenesis in which Apoptin is involved.
Hepatocellular carcinoma (HCC) is one of the most common malignancies in the world and among the most fatal of human neoplasms. To improve the potential of a therapy against hepatocarcinoma based on Apoptin gene expression, one needs to develop systemic delivery vehicles, which can selectively deliver the Apoptin gene to liver (tumor) cells. The asialoglycoprotein receptor (ASGPR) is specially and abundantly expressed on the surface of normal hepatocytes as well as hepatocarcinoma cells. DNA plasmids, which have been coupled to the ASGPR ligand asialoglycoprotein (Asor) via poly-L-lysine linkers (PLL), can be selectively taken up by hepatocytes and hepatocarcinoma cells both in vitro. In this study, we have constructed a novel hepatic systemic delivery vehicle, Asor–Apoptin, which consists of Asor, PLL, and the plasmid pcDNA-vp3 encoding Apoptin. Particularly, in vivo studies demonstrate that the Asor–Apoptin complexes deliver the Apoptin gene specifically to hepatocytes and to in situ hepatocarcinoma, resulting in tumor regression without side effects on normal hepatocytes, which thus strongly suggests the effectiveness and perspectives of systemic delivery of Asor–Apoptin for therapeutic treatment of HCC-derived tumors. Our results have significant contribution to the further clinic application of Apoptin.
On the other hand, Apoptin can also be applied in the study on tumor-related pathway as a tumor specific death inducer. Recently it’s shown that Apoptin is phosphorylated at Thr108 specifically in human tumor and transformed cells, but not in human normal cells both in vivo and in vitro. Phosphorylated Apoptin translocates to nucleus rapidly and induces apoptosis subsequently specifically in tumor or transformed cells, whereas it remains unphosphorylated state and localizes mainly in cytoplasm without apoptosis inducing. Therefore, it has been thought that in tumor or transformed cells there exists a common tumor related phosphatase which phosphorylates Apoptin.
Moreover, Apoptin can also be activated by the transient transformation signals conferred by SV40 large T antigen (LT), which rapidly induces Apoptin’s three tumor-specific properties, phosphorylation, nuclear translocation and apoptosis induction. Thus, under the transient transformation situation established by SV40 LT, one can investigate the tumor-related pathway by using Apoptin as a sensor. Previous study demonstrated that the truncated N-terminal determinant of LT (LT136/st, encoding N-terminal of LT as well as small t antigen) was sufficient to confer Apoptin three of its tumor-specific properties, phosphorylation, nuclear translocation and apoptosis induction. In this study, we reported the role of related domains of N terminal determinant of SV40 T antigen in the activation of Apoptin. First, the PP2A binding domain of SV40 small tumor antigen (st) plays a vital role in the activation of tumor-related pathway sensed by Apoptin. However, st lacking its own nuclear localization signal has to be translocated to nucleus for Apoptin’s activation.
In addition, J domain shared by both LT136 and st is structurally needed. The first 1-82 amino acids (Hsc70 binding domain, that is, J domain) of LT136 and st are identical each other. It has been reported that Hsc70 (Heat shock protein cognate 70) can self-associate into dimmers or oligomers via their COOH-terminal peptide binding domain. Therefore, it’s possible that the two Hsc70 molecule which binds to J domain of LT136 and st respectively can self-associate into the compounds which contains two Hsc70 molecule and its binding proteins, LT136 and st. By the nuclear localization signal (NLS) of LT136 or the NLS of pRb which binds to LT136, these compounds containing st were targeted to nucleus, where the activity of PP2A was inhibited by its association with st and in turn altered or activated tumor-related pathway. Subsequently, the tumor-related kinase was activated rapidly, which phosphorylated and activated Apoptin. Taken together, our data first reveal that st is targeted to nucleus and inactivates PP2A by its association with st, which consequently activates tumor-related pathway sense by Apoptin. This tumor-related pathway is thought to be activated in the early stage of tumorigenesis and exists during the whole process of tumor formation. Our data also indicate that PP2A plays a crucial role in the early stage of cellular transformation and tumorigenesis.
Taken together, this study investigated the application of Apoptin in cancer gene therapy and tumorigenesis. We established a systemic Apoptin gene delivery vehicle, Asor-Apoptin, which was specifically targeted to hepatocytes as well as hepatocarcinoma cells and subsequently induced apoptosis of tumor cells without any toxicity to normal cells or normal tissues both in vivo and in vitro. These results established determinate foundation for further application in clinic. We also studied on tumor-related pathway by using Apoptin as a sensor and found the key molecule involved in the early stage of celluar transformation or tumorigenesis, which thus contributes to further research on tumorigenesis. The results from this study have been first reported by us, which provided valuable theory reference and experimental data for further study on Apoptin.
引文
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11 Van der Eb MM, Pietersen AM, Speetjens FM, Kuppen PJ, van de Velde CJ, Noteborn MH et al. Gene therapy with Apoptin induces regression of xenografted human hepatomas. Cancer Gene Ther 2002; 9: 53–61.
12 Smith RM, Wu GY. Hepatocyte-directed gene delivery by receptor-mediated endocytosis. Semin Liver Dis 1999; 19: 83–92.
13 Singh M, Ariatti M. Targeted gene delivery into HepG2 cells using complexes containing DNA, cationized asialoorosomucoid and activated cationic liposomes. J Control Rel 2003; 92: 383–394.
14 Singh M, Kisoon N, Ariatti M. Receptor-mediated gene delivery to HepG2 cells by ternary assemblies containing cationic liposomes and cationized asialoorosomucoid. Drug Deliv 2001; 8: 29–34.
15 Davis BG, Robinson MA. Drug delivery systems based on sugar–macromolecule conjugates. Curr Opin Drug Discov Dev 2002; 5: 279–288.
16 Van Rossenberger SM, Sliedregt-Bol KM, Meeuwenoord NJ, van Berkel TJ, van Boom JH, van der Marel GA. Targeted lysosome disruptive elements for improvement of parenchymal liver cell-specific gene delivery. J Biol Chem 2002; 277: 45803–45810.
17 Ghosh SS, Takahashi M, Thumala NR, Parashar B, Chowdhury NR, Chowdhury JR. Liver-directed genetherapy: promises, problems and prospects at the turn of the century. J Hepatol 2000; 32: 238–252.
18 McKee TD, DeRome ME, Wu GY, Findeis MA. Preparation of asialoorosomucoid–polylysine conjugates. Bioconjugate Chem 1994; 5: 306–311.
19 Kwoh DY, Coffin CC, Lollo CP, Jovenal J, Banaszczyk MG, Mullen P et al. Stabilization of poly-L-lysine/DNA polyplexes for in vivo gene delivery to the liver. Biochim Biophys Acta 1999; 1444: 171–190.
20 Han J, Il Yeom Y. Specific gene transfer mediated by galactosylated poly-L-lysine into hepatoma cells. Int J Pharmacol 2000; 202: 151–160.
21 Lochmann D, Jauk E, Zimmer A. Drug delivery of oligonucleotides by peptides. Eur J Pharm Biopharm 2004; 58: 237–251.
22 Trere D, Fiume L, De Giorgi LB, Di Stefano G, Migaldi M, Derenzini M. The asialoglycoprotein receptor in human hepatocellular carcinomas: its expression on proliferating cells. Br J Cancer 1999; 81: 404–408.
23 Mok TS, Leung TW, Brown G, Moyses C, Chan AT, Yeo W et al. A phase I safety and pharmacokinetic study of OGT 719 in patients with liver cancer. Acta Oncol 2004; 43: 245–251.
24 Havlik R, Kral V, Habib N. Gene therapy of liver tumors: results of the first clinical studies. Cas Lek Cesk 2003; 142: 370–528.
25 Zhu AX. Hepatocellular carcinoma: are we making progress? Cancer Invest 2003; 21: 418–428.
26 Tang Z-Y. Hepatocellular carcinoma– cause, treatment and metastasis. World J Gastroenterol 2001; 7: 445–454.
27 Kountouras J, Zavos C, Chatzopoulos D. Apoptosis in hepatocellular carcinoma. Hepatogastroenterology 2003; 50: 242–249.
28 Bantel H, Schulze-Osthoff K. Apoptosis in hepatitis C virus infection. Cell Death Differ 2003; 10: S48–58.
29 Suriawinata A, Xu R. An update on the molecular genetics of hepatocellular carcinoma. Semin Liver Dis 2004; 24: 77–88.
30 Watanabe J, Kushihata F, Honda K, Sugita A, Tateishi N, Mominoki K et al. Prognostic significance of Bcl-xL in human hepatocellular carcinoma. Surgery 2004; 135: 604–612.
31 Chun E, Lee KY. Bcl-2 and Bcl-xL are important for the induction of paclitaxel resistance in human hepatocellular carcinoma cells. Biochem Biophys Res Commun 2004; 315: 771–779.
32 Takehara T, Takahashi H. Suppression of Bcl-xL deamidation in human hepatocellular carcinomas. Cancer Res 2003; 63: 3054–3057.
33 Noteborn MH. Apoptin acts as a tumor-specific killer: potentials for an anti-tumor therapy. Cell Mol Biol 2005; 51: 49–60.
34 Pietersen AM. Preclinical studies with Apoptin. PhD thesis, Erasmus University, Rotterdam, The Netherlands, 2003.
35 Maddika S, Booy EP, Johar D, Gibson SB, Ghavami S, Los M. Cancer-specific toxicity of apoptin is independent of death receptors but involves the loss of mitochondrial membrane potential and the release of mitochondrial celldeath mediators by a Nur77-dependent pathway. J Cell Sci 2005; 118: 4485–4493.
1. Noteborn, M. H. M., G. F. de Boer, D. J. van Roozelaar, C. Karreman, O. Kranenburg, J. G. Vos, S. H. M. Jeurissen, R. C. Hoeben, A. Zantema, G. Koch, H. van Ormondt, and A. J. van der Eb. 1991. Characterization of cloned chicken anemia virus DNA that contains all elements for the infectious replication cycle. J. Virol 65:3131–3139.
2. Noteborn, M. H. M., and G. Koch. 1995. Chicken anemia virus infection: molecular basis of pathogenicity. Avian Pathol. 24:11–31.
3. Noteborn, M. H. M., A. A. A. M. Danen-van Oorschot, and A. J. Van der Eb. 1998. Chicken anemia virus: induction of apoptosis by a single protein of a single-stranded DNA virus. Semin. Virol. 8:497–504.
4. Noteborn, M. H. M., D. Todd, C. A. Verschueren, H. W. de Gauw, W. L. Curran, S. Veldkamp, A. J. Douglas, M. S. McNulty, A. J. van der Eb, and G. Koch. 1994. A single chicken anemia virus protein induces apoptosis. J. Virol. 68:346–351.
5. Noteborn, M. H. M., A. J. van der Eb, G. Koch, and S. H. M. Jeurissen. 1993. VP3 of the chicken anemia virus (CAV) causes apoptosis, p. 299–304. In H. S. Ginsberg, F. Brown, R. M. Chanock, and R. A. Lerner (ed.), Vaccines.93: modern approach to new vaccines including prevention of AIDS. Cold Spring Harbor Laboratory Press, Cold Spring Harbor, N.Y.
6. Danen-van Oorschot, A. A. A. M., D. Fischer, J. M. Grimbergen, B. Klein, S.-M. Zhuang, J. H. F. Falkenburg, C. Backendorf, P. H. A. Quax, A. J. Van der Eb, and M. H. M. Noteborn. 1997. Apoptin induces apoptosis in human transformed and malignant cells but not in normal cells. Proc. Natl. Acad. Sci. USA 94:5843–5847.
7. Zhuang, S.-M., J. E. Landegent, C. A. Verschueren, J. H. Falkenburg, H. van Ormondt, A. J. van der Eb, and M. H. M. Noteborn. 1995. Apoptin, a protein encoded by chicken anemia virus, induces cell death in various human hematologic malignant cells in vitro. Leukemia 9(Suppl. 1):S118–S120.
8. Zhuang, S.-M., A. Shvarts, H. van Ormondt, A. G. Jochemsen, A. J. van der Eb, and M. H. M. Noteborn. 1995. Apoptin, a protein derived from chicken anemia virus, induces p53-independent apoptosis in human osteosarcoma cells. Cancer Res. 55:486–489.
9. Danen-van Oorschot, A. A. A. M., Y.-H. Zhang, S. R. Leliveld, J. L. Rohn, M. C. M. J. Seelen, M. W. Bolk, A. Van Zon, S. J. Erkeland, J.-P. Abrahams, D. Mumberg, and M. H. M. Noteborn. 2003. Importance of nuclear localization of Apoptin for tumor-specific induction of apoptosis. J. Biol. Chem. 278:27729–27736.
10. Zhang, Y.-H., S. R. Leliveld, K. Kooistra, C. Molenaar, J. L. Rohn, H. J. Tanke, J. P. Abrahams, and M. H. M. Noteborn. 2003. Recombinant apoptin multimers kill tumor cells but are nontoxic and epitope-shielded in a normalcell-specific fashion. Exp. Cell. Res. 289:36–46.
11. Sa′enz-Robles, M. T., C. Sullivan, and J. M. Pipas. 2001. Transforming functions of simian virus 40. Oncogene 20:7899–7907.
12. Butel, J. S. 2000. Simian virus 40, poliovirus vaccines, and human cancer: research progress versus media and public interests. Bull. W. H. O. 78:195–198.
13. Butel, J. S., and J. A. Lednicky. 1999. Cell and Molecular biology of simian virus 40: implications for human infections and disease. J. Natl. Cancer Inst. 91:119–134.
14. Carbone, M., P. Fisso, and H. I. Pass. 1997. Simian virus 40, poliovaccines and human tumors: a review of recent developments. Oncogene 15:1877–1888.
15. Pipas, J. M., and A. J. Levine. 2001. Role of T antigen interactions with p53 in tumorigenesis. Semin. Cancer Biol. 11:23–30.
16. Sachsenmeier, K., and J. M. Pipas. 2001. Inhibition of Rb and p53 is insufficient for SV40 T-antigen transformation. Virology 283:40–48.
17. Sa′enz-Robles, M. T., C. Sullivan, and J. M. Pipas. 2001. Transforming functions of simian virus 40. Oncogene 20:7899–7907.
18. Mateer, S. C., S. A., Fedorow, and M.C. Mumby. 1998. Identification of Structural Elements Involved in the Interaction of Simian Virus 40 Small Tumor Antigen withProtein Phosphatase 2A. J. Biol. Chem. 253:35339-35346.
19. Sullivan, C.S., S.P. Gilbert, J.M. Pipas, 2001. ATP-dependent simian virus 40 T-antigen–Hsc70 complex formation. J. Virol. 75 (4), 1601–1610.
20. Hahn, W. C., S. K. Dessain, M. W. Brooks, J. E. King, B. Elenbaas, D. M. Sabatini, J. A. DeCaprio, and R. A. Weinberg. 2002. Enumeration of the simian virus 40 early region elements necessary for human cell transformation. Mol. Cell. Biol. 22:2111–2123.
21. Rundell, K., and R. Parakati. 2001. The role of the SV40 ST antigen in cell growth promotion and transformation. Semin. Cancer Biol. 11:5–13
22. Zhang, Y.-H., K. Kooistra, A. Pieterson, J. L., Rohn, and M. H. M. Noterborn. 2004. Activation of the Tumor-Specific Death Effector Apoptin and Its Kinase by an N-Terminal Determinant of Simian Virus 40 Large T Antigen. J. Virol. 78(18):9965-9976.
23. Rohn, J. L., Y.-H. Zhang, R. I. J. M. Aalbers, N. Otto, J. den Hertog, N. V. Henriquez, C. J. H. van de Velde, P. J. K. Kuppen, D. Mumberg, P. Donner, and M. H. M. Noteborn. 2002. A tumor-specific kinase activity regulates the viral death protein Apoptin. J. Biol. Chem. 277:50820–50827.
24. Stubdal, H., J. Zalvide, K. S. Campbell, C. Schweitzer, T. M. Roberts, and J. A. DeCaprio. 1997. Inactivation of pRb-related proteins p130 and p107 mediated by the J domain of simian virus 40 large T antigen. Mol. Cell. Biol. 17:4979–4990.
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27. Hu, W., B. E. Kemp, and D. A. Jans. 2005. Kinetic Properties of Nuclear TransportConferred by the Retinoblastoma (Rb) NLS. J. Cell. Biol. 95: 782-793.
28. Janssens V., and J. Goris. 2001. Protein phosphatase 2A: a highly regulated family of serine/threonine phosphatase implicated in cell growth and signalling. Biochem. J. 353:417-439
29. Calin, G. A., M. G. di Iasio, E. Caprini, I. Vorechovsky, P. G. Natali, G. Sozzi, C. M. Croce, G. Barbanti-Brodano, G. Russo, and M. Negrini. 2000. Low frequency of alterations of the alpha (PPP2R1A) and beta (PPP2R1B) isoforms of the subunit A of the serine-threonine phosphatase 2A in human neoplasms. Oncogene 19:1191–1195
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32. Benaroudj, N., B. Fouchaq, and M. M. Ladjimi. (1997) The COOH-terminal peptide binding domain is essential for self association of the molecular chaperone HSC70. J. Biol. Chem. 272: 8744–8751
33. Fouchaq, B., N. Benaroudj, C. Ebel, and M. M. Ladjimi. (1999) Oligomerization of the 17-kDa peptide-binding domain of the molecular chaperone HSC70. Eur. J. Biochem. 259: 379–384
34. Wang, T.F., J. -H. Chang, and C. Wang. (1993) Identification of the peptide binding domain of hsc70: 18-kilodalton fragment located immediately after ATPase domain is sufficient for high affinity binding. J. Biol. Chem. 268: 26049–26051
35. Nemotol, T. K., Y. Fukumal, H. Itoh, T. Takagi, and T. Ono. (2006) A Disulfide Bridge Mediated by Cysteine 574 Is Formed in the Dimer of the 70-kDa Heat Shock Protein. J. Biochem. 139:677-687.
1. Noteborn, M. H. M., and G. Koch. 1995. Chicken anemia virus infection: molecular basis of pathogenicity. Avian Pathol. 24:11–31.
2. Noteborn, M. H. M., D. Todd, C. A. Verschueren, H. W. de Gauw, W. L. Curran, S. Veldkamp, A. J. Douglas, M. S. McNulty, A. J. van der Eb, and G. Koch. 1994. A single chicken anemia virus protein induces apoptosis. J. Virol. 68:346–351.
3. Noteborn, M. H. M., G. F. de Boer, D. J. van Roozelaar, C. Karreman, O. Kranenburg, J. G. Vos, S. H. M. Jeurissen, R. C. Hoeben, A. Zantema, G. Koch, H. van Ormondt, and A. J. van der Eb. 1991. Characterization of cloned chicken anemia virus DNA that contains all elements for the infectious replication cycle. J. Virol 65:3131–3139.
4. Danen-van Oorschot, A. A. A. M., D. Fischer, J. M. Grimbergen, B. Klein, S.-M. Zhuang, J. H. F. Falkenburg, C. Backendorf, P. H. A. Quax, A. J. Van der Eb, and M. H. M. Noteborn. 1997. Apoptin induces apoptosis in human transformed and malignant cells but not in normal cells. Proc. Natl. Acad. Sci. USA 94:5843–5847.
5. Noteborn, M. H. M., A. A. A. M. Danen-van Oorschot, and A. J. Van der Eb. 1998. Chicken anemia virus: induction of apoptosis by a single protein of a single-stranded DNA virus. Semin. Virol. 8:497–504.
6. Noteborn, M. H. M., A. J. van der Eb, G. Koch, and S. H. M. Jeurissen. 1993. VP3 of the chicken anemia virus (CAV) causes apoptosis, p. 299–304. In H. S. Ginsberg, F. Brown, R. M. Chanock, and R. A. Lerner (ed.), Vaccines. 93: modern approach to new vaccines including prevention of AIDS. Cold Spring Harbor Laboratory Press, Cold Spring Harbor, N.Y.
7. Zhuang, S.-M., J. E. Landegent, C. A. Verschueren, J. H. Falkenburg, H. van Ormondt, A. J. van der Eb, and M. H. M. Noteborn. 1995. Apoptin, a protein encoded by chicken anemia virus, induces cell death in various human hematologic malignant cells in vitro. Leukemia 9(Suppl. 1):S118–S120.
8. Zhuang, S.-M., A. Shvarts, H. van Ormondt, A. G. Jochemsen, A. J. van der Eb, andM. H. M. Noteborn. 1995. Apoptin, a protein derived from chicken anemia virus, induces p53-independent apoptosis in human osteosarcoma cells. Cancer Res. 55:486–489.
9. Zhang, Y.-H., S. R. Leliveld, K. Kooistra, C. Molenaar, J. L. Rohn, H. J. Tanke, J. P. Abrahams, and M. H. M. Noteborn. 2003. Recombinant apoptin multimers kill tumor cells but are nontoxic and epitope-shielded in a normalcell-specific fashion. Exp. Cell. Res. 289:36–46.
10. Zhang, Y.-H., Activation of Apoptin, a tumor-specific viral death effector. PhD thesis, Leiden University, Leiden, The Netherlands, 2004.
11. Pietersen, A. M., Preclinical studies with Apoptin. PhD thesis, Erasmus University, Rotterdam, The Netherlands, 2003.
12. Zhang, Y.-H., P. J. Abrahams, A. J. van der Eb, and M. H. M. Noteborn. 1999. The viral protein Apoptin induces apoptosis in UV-C-irradiated cells from individuals with various hereditary cancer-prone syndromes. Cancer Res. 59:3010–3015.
13. Pietersen, A. M., M. M. van der Eb, H. J. Rademaker, et al. 1999 Specific tumor-cell killing with adenovirus vectors containing the apoptin gene. Gene Ther. 6:882–92.
14. Van der Eb MM, Pietersen AM, Speetjens F, et al. 2002. Gene therapy with Apoptin induces regression of xenografted human hepatomas. Cancer Gene Ther. 9: 53–61.
15. Peng D–J, J Sun, Y-Z Wang et al. 2007. Inhibition of hepatocarcinoma by systemic delivery of apoptin gene via asialoglycoprotein receptor. Cancer Gene Ther. 14: 66-73
16. Danen-van Oorschot, A. A. A. M., Y.-H. Zhang, S. R. Leliveld, J. L. Rohn, M. C. M. J. Seelen, M. W. Bolk, A. Van Zon, S. J. Erkeland, J.-P. Abrahams, D. Mumberg, and M. H. M. Noteborn. 2003. Importance of nuclear localization of Apoptin for tumor-specific induction of apoptosis. J. Biol. Chem. 278:27729–27736.
17. Leliveld, S. R., Y.-H. Zhang, L. R. Rohn, M. H. M. Noteborn, and J. P. Abrahams. 2003. Apoptin induces tumor-specific apoptosis as globular multimer. J. Biol. Chem. 278:9042–9051.
18. Leliveld, S.R., R. T. Dame, M. A. Mommaas, et al. 2003. Apoptin protein multimers form distinct higher-order nucleoprotein complexes with DNA. Nucleic Acid Res. 31: 4805–4813.
19. Danen-van Oorschot, A. A. A. M., Y.–H. Zhang, S. Erkeland, D. F. Fischer, A. J. Van der Eb, M. H. M. Noteborn. 1999. The effect of Bcl-2 on Apoptin in normal cells versus transformed human cells. Leukemia. 13: S75–S77.
20. Rohn, J. L., Y.-H. Zhang, R. I. J. M. Aalbers, N. Otto, J. den Hertog, N. V. Henriquez, C. J. H. van de Velde, P. J. K. Kuppen, D. Mumberg, P. Donner, and M. H. M. Noteborn. 2002. A tumor-specific kinase activity regulates the viral death protein Apoptin. J. Biol. Chem. 277:50820–50827.
21. Danen-van Oorschot, A. A. A. M., A. J. Van der Eb, M. H. M. Noteborn. 2000. The chicken anemia virus-derived protein Apoptin requires activation of caspases for induction of apoptosis in human tumor cells. J. Virol. 74:7072–7078.
22. Noteborn, M. H. M. 2004. Chicken anemia virus induced apoptosis: underlying molecular mechanisms. Veterinay Microbiology. 98:89-94.
23. Zhang, Y.-H., K. Kooistra, A. Pieterson, J. L., Rohn, and M. H. M. Noterborn. 2004. Activation of the Tumor-Specific Death Effector Apoptin and Its Kinase by an N-Terminal Determinant of Simian Virus 40 Large T Antigen. J. Virol. 78(18):9965-9976.
24. Srinivasan, A., A. J. McClellan, J. Vartikar, I. Marks, P. Cantalupo, Y. Li, P. Whyte, K. Rundell, J. L. Brodsky, and J. M. Pipas. 1997. The aminoterminal transforming region of simian virus 40 large T and small t antigen functions as a J domain. Mol. Cell. Biol. 17:4761–4773.
25. Benaroudj, N., B. Fouchaq, and M. M. Ladjimi. (1997) The COOH-terminal peptide binding domain is essential for self association of the molecular chaperone HSC70. J. Biol. Chem. 272: 8744–8751
26. Fouchaq, B., N. Benaroudj, C. Ebel, and M. M. Ladjimi. (1999) Oligomerization of the 17-kDa peptide-binding domain of the molecular chaperone HSC70. Eur. J.Biochem. 259: 379–384
27. Wang, T.F., J. -H. Chang, and C. Wang. (1993) Identification of the peptide binding domain of hsc70: 18-kilodalton fragment located immediately after ATPase domain is sufficient for high affinity binding. J. Biol. Chem. 268: 26049–26051
28. Janssens V., and J. Goris. 2001. Protein phosphatase 2A: a highly regulated family of serine/threonine phosphatase implicated in cell growth and signalling. Biochem. J. 353:417-439
29. Li, H.–H., X. Cai, G. P. Shouse, L. G. Piluso, and X. Liu. 2007. A specific PP2A regulatory subunit, B56γ, mediates DNA damage-induced dephosphorylation of p53 at Thr55. J. EMBO. 26:402-411.
2 Gerolami R, Uch R, Brechot C, Mannoni P, Pagnis C. Gene therapy of hepatocarcinoma: a long way from the concept to the therapeutical impact. Cancer Gene Ther 2003; 10: 649–660.
3 Rohn JL, Noteborn MHM. The viral death effector Apoptin reveals tumor-specific processes. Apoptosis 2004; 9: 315–322.
4 Tavassoli M, Guellen L, Luxon BA, Gaken J. Apoptin: specific killer of tumor cells? Apoptosis 2005; 10: 717–724.
5 Teodoro JG, Heilman DW, Parker AE, Green MR. The viral protein Apoptin associates with the anaphase-promoting complex to induce G2/M arrest and apoptosis in the absence of p53. Genes Dev 2004; 18: 1952–1957.
6 Guelen L, Paterson H, Gaeken J, Meyers M, Farzaneh F, Tavassoli M. TAT-Apoptin is efficiently delivered and induces apoptosis in cancer cells. Oncogene 2004; 23: 1153–1165.
7 Zhuang S-M, Shvarts A, Jochemsen AG, van Oorschot AA, van der Eb AJ, Noteborn MH. Differential sensitivity to Ad5 E1B-21kD and Bcl-2 proteins of Apoptin-induced versus p53-induced apoptosis. Carcinogenesis 1995; 16: 2939–2944.
8 Pietersen AM, Van der Eb MM, Rademaker HJ, van den Wollenberg DJ, Rabelink MJ, Kuppen PJ et al. Specific tumor-cell-killing with adenovirus vectors containing the apoptin gene. Gene Therapy 1999; 6: 882–892.
9 Shen Z, Wang Y, Zong Y, Qu S. Experimental study on the antitumor effect of chicken anemia virus vp3 gene against liver carcinoma in vivo. J Huazhong Univ Sci Technol Med Sci 2003; 23: 105–107, 115.
10 Zhang Y-H, Leliveld SR, Kooistra K, Molenaar C, Rohn JL, Tanke HJ et al. Recombinant Apoptin multimers kill tumor cells but are not-toxic and epitope-shielded in a normal-cell specific fashion. Exp Cell Res 2003; 289: 36–46.
11 Van der Eb MM, Pietersen AM, Speetjens FM, Kuppen PJ, van de Velde CJ, Noteborn MH et al. Gene therapy with Apoptin induces regression of xenografted human hepatomas. Cancer Gene Ther 2002; 9: 53–61.
12 Smith RM, Wu GY. Hepatocyte-directed gene delivery by receptor-mediated endocytosis. Semin Liver Dis 1999; 19: 83–92.
13 Singh M, Ariatti M. Targeted gene delivery into HepG2 cells using complexes containing DNA, cationized asialoorosomucoid and activated cationic liposomes. J Control Rel 2003; 92: 383–394.
14 Singh M, Kisoon N, Ariatti M. Receptor-mediated gene delivery to HepG2 cells by ternary assemblies containing cationic liposomes and cationized asialoorosomucoid. Drug Deliv 2001; 8: 29–34.
15 Davis BG, Robinson MA. Drug delivery systems based on sugar–macromolecule conjugates. Curr Opin Drug Discov Dev 2002; 5: 279–288.
16 Van Rossenberger SM, Sliedregt-Bol KM, Meeuwenoord NJ, van Berkel TJ, van Boom JH, van der Marel GA. Targeted lysosome disruptive elements for improvement of parenchymal liver cell-specific gene delivery. J Biol Chem 2002; 277: 45803–45810.
17 Ghosh SS, Takahashi M, Thumala NR, Parashar B, Chowdhury NR, Chowdhury JR. Liver-directed genetherapy: promises, problems and prospects at the turn of the century. J Hepatol 2000; 32: 238–252.
18 McKee TD, DeRome ME, Wu GY, Findeis MA. Preparation of asialoorosomucoid–polylysine conjugates. Bioconjugate Chem 1994; 5: 306–311.
19 Kwoh DY, Coffin CC, Lollo CP, Jovenal J, Banaszczyk MG, Mullen P et al. Stabilization of poly-L-lysine/DNA polyplexes for in vivo gene delivery to the liver. Biochim Biophys Acta 1999; 1444: 171–190.
20 Han J, Il Yeom Y. Specific gene transfer mediated by galactosylated poly-L-lysine into hepatoma cells. Int J Pharmacol 2000; 202: 151–160.
21 Lochmann D, Jauk E, Zimmer A. Drug delivery of oligonucleotides by peptides. Eur J Pharm Biopharm 2004; 58: 237–251.
22 Trere D, Fiume L, De Giorgi LB, Di Stefano G, Migaldi M, Derenzini M. The asialoglycoprotein receptor in human hepatocellular carcinomas: its expression on proliferating cells. Br J Cancer 1999; 81: 404–408.
23 Mok TS, Leung TW, Brown G, Moyses C, Chan AT, Yeo W et al. A phase I safety and pharmacokinetic study of OGT 719 in patients with liver cancer. Acta Oncol 2004; 43: 245–251.
24 Havlik R, Kral V, Habib N. Gene therapy of liver tumors: results of the first clinical studies. Cas Lek Cesk 2003; 142: 370–528.
25 Zhu AX. Hepatocellular carcinoma: are we making progress? Cancer Invest 2003; 21: 418–428.
26 Tang Z-Y. Hepatocellular carcinoma– cause, treatment and metastasis. World J Gastroenterol 2001; 7: 445–454.
27 Kountouras J, Zavos C, Chatzopoulos D. Apoptosis in hepatocellular carcinoma. Hepatogastroenterology 2003; 50: 242–249.
28 Bantel H, Schulze-Osthoff K. Apoptosis in hepatitis C virus infection. Cell Death Differ 2003; 10: S48–58.
29 Suriawinata A, Xu R. An update on the molecular genetics of hepatocellular carcinoma. Semin Liver Dis 2004; 24: 77–88.
30 Watanabe J, Kushihata F, Honda K, Sugita A, Tateishi N, Mominoki K et al. Prognostic significance of Bcl-xL in human hepatocellular carcinoma. Surgery 2004; 135: 604–612.
31 Chun E, Lee KY. Bcl-2 and Bcl-xL are important for the induction of paclitaxel resistance in human hepatocellular carcinoma cells. Biochem Biophys Res Commun 2004; 315: 771–779.
32 Takehara T, Takahashi H. Suppression of Bcl-xL deamidation in human hepatocellular carcinomas. Cancer Res 2003; 63: 3054–3057.
33 Noteborn MH. Apoptin acts as a tumor-specific killer: potentials for an anti-tumor therapy. Cell Mol Biol 2005; 51: 49–60.
34 Pietersen AM. Preclinical studies with Apoptin. PhD thesis, Erasmus University, Rotterdam, The Netherlands, 2003.
35 Maddika S, Booy EP, Johar D, Gibson SB, Ghavami S, Los M. Cancer-specific toxicity of apoptin is independent of death receptors but involves the loss of mitochondrial membrane potential and the release of mitochondrial celldeath mediators by a Nur77-dependent pathway. J Cell Sci 2005; 118: 4485–4493.
1. Noteborn, M. H. M., G. F. de Boer, D. J. van Roozelaar, C. Karreman, O. Kranenburg, J. G. Vos, S. H. M. Jeurissen, R. C. Hoeben, A. Zantema, G. Koch, H. van Ormondt, and A. J. van der Eb. 1991. Characterization of cloned chicken anemia virus DNA that contains all elements for the infectious replication cycle. J. Virol 65:3131–3139.
2. Noteborn, M. H. M., and G. Koch. 1995. Chicken anemia virus infection: molecular basis of pathogenicity. Avian Pathol. 24:11–31.
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1. Noteborn, M. H. M., and G. Koch. 1995. Chicken anemia virus infection: molecular basis of pathogenicity. Avian Pathol. 24:11–31.
2. Noteborn, M. H. M., D. Todd, C. A. Verschueren, H. W. de Gauw, W. L. Curran, S. Veldkamp, A. J. Douglas, M. S. McNulty, A. J. van der Eb, and G. Koch. 1994. A single chicken anemia virus protein induces apoptosis. J. Virol. 68:346–351.
3. Noteborn, M. H. M., G. F. de Boer, D. J. van Roozelaar, C. Karreman, O. Kranenburg, J. G. Vos, S. H. M. Jeurissen, R. C. Hoeben, A. Zantema, G. Koch, H. van Ormondt, and A. J. van der Eb. 1991. Characterization of cloned chicken anemia virus DNA that contains all elements for the infectious replication cycle. J. Virol 65:3131–3139.
4. Danen-van Oorschot, A. A. A. M., D. Fischer, J. M. Grimbergen, B. Klein, S.-M. Zhuang, J. H. F. Falkenburg, C. Backendorf, P. H. A. Quax, A. J. Van der Eb, and M. H. M. Noteborn. 1997. Apoptin induces apoptosis in human transformed and malignant cells but not in normal cells. Proc. Natl. Acad. Sci. USA 94:5843–5847.
5. Noteborn, M. H. M., A. A. A. M. Danen-van Oorschot, and A. J. Van der Eb. 1998. Chicken anemia virus: induction of apoptosis by a single protein of a single-stranded DNA virus. Semin. Virol. 8:497–504.
6. Noteborn, M. H. M., A. J. van der Eb, G. Koch, and S. H. M. Jeurissen. 1993. VP3 of the chicken anemia virus (CAV) causes apoptosis, p. 299–304. In H. S. Ginsberg, F. Brown, R. M. Chanock, and R. A. Lerner (ed.), Vaccines. 93: modern approach to new vaccines including prevention of AIDS. Cold Spring Harbor Laboratory Press, Cold Spring Harbor, N.Y.
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8. Zhuang, S.-M., A. Shvarts, H. van Ormondt, A. G. Jochemsen, A. J. van der Eb, andM. H. M. Noteborn. 1995. Apoptin, a protein derived from chicken anemia virus, induces p53-independent apoptosis in human osteosarcoma cells. Cancer Res. 55:486–489.
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