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Michele Carbone - One of the best experts on this subject based on the ideXlab platform.

  • SV40 and human mesothelioma.
    Translational lung cancer research, 2020
    Co-Authors: Michele Carbone, Adi F. Gazdar, Janet S. Butel
    Abstract:

    Simian virus 40 (SV40) is a DNA tumor virus capable of infecting and transforming human mesothelial (HM) cells in vitro. Hamsters injected intracardially to expose most tissue types to SV40 preferentially develop mesotheliomas. In humans, asbestos is the main cause of mesothelioma, and asbestos and SV40 are co-carcinogens in transforming HM cells in tissue culture and in causing mesothelioma in hamsters. Laser microdissection experiments conducted in the laboratory of Adi Gazdar demonstrated that SV40 was present specifically in the malignant mesothelioma cells and not in nearby stromal cells. Further experiments demonstrated that SV40 remains episomal in HM cells and astrocytes because of the production of a long antisense RNA that represses viral capsid protein production. Thus, the potent SV40 oncoprotein, T-antigen (Tag), is expressed, but because the capsid proteins are not produced, the cells are not lysed and, instead, become transformed. Together this evidence suggests that SV40 may contribute to the development of mesotheliomas in humans. However, epidemiological evidence to support this hypothesis is lacking. This chapter also summarizes the introduction of SV40, a monkey virus, into the human population as an unrecognized contaminant of early poliovaccines. In addition to mesotheliomas, SV40 now is linked with brain cancers, osteosarcomas, and lymphomas in humans. Explanations are provided for the apparent geographic variations in SV40 prevalence and for controversies about the role of SV40 in human cancer.

  • tissue tropism of SV40 transformation of human cells role of the viral regulatory region and of cellular oncogenes
    Genes & Cancer, 2010
    Co-Authors: Lei Zhang, Maurizio Bocchetta, Harvey I. Pass, Giovanni Gaudino, Oriana Strianese, Haining Yang, Paul Morris, Vivek R Nerurkar, Michele Carbone
    Abstract:

    SV40 has been detected prevalently in a limited panel of human tumors: mesothelioma, bone and brain tumors, and lymphoma. These are the same tumor types that are specifically induced by SV40 when injected into hamsters, a finding that has raised concerns about the possible pathogenic role of SV40 in humans. Two different SV40 isolates differing in the number of 72-bp elements in the virus regulatory region, archetypal SV40 (1ESV40), which contains one 72 bp, and nonarchetypal SV40 (wtSV40), which contains two 72 bp, have been detected in human tumors. 1ESV40 has been prevalently detected in brain tumors, with wtSV40 prevalently in mesothelioma. The apparent different cell tropism could be related to the virus (i.e., possibly to the number of 72-bp elements) and to different expression of cellular genes, known to play a critical role in SV40-mediated transformation of human cells, such as Notch-1 and c-Met. To test for possible differences in tissue tropism, we infected primary human mesothelial cells (HM) and primary human astrocytes (Ast) with 1ESV40 and with wtSV40 from 2 different SV40 strains, 776 and Baylor. All viruses transformed astrocytes; only wtSV40 transformed HM. Intracellular signaling of c-Met and Notch-1 was differently induced by these 2 viruses in HM and Ast. Differences in Notch-1 expression and signaling (i.e., downstream effectors, c-Myc, HEY-1, HES-1, and HEY-L) appeared to influence SV40-mediated transformation of primary astrocytes and mesothelial cells. Our results provide a biological rationale to the observation that 1ESV40 is prevalently detected in brain tumors and wtSV40 in mesotheliomas.

  • Simian virus 40 and cancer
    Oncology Reviews, 2007
    Co-Authors: Sandra Eliasz, Michele Carbone, Maurizio Bocchetta
    Abstract:

    Since its discovery in 1960 as a contaminant of poliovaccines, Simian Virus 40 (SV40) has been the object of extensive studies to assess whether this oncogenic virus plays a role in human carcinogenesis. Over the last two decades, this question has met with broad scepticism. However, there is increasing evidence linking SV40 to specific types of human cancer, especially malignant mesothelioma. Recently, two laboratories using different experimental approaches independently confirmed that SV40 acts synergistically with environmental fibers to promote mesothelial cell transformation and mesothelioma. Most of the scepticism concerning SV40 and cancer was due to the lack of clear epidemiologic data. However, it is still not clear how SV40 circulates in the human population, making the identification of SV40-exposed versus non-exposed cohorts problematic. Consequently, the most helpful insights into SV40-mediated carcinogenesis have come from molecular pathology, cell and molecular biology, and from animal studies.

  • some oral poliovirus vaccines were contaminated with infectious SV40 after 1961
    Cancer Research, 2005
    Co-Authors: Rochelle Cutrone, Maurizio Bocchetta, John A Lednicky, Glynis Dunn, Paola Rizzo, Konstantin Chumakov, Philip D Minor, Michele Carbone
    Abstract:

    Some polio vaccines prepared from 1954 to 1961 were contaminated with infectious SV40. It has been assumed that all polio vaccines were SV40 free in the United States after 1961 and in other countries after 1962. Following a WHO requirement that was prompted by the detection of SV40 in some human tumors, we conducted a multilaboratory study to test for SV40 polio vaccines prepared after 1961. Vaccine samples from 13 countries and the WHO seed were initially tested by PCR. The possible presence of intact and/or infectious SV40 DNA in PCR-positive samples was tested by transfection and infection of permissive CV-1 cells. All results were verified by immunohistochemistry, cloning, and sequencing. All the vaccines were SV40 free, except for vaccines from a major eastern European manufacturer that contained infectious SV40. We determined that the procedure used by this manufacturer to inactivate SV40 in oral poliovirus vaccine seed stocks based on heat inactivation in the presence of MgCl2 did not completely inactivate SV40. These SV40-contaminated vaccines were produced from early 1960s to about 1978 and were used throughout the world. Our findings underscore the potential risks of using primary monkey cells for preparing poliovirus vaccines, because of the possible contamination with SV40 or other monkey viruses, and emphasize the importance of using well-characterized cell substrates that are free from adventitious agents. Moreover, our results indicate possible geographic differences in SV40 exposure and offer a possible explanation for the different percentage of SV40-positive tumors detected in some laboratories.

  • new developments about the association of SV40 with human mesothelioma
    Oncogene, 2003
    Co-Authors: Michele Carbone, Harvey I. Pass, Lucio Miele, Maurizio Bocchetta
    Abstract:

    Simian virus 40 (SV40) has been detected in human tumors in over 40 different laboratories. Many of these reports linked SV40 to human mesotheliomas. The Vaccine Safety Committee of the Institute of Medicine (IOM), National Academy of Sciences, USA, recently reviewed the evidence associating polio vaccines and/or SV40 with human tumors. The IOM conclusions about polio vaccines and human cancer were: (1) 'the evidence is inadequate to accept or reject a causal relation between SV40-containing polio vaccines and cancer' because the 'epidemiological studies are sufficiently flawed'; (2) 'the biological evidence is of moderate strength that SV40 exposure from the polio vaccines is related to SV40 infection in humans'. The epidemiological studies were considered flawed because it was not possible to distinguish reliably among exposed and nonexposed cohorts. Concerning SV40, the IOM concluded that (1) 'the evidence is strong that SV40 is a transforming virus; (2) the evidence is of moderate strength that SV40 exposure could lead to cancer in humans under natural conditions' (IOM, 2002). Similar conclusions were reached at an International consensus meeting on SV40 and human tumors held at the University of Chicago in 2001. G Klein and C Croce, who chaired the final panel that reviewed all the published evidence linking SV40 to human tumors, stated that 'the presence of SV40 in human tumors has been convincingly demonstrated' (Klein et al., 2002). In addition, a workshop organized by the Biological Carcinogenesis Branch of the National Cancer Institute, Bethesda, MD, chaired by J Pagano, has reached similar conclusions (Wong et al., 2002). Therefore, three independent scientific panels have all agreed that there is compelling evidence that SV40 is present in some human cancers and that SV40 could contribute to the pathogenesis of some of them. It should be noted that the presence of SV40 in mesothelioma and other human tumor types has been challenged by a research team that has consistently reported negative findings (Strickler et al., 2001). However, a member of this research team has recently acknowledged - in sworn testimony -sensitivity problems and possible irregularities that raise concerns about these negative reports (MacLachlan, 2002). These revelations, together with the conclusions of the three independent panels mentioned above, appear to bring to an end the apparent controversy about the presence of SV40 in human mesotheliomas and brain tumors.

Mauro Tognon - One of the best experts on this subject based on the ideXlab platform.

  • SV40-immortalized human fibroblasts as a source of SV40 infectious virions.
    Molecular Medicine, 2004
    Co-Authors: Cristina Morelli, Federica Barbisan, Laura Iaccheri, Mauro Tognon
    Abstract:

    Human fibroblasts immortalized by Simian Virus 40 (SV40) are widely employed for cell and molecular biology model of study. Indeed, SV40 transmission to humans was believed to occur only under exceptional situations. The oncogenic potential of SV40 in laboratory animals is well established, whereas its involvement in human carcinogenesis is still a matter of active investigations. A recent report links SV40 exposure with the development of a brain tumor in a laboratory researcher. In previous studies, episomal viral DNA was detected in SV40 stably transformed and immortalized fibroblast cell lines. In this study, we report molecular and biological characterizations of SV40 DNA in human fibroblast cells. Our results indicate that SV40 is able to establish a persistent infection in long-term immortalized human fibroblasts, resulting in the production of an infectious viral progeny, which is able to infect both monkey and human cells. These data indicate that SV40-immortalized human fibroblasts may represent a source of SV40 infection. To avoid the SV40 infection, careful attention should be given by operators to this SV40-cell model of study.

  • SV40 replication in human mesothelial cells induces hgf met receptor activation a model for viral related carcinogenesis of human malignant mesothelioma
    Proceedings of the National Academy of Sciences of the United States of America, 2001
    Co-Authors: Paola Cacciotti, Mauro Tognon, Roberta Libener, Fernanda Martini, Piergiacomo Betta, Camillo Porta, Antonio Procopio, Luigi Strizzi, Lorenza Penengo, L Mutti
    Abstract:

    Recent studies suggested that simian virus 40 (SV40) may cause malignant mesothelioma, although the pathogenic mechanism is unclear. We found that in SV40-positive malignant mesothelioma cells, the hepatocyte growth factor (HGF) receptor (Met) was activated. In human mesothelial cells (HMC) transfected with full-length SV40 DNA (SV40-HMC), Met receptor activation was associated with S-phase entry, acquisition of a fibroblastoid morphology, and the assembly of viral particles. Coculture experiments revealed the ability of SV40-HMC to infect permissive monkey cells (CV-1), HMC, and murine BNL CL cells. Cocultured human and murine SV40-positive cells expressed HGF, showed Met tyrosine phosphorylation and S-phase entry, and acquired a spindle-shaped morphology (spBNL), whereas CV-1 cells were lysed. Cocultured HMC inherited from SV40-HMC the infectivity, as they induced lysis in cocultured CV-1 cells. Treatment with suramin or HGF-blocking antibodies inhibited Met tyrosine phosphorylation in all large T antigen (Tag)-positive cells and reverted the spindle-shaped morphology of spBNL. This finding indicated that Met activation and subsequent biological effects were mediated by an autocrine HGF circuit. This, in turn, was causally related to Tag expression, being induced by transfection with the SV40 early region alone. Our findings suggest that when SV40 infects HMC it causes Met activation via an autocrine loop. Furthermore, SV40 replicates in HMC and infects the adjacent HMC, inducing an HGF-dependent Met activation and cell-cycle progression into S phase. This may explain how a limited number of SV40-positive cells may be sufficient to direct noninfected HMC toward malignant transformation.

  • Association of SV40 with human tumours.
    Seminars in cancer biology, 2001
    Co-Authors: Bharat Jasani, Alfonso Cristaudo, Allen R. Gibbs, Adi F. Gazdar, Salih Emri, B. Krynska, C. Miller, Luciano Mutti, C. Radu, Mauro Tognon
    Abstract:

    SV40 was discovered as a contaminant of poliovirus vaccines that were inadvertently administered to millions of people in Europe and the United States between 1955 and 1963. Shortly afterwards, SV40 was proven to be oncogenic in rodents and capable of transforming human and animal cells in vitro. The possibility that SV40 might cause tumours in humans thus became a subject of scientific and public interest and scrutiny. However, largely due to a lack of significant epidemiological evidence, interest in assessing SV40's potential carcinogenic role in humans diminished. Recently, many laboratories have reported the presence of SV40-like DNA in a high proportion of human mesotheliomas, ependymomas and osteosarcoma (the three main types of tumours caused by virus in hamsters), renewing the question whether SV40 might be a human tumour virus. Molecular data from these studies are reviewed to re-evaluate the potential role of SV40 as a human carcinogen.

  • SV40 early region and large t antigen in human brain tumors peripheral blood cells and sperm fluids from healthy individuals
    Cancer Research, 1996
    Co-Authors: Fernanda Martini, Laura Iaccheri, L Lazzarin, Paolo Carinci, Alfredo Corallini, Massimo Gerosa, P Iuzzolino, Giuseppe Barbantibrodano, Mauro Tognon
    Abstract:

    SV40 T antigen (Tag) coding sequences were detected by PCR amplification followed by Southern blot hybridization in human brain tumors and tumor cell lines, as well as in peripheral blood cells and sperm fluids of healthy donors. SV40 early region sequences were found in 83% of choroid plexus papillomas, 73% of ependymomas, 47% of astrocytomas, 33% of glioblastoma multiforme cases, 14% of meningiomas, 50% of glioblastoma cell lines, and 33% of astrocytoma cell lines and in 23% of peripheral blood cell samples and 45% of sperm fluids from normal individuals. None of the 13 normal brain tissues were positive for SV40 DNA, nor were seven oligodendrogliomas, two spongioblastomas, one neuroblastoma, one meningioma, or four neuroblastoma cell lines. Expression of SV40 early region was found by reverse transcription PCR, and SV40-specific Tag was detected by indirect immunofluorescence in glioblastoma cell lines. DNA sequence analysis, performed in four positive samples, confirmed that the amplified PCR products belong to the SV40 early region. Sixty-one % of the neoplastic patients positive for SV40 sequences had an age excluding exposure to SV40-contaminated polio vaccines, suggesting a contagious transmission of SV40. The possible role of SV40 Tag in the etiopathogenesis of human brain tumors and the spread of SV40 by horizontal infection in the human population are discussed.

Maurizio Bocchetta - One of the best experts on this subject based on the ideXlab platform.

  • tissue tropism of SV40 transformation of human cells role of the viral regulatory region and of cellular oncogenes
    Genes & Cancer, 2010
    Co-Authors: Lei Zhang, Maurizio Bocchetta, Harvey I. Pass, Giovanni Gaudino, Oriana Strianese, Haining Yang, Paul Morris, Vivek R Nerurkar, Michele Carbone
    Abstract:

    SV40 has been detected prevalently in a limited panel of human tumors: mesothelioma, bone and brain tumors, and lymphoma. These are the same tumor types that are specifically induced by SV40 when injected into hamsters, a finding that has raised concerns about the possible pathogenic role of SV40 in humans. Two different SV40 isolates differing in the number of 72-bp elements in the virus regulatory region, archetypal SV40 (1ESV40), which contains one 72 bp, and nonarchetypal SV40 (wtSV40), which contains two 72 bp, have been detected in human tumors. 1ESV40 has been prevalently detected in brain tumors, with wtSV40 prevalently in mesothelioma. The apparent different cell tropism could be related to the virus (i.e., possibly to the number of 72-bp elements) and to different expression of cellular genes, known to play a critical role in SV40-mediated transformation of human cells, such as Notch-1 and c-Met. To test for possible differences in tissue tropism, we infected primary human mesothelial cells (HM) and primary human astrocytes (Ast) with 1ESV40 and with wtSV40 from 2 different SV40 strains, 776 and Baylor. All viruses transformed astrocytes; only wtSV40 transformed HM. Intracellular signaling of c-Met and Notch-1 was differently induced by these 2 viruses in HM and Ast. Differences in Notch-1 expression and signaling (i.e., downstream effectors, c-Myc, HEY-1, HES-1, and HEY-L) appeared to influence SV40-mediated transformation of primary astrocytes and mesothelial cells. Our results provide a biological rationale to the observation that 1ESV40 is prevalently detected in brain tumors and wtSV40 in mesotheliomas.

  • Simian virus 40 and cancer
    Oncology Reviews, 2007
    Co-Authors: Sandra Eliasz, Michele Carbone, Maurizio Bocchetta
    Abstract:

    Since its discovery in 1960 as a contaminant of poliovaccines, Simian Virus 40 (SV40) has been the object of extensive studies to assess whether this oncogenic virus plays a role in human carcinogenesis. Over the last two decades, this question has met with broad scepticism. However, there is increasing evidence linking SV40 to specific types of human cancer, especially malignant mesothelioma. Recently, two laboratories using different experimental approaches independently confirmed that SV40 acts synergistically with environmental fibers to promote mesothelial cell transformation and mesothelioma. Most of the scepticism concerning SV40 and cancer was due to the lack of clear epidemiologic data. However, it is still not clear how SV40 circulates in the human population, making the identification of SV40-exposed versus non-exposed cohorts problematic. Consequently, the most helpful insights into SV40-mediated carcinogenesis have come from molecular pathology, cell and molecular biology, and from animal studies.

  • some oral poliovirus vaccines were contaminated with infectious SV40 after 1961
    Cancer Research, 2005
    Co-Authors: Rochelle Cutrone, Maurizio Bocchetta, John A Lednicky, Glynis Dunn, Paola Rizzo, Konstantin Chumakov, Philip D Minor, Michele Carbone
    Abstract:

    Some polio vaccines prepared from 1954 to 1961 were contaminated with infectious SV40. It has been assumed that all polio vaccines were SV40 free in the United States after 1961 and in other countries after 1962. Following a WHO requirement that was prompted by the detection of SV40 in some human tumors, we conducted a multilaboratory study to test for SV40 polio vaccines prepared after 1961. Vaccine samples from 13 countries and the WHO seed were initially tested by PCR. The possible presence of intact and/or infectious SV40 DNA in PCR-positive samples was tested by transfection and infection of permissive CV-1 cells. All results were verified by immunohistochemistry, cloning, and sequencing. All the vaccines were SV40 free, except for vaccines from a major eastern European manufacturer that contained infectious SV40. We determined that the procedure used by this manufacturer to inactivate SV40 in oral poliovirus vaccine seed stocks based on heat inactivation in the presence of MgCl2 did not completely inactivate SV40. These SV40-contaminated vaccines were produced from early 1960s to about 1978 and were used throughout the world. Our findings underscore the potential risks of using primary monkey cells for preparing poliovirus vaccines, because of the possible contamination with SV40 or other monkey viruses, and emphasize the importance of using well-characterized cell substrates that are free from adventitious agents. Moreover, our results indicate possible geographic differences in SV40 exposure and offer a possible explanation for the different percentage of SV40-positive tumors detected in some laboratories.

  • new developments about the association of SV40 with human mesothelioma
    Oncogene, 2003
    Co-Authors: Michele Carbone, Harvey I. Pass, Lucio Miele, Maurizio Bocchetta
    Abstract:

    Simian virus 40 (SV40) has been detected in human tumors in over 40 different laboratories. Many of these reports linked SV40 to human mesotheliomas. The Vaccine Safety Committee of the Institute of Medicine (IOM), National Academy of Sciences, USA, recently reviewed the evidence associating polio vaccines and/or SV40 with human tumors. The IOM conclusions about polio vaccines and human cancer were: (1) 'the evidence is inadequate to accept or reject a causal relation between SV40-containing polio vaccines and cancer' because the 'epidemiological studies are sufficiently flawed'; (2) 'the biological evidence is of moderate strength that SV40 exposure from the polio vaccines is related to SV40 infection in humans'. The epidemiological studies were considered flawed because it was not possible to distinguish reliably among exposed and nonexposed cohorts. Concerning SV40, the IOM concluded that (1) 'the evidence is strong that SV40 is a transforming virus; (2) the evidence is of moderate strength that SV40 exposure could lead to cancer in humans under natural conditions' (IOM, 2002). Similar conclusions were reached at an International consensus meeting on SV40 and human tumors held at the University of Chicago in 2001. G Klein and C Croce, who chaired the final panel that reviewed all the published evidence linking SV40 to human tumors, stated that 'the presence of SV40 in human tumors has been convincingly demonstrated' (Klein et al., 2002). In addition, a workshop organized by the Biological Carcinogenesis Branch of the National Cancer Institute, Bethesda, MD, chaired by J Pagano, has reached similar conclusions (Wong et al., 2002). Therefore, three independent scientific panels have all agreed that there is compelling evidence that SV40 is present in some human cancers and that SV40 could contribute to the pathogenesis of some of them. It should be noted that the presence of SV40 in mesothelioma and other human tumor types has been challenged by a research team that has consistently reported negative findings (Strickler et al., 2001). However, a member of this research team has recently acknowledged - in sworn testimony -sensitivity problems and possible irregularities that raise concerns about these negative reports (MacLachlan, 2002). These revelations, together with the conclusions of the three independent panels mentioned above, appear to bring to an end the apparent controversy about the presence of SV40 in human mesotheliomas and brain tumors.

  • Notch-1 induction, a novel activity of SV40 required for growth of SV40-transformed human mesothelial cells
    Oncogene, 2003
    Co-Authors: Maurizio Bocchetta, Lucio Miele, Harvey I. Pass, Michele Carbone
    Abstract:

    We show that SV40 infection of human mesothelial cells directly causes overexpression of Notch-1, a key cell regulatory gene. Notch-1 induction is achieved at the transcriptional level and requires both the SV40 large T-antigen and the small t-antigen. Notch-1 upregulation is maintained in SV40-transformed human mesothelial clones and in SV40-positive mesotheliomas and derived cell lines. Activation of Notch-1 promotes cell cycle progression and it is required for the growth of SV40-transformed mesothelial cells. Our finding is relevant to the process of SV40-mediated human cell transformation, an effect that cannot be accounted for solely by SV40-Tag inhibition of Rb and p53.

Janet S. Butel - One of the best experts on this subject based on the ideXlab platform.

  • SV40 and human mesothelioma.
    Translational lung cancer research, 2020
    Co-Authors: Michele Carbone, Adi F. Gazdar, Janet S. Butel
    Abstract:

    Simian virus 40 (SV40) is a DNA tumor virus capable of infecting and transforming human mesothelial (HM) cells in vitro. Hamsters injected intracardially to expose most tissue types to SV40 preferentially develop mesotheliomas. In humans, asbestos is the main cause of mesothelioma, and asbestos and SV40 are co-carcinogens in transforming HM cells in tissue culture and in causing mesothelioma in hamsters. Laser microdissection experiments conducted in the laboratory of Adi Gazdar demonstrated that SV40 was present specifically in the malignant mesothelioma cells and not in nearby stromal cells. Further experiments demonstrated that SV40 remains episomal in HM cells and astrocytes because of the production of a long antisense RNA that represses viral capsid protein production. Thus, the potent SV40 oncoprotein, T-antigen (Tag), is expressed, but because the capsid proteins are not produced, the cells are not lysed and, instead, become transformed. Together this evidence suggests that SV40 may contribute to the development of mesotheliomas in humans. However, epidemiological evidence to support this hypothesis is lacking. This chapter also summarizes the introduction of SV40, a monkey virus, into the human population as an unrecognized contaminant of early poliovaccines. In addition to mesotheliomas, SV40 now is linked with brain cancers, osteosarcomas, and lymphomas in humans. Explanations are provided for the apparent geographic variations in SV40 prevalence and for controversies about the role of SV40 in human cancer.

  • Polyomavirus SV40 infections in Kazakhstan
    The Journal of infection, 2005
    Co-Authors: Zhannat Z. Nurgalieva, Connie Wong, Abai K. Zhangabylov, Zhazira E. Omarbekova, David Y. Graham, Regis A. Vilchez, Janet S. Butel
    Abstract:

    Abstract Objectives . To examine the prevalence of polyomavirus SV40 infections in Kazakhstan, a central Asian country known to have used potentially contaminated SV40 poliovaccines before 1962. Methods . Cross-sectional study of 307 healthy volunteers from two ethnic groups (Kazakhs and Russians) in Almaty, Kazakhstan, from May through August 1999 using a specific SV40 plaque-reduction neutralization assay. Results . Of the 307 volunteers enrolled in the study, 154 were Kazakhs and 153 were Russians. The overall prevalence of SV40 antibodies was 4.9%, and there was no significant difference between the ethnic groups ( p =0.7) or between males and females. The median SV40 neutralizing antibody titers in Kazakhs and Russians were 1:40 (range 1:10–1:500) and 1:20 (range 1:10–1:500), respectively. The median ages of SV40-infected Kazakhs and Russians were not different (42 vs. 24 years; p =0.1), although there was a trend for increased seropositivity among older Kazakhs. There was no difference in SV40 positivity between those whose childhoods were spent in rural or in urban areas ( p =0.4). Importantly, 60% (9/15) of the subjects seropositive for SV40 were born from 1969 to 1980s, when poliovaccines were free from SV40. Conclusions . This study showed evidence of polyomavirus SV40 infections in Kazakhstan, not only among individuals potentially exposed to contaminated poliovaccines, but in younger people not exposed to such vaccines. As increasing evidence indicates an association of SV40 with selected types of human malignancies, prospective studies are needed to examine the risk of SV40 infection with the development of neoplasias.

  • Association between SV40 and non-Hodgkin's lymphoma
    Leukemia & Lymphoma, 2003
    Co-Authors: Janet S. Butel, Regis A. Vilchez, Jeffrey L. Jorgensen, Claudia A. Kozinetz
    Abstract:

    Millions of people worldwide were inadvertently exposed to live simian virus 40 (SV40) between 1955 and 1963 through immunization with SV40-contaminated polio vaccines. Although the prevalence of SV40 infections in humans is not known, numerous studies suggest that SV40 is a pathogen resident in the human population today. SV40 is a potent DNA tumor virus that is known to induce primary brain cancers, bone cancers, mesotheliomas, and lymphomas in laboratory animals. SV40 oncogenesis is mediated by the viral large tumor antigen (T-ag), which inactivates the tumor suppressor proteins p53 and pRb. During the last decade, independent studies using different molecular biology techniques have shown the presence of SV40 DNA, T-ag, or other viral markers in primary human brain and bone cancers and malignant mesotheliomas. Evidence suggests that there may be geographic differences in the frequency of these virus-positive tumors. Recent large independent controlled studies have shown that SV40 T-ag DNA is significantly associated with human non-Hodgkin's lymphoma (NHL). In our study, we analyzed systemic NHL from 76 HIV-1-positive and 78 HIV-1-negative patients, and nonmalignant lymphoid samples from 79 HIV-1-positive and 107 HIV-1-negative patients without tumors; 54 colon and breast carcinoma samples served as cancer controls. We used polymerase chain reaction (PCR) followed by Southern blot hybridization and DNA sequence analysis to detect DNAs of polyomaviruses and herpesviruses. SV40-specific DNA sequences were detected in 64 (42%) of 154 NHL, none of 186 nonmalignant lymphoid samples, and none of 54 control cancers. For NHL from HIV-1-positive patients, 33% contained SV40 DNA and 39% Epstein Barr virus (EBV) DNA, whereas NHLs from HIV-1-negative patients were 50% positive for SV40 and 15% positive for EBV. Few tumors were positive for both SV40 and EBV. Human herpesvirus type 8 was not detected. SV40 sequences were found most frequently in diffuse large B cell and follicular-type lymphomas. We conclude that SV40 is significantly associated with some types of NHL and that lymphomas should be added to the types of human cancers associated with SV40.

  • cell and molecular biology of simian virus 40 implications for human infections and disease
    Journal of the National Cancer Institute, 1999
    Co-Authors: Janet S. Butel, John A Lednicky
    Abstract:

    Simian virus 40 (SV40), a polyomavirus of rhesus macaque origin, was discovered in 1960 as a contaminant of polio vaccines that were distributed to millions of people from 1955 through early 1963. SV40 is a potent DNA tumor virus that induces tumors in rodents and transforms many types of cells in culture, including those of human origin. This virus has been a favored laboratory model for mechanistic studies of molecular processes in eukaryotic cells and of cellular transformation. The viral replication protein, named large T antigen (T-ag), is also the viral oncoprotein. There is a single serotype of SV40, but multiple strains of virus exist that are distinguishable by nucleotide differences in the regulatory region of the viral genome and in the part of the T-ag gene that encodes the protein's carboxyl terminus. Natural infections in monkeys by SV40 are usually benign but may become pathogenic in immunocompromised animals, and multiple tissues can be infected. SV40 can replicate in certain types of simian and human cells. SV40-neutralizing antibodies have been detected in individuals not exposed to contaminated polio vaccines. SV40 DNA has been identified in some normal human tissues, and there are accumulating reports of detection of SV40 DNA and/or T-ag in a variety of human tumors. This review presents aspects of replication and cell transformation by SV40 and considers their implications for human infections and disease pathogenesis by the virus. Critical assessment of virologic and epidemiologic data suggests a probable causative role for SV40 in certain human cancers, but additional studies are necessary to prove etiology.

  • Evidence of SV40 infections in hospitalized children
    Human pathology, 1999
    Co-Authors: Janet S. Butel, Sanjeeda Jafar, Connie Wong, Amy S. Arrington, Antone R. Opekun, Milton J. Finegold, Ervin Adam
    Abstract:

    Simian virus 40 (SV40) is known to have contaminated poliovirus vaccines used between 1955 and 1963. Accumulating reports have described the presence of SV40 DNA in human tumors and normal tissues, although the significance of human infections by SV40 is unknown. We investigated whether unselected hospitalized children had evidence of SV40 infections and whether any clinical correlations were apparent. Serum samples were examined for SV40 neutralizing antibody using a specific plaque reduction test; of 337 samples tested, 20 (5.9%) had antibody to SV40. Seropositivity increased with age and was significantly associated with kidney transplants (6 of 15 [40%] positive, P < .001). Many of the antibody-positive patients had impaired immune systems. Molecular assays (polymerase chain reaction and DNA sequence analysis) on archival tissue specimens confirmed the presence of SV40 DNA in 4 of the antibody-positive patients. This study, using 2 independent assays, shows the presence of SV40 infections in children born after 1980. We conclude that SV40 causes natural infections in humans.

Harvey I. Pass - One of the best experts on this subject based on the ideXlab platform.

  • tissue tropism of SV40 transformation of human cells role of the viral regulatory region and of cellular oncogenes
    Genes & Cancer, 2010
    Co-Authors: Lei Zhang, Maurizio Bocchetta, Harvey I. Pass, Giovanni Gaudino, Oriana Strianese, Haining Yang, Paul Morris, Vivek R Nerurkar, Michele Carbone
    Abstract:

    SV40 has been detected prevalently in a limited panel of human tumors: mesothelioma, bone and brain tumors, and lymphoma. These are the same tumor types that are specifically induced by SV40 when injected into hamsters, a finding that has raised concerns about the possible pathogenic role of SV40 in humans. Two different SV40 isolates differing in the number of 72-bp elements in the virus regulatory region, archetypal SV40 (1ESV40), which contains one 72 bp, and nonarchetypal SV40 (wtSV40), which contains two 72 bp, have been detected in human tumors. 1ESV40 has been prevalently detected in brain tumors, with wtSV40 prevalently in mesothelioma. The apparent different cell tropism could be related to the virus (i.e., possibly to the number of 72-bp elements) and to different expression of cellular genes, known to play a critical role in SV40-mediated transformation of human cells, such as Notch-1 and c-Met. To test for possible differences in tissue tropism, we infected primary human mesothelial cells (HM) and primary human astrocytes (Ast) with 1ESV40 and with wtSV40 from 2 different SV40 strains, 776 and Baylor. All viruses transformed astrocytes; only wtSV40 transformed HM. Intracellular signaling of c-Met and Notch-1 was differently induced by these 2 viruses in HM and Ast. Differences in Notch-1 expression and signaling (i.e., downstream effectors, c-Myc, HEY-1, HES-1, and HEY-L) appeared to influence SV40-mediated transformation of primary astrocytes and mesothelial cells. Our results provide a biological rationale to the observation that 1ESV40 is prevalently detected in brain tumors and wtSV40 in mesotheliomas.

  • new developments about the association of SV40 with human mesothelioma
    Oncogene, 2003
    Co-Authors: Michele Carbone, Harvey I. Pass, Lucio Miele, Maurizio Bocchetta
    Abstract:

    Simian virus 40 (SV40) has been detected in human tumors in over 40 different laboratories. Many of these reports linked SV40 to human mesotheliomas. The Vaccine Safety Committee of the Institute of Medicine (IOM), National Academy of Sciences, USA, recently reviewed the evidence associating polio vaccines and/or SV40 with human tumors. The IOM conclusions about polio vaccines and human cancer were: (1) 'the evidence is inadequate to accept or reject a causal relation between SV40-containing polio vaccines and cancer' because the 'epidemiological studies are sufficiently flawed'; (2) 'the biological evidence is of moderate strength that SV40 exposure from the polio vaccines is related to SV40 infection in humans'. The epidemiological studies were considered flawed because it was not possible to distinguish reliably among exposed and nonexposed cohorts. Concerning SV40, the IOM concluded that (1) 'the evidence is strong that SV40 is a transforming virus; (2) the evidence is of moderate strength that SV40 exposure could lead to cancer in humans under natural conditions' (IOM, 2002). Similar conclusions were reached at an International consensus meeting on SV40 and human tumors held at the University of Chicago in 2001. G Klein and C Croce, who chaired the final panel that reviewed all the published evidence linking SV40 to human tumors, stated that 'the presence of SV40 in human tumors has been convincingly demonstrated' (Klein et al., 2002). In addition, a workshop organized by the Biological Carcinogenesis Branch of the National Cancer Institute, Bethesda, MD, chaired by J Pagano, has reached similar conclusions (Wong et al., 2002). Therefore, three independent scientific panels have all agreed that there is compelling evidence that SV40 is present in some human cancers and that SV40 could contribute to the pathogenesis of some of them. It should be noted that the presence of SV40 in mesothelioma and other human tumor types has been challenged by a research team that has consistently reported negative findings (Strickler et al., 2001). However, a member of this research team has recently acknowledged - in sworn testimony -sensitivity problems and possible irregularities that raise concerns about these negative reports (MacLachlan, 2002). These revelations, together with the conclusions of the three independent panels mentioned above, appear to bring to an end the apparent controversy about the presence of SV40 in human mesotheliomas and brain tumors.

  • Notch-1 induction, a novel activity of SV40 required for growth of SV40-transformed human mesothelial cells
    Oncogene, 2003
    Co-Authors: Maurizio Bocchetta, Lucio Miele, Harvey I. Pass, Michele Carbone
    Abstract:

    We show that SV40 infection of human mesothelial cells directly causes overexpression of Notch-1, a key cell regulatory gene. Notch-1 induction is achieved at the transcriptional level and requires both the SV40 large T-antigen and the small t-antigen. Notch-1 upregulation is maintained in SV40-transformed human mesothelial clones and in SV40-positive mesotheliomas and derived cell lines. Activation of Notch-1 promotes cell cycle progression and it is required for the growth of SV40-transformed mesothelial cells. Our finding is relevant to the process of SV40-mediated human cell transformation, an effect that cannot be accounted for solely by SV40-Tag inhibition of Rb and p53.

  • Simian virus 40 (SV40)-like DNA sequences not detectable in Finnish mesothelioma patients not exposed to SV40-contaminated polio vaccines
    Molecular carcinogenesis, 1999
    Co-Authors: Ari Hirvonen, Tapani Hovi, Harvey I. Pass, Karin Mattson, Antti Karjalainen, Tiina Ollikainen, L. Tammilehto, Harri Vainio, Ilaria Di Resta, Michele Carbone
    Abstract:

    Occupational asbestos exposure can be demonstrated in 80% of mesothelioma cases. A possible role of simian virus 40 (SV40) in the etiology of mesothelioma was raised because several studies reported the presence and expression of SV40-like DNA sequences in human mesotheliomas. It is also known that expression of SV40 large T antigen inhibits cellular Rb and p53. This suggests that SV40 might render infected cells more susceptible to asbestos carcinogenicity. The SV40-like sequences are suggested to have arisen from contaminated polio vaccines. Millions of people in the United States and most European countries were inoculated with SV40-contaminated polio vaccine in 1955–1963. However, in Finland, where polio vaccination started in 1957, no SV40-contaminated vaccine was used. We used a polymerase chain reaction–based method to test for the presence of SV40-like sequences in DNA extracted from the frozen tumor tissues of 49 Finnish mesothelioma patients, most of whom had been occupationally exposed to asbestos. All of the Finnish tumor tissues tested negative for SV40-like sequences. The results suggest that the SV40-like sequences detected in mesothelioma tissue in some previous studies may indeed originate from SV40-contaminated polio vaccines. It is a matter of speculation whether the absence of SV40 infection has contributed to the relatively low incidence of mesothelioma in Finland (1/105 in 1990–1995). Mol. Carcinog. 26:93–99, 1999. © 1999 Wiley-Liss, Inc.