Telomerase activation by the E6 gene product of human papillomavirus type 16.

Science.gov (United States)

Klingelhutz, A J; Foster, S A; McDougall, J K

1996-03-07

Activation of telomerase, a ribonucleoprotein complex that synthesizes telomere repeat sequences, is linked to cell immortalization and is characteristic of most cell lines and tumours. Here we show that expression of the human papillomavirus type 16 (HPV-16) E6 protein activates telomerase in early-passage human keratinocytes and mammary epithelial cells. This activation was observed in cells pre-crisis, that is, before they became immortal, and occurred within one passage of retroviral infection with vectors expressing HPV-16 E6. Studies using HPV-16 E6 mutants showed that there was no correlation between the ability of the mutants to activate telomerase and their ability to target p53 for degradation, suggesting that telomerase activation by HPV-16 E6 is p53 independent. Keratinocytes expressing wild-type HPV-16 E6 have an extended lifespan, but do not become immortal, indicating that telomerase activation and E6-mediate degradation of p53 are insufficient for their immortalization. These results show that telomerase activation is an intrinsic, but insufficient, component of transformation by HPV.

Intracellular scFvs against the viral E6 oncoprotein provoke apoptosis in human papillomavirus-positive cancer cells

International Nuclear Information System (INIS)

Lagrange, Magali; Boulade-Ladame, Charlotte; Mailly, Laurent; Weiss, Etienne; Orfanoudakis, Georges; Deryckere, Francois

2007-01-01

The E6 protein of human papillomavirus type 16 (16E6) is involved in the tumorigenesis of human cervical cells by targeting numerous cellular proteins. We have designed a strategy for neutralizing 16E6 based on the intracellular expression of single-chain Fv antibodies (scFvs) specific to 16E6. Recombinant adenovirus vectors were constructed to allow expression of two 16E6-binding scFvs and one 16E6-non-binding scFv in HPV16-positive and -negative cells. Expression of the scFvs provoked two types of effects: (i) inhibition of proliferation of all cell lines tested, this aspecific toxicity being likely due to the aggregation of unfolded scFvs; and (ii) apoptosis observed only in HPV16-positive cervical cancer cell lines after expression of 16E6-binding scFvs, this specific effect being proportional to the intracellular solubility of the scFvs. These data demonstrate the feasibility of intracellular immunization with anti-16E6 scFvs and highlight the importance of the solubility of the intracellular antibodies

Low- and high-risk human papillomavirus E7 proteins regulate p130 differently

International Nuclear Information System (INIS)

Barrow-Laing, Lisa; Chen Wei; Roman, Ann

2010-01-01

The E7 protein of high-risk human papillomaviruses (HR HPVs) targets pRb family members (pRb, p107 and p130) for degradation; low-risk (LR) HPV E7 only targets p130 for degradation. The effect of HR HPV 16 E7 and LR HPV 6 E7 on p130 intracellular localization and half-life was examined. Nuclear/cytoplasmic fractionation and immunofluorescence showed that, in contrast to control and HPV 6 E7-expressing cells, a greater amount of p130 was present in the cytoplasm in the presence of HPV 16 E7. The half-life of p130, relative to control cells, was decreased in the cytoplasm in the presence of HPV 6 E7 or HPV 16 E7, but only decreased by HPV 6 E7 in the nucleus. Inhibition of proteasomal degradation extended the half-life of p130, regardless of intracellular localization. These results suggest that there may be divergent mechanisms by which LR and HR HPV E7 target p130 for degradation.

Analysis of the roles of E6 binding to E6TP1 and nuclear localization in the human papillomavirus type 31 life cycle

International Nuclear Information System (INIS)

Lee, Choongho; Wooldridge, Tonia R.; Laimins, Laimonis A.

2007-01-01

The E6 oncoproteins of high-risk human papillomaviruses provide important functions not only for malignant transformation but also in the productive viral life cycle. E6 proteins have been shown to bind to a number of cellular factors, but only a limited number of analyses have investigated the effects of these interactions on the viral life cycle. In this study, we investigated the consequences of HPV 31 E6 binding to E6TP1, a putative Rap1 GAP protein. HPV 16 E6 has been shown to bind as well as induce the rapid turnover of E6TP1, and similar effects were observed with HPV 31 E6. Mutation of amino acid 128 in HPV 31 E6 was found to abrogate the ability to bind and degrade E6TP1 but did not alter binding to another α-helical domain protein, E6AP. When HPV 31 genomes containing mutations at amino acid 128 were transfected into human keratinocytes, the viral DNAs were not stably maintained as episomes indicating the importance of this residue for pathogenesis. Many E6 binding partners including E6TP1 are cytoplasmic proteins, but E6 has been also reported to be localized to the nucleus. We therefore investigated the importance of E6 localization to the nucleus in the viral life cycle. Using a fusion of E6 to Green Fluorescent Protein, we mapped one component of the nuclear localization sequences to residues 121 to 124 of HPV 31 E6. Mutation of these residues in the context of the HPV 31 genome abrogated the ability for episomes to be stably maintained and impaired the ability to extend the life span of cells. These studies identify two activities of HPV 31 E6 that are important for its function in the viral life cycle and for extension of cell life span

Human papillomavirus type 16 E6-specific antitumor immunity is induced by oral administration of HPV16 E6-expressing Lactobacillus casei in C57BL/6 mice.

Science.gov (United States)

Lee, Tae-Young; Kim, Yang-Hyun; Lee, Kyung-Soon; Kim, Jeong-Ki; Lee, Il-Han; Yang, Jai-Myung; Sung, Moon-Hee; Park, Jong-Sup; Poo, Haryoung

2010-11-01

Given that local cell-mediated immunity (CMI) against the human papillomavirus type 16 E6 (HPV16 E6) protein is important for eradication of HPV16 E6-expressing cancer cells in the cervical mucosa, the HPV16 E6 protein may be a target for the mucosal immunotherapy of cervical cancer. Here, we expressed the HPV16 E6 antigen on Lactobacillus casei (L. casei) and investigated E6-specific CMI following oral administration of the L. casei-PgsA-E6 to mice. Surface expression of HPV16 E6 antigens was confirmed and mice were orally inoculated with the L. casei-PgsA or the L. casei-PgsA-E6. Compared to the L. casei-PgsA-treated mice, significantly higher levels of serum IgG and mucosal IgA were observed in L. casei-PgsA-E6-immunized mice; these differences were significantly enhanced after boost. Consistent with this, systemic and local CMI were significantly increased after the boost, as shown by increased counts of IFN-gamma-secreting cells in splenocytes, mesenteric lymph nodes (MLN), and vaginal samples. Furthermore, in the TC-1 tumor model, animals receiving the orally administered L. casei-PgsA-E6 showed reduced tumor size and increased survival rate versus mice receiving control (L. casei-PgsA) immunization. We also found that L. casei-PgsA-E6-induced antitumor effect was decreased by in vivo depletion of CD4(+) or CD8(+) T cells. Collectively, these results indicate that the oral administration of lactobacilli bearing the surface-displayed E6 protein induces T cell-mediated cellular immunity and antitumor effects in mice.

Humoral immune response against proteins E6 and E7 in cervical carcinoma patients positive for human papilloma virus type 16 during treatment and follow-up

NARCIS (Netherlands)

Baay, M. F.; Duk, J. M.; Burger, M. P.; de Bruijn, H. W.; Stolz, E.; Herbrink, P.

1999-01-01

To investigate the humoral immune response to transforming proteins E6 and E7 of human papillomavirus type 16 before and after treatment and during follow-up, consecutive serum samples from 36 cervical cancer patients whose tumours were found to contain human papillomavirus type 16 DNA by use of the

Humoral immune response against proteins E6 and E7 in cervical carcinoma patients positive for human papilloma virus type 16 during treatment and follow-up

NARCIS (Netherlands)

Baay, MFD; Duk, JM; Burger, MPM; de Bruijn, HWA; Stolz, E; Herbrink, P

To investigate the humoral immune response to transforming proteins E6 and E7 of human papillomavirus type 16 before and after treatment and during follow-up, consecutive serum samples from 36 cervical cancer patients whose tumours were found to contain human papillomavirus type 16 DNA by use of the

Human Papillomavirus 16 (HPV-16), HPV-18, and HPV-31 E6 Override the Normal Phosphoregulation of E6AP Enzymatic Activity.

Science.gov (United States)

Thatte, Jayashree; Banks, Lawrence

2017-11-15

The human papillomavirus (HPV) E6 oncoproteins recruit the cellular ubiquitin ligase E6AP/UBE3A to target cellular substrates for proteasome-mediated degradation, and one consequence of this activity is the E6 stimulation of E6AP autoubiquitination and degradation. Recent studies identified an autism-linked mutation within E6AP at T485, which was identified as a protein kinase A phosphoacceptor site and which could directly regulate E6AP ubiquitin ligase activity. In this study, we have analyzed how T485-mediated regulation of E6AP might affect E6 targeting of some of its known substrates. We show that modulation of T485 has no effect on the ability of E6 to direct either p53 or Dlg for degradation. Furthermore, T485 regulation has no effect on HPV-16 or HPV-31 E6-induced autodegradation of E6AP but does affect HPV-18 E6-induced autodegradation of E6AP. In cells derived from cervical cancers, we find low levels of both phosphorylated and nonphosphorylated E6AP in the nucleus. However, ablation of E6 results in a dramatic accumulation of phospho-E6AP in the cytoplasm, whereas nonphosphorylated E6AP accumulates primarily in the nucleus. Interestingly, E6AP phosphorylation at T485 confers association with 14-3-3 proteins, and this interaction seems to be important, in part, for the ability of E6 to recruit phospho-E6AP into the nucleus. These results demonstrate that HPV E6 overrides the normal phosphoregulation of E6AP, both in terms of its enzymatic activity and its subcellular distribution. IMPORTANCE Recent reports demonstrate the importance of phosphoregulation of E6AP for its normal enzymatic activity. Here, we show that HPV E6 is capable of overriding this regulation and can promote degradation of p53 and Dlg regardless of the phosphorylation status of E6AP. Furthermore, E6 interaction with E6AP also significantly alters how E6AP is subject to autodegradation and suggests that this is not a simple stimulation of an already-existing activity but rather a

Human Papillomavirus type 16 E6 and E 7 proteins alter NF-kB in cultured cervical epithelial cells and inhibition of NF-kB promotes cell growth and immortalization

Science.gov (United States)

Vandermark, Erik R.; Deluca, Krysta A.; Gardner, Courtney R.; Marker, Daniel F.; Schreiner, Cynthia N.; Strickland, David A.; Wilton, Katelynn M.; Mondal, Sumona; Woodworth, Craig D.

2012-01-01

The NF-kB family of transcription factors regulates important biological functions including cell growth, survival and the immune response. We found that Human Papillomavirus type 16 (HPV-16) E7 and E6/E7 proteins inhibited basal and TNF-alpha-inducible NF-kB activity in human epithelial cells cultured from the cervical transformation zone, the anatomic region where most cervical cancers develop. In contrast, HPV-16 E6 regulated NF-kB in a cell type- and cell growth-dependent manner. NF-kB influenced immortalization of cervical cells by HPV16. Inhibition of NF-kB by an IkB alpha repressor mutant increased colony formation and immortalization by HPV-16. In contrast, activation of NF-kB by constitutive expression of p65 inhibited proliferation and immortalization. Our results suggest that inhibition of NF-kB by HPV-16 E6/E7 contributes to immortalization of cells from the cervical transformation zone. PMID:22284893

Direct Human Papillomavirus E6 Whole-Cell Enzyme-Linked Immunosorbent Assay for Objective Measurement of E6 Oncoproteins in Cytology Samples

OpenAIRE

Yang, Yi-Shan; Smith-McCune, Karen; Darragh, Teresa M.; Lai, Yvonne; Lin, Ju-Hwa; Chang, Ting-Chang; Guo, Hsiao-Yun; Kesler, Tiea; Carter, Alicia; Castle, Philip E.; Cheng, Shuling

2012-01-01

A novel, whole-cell enzyme-linked immunosorbent assay (ELISA) based on a non-type-specific anti-human papillomavirus (HPV) E6 antibody was tested on 182 residual cytological specimens. For samples with a designation of more severe than cervical intraepithelial neoplasia grade 3 (CIN3+), 83% tested positive for E6; in a subset with paired testing for E6 ELISA and HPV DNA, 72% tested E6 positive and 92% tested high-risk (HR)-HPV DNA positive (P = 0.2). Among the women with a less than CIN3 diag...

Adenovirus type 5 E1A and E6 proteins of low-risk cutaneous beta-human papillomaviruses suppress cell transformation through interaction with FOXK1/K2 transcription factors.

Science.gov (United States)

Komorek, Jessica; Kuppuswamy, Mohan; Subramanian, T; Vijayalingam, S; Lomonosova, Elena; Zhao, Ling-Jun; Mymryk, Joe S; Schmitt, Kimberly; Chinnadurai, G

2010-03-01

The adenovirus (Adv) oncoprotein E1A stimulates cell proliferation and inhibits differentiation. These activities are primarily linked to the N-terminal region (exon 1) of E1A, which interacts with multiple cellular protein complexes. The C terminus (exon 2) of E1A antagonizes these processes, mediated in part through interaction with C-terminal binding proteins 1 and 2 (CtBP1/2). To identify additional cellular E1A targets that are involved in the modulation of E1A C-terminus-mediated activities, we undertook tandem affinity purification of E1A-associated proteins. Through mass spectrometric analysis, we identified several known E1A-interacting proteins as well as novel E1A targets, such as the forkhead transcription factors, FOXK1/K2. We identified a Ser/Thr-containing sequence motif in E1A that mediated interaction with FOXK1/K2. We demonstrated that the E6 proteins of two beta-human papillomaviruses (HPV14 and HPV21) associated with epidermodysplasia verruciformis also interacted with FOXK1/K2 through a motif similar to that of E1A. The E1A mutants deficient in interaction with FOXK1/K2 induced enhanced cell proliferation and oncogenic transformation. The hypertransforming activity of the mutant E1A was suppressed by HPV21 E6. An E1A-E6 chimeric protein containing the Ser/Thr domain of the E6 protein in E1A interacted efficiently with FOXK1/K2 and inhibited cell transformation. Our results suggest that targeting FOXK1/K2 may be a common mechanism for certain beta-HPVs and Adv5. E1A exon 2 mutants deficient in interaction with the dual-specificity kinases DYRK1A/1B and their cofactor HAN11 also induced increased cell proliferation and transformation. Our results suggest that the E1A C-terminal region may suppress cell proliferation and oncogenic transformation through interaction with three different cellular protein complexes: FOXK1/K2, DYRK(1A/1B)/HAN11, and CtBP1/2.

78 FR 42530 - Prospective Grant of an Exclusive License: Human Papillomavirus 16 E2 and E6 Peptides for...

Science.gov (United States)

2013-07-16

... peptide from HPV 16. E6 peptide vaccines are potentially prophylactic or therapeutic for cervical cancer... Exclusive License: Human Papillomavirus 16 E2 and E6 Peptides for Cervical Cancer Vaccine Development AGENCY... principal place of business in Augusta, Georgia. The United States of America is an assignee to the patent...

Rare human papillomavirus 16 E6 variants reveal significant oncogenic potential

Directory of Open Access Journals (Sweden)

Tommasino Massimo

2011-06-01

Full Text Available Abstract The aim of this study was to determine whether low prevalence human papillomavirus (HPV 16 E6 variants differ from high prevalence types in their functional abilities. We evaluated functions relevant to carcinogenesis for the rarely-detected European variants R8Q, R10G and R48W as compared to the commonly detected L83V. Human immortalized keratinocytes (NIKS stably transduced with the E6 variants were used in most functional assays. Low and high prevalence E6 variants displayed similar abilities in abrogation of growth arrest and inhibition of p53 elevation induced by actinomycin D. Differences were detected in the abilities to dysregulate stratification and differentiation of NIKS in organotypic raft cultures, modulate detachment induced apoptosis (anoikis and hyperactivate Wnt signaling. No distinctive phenotype could be assigned to include all rare variants. Like L83V, raft cultures derived from variants R10G and R48W similarly induced hyperplasia and aberrantly expressed keratin 5 in the suprabasal compartment with significantly lower expression of keratin 10. Unlike L83V, both variants, and particularly R48W, induced increased levels of anoikis upon suspension in semisolid medium. R8Q induced a unique phenotype characterized by thin organotypic raft cultures, low expression of keratin 10, and high expression of keratins 5 and 14 throughout all raft layers. Interestingly, in a reporter based assay R8Q exhibited a higher ability to augment TCF/β-catenin transcription. The data suggests that differences in E6 variant prevalence in cervical carcinoma may not be related to the carcinogenic potential of the E6 protein.

Evidence for alteration of EZH2, BMI1, and KDM6A and epigenetic reprogramming in human papillomavirus type 16 E6/E7-expressing keratinocytes.

Science.gov (United States)

Hyland, Paula L; McDade, Simon S; McCloskey, Rachel; Dickson, Glenda J; Arthur, Ken; McCance, Dennis J; Patel, Daksha

2011-11-01

A number of epigenetic alterations occur in both the virus and host cellular genomes during human papillomavirus (HPV)-associated carcinogenesis, and investigations of such alterations, including changes in chromatin proteins and histone modifications, have the potential to lead to therapeutic epigenetic reversion. We report here that transformed HPV16 E6/E7-expressing primary human foreskin keratinocytes (HFKs) (E6/E7 cells) demonstrate increased expression of the PRC2 methyltransferase EZH2 at both the mRNA and protein levels but do not exhibit the expected increase in trimethylated H3K27 (H3K27me3) compared to normal keratinocytes. In contrast, these cells show a reduction in global H3K27me3 levels in vitro, as well as upregulation of the KDM6A demethylase. We further show for the first time that transformation with the HPV16 E6 and E7 oncogenes also results in an increase in phosphorylated EZH2 serine 21 (P-EZH2-Ser21), mediated by active Akt, and in a downregulation of the PRC1 protein BMI1 in these cells. High-grade squamous cervical intraepithelial lesions also showed a loss of H3K27me3 in the presence of increased expression of EZH2. Correlating with the loss of H3K27me3, E6/E7 cells exhibited derepression of specific EZH2-, KMD6A-, and BMI1-targeted HOX genes. These results suggest that the observed reduction in H3K27me3 may be due to a combination of reduced activities/levels of specific polycomb proteins and increases in demethylases. The dysregulation of multiple chromatin proteins resulting in the loss of global H3K27me3 and the transcriptional reprogramming in HPV16 E6/E7-infected cells could provide an epigenetic signature associated with risk and/or progression of HPV16-associated cancers, as well as the potential for epigenetic reversion in the future.

Modulation of DNA methylation by human papillomavirus E6 and E7 oncoproteins in cervical cancer

Science.gov (United States)

Sen, Prakriti; Ganguly, Pooja; Ganguly, Niladri

2018-01-01

Human papillomaviruses (HPVs) are double stranded circular DNA viruses that infect cutaneous and mucosal epithelial cells. Almost 99% of cervical cancer has a HPV infection. The early oncoproteins E6 and E7 are important in this cellular transformation process. Epigenetic mechanisms have long been known to result in decisive alterations in DNA, leading to alterations in DNA-protein interactions, alterations in chromatin structure and compaction and significant alterations in gene expression. The enzymes responsible for these epigenetic modifications are DNA methyl transferases (DNMTs), histone acetylases and deacetylases. Epigenetics has an important role in cancer development by modifying the cellular micro environment. In this review, the authors discuss the role of HPV oncoproteins E6 and E7 in modulating the epigenetic mechanisms inside the host cell. The oncoproteins induce the expression of DNMTs which lead to aberrant DNA methylations and disruption of the normal epigenetic processes. The E7 oncoprotein may additionally directly bind and induce methyl transferase activity of the enzyme. These modulations lead to altered gene expression levels, particularly the genes involved in apoptosis, cell cycle and cell adhesion. In addition, the present review discusses how epigenetic mechanisms may be targeted for possible therapeutic interventions for HPV mediated cervical cancer. PMID:29285184

Tattoo Delivery of a Semliki Forest Virus-Based Vaccine Encoding Human Papillomavirus E6 and E7

Directory of Open Access Journals (Sweden)

Stephanie van de Wall

2015-03-01

Full Text Available The skin is an attractive organ for immunization because of the presence of antigen-presenting cells. Intradermal delivery via tattooing has demonstrated superior vaccine immunogenicity of DNA vaccines in comparison to conventional delivery methods. In this study, we explored the efficacy of tattoo injection of a tumor vaccine based on recombinant Semliki Forest virus replicon particles (rSFV targeting human papillomavirus (HPV. Tattoo injection of rSFV particles resulted in antigen expression in both the skin and draining lymph nodes. In comparison with intramuscular injection, the overall antigen expression determined at the site of administration and draining lymph nodes was 10-fold lower upon tattoo injection. Delivery of SFV particles encoding the E6 and E7 antigens of human papillomavirus type 16 (SFVeE6,7 via tattooing resulted in HPV-specific cytotoxic T cells and in vivo therapeutic antitumor response. Strikingly, despite the observed lower overall transgene expression, SFVeE6,7 delivered via tattoo injection resulted in higher or equal levels of immune responses as compared to intramuscular injection. The intrinsic immunogenic potential of tattooing provides a benefit for immunotherapy based on an alphavirus.

Tattoo Delivery of a Semliki Forest Virus-Based Vaccine Encoding Human Papillomavirus E6 and E7

Science.gov (United States)

van de Wall, Stephanie; Walczak, Mateusz; van Rooij, Nienke; Hoogeboom, Baukje-Nynke; Meijerhof, Tjarko; Nijman, Hans W.; Daemen, Toos

2015-01-01

The skin is an attractive organ for immunization because of the presence of antigen-presenting cells. Intradermal delivery via tattooing has demonstrated superior vaccine immunogenicity of DNA vaccines in comparison to conventional delivery methods. In this study, we explored the efficacy of tattoo injection of a tumor vaccine based on recombinant Semliki Forest virus replicon particles (rSFV) targeting human papillomavirus (HPV). Tattoo injection of rSFV particles resulted in antigen expression in both the skin and draining lymph nodes. In comparison with intramuscular injection, the overall antigen expression determined at the site of administration and draining lymph nodes was 10-fold lower upon tattoo injection. Delivery of SFV particles encoding the E6 and E7 antigens of human papillomavirus type 16 (SFVeE6,7) via tattooing resulted in HPV-specific cytotoxic T cells and in vivo therapeutic antitumor response. Strikingly, despite the observed lower overall transgene expression, SFVeE6,7 delivered via tattoo injection resulted in higher or equal levels of immune responses as compared to intramuscular injection. The intrinsic immunogenic potential of tattooing provides a benefit for immunotherapy based on an alphavirus. PMID:26343186

Regulation of the Wnt/β-Catenin Signaling Pathway by Human Papillomavirus E6 and E7 Oncoproteins

Directory of Open Access Journals (Sweden)

Jesus Omar Muñoz Bello

2015-08-01

Full Text Available Cell signaling pathways are the mechanisms by which cells transduce external stimuli, which control the transcription of genes, to regulate diverse biological effects. In cancer, distinct signaling pathways, such as the Wnt/β-catenin pathway, have been implicated in the deregulation of critical molecular processes that affect cell proliferation and differentiation. For example, changes in β-catenin localization have been identified in Human Papillomavirus (HPV-related cancers as the lesion progresses. Specifically, β-catenin relocates from the membrane/cytoplasm to the nucleus, suggesting that this transcription regulator participates in cervical carcinogenesis. The E6 and E7 oncoproteins are responsible for the transforming activity of HPV, and some studies have implicated these viral oncoproteins in the regulation of the Wnt/β-catenin pathway. Nevertheless, new interactions of HPV oncoproteins with cellular proteins are emerging, and the study of the biological effects of such interactions will help to understand HPV-related carcinogenesis. Viruses 2015, 7 4735 This review addresses the accumulated evidence of the involvement of the HPV E6 and E7 oncoproteins in the activation of the Wnt/β-catenin pathway.

Evidence for Alteration of EZH2, BMI1, and KDM6A and Epigenetic Reprogramming in Human Papillomavirus Type 16 E6/E7-Expressing Keratinocytes ▿

Science.gov (United States)

Hyland, Paula L.; McDade, Simon S.; McCloskey, Rachel; Dickson, Glenda J.; Arthur, Ken; McCance, Dennis J.; Patel, Daksha

2011-01-01

A number of epigenetic alterations occur in both the virus and host cellular genomes during human papillomavirus (HPV)-associated carcinogenesis, and investigations of such alterations, including changes in chromatin proteins and histone modifications, have the potential to lead to therapeutic epigenetic reversion. We report here that transformed HPV16 E6/E7-expressing primary human foreskin keratinocytes (HFKs) (E6/E7 cells) demonstrate increased expression of the PRC2 methyltransferase EZH2 at both the mRNA and protein levels but do not exhibit the expected increase in trimethylated H3K27 (H3K27me3) compared to normal keratinocytes. In contrast, these cells show a reduction in global H3K27me3 levels in vitro, as well as upregulation of the KDM6A demethylase. We further show for the first time that transformation with the HPV16 E6 and E7 oncogenes also results in an increase in phosphorylated EZH2 serine 21 (P-EZH2-Ser21), mediated by active Akt, and in a downregulation of the PRC1 protein BMI1 in these cells. High-grade squamous cervical intraepithelial lesions also showed a loss of H3K27me3 in the presence of increased expression of EZH2. Correlating with the loss of H3K27me3, E6/E7 cells exhibited derepression of specific EZH2-, KMD6A-, and BMI1-targeted HOX genes. These results suggest that the observed reduction in H3K27me3 may be due to a combination of reduced activities/levels of specific polycomb proteins and increases in demethylases. The dysregulation of multiple chromatin proteins resulting in the loss of global H3K27me3 and the transcriptional reprogramming in HPV16 E6/E7-infected cells could provide an epigenetic signature associated with risk and/or progression of HPV16-associated cancers, as well as the potential for epigenetic reversion in the future. PMID:21865393

Human papillomavirus 16E6 and NFX1-123 potentiate notch signaling and differentiation without activating cellular arrest

Energy Technology Data Exchange (ETDEWEB)

Vliet-Gregg, Portia A.; Hamilton, Jennifer R. [Center for Global Infectious Disease Research, Seattle Children' s Research Institute, 1900 Ninth Ave., Seattle, WA 98101 (United States); Katzenellenbogen, Rachel A., E-mail: rkatzen@uw.edu [Center for Global Infectious Disease Research, Seattle Children' s Research Institute, 1900 Ninth Ave., Seattle, WA 98101 (United States); Department of Pediatrics, Division of Adolescent Medicine, University of Washington, Seattle WA (United States)

2015-04-15

High-risk human papillomavirus (HR HPV) oncoproteins bind host cell proteins to dysregulate and uncouple apoptosis, senescence, differentiation, and growth. These pathways are important for both the viral life cycle and cancer development. HR HPV16 E6 (16E6) interacts with the cellular protein NFX1-123, and they collaboratively increase the growth and differentiation master regulator, Notch1. In 16E6 expressing keratinocytes (16E6 HFKs), the Notch canonical pathway genes Hes1 and Hes5 were increased with overexpression of NFX1-123, and their expression was directly linked to the activation or blockade of the Notch1 receptor. Keratinocyte differentiation genes Keratin 1 and Keratin 10 were also increased, but in contrast their upregulation was only indirectly associated with Notch1 receptor stimulation and was fully unlinked to growth arrest, increased p21{sup Waf1/CIP1}, or decreased proliferative factor Ki67. This leads to a model of 16E6, NFX1-123, and Notch1 differently regulating canonical and differentiation pathways and entirely uncoupling cellular arrest from increased differentiation. - Highlights: • 16E6 and NFX1-123 increased the Notch canonical pathway through Notch1. • 16E6 and NFX1-123 increased the differentiation pathway indirectly through Notch1. • 16E6 and NFX1-123 increased differentiation gene expression without growth arrest. • Increased NFX1-123 with 16E6 may create an ideal cellular phenotype for HPV.

ANTIBODIES TO HUMAN PAPILLOMAVIRUS TYPE-16 E7 RELATED TO CLINICOPATHOLOGICAL DATA IN PATIENTS WITH CERVICAL-CARCINOMA

NARCIS (Netherlands)

BAAY, MFD; DUK, JM; BURGER, MPM; WALBOOMERS, J; TERSCHEGGET, J; GROENIER, KH; DEBRUIJN, HWA; STOLZ, E; HERBRINK, P

Aims-To investigate the correlation between antibodies to the transforming protein E7 of human papillomavirus (HPV) type 16 and clinicopathological indices in women with cervical squamous carcinoma. Methods-A synthetic peptide of the HPV type 16 E7 protein (amino acids 6 to 35) was used to screen

Immortalization of normal human embryonic fibroblasts by introduction of either the human papillomavirus type 16 E6 or E7 gene alone.

Science.gov (United States)

Yamamoto, Akito; Kumakura, Shin-ichi; Uchida, Minoru; Barrett, J Carl; Tsutsui, Takeki

2003-09-01

The ability of the human papillomavirus type 16 (HPV-16) E6 or E7 gene to induce immortalization of normal human embryonic fibroblast WHE-7 cells was examined. WHE-7 cells at 9 population doublings (PD) were infected with retrovirus vectors encoding either HPV-16 E6 or E7 alone or both E6 and E7 (E6/E7). One of 4 isolated clones carrying E6 alone became immortal and is currently at >445 PD. Four of 4 isolated clones carrying E7 alone escaped from crisis and are currently at >330 PD. Three of 5 isolated clones carrying E6/E7 were also immortalized and are currently at >268 PD. The immortal clone carrying E6 only and 2 of the 3 immortal clones carrying E6/E7 expressed a high level of E6 protein, and all the immortal clones carrying E7 alone and the other immortal clone carrying E6/E7 expressed a high level of E7 protein when compared to their mortal or precrisis clones. The immortal clones expressing a high level of E6 or E7 protein were positive for telomerase activity or an alternative mechanism of telomere maintenance, respectively, known as ALT (alternative lengthening of telomeres). All the mortal or precrisis clones were negative for both phenotypes. All the immortal clones exhibited abrogation of G1 arrest after DNA damage by X-ray irradiation. The expression of INK4a protein (p16(INK4a)) was undetectable in the E6-infected mortal and immortal clones, whereas Rb protein (pRb) was hyperphosphorylated only in the immortal clone. The p16(INK4a) protein was overexpressed in all the E7-infected immortal clones and their clones in the pre-crisis period as well as all the E6/E7-infected mortal and immortal clones, but the pRb expression was downregulated in all of these clones. These results demonstrate for the first time to our knowledge that HPV-16 E6 or E7 alone can induce immortalization of normal human embryonic fibroblasts. Inactivation of p16(INK4a)/pRb pathways in combination with activation of a telomere maintenance mechanism is suggested to be necessary for

E6 and E7 Gene Polymorphisms in Human Papillomavirus Types-58 and 33 Identified in Southwest China.

Directory of Open Access Journals (Sweden)

Zuyi Chen

Full Text Available Cancer of the cervix is associated with infection by certain types of human papillomavirus (HPV. The gene variants differ in immune responses and oncogenic potential. The E6 and E7 proteins encoded by high-risk HPV play a key role in cellular transformation. HPV-33 and HPV-58 types are highly prevalent among Chinese women. To study the gene intratypic variations, polymorphisms and positive selections of HPV-33 and HPV-58 E6/E7 in southwest China, HPV-33 (E6, E7: n = 216 and HPV-58 (E6, E7: n = 405 E6 and E7 genes were sequenced and compared to others submitted to GenBank. Phylogenetic trees were constructed by Maximum-likelihood and the Kimura 2-parameters methods by MEGA 6 (Molecular Evolutionary Genetics Analysis version 6.0. The diversity of secondary structure was analyzed by PSIPred software. The selection pressures acting on the E6/E7 genes were estimated by PAML 4.8 (Phylogenetic Analyses by Maximun Likelihood version4.8 software. The positive sites of HPV-33 and HPV-58 E6/E7 were contrasted by ClustalX 2.1. Among 216 HPV-33 E6 sequences, 8 single nucleotide mutations were observed with 6/8 non-synonymous and 2/8 synonymous mutations. The 216 HPV-33 E7 sequences showed 3 single nucleotide mutations that were non-synonymous. The 405 HPV-58 E6 sequences revealed 8 single nucleotide mutations with 4/8 non-synonymous and 4/8 synonymous mutations. Among 405 HPV-58 E7 sequences, 13 single nucleotide mutations were observed with 10/13 non-synonymous mutations and 3/13 synonymous mutations. The selective pressure analysis showed that all HPV-33 and 4/6 HPV-58 E6/E7 major non-synonymous mutations were sites of positive selection. All variations were observed in sites belonging to major histocompatibility complex and/or B-cell predicted epitopes. K93N and R145 (I/N were observed in both HPV-33 and HPV-58 E6.

The Human Papillomavirus Type 16 E6 Gene Alone Is Sufficient To Induce Carcinomas in Transgenic Animals

Science.gov (United States)

Song, Shiyu; Pitot, Henry C.; Lambert, Paul F.

1999-01-01

High-risk human papillomaviruses (HPVs) are the causative agents of certain human cancers. HPV type 16 (HPV16) is the papillomavirus most frequently associated with cervical cancer in women. The E6 and E7 genes of HPV are expressed in cells derived from these cancers and can transform cells in tissue culture. Animal experiments have demonstrated that E6 and E7 together cause tumors. We showed previously that E6 and E7 together or E7 alone could induce skin tumors in mice when these genes were expressed in the basal epithelia of the skin. In this study, we investigated the role that the E6 gene plays in carcinogenesis. We generated K14E6 transgenic mice, in which the HPV16 E6 gene was directed in its expression by the human keratin 14 promoter (hK14) to the basal layer of the epidermis. We found that E6 induced cellular hyperproliferation and epidermal hyperplasia and caused skin tumors in adult mice. Interestingly, the tumors derived from E6 were mostly malignant, as opposed to the tumors from E7 mice, which were mostly benign. This result leads us to hypothesize that E6 may contribute differently than E7 to HPV-associated carcinogenesis; whereas E7 primarily contributes to the early stages of carcinogenesis that lead to the formation of benign tumors, E6 primarily contributes to the late stages of carcinogenesis that lead to malignancy. PMID:10364340

A high-throughput cellular assay to quantify the p53-degradation activity of E6 from different human papillomavirus types.

Science.gov (United States)

Gagnon, David; Archambault, Jacques

2015-01-01

A subset of human papillomaviruses (HPVs), known as the high-risk types, are the causative agents of cervical cancer and other malignancies of the anogenital region and oral mucosa. The capacity of these viruses to induce cancer and to immortalize cells in culture relies in part on a critical function of their E6 oncoprotein, that of promoting the poly-ubiquitination of the cellular tumor suppressor protein p53 and its subsequent degradation by the proteasome. Here, we describe a cellular assay to measure the p53-degradation activity of E6 from different HPV types. This assay is based on a translational fusion of p53 to Renilla luciferase (Rluc-p53) that remains sensitive to degradation by high-risk E6 and whose steady-state levels can be accurately measured in standard luciferase assays. The p53-degradation activity of any E6 protein can be tested and quantified in transiently transfected cells by determining the amount of E6-expression vector required to reduce by half the levels of RLuc-p53 luciferase activity (50 % effective concentration [EC50]). The high-throughput and quantitative nature of this assay makes it particularly useful to compare the p53-degradation activities of E6 from several HPV types in parallel.

Transforming properties of Felis catus papillomavirus type 2 E6 and E7 putative oncogenes in vitro and their transcriptional activity in feline squamous cell carcinoma in vivo

Energy Technology Data Exchange (ETDEWEB)

Altamura, Gennaro, E-mail: gennaro.altamura@unina.it [Department of Veterinary Medicine and Animal Productions, General Pathology and Pathological Anatomy Unit, University of Naples Federico II, Via Delpino 1, 80137 Naples (Italy); Corteggio, Annunziata, E-mail: ancorteg@unina.it [Department of Veterinary Medicine and Animal Productions, General Pathology and Pathological Anatomy Unit, University of Naples Federico II, Via Delpino 1, 80137 Naples (Italy); Pacini, Laura, E-mail: PaciniL@students.iarc.fr [Infections and Cancer Biology Group, International Agency for Research on Cancer, 150 Cours Albert Thomas, 69372 Lyon (France); Conte, Andrea, E-mail: andreaconte88@hotmail.it [Department of Molecular Medicine and Medical Biotechnologies, University of Naples Federico II, Via Pansini 5, 80131 Naples (Italy); Pierantoni, Giovanna Maria, E-mail: gmpieran@unina.it [Department of Molecular Medicine and Medical Biotechnologies, University of Naples Federico II, Via Pansini 5, 80131 Naples (Italy); Tommasino, Massimo, E-mail: tommasinom@iarc.fr [Infections and Cancer Biology Group, International Agency for Research on Cancer, 150 Cours Albert Thomas, 69372 Lyon (France); Accardi, Rosita, E-mail: accardir@iarc.fr [Infections and Cancer Biology Group, International Agency for Research on Cancer, 150 Cours Albert Thomas, 69372 Lyon (France); Borzacchiello, Giuseppe, E-mail: borzacch@unina.it [Department of Veterinary Medicine and Animal Productions, General Pathology and Pathological Anatomy Unit, University of Naples Federico II, Via Delpino 1, 80137 Naples (Italy)

2016-09-15

Felis catus papillomavirus type 2 (FcaPV2) DNA is found in feline cutaneous squamous cell carcinomas (SCCs); however, its biological properties are still uncharacterized. In this study, we successfully expressed FcaPV2 E6 and E7 putative oncogenes in feline epithelial cells and demonstrated that FcaPV2 E6 binds to p53, impairing its protein level. In addition, E6 and E7 inhibited ultraviolet B (UVB)-triggered accumulation of p53, p21 and pro-apoptotic markers such as Cleaved Caspase3, Bax and Bak, suggesting a synergistic action of the virus with UV exposure in tumour pathogenesis. Furthermore, FcaPV2 E7 bound to feline pRb and impaired pRb levels, resulting in upregulation of the downstream pro-proliferative genes Cyclin A and Cdc2. Importantly, we demonstrated mRNA expression of FcaPV2 E2, E6 and E7 in feline SCC samples, strengthening the hypothesis of a causative role in the development of feline SCC. - Highlights: • FcaPV2 E6 binds to and deregulates feline p53 protein. • FcaPV2 E7 binds to and deregulates feline pRb protein. • FcaPV2 oncogenes inhibit UVB-induced apoptosis. • FcaPV2 E6E7 and E7 increase the lifespan of primary cells. • FcaPV2 E2, E6 and E7 are expressed at the mRNA level in feline SCC in vivo.

Human papillomavirus E6 and E7 oncoproteins as risk factors

Indian Academy of Sciences (India)

Prakash

J. Biosci. 34(1), March 2009. 1. Introduction. Human papillomavirus (HPV) is a double-stranded DNA virus that ..... contact and loss of cell polarity (Watson et al 2003; Thomas ..... Arrand JR 1995 Translation of the human papillomavirus type 16.

Genetic immunization against cervical carcinoma : induction of cytotoxic T lymphocyte activity with a recombinant alphavirus vector expressing human papillomavirus type 16 E6 and E7

NARCIS (Netherlands)

Daemen, T; Pries, F; Bungener, L; Kraak, M; Regts, J; Wilschut, J

infection of genital epithelial cells with human papillomavirus (HPV) types 16 and 18 is closely associated with the development of cervical carcinoma. The transforming potential of these high-risk HPVs depends on the expression of the E6 and E7 early viral gene products. Since the expression of E6

Sonoporation delivery of monoclonal antibodies against human papillomavirus 16 E6 restores p53 expression in transformed cervical keratinocytes.

Directory of Open Access Journals (Sweden)

Melissa Togtema

Full Text Available High-risk types of human papillomavirus (HPV, such as HPV16, have been found in nearly all cases of cervical cancer. Therapies targeted at blocking the HPV16 E6 protein and its deleterious effects on the tumour suppressor pathways of the cell can reverse the malignant phenotype of affected keratinocytes while sparing uninfected cells. Through a strong interdisciplinary collaboration between engineering and biology, a novel, non-invasive intracellular delivery method for the HPV16 E6 antibody, F127-6G6, was developed. The method employs high intensity focused ultrasound (HIFU in combination with microbubbles, in a process known as sonoporation. In this proof of principle study, it was first demonstrated that sonoporation antibody delivery into the HPV16 positive cervical carcinoma derived cell lines CaSki and SiHa was possible, using chemical transfection as a baseline for comparison. Delivery of the E6 antibody using sonoporation significantly restored p53 expression in these cells, indicating the antibody is able to enter the cells and remains active. This delivery method is targeted, non-cytotoxic, and non-invasive, making it more easily translatable for in vivo experiments than other transfection methods.

The E5 Proteins

OpenAIRE

DiMaio, Daniel; Petti, Lisa

2013-01-01

The E5 proteins are short transmembrane proteins encoded by many animal and human papillomaviruses. These proteins display transforming activity in cultured cells and animals, and they presumably also play a role in the productive virus life cycle. The E5 proteins are thought to act by modulating the activity of cellular proteins. Here, we describe the biological activities of the best-studied E5 proteins and discuss the evidence implicating specific protein targets and pathways in mediating ...

The Cellular DNA Helicase ChlR1 Regulates Chromatin and Nuclear Matrix Attachment of the Human Papillomavirus 16 E2 Protein and High-Copy-Number Viral Genome Establishment.

Science.gov (United States)

Harris, Leanne; McFarlane-Majeed, Laura; Campos-León, Karen; Roberts, Sally; Parish, Joanna L

2017-01-01

In papillomavirus infections, the viral genome is established as a double-stranded DNA episome. To segregate the episomes into daughter cells during mitosis, they are tethered to cellular chromatin by the viral E2 protein. We previously demonstrated that the E2 proteins of diverse papillomavirus types, including bovine papillomavirus (BPV) and human papillomavirus 16 (HPV16), associate with the cellular DNA helicase ChlR1. This virus-host interaction is important for the tethering of BPV E2 to mitotic chromatin and the stable maintenance of BPV episomes. The role of the association between E2 and ChlR1 in the HPV16 life cycle is unresolved. Here we show that an HPV16 E2 Y131A mutant (E2 Y131A ) had significantly reduced binding to ChlR1 but retained transcriptional activation and viral origin-dependent replication functions. Subcellular fractionation of keratinocytes expressing E2 Y131A showed a marked change in the localization of the protein. Compared to that of wild-type E2 (E2 WT ), the chromatin-bound pool of E2 Y131A was decreased, concomitant with an increase in nuclear matrix-associated protein. Cell cycle synchronization indicated that the shift in subcellular localization of E2 Y131A occurred in mid-S phase. A similar alteration between the subcellular pools of the E2 WT protein occurred upon ChlR1 silencing. Notably, in an HPV16 life cycle model in primary human keratinocytes, mutant E2 Y131A genomes were established as episomes, but at a markedly lower copy number than that of wild-type HPV16 genomes, and they were not maintained upon cell passage. Our studies indicate that ChlR1 is an important regulator of the chromatin association of E2 and of the establishment and maintenance of HPV16 episomes. Infections with high-risk human papillomaviruses (HPVs) are a major cause of anogenital and oropharyngeal cancers. During infection, the circular DNA genome of HPV persists within the nucleus, independently of the host cell chromatin. Persistence of infection

Human papillomavirus (HPV) type 16 E7 protein bodies cause tumour regression in mice

International Nuclear Information System (INIS)

Whitehead, Mark; Öhlschläger, Peter; Almajhdi, Fahad N; Alloza, Leonor; Marzábal, Pablo; Meyers, Ann E; Hitzeroth, Inga I; Rybicki, Edward P

2014-01-01

Human papillomaviruses (HPV) are the causative agents of cervical cancer in women, which results in over 250 000 deaths per year. Presently there are two prophylactic vaccines on the market, protecting against the two most common high-risk HPV types 16 and 18. These vaccines remain very expensive and are not generally affordable in developing countries where they are needed most. Additionally, there remains a need to treat women that are already infected with HPV, and who have high-grade lesions or cervical cancer. In this paper, we characterize the immunogenicity of a therapeutic vaccine that targets the E7 protein of the most prevalent high-risk HPV - type 16 – the gene which has previously been shown to be effective in DNA vaccine trials in mice. The synthetic shuffled HPV-16 E7 (16E7SH) has lost its transforming properties but retains all naturally-occurring CTL epitopes. This was genetically fused to Zera®, a self-assembly domain of the maize γ-zein able to induce the accumulation of recombinant proteins into protein bodies (PBs), within the endoplasmic reticulum in a number of expression systems. High-level expression of the HPV 16E7SH protein fused to Zera® in plants was achieved, and the protein bodies could be easily and cost-effectively purified. Immune responses comparable to the 16E7SH DNA vaccine were demonstrated in the murine model, with the protein vaccine successfully inducing a specific humoral as well as cell mediated immune response, and mediating tumour regression. The fusion of 16E7SH to the Zera® peptide was found to enhance the immune responses, presumably by means of a more efficient antigen presentation via the protein bodies. Interestingly, simply mixing the free PBs and 16E7SH also enhanced immune responses, indicating an adjuvant activity for the Zera® PBs

Detection of human papillomavirus type 18 E6 and E7-specific CD4+ T-helper 1 immunity in relation to health versus disease

NARCIS (Netherlands)

Welters, Marij J. P.; van der Logt, Pauline; van den Eeden, Susan J. F.; Kwappenberg, Kitty M. C.; Drijfhout, Jan Wouter; Fleuren, Gert Jan; Kenter, Gemma G.; Melief, Cornelis J. M.; van der Burg, Sjoerd H.; Offringa, Rienk

2006-01-01

The most common high-risk human papillomavirus types, HPV16 and 18, differ markedly with respect to their interaction with the host. Clearance of HPV18 infections generally takes longer and HPV18-positive cancers have a poorer prognosis. We therefore evaluated Th1-type immunity against the E6 and E7

Molecular screening of compounds to the predicted Protein-Protein Interaction site of Rb1-E7 with p53- E6 in HPV

Science.gov (United States)

Shaikh, Faraz; Sanehi, Parvish; Rawal, Rakesh

2012-01-01

Cervical cancer is malignant neoplasm of the cervix uteri or cervical area. Human Papillomaviruses (HPVs) which are heterogeneous groups of small double stranded DNA viruses are considered as the primary cause of cervical cancer, involved in 90% of all Cervical Cancers. Two early HPV genes, E6 and E7, are known to play crucial role in tumor formation. E6 binds with p53 and prevents its translocation and thereby inhibit the ability of p53 to activate or repress target genes. E7 binds to hypophosphorylated Rb and thereby induces cells to enter into premature S-phase by disrupting Rb-E2F complexes. The strategy of the research work was to target the site of interaction of Rb1 -E7 & p53-E6. A total of 88 compounds were selected for molecular screening, based on comprehensive literature survey for natural compounds with anti-cancer activity. Molecular docking analysis was carried out with Molegro Virtual Docker, to screen the 88 chosen compounds and rank them according to their binding affinity towards the site of interaction of the viral oncoproteins and human tumor suppressor proteins. The docking result revealed that Nicandrenone a member of Withanolides family of chemical compounds as the most likely molecule that can be used as a candidate drug against HPV induced cervical cancer. Abbreviations HPV - Human Papiloma Virus, HTSP - Human Tumor Suppressor Proteins, VOP - Viral oncoproteins. PMID:22829740

Human Papillomavirus Type 16 E6 and E7 Oncoproteins Act Synergistically to Cause Head and Neck Cancer in Mice

Science.gov (United States)

Jabbar, Sean; Strati, Katerina; Shin, Myeong Kyun; Pitot, Henry C.; Lambert, Paul F.

2010-01-01

High-risk human papillomaviruses (HPVs) contribute to cervical and other anogenital cancers, and they are also linked etiologically to a subset of head and neck squamous cell carcinomas (HNSCC). We previously established a model for HPV-associated HNSCC in which we treated transgenic mice expressing the papillomaviral oncoproteins with the chemical carcinogen 4-nitroquinoline-1-oxide (4-NQO). We found that the HPV-16 E7 oncoprotein was highly potent in causing HNSCC, and its dominance masked any potential oncogenic contribution of E6, a second papillomaviral oncoprotein commonly expressed in human cancers. In the current study, we shortened the duration of treatment with 4-NQO to reduce the incidence of cancers and discovered a striking synergy between E6 and E7 in causing HNSCC. Comparing the oncogenic properties of wild-type versus mutant E6 genes in this model for HNSCC uncovered a role for some but not other cellular targets of E6 previously shown to contribute to cervical cancer. PMID:20797753

Rat primary embryo fibroblast cells suppress transformation by the E6 and E7 genes of human papillomavirus type 16 in somatic hybrid cells.

OpenAIRE

Miyasaka, M; Takami, Y; Inoue, H; Hakura, A

1991-01-01

The E6 and E7 genes of human papillomavirus type 16 (HPV-16) transform established lines of rat cells but not rat cells in primary culture irrespective of the expression of the two genes. The reason for this difference between the susceptibilities of cell lines and primary cells was examined by using hybrid cells obtained by somatic cell fusion of rat cell lines transformed by the E6 and E7 genes of HPV-16 and freshly isolated rat embryo fibroblast cells. In these hybrid cells, transformed ph...

Characterization of the North American beaver (Castor canadensis) papillomavirus genome.

Science.gov (United States)

Rogovskyy, Artem S; Chen, Zigui; Burk, Robert D; Bankhead, Troy

2014-01-10

The papillomaviruses comprise a large group of viruses that cause proliferations of the stratified squamous epithelium of skin and mucosa in a variety of animals. An earlier report identified a novel papillomavirus of the North American beaver, Castor canadensis (CcanPV1) that was associated with cutaneous exophytic lesions. In the current study, we determined the sequence of the complete 7435 basepair genome of CcanPV1. The genome contains an Upstream Regulatory Region located between the end of L1 and the start of E6, and seven canonical papillomavirus open reading frames encoding five early (E6, E7, E1, E2, and E4) and two late (L2 and L1) proteins. No E5 open reading frame was detected. Phylogenetic analysis of the CcanPV1 genome places the virus between the genera Kappapapillomavirus and Mupapillomavirus. Analyses of the papillomavirus genomes detected in different species of the order Rodentia indicate these viruses do not form a monophyletic clade. Copyright © 2013 Elsevier B.V. All rights reserved.

Human papillomavirus E5 oncoproteins bind the A4 endoplasmic reticulum protein to regulate proliferative ability upon differentiation

Energy Technology Data Exchange (ETDEWEB)

Kotnik Halavaty, Katarina; Regan, Jennifer; Mehta, Kavi; Laimins, Laimonis, E-mail: l-laimins@northwestern.edu

2014-03-15

Human papillomaviruses (HPV) infect stratified epithelia and link their life cycles to epithelial differentiation. The HPV E5 protein plays a role in the productive phase of the HPV life cycle but its mechanism of action is still unclear. We identify a new binding partner of E5, A4, using a membrane-associated yeast-two hybrid system. The A4 protein co-localizes with HPV 31 E5 in perinuclear regions and forms complexes with E5 and Bap31. In normal keratinocytes, A4 is found primarily in basal cells while in HPV positive cells high levels of A4 are seen in both undifferentiated and differentiated cells. Reduction of A4 expression by shRNAs, enhanced HPV genome amplification and increased cell proliferation ability following differentiation but this was not seen in cells lacking E5. Our studies suggest that the A4 protein is an important E5 binding partner that plays a role in regulating cell proliferation ability upon differentiation. - Highlights: • A4 associates with HPV 31 E5 proteins. • A4 is localized to endoplasmic reticulum. • HPV proteins induce A4 expression in suprabasal layers of stratified epithelium. • E5 is important for proliferation ability of differentiating HPV positive cells.

Molecular Docking Explains Atomic Interaction between Plant-originated Ligands and Oncogenic E7 Protein of High Risk Human Papillomavirus Type 16

Directory of Open Access Journals (Sweden)

Satish Kumar

2014-12-01

Full Text Available Cervical cancer caused by Human papillomavirus (HPV is one of the leading causes of cancer mortality in women worldwide, particularly in the developing countries. In the last few decades, various compounds from plant origin such as Curcumin, Epigallocatechin gallate (EGCG, Jaceosidin, Resveratrol etc. have been used as anti cancer therapeutic agents. Different studies have shown these plant-originated compounds are able to suppress HPV infection. The E6 and E7 oncoproteins of high-risk HPV play a key role in HPV related cancers. In this study, we explored these ligands from plants origin against E7 oncoprotein of high risk HPV 16, which is known to inactivate tumor suppressor pRb protein. A robust homology model of HPV 16 E7 was built to foresee the interaction mechanism of E7 oncoprotein with these ligands using structure-based drug designing approach. Docking studies demonstrate the interaction of these ligands with pRb binding site of E7 protein by residues Tyr52, Asn53, Val55, Phe57, Cys59, Ser63, Thr64, Thr72, Arg77, Glu80 and Asp81 and help restoration of pRb functioning. This in silico based atomic interaction between these ligands and E7 protein may assist in validating the plant-originated ligands as effective drugs against HPV.

Human papillomavirus 16 E5 induces bi-nucleated cell formation by cell-cell fusion

International Nuclear Information System (INIS)

Hu Lulin; Plafker, Kendra; Vorozhko, Valeriya; Zuna, Rosemary E.; Hanigan, Marie H.; Gorbsky, Gary J.; Plafker, Scott M.; Angeletti, Peter C.; Ceresa, Brian P.

2009-01-01

Human papillomaviruses (HPV) 16 is a DNA virus encoding three oncogenes - E5, E6, and E7. The E6 and E7 proteins have well-established roles as inhibitors of tumor suppression, but the contribution of E5 to malignant transformation is controversial. Using spontaneously immortalized human keratinocytes (HaCaT cells), we demonstrate that expression of HPV16 E5 is necessary and sufficient for the formation of bi-nucleated cells, a common characteristic of precancerous cervical lesions. Expression of E5 from non-carcinogenic HPV6b does not produce bi-nucleate cells. Video microscopy and biochemical analyses reveal that bi-nucleates arise through cell-cell fusion. Although most E5-induced bi-nucleates fail to propagate, co-expression of HPV16 E6/E7 enhances the proliferation of these cells. Expression of HPV16 E6/E7 also increases bi-nucleated cell colony formation. These findings identify a new role for HPV16 E5 and support a model in which complementary roles of the HPV16 oncogenes lead to the induction of carcinogenesis

Oral administration of human papillomavirus type 16 E7 displayed on Lactobacillus casei induces E7-specific antitumor effects in C57/BL6 mice.

Science.gov (United States)

Poo, Haryoung; Pyo, Hyun-Mi; Lee, Tae-Young; Yoon, Sun-Woo; Lee, Jong-Soo; Kim, Chul-Joong; Sung, Moon-Hee; Lee, Seung-Hoon

2006-10-01

The mounting of a specific immune response against the human papillomavirus type 16 E7 protein (HPV16 E7) is important for eradication of HPV16 E7-expressing cancer cells from the cervical mucosa. To induce a mucosal immune response by oral delivery of the E7 antigen, we expressed the HPV16 E7 antigen on the surface of Lactobacillus casei by employing a novel display system in which the poly-gamma-glutamic acid (gamma-PGA) synthetase complex A (PgsA) from Bacillus subtilis (chungkookjang) was used as an anchoring motif. After surface expression of the HPV16 E7 protein was confirmed by Western blot, flow cytometry and immunofluorescence microscopy, mice were orally inoculated with L. casei-PgsA-E7. E7-specific serum IgG and mucosal IgA productions were enhanced after oral administration and significantly enhanced after boosting. Systemic and local cellular immunities were significantly increased after boosting, as shown by increased counts of lymphocytes (SI = 9.7 +/- 1.8) and IFN-gamma secreting cells [510 +/- 86 spot-forming cells/10(6)cells] among splenocytes and increased IFN-gamma in supernatants of vaginal lymphocytes. Furthermore, in an E7-based mouse tumor model, animals receiving orally administered L. casei-PgsA-E7 showed reduced tumor size and increased survival rate versus mice receiving control (L. casei-PgsA) immunization. These results collectively indicate that the oral administration of E7 displayed on lactobacillus induces cellular immunity and antitumor effects in mice. Copyright 2006 Wiley-Liss, Inc.

Gene silencing of HPV16 E6/E7 induced by promoter-targeting siRNA in SiHa cells

OpenAIRE

Hong, D; Lu, W; Ye, F; Hu, Y; Xie, X

2009-01-01

Background: Recently, transcriptional gene silencing induced by small interfering RNA (siRNA) was found in mammalian and human cells. However, previous studies focused on endogenous genes. Methods: In this study, we designed siRNA targeting the promoter of human papillomavirus 16 E6/E7 and transfected it into the cervical cancer cell line, SiHa. E6 and E7 mRNA and protein expression were detected in cells treated by promoter-targeting siRNA. Futhermore, cellular growth, proliferation, apoptos...

Human papillomavirus gene expression

International Nuclear Information System (INIS)

Chow, L.T.; Hirochika, H.; Nasseri, M.; Stoler, M.H.; Wolinsky, S.M.; Chin, M.T.; Hirochika, R.; Arvan, D.S.; Broker, T.R.

1987-01-01

To determine the role of tissue differentiation on expression of each of the papillomavirus mRNA species identified by electron microscopy, the authors prepared exon-specific RNA probes that could distinguish the alternatively spliced mRNA species. Radioactively labeled single-stranded RNA probes were generated from a dual promoter vector system and individually hybridized to adjacent serial sections of formalin-fixed, paraffin-embedded biopsies of condylomata. Autoradiography showed that each of the message species had a characteristic tissue distribution and relative abundance. The authors have characterized a portion of the regulatory network of the HPVs by showing that the E2 ORF encodes a trans-acting enhancer-stimulating protein, as it does in BPV-1 (Spalholz et al. 1985). The HPV-11 enhancer was mapped to a 150-bp tract near the 3' end of the URR. Portions of this region are duplicated in some aggressive strains of HPV-6 (Boshart and zur Hausen 1986; Rando et al. 1986). To test the possible biological relevance of these duplications, they cloned tandem arrays of the enhancer and demonstrated, using a chloramphenicol acetyltransferase (CAT) assay, that they led to dramatically increased transcription proportional to copy number. Using the CAT assays, the authors found that the E2 proteins of several papillomavirus types can cross-stimulate the enhancers of most other types. This suggests that prior infection of a tissue with one papillomavirus type may provide a helper effect for superinfection and might account fo the HPV-6/HPV-16 coinfections in condylomata that they have observed

The full-length E1-circumflexE4 protein of human papillomavirus type 18 modulates differentiation-dependent viral DNA amplification and late gene expression

International Nuclear Information System (INIS)

Wilson, Regina; Ryan, Gordon B.; Knight, Gillian L.; Laimins, Laimonis A.; Roberts, Sally

2007-01-01

Activation of the productive phase of the human papillomavirus (HPV) life cycle in differentiated keratinocytes is coincident with high-level expression of E1-circumflexE4 protein. To determine the role of E1-circumflexE4 in the HPV replication cycle, we constructed HPV18 mutant genomes in which expression of the full-length E1-circumflexE4 protein was abrogated. Undifferentiated keratinocytes containing mutant genomes showed enhanced proliferation when compared to cells containing wildtype genomes, but there were no differences in maintenance of viral episomes. Following differentiation, cells with mutant genomes exhibited reduced levels of viral DNA amplification and late gene expression, compared to wildtype genome-containing cells. This indicates that HPV18 E1-circumflexE4 plays an important role in regulating HPV late functions, and it may also function in the early phase of the replication cycle. Our finding that full-length HPV18 E1-circumflexE4 protein plays a significant role in promoting viral genome amplification concurs with a similar report with HPV31, but is in contrast to an HPV11 study where viral DNA amplification was not dependent on full-length E1-circumflexE4 expression, and to HPV16 where only C-terminal truncations in E1-circumflexE4 abrogated vegetative genome replication. This suggests that type-specific differences exist between various E1-circumflexE4 proteins

[Molecular aspects of human papillomaviruses and their relation to uterine cervix cancer].

Science.gov (United States)

García-Carrancá, A; Gariglio, P V

1993-01-01

Papillomaviruses (wart viruses) are responsible for the development of benign and malignant epithelial lesions in mammals. More than 60 different types of human papillomaviruses (HPVs) have been isolated to date. Some of them are major candidates as etiologic agents in cervical cancer. DNA from HPV types 16, 18 and 33 is usually found integrated in about 90 percent of genital carcinomas. Integration of the viral DNA into the cellular genome may be an important step towards the development of malignancy. Two early genes of HPVs (E6 y E7) are involved in cellular transformation. Another early gene (E2) participates in gene control by directly binding to conserved DNA motifs in the viral genome. Several protein factors of viral and cellular origin interact with the regulatory region of HPVs and participate in the regulation transcription of oncogenes E6 and E7. Cellular factors, such as immune system and oncogene and anti-oncogene alterations, seem to play an important role in papillomavirus-associated cervical carcinogenesis.

Evaluation of immunological cross-reactivity between clade A9 high-risk human papillomavirus types on the basis of E6-Specific CD4+ memory T cell responses

NARCIS (Netherlands)

van den Hende, Muriel; Redeker, Anke; Kwappenberg, Kitty M. C.; Franken, Kees L. M. C.; Drijfhout, Jan W.; Oostendorp, Jaap; Valentijn, A. Rob P. M.; Fathers, Loraine M.; Welters, Marij J. P.; Melief, Cornelis J. M.; Kenter, Gemma G.; van der Burg, Sjoerd H.; Offringa, Rienk

2010-01-01

CD4(+) T cell responses against the E6 oncoprotein of human papillomavirus (HPV) type 16 and 5 closely related members of clade A9 (HPV31, 33, 35, 52, and 58) were charted in peripheral blood mononuclear cell cultures from healthy subjects and patients who underwent HPV16 E6/E7-specific vaccination.

A Chlamydomonas-derived Human Papillomavirus 16 E7 vaccine induces specific tumor protection.

Directory of Open Access Journals (Sweden)

Olivia C Demurtas

Full Text Available The E7 protein of the Human Papillomavirus (HPV type 16, being involved in malignant cellular transformation, represents a key antigen for developing therapeutic vaccines against HPV-related lesions and cancers. Recombinant production of this vaccine antigen in an active form and in compliance with good manufacturing practices (GMP plays a crucial role for developing effective vaccines. E7-based therapeutic vaccines produced in plants have been shown to be active in tumor regression and protection in pre-clinical models. However, some drawbacks of in whole-plant vaccine production encouraged us to explore the production of the E7-based therapeutic vaccine in Chlamydomonas reinhardtii, an organism easy to grow and transform and fully amenable to GMP guidelines.An expression cassette encoding E7GGG, a mutated, attenuated form of the E7 oncoprotein, alone or as a fusion with affinity tags (His6 or FLAG, under the control of the C. reinhardtii chloroplast psbD 5' UTR and the psbA 3' UTR, was introduced into the C. reinhardtii chloroplast genome by homologous recombination. The protein was mostly soluble and reached 0.12% of total soluble proteins. Affinity purification was optimized and performed for both tagged forms. Induction of specific anti-E7 IgGs and E7-specific T-cell proliferation were detected in C57BL/6 mice vaccinated with total Chlamydomonas extract and with affinity-purified protein. High levels of tumor protection were achieved after challenge with a tumor cell line expressing the E7 protein.The C. reinhardtii chloroplast is a suitable expression system for the production of the E7GGG protein, in a soluble, immunogenic form. The production in contained and sterile conditions highlights the potential of microalgae as alternative platforms for the production of vaccines for human uses.

Ultrasensitive quantitation of human papillomavirus type 16 E6 oncogene sequences by nested real time PCR

Directory of Open Access Journals (Sweden)

López-Revilla Rubén

2010-05-01

Full Text Available Abstract Background We have developed an ultrasensitive method based on conventional PCR preamplification followed by nested amplification through real time PCR (qPCR in the presence of the DNA intercalating agent EvaGreen. Results Amplification mixtures calibrated with a known number of pHV101 copies carrying a 645 base pair (bp-long insert of the human papillomavirus type 16 (HPV16 E6 oncogene were used to generate the E6-1 amplicon of 645 bp by conventional PCR and then the E6-2 amplicon of 237 bp by nested qPCR. Direct and nested qPCR mixtures for E6-2 amplification corresponding to 2.5 × 102-2.5 × 106 initial pHV101 copies had threshold cycle (Ct values in the ranges of 18.7-29.0 and 10.0-25.0, respectively. The Ct of qPCR mixtures prepared with 1/50 volumes of preamplified mixtures containing 50 ng of DNA of the SiHa cell line (derived from an invasive cervical cancer with one HPV16 genome per cell was 19.9. Thermal fluorescence extinction profiles of E6-2 amplicons generated from pHV101 and SiHa DNA were identical, with a peak at 85.5°C. Conclusions Our method based on conventional preamplification for 15 cycles increased 10,750 times the sensitivity of nested qPCR for the quantitation of the E6 viral oncogene and confirmed that the SiHa cell line contains one E6-HPV16 copy per cell.

Identification and characterization of a cluster of transcription start sites located in the E6 ORF of human papillomavirus type 16

DEFF Research Database (Denmark)

Rosenstierne, Maiken W; Vinther, Jeppe; Hansen, Christina N

2003-01-01

Human papillomavirus type 16 (HPV-16) is the prototype strain among the malignant types of HPV in the western world. The main promoter, P97, located in front of the E6 ORF, has been shown to control expression of the oncogenes E6 and E7. These oncogenes are expressed continuously in HPV-16......-transformed cells. In contrast to malignant HPV types, non-malignant HPV types have separate promoters driving the expression of E6 and E7. Experiments have shown that the translation of E7 is more efficient from monocistronic than bicistronic transcripts encoding both E6 and E7. Here, identification...... of a cluster of transcription start sites located in the E6 ORF of HPV-16 is presented. Transcripts from this region contain the E7 ORF as the first reading frame. The cluster consists of multiple transcription start sites located around nt 441. Additional transcription start sites were identified in a cluster...

Mitotic control of human papillomavirus genome-containing cells is regulated by the function of the PDZ-binding motif of the E6 oncoprotein

Science.gov (United States)

Marsh, Elizabeth K.; Delury, Craig P.; Davies, Nicholas J.; Weston, Christopher J.; Miah, Mohammed A.L.; Banks, Lawrence; Parish, Joanna L.

2017-01-01

The function of a conserved PDS95/DLG1/ZO1 (PDZ) binding motif (E6 PBM) at the C-termini of E6 oncoproteins of high-risk human papillomavirus (HPV) types contributes to the development of HPV-associated malignancies. Here, using a primary human keratinocyte-based model of the high-risk HPV18 life cycle, we identify a novel link between the E6 PBM and mitotic stability. In cultures containing a mutant genome in which the E6 PBM was deleted there was an increase in the frequency of abnormal mitoses, including multinucleation, compared to cells harboring the wild type HPV18 genome. The loss of the E6 PBM was associated with a significant increase in the frequency of mitotic spindle defects associated with anaphase and telophase. Furthermore, cells carrying this mutant genome had increased chromosome segregation defects and they also exhibited greater levels of genomic instability, as shown by an elevated level of centromere-positive micronuclei. In wild type HPV18 genome-containing organotypic cultures, the majority of mitotic cells reside in the suprabasal layers, in keeping with the hyperplastic morphology of the structures. However, in mutant genome-containing structures a greater proportion of mitotic cells were retained in the basal layer, which were often of undefined polarity, thus correlating with their reduced thickness. We conclude that the ability of E6 to target cellular PDZ proteins plays a critical role in maintaining mitotic stability of HPV infected cells, ensuring stable episome persistence and vegetative amplification. PMID:28061478

Mitotic control of human papillomavirus genome-containing cells is regulated by the function of the PDZ-binding motif of the E6 oncoprotein.

Science.gov (United States)

Marsh, Elizabeth K; Delury, Craig P; Davies, Nicholas J; Weston, Christopher J; Miah, Mohammed A L; Banks, Lawrence; Parish, Joanna L; Higgs, Martin R; Roberts, Sally

2017-03-21

The function of a conserved PDS95/DLG1/ZO1 (PDZ) binding motif (E6 PBM) at the C-termini of E6 oncoproteins of high-risk human papillomavirus (HPV) types contributes to the development of HPV-associated malignancies. Here, using a primary human keratinocyte-based model of the high-risk HPV18 life cycle, we identify a novel link between the E6 PBM and mitotic stability. In cultures containing a mutant genome in which the E6 PBM was deleted there was an increase in the frequency of abnormal mitoses, including multinucleation, compared to cells harboring the wild type HPV18 genome. The loss of the E6 PBM was associated with a significant increase in the frequency of mitotic spindle defects associated with anaphase and telophase. Furthermore, cells carrying this mutant genome had increased chromosome segregation defects and they also exhibited greater levels of genomic instability, as shown by an elevated level of centromere-positive micronuclei. In wild type HPV18 genome-containing organotypic cultures, the majority of mitotic cells reside in the suprabasal layers, in keeping with the hyperplastic morphology of the structures. However, in mutant genome-containing structures a greater proportion of mitotic cells were retained in the basal layer, which were often of undefined polarity, thus correlating with their reduced thickness. We conclude that the ability of E6 to target cellular PDZ proteins plays a critical role in maintaining mitotic stability of HPV infected cells, ensuring stable episome persistence and vegetative amplification.

Human papillomavirus E6 and E7 oncoproteins alter cell cycle progression but not radiosensitivity of carcinoma cells treated with low-dose-rate radiation

International Nuclear Information System (INIS)

DeWeese, Theodore L.; Walsh, Jonathan C.; Dillehay, Larry E.; Kessis, Theodore D.; Hedrick, Lora; Cho, Kathleen R.; Nelson, William G.

1997-01-01

Purpose: Low-dose-rate radiation therapy has been widely used in the treatment of urogenital malignancies. When continuously exposed to low-dose-rate ionizing radiation, target cancer cells typically exhibit abnormalities in replicative cell-cycle progression. Cancer cells that arrest in the G2 phase of the cell cycle when irradiated may become exquisitely sensitive to killing by further low-dose-rate radiation treatment. Oncogenic human papillomaviruses (HPVs), which play a major role in the pathogenesis of uterine cervix cancers and other urogenital cancers, encode E6 and E7 transforming proteins known to abrogate a p53-dependent G1 cell-cycle checkpoint activated by conventional acute-dose radiation exposure. This study examined whether expression of HPV E6 and E7 oncoproteins by cancer cells alters the cell-cycle redistribution patterns accompanying low-dose-rate radiation treatment, and whether such alterations in cell-cycle redistribution affect cancer cell killing. Methods and Materials: RKO carcinoma cells, which contain wild-type P53 alleles, and RKO cell sublines genetically engineered to express HPV E6 and E7 oncoproteins, were treated with low-dose-rate (0.25-Gy/h) radiation and then assessed for p53 and p21WAF1/CIP1 polypeptide induction by immunoblot analysis, for cell-cycle redistribution by flow cytometry, and for cytotoxicity by clonogenic survival assay. Results: Low-dose-rate radiation of RKO carcinoma cells triggered p53 polypeptide elevations, p21WAF1/CIP1 induction, and arrest in the G1 and G2 phases of the cell cycle. In contrast, RKO cells expressing E6 and E7 transforming proteins from high-risk oncogenic HPVs (HPV 16) arrested in G2, but failed to arrest in G1, when treated with low-dose-rate ionizing radiation. Abrogation of the G1 cell-cycle checkpoint activated by low-dose-rate radiation exposure appeared to be a characteristic feature of transforming proteins from high-risk oncogenic HPVs: RKO cells expressing E6 from a low

The Human Papillomavirus E6 PDZ Binding Motif: From Life Cycle to Malignancy

Directory of Open Access Journals (Sweden)

Ketaki Ganti

2015-07-01

Full Text Available Cancer-causing HPV E6 oncoproteins are characterized by the presence of a PDZ binding motif (PBM at their extreme carboxy terminus. It was long thought that this region of E6 had a sole function to confer interaction with a defined set of cellular substrates. However, more recent studies have shown that the E6 PBM has a complex pattern of regulation, whereby phosphorylation within the PBM can regulate interaction with two classes of cellular proteins: those containing PDZ domains and the members of the 14-3-3 family of proteins. In this review, we explore the roles that the PBM and its ligands play in the virus life cycle, and subsequently how these can inadvertently contribute towards the development of malignancy. We also explore how subtle alterations in cellular signal transduction pathways might result in aberrant E6 phosphorylation, which in turn might contribute towards disease progression.

High-Risk Human Papillomaviral Oncogenes E6 and E7 Target Key Cellular Pathways to Achieve Oncogenesis.

Science.gov (United States)

Yeo-Teh, Nicole S L; Ito, Yoshiaki; Jha, Sudhakar

2018-06-08

Infection with high-risk human papillomavirus (HPV) has been linked to several human cancers, the most prominent of which is cervical cancer. The integration of the viral genome into the host genome is one of the manners in which the viral oncogenes E6 and E7 achieve persistent expression. The most well-studied cellular targets of the viral oncogenes E6 and E7 are p53 and pRb, respectively. However, recent research has demonstrated the ability of these two viral factors to target many more cellular factors, including proteins which regulate epigenetic marks and splicing changes in the cell. These have the ability to exert a global change, which eventually culminates to uncontrolled proliferation and carcinogenesis.

Acute dose and low dose-rate irradiation of carcinoma cells expressing human papillomavirus E6 and E7 oncoproteins - the significance of p53, Rb and G1 arrest status

International Nuclear Information System (INIS)

DeWeese, Theodore L.; Walsh, Jonathan C.; Dillehay, Larry E.; Shao, Y.; Kessis, Theodore D.; Cho, Kathleen R.; Nelson, William G.

1995-01-01

Purpose: The development of carcinomas in a number of sites including the cervix, vulva and anus have been associated with cellular infection by human papillomaviruses (HPV), including HPV 16 and HPV 18. The mechanism by which these viruses contribute to tumor development or progression seems in part to be related to the integration of the viral genome into the host cells DNA, and the binding of p53 protein by the HPV E6 oncoprotein as well as the binding of the retinoblastoma (Rb) protein and Rb-like proteins by the HPV E7 oncoprotein. These interactions lead to loss of p53 and Rb function including loss of the G 1 cell cycle checkpoint. Although it is believed that both p53 and Rb play a role in the radiosensitivity of the cell, whether alteration in either protein enhances or diminishes cellular radiation response is not clear from the literature. Because HPV-associated tumors such as cervical cancer are often treated with acute dose and/or low dose-rate radiation, we set out to evaluate the radiation response of several carcinoma cell sublines expressing either oncogenic E6 or E7 to both types of radiation, and to determine if p53/Rb dependent G 1 arrest is an important determinant of cell fate after irradiation. Materials and Methods: We have previously developed a series of RKO colorectal carcinoma cell sublines expressing both low-risk (HPV 11) and high-risk (HPV 16) E6 and E7 genes. p53-dependent G 1 arrest is intact in RKO parental cells and cells expressing low-risk E6 proteins, while the G 1 arrest is abrogated in cells expressing high-risk E6 or E7. Clonogenic survival was assessed after exposure to acute dose (1 Gy/min) and low dose-rate (0.25 Gy/hour) radiation. The radiobiologic parameters α, β and the surviving fraction at 2 Gy (SF2) were determined. SDS-PAGE/immunoblotting was carried out to assess both p53 and p21 WAF1/CIP1 levels after exposure to radiation. Flow cytometry was performed before and after exposure to low dose-rate radiation to

In Vitro and In Vivo Synergistic Therapeutic Effect of Cisplatin with Human Papillomavirus16 E6/E7 CRISPR/Cas9 on Cervical Cancer Cell Line

Directory of Open Access Journals (Sweden)

Shuai Zhen

2016-12-01

Full Text Available PURPOSE: Human papillomavirus (HPV type 16 is one of the major etiologic factors of cervical cancer. Our study aims to investigate the potentiality of the antiviral clustered regularly interspaced short palindromic repeat (CRISPR/CRISPR-associated Cas9 system (CRISPR/Cas9 targeting the E6 and E7 oncogenes of HPV16 as a potential chemosensitizer of cisplatin (cis-diaminedichloroplatinum II; CDDP for cervical cancer. METHODS: Specifically, the therapeutic efficacy of combination of CDDP and HPV16 E6 + E7-CRISPR/Cas9 was assessed in cervical cancer cells and cervical cancer xenograft models. RESULTS: In vitro experiments showed that long-term exposure of SiHa cells to the HPV16 E6 + E7-CRISPR/Cas9 induced apoptosis, and its pro-apoptosis effect became more obvious when combined with CDDP. In vivo study found the efficacy of the combination of HPV16 E6 + E7-CRISPR/Cas9 and CDDP were superior to either of the treatments in term of apoptosis induction and metastasis inhibition. CONCLUSION: Collectively, our results suggested that HPV16 E6 + E7-CRISPR/Cas9 could be an effective sensitizer of CDDP chemotherapy in cervical cancer.

Degradation of p53 by human Alphapapillomavirus E6 proteins shows a stronger correlation with phylogeny than oncogenicity.

Directory of Open Access Journals (Sweden)

Leiping Fu

2010-09-01

Full Text Available Human Papillomavirus (HPV E6 induced p53 degradation is thought to be an essential activity by which high-risk human Alphapapillomaviruses (alpha-HPVs contribute to cervical cancer development. However, most of our understanding is derived from the comparison of HPV16 and HPV11. These two viruses are relatively distinct viruses, making the extrapolation of these results difficult. In the present study, we expand the tested strains (types to include members of all known HPV species groups within the Alphapapillomavirus genus.We report the biochemical activity of E6 proteins from 27 HPV types representing all alpha-HPV species groups to degrade p53 in human cells. Expression of E6 from all HPV types epidemiologically classified as group 1 carcinogens significantly reduced p53 levels. However, several types not associated with cancer (e.g., HPV53, HPV70 and HPV71 were equally active in degrading p53. HPV types within species groups alpha 5, 6, 7, 9 and 11 share a most recent common ancestor (MRCA and all contain E6 ORFs that degrade p53. A unique exception, HPV71 E6 ORF that degraded p53 was outside this clade and is one of the most prevalent HPV types infecting the cervix in a population-based study of 10,000 women. Alignment of E6 ORFs identified an amino acid site that was highly correlated with the biochemical ability to degrade p53. Alteration of this amino acid in HPV71 E6 abrogated its ability to degrade p53, while alteration of this site in HPV71-related HPV90 and HPV106 E6s enhanced their capacity to degrade p53.These data suggest that the alpha-HPV E6 proteins' ability to degrade p53 is an evolved phenotype inherited from a most recent common ancestor of the high-risk species that does not always segregate with carcinogenicity. In addition, we identified an amino-acid residue strongly correlated with viral p53 degrading potential.

The Subcellular Localisation of the Human Papillomavirus (HPV 16 E7 Protein in Cervical Cancer Cells and Its Perturbation by RNA Aptamers

Directory of Open Access Journals (Sweden)

Özlem Cesur

2015-06-01

Full Text Available Human papillomavirus (HPV is the most common viral infection of the reproductive tract, affecting both men and women. High-risk oncogenic types are responsible for almost 90% of anogenital and oropharyngeal cancers including cervical cancer. Some of the HPV “early” genes, particularly E6 and E7, are known to act as oncogenes that promote tumour growth and malignant transformation. Most notably, HPV-16 E7 interacts with the tumour suppressor protein pRb, promoting its degradation, leading to cell cycle dysregulation in infected cells. We have previously shown that an RNA aptamer (termed A2 selectively binds to HPV16 E7 and is able to induce apoptosis in HPV16-transformed cervical carcinoma cell lines (SiHa through reduction of E7 levels. In this study, we investigated the effects of the A2 aptamer on E7 localisation in order to define its effects on E7 activity. We demonstrate for the first time that E7 localised to the plasma membrane. In addition, we show that A2 enhanced E7 localisation in the ER and that the A2-mediated reduction of E7 was not associated with proteasomal degradation. These data suggest that A2 perturbs normal E7 trafficking through promoting E7 ER retention.

Computational identification, characterization and validation of potential antigenic peptide vaccines from hrHPVs E6 proteins using immunoinformatics and computational systems biology approaches.

Directory of Open Access Journals (Sweden)

Abbas Khan

Full Text Available High-risk human papillomaviruses (hrHPVs are the most prevalent viruses in human diseases including cervical cancers. Expression of E6 protein has already been reported in cervical cancer cases, excluding normal tissues. Continuous expression of E6 protein is making it ideal to develop therapeutic vaccines against hrHPVs infection and cervical cancer. Therefore, we carried out a meta-analysis of multiple hrHPVs to predict the most potential prophylactic peptide vaccines. In this study, immunoinformatics approach was employed to predict antigenic epitopes of hrHPVs E6 proteins restricted to 12 Human HLAs to aid the development of peptide vaccines against hrHPVs. Conformational B-cell and CTL epitopes were predicted for hrHPVs E6 proteins using ElliPro and NetCTL. The potential of the predicted peptides were tested and validated by using systems biology approach considering experimental concentration. We also investigated the binding interactions of the antigenic CTL epitopes by using docking. The stability of the resulting peptide-MHC I complexes was further studied by molecular dynamics simulations. The simulation results highlighted the regions from 46-62 and 65-76 that could be the first choice for the development of prophylactic peptide vaccines against hrHPVs. To overcome the worldwide distribution, the predicted epitopes restricted to different HLAs could cover most of the vaccination and would help to explore the possibility of these epitopes for adaptive immunotherapy against HPVs infections.

Incoming human papillomavirus 16 genome is lost in PML protein-deficient HaCaT keratinocytes.

Science.gov (United States)

Bienkowska-Haba, Malgorzata; Luszczek, Wioleta; Keiffer, Timothy R; Guion, Lucile G M; DiGiuseppe, Stephen; Scott, Rona S; Sapp, Martin

2017-05-01

Human papillomaviruses (HPVs) target promyelocytic leukemia (PML) nuclear bodies (NBs) during infectious entry and PML protein is important for efficient transcription of incoming viral genome. However, the transcriptional down regulation was shown to be promoter-independent in that heterologous promoters delivered by papillomavirus particles were also affected. To further investigate the role of PML protein in HPV entry, we used small hairpin RNA to knockdown PML protein in HaCaT keratinocytes. Confirming previous findings, PML knockdown in HaCaT cells reduced HPV16 transcript levels significantly following infectious entry without impairing binding and trafficking. However, when we quantified steady-state levels of pseudogenomes in interphase cells, we found strongly reduced genome levels compared with parental HaCaT cells. Because nuclear delivery was comparable in both cell lines, we conclude that viral pseudogenome must be removed after successful nuclear delivery. Transcriptome analysis by gene array revealed that PML knockdown in clonal HaCaT cells was associated with a constitutive interferon response. Abrogation of JAK1/2 signaling prevented genome loss, however, did not restore viral transcription. In contrast, knockdown of PML protein in HeLa cells did not affect HPV genome delivery and transcription. HeLa cells are transformed by HPV18 oncogenes E6 and E7, which have been shown to interfere with the JAK/Stat signaling pathway. Our data imply that PML NBs protect incoming HPV genomes. Furthermore, they provide evidence that PML NBs are key regulators of the innate immune response in keratinocytes. Promyelocytic leukemia nuclear bodies (PML NBs) are important for antiviral defense. Many DNA viruses target these subnuclear structures and reorganize them. Reorganization of PML NBs by viral proteins is important for establishment of infection. In contrast, HPVs require the presence of PML protein for efficient transcription of incoming viral genome. Our

The human papillomavirus (HPV) E6 oncoproteins promotes nuclear localization of active caspase 8

Energy Technology Data Exchange (ETDEWEB)

Manzo-Merino, Joaquin [Unidad de Investigación Biomédica en Cáncer, Instituto Nacional de Cancerología, México/Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México. Av. San Fernando No. 22, Col. Sección XVI, Tlalpan 14080 (Mexico); Massimi, Paola [International Centre for Genetic Engineering and Biotechnology, Padriciano 99, I-34149 Trieste (Italy); Lizano, Marcela, E-mail: lizanosoberon@gmail.com [Unidad de Investigación Biomédica en Cáncer, Instituto Nacional de Cancerología, México/Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México. Av. San Fernando No. 22, Col. Sección XVI, Tlalpan 14080 (Mexico); Banks, Lawrence, E-mail: banks@icgeb.org [International Centre for Genetic Engineering and Biotechnology, Padriciano 99, I-34149 Trieste (Italy)

2014-02-15

The HPV-16 E6 and E6{sup ⁎} proteins have been shown previously to be capable of regulating caspase 8 activity. We now show that the capacity of E6 to interact with caspase 8 is common to diverse HPV types, being also seen with HPV-11 E6, HPV-18 E6 and HPV-18 E6{sup ⁎}. Unlike most E6-interacting partners, caspase 8 does not appear to be a major proteasomal target of E6, but instead E6 appears able to stimulate caspase 8 activation, without affecting the overall apoptotic activity. This would appear to be mediated in part by the ability of the HPV E6 oncoproteins to recruit active caspase 8 to the nucleus. - Highlights: • Multiple HPV E6 oncoproteins interact with the caspase 8 DED domain. • HPV E6 stimulates activation of caspase 8. • HPV E6 promotes nuclear accumulation of caspase 8.

The human papillomavirus (HPV) E6 oncoproteins promotes nuclear localization of active caspase 8

International Nuclear Information System (INIS)

Manzo-Merino, Joaquin; Massimi, Paola; Lizano, Marcela; Banks, Lawrence

2014-01-01

The HPV-16 E6 and E6 ⁎ proteins have been shown previously to be capable of regulating caspase 8 activity. We now show that the capacity of E6 to interact with caspase 8 is common to diverse HPV types, being also seen with HPV-11 E6, HPV-18 E6 and HPV-18 E6 ⁎ . Unlike most E6-interacting partners, caspase 8 does not appear to be a major proteasomal target of E6, but instead E6 appears able to stimulate caspase 8 activation, without affecting the overall apoptotic activity. This would appear to be mediated in part by the ability of the HPV E6 oncoproteins to recruit active caspase 8 to the nucleus. - Highlights: • Multiple HPV E6 oncoproteins interact with the caspase 8 DED domain. • HPV E6 stimulates activation of caspase 8. • HPV E6 promotes nuclear accumulation of caspase 8

Mathematical Modeling of E6-p53 interactions in Cervical Cancer

Science.gov (United States)

Khattak, Faryal; Haseeb, Muhammad; Fazal, Sahar; Bhatti, A I; Ullah, Mukhtar

2017-04-01

Background: Cervical cancer is the third most common cancer in women throughout the world. The human papillomavirus (HPV) E6 viral protein plays an essential role in proteasomal degradation of the cancer suppressant protein p53. As a result, p53 negative regulation and apoptosis relevant activities are abrogated, facilitating development of cervical cancer. Methods: A mathematical model of E6-p53 interactions was developed using mathematical laws. In-silico simulations were carried out on CellDesigner and as a test case the small molecule drug RITA was considered for its ability to rescue the functions of tumor suppressor p53 by inhibiting E6 mediated proteasomal degradation. Results: Using a computational model we scrutinized how p53 responds to RITA, and chemical reactions of this small molecule drug were incorporated to perceive the full effects. The evolved strategy allowed the p53 response and rescue of its tumor suppressor function to be delineated, RITA being found to block p53 interactions with E6 associated proteins. Conclusion: We could develop a model of E6-p53 interactions with incorporation of actions of the small molecule drug RITA. Suppression of E6 associated proteins by RITA induces accumulation of tumor suppressant p53. Using CellDesigner to encode the model ensured that it can be easily modified and extended as more data become available. This strategy should play an effective role in the development of therapies against cancer. Creative Commons Attribution License

Cervical Cancers Require the Continuous Expression of the Human Papillomavirus Type 16 E7 Oncoprotein Even in the Presence of the Viral E6 Oncoprotein

Science.gov (United States)

Jabbar, Sean F.; Park, Soyeong; Schweizer, Johannes; Berard-Bergery, Marthe; Pitot, Henry C.; Lee, Denis; Lambert, Paul F.

2012-01-01

High-risk human papillomaviruses (HPV), such as HPV-16, are etiologic agents of a variety of anogenital and oral malignancies, including nearly all cases of cervical cancer. Cervical cancers arising in transgenic mice that express HPV-16 E7 in an inducible manner require the continuous expression of E7 for their maintenance. However, in HPV-associated cancers in vivo, E6 and E7 invariably are co-expressed. In this study, we investigated whether cervical cancers rely on the continuous expression of E7 in the context of constitutively expressed E6. We placed the inducible HPV-16 E7 transgene onto a background in which HPV-16 E6 was constitutively expressed. In transgenic mice with high-grade cervical dysplastic lesions and cervical cancer, repressing the expression of E7 led to the regression of all cancers and the vast majority of high-grade dysplastic lesions. In addition, cervical cancers were occasionally observed in transgenic mice in which E7 was repressed and then re-expressed. Our findings therefore indicate that even in the presence of constitutively expressed E6, the continuous expression of E7 is required for the maintenance of cervical cancers and most precancerous lesions. These data have important implications for the potential clinical use of drugs designed to inhibit the expression and/or function of E7 to treat HPV-associated cancers. PMID:22700879

human papillomaviruses E6 and E7 oncoproteins

Indian Academy of Sciences (India)

Unknown

Recent work has uncovered new cellular partners for these .... Hence it is evident that a fine balance exists between these that govern ... still suggest that E7 can have a more global effect on the general .... towards malignancy), increases life span of the cells. E6 ..... nism when expressed alone in HPV positive/negative cell.

Evasion of host immune defenses by human papillomavirus.

Science.gov (United States)

Westrich, Joseph A; Warren, Cody J; Pyeon, Dohun

2017-03-02

A majority of human papillomavirus (HPV) infections are asymptomatic and self-resolving in the absence of medical interventions. Various innate and adaptive immune responses, as well as physical barriers, have been implicated in controlling early HPV infections. However, if HPV overcomes these host immune defenses and establishes persistence in basal keratinocytes, it becomes very difficult for the host to eliminate the infection. The HPV oncoproteins E5, E6, and E7 are important in regulating host immune responses. These oncoproteins dysregulate gene expression, protein-protein interactions, posttranslational modifications, and cellular trafficking of critical host immune modulators. In addition to the HPV oncoproteins, sequence variation and dinucleotide depletion in papillomavirus genomes has been suggested as an alternative strategy for evasion of host immune defenses. Since anti-HPV host immune responses are also considered to be important for antitumor immunity, immune dysregulation by HPV during virus persistence may contribute to immune suppression essential for HPV-associated cancer progression. Here, we discuss cellular pathways dysregulated by HPV that allow the virus to evade various host immune defenses. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

A novel papillomavirus in Adélie penguin (Pygoscelis adeliae) faeces sampled at the Cape Crozier colony, Antarctica.

Science.gov (United States)

Varsani, Arvind; Kraberger, Simona; Jennings, Scott; Porzig, Elizabeth L; Julian, Laurel; Massaro, Melanie; Pollard, Annie; Ballard, Grant; Ainley, David G

2014-06-01

Papillomaviruses are epitheliotropic viruses that have circular dsDNA genomes encapsidated in non-enveloped virions. They have been found to infect a variety of mammals, reptiles and birds, but so far they have not been found in amphibians. Using a next-generation sequencing de novo assembly contig-informed recovery, we cloned and Sanger sequenced the complete genome of a novel papillomavirus from the faecal matter of Adélie penguins (Pygoscelis adeliae) nesting on Ross Island, Antarctica. The genome had all the usual features of a papillomavirus and an E9 ORF encoding a protein of unknown function that is found in all avian papillomaviruses to date. This novel papillomavirus genome shared ~60 % pairwise identity with the genomes of the other three known avian papillomaviruses: Fringilla coelebs papillomavirus 1 (FcPV1), Francolinus leucoscepus papillomavirus 1 (FlPV1) and Psittacus erithacus papillomavirus 1. Pairwise identity analysis and phylogenetic analysis of the major capsid protein gene clearly indicated that it represents a novel species, which we named Pygoscelis adeliae papillomavirus 1 (PaCV1). No evidence of recombination was detected in the genome of PaCV1, but we did detect a recombinant region (119 nt) in the E6 gene of FlPV1 with the recombinant region being derived from ancestral FcPV1-like sequences. Previously only paramyxoviruses, orthomyxoviruses and avian pox viruses have been genetically identified in penguins; however, the majority of penguin viral identifications have been based on serology or histology. This is the first report, to our knowledge, of a papillomavirus associated with a penguin species. © 2014 The Authors.

DNA Damage Reduces the Quality, but Not the Quantity of Human Papillomavirus 16 E1 and E2 DNA Replication.

Science.gov (United States)

Bristol, Molly L; Wang, Xu; Smith, Nathan W; Son, Minkyeong P; Evans, Michael R; Morgan, Iain M

2016-06-22

Human papillomaviruses (HPVs) are causative agents in almost all cervical carcinomas. HPVs are also causative agents in head and neck cancer, the cases of which are increasing rapidly. Viral replication activates the DNA damage response (DDR) pathway; associated proteins are recruited to replication foci, and this pathway may serve to allow for viral genome amplification. Likewise, HPV genome double-strand breaks (DSBs) could be produced during replication and could lead to linearization and viral integration. Many studies have shown that viral integration into the host genome results in unregulated expression of the viral oncogenes, E6 and E7, promoting HPV-induced carcinogenesis. Previously, we have demonstrated that DNA-damaging agents, such as etoposide, or knocking down viral replication partner proteins, such as topoisomerase II β binding protein I (TopBP1), does not reduce the level of DNA replication. Here, we investigated whether these treatments alter the quality of DNA replication by HPV16 E1 and E2. We confirm that knockdown of TopBP1 or treatment with etoposide does not reduce total levels of E1/E2-mediated DNA replication; however, the quality of replication is significantly reduced. The results demonstrate that E1 and E2 continue to replicate under genomically-stressed conditions and that this replication is mutagenic. This mutagenesis would promote the formation of substrates for integration of the viral genome into that of the host, a hallmark of cervical cancer.

DNA Damage Reduces the Quality, but Not the Quantity of Human Papillomavirus 16 E1 and E2 DNA Replication

Directory of Open Access Journals (Sweden)

Molly L. Bristol

2016-06-01

Full Text Available Human papillomaviruses (HPVs are causative agents in almost all cervical carcinomas. HPVs are also causative agents in head and neck cancer, the cases of which are increasing rapidly. Viral replication activates the DNA damage response (DDR pathway; associated proteins are recruited to replication foci, and this pathway may serve to allow for viral genome amplification. Likewise, HPV genome double-strand breaks (DSBs could be produced during replication and could lead to linearization and viral integration. Many studies have shown that viral integration into the host genome results in unregulated expression of the viral oncogenes, E6 and E7, promoting HPV-induced carcinogenesis. Previously, we have demonstrated that DNA-damaging agents, such as etoposide, or knocking down viral replication partner proteins, such as topoisomerase II β binding protein I (TopBP1, does not reduce the level of DNA replication. Here, we investigated whether these treatments alter the quality of DNA replication by HPV16 E1 and E2. We confirm that knockdown of TopBP1 or treatment with etoposide does not reduce total levels of E1/E2-mediated DNA replication; however, the quality of replication is significantly reduced. The results demonstrate that E1 and E2 continue to replicate under genomically-stressed conditions and that this replication is mutagenic. This mutagenesis would promote the formation of substrates for integration of the viral genome into that of the host, a hallmark of cervical cancer.

Activities of E7 promoters in the human papillomavirus type 16 genome during cell differentiation

DEFF Research Database (Denmark)

Hansen, Christina Neigaard; Nielsen, Lone; Norrild, Bodil

2010-01-01

Worldwide, one of the most common cancer forms diagnosed in women is cervical cancer induced by infections with high-risk human papillomaviruses (HPVs) with HPV type 16 (HPV-16) being the most frequently identified. The oncogenicity is caused mainly by expression of the oncogenes E6 and E7 leadin...

Photodynamic tissue adhesion with chlorin(e6) protein conjugates.

Science.gov (United States)

Khadem, J; Veloso, A A; Tolentino, F; Hasan, T; Hamblin, M R

1999-12-01

To test the hypothesis that a photodynamic laser-activated tissue solder would perform better in sealing scleral incisions when the photosensitizer was covalently linked to the protein than when it was noncovalently mixed. Conjugates and mixtures were prepared between the photosensitizer chlorin(e6) and various proteins (albumin, fibrinogen, and gelatin) in different ratios and used to weld penetrating scleral incisions made in human cadaveric eyes. A blue-green (488-514 nm) argon laser activated the adhesive, and the strength of the closure was measured by increasing the intraocular pressure until the wound showed leakage. Both covalent conjugates and noncovalent mixtures showed a light dose-dependent increase in leaking pressure. A preparation of albumin chlorin(e6) conjugate with additional albumin added (2.5 protein to chlorin(e6) molar ratio) showed significantly higher weld strength than other protein conjugates and mixtures. This is the first report of dye-protein conjugates as tissue solders. These conjugates may have applications in ophthalmology.

Requirement for the E1 Helicase C-Terminal Domain in Papillomavirus DNA Replication In Vivo.

Science.gov (United States)

Bergvall, Monika; Gagnon, David; Titolo, Steve; Lehoux, Michaël; D'Abramo, Claudia M; Melendy, Thomas; Archambault, Jacques

2016-01-06

The papillomavirus (PV) E1 helicase contains a conserved C-terminal domain (CTD), located next to its ATP-binding site, whose function in vivo is still poorly understood. The CTD is comprised of an alpha helix followed by an acidic region (AR) and a C-terminal extension termed the C-tail. Recent biochemical studies on bovine papillomavirus 1 (BPV1) E1 showed that the AR and C-tail regulate the oligomerization of the protein into a double hexamer at the origin. In this study, we assessed the importance of the CTD of human papillomavirus 11 (HPV11) E1 in vivo, using a cell-based DNA replication assay. Our results indicate that combined deletion of the AR and C-tail drastically reduces DNA replication, by 85%, and that further truncation into the alpha-helical region compromises the structural integrity of the E1 helicase domain and its interaction with E2. Surprisingly, removal of the C-tail alone or mutation of highly conserved residues within the domain still allows significant levels of DNA replication (55%). This is in contrast to the absolute requirement for the C-tail reported for BPV1 E1 in vitro and confirmed here in vivo. Characterization of chimeric proteins in which the AR and C-tail from HPV11 E1 were replaced by those of BPV1 indicated that while the function of the AR is transferable, that of the C-tail is not. Collectively, these findings define the contribution of the three CTD subdomains to the DNA replication activity of E1 in vivo and suggest that the function of the C-tail has evolved in a PV type-specific manner. While much is known about hexameric DNA helicases from superfamily 3, the papillomavirus E1 helicase contains a unique C-terminal domain (CTD) adjacent to its ATP-binding site. We show here that this CTD is important for the DNA replication activity of HPV11 E1 in vivo and that it can be divided into three functional subdomains that roughly correspond to the three conserved regions of the CTD: an alpha helix, needed for the structural

Requirement for the E1 Helicase C-Terminal Domain in Papillomavirus DNA Replication In Vivo

Science.gov (United States)

Bergvall, Monika; Gagnon, David; Titolo, Steve; Lehoux, Michaël; D'Abramo, Claudia M.

2016-01-01

ABSTRACT The papillomavirus (PV) E1 helicase contains a conserved C-terminal domain (CTD), located next to its ATP-binding site, whose function in vivo is still poorly understood. The CTD is comprised of an alpha helix followed by an acidic region (AR) and a C-terminal extension termed the C-tail. Recent biochemical studies on bovine papillomavirus 1 (BPV1) E1 showed that the AR and C-tail regulate the oligomerization of the protein into a double hexamer at the origin. In this study, we assessed the importance of the CTD of human papillomavirus 11 (HPV11) E1 in vivo, using a cell-based DNA replication assay. Our results indicate that combined deletion of the AR and C-tail drastically reduces DNA replication, by 85%, and that further truncation into the alpha-helical region compromises the structural integrity of the E1 helicase domain and its interaction with E2. Surprisingly, removal of the C-tail alone or mutation of highly conserved residues within the domain still allows significant levels of DNA replication (55%). This is in contrast to the absolute requirement for the C-tail reported for BPV1 E1 in vitro and confirmed here in vivo. Characterization of chimeric proteins in which the AR and C-tail from HPV11 E1 were replaced by those of BPV1 indicated that while the function of the AR is transferable, that of the C-tail is not. Collectively, these findings define the contribution of the three CTD subdomains to the DNA replication activity of E1 in vivo and suggest that the function of the C-tail has evolved in a PV type-specific manner. IMPORTANCE While much is known about hexameric DNA helicases from superfamily 3, the papillomavirus E1 helicase contains a unique C-terminal domain (CTD) adjacent to its ATP-binding site. We show here that this CTD is important for the DNA replication activity of HPV11 E1 in vivo and that it can be divided into three functional subdomains that roughly correspond to the three conserved regions of the CTD: an alpha helix, needed

Lopinavir up-regulates expression of the antiviral protein ribonuclease L in human papillomavirus-positive cervical carcinoma cells.

Science.gov (United States)

Batman, Gavin; Oliver, Anthony W; Zehbe, Ingeborg; Richard, Christina; Hampson, Lynne; Hampson, Ian N

2011-01-01

We have previously shown that the HIV protease inhibitor lopinavir has selective toxicity against human papillomavirus (HPV)-positive cervical carcinoma cells via an unknown mechanism. SiHa cervical carcinoma cells were stably transfected with the proteasome sensor vector pZsProSensor-1 to confirm lopinavir inhibits the proteasome in these cells. The Panorama Xpress profiler 725 antibody array was then used to analyse specific changes in protein expression in lopinavir-treated versus control untreated SiHa cells followed by PCR and western blotting. Colorimetric growth assays of lopinavir-treated E6/E7 immortalised versus control human keratinocytes were performed. Targeted small interfering RNA gene silencing followed by growth assay comparison of lopinavir-treated/untreated SiHa cells was also used. Lopinavir induced an increase in the fluorescence of pZsProSensor-1 transfected SiHa cells, indicative of proteasomal inhibition. Ribonuclease L (RNASEL) protein was shown to be up-regulated in lopinavir-treated SiHa cells, which was confirmed by PCR and western blot. Targeted silencing of RNASEL reduced the sensitivity of SiHa cells to lopinavir. Selective toxicity against E6/E7 immortalised keratinocytes versus control cells was also seen with lopinavir and was associated with up-regulated RNASEL expression. These data are consistent with the toxicity of lopinavir against HPV-positive cervical carcinoma cells being related to its ability to block viral proteasome activation and induce an up-regulation of the antiviral protein RNASEL. This is supported by the drug's selective toxicity and up-regulation of RNASEL in E6/E7 immortalised keratinocytes combined with the increased resistance to lopinavir observed in SiHa cells following silencing of RNASEL gene expression.

Single-tube multiplex PCR using type-specific E6/E7 primers and capillary electrophoresis genotypes 21 human papillomaviruses in neoplasia

Directory of Open Access Journals (Sweden)

Warenholt Janina

2011-01-01

Full Text Available Abstract Background Human papillomavirus (HPV E6/E7 type-specific oncogenes are required for cervical carcinogenesis. Current PCR protocols for genotyping high-risk HPV in cervical screening are not standardized and usually use consensus primers targeting HPV capsid genes, which are often deleted in neoplasia. PCR fragments are detected using specialized equipment and extra steps, including probe hybridization or primer extension. In published papers, analytical sensitivity is typically compared with a different protocol on the same sample set. A single-tube multiplex PCR containing type-specific primers was developed to target the E6/E7 genes of two low-risk and 19 high-risk genotypes (HPV6, 11 and 16, 18, 26, 31, 33, 35, 39, 45, 51, 52, 53, 56, 58, 59, 66, 68, 70, 73 and 82 and the resulting short fragments were directly genotyped by high-resolution fluorescence capillary electrophoresis. Results The method was validated using long oligonucleotide templates, plasmid clones and 207 clinical samples of DNA from liquid-based cytology, fresh and formalin-fixed specimens and FTA Microcards® imprinted with cut tumor surfaces, swabbed cervical cancers or ejected aspirates from nodal metastases of head and neck carcinomas. Between one and five long oligonucleotide targets per sample were detected without false calls. Each of the 21 genotypes was detected in the clinical sample set with up to five types simultaneously detected in individual specimens. All 101 significant cervical neoplasias (CIN 2 and above, except one adenocarcinoma, contained E6/E7 genes. The resulting genotype distribution accorded with the national pattern with HPV16 and 18 accounting for 69% of tumors. Rare HPV types 70 and 73 were present as the sole genotype in one carcinoma each. One cervical SCC contained DNA from HPV6 and 11 only. Six of twelve oropharyngeal cancer metastases and three neck metastases of unknown origin bore E6/E7 DNA; all but one were HPV16. One neck

Prevention of carcinoma of cervix with human papillomavirus vaccine.

Science.gov (United States)

Gavarasana, S; Kalasapudi, R S; Rao, T D; Thirumala, S

2000-01-01

Carcinoma of cervix is the most common cancer found among the women of India. Though cervical cytology screening was effective in preventing carcinoma of cervix in developed nations, it is considered unsuitable in developing countries. Recent research has established an etiological link between human papillomavirus infection and carcinoma of cervix. In this review, an attempt is made to answer the question, 'whether carcinoma of cervix can be prevented with human papillomavirus vaccine?' Literature search using Pubmed and Medline was carried out and relevant articles were reviewed. There is ample experimental evidence to show that DNA of human papillomavirus integrates with cervical cell genome. Viral genes E6 and E7 of HPV type 16 and 18 inactivate p53 function and Rb gene, thus immortalize the cervical epithelial cells. Recombinant vaccines blocked the function of E6 and E7 genes preventing development of papillomas in animals. Vaccination with HPV-VLPs encoding for genes of E6 and E7 neutralizes HPV integrated genome of malignant cells of uterine cervix. Based on experimental evidence, it is possible to prevent carcinoma of cervix with human papillomavirus vaccine, Further research is necessary to identify a effective and safe HPV vaccine, routes of administration and characteristics of potential beneficiaries.

Optimization of heterologous DNA-prime, protein boost regimens and site of vaccination to enhance therapeutic immunity against human papillomavirus-associated disease.

Science.gov (United States)

Peng, Shiwen; Qiu, Jin; Yang, Andrew; Yang, Benjamin; Jeang, Jessica; Wang, Joshua W; Chang, Yung-Nien; Brayton, Cory; Roden, Richard B S; Hung, Chien-Fu; Wu, T-C

2016-01-01

Human papillomavirus (HPV) has been identified as the primary etiologic factor of cervical cancer as well as subsets of anogenital and oropharyngeal cancers. The two HPV viral oncoproteins, E6 and E7, are uniquely and consistently expressed in all HPV infected cells and are therefore promising targets for therapeutic vaccination. Both recombinant naked DNA and protein-based HPV vaccines have been demonstrated to elicit HPV-specific CD8+ T cell responses that provide therapeutic effects against HPV-associated tumor models. Here we examine the immunogenicity in a preclinical model of priming with HPV DNA vaccine followed by boosting with filterable aggregates of HPV 16 L2E6E7 fusion protein (TA-CIN). We observed that priming twice with an HPV DNA vaccine followed by a single TA-CIN booster immunization generated the strongest antigen-specific CD8+ T cell response compared to other prime-boost combinations tested in C57BL/6 mice, whether naïve or bearing the HPV16 E6/E7 transformed syngeneic tumor model, TC-1. We showed that the magnitude of antigen-specific CD8+ T cell response generated by the DNA vaccine prime, TA-CIN protein vaccine boost combinatorial strategy is dependent on the dose of TA-CIN protein vaccine. In addition, we found that a single booster immunization comprising intradermal or intramuscular administration of TA-CIN after priming twice with an HPV DNA vaccine generated a comparable boost to E7-specific CD8+ T cell responses. We also demonstrated that the immune responses elicited by the DNA vaccine prime, TA-CIN protein vaccine boost strategy translate into potent prophylactic and therapeutic antitumor effects. Finally, as seen for repeat TA-CIN protein vaccination, we showed that the heterologous DNA prime and protein boost vaccination strategy is well tolerated by mice. Our results provide rationale for future clinical testing of HPV DNA vaccine prime, TA-CIN protein vaccine boost immunization regimen for the control of HPV-associated diseases.

Intracellular human papillomavirus E6, E7 mRNA quantification predicts CIN 2+ in cervical biopsies better than Papanicolaou screening for women regardless of age.

Science.gov (United States)

Pierry, Deirdre; Weiss, Gerald; Lack, Benjamin; Chen, Victor; Fusco, Judy

2012-08-01

Cervical cancer screening in women younger than 30 years relies on cervical cytology because of the poor performance of human papillomavirus (HPV) DNA testing in this age group. To determine the performance of in-cell HPV E6, E7 mRNA quantification (HPV OncoTect) for the detection of high-grade cervical intraepithelial neoplasia in women younger than 30 years. We analyzed 3133 cytology specimens from a screening population of women aged 19-75 years investigate HPV OncoTect as a triage/secondary screening test for atypical squamous cells of undetermined significance (ASCUS) and low-grade squamous intraepithelial lesion (LSIL) cytology in women younger than 30 years. Test results were compared to histology in 246 cases. The sensitivity of E6, E7 mRNA was 89% for CIN 2+ and 100% for CIN 3+ lesions in women 30 years and older. In women younger than 30 years, the sensitivity of E6, E7 mRNA for CIN 2+ lesions was 88% for CIN 2+ and 92% for CIN 3+ lesions. Abnormal cytology (≥ASCUS) exhibited a sensitivity of 89% for CIN 2+ and 100% for CIN 3+ in women 30 years and older and 96% sensitivity for CIN 2+ and 93% sensitivity for CIN 3+ in women younger than 30. The specificity of E6, E7 mRNA was >80% for CIN 2+ and CIN 3+ in both groups of women compared to a specificity of abnormal cytology of ASCUS/LSIL triage in women including those younger than 30 years.

L2, the minor capsid protein of papillomavirus

Energy Technology Data Exchange (ETDEWEB)

Wang, Joshua W. [Department of Pathology, The Johns Hopkins University, Baltimore, MD 21287 (United States); Roden, Richard B.S., E-mail: roden@jhmi.edu [Department of Pathology, The Johns Hopkins University, Baltimore, MD 21287 (United States); Department of Oncology, The Johns Hopkins University, Baltimore, MD 21287 (United States); Department of Gynecology and Obstetrics, The Johns Hopkins University, Baltimore, MD 21287 (United States)

2013-10-15

The capsid protein L2 plays major roles in both papillomavirus assembly and the infectious process. While L1 forms the majority of the capsid and can self-assemble into empty virus-like particles (VLPs), L2 is a minor capsid component and lacks the capacity to form VLPs. However, L2 co-assembles with L1 into VLPs, enhancing their assembly. L2 also facilitates encapsidation of the ∼8 kbp circular and nucleosome-bound viral genome during assembly of the non-enveloped T=7d virions in the nucleus of terminally differentiated epithelial cells, although, like L1, L2 is not detectably expressed in infected basal cells. With respect to infection, L2 is not required for particles to bind to and enter cells. However L2 must be cleaved by furin for endosome escape. L2 then travels with the viral genome to the nucleus, wherein it accumulates at ND-10 domains. Here, we provide an overview of the biology of L2. - Highlights: • L2 is the minor antigen of the non-enveloped T=7d icosahedral Papillomavirus capsid. • L2 is a nuclear protein that can traffic to ND-10 and facilitate genome encapsidation. • L2 is critical for infection and must be cleaved by furin. • L2 is a broadly protective vaccine antigen recognized by neutralizing antibodies.

L2, the minor capsid protein of papillomavirus

International Nuclear Information System (INIS)

Wang, Joshua W.; Roden, Richard B.S.

2013-01-01

The capsid protein L2 plays major roles in both papillomavirus assembly and the infectious process. While L1 forms the majority of the capsid and can self-assemble into empty virus-like particles (VLPs), L2 is a minor capsid component and lacks the capacity to form VLPs. However, L2 co-assembles with L1 into VLPs, enhancing their assembly. L2 also facilitates encapsidation of the ∼8 kbp circular and nucleosome-bound viral genome during assembly of the non-enveloped T=7d virions in the nucleus of terminally differentiated epithelial cells, although, like L1, L2 is not detectably expressed in infected basal cells. With respect to infection, L2 is not required for particles to bind to and enter cells. However L2 must be cleaved by furin for endosome escape. L2 then travels with the viral genome to the nucleus, wherein it accumulates at ND-10 domains. Here, we provide an overview of the biology of L2. - Highlights: • L2 is the minor antigen of the non-enveloped T=7d icosahedral Papillomavirus capsid. • L2 is a nuclear protein that can traffic to ND-10 and facilitate genome encapsidation. • L2 is critical for infection and must be cleaved by furin. • L2 is a broadly protective vaccine antigen recognized by neutralizing antibodies

The E5 protein of human papillomavirus type 16 perturbs MHC class II antigen maturation in human foreskin keratinocytes treated with interferon-γ

International Nuclear Information System (INIS)

Zhang Benyue; Li Ping; Wang Exing; Brahmi, Zacharie; Dunn, Kenneth W.; Blum, Janice S.; Roman, Ann

2003-01-01

Major histocompatibility complex (MHC) class II antigens are expressed on human foreskin keratinocytes (HFKs) following exposure to interferon gamma. The expression of MHC class II proteins on the cell surface may allow keratinocytes to function as antigen-presenting cells and induce a subsequent immune response to virus infection. Invariant chain (Ii) is a chaperone protein which plays an important role in the maturation of MHC class II molecules. The sequential degradation of Ii within acidic endocytic compartments is a key process required for the successful loading of antigenic peptide onto MHC class II molecules. Since human papillomavirus (HPV) 16 E5 can inhibit the acidification of late endosomes in HFKs, the E5 protein may be able to affect proper peptide loading onto the MHC class II molecule. To test this hypothesis, HFKs were infected with either control virus or a recombinant virus expressing HPV16 E5 and the infected cells were subsequently treated with interferon-γ. ELISAs revealed a decrease of MHC class II expression on the surface of E5-expressing cells compared with control virus-infected cells after interferon treatment. Western blot analysis showed that, in cells treated with interferon gamma, E5 could prevent the breakdown of Ii and block the formation of peptide-loaded, SDS-stable mature MHC class II dimers, correlating with diminished surface MHC class II expression. These data suggest that HPV16 E5 may be able to decrease immune recognition of infected keratinocytes via disruption of MHC class II protein function

MVA E2 recombinant vaccine in the treatment of human papillomavirus infection in men presenting intraurethral flat condyloma: a phase I/II study.

Science.gov (United States)

Albarran Y Carvajal, Antonio; de la Garza, Alfonso; Cruz Quiroz, Benitez Jose Cecilio; Vazquez Zea, Eduardo; Díaz Estrada, Ismael; Mendez Fuentez, Ernesto; López Contreras, Mario; Andrade-Manzano, Alejandro; Padilla, Santiago; Varela, Axel Ramírez; Rosales, Ricardo

2007-01-01

Human papillomavirus (HPV) is the etiologic agent for warts and cervical cancer. In Mexico, the death rate from cervical cancer is extremely high, and statistical data show that since 1990 the number of deaths is increasing. Condylomas and cancer of the penis are the most common lesions presented in men; bladder and prostate cancer in men are also associated with the presence of HPV. Since HPV is transmitted by sexual intercourse, treating both partners is necessary in order to eliminate the virus in the population. Approaches to this include preventative vaccines such as Gardasil, and therapeutic vaccines to treat established infections in both men and women. This will be the only way to decrease the numbers of deaths due to this malignancy. We conducted a phase I/II clinical trial to evaluate the potential use of the recombinant vaccinia viral vaccine MVA E2 (composed of modified vaccinia virus Ankara [MVA] expressing the E2 gene of bovine papillomavirus) to treat flat condyloma lesions associated with oncogenic HPV in men. Fifty male patients with flat condyloma lesions were treated with either MVA E2 therapeutic vaccine or fluorouracil (5-fluorouracil). Thirty men received the therapeutic vaccine, at a total of 10(6) virus particles per dose, administered directly into the urethra once every week over a 4-week period. Twenty control patients were treated with 5% fluorouracil 1mL twice weekly over a 4-week period directly into the urethra. Reduction of lesions or absence of papillomavirus infection was monitored by colposcopy and histologic analysis. The immune response after MVA E2 treatment was determined by measuring the antibodies against the MVA E2 virus and by analyzing the lymphocyte cytotoxic activity against cancer cells bearing oncogenic papillomavirus. Presence of papillomavirus was determined by the Hybrid Capture method. Twenty-eight of 30 patients showed no lesion or presence of papillomavirus as diagnosed by colposcopy and brush histologic

The E4 protein; structure, function and patterns of expression

Energy Technology Data Exchange (ETDEWEB)

Doorbar, John, E-mail: jdoorba@nimr.mrc.ac.uk

2013-10-15

The papillomavirus E4 open reading frame (ORF) is contained within the E2 ORF, with the primary E4 gene-product (E1{sup ∧}E4) being translated from a spliced mRNA that includes the E1 initiation codon and adjacent sequences. E4 is located centrally within the E2 gene, in a region that encodes the E2 protein′s flexible hinge domain. Although a number of minor E4 transcripts have been reported, it is the product of the abundant E1{sup ∧}E4 mRNA that has been most extensively analysed. During the papillomavirus life cycle, the E1{sup ∧}E4 gene products generally become detectable at the onset of vegetative viral genome amplification as the late stages of infection begin. E4 contributes to genome amplification success and virus synthesis, with its high level of expression suggesting additional roles in virus release and/or transmission. In general, E4 is easily visualised in biopsy material by immunostaining, and can be detected in lesions caused by diverse papillomavirus types, including those of dogs, rabbits and cattle as well as humans. The E4 protein can serve as a biomarker of active virus infection, and in the case of high-risk human types also disease severity. In some cutaneous lesions, E4 can be expressed at higher levels than the virion coat proteins, and can account for as much as 30% of total lesional protein content. The E4 proteins of the Beta, Gamma and Mu HPV types assemble into distinctive cytoplasmic, and sometimes nuclear, inclusion granules. In general, the E4 proteins are expressed before L2 and L1, with their structure and function being modified, first by kinases as the infected cell progresses through the S and G2 cell cycle phases, but also by proteases as the cell exits the cell cycle and undergoes true terminal differentiation. The kinases that regulate E4 also affect other viral proteins simultaneously, and include protein kinase A, Cyclin-dependent kinase, members of the MAP Kinase family and protein kinase C. For HPV16 E1{sup ∧}E

Molecular cloning and characterisation of a novel type of human papillomavirus 160 isolated from a flat wart of an immunocompetent patient.

Directory of Open Access Journals (Sweden)

Tsuyoshi Mitsuishi

Full Text Available More than 150 types of Human papillomaviruses (HPVs have been isolated from numerous cutaneous and/or mucosal lesions. Flat wart samples on the face from 36 immunocompetent patients were collected and screened for HPV. From one sample, we cloned a putative novel genotype. The novel type consisted of 7779 bp in length with a GC content of 47.1%, containing open reading frames for putative early proteins (E1, E2, E4, E6, and E7 and two late proteins (L1 and L2. Homology searches and phylogenetic analyses indicated that it belonged to Alphapapillomavirus (Alpha-PV species 2 and most closely resembled HPV 3. The virus fulfilled the definition of a novel type, and was named HPV 160 by the Reference Center for Papillomaviruses. The putative E7 protein of HPV 160 as well as HPV 29, 77, and 78 contained the Leu-X-Cys-X-Glu pRB-binding motif but other Alpha-PV species 2 (HPV 3, 10, 28, 94, 117, and 125 did not have this conserved motif.

Large scale genotype comparison of human papillomavirus E2-host interaction networks provides new insights for e2 molecular functions.

Science.gov (United States)

Muller, Mandy; Jacob, Yves; Jones, Louis; Weiss, Amélie; Brino, Laurent; Chantier, Thibault; Lotteau, Vincent; Favre, Michel; Demeret, Caroline

2012-01-01

Human Papillomaviruses (HPV) cause widespread infections in humans, resulting in latent infections or diseases ranging from benign hyperplasia to cancers. HPV-induced pathologies result from complex interplays between viral proteins and the host proteome. Given the major public health concern due to HPV-associated cancers, most studies have focused on the early proteins expressed by HPV genotypes with high oncogenic potential (designated high-risk HPV or HR-HPV). To advance the global understanding of HPV pathogenesis, we mapped the virus/host interaction networks of the E2 regulatory protein from 12 genotypes representative of the range of HPV pathogenicity. Large-scale identification of E2-interaction partners was performed by yeast two-hybrid screenings of a HaCaT cDNA library. Based on a high-confidence scoring scheme, a subset of these partners was then validated for pair-wise interaction in mammalian cells with the whole range of the 12 E2 proteins, allowing a comparative interaction analysis. Hierarchical clustering of E2-host interaction profiles mostly recapitulated HPV phylogeny and provides clues to the involvement of E2 in HPV infection. A set of cellular proteins could thus be identified discriminating, among the mucosal HPV, E2 proteins of HR-HPV 16 or 18 from the non-oncogenic genital HPV. The study of the interaction networks revealed a preferential hijacking of highly connected cellular proteins and the targeting of several functional families. These include transcription regulation, regulation of apoptosis, RNA processing, ubiquitination and intracellular trafficking. The present work provides an overview of E2 biological functions across multiple HPV genotypes.

Analysis of cis-elements that facilitate extrachromosomal persistence of human papillomavirus genomes

International Nuclear Information System (INIS)

Pittayakhajonwut, Daraporn; Angeletti, Peter C.

2008-01-01

Human papillomaviruses (HPVs) are maintained latently in dividing epithelial cells as nuclear plasmids. Two virally encoded proteins, E1, a helicase, and E2, a transcription factor, are important players in replication and stable plasmid maintenance in host cells. Recent experiments in yeast have demonstrated that viral genomes retain replication and maintenance function independently of E1 and E2 [Angeletti, P.C., Kim, K., Fernandes, F.J., and Lambert, P.F. (2002). Stable replication of papillomavirus genomes in Saccharomyces cerevisiae. J. Virol. 76(7), 3350-8; Kim, K., Angeletti, P.C., Hassebroek, E.C., and Lambert, P.F. (2005). Identification of cis-acting elements that mediate the replication and maintenance of human papillomavirus type 16 genomes in Saccharomyces cerevisiae. J. Virol. 79(10), 5933-42]. Flow cytometry studies of EGFP-reporter vectors containing subgenomic HPV fragments with or without a human ARS (hARS), revealed that six fragments located in E6-E7, E1-E2, L1, and L2 regions showed a capacity for plasmid stabilization in the absence of E1 and E2 proteins. Interestingly, four fragments within E7, the 3' end of L2, and the 5' end of L1 exhibited stability in plasmids that lacked an hARS, indicating that they possess both replication and maintenance functions. Two fragments lying in E1-E2 and the 3' region of L1 were stable only in the presence of hARS, that they contained only maintenance function. Mutational analyses of HPV16-GFP reporter constructs provided evidence that genomes lacking E1 and E2 could replicate to an extent similar to wild type HPV16. Together these results support the concept that cellular factors influence HPV replication and maintenance, independently, and perhaps in conjunction with E1 and E2, suggesting a role in the persistent phase of the viral lifecycle

Association of antibody to E2 protein of human papillomavirus and p16INK4A with progression of HPV-infected cervical lesions.

Science.gov (United States)

Chuerduangphui, Jureeporn; Pientong, Chamsai; Swangphon, Piyawut; Luanratanakorn, Sanguanchoke; Sangkomkamhang, Ussanee; Tungsiriwattana, Thumwadee; Kleebkaow, Pilaiwan; Burassakarn, Ati; Ekalaksananan, Tipaya

2018-05-09

Human papillomavirus (HPV) E2 and L1 proteins are expressed in cervical cells during the lytic stage of infection. Overexpression of p16 INK4A is a biomarker of HPV-associated cervical neoplasia. This study investigated antibodies to HPV16 E2, HPV16 L1, and p16 INK4A in sera from women with no squamous intraepithelial lesion (No-SIL) of the cervix, low-grade SIL, high-grade SIL, and cervical squamous cell carcinoma (SCC). HPV DNA was detected by polymerase chain reaction. Anti-E2, -L1, and -p16 INK4A antibodies in sera were determined by western blot. Among 116 samples, 69 (60%) were HPV DNA-positive. Percentages seropositive for anti-E2, -L1, and -p16 INK4A antibodies were 39.6, 22.4, and 23.3%, respectively. Anti-E2 antibody was significantly correlated with HPV DNA-positive cases. Eighty-seven women (75%) were regarded as infected with HPV, having at least one positive result from HPV DNA, L1, or E2 antibody. Antibody to p16 INK4A was associated with HPV infection (odds = 5.444, 95% CI 1.203-24.629, P = 0.028) and precancerous cervical lesions (odds = 5.132, 95% CI 1.604-16.415, P = 0.006). Interestingly, the concurrent detection of anti-E2 and -p16 INK4A antibodies was significantly associated with HPV infection (odds = 1.382, 95% CI 1.228-1.555, P = 0.044). These antibodies might be good candidate biomarkers for monitoring HPV-associated cervical lesion development to cancer.

Transcriptional regulatory elements in the noncoding region of human papillomavirus type 6

International Nuclear Information System (INIS)

Wu, Tzyy-Choou.

1989-01-01

The structure and function of the transcriptional regulatory region of human papillomavirus type 6 (HPV-6) has been investigated. To investigate tissue specific gene expression, a sensitive method to detect and localize HPV-6 viral DNA, mRNA and protein in plastic-embedded tissue sections of genital and respiratory tract papillomata by using in situ hybridization and immunoperoxidase assays has been developed. This method, using ultrathin sections and strand-specific 3 H labeled riboprobes, offers the advantages of superior morphological preservation and detection of viral genomes at low copy number with good resolution, and the modified immunocytochemistry provides better sensitivity. The results suggest that genital tract epithelium is more permissive for HPV-6 replication than respiratory tract epithelium. To study the tissue tropism of HPV-6 at the level of regulation of viral gene expression, the polymerase chain reaction was used to isolate the noncoding region (NCR) of HPV-6 in independent isolates. Nucleotide sequence analysis of molecularly cloned DNA identified base substitutions, deletions/insertions and tandem duplications. Transcriptional regulatory elements in the NCR were assayed in recombinant plasmids containing the bacterial gene for chloramphenicol acetyl transferase

Large scale genotype comparison of human papillomavirus E2-host interaction networks provides new insights for e2 molecular functions.

Directory of Open Access Journals (Sweden)

Mandy Muller

Full Text Available Human Papillomaviruses (HPV cause widespread infections in humans, resulting in latent infections or diseases ranging from benign hyperplasia to cancers. HPV-induced pathologies result from complex interplays between viral proteins and the host proteome. Given the major public health concern due to HPV-associated cancers, most studies have focused on the early proteins expressed by HPV genotypes with high oncogenic potential (designated high-risk HPV or HR-HPV. To advance the global understanding of HPV pathogenesis, we mapped the virus/host interaction networks of the E2 regulatory protein from 12 genotypes representative of the range of HPV pathogenicity. Large-scale identification of E2-interaction partners was performed by yeast two-hybrid screenings of a HaCaT cDNA library. Based on a high-confidence scoring scheme, a subset of these partners was then validated for pair-wise interaction in mammalian cells with the whole range of the 12 E2 proteins, allowing a comparative interaction analysis. Hierarchical clustering of E2-host interaction profiles mostly recapitulated HPV phylogeny and provides clues to the involvement of E2 in HPV infection. A set of cellular proteins could thus be identified discriminating, among the mucosal HPV, E2 proteins of HR-HPV 16 or 18 from the non-oncogenic genital HPV. The study of the interaction networks revealed a preferential hijacking of highly connected cellular proteins and the targeting of several functional families. These include transcription regulation, regulation of apoptosis, RNA processing, ubiquitination and intracellular trafficking. The present work provides an overview of E2 biological functions across multiple HPV genotypes.

Calcein represses human papillomavirus 16 E1-E2 mediated DNA replication via blocking their binding to the viral origin of replication.

Science.gov (United States)

Das, Dipon; Smith, Nathan W; Wang, Xu; Richardson, Stacie L; Hartman, Matthew C T; Morgan, Iain M

2017-08-01

Human papillomaviruses are causative agents in several human diseases ranging from genital warts to ano-genital and oropharyngeal cancers. Currently only symptoms of HPV induced disease are treated; there are no antivirals available that directly target the viral life cycle. Previously, we determined that the cellular protein TopBP1 interacts with the HPV16 replication/transcription factor E2. This E2-TopBP1 interaction is essential for optimal E1-E2 DNA replication and for the viral life cycle. The drug calcein disrupts the interaction of TopBP1 with itself and other host proteins to promote cell death. Here we demonstrate that calcein blocks HPV16 E1-E2 DNA replication via blocking the viral replication complex forming at the origin of replication. This occurs at non-toxic levels of calcein and demonstrates specificity as it does not block the ability of E2 to regulate transcription. We propose that calcein or derivatives could be developed as an anti-HPV therapeutic. Copyright © 2017 Elsevier Inc. All rights reserved.

Papillomavirus E2 induces senescence in HPV-positive cells via pRB- and p21CIP-dependent pathways

OpenAIRE

Wells, Susanne I.; Francis, Delicia A.; Karpova, Alla Y.; Dowhanick, Jennifer J.; Benson, John D.; Howley, Peter M.

2000-01-01

A hallmark of human papillomavirus (HPV) associated carcinogenesis is the integration of the viral DNA into the cellular genome, usually accompanied by the loss of expression of the viral E2 gene. E2 binds to and represses the viral promoter directing expression of the E6 and E7 oncogenes. The re-introduction and expression of exogenous E2 in HPV-positive cancer cells results in cellular growth arrest, while growth in the context of exogenous E2 can be restored through the expression of exoge...

Modulation of microRNA-mRNA Target Pairs by Human Papillomavirus 16 Oncoproteins

Directory of Open Access Journals (Sweden)

Mallory E. Harden

2017-01-01

Full Text Available The E6 and E7 proteins are the major oncogenic drivers encoded by high-risk human papillomaviruses (HPVs. While many aspects of the transforming activities of these proteins have been extensively studied, there are fewer studies that have investigated how HPV E6/E7 expression affects the expression of cellular noncoding RNAs. The goal of our study was to investigate HPV16 E6/E7 modulation of cellular microRNA (miR levels and to determine the potential consequences for cellular gene expression. We performed deep sequencing of small and large cellular RNAs in primary undifferentiated cultures of human foreskin keratinocytes (HFKs with stable expression of HPV16 E6/E7 or a control vector. After integration of the two data sets, we identified 51 differentially expressed cellular miRs associated with the modulation of 1,456 potential target mRNAs in HPV16 E6/E7-expressing HFKs. We discovered that the degree of differential miR expression in HFKs expressing HPV16 E6/E7 was not necessarily predictive of the number of corresponding mRNA targets or the potential impact on gene expression. Additional analyses of the identified miR-mRNA pairs suggest modulation of specific biological activities and biochemical pathways. Overall, our study supports the model that perturbation of cellular miR expression by HPV16 E6/E7 importantly contributes to the rewiring of cellular regulatory circuits by the high-risk HPV E6 and E7 proteins that contribute to oncogenic transformation.

Expression of CPEB, GAPDH and U6snRNA in cervical and ovarian tissue during cancer development

DEFF Research Database (Denmark)

Hansen, Christina Neigaard; Ketabi, Zohreh; Rosenstierne, Maiken Worsøe

2009-01-01

Persistent infection with high-risk human papillomavirus (HPV) and expression of the proteins E6 and E7 is a prerequisite for development of cervical cancer. The distal non-coding part of E6/E7 messengers from several HPV types is able to downregulate synthesis of a reporter gene through mechanisms...

Systemic Immunization with Papillomavirus L1 Protein Completely Prevents the Development of Viral Mucosal Papillomas

Science.gov (United States)

Suzich, Joann A.; Ghim, Shin-Je; Palmer-Hill, Frances J.; White, Wendy I.; Tamura, James K.; Bell, Judith A.; Newsome, Joseph A.; Bennett Jenson, A.; Schlegel, Richard

1995-12-01

Infection of mucosal epithelium by papillomaviruses is responsible for the induction of genital and oral warts and plays a critical role in the development of human cervical and oropharyngeal cancer. We have employed a canine model to develop a systemic vaccine that completely protects against experimentally induced oral mucosal papillomas. The major capsid protein, L1, of canine oral papillomavirus (COPV) was expressed in Sf9 insect cells in native conformation. L1 protein, which self-assembled into virus-like particles, was purified on CsCl gradients and injected intradermally into the foot pad of beagles. Vaccinated animals developed circulating antibodies against COPV and became completely resistant to experimental challenge with COPV. Successful immunization was strictly dependent upon native L1 protein conformation and L1 type. Partial protection was achieved with as little as 0.125 ng of L1 protein, and adjuvants appeared useful for prolonging the host immune response. Serum immunoglobulins passively transferred from COPV L1-immunized beagles to naive beagles conferred protection from experimental infection with COPV. Our results indicate the feasibility of developing a human vaccine to prevent mucosal papillomas, which can progress to malignancy.

Evidence supporting a role for TopBP1 and Brd4 in the initiation but not continuation of human papillomavirus 16 E1/E2-mediated DNA replication.

Science.gov (United States)

Gauson, Elaine J; Donaldson, Mary M; Dornan, Edward S; Wang, Xu; Bristol, Molly; Bodily, Jason M; Morgan, Iain M

2015-05-01

To replicate the double-stranded human papillomavirus 16 (HPV16) DNA genome, viral proteins E1 and E2 associate with the viral origin of replication, and E2 can also regulate transcription from adjacent promoters. E2 interacts with host proteins in order to regulate both transcription and replication; TopBP1 and Brd4 are cellular proteins that interact with HPV16 E2. Previous work with E2 mutants demonstrated the Brd4 requirement for the transactivation properties of E2, while TopBP1 is required for DNA replication induced by E2 from the viral origin of replication in association with E1. More-recent studies have also implicated Brd4 in the regulation of DNA replication by E2 and E1. Here, we demonstrate that both TopBP1 and Brd4 are present at the viral origin of replication and that interaction with E2 is required for optimal initiation of DNA replication. Both cellular proteins are present in E1-E2-containing nuclear foci, and the viral origin of replication is required for the efficient formation of these foci. Short hairpin RNA (shRNA) against either TopBP1 or Brd4 destroys the E1-E2 nuclear bodies but has no effect on E1-E2-mediated levels of DNA replication. An E2 mutation in the context of the complete HPV16 genome that compromises Brd4 interaction fails to efficiently establish episomes in primary human keratinocytes. Overall, the results suggest that interactions between TopBP1 and E2 and between Brd4 and E2 are required to correctly initiate DNA replication but are not required for continuing DNA replication, which may be mediated by alternative processes such as rolling circle amplification and/or homologous recombination. Human papillomavirus 16 (HPV16) is causative in many human cancers, including cervical and head and neck cancers, and is responsible for the annual deaths of hundreds of thousands of people worldwide. The current vaccine will save lives in future generations, but antivirals targeting HPV16 are required for the alleviation of disease

Human Papillomaviruses; Epithelial Tropisms, and the Development of Neoplasia

Science.gov (United States)

Egawa, Nagayasu; Egawa, Kiyofumi; Griffin, Heather; Doorbar, John

2015-01-01

Papillomaviruses have evolved over many millions of years to propagate themselves at specific epithelial niches in a range of different host species. This has led to the great diversity of papillomaviruses that now exist, and to the appearance of distinct strategies for epithelial persistence. Many papillomaviruses minimise the risk of immune clearance by causing chronic asymptomatic infections, accompanied by long-term virion-production with only limited viral gene expression. Such lesions are typical of those caused by Beta HPV types in the general population, with viral activity being suppressed by host immunity. A second strategy requires the evolution of sophisticated immune evasion mechanisms, and allows some HPV types to cause prominent and persistent papillomas, even in immune competent individuals. Some Alphapapillomavirus types have evolved this strategy, including those that cause genital warts in young adults or common warts in children. These strategies reflect broad differences in virus protein function as well as differences in patterns of viral gene expression, with genotype-specific associations underlying the recent introduction of DNA testing, and also the introduction of vaccines to protect against cervical cancer. Interestingly, it appears that cellular environment and the site of infection affect viral pathogenicity by modulating viral gene expression. With the high-risk HPV gene products, changes in E6 and E7 expression are thought to account for the development of neoplasias at the endocervix, the anal and cervical transformation zones, and the tonsilar crypts and other oropharyngeal sites. A detailed analysis of site-specific patterns of gene expression and gene function is now prompted. PMID:26193301

Human Papillomaviruses; Epithelial Tropisms, and the Development of Neoplasia

Directory of Open Access Journals (Sweden)

Nagayasu Egawa

2015-07-01

Full Text Available Papillomaviruses have evolved over many millions of years to propagate themselves at specific epithelial niches in a range of different host species. This has led to the great diversity of papillomaviruses that now exist, and to the appearance of distinct strategies for epithelial persistence. Many papillomaviruses minimise the risk of immune clearance by causing chronic asymptomatic infections, accompanied by long-term virion-production with only limited viral gene expression. Such lesions are typical of those caused by Beta HPV types in the general population, with viral activity being suppressed by host immunity. A second strategy requires the evolution of sophisticated immune evasion mechanisms, and allows some HPV types to cause prominent and persistent papillomas, even in immune competent individuals. Some Alphapapillomavirus types have evolved this strategy, including those that cause genital warts in young adults or common warts in children. These strategies reflect broad differences in virus protein function as well as differences in patterns of viral gene expression, with genotype-specific associations underlying the recent introduction of DNA testing, and also the introduction of vaccines to protect against cervical cancer. Interestingly, it appears that cellular environment and the site of infection affect viral pathogenicity by modulating viral gene expression. With the high-risk HPV gene products, changes in E6 and E7 expression are thought to account for the development of neoplasias at the endocervix, the anal and cervical transformation zones, and the tonsilar crypts and other oropharyngeal sites. A detailed analysis of site-specific patterns of gene expression and gene function is now prompted.

The synergistic transactivation of the hepatitis B viral (HBV) pregenomic promoter by the E6 protein of human papillomavirus type 16 (HPV-16 E6) with HBV X protein was mediated through the AP1 site of E element in the enhancer I (EnI) in human liver cell.

Science.gov (United States)

Lee, D H; Choi, B H; Rho, H M

1999-11-01

Infection by HBV of a cell already infected with other viral species or vice versa has been suggested as being involved in hepatocellular carcinoma. Using the CAT assay method, we investigated the interactive roles of HBx and potentially oncogenic and transactivating viral early proteins such as Ad5 E1A, HPV-16 E6, and SV40 T ag. In the presence of HBx, only HPV-16 E6 showed significant synergistic transactivation of EnI. We further investigated the function of the HPV-16 E6 using deletion, heterologous promoter, and mutation analyses on the EnI promoter. The results showed that the synergistic effect was mediated through the AP1 site of the E element in EnI by the direct activation of AP1 and support the idea that the infection by HBV of the cell with other viral species such as HPV-16 could increase the transcription activity of the HBV and other oncogenes containing an AP1 site in the promoter. Copyright 1999 Academic Press.

[Genetics and susceptibility to human papillomaviruses: epidermodysplasia verruciformis, a disease model].

Science.gov (United States)

Orth, Gérard

2010-06-01

The outcomes of infection by human papillomaviruses (HPV), both oncogenic and non oncogenic, show major interindividual variability The underlying genetic factors and mechanisms are poorly known, but their complexity is illustrated by epidermodysplasia verruciformis (EV), a rare autosomal recessive genodermatosis associated with a high risk of non melanoma skin cancer. This model disease is characterized by abnormal susceptibility to widespread betapapillomaviruses, including HPV-5, a virus associated with EV cancers. Most cases of EV are caused by a mutation that inactivates either of two related genes, EVER1 and EVER2. This inactivation likely compensates for the absence of a viral gene (E5 or E8) essential for HPV pathogenicity. Proteins E5 and E8 interfere with the interaction between EVER proteins and ZnT1, a zinc transporter EV is thus likely to represent a primary defect of intrinsic (constitutive) immunity or innate immunity to betapapillomaviruses, involving modulation of zinc homeostasis upon keratinocyte infection. It remains to be established which cellular genes are involved in intrinsic, innate or acquired immune responses to other human papillomaviruses, including oncogenic genital types.

Human papillomavirus 16 E2-, E6- and E7-specific T-cell responses in children and their mothers who developed incident cervical intraepithelial neoplasia during a 14-year follow-up of the Finnish Family HPV cohort.

Science.gov (United States)

Koskimaa, Hanna-Mari; Paaso, Anna E; Welters, Marij J P; Grénman, Seija E; Syrjänen, Kari J; van der Burg, Sjoerd H; Syrjänen, Stina M

2014-02-13

Human papillomavirus (HPV) infection has traditionally been regarded as a sexually transmitted disease (STD), but recent evidence implicates that an infected mother can transmit HPV to her newborn during pregnancy, at delivery, perinatal period or later. Given the lack of any studies on HPV-specific immune responses in children, we conducted HPV16-specific cell-mediated immune (CMI) monitoring of the mother-child pairs with known oral and genital HPV follow-up (FU) data since the delivery. In the Finnish Family HPV Study, 10 out of 331 mothers developed incident cervical intraepithelial neoplasia (CIN) during their 14-year FU. Our hypothesis according to the common dogma is that there is no HPV16 specific immune response in offspring of the CIN mother as she/he has not started the sexual life yet. We used overlapping 30-35 mer peptides covering the entire HPV16 E2, E6 and E7 protein sequences. Assays for lymphocyte proliferation capacity, cytokine production and HPV16-specific Foxp3 + CD25 + CD4+ regulatory T-cells were performed. HPV16-specific proliferative T-cell responses were broader in children than in their mothers. Nine of 10 children had responses against both E2 peptide pools compared to only 4 of the 10 mothers. Six of the 10 children and only 2 mothers displayed reactivity to E6 and/or E7. The cytokine levels of IL-2 (p = 0.023) and IL-5 (p = 0.028) induced by all peptide pools, were also higher among children than their mothers. The children of the mothers with incident CIN3 had significantly higher IFN-γ (p = 0.032) and TNF-α (p = 0.008) levels than other children. Our study is the first to show that also children could have HPV-specific immunity. These data indicate that the children have circulating HPV16-specific memory T-cells which might have been induced by previous HPV16 exposure or ongoing HPV 16 infection.

The PTPN14 Tumor Suppressor Is a Degradation Target of Human Papillomavirus E7.

Science.gov (United States)

Szalmás, Anita; Tomaić, Vjekoslav; Basukala, Om; Massimi, Paola; Mittal, Suruchi; Kónya, József; Banks, Lawrence

2017-04-01

Activation of signaling pathways ensuring cell growth is essential for the proliferative competence of human papillomavirus (HPV)-infected cells. Tyrosine kinases and phosphatases are key regulators of cellular growth control pathways. A recently identified potential cellular target of HPV E7 is the cytoplasmic protein tyrosine phosphatase PTPN14, which is a potential tumor suppressor and is linked to the control of the Hippo and Wnt/beta-catenin signaling pathways. In this study, we show that the E7 proteins of both high-risk and low-risk mucosal HPV types can interact with PTPN14. This interaction is independent of retinoblastoma protein (pRb) and involves residues in the carboxy-terminal region of E7. We also show that high-risk E7 induces proteasome-mediated degradation of PTPN14 in cells derived from cervical tumors. This degradation appears to be independent of cullin-1 or cullin-2 but most likely involves the UBR4/p600 ubiquitin ligase. The degree to which E7 downregulates PTPN14 would suggest that this interaction is important for the viral life cycle and potentially also for the development of malignancy. In support of this we find that overexpression of PTPN14 decreases the ability of HPV-16 E7 to cooperate with activated EJ-ras in primary cell transformation assays. IMPORTANCE This study links HPV E7 to the deregulation of protein tyrosine phosphatase signaling pathways. PTPN14 is classified as a potential tumor suppressor protein, and here we show that it is very susceptible to HPV E7-induced proteasome-mediated degradation. Intriguingly, this appears to use a mechanism that is different from that employed by E7 to target pRb. Therefore, this study has important implications for our understanding of the molecular basis for E7 function and also sheds important light on the potential role of PTPN14 as a tumor suppressor. Copyright © 2017 American Society for Microbiology.

Hepatitis C virus induces E6AP-dependent degradation of the retinoblastoma protein.

Directory of Open Access Journals (Sweden)

Tsubasa Munakata

2007-09-01

Full Text Available Hepatitis C virus (HCV is a positive-strand RNA virus that frequently causes persistent infections and is uniquely associated with the development of hepatocellular carcinoma. While the mechanism(s by which the virus promotes cancer are poorly defined, previous studies indicate that the HCV RNA-dependent RNA polymerase, nonstructural protein 5B (NS5B, forms a complex with the retinoblastoma tumor suppressor protein (pRb, targeting it for degradation, activating E2F-responsive promoters, and stimulating cellular proliferation. Here, we describe the mechanism underlying pRb regulation by HCV and its relevance to HCV infection. We show that the abundance of pRb is strongly downregulated, and its normal nuclear localization altered to include a major cytoplasmic component, following infection of cultured hepatoma cells with either genotype 1a or 2a HCV. We further demonstrate that this is due to NS5B-dependent ubiquitination of pRb and its subsequent degradation via the proteasome. The NS5B-dependent ubiquitination of pRb requires the ubiquitin ligase activity of E6-associated protein (E6AP, as pRb abundance was restored by siRNA knockdown of E6AP or overexpression of a dominant-negative E6AP mutant in cells containing HCV RNA replicons. E6AP also forms a complex with pRb in an NS5B-dependent manner. These findings suggest a novel mechanism for the regulation of pRb in which the HCV NS5B protein traps pRb in the cytoplasm, and subsequently recruits E6AP to this complex in a process that leads to the ubiquitination of pRb. The disruption of pRb/E2F regulatory pathways in cells infected with HCV is likely to promote hepatocellular proliferation and chromosomal instability, factors important for the development of liver cancer.

Identification of a novel human papillomavirus by metagenomic analysis of samples from patients with febrile respiratory illness.

Directory of Open Access Journals (Sweden)

John L Mokili

Full Text Available As part of a virus discovery investigation using a metagenomic approach, a highly divergent novel Human papillomavirus type was identified in pooled convenience nasal/oropharyngeal swab samples collected from patients with febrile respiratory illness. Phylogenetic analysis of the whole genome and the L1 gene reveals that the new HPV identified in this study clusters with previously described gamma papillomaviruses, sharing only 61.1% (whole genome and 63.1% (L1 sequence identity with its closest relative in the Papillomavirus episteme (PAVE database. This new virus was named HPV_SD2 pending official classification. The complete genome of HPV-SD2 is 7,299 bp long (36.3% G/C and contains 7 open reading frames (L2, L1, E6, E7, E1, E2 and E4 and a non-coding long control region (LCR between L1 and E6. The metagenomic procedures, coupled with the bioinformatic methods described herein are well suited to detect small circular genomes such as those of human papillomaviruses.

A novel murine model for evaluating bovine papillomavirus prophylactics/therapeutics for equine sarcoid-like tumours.

Science.gov (United States)

Bogaert, Lies; Woodham, Andrew W; Da Silva, Diane M; Martens, Ann; Meyer, Evelyne; Kast, W Martin

2015-09-01

Equine sarcoids are highly recurrent bovine papillomavirus (BPV)-induced fibroblastic neoplasms that are the most common skin tumours in horses. In order to facilitate the study of potential equine sarcoid prophylactics or therapeutics, which can be a slow and costly process in equines, a murine model for BPV-1 protein-expressing equine sarcoid-like tumours was developed in mice through stable transfection of BPV-1 E5 and E6 in a murine fibroblast tumour cell line (K-BALB). Like equine sarcoids, these murine tumour cells (BPV-KB) were of fibroblast origin, were tumorigenic and expressed BPV-1 proteins. As an initial investigation of the preclinical potential of this tumour model for equine sarcoids prophylactics, mice were immunized with BPV-1 E5E6 Venezuelan equine encephalitis virus replicon particles, prior to BPV-KB challenge, which resulted in an increased tumour-free period compared with controls, indicating that the BPV-KB murine model may be a valuable preclinical alternative to equine clinical trials.

The E7 oncoprotein of high-risk human papillomavirus type 16 enters the nucleus via a nonclassical Ran-dependent pathway

International Nuclear Information System (INIS)

Angeline, Michael; Merle, Eric; Moroianu, Junona

2003-01-01

E7, the major transforming protein of high-risk human papillomavirus (HPV), type 16, binds and inactivates the retinoblastoma protein (pRb), and the Rb-related proteins p107 and p130. HPV16 E7 is a nuclear protein lacking a classical basic nuclear localization signal. In this study we investigated the nuclear import of HPV16 E7 oncoprotein in digitonin-permeabilized HeLa cells. HPV16 E7 nuclear import was independent of pRb, as an E7 ΔDLYC variant defective in pRb binding was imported into the nuclei of digitonin-permeabilized cells as efficiently as wild-type E7 in the presence of exogenous cytosol. Interestingly, we discovered that HPV16 E7 is imported into the nuclei via a novel pathway different from those mediated by Kap α2β1 heterodimers, Kap β1, or Kap β2. Nuclear accumulation of E7 required Ran and was not inhibited by the RanG19V-GTP variant, an inhibitor of Kap β mediated import pathways. Together the data suggest that HPV16 E7 translocates through the nuclear pores via a nonclassical Ran-dependent pathway, independent of the main cytosolic Kap β import receptors

Production of recombinant proteins GST L1, E6 and E7 tag HPV 16 ...

African Journals Online (AJOL)

STORAGESEVER

2009-02-04

Feb 4, 2009 ... targeting the viral oncoproteins E6 and E7 are markers for HPV-associated ... Luminex XYP plate handler, Luminex SD sheath fluid delivery system, a Pentium 4 .... expression mediated by a potato virus X derived vector of the E7 protein .... inflammation, and antioxidant nutrients – assessing their roles as.

HPV8-E6 Interferes with Syntenin-2 Expression through Deregulation of Differentiation, Methylation and Phosphatidylinositide-Kinase Dependent Mechanisms

Directory of Open Access Journals (Sweden)

Benjamin Marx

2017-09-01

Full Text Available The E6 oncoproteins of high-risk human papillomaviruses (HPV of genus alpha contain a short peptide sequence at the carboxy-terminus, the PDZ binding domain, with which they interact with the corresponding PDZ domain of cellular proteins. Interestingly, E6 proteins from papillomaviruses of genus beta (betaPV do not encode a comparable PDZ binding domain. Irrespective of this fact, we previously showed that the E6 protein of HPV8 (betaPV type could circumvent this deficit by targeting the PDZ protein Syntenin-2 through transcriptional repression (Lazic et al., 2012. Despite its high binding affinity to phosphatidylinositol-4,5-bisphosphate (PI(4,5P2, very little is known about Syntenin-2. This study aimed to extend the knowledge on Syntenin-2 and how its expression is controlled. We now identified that Syntenin-2 is expressed at high levels in differentiating and in lower amounts in keratinocytes cultured in serum-free media containing low calcium concentration. HPV8-E6 led to a further reduction of Syntenin-2 expression only in cells cultured in low calcium. In the skin of patients suffering from Epidermodysplasia verruciformis, who are predisposed to betaPV infection, Syntenin-2 was expressed in differentiating keratinocytes of non-lesional skin, but was absent in virus positive squamous tumors. Using 5-Aza-2′-deoxycytidine, which causes DNA demethylation, Syntenin-2 transcription was profoundly activated and fully restored in the absence and presence of HPV8-E6, implicating that E6 mediated repression of Syntenin-2 transcription is due to promoter hypermethylation. Since Syntenin-2 binds to PI(4,5P2, we further tested whether the PI(4,5P2 metabolic pathway might govern Syntenin-2 expression. PI(4,5P2 is generated by the activity of phosphatidylinositol-4-phosphate-5-kinase type I (PIP5KI or phosphatidylinositol-5-phosphate-4-kinase type II (PIP4KII isoforms α, β and γ. Phosphatidylinositide kinases have recently been identified as

Prevalence of Human Papillomavirus Infection in Unselected SurePath Samples Using the APTIMA HPV mRNA Assay

DEFF Research Database (Denmark)

Rebolj, Matejka; Preisler, Sarah; Ejegod, Ditte M

2013-01-01

The APTIMA Human Papillomavirus (HPV) Assay detects E6/E7 mRNA from 14 human papillomavirus genotypes. Horizon was a population-based split-sample study among well-screened women, with an aim to compare APTIMA, Hybrid Capture 2 (HC2), and liquid-based cytology (LBC) using SurePath samples. APTIMA...

Dual expression of Epstein-Barr virus, latent membrane protein-1 and human papillomavirus-16 E6 transform primary mouse embryonic fibroblasts through NF-κB signaling.

Science.gov (United States)

Shimabuku, Tetsuya; Tamanaha, Ayumi; Kitamura, Bunta; Tanabe, Yasuka; Tawata, Natsumi; Ikehara, Fukino; Arakaki, Kazunari; Kinjo, Takao

2014-01-01

The prevalence of Epstein-Barr virus (EBV) and high-risk human papilloma virus (HPV) infections in patients with oral cancer in Okinawa, southwest islands of Japan, has led to the hypothesis that carcinogenesis is related to EBV and HPV co-infection. To explore the mechanisms of transformation induced by EBV and HPV co-infection, we analyzed the transformation of primary mouse embryonic fibroblasts (MEFs) expressing EBV and HPV-16 genes, alone or in combination. Expression of EBV latent membrane protein-1 (LMP-1) alone or in combination with HPV-16 E6 increased cell proliferation and decreased apoptosis, whereas single expression of EBV nuclear antigen-1 (EBNA-1), or HPV-16 E6 did not. Co-expression of LMP-1 and E6 induced anchorage-independent growth and tumor formation in nude mice, whereas expression of LMP-1 alone did not. Although the singular expression of these viral genes showed increased DNA damage and DNA damage response (DDR), co-expression of LMP-1 and E6 did not induce DDR, which is frequently seen in cancer cells. Furthermore, co-expression of LMP-1 with E6 increased NF-κB signaling, and the knockdown of LMP-1 or E6 in co-expressing cells decreased cell proliferation, anchorage independent growth, and NF-κB activation. These data suggested that expression of individual viral genes is insufficient for inducing transformation and that co-expression of LMP-1 and E6, which is associated with suppression of DDR and increased NF-κB activity, lead to transformation. Our findings demonstrate the synergistic effect by the interaction of oncogenes from different viruses on the transformation of primary MEFs.

HPV16 E6 regulates annexin 1 (ANXA1) protein expression in cervical carcinoma cell lines

International Nuclear Information System (INIS)

Calmon, Marilia Freitas; Sichero, Laura; Boccardo, Enrique; Villa, Luisa Lina; Rahal, Paula

2016-01-01

Annexin 1 (ANXA1) is a substrate for E6AP mediated ubiquitylation. It has been hypothesized that HPV 16 E6 protein redirects E6AP away from ANXA1, increasing its stability and possibly contributing to viral pathogenesis. We analyzed ANXA1 expression in HPV-positive and negative cervical carcinoma-derived cells, in cells expressing HPV-16 oncogenes and in cells transduced with shRNA targeting E6AP. We observed that ANXA1 protein expression increased in HPV-16-positive tumor cells, in keratinocytes expressing HPV-16 E6wt (wild-type) or E6/E7 and C33 cells expressing HPV-16 E6wt. ANXA1 protein expression decreased in cells transfected with E6 Dicer-substrate RNAs (DsiRNA) and C33 cells cotransduced with HPV-16 E6wt and E6AP shRNA. Moreover, colony number and proliferation rate decreased in HPV16-positive cells transduced with ANXA1 shRNA. We observed that in cells infected with HPV16, the E6 binds to E6AP to degrade p53 and upregulate ANXA1. We suggest that ANXA1 may play a role in HPV-mediated carcinogenesis. - Highlights: • ANXA1 upregulation requires the presence of E6 and E6AP and is dependent on E6 integrity. • E6 binds to E6AP to degrade p53 and upregulate ANXA1 in cells infected with HPV16. • ANXA1 plays a role in cell proliferation in HPV-positive cervical cells.

HPV16 E6 regulates annexin 1 (ANXA1) protein expression in cervical carcinoma cell lines

Energy Technology Data Exchange (ETDEWEB)

Calmon, Marilia Freitas [Department of Biology, Institute of Bioscience, Language and Exact Science, São Paulo State University, São Jose do Rio Preto (Brazil); Sichero, Laura [Molecular Biology Laboratory, Centre for Translational Research in Oncology, Instituto do Câncer do Estado de São Paulo (ICESP), São Paulo (Brazil); Boccardo, Enrique [Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo., São Paulo (Brazil); Villa, Luisa Lina [Department of Radiology and Oncology, Faculdade de Medicina, Universidade de São Paulo, São Paulo (Brazil); Rahal, Paula, E-mail: rahalp@yahoo.com.br [Department of Biology, Institute of Bioscience, Language and Exact Science, São Paulo State University, São Jose do Rio Preto (Brazil)

2016-09-15

Annexin 1 (ANXA1) is a substrate for E6AP mediated ubiquitylation. It has been hypothesized that HPV 16 E6 protein redirects E6AP away from ANXA1, increasing its stability and possibly contributing to viral pathogenesis. We analyzed ANXA1 expression in HPV-positive and negative cervical carcinoma-derived cells, in cells expressing HPV-16 oncogenes and in cells transduced with shRNA targeting E6AP. We observed that ANXA1 protein expression increased in HPV-16-positive tumor cells, in keratinocytes expressing HPV-16 E6wt (wild-type) or E6/E7 and C33 cells expressing HPV-16 E6wt. ANXA1 protein expression decreased in cells transfected with E6 Dicer-substrate RNAs (DsiRNA) and C33 cells cotransduced with HPV-16 E6wt and E6AP shRNA. Moreover, colony number and proliferation rate decreased in HPV16-positive cells transduced with ANXA1 shRNA. We observed that in cells infected with HPV16, the E6 binds to E6AP to degrade p53 and upregulate ANXA1. We suggest that ANXA1 may play a role in HPV-mediated carcinogenesis. - Highlights: • ANXA1 upregulation requires the presence of E6 and E6AP and is dependent on E6 integrity. • E6 binds to E6AP to degrade p53 and upregulate ANXA1 in cells infected with HPV16. • ANXA1 plays a role in cell proliferation in HPV-positive cervical cells.

[Experimental study on carcinogenesis by human papillomavirus type 8 E7 gene].

Science.gov (United States)

Nishikawa, T

1994-05-01

Human papillomavirus (HPV) 5 and HPV8 are often detected in skin cancers developed in patients suffering from epidermodysplasia verruciformis, as well as in skin cancers developed in immunosuppressed patients. In the present study, in order to examine the transforming activity of the HPV8E7 gene, the HPV8E7 and HPV8E6/E7 genes were cloned into the expression vector (pcD2-Y), under the SV40 enhancer/promoter to construct pcD2-8E7 and pcD2-8E6/E7, respectively. The E7 and E6/E7 genes of genital high-risk HPV16 were also cloned into pcD2-Y to construct pcD2-16E7 and pcD2-16E6/E7, respectively. They were tested for their ability to collaboratively transform primary rat embryo fibroblasts (REFs) with activated H-ras gene. Transfection experiments of REFs having an activated H-ras gene revealed that pcD2-8E7, as well as pcD2-16E7 and pcD2-16E6/E7, induced transformation of cells in G418-resistant colonies at efficiencies of 11.9%, 43.0% and 53.0%, respectively. Transformed cell lines induced by activated H-ras gene and pcD2-8E7 or pcD2-16E7 were named 8RE and 16RE cell lines, respectively. Tumor induction in syngeneic newborn rats by injected the 8RE cells was higher than that of the 16RE cells. In cytological and histological examination, the 8RE cell lines and their induced tumors were different from the 16RE cell lines and their induced tumors. The 8RE cell lines showed the characteristic transformation with efficient growth ability on plastic and colony formation in 0.3% soft agar. These results support the hypothesis that the HPV8E7 gene plays an important role in the carcinogenesis of skin cancers.

Productive infection of bovine papillomavirus type 2 in the placenta of pregnant cows affected with urinary bladder tumors.

Science.gov (United States)

Roperto, Sante; Borzacchiello, Giuseppe; Esposito, Iolanda; Riccardi, Marita; Urraro, Chiara; Lucà, Roberta; Corteggio, Annunziata; Tatè, Rosarita; Cermola, Michele; Paciello, Orlando; Roperto, Franco

2012-01-01

Papillomaviruses (PVs) are believed to be highly epitheliotropic as they usually establish productive infections within stratified epithelia. In vitro, various PVs appear to complete their entire life-cycle in different trophoblastic cell lines. In this study, infection by and protein expression of bovine papillomavirus type 2 (BPV-2) in the uterine and chorionic epithelium of the placenta has been described in four cows suffering from naturally occurring papillomavirus-associated urothelial bladder tumors. E5 oncoprotein was detected both by Western blot analysis and immunohistochemically. It appears to be complexed and perfectly co-localized with the activated platelet-derived growth factor ß receptor (PDGFßR) by laser scanning confocal microscopy. The activated PDGFßR might be involved in organogenesis and neo-angiogenesis rather than in cell transformation during pregnancy. The major capsid protein, L1, believed to be only expressed in productive papillomavirus infection has been detected by Western blot analysis. Immunohistochemical investigations confirmed the presence of L1 protein both in the cytoplasm and nuclei of cells of the uterine and chorionic epithelium. Trophoblastic cells appear to be the major target for L1 protein expression. Finally, the early protein E2, required for viral DNA replication and known to be expressed during a productive infection, has been detected by Western blot and immunohistochemically. Electron microscopic investigations detected viral particles in nuclei of uterine and chorionic epithelium. This study shows that both active and productive infections by BPV-2 in the placenta of pregnant cows can occur in vivo.

EPIDERMAL GROWTH FACTOR RECEPTOR (EGFR AND HUMAN PAPILLOMAVIRUS (HPV L1 CAPSID PROTEIN IN CERVICAL SQUAMOUS INTRAEPITHELIAL LESIONS

Directory of Open Access Journals (Sweden)

Balan Raluca

2010-09-01

Full Text Available We analyzed the immunohistochemical pattern of epidermal growth factor receptor (EGFR in cervical squamous intraepithelial lesions (SILs in correlation with L1 HPV capsid protein, in order to determine the relationship between EGFR expression and the infection status of human papillomavirus (HPV. The study included 40 cases, 24 LSIL (low grade SIL (CIN1, cervical intraepithelial neoplasia and 16 HSIL (high grade SIL (6 cases of CIN2 and 10 cases of CIN3. The immunoexpression of L1 HPV protein was assessed on conventional cervico-vaginal smears and EGFR was immunohistochemically evaluated on the corresponding cervical biopsies. The HPV L1 capsid protein was expressed in 45.83% of LSIL and 25% of HSIL. EGFR was overexpressed in 62,4% of HSIL (58,4% CIN2 and 41,6% CIN3 and 37,6% LSIL. The immunoexpression of L1 HPV has clinical application in the progression assessment of the cervical precancerous lesions without a correlation to the grade of the cervical SIL. EGFR is expressed by all proliferating squamous epithelial cells, thus corresponding with the grade of SIL. The evaluation of EGFR status, correlated with L1 HPV protein expression, can provide useful data of progression risk of cervical squamous intraepithelial lesions

Production of Human Papilloma Virus Type 16 E6 Oncoprotein as a Recombinant Protein in Eukaryotic Cells

Science.gov (United States)

Mirshahabi, H; Soleimanjahi, H; Pourpak, Z; Meshkat, Z; Hassan, ZM

2012-01-01

Background Cervical cancer is one of the most important and widespread cancer which affects women. There are several causes of cervical cancer; among them HPV types 16 and 18 are the most prominent ones which are recurrent and persistent infections. These genotypes are currently about 70% of cervical cancer causes in developing countries. Due to the importance of these viruses in cervical cancer, we pioneered the production of Human Papilloma Virus type16 E6 oncoprotein as a recombinant protein in order to develop a vaccine. Two HPV oncoproteins, E6 and E7, are consistently expressed in HPV-associated cancer cells and are responsible for malignant transformation. These oncogenic proteins represent ideal target antigens for developing vaccine and immunotherapeutic strategies against HPV-associated neoplasm. Methods In the present study, the cloned E6-oncoprotein of HPV16 in pTZ57R/T-E6 vector was used to produce professional expression vector. The target gene was subcloned in a eukaryotic expression vector. The pcDNA3-E6 vector was propagated in E.coli strain DH5α and transfected into CHO cells 72 hours post-transfection. Results The transfected cells were harvested; mRNA detection and the interest protein production were confirmed by western blot analysis using specific anti E6 monoclonal antibody. Conclusion HPV16-E6 target protein recognized by specific antibody could be an appropriate form of protein, which can be used for further studies. Due to potential effect of this protein, its DNA construction can be used for DNA vaccine in future studies. PMID:25780534

Expression of Human papillomavirus 16 E7ggg oncoprotein on N- and C-terminus of Potato virus X coat protein in bacterial and plant cells

Czech Academy of Sciences Publication Activity Database

Plchová, Helena; Moravec, Tomáš; Hoffmeisterová, Hana; Folwarczna, Jitka; Čeřovská, Noemi

2011-01-01

Roč. 77, č. 2 (2011), s. 146-152 ISSN 1046-5928 R&D Projects: GA ČR GA521/09/1525 Institutional research plan: CEZ:AV0Z50380511 Keywords : Bacterial expression * Human papillomavirus * Oncoprotein E7 Subject RIV: EI - Biotechnology ; Bionics Impact factor: 1.587, year: 2011

Production of recombinant proteins GST L1, E6 and E7 tag HPV 16 ...

African Journals Online (AJOL)

In the present work recombinant proteins were produced for used in LUMINEX in order to undergo serological study of Tunisian female population. HPV types 16 L1, E6 and E7 sequences fused to their 3'-end to a sequence encoding the terminal undecapeptide of the SV40 large T-antigen (tag) were isolated from plasmids ...

Minor Capsid Protein L2 Polytope Induces Broad Protection against Oncogenic and Mucosal Human Papillomaviruses.

Science.gov (United States)

Pouyanfard, Somayeh; Spagnoli, Gloria; Bulli, Lorenzo; Balz, Kathrin; Yang, Fan; Odenwald, Caroline; Seitz, Hanna; Mariz, Filipe C; Bolchi, Angelo; Ottonello, Simone; Müller, Martin

2018-02-15

The amino terminus of the human papillomavirus (HPV) minor capsid protein L2 contains a major cross-neutralization epitope which provides the basis for the development of a broadly protecting HPV vaccine. A wide range of protection against different HPV types would eliminate one of the major drawbacks of the commercial, L1-based prophylactic vaccines. Previously, we have reported that insertion of the L2 epitope into a scaffold composed of bacterial thioredoxin protein generates a potent antigen inducing comprehensive protection against different animal and human papillomaviruses. We also reported, however, that although protection is broad, some oncogenic HPV types escape the neutralizing antibody response, if L2 epitopes from single HPV types are used as immunogen. We were able to compensate for this by applying a mix of thioredoxin proteins carrying L2 epitopes from HPV16, -31, and -51. As the development of a cost-efficient HPV prophylactic vaccines is one of our objectives, this approach is not feasible as it requires the development of multiple good manufacturing production processes in combination with a complex vaccine formulation. Here, we report the development of a thermostable thioredoxin-based single-peptide vaccine carrying an L2 polytope of up to 11 different HPV types. The L2 polytope antigens have excellent abilities in respect to broadness of protection and robustness of induced immune responses. To further increase immunogenicity, we fused the thioredoxin L2 polytope antigen with a heptamerization domain. In the final vaccine design, we achieve protective responses against all 14 oncogenic HPV types that we have analyzed plus the low-risk HPVs 6 and 11 and a number of cutaneous HPVs. IMPORTANCE Infections by a large number of human papillomaviruses lead to malignant and nonmalignant disease. Current commercial vaccines based on virus-like particles (VLPs) effectively protect against some HPV types but fail to do so for most others. Further, only

UV Radiation Activates Toll-Like Receptor 9 Expression in Primary Human Keratinocytes, an Event Inhibited by Human Papillomavirus 38 E6 and E7 Oncoproteins.

Science.gov (United States)

Pacini, Laura; Ceraolo, Maria Grazia; Venuti, Assunta; Melita, Giusi; Hasan, Uzma A; Accardi, Rosita; Tommasino, Massimo

2017-10-01

Several lines of evidence indicate that cutaneous human papillomavirus (HPV) types belonging to the beta genus of the HPV phylogenetic tree synergize with UV radiation in the development of skin cancer. Accordingly, the E6 and E7 oncoproteins from some beta HPV types are able to deregulate pathways related to immune response and cellular transformation. Toll-like receptor 9 (TLR9), in addition to playing a role in innate immunity, has been shown to be involved in the cellular stress response. Using primary human keratinocytes as experimental models, we have shown that UV irradiation (and other cellular stresses) activates TLR9 expression. This event is closely linked to p53 activation. Silencing the expression of p53 or deleting its encoding gene affected the activation of TLR9 expression after UV irradiation. Using various strategies, we have also shown that the transcription factors p53 and c-Jun are recruited onto a specific region of the TLR9 promoter after UV irradiation. Importantly, the E6 and E7 oncoproteins from beta HPV38, by inducing the accumulation of the p53 antagonist ΔNp73α, prevent the UV-mediated recruitment of these transcription factors onto the TLR9 promoter, with subsequent impairment of TLR9 gene expression. This study provides new insight into the mechanism that mediates TLR9 upregulation in response to cellular stresses. In addition, we show that HPV38 E6 and E7 are able to interfere with this mechanism, providing another explanation for the possible cooperation of beta HPV types with UV radiation in skin carcinogenesis. IMPORTANCE Beta HPV types have been suggested to act as cofactors in UV-induced skin carcinogenesis by altering several cellular mechanisms activated by UV radiation. We show that the expression of TLR9, a sensor of damage-associated molecular patterns produced during cellular stress, is activated by UV radiation in primary human keratinocytes (PHKs). Two transcription factors known to be activated by UV radiation, p53

The E1 proteins

International Nuclear Information System (INIS)

Bergvall, Monika; Melendy, Thomas; Archambault, Jacques

2013-01-01

E1, an ATP-dependent DNA helicase, is the only enzyme encoded by papillomaviruses (PVs). It is essential for replication and amplification of the viral episome in the nucleus of infected cells. To do so, E1 assembles into a double-hexamer at the viral origin, unwinds DNA at the origin and ahead of the replication fork and interacts with cellular DNA replication factors. Biochemical and structural studies have revealed the assembly pathway of E1 at the origin and how the enzyme unwinds DNA using a spiral escalator mechanism. E1 is tightly regulated in vivo, in particular by post-translational modifications that restrict its accumulation in the nucleus. Here we review how different functional domains of E1 orchestrate viral DNA replication, with an emphasis on their interactions with substrate DNA, host DNA replication factors and modifying enzymes. These studies have made E1 one of the best characterized helicases and provided unique insights on how PVs usurp different host-cell machineries to replicate and amplify their genome in a tightly controlled manner. - Highlights: • The papillomavirus E1 helicase orchestrates replication of the viral DNA genome. • E1 assembles into a double-hexamer at the viral origin with the help of E2. • E1 interacts with cellular DNA replication factors. • E1 unwinds DNA using a spiral escalator mechanism. • Nuclear accumulation of E1 is regulated by post-translational modifications

Human papillomavirus types detected in skin warts and cancer differ in their transforming properties but commonly counteract UVB induced protective responses in human keratinocytes

Energy Technology Data Exchange (ETDEWEB)

Shterzer, Naama; Heyman, Dariya; Shapiro, Beny; Yaniv, Abraham; Jackman, Anna [Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Tel-Aviv University, Tel-Aviv (Israel); Serour, Francis [Department of Pediatric Surgery, The E. Wolfson Medical Center, Holon (Israel); Chaouat, Malka [Laboratory of Experimental Surgery, Hadassah University Hospital, Ein Karem, Jerusalem (Israel); Gonen, Pinhas [Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Tel-Aviv University, Tel-Aviv (Israel); Tommasino, Massimo [International Agency for Research on Cancer, World Health Organization, Lyon (France); Sherman, Levana [Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Tel-Aviv University, Tel-Aviv (Israel)

2014-11-15

In the present study, E6E7 and E6 proteins of human papillomaviruses (HPVs) associated with skin warts and cancer were compared for their transforming and carcinogenic abilities in primary human keratinocytes (PHKs). We show that E6E7 of cancer associated beta HPV types, notably 49 and 24, were able to extend the life span and enhance the clonogenic efficiency of PHKs when maintained in serum free/low calcium medium. Activities of the beta HPV E6E7 were lower than those of HPV16 E6E7. In contrast, E6 proteins from HPV types detected in skin warts or cancer, notably 10, 49 and 38, attenuated UVB induced protective responses in PHKs including cell death, proliferation arrest and accumulation of the proapoptotic proteins, p53, bax or bak. Together, this investigation revealed functional differences and commonalities between HPVs associated with skin warts and cancer, and allowed the identification of specific properties of beta HPVs supporting their involvement in skin carcinogenesis. - Highlights: • Primary keratinocytes were used to evaluate transforming and carcinogenic abilities of cutaneous HPVs. • E6E7 of cancer associated β HPV types transform primary human keratinocytes. • E6 proteins of cancer and wart associated HPVs inhibit UVB induced cell death. • E6s of cancer and wart associated HPVs attenuate UVB induced proliferation arrest. • E6s of cancer and wart associated HPVs attenuate UVB induced apoptosis signaling.

Human papillomavirus types detected in skin warts and cancer differ in their transforming properties but commonly counteract UVB induced protective responses in human keratinocytes

International Nuclear Information System (INIS)

Shterzer, Naama; Heyman, Dariya; Shapiro, Beny; Yaniv, Abraham; Jackman, Anna; Serour, Francis; Chaouat, Malka; Gonen, Pinhas; Tommasino, Massimo; Sherman, Levana

2014-01-01

In the present study, E6E7 and E6 proteins of human papillomaviruses (HPVs) associated with skin warts and cancer were compared for their transforming and carcinogenic abilities in primary human keratinocytes (PHKs). We show that E6E7 of cancer associated beta HPV types, notably 49 and 24, were able to extend the life span and enhance the clonogenic efficiency of PHKs when maintained in serum free/low calcium medium. Activities of the beta HPV E6E7 were lower than those of HPV16 E6E7. In contrast, E6 proteins from HPV types detected in skin warts or cancer, notably 10, 49 and 38, attenuated UVB induced protective responses in PHKs including cell death, proliferation arrest and accumulation of the proapoptotic proteins, p53, bax or bak. Together, this investigation revealed functional differences and commonalities between HPVs associated with skin warts and cancer, and allowed the identification of specific properties of beta HPVs supporting their involvement in skin carcinogenesis. - Highlights: • Primary keratinocytes were used to evaluate transforming and carcinogenic abilities of cutaneous HPVs. • E6E7 of cancer associated β HPV types transform primary human keratinocytes. • E6 proteins of cancer and wart associated HPVs inhibit UVB induced cell death. • E6s of cancer and wart associated HPVs attenuate UVB induced proliferation arrest. • E6s of cancer and wart associated HPVs attenuate UVB induced apoptosis signaling

Novel snake papillomavirus does not cluster with other non-mammalian papillomaviruses.

Science.gov (United States)

Lange, Christian E; Favrot, Claude; Ackermann, Mathias; Gull, Jessica; Vetsch, Elisabeth; Tobler, Kurt

2011-09-12

Papillomaviruses (PVs) are associated with the development of neoplasias and have been found in several different species, most of them in humans and other mammals. We identified, cloned and sequenced PV DNA from pigmented papilloma-like lesions of a diamond python (Morelia spilota spilota). This represents the first complete PV genome discovered in a Squamata host (MsPV1). It consists of 7048 nt and contains the characteristic open reading (ORF) frames E6, E7, E1, E2, L1 and L2. The L1 ORF sequence showed the highest percentage of sequence identities to human PV5 (57.9%) and Caribbean manatee (Trichechus manatus) PV1 (55.4%), thus, establishing a new clade. According to phylogenetic analysis, the MsPV1 genome clusters with PVs of mammalian rather than sauropsid hosts.

Large-scale analysis of protein expression changes in human keratinocytes immortalized by human papilloma virus type 16 E6 and E7 oncogenes

Directory of Open Access Journals (Sweden)

Arnouk Hilal

2009-08-01

Full Text Available Abstract Background Infection with high-risk type human papilloma viruses (HPVs is associated with cervical carcinomas and with a subset of head and neck squamous cell carcinomas. Viral E6 and E7 oncogenes cooperate to achieve cell immortalization by a mechanism that is not yet fully understood. Here, human keratinocytes were immortalized by long-term expression of HPV type 16 E6 or E7 oncoproteins, or both. Proteomic profiling was used to compare expression levels for 741 discrete protein features. Results Six replicate measurements were performed for each group using two-dimensional difference gel electrophoresis (2D-DIGE. The median within-group coefficient of variation was 19–21%. Significance of between-group differences was tested based on Significance Analysis of Microarray and fold change. Expression of 170 (23% of the protein features changed significantly in immortalized cells compared to primary keratinocytes. Most of these changes were qualitatively similar in cells immortalized by E6, E7, or E6/7 expression, indicating convergence on a common phenotype, but fifteen proteins (~2% were outliers in this regulatory pattern. Ten demonstrated opposite regulation in E6- and E7-expressing cells, including the cell cycle regulator p16INK4a; the carbohydrate binding protein Galectin-7; two differentially migrating forms of the intermediate filament protein Cytokeratin-7; HSPA1A (Hsp70-1; and five unidentified proteins. Five others had a pattern of expression that suggested cooperativity between the co-expressed oncoproteins. Two of these were identified as forms of the small heat shock protein HSPB1 (Hsp27. Conclusion This large-scale analysis provides a framework for understanding the cooperation between E6 and E7 oncoproteins in HPV-driven carcinogenesis.

A novel strategy to improve antigen presentation for active immunotherapy in cancer. Fusion of the human papillomavirus type 16 E7 antigen to a cell penetrating peptide

International Nuclear Information System (INIS)

Granadillo, Milaid; Torrens, Isis; Guerra, Maribel

2012-01-01

Facilitating the delivery of exogenous antigens to antigen-presenting cells, ensuing processing and presentation via the major histocompatibility complex class I and induction of an effective immune response are fundamental for an effective therapeutic cancer vaccine. In this regard, we propose the use of cell-penetrating peptides fused to a tumor antigen. To demonstrate this concept we designed a fusion protein comprising a novel cell-penetrating and immunostimulatory peptide corresponding to residues 32 to 51 of the Limulus anti-lipopolysaccharide factor protein (LALF 32-51 ) linked to human papillomavirus 16 E7 antigen (LALF 32-51 -E7). In this work, we demonstrated that the immunization with LALF 32-51 -E7 using the TC-1 mouse model induces a potent and long-lasting anti-tumor response supported on an effective E7-specific CD8 +T -cell response. The finding that therapeutic immunization with LALF 32-51 or E7 alone, or an admixture of LALF32-51 and E7, does not induce significant tumor reduction indicates that covalent linkage between LALF 32-51 and E7 is required for the anti-tumor effect. These results support the use of this novel cell-penetrating peptide as an efficient means for delivering therapeutic targets into cellular compartments with the induction of a cytotoxic CD8 +T lymphocyte immune response. This approach is promissory for the treatment of tumors associated with the human papillomavirus 16, which is responsible for the 50% of cervical cancer cases worldwide and other malignancies. Furthermore, protein-based vaccines can circumvent the major histocompatibility complex specificity limitation associated with peptide vaccines providing a greater extent in their application

Role of the ubiquitin ligase E6AP/UBE3A in controlling levels of the synaptic protein Arc

Science.gov (United States)

Kühnle, Simone; Mothes, Benedikt; Matentzoglu, Konstantin; Scheffner, Martin

2013-01-01

Inactivation of the ubiquitin ligase E6 associated protein (E6AP) encoded by the UBE3A gene has been associated with development of the Angelman syndrome. Recently, it was reported that in mice, loss of E6AP expression results in increased levels of the synaptic protein Arc and a concomitant impaired synaptic function, providing an explanation for some phenotypic features of Angelman syndrome patients. Accordingly, E6AP has been shown to negatively regulate activity-regulated cytoskeleton-associated protein (Arc) and it has been suggested that E6AP targets Arc for ubiquitination and degradation. In our study, we provide evidence that Arc is not a direct substrate for E6AP and binds only weakly to E6AP, if at all. Furthermore, we show that down-regulation of E6AP expression stimulates estradiol-induced transcription of the Arc gene. Thus, we propose that Arc protein levels are controlled by E6AP at the transcriptional rather than at the posttranslational level. PMID:23671107

Suppression of HPV E6 and E7 expression by BAF53 depletion in cervical cancer cells

International Nuclear Information System (INIS)

Lee, Kiwon; Lee, Ah-Young; Kwon, Yunhee Kim; Kwon, Hyockman

2011-01-01

Highlights: → Integration of HPV into host genome critical for activation of E6 and E7 oncogenes. → BAF53 is essential for higher-order chromatin structure. → BAF53 knockdown suppresses E6 and E7 from HPV integrants, but not from episomal HPVs. → BAF53 knockdown decreases H3K9Ac and H4K12Ac on P105 promoter of integrated HPV 18. → BAF53 knockdown restores the p53-dependent signaling pathway in HeLa and SiHa cells. -- Abstract: Deregulation of the expression of human papillomavirus (HPV) oncogenes E6 and E7 plays a pivotal role in cervical carcinogenesis because the E6 and E7 proteins neutralize p53 and Rb tumor suppressor pathways, respectively. In approximately 90% of all cervical carcinomas, HPVs are found to be integrated into the host genome. Following integration, the core-enhancer element and P105 promoter that control expression of E6 and E7 adopt a chromatin structure that is different from that of episomal HPV, and this has been proposed to contribute to activation of E6 and E7 expression. However, the molecular basis underlying this chromatin structural change remains unknown. Previously, BAF53 has been shown to be essential for the integrity of higher-order chromatin structure and interchromosomal interactions. Here, we examined whether BAF53 is required for activated expression of E6 and E7 genes. We found that BAF53 knockdown led to suppression of expression of E6 and E7 genes from HPV integrants in cervical carcinoma cell lines HeLa and SiHa. Conversely, expression of transiently transfected HPV18-LCR-Luciferase was not suppressed by BAF53 knockdown. The level of the active histone marks H3K9Ac and H4K12Ac on the P105 promoter of integrated HPV 18 was decreased in BAF53 knockdown cells. BAF53 knockdown restored the p53-dependent signaling pathway in HeLa and SiHa cells. These results suggest that activated expression of the E6 and E7 genes of integrated HPV is dependent on BAF53-dependent higher-order chromatin structure or nuclear motor

Development of a PCR Assay to detect Papillomavirus Infection in the Snow Leopard

Directory of Open Access Journals (Sweden)

Eng Curtis

2011-07-01

Full Text Available Abstract Background Papillomaviruses (PVs are a group of small, non-encapsulated, species-specific DNA viruses that have been detected in a variety of mammalian and avian species including humans, canines and felines. PVs cause lesions in the skin and mucous membranes of the host and after persistent infection, a subset of PVs can cause tumors such as cervical malignancies and head and neck squamous cell carcinoma in humans. PVs from several species have been isolated and their genomes have been sequenced, thereby increasing our understanding of the mechanism of viral oncogenesis and allowing for the development of molecular assays for the detection of PV infection. In humans, molecular testing for PV DNA is used to identify patients with persistent infections at risk for developing cervical cancer. In felids, PVs have been isolated and sequenced from oral papillomatous lesions of several wild species including bobcats, Asian lions and snow leopards. Since a number of wild felids are endangered, PV associated disease is a concern and there is a need for molecular tools that can be used to further study papillomavirus in these species. Results We used the sequence of the snow leopard papillomavirus UuPV1 to develop a PCR strategy to amplify viral DNA from samples obtained from captive animals. We designed primer pairs that flank the E6 and E7 viral oncogenes and amplify two DNA fragments encompassing these genes. We detected viral DNA for E6 and E7 in genomic DNA isolated from saliva, but not in paired blood samples from snow leopards. We verified the identity of these PCR products by restriction digest and DNA sequencing. The sequences of the PCR products were 100% identical to the published UuPV1 genome sequence. Conclusions We developed a PCR assay to detect papillomavirus in snow leopards and amplified viral DNA encompassing the E6 and E7 oncogenes specifically in the saliva of animals. This assay could be utilized for the molecular

THE E1 PROTEINS

OpenAIRE

Bergvall, Monika; Melendy, Thomas; Archambault, Jacques

2013-01-01

E1, an ATP-dependent DNA helicase, is the only enzyme encoded by papillomaviruses (PVs). It is essential for replication and amplification of the viral episome in the nucleus of infected cells. To do so, E1 assembles into a double-hexamer at the viral origin, unwinds DNA at the origin and ahead of the replication fork and interacts with cellular DNA replication factors. Biochemical and structural studies have revealed the assembly pathway of E1 at the origin and how the enzyme unwinds DNA usi...

A new cell culture model to genetically dissect the complete human papillomavirus life cycle.

Science.gov (United States)

Bienkowska-Haba, Malgorzata; Luszczek, Wioleta; Myers, Julia E; Keiffer, Timothy R; DiGiuseppe, Stephen; Polk, Paula; Bodily, Jason M; Scott, Rona S; Sapp, Martin

2018-03-01

Herein, we describe a novel infection model that achieves highly efficient infection of primary keratinocytes with human papillomavirus type 16 (HPV16). This cell culture model does not depend on immortalization and is amenable to extensive genetic analyses. In monolayer cell culture, the early but not late promoter was active and yielded a spliced viral transcript pattern similar to HPV16-immortalized keratinocytes. However, relative levels of the E8^E2 transcript increased over time post infection suggesting the expression of this viral repressor is regulated independently of other early proteins and that it may be important for the shift from the establishment to the maintenance phase of the viral life cycle. Both the early and the late promoter were strongly activated when infected cells were subjected to differentiation by growth in methylcellulose. When grown as organotypic raft cultures, HPV16-infected cells expressed late E1^E4 and L1 proteins and replication foci were detected, suggesting that they supported the completion of the viral life cycle. As a proof of principle that the infection system may be used for genetic dissection of viral factors, we analyzed E1, E6 and E7 translation termination linker mutant virus for establishment of infection and genome maintenance. E1 but not E6 and E7 was essential to establish infection. Furthermore, E6 but not E7 was required for episomal genome maintenance. Primary keratinocytes infected with wild type HPV16 immortalized, whereas keratinocytes infected with E6 and E7 knockout virus began to senesce 25 to 35 days post infection. The novel infection model provides a powerful genetic tool to study the role of viral proteins throughout the viral life cycle but especially for immediate early events and enables us to compare low- and high-risk HPV types in the context of infection.

A new cell culture model to genetically dissect the complete human papillomavirus life cycle.

Directory of Open Access Journals (Sweden)

Malgorzata Bienkowska-Haba

2018-03-01

Full Text Available Herein, we describe a novel infection model that achieves highly efficient infection of primary keratinocytes with human papillomavirus type 16 (HPV16. This cell culture model does not depend on immortalization and is amenable to extensive genetic analyses. In monolayer cell culture, the early but not late promoter was active and yielded a spliced viral transcript pattern similar to HPV16-immortalized keratinocytes. However, relative levels of the E8^E2 transcript increased over time post infection suggesting the expression of this viral repressor is regulated independently of other early proteins and that it may be important for the shift from the establishment to the maintenance phase of the viral life cycle. Both the early and the late promoter were strongly activated when infected cells were subjected to differentiation by growth in methylcellulose. When grown as organotypic raft cultures, HPV16-infected cells expressed late E1^E4 and L1 proteins and replication foci were detected, suggesting that they supported the completion of the viral life cycle. As a proof of principle that the infection system may be used for genetic dissection of viral factors, we analyzed E1, E6 and E7 translation termination linker mutant virus for establishment of infection and genome maintenance. E1 but not E6 and E7 was essential to establish infection. Furthermore, E6 but not E7 was required for episomal genome maintenance. Primary keratinocytes infected with wild type HPV16 immortalized, whereas keratinocytes infected with E6 and E7 knockout virus began to senesce 25 to 35 days post infection. The novel infection model provides a powerful genetic tool to study the role of viral proteins throughout the viral life cycle but especially for immediate early events and enables us to compare low- and high-risk HPV types in the context of infection.

Immunization with mutant HPV16 E7 protein inhibits the growth of TC-1 cells in tumor-bearing mice.

Science.gov (United States)

Li, Yan-Li; Ma, Zhong-Liang; Zhao, Yue; Zhang, Jing

2015-04-01

Two human papillomavirus (HPV) 16 oncogenic proteins, E6 and E7, are co-expressed in the majority of HPV16-induced cervical cancer cells. Thus, the E6 and E7 proteins are good targets for developing therapeutic vaccines for cervical cancer. In the present study, immunization with the mutant non-transforming HPV16 E7 (mE7) protein was demonstrated to inhibit the growth of TC-1 cells in the TC-1 mouse model. The HPV16 mE7 gene was amplified by splicing overlap extension polymerase chain reaction using pET-28a(+)-E7 as a template, and the gene was cloned into pET-28a(+) to form pET-28a(+)-mE7. Compared with the E7 protein, mE7 lacks amino acid residues 94-98, and at residue 24, there is a Cys to Gly substitution. pET-28a(+)-mE7 was then introduced into Escherichia coli Rosetta. The expression of mE7 was induced by isopropyl β-D-1-thiogalactopyranoside. The mE7 protein was purified using Ni-NTA agarose and detected by SDS-PAGE and western blot analysis. In the tumor prevention model, no tumor was detected in the mice vaccinated with the mE7 protein. After 40 days, the tumor-free mice and control mice were challenged with 2×10 5 TC-1 cells. All control mice developed tumors six days later, but mE7 immunized mice were tumor free until 90 days. In the tumor therapy model, the TC-1 cells were initially injected subcutaneously, and the mice were subsequently vaccinated. Vaccination against the mE7 protein may significantly inhibit TC-1 cell growth compared to the control. These results demonstrated that immunization with the HPV16 mE7 protein elicited a long-term protective immunity against TC-1 tumor growth and generated a significant inhibition of TC-1 growth in a TC-1 mouse model.

Efficient expression of Human papillomavirus 16 E7 oncoprotein fused to C-terminus of Tobacco mosaic virus (TMV) coat protein using molecular chaperones in Escherichia coli

Czech Academy of Sciences Publication Activity Database

Folwarczna, Jitka; Moravec, Tomáš; Plchová, Helena; Hoffmeisterová, Hana; Čeřovská, Noemi

2012-01-01

Roč. 85, č. 1 (2012), s. 152-157 ISSN 1046-5928 R&D Projects: GA ČR GA521/09/1525; GA ČR GAP501/12/1761 Institutional research plan: CEZ:AV0Z50380511 Keywords : Bacterial expression * Human papillomavirus * E7 oncoprotein Subject RIV: EI - Biotechnology ; Bionics Impact factor: 1.429, year: 2012

Detection of human papillomavirus in oral warts using in situ hybridization

Directory of Open Access Journals (Sweden)

Suzana Orsini Machado de Sousa

2008-01-01

Full Text Available Objective: The human papillomavirus is a group of DNA epitheliotrophic viruses associated with the etiology of benign and malignant oral warts. More than 100 types have been identified and among them, 24 have been found into the oral cavity. The aim of this study was to analyze human papillomavirus prevalence and its subtypes in 50 oral warts, of which 20 were squamous papillomas, 17 condylomaacuminatum and 13 verruca vulgaris. Method: In situ hybridization was used with biotinylated DNA probes for wide-spectrum HPV and with specific probes for human papillomavirus 6/11, human papillomavirus 16/18 and human papillomavirus 31/33. Results: Human papillomavirus was present in ten (20% of the 50 oral wart cases, 03 (3/20 squamous papillomas, 05 (5/17 condyloma acuminatum and 02 (2/13 verruca vulgaris. Of these, 8 (16% were positive to the HPV probe 6/11 being 5 condyloma acuminatum, 1 squamous papilloma and 2 verruca vulgaris. Three cases (6% demonstrated positivity to the human papillomavirus probe 16/18, with 2 being cases of condyloma and the other a case of squamous papilloma. Of the six positive cases to the human papillomavirus probe 31/33, (12% 4 were condyloma acuminatum and 2 squamous papillomas. Conclusion: The human papillomavirus expression (20% found in this study was low, but within the average found in the literature. Nonetheless, in addition to in situ hybridization, other methods may be necessary for confirming the presence of human papillomavirus.

Vaccines against papillomavirus infections and disease

Directory of Open Access Journals (Sweden)

Villa Luisa Lina

2003-01-01

Full Text Available Squamous cell carcinoma of the uterine cervix is the second cause of cancer-related deaths in women, the higher incidence being observed in developing countries. Infection with oncogenic types of human papillomavirus (HPV is considered the major risk factor for the development of malignancies in the uterine cervix. However, HPV is considered to be a necessary but not sufficient cause for cervical cancer and, therefore, other factors contribute to the carcinogenic process, both present in the environment and from the host. Studies performed in animals, and more recently in humans, indicate that vaccination against the capsid proteins of the virus can prevent efficiently from infection. Furthermore, therapeutic vaccines are under investigation aiming the regression of papillomavirus induced tumors. The scientific basis for the development of papillomavirus vaccines and present status of clinical trials will be addressed in this chapter.

Recombinant Kunjin virus replicon vaccines induce protective T-cell immunity against human papillomavirus 16 E7-expressing tumour

International Nuclear Information System (INIS)

Herd, Karen A.; Harvey, Tracey; Khromykh, Alexander A.; Tindle, Robert W.

2004-01-01

The persistence of the E7 oncoprotein in transformed cells in human papillomavirus (HPV)-associated cervical cancer provides a tumour-specific antigen to which immunotherapeutic strategies may be directed. Self-replicating RNA (replicon) vaccine vectors derived from the flavivirus Kunjin (KUN) have recently been reported to induce T-cell immunity. Here, we report that inclusion of a CTL epitope of HPV16 E7 protein into a polyepitope encoded by a KUN vector induced E7-directed T-cell responses and protected mice against challenge with an E7-expressing epithelial tumour. We found replicon RNA packaged into virus-like particles to be more effective than naked replicon RNA or plasmid DNA constructed to allow replicon RNA transcription in vivo. Protective immunity was induced although the E7 CTL epitope was subdominant in the context of other CTL epitopes in the polyepitope. The results demonstrate the efficacy of the KUN replicon vector system for inducing protective immunity directed towards a virally encoded human tumour-specific antigen, and for inducing multi-epitopic CTL responses

Potent anti-tumor effect generated by a novel human papillomavirus (HPV antagonist peptide reactivating the pRb/E2F pathway.

Directory of Open Access Journals (Sweden)

Cai-ping Guo

Full Text Available Human papillomavirus type 16 (HPV16 E7 is a viral oncoprotein believed to play a major role in cervical cancer. In this study, an antagonist peptide against HPV16E7 protein was first identified from screening the c7c phage display peptide library. The binding specificity and affinity of the selected peptide to HPV16E7 were tested by competitive enzyme-linked immunosorbent assay (ELISA. The antagonist peptide showed obvious anti-tumor efficacy both in cell lines and animal tumor models. Significant cell proliferation inhibition with high specificity was noted when HPV16-positive cells were treated with the peptide. This anti-tumor efficacy was resulted from overriding the activities of HPV16E7 and reactivating the pRb/E2F pathway, as shown by a series of experiments. Flow cytometry analysis revealed that the selected peptide induced G1 arrest in a dose-dependent manner. Competitive ELISA, pull down, and Co-IP experiments indicated that the selected peptide disrupted the interaction between HPV16E7 and pRb proteins both in vitro and in vivo. Luciferase reporter assay verified that transcription activities of E2F were suppressed by the peptide through restoration of pRb. RT-PCR and Western blot revealed that it reduced cyclins A, D1, and E1 expression, and led to HPV16E7 protein degradation, but pRb protein stabilization. The current study suggests that this specific peptide may serve as a potential therapeutic agent for HPV16-positive cervical cancer.

Role of p70S6K1-mediated phosphorylation of eIF4B and PDCD4 proteins in the regulation of protein synthesis.

Science.gov (United States)

Dennis, Michael D; Jefferson, Leonard S; Kimball, Scot R

2012-12-14

Modulation of mRNA binding to the 40 S ribosomal subunit during translation initiation controls not only global rates of protein synthesis but also regulates the pattern of protein expression by allowing for selective inclusion, or exclusion, of mRNAs encoding particular proteins from polysomes. The mRNA binding step is modulated by signaling through a protein kinase known as the mechanistic target of rapamycin complex 1 (mTORC1). mTORC1 directly phosphorylates the translational repressors eIF4E binding proteins (4E-BP) 1 and 2, releasing them from the mRNA cap binding protein eIF4E, thereby promoting assembly of the eIF4E·eIF4G complex. mTORC1 also phosphorylates the 70-kDa ribosomal protein S6 kinase 1 (p70S6K1), which subsequently phosphorylates eIF4B, and programmed cell death 4 (PDCD4), which sequesters eIF4A from the eIF4E·eIF4G complex, resulting in repressed translation of mRNAs with highly structured 5'-untranslated regions. In the present study, we compared the role of the 4E-BPs in the regulation of global rates of protein synthesis to that of eIF4B and PDCD4. We found that maintenance of eIF4E interaction with eIF4G was not by itself sufficient to sustain global rates of protein synthesis in the absence of mTORC1 signaling to p70S6K1; phosphorylation of both eIF4B and PDCD4 was additionally required. We also found that the interaction of eIF4E with eIF4G was maintained in the liver of fasted rats as well as in serum-deprived mouse embryo fibroblasts lacking both 4E-BP1 and 4E-BP2, suggesting that the interaction of eIF4G with eIF4E is controlled primarily through the 4E-BPs.

Human papillomavirus type 16 E7 oncoprotein causes a delay in repair of DNA damage

International Nuclear Information System (INIS)

Park, Jung Wook; Nickel, Kwangok P.; Torres, Alexandra D.; Lee, Denis; Lambert, Paul F.; Kimple, Randall J.

2014-01-01

Background and purpose: Patients with human papillomavirus related (HPV+) head and neck cancers (HNCs) demonstrate improved clinical outcomes compared to traditional HPV negative (HPV−) HNC patients. We have recently shown that HPV+ HNC cells are more sensitive to radiation than HPV− HNC cells. However, roles of HPV oncogenes in regulating the response of DNA damage repair remain unknown. Material and methods: Using immortalized normal oral epithelial cell lines, HPV+ HNC derived cell lines, and HPV16 E7-transgenic mice we assessed the repair of DNA damage using γ-H2AX foci, single and split dose clonogenic survival assays, and immunoblot. The ability of E7 to modulate expression of proteins associated with DNA repair pathways was assessed by immunoblot. Results: HPV16 E7 increased retention of γ-H2AX nuclear foci and significantly decreased sublethal DNA damage repair. While phospho-ATM, phospho-ATR, Ku70, and Ku80 expressions were not altered by E7, Rad51 was induced by E7. Correspondingly, HPV+ HNC cell lines showed retention of Rad51 after γ-radiation. Conclusions: Our findings provide further understanding as to how HPV16 E7 manipulates cellular DNA damage responses that may underlie its oncogenic potential and influence the altered sensitivity to radiation seen in HPV+ HNC as compared to HPV− HNC

The mTORC1-4E-BP-eIF4E axis controls de novo Bcl6 protein synthesis in T cells and systemic autoimmunity.

Science.gov (United States)

Yi, Woelsung; Gupta, Sanjay; Ricker, Edd; Manni, Michela; Jessberger, Rolf; Chinenov, Yurii; Molina, Henrik; Pernis, Alessandra B

2017-08-15

Post-transcriptional modifications can control protein abundance, but the extent to which these alterations contribute to the expression of T helper (T H ) lineage-defining factors is unknown. Tight regulation of Bcl6 expression, an essential transcription factor for T follicular helper (T FH ) cells, is critical as aberrant T FH cell expansion is associated with autoimmune diseases, such as systemic lupus erythematosus (SLE). Here we show that lack of the SLE risk variant Def6 results in deregulation of Bcl6 protein synthesis in T cells as a result of enhanced activation of the mTORC1-4E-BP-eIF4E axis, secondary to aberrant assembly of a raptor-p62-TRAF6 complex. Proteomic analysis reveals that this pathway selectively controls the abundance of a subset of proteins. Rapamycin or raptor deletion ameliorates the aberrant T FH cell expansion in mice lacking Def6. Thus deregulation of mTORC1-dependent pathways controlling protein synthesis can result in T-cell dysfunction, indicating a mechanism by which mTORC1 can promote autoimmunity.Excessive expansion of the T follicular helper (T FH ) cell pool is associated with autoimmune disease and Def6 has been identified as an SLE risk variant. Here the authors show that Def6 limits proliferation of T FH cells in mice via alteration of mTORC1 signaling and inhibition of Bcl6 expression.

Identification of a novel bat papillomavirus by metagenomics.

Directory of Open Access Journals (Sweden)

Herman Tse

Full Text Available The discovery of novel viruses in animals expands our knowledge of viral diversity and potentially emerging zoonoses. High-throughput sequencing (HTS technology gives millions or even billions of sequence reads per run, allowing a comprehensive survey of the genetic content within a sample without prior nucleic acid amplification. In this study, we screened 156 rectal swab samples from apparently healthy bats (n = 96, pigs (n = 9, cattles (n = 9, stray dogs (n = 11, stray cats (n = 11 and monkeys (n = 20 using a HTS metagenomics approach. The complete genome of a novel papillomavirus (PV, Miniopterus schreibersii papillomavirus type 1 (MscPV1, with L1 of 60% nucleotide identity to Canine papillomavirus (CPV6, was identified in a specimen from a Common Bent-wing Bat (M. schreibersii. It is about 7.5kb in length, with a G+C content of 45.8% and a genomic organization similar to that of other PVs. Despite the higher nucleotide identity between the genomes of MscPV1 and CPV6, maximum-likelihood phylogenetic analysis of the L1 gene sequence showed that MscPV1 and Erethizon dorsatum papillomavirus (EdPV1 are most closely related. Estimated divergence time of MscPV1 from the EdPV1/MscPV1 common ancestor was approximately 60.2-91.9 millions of years ago, inferred under strict clocks using the L1 and E1 genes. The estimates were limited by the lack of reliable calibration points from co-divergence because of possible host shifts. As the nucleotide sequence of this virus only showed limited similarity with that of related animal PVs, the conventional approach of PCR using consensus primers would be unlikely to have detected the novel virus in the sample. Unlike the first bat papillomavirus RaPV1, MscPV1 was found in an asymptomatic bat with no apparent mucosal or skin lesions whereas RaPV1 was detected in the basosquamous carcinoma of a fruit bat Rousettus aegyptiacus. We propose MscPV1 as the first member of the novel Dyolambda-papillomavirus genus.

HPV-18 E2circumflexE4 chimera: 2 new spliced transcripts and proteins induced by keratinocyte differentiation

Energy Technology Data Exchange (ETDEWEB)

Tan, Chye Ling [Papillomavirus Regulation and Cancer, Institute of Medical Biology, Agency for Science, Technology and Research (A-STAR), Biopolis, 8A Biomedical Grove, Immunos, Singapore 138648 (Singapore); Gunaratne, Jayantha [Mass Spectrometry and Systems Biology Laboratory, Institute of Molecular and Cell Biology, A-STAR, Biopolis, 61 Biopolis Drive, Proteos, Singapore 138673 (Singapore); Lai, Deborah [Papillomavirus Regulation and Cancer, Institute of Medical Biology, Agency for Science, Technology and Research (A-STAR), Biopolis, 8A Biomedical Grove, Immunos, Singapore 138648 (Singapore); Carthagena, Laetitia [UMR-S996, Universite Paris-Sud 11, 32 rue des Carnets, 92140 Clamart (France); Wang, Qian [MRC National Institute for Medical Research, The Ridgeway, Mill Hill, London N10 3UE (United Kingdom); Xue, Yue Zhen; Quek, Ling Shih [Papillomavirus Regulation and Cancer, Institute of Medical Biology, Agency for Science, Technology and Research (A-STAR), Biopolis, 8A Biomedical Grove, Immunos, Singapore 138648 (Singapore); Doorbar, John [MRC National Institute for Medical Research, The Ridgeway, Mill Hill, London N10 3UE (United Kingdom); Bachelerie, Francoise [UMR-S996, Universite Paris-Sud 11, 32 rue des Carnets, 92140 Clamart (France); Thierry, Francoise, E-mail: francoise.thierry@imb.a-star.edu.sg [Papillomavirus Regulation and Cancer, Institute of Medical Biology, Agency for Science, Technology and Research (A-STAR), Biopolis, 8A Biomedical Grove, Immunos, Singapore 138648 (Singapore); Bellanger, Sophie, E-mail: sophie.bellanger@imb.a-star.edu.sg [Papillomavirus Regulation and Cancer, Institute of Medical Biology, Agency for Science, Technology and Research (A-STAR), Biopolis, 8A Biomedical Grove, Immunos, Singapore 138648 (Singapore)

2012-07-20

The Human Papillomavirus (HPV) E4 is known to be synthesized as an E1circumflexE4 fusion resulting from splice donor and acceptor sites conserved across HPV types. Here we demonstrate the existence of 2 HPV-18 E2circumflexE4 transcripts resulting from 2 splice donor sites in the 5 Prime part of E2, while the splice acceptor site is the one used for E1circumflexE4. Both E2circumflexE4 transcripts are up-regulated by keratinocyte differentiation in vitro and can be detected in clinical samples containing low-grade HPV-18-positive cells from Pap smears. They give rise to two fusion proteins in vitro, E2circumflexE4-S and E2circumflexE4-L. Whereas we could not differentiate E2circumflexE4-S from E1circumflexE4 in vivo, E2circumflexE4-L could be formally identified as a 23 kDa protein in raft cultures in which the corresponding transcript was also found, and in a biopsy from a patient with cervical intraepithelial neoplasia stage I-II (CINI-II) associated with HPV-18, demonstrating the physiological relevance of E2circumflexE4 products.

Sentimentos vivenciados por mulheres submetidas a tratamento para Papillomavirus Humano Sentimientos vivenciados por mujeres sometidas a Tratamiento para el Papillomavirus Humano Feelings experienced by women submitted to a treatment for Human Papillomavirus

Directory of Open Access Journals (Sweden)

Ana Luiza Santos de Carvalho

2007-06-01

Full Text Available A carência de informações sobre o papillomavirus humano pode gerar idéias errôneas sobre o tratamento, o que interfere no contexto sócio-familiar da mulher. Com o objetivo de conhecer os sentimentos vivenciados por mulheres submetidas a tratamento de lesões por papillomavirus humano, foi realizada uma pesquisa qualitativa de natureza exploratória com 12 mulheres, baseada na obtenção e análise de depoimentos por meio de entrevista semi-estruturada. As informações foram analisadas de acordo com a literatura e dispostas em duas temáticas: Reações emocionais e Repercussões no relacionamento. Conclui-se que a mulher que está sendo submetida a tratamento de lesões por papillomavirus humano necessita de cuidados, por parte dos enfermeiros, como forma de melhor enfrentar esse período a qual está vivenciando.La carencia de informaciones sobre el papillomavirus humano puede generar ideas erradas sobre el tratamiento, lo que interfiere en el contexto social y familiar de la mujer. Con el objetivo de conocer los sentimientos vividos por mujeres sometidas a tratamiento de lesiones por papillomavirus humanos, fue realizada una investigación cualitativa de naturaleza exploratoria con 12 mujeres, basada en la obtención y análisis de deposiciones por medio de entrevistas medio-estructurada. Las informaciones fueran analizadas conforme con la literatura y dispuestas en dos temáticas: Reacciones emocionales y Repercusiones en el reracionamiento. Concluyese que la mujer que esta siendo sometida al tratamiento de lesiones por papillomavirus humano necesita de cuidados, por parte de los enfermeros, como forma de mejor enfrentar ese periodo el cual esta viviendo.The lack of information on the papillomavirus human can generate misconception on the treatment interfering in the familiar and social context of the woman. With the purpose to know the feelings experienced by women submitted to treatment of lesions by human papillomavirus, was carried

Rapid, large-scale purification and characterization of Ada protein (O sup 6 methylguanine-DNA methyltransferase) of E. coli

Energy Technology Data Exchange (ETDEWEB)

Bhattacharyya, D.; Tano, K.; Bunick, G.J.; Uberbacher, E.C.; Mitra, S. (Oak Ridge National Laboratory, TN (USA)); Behnke, W.D. (Univ. of Cincinnati College of Medicine, OH (USA))

1988-07-25

The E. coli Ada protein (O{sup 6}-methylguanine-DNA methyltransferase) has been purified using a high-level expression vector with a yield of about 3 mg per liter of E. coli culture. The 39-kDa protein has an extinction coefficient (E{sup 280nm}{sub 1%}) of 5.3. Its isoelectric point of 7.1 is lower than that predicted from the amino acid content. The homogeneous Ada protein is fully active as a methyl acceptor from O{sup 6}-methylguanine in DNA. Its reaction with O{sup 6}-methylguanine in a synthetic DNA has a second-order rate constant of 1.1 {times} 10{sup 9} M{sup {minus}1} min{sup {minus}1} at 0{degree}C. Both the native form and the protein methylated at Cys-69 are monomeric. The CD spectrum suggests a low {alpha}-helical content and the radius of gyration of 23 {angstrom} indicates a compact, globular shape. The middle region of the protein is sensitive to a variety of proteases, including an endogenous activity in E. coli, suggesting that the protein is composed of N-terminal and C-terminal domains connected by a hinge region. E. coli B has a higher level of this protease than does K12.

Human papillomavirus type 59 immortalized keratinocytes express late viral proteins and infectious virus after calcium stimulation

International Nuclear Information System (INIS)

Lehr, Elizabeth E.; Qadadri, Brahim; Brown, Calla R.; Brown, Darron R.

2003-01-01

Human papillomavirus type 59 (HPV 59) is an oncogenic type related to HPV 18. HPV 59 was recently propagated in the athymic mouse xenograft system. A continuous keratinocyte cell line infected with HPV 59 was created from a foreskin xenograft grown in an athymic mouse. Cells were cultured beyond passage 50. The cells were highly pleomorphic, containing numerous abnormally shaped nuclei and mitotic figures. HPV 59 sequences were detected in the cells by DNA in situ hybridization in a diffuse nuclear distribution. Southern blots were consistent with an episomal state of HPV 59 DNA at approximately 50 copies per cell. Analysis of the cells using a PCR/reverse blot strip assay, which amplifies a portion of the L1 open reading frame, was strongly positive. Differentiation of cells in monolayers was induced by growth in F medium containing 2 mM calcium chloride for 10 days. Cells were harvested as a single tissue-like sheet, and histologic analysis revealed a four-to-six cell-thick layer. Transcripts encoding involucrin, a cornified envelope protein, and the E1-circumflexE4 and E1-circumflexE4-circumflexL1 viral transcripts were detected after several days of growth in F medium containing 2 mM calcium chloride. The E1-circumflexE4 and L1 proteins were detected by immunohistochemical analysis, and virus particles were seen in electron micrographs in a subset of differentiated cells. An extract of differentiated cells was prepared by vigorous sonication and was used to infect foreskin fragments. These fragments were implanted into athymic mice. HPV 59 was detected in the foreskin xenografts removed 4 months later by DNA in situ hybridization and PCR/reverse blot assay. Thus, the complete viral growth cycle, including production on infectious virus, was demonstrated in the HPV 59 immortalized cells grown in a simple culture system

Enhanced anti-tumor effect of a gene gun-delivered DNA vaccine encoding the human papillomavirus type 16 oncoproteins genetically fused to the herpes simplex virus glycoprotein D

Directory of Open Access Journals (Sweden)

M.O. Diniz

2011-05-01

Full Text Available Anti-cancer DNA vaccines have attracted growing interest as a simple and non-invasive method for both the treatment and prevention of tumors induced by human papillomaviruses. Nonetheless, the low immunogenicity of parenterally administered vaccines, particularly regarding the activation of cytotoxic CD8+ T cell responses, suggests that further improvements in both vaccine composition and administration routes are still required. In the present study, we report the immune responses and anti-tumor effects of a DNA vaccine (pgD-E7E6E5 expressing three proteins (E7, E6, and E5 of the human papillomavirus type 16 genetically fused to the glycoprotein D of the human herpes simplex virus type 1, which was administered to mice by the intradermal (id route using a gene gun. A single id dose of pgD-E7E6E5 (2 µg/dose induced a strong activation of E7-specific interferon-γ (INF-γ-producing CD8+ T cells and full prophylactic anti-tumor effects in the vaccinated mice. Three vaccine doses inhibited tumor growth in 70% of the mice with established tumors. In addition, a single vaccine dose consisting of the co-administration of pgD-E7E6E5 and the vector encoding interleukin-12 or granulocyte-macrophage colony-stimulating factor further enhanced the therapeutic anti-tumor effects and conferred protection to 60 and 50% of the vaccinated mice, respectively. In conclusion, id administration of pgD-E7E6E5 significantly enhanced the immunogenicity and anti-tumor effects of the DNA vaccine, representing a promising administration route for future clinical trials.

Detection of E6/E7 HPV oncogene transcripts as biomarker of cervical intaepithelial displasia

Directory of Open Access Journals (Sweden)

Mauro Carcheri

2009-09-01

Full Text Available It is widely accepted that only persistent infection with high risk types of Human Papillomavirus (HPV HR is a significant risk factor for the development of an invasive squamous cervical cancer. The overexpression of viral oncogenes E6/E7 of HPV is considered a necessary process for incurring in a malignant phenotype.A HPV infection can be identified by detection of HPV DNA in biological samples, but the DNAbased tests cannot delineate between transient or persistent and potentially transforming infection. Instead there is many evidence to suggest that detection of HPV gene expression may constitute a more specific approach to highlight a clinically significant infection. Especially seems that the detection of E6/E7 transcripts can be usefully used for identify the women with a persistent HPV infection that will can induce a future cervical cancer. The aim of our study is to investigate if the detection of oncogenic viral gene activity by detecting transcripts of the E6 and E7 genes can be most usefull of HPV-DNA test in the triage of ASCUS or low grade cervical lesions. Our results confirm that HPV E6/E7 mRNA test can be considered a promising method to stratify HPV positive women for risk of future high-grade cervical lesions or cervical intaepithelial neoplasia.

Impact of human papillomavirus (HPV)-6/11/16/18 vaccine on all HPV-associated genital diseases in young women

DEFF Research Database (Denmark)

Muñoz, Nubia; Kjaer, Susanne K; Sigurdsson, Kristján

2010-01-01

The impact of the prophylactic vaccine against human papillomavirus (HPV) types 6, 11, 16, and 18 (HPV6/11/16/18) on all HPV-associated genital disease was investigated in a population that approximates sexually naive women in that they were "negative to 14 HPV types" and in a mixed population of...

Human papillomavirus type 6 and 11 genetic variants found in 71 oral and anogenital epithelial samples from Australia.

Directory of Open Access Journals (Sweden)

Jennifer A Danielewski

Full Text Available Genetic variation of 49 human papillomavirus (HPV 6 and 22 HPV11 isolates from recurrent respiratory papillomatosis (RRP (n = 17, genital warts (n = 43, anal cancer (n = 6 and cervical neoplasia cells (n = 5, was determined by sequencing the long control region (LCR and the E6 and E7 genes. Comparative analysis of genetic variability was examined to determine whether different disease states resulting from HPV6 or HPV11 infection cluster into distinct variant groups. Sequence variation analysis of HPV6 revealed that isolates cluster into variants within previously described HPV6 lineages, with the majority (65% clustering to HPV6 sublineage B1 across the three genomic regions examined. Overall 72 HPV6 and 25 HPV11 single nucleotide variations, insertions and deletions were observed within samples examined. In addition, missense alterations were observed in the E6/E7 genes for 6 HPV6 and 5 HPV11 variants. No nucleotide variations were identified in any isolates at the four E2 binding sites for HPV6 or HPV11, nor were any isolates found to be identical to the HPV6 lineage A or HPV11 sublineage A1 reference genomes. Overall, a high degree of sequence conservation was observed between isolates across each of the regions investigated for both HPV6 and HPV11. Genetic variants identified a slight association with HPV6 and anogenital lesions (p = 0.04. This study provides important information on the genetic diversity of circulating HPV 6 and HPV11 variants within the Australian population and supports the observation that the majority of HPV6 isolates cluster to the HPV6 sublineage B1 with anogenital lesions demonstrating an association with this sublineage (p = 0.02. Comparative analysis of Australian isolates for both HPV6 and HPV11 to those from other geographical regions based on the LCR revealed a high degree of sequence similarity throughout the world, confirming previous observations that there are no geographically specific variants for these

Highly potent and specific siRNAs against E6 or E7 genes of HPV16- or HPV18-infected cervical cancers

OpenAIRE

Chang, J T-C; Kuo, T-F; Chen, Y-J; Chiu, C-C; Lu, Y-C; Li, H-F; Shen, C-R; Cheng, A-J

2010-01-01

Infection with high-risk types (type 16 or type 18) of human papillomaviruses (HPVs) increases a patient's risk of cervical cancer. Given the importance of the cervix and the severe side effects resulting from traditional cancer therapies, this study aimed to achieve targeted inhibition of viral oncogenes in tumor cells using small interfering RNAs (siRNA). To accomplish this, we developed nine siRNAs against either the E6 or E7 genes of HPV-16 or HPV-18 in several combinations, yielding siRN...

Longitudinal Psychosocial Adjustment of Women to Human Papillomavirus Infection.

Science.gov (United States)

Hsu, Yu-Yun; Wang, Wei-Ming; Fetzer, Susan Jane; Cheng, Ya-Min; Hsu, Keng-Fu

2018-05-29

The aim of this study was to examine the psychosocial adjustment trajectory, focusing on psychological distress, sexual relationships and health care information, as well as factors which have an impact on adjustment on receiving a positive diagnosis of human papillomavirus infection. Human papillomavirus is a common sexually transmitted infection in females. To date, knowledge of the longitudinal psychosocial response to the diagnosis of human papillomavirus is limited. A prospective longitudinal design was conducted with a convenience sample. Women aged 20-65 years old were followed at one, 6 and 12 months after a diagnosis of HPV. Participants completed measures of initial emotional distress and followed-up psychosocial adjustment. A mixed-effects model was applied to analyze the longitudinal changes in psychosocial adjustment. Seventy human papillomavirus positive women participated in the study with nearly 20% of the women reporting emotional distress during their first visit. Mixed-effects model analyses showed that a trajectory of psychosocial adjustment in health care orientation, sexual relationship and psychosocial distress occur from one to 6 months after HPV diagnosis. However, a declining trend from 6-12 months was significant in health care orientation. Initial emotional distress was associated with changes in psychological adjustment. Psychosocial adjustment to human papillomavirus was worse at one month compared with 6 and 12 months after diagnosis. Healthcare providers should offer health information and psychosocial support to women according to their disease progression. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Sensitivity, Specificity, and Clinical Value of Human Papillomavirus (HPV) E6/E7 mRNA Assay as a Triage Test for Cervical Cytology and HPV DNA Test ▿

Science.gov (United States)

Benevolo, Maria; Vocaturo, Amina; Caraceni, Donatella; French, Deborah; Rosini, Sandra; Zappacosta, Roberta; Terrenato, Irene; Ciccocioppo, Lucia; Frega, Antonio; Rossi, Paolo Giorgi

2011-01-01

There is evidence that testing for human papillomavirus (HPV) E6/E7 mRNA is more specific than testing for HPV DNA. A retrospective study was carried out to evaluate the performance of the PreTect HPV-Proofer E6/E7 mRNA assay (Norchip) as a triage test for cytology and HPV DNA testing. This study analyzed 1,201 women, 688 of whom had a colposcopy follow-up and 195 of whom had histology-confirmed high-grade intraepithelial neoplasia or worse (CIN2+). The proportion of positive results and the sensitivity and specificity for CIN2+ were determined for HPV mRNA in comparison to HPV DNA and cytology. All data were adjusted for follow-up completeness. Stratified by cytological grades, the HPV mRNA sensitivity was 83% (95% confidence interval [CI] = 63 to 94%) in ASC-US (atypical squamous cells of undetermined significance), 62% (95% CI = 47 to 75%) in L-SIL (low-grade squamous intraepithelial lesion), and 67% (95% CI = 57 to 76%) in H-SIL (high-grade squamous intraepithelial lesion). The corresponding figures were 99, 91, and 96%, respectively, for HPV DNA. The specificities were 82, 76, and 45%, respectively, for HPV mRNA and 29, 13, and 4%, respectively, for HPV DNA. Used as a triage test for ASC-US and L-SIL, mRNA reduced colposcopies by 79% (95% CI = 74 to 83%) and 69% (95% CI = 65 to 74%), respectively, while HPV DNA reduced colposcopies by 38% (95% CI = 32 to 44%) and by 15% (95% CI = 12 to 19%), respectively. As a HPV DNA positivity triage test, mRNA reduced colposcopies by 63% (95% CI = 60 to 66%), having 68% sensitivity (95% CI = 61 to 75%), whereas cytology at the ASC-US+ threshold reduced colposcopies by 23% (95% CI = 20 to 26%), showing 92% sensitivity (95% CI = 87 to 95%). In conclusion, PreTect HPV-Proofer mRNA can serve as a better triage test than HPV DNA to reduce colposcopy referral in both ASC-US and L-SIL. It is also more efficient than cytology for the triage of HPV DNA-positive women. Nevertheless, its low sensitivity demands a strict follow-up of

Use of human papillomavirus DNA, E6/E7 mRNA, and p16 immunocytochemistry to detect and predict anal high-grade squamous intraepithelial lesions in HIV-positive and HIV-negative men who have sex with men.

Directory of Open Access Journals (Sweden)

Nittaya Phanuphak

Full Text Available Men who have sex with men (MSM are at high risk of having anal cancer. Anal high-grade squamous intraepithelial lesion (HSIL is the precursor of anal cancer. We explored the use of different biomarkers associated with human papillomavirus (HPV infection and HPV-mediated cell transformation to detect and predict HSIL among HIV-positive and HIV-negative MSM.A total of 123 HIV-positive and 123 HIV-negative MSM were enrolled and followed for 12 months. High-resolution anoscopy (HRA with biopsies were performed at every visit along with anal sample collection for cytology, high-risk HPV DNA genotyping, HPV E6/E7 mRNA, and p16 immunocytochemistry. Performance characteristics and area under the receiver operator characteristics curve were calculated for these biomarkers at baseline, and Cox regression compared the usefulness of these biomarkers in predicting incident HSIL. High-risk HPV DNA, E6/E7 mRNA, and p16 immunocytochemistry each identified 43-46% of MSM whose baseline test positivity would trigger HRA referral. E6/E7 mRNA had the highest sensitivity (64.7% and correctly classified the highest number of prevalent HSIL cases. With the exception of p16 immunochemistry, most tests showed significant increases in sensitivity but decreases specificity versus anal cytology, while the overall number of correctly classified cases was not significantly different. Baseline or persistent type 16 and/or 18 HPV DNA was the only test significantly predicting incident histologic HSIL within 12 months in models adjusted for HIV status and low-grade squamous intraepithelial lesions at baseline.Countries with a high HIV prevalence among MSM and limited HRA resources may consider using biomarkers to identify individuals at high risk of HSIL. E6/E7 mRNA had the highest sensitivity for prevalent HSIL detection regardless of HIV status, whereas type 16 and/or 18 HPV DNA performed best in predicting development of incident HSIL within 12 months.

Characterization of two novel cutaneous human papillomaviruses, HPV93 and HPV96

DEFF Research Database (Denmark)

Vasiljevic, Natasa; Hazard, Kristina; Eliasson, Linda

2007-01-01

Two novel human papillomaviruses (HPVs), HPV93 and HPV96, with genomes of 7450 and 7438 bp, respectively, are described. The L1 open reading frame of HPV93 showed highest identity to HPV24 (79%) and that of HPV96 had highest identity to HPV92 (71%). Real-time PCR for HPV92, 93 and 96 on stripped ...... per 45 cells to one copy per 10,000 cells. The E7 proteins of HPV92, 93 and 96 were found to bind the retinoblastoma protein (pRb). These results suggest a possible role for these HPV types in skin carcinogenesis that deserves further study....

The high-risk HPV E6 target scribble (hScrib is required for HPV E6 expression in cervical tumour-derived cell lines

Directory of Open Access Journals (Sweden)

Christian Kranjec

2016-12-01

Full Text Available The ability of high-risk HPV E6 oncoproteins to target cellular proteins which harbor PDZ domains is believed to play an important role in the virus life cycle and to influence the ability of these viruses to bring about malignant transformation. Whilst many of these PDZ proteins are potential tumour suppressors, involved in the control of cell polarity and cell-contact, recent studies suggest that mislocalisation or overexpression might result in the emergence of oncogenic functions. This has been shown most clearly for two E6 targets, hDlg and hScrib. In this study we show that hScrib plays such a role in HeLa cells, where its expression is required for maintaining high levels of HPV-18 E6 protein. Loss of hScrib has no effect on E6 stability but results in lower levels of E6 transcription and a reduced rate of E6 translation. We further show that, in the context of cervical tumour-derived cell lines, both hScrib and E6 cooperate in the activation of the S6 kinase signaling pathway, and thereby contribute towards maintaining high rates of protein translation. These results indicate that the residual hScrib that is present within HPV transformed cells is pro-oncogenic, and highlights the dual functions of E6 cell polarity targets. Keywords: HPV E6, hScrib, S6 kinase, Protein translation

Genetic variability in E6 and E7 oncogenes of human papillomavirus Type 16 from Congolese cervical cancer isolates

OpenAIRE

Boumba, Luc Magloire Anicet; Assoumou, Samira Zoa; Hilali, Lahoucine; Mambou, Jean Victor; Moukassa, Donatien; Ennaji, Mustapha Moulay

2015-01-01

Background The molecular epidemiological studies showed that some variants of HPV-16, distributed geographically, would present a higher risk of causing cervical cancer. This study aimed to analyze nucleotide changes of HPV-16 E6 and E7 genomic regions from infected Southwestern Congolese women. Methods DNA of twenty HPV-16 isolates was analyzed by amplifying the E6 and E7 genes using type-specific primers PCR and direct sequencing. The sequences obtained were aligned with the HPV-16 GenBank ...

A vaccine of L2 epitope repeats fused with a modified IgG1 Fc induced cross-neutralizing antibodies and protective immunity against divergent human papillomavirus types.

Science.gov (United States)

Chen, Xue; Liu, Hongyang; Zhang, Ting; Liu, Yanchun; Xie, Xixiu; Wang, Zhirong; Xu, Xuemei

2014-01-01

Current human papillomavirus (HPV) major capsid protein L1 virus-like particles (VLPs)-based vaccines in clinic induce strong HPV type-specific neutralizing antibody responses. To develop pan-HPV vaccines, here, we show that the fusion protein E3R4 consisting of three repeats of HPV16 L2 aa 17-36 epitope (E3) and a modified human IgG1 Fc scaffold (R4) induces cross-neutralizing antibodies and protective immunity against divergent HPV types. E3R4 was expressed as a secreted protein in baculovirus expression system and could be simply purified by one step Protein A affinity chromatography with the purity above 90%. Vaccination of E3R4 formulated with Freunds adjuvant not only induced cross-neutralizing antibodies against HPV pseudovirus types 16, 18, 45, 52, 58, 6, 11 and 5 in mice, but also protected mice against vaginal challenges with HPV pseudovirus types 16, 45, 52, 58, 11 and 5 for at least eleven months after the first immunization. Moreover, vaccination of E3R4 formulated with FDA approved adjuvant alum plus monophosphoryl lipid A also induced cross-neutralizing antibodies against HPV types 16, 18 and 6 in rabbits. Thus, our results demonstrate that delivery of L2 antigen as a modified Fc-fusion protein may facilitate pan-HPV vaccine development.

HPV (Human Papillomavirus)

Science.gov (United States)

... Consumers Consumer Information by Audience For Women HPV (human papillomavirus) Share Tweet Linkedin Pin it More sharing ... Español In Chamorro In Urdu In Vietnamese HPV (human papillomavirus) is a sexually transmitted virus. It is ...

GRIM-19 disrupts E6/E6AP complex to rescue p53 and induce apoptosis in cervical cancers.

Directory of Open Access Journals (Sweden)

Ying Zhou

Full Text Available BACKGROUND: Our previous studies showed a down-regulation of GRIM-19 in primary human cervical cancers, and restoration of GRIM-19 induced tumor regression. The induction of tumor suppressor protein p53 ubiquitination and degradation by E6 oncoportein of high risk-HPV through forming a stable complex with E6AP is considered as a critical mechanism for cervical tumor development. The aims of this study were to determine the potential role of GRIM-19 in rescuing p53 protein and inducing cervical cancer cell apoptosis. METHODOLOGY/PRINCIPAL FINDINGS: The protein levels of GRIM-19 and p53 were detected in normal cervical tissues from 45 patients who underwent hysterectomy for reasons other than neoplasias of either the cervix or endometrium, and cervical cancer tissues from 60 patients with non-metastatic squamous epithelial carcinomas. Coimmunoprecipitation and GST pull-down assay were performed to examine the interaction of GRIM-19 with 18E6 and E6AP in vivo and in vitro respectively. The competition of 18E6 with E6AP in binding GRIM-19 by performing competition pull-down assays was designed to examine the disruption of E6/E6AP complex by GRIM-19. The augment of E6AP ubiquitination by GRIM-19 was detected in vivo and in vitro ubiquitination assay. The effects of GRIM-19-dependent p53 accumulation on cell proliferation, cell cycle, apoptosis were explored by MTT, flow cytometry and transmission electron microscopy respectively. The tumor suppression was detected by xenograft mouse model. CONCLUSION/SIGNIFICANCE: The levels of GRIM-19 and p53 were concurrently down regulated in cervical cancers. The restoration of GRIM-19 can induce ubiquitination and degradation of E6AP, and disrupt the E6/E6AP complex through the interaction of N-terminus of GRIM-19 with both E6 and E6AP, which protected p53 from degradation and promoted cell apoptosis. Tumor xenograft studies also revealed the suppression of p53 degradation in presence of GRIM-19. These data

Metastatic MHC class I-negative mouse cells derived by transformation with human papillomavirus type 16

Czech Academy of Sciences Publication Activity Database

Šmahel, M.; Sobotková, E.; Bubeník, Jan; Šímová, Jana; Žák, R.; Ludvíková, V.; Mikyšková, Romana; Kovařík, J.; Jelínek, F.; Povýšil, C.; Marinov, J.; Vonka, V.

2001-01-01

Roč. 84, č. 3 (2001), s. 374-380 ISSN 0007-0920 R&D Projects: GA MZd NC5900; GA MZd NC5526; GA ČR GA312/99/0542; GA ČR GA312/98/0826 Institutional research plan: CEZ:AV0Z5052915 Keywords : human papillomavirus * E6/E7 oncogenes * cell transformation Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.942, year: 2001

A promoter within the E6 ORF of human papillomavirus type 16 contributes to the expression of the E7 oncoprotein from a monocistronic mRNA

DEFF Research Database (Denmark)

Glahder, Jacob-Andreas Harald; Hansen, Christina N; Vinther, Jeppe

2003-01-01

RNA that encodes E7 as the first open reading frame (ORF) has been identified. We recently identified a transcription initiation site within the E6 ORF of HPV-16 at nt 542. In the present study we have characterized the P542 promoter, which putatively controls monocistronic expression of E7. The monocistronic m...... from nt 226 to 409. Furthermore, the translation initiation of E7 is most abundant from the monocistronic mRNA. We have also shown that the P542 promoter is downregulated by the transcription factor activator protein 4 (AP-4) and the differentiation-dependent factor hSkn-1a, both binding downstream...... of the transcription initiation site. In conclusion, we have found that P542 is a relatively weak promoter compared with P97 and may be downregulated in differentiated epithelial cells....

[Human papillomavirus infection and adolescence].

Science.gov (United States)

Sam Soto, Selene; de la Peña y Carranza, Alejandro Ortiz; Plascencia, Josefina Lira

2011-04-01

Infection with human papillomavirus has increased dramatically in recent years. The highest prevalence rates are among adolescents and young women, reflecting changes in sexual behavior associated with biological factors in adolescent development. Adolescents who begin sexual activity early are at greater risk of precursor lesions and cervical cancer. There are adolescents with special circumstances, where no early decision should be delayed cervical cytology and in whom it is important to initiate consultations and periodic reviews with a preventive approach. Cervical cancer can be avoided when the diagnosis and treatment of precursor lesions is early. Despite efforts at sex education based on "safe sex" with the correct use of condoms has not been able to reduce the incidence of infections with human papillomavirus in adolescents. While better than nothing, condom use is not 100% reliable. Studies show that consistent and correct use provides protection against the human papillomavirus only 70%. In Mexico, reported an overall ratio of actual use of condoms from 24.6%. It is clear that the physician who provides care for adolescents plays a fundamental role in sex education. The key to future prevention of cervical cancer and its precursor lesions could be the vaccination.

One Family's Struggles with HPV (Human Papillomavirus)

Medline Plus

Full Text Available ... sq how to do kids infect kids links & resources M.O.V.E. parents for prevention ... go to GETVAXED.ORG cme Immunizations HPV (Human Papillomavirus) One family's struggles with HPV We provide ...

Human papillomavirus molecular biology.

Science.gov (United States)

Harden, Mallory E; Munger, Karl

Human papillomaviruses are small DNA viruses with a tropism for squamous epithelia. A unique aspect of human papillomavirus molecular biology involves dependence on the differentiation status of the host epithelial cell to complete the viral lifecycle. A small group of these viruses are the etiologic agents of several types of human cancers, including oral and anogenital tract carcinomas. This review focuses on the basic molecular biology of human papillomaviruses. Copyright © 2016 Elsevier B.V. All rights reserved.

Subclinical human papillomavirus infection of the cervix

International Nuclear Information System (INIS)

Al-Waiz, M.; Al-Saadi, Rabab N.; Al-Saadi, Zahida A.; Al-Rawi, Faiza A.

2001-01-01

A prospective study to investigate a group of Iraqi woman with proved genital vulval warts, to seek evidence of human papillomavirus infection in apparently normal looking cervixes and to investigate the natural history of infection. From December 1997 to August 1998, 20 women with vulval warts were enrolled along with 20 aged-matched control cases without warts. Their ages ranged between 19-48 years with a mean of 30.4 years, (+/- standard deviation = 2.3) for patients and 18-48 years with a mean of 29.7 (+/- standard deviation = 2.7) for the control group. General and gynecological examinations were carried out. Cervical swabs for associated genital infection, papilloma smears, speculoscopy and directed punch biopsies were carried out to detect subclinical human papillomavirus infections of the cervix and associated intraepithelial neoplasm. Cytology results showed that 11 (55%) of patients had evidence of cervical infection by human papillomavirus, 6 (30%) showed mild dysplastic changes, 3 (15%) showed moderate dysplastic changes, whilst 2 (10%) showed no dysplastic changes. Speculoscopy and acetowhitening was positive in 11 (55%) and collated histological results showed evidence of human papillomavirus infection in 9 patients (45%). As for the control group one case (5%) had evidence of human papillomavirus infection. Subclinical human papillomavirus infection is more common than was previously thought among Iraqi women. It may appear alone or in association with vulval or exophytic cervical warts, or both, and may be more common than the clinically obvious disease. Speculoscopy as an adjunctive method to colposcopy was found to be a simple and an easy to perform technique. Its combination with cytology gave relatively good results when it was used as a triage instrument, and may have a more promising performance in the future. (author)

In vitro and in vivo growth suppression of human papillomavirus 16-positive cervical cancer cells by CRISPR/Cas9

International Nuclear Information System (INIS)

Zhen, Shuai; Hua, Ling; Takahashi, Y.; Narita, S.; Liu, Yun-Hui; Li, Yan

2014-01-01

Highlights: • Established CRISPR/Cas9 targeting promoter of HPV 16 and targeting E6, E7 transcript. • CRISPR/Cas9 resulted in accumulation of p53 and p21, reduced the proliferation of cervical cancer cells. • Finding inhibited tumorigenesis and growth of mice incubated by cells with CRISPR/Cas9. • CRISPR/Cas9 will be a new treatment strategy, in cervical and other HPV-associated cancer therapy. - Abstract: Deregulated expression of high-risk human papillomavirus oncogenes (E6 and E7) is a pivotal event for pathogenesis and progression in cervical cancer. Both viral oncogenes are therefore regarded as ideal therapeutic targets. In the hope of developing a gene-specific therapy for HPV-related cancer, we established CRISPR/Cas9 targeting promoter of HPV 16 E6/E7 and targeting E6, E7 transcript, transduced the CRISPR/Cas9 into cervical HPV-16-positive cell line SiHa. The results showed that CRISPR/Cas9 targeting promoter, as well as targeting E6 and E7 resulted in accumulation of p53 and p21 protein, and consequently remarkably reduced the abilities of proliferation of cervical cancer cells in vitro. Then we inoculated subcutaneously cells into nude mice to establish the transplanted tumor animal models, and found dramatically inhibited tumorigenesis and growth of mice incubated by cells with CRISPR/Cas9 targeting (promoter+E6+E7)-transcript. Our results may provide evidence for application of CRISPR/Cas9 targeting HR-HPV key oncogenes, as a new treatment strategy, in cervical and other HPV-associated cancer therapy

In vitro and in vivo growth suppression of human papillomavirus 16-positive cervical cancer cells by CRISPR/Cas9

Energy Technology Data Exchange (ETDEWEB)

Zhen, Shuai [Baoji Maternal and Child Health Hospital, 2 Xinjian Road East, WeiBin District, Baoji City, 721000, Shanxi Province (China); Xijing Hospital, Fourth Military Medical University, Xi’an (China); Department of Pharmacology and Toxicology, Beijing Institute of Radiation Medicine, Beijing 100850 (China); Kyoto University, Kyoto 606-8507 (Japan); Hua, Ling [Department of Pharmacology and Toxicology, Beijing Institute of Radiation Medicine, Beijing 100850 (China); Takahashi, Y.; Narita, S. [Kyoto University, Kyoto 606-8507 (Japan); Liu, Yun-Hui [Department of Pharmacology and Toxicology, Beijing Institute of Radiation Medicine, Beijing 100850 (China); Li, Yan [Baoji Hospital of Traditional Chinese Medicine, No 43, BaoFu Road, Baoji City, Shanxi Province (China)

2014-08-08

Highlights: • Established CRISPR/Cas9 targeting promoter of HPV 16 and targeting E6, E7 transcript. • CRISPR/Cas9 resulted in accumulation of p53 and p21, reduced the proliferation of cervical cancer cells. • Finding inhibited tumorigenesis and growth of mice incubated by cells with CRISPR/Cas9. • CRISPR/Cas9 will be a new treatment strategy, in cervical and other HPV-associated cancer therapy. - Abstract: Deregulated expression of high-risk human papillomavirus oncogenes (E6 and E7) is a pivotal event for pathogenesis and progression in cervical cancer. Both viral oncogenes are therefore regarded as ideal therapeutic targets. In the hope of developing a gene-specific therapy for HPV-related cancer, we established CRISPR/Cas9 targeting promoter of HPV 16 E6/E7 and targeting E6, E7 transcript, transduced the CRISPR/Cas9 into cervical HPV-16-positive cell line SiHa. The results showed that CRISPR/Cas9 targeting promoter, as well as targeting E6 and E7 resulted in accumulation of p53 and p21 protein, and consequently remarkably reduced the abilities of proliferation of cervical cancer cells in vitro. Then we inoculated subcutaneously cells into nude mice to establish the transplanted tumor animal models, and found dramatically inhibited tumorigenesis and growth of mice incubated by cells with CRISPR/Cas9 targeting (promoter+E6+E7)-transcript. Our results may provide evidence for application of CRISPR/Cas9 targeting HR-HPV key oncogenes, as a new treatment strategy, in cervical and other HPV-associated cancer therapy.

HPV E6 and E7 in hypoxia mediated tumorigenesis in cervical epithelial cells

International Nuclear Information System (INIS)

Kim, Charlotte Y.; Tsai, Mitchell; Graeber, Thomas G.; Peehl, Donna M.; Giaccia, Amato J.

1996-01-01

Objective: In our previous work, we found that hypoxia induces apoptosis in oncogenically transformed rodent cells and loss of the p53 tumor suppressor gene significantly reduces hypoxia induced cell death. In this report, we show that transformation of wild-type p53 expressing primary cervical epithelial cells with the E6 and E7 genes from high risk human papillomavirus (HPV) type 16 dramatically enhances their susceptibility to hypoxia induced apoptosis. Materials and Methods: Sub confluent primary normal human cervical epithelial cells and normal human fibroblasts were infected with retroviral vectors containing HPV16 E6 and E7 and the neomycin selectable marker using previously described techniques. Clones were selected and isolated in neomycin containing media. Exponentially growing cells were treated with hypoxia (0.02% O 2 ) using specially designed chambers, irradiated (800 cGy) using a cesium source, or grown under aerobic conditions (20% O 2 ) as a control. After treatment, cells were stained with Hoescht and propidium iodide and viewed with a fluorescent microscope for analysis of apoptotic cells. To determine increase in expression of p53, immuno blots were performed using whole cell extracts. Results: After a 48 hour exposure to hypoxic conditions, 40% of E6 and E7 transformed cervical cells exhibit morphologic features indicative of apoptosis, compared to 5% of untransformed cervical cells. Exposure of HPV E6 and E7 transformed cells to ionizing radiation, however, did not initiate apoptosis. Immunoblot assays show induction of p53 under hypoxic conditions but not by ionizing radiation, indicating that hypoxia is able to induce p53 in the presence of E6 and that hypoxia activates p53 by a pathway which is distinct from that of ionizing radiation. Furthermore, hypoxia did not induce apoptosis in normal human fibroblasts transformed with E6 and E7, suggesting that the cellular response to hypoxia is influenced by the cell type. Conclusion: These results

Identification and validation of human papillomavirus encoded microRNAs.

Directory of Open Access Journals (Sweden)

Kui Qian

Full Text Available We report here identification and validation of the first papillomavirus encoded microRNAs expressed in human cervical lesions and cell lines. We established small RNA libraries from ten human papillomavirus associated cervical lesions including cancer and two human papillomavirus harboring cell lines. These libraries were sequenced using SOLiD 4 technology. We used the sequencing data to predict putative viral microRNAs and discovered nine putative papillomavirus encoded microRNAs. Validation was performed for five candidates, four of which were successfully validated by qPCR from cervical tissue samples and cell lines: two were encoded by HPV 16, one by HPV 38 and one by HPV 68. The expression of HPV 16 microRNAs was further confirmed by in situ hybridization, and colocalization with p16INK4A was established. Prediction of cellular target genes of HPV 16 encoded microRNAs suggests that they may play a role in cell cycle, immune functions, cell adhesion and migration, development, and cancer. Two putative viral target sites for the two validated HPV 16 miRNAs were mapped to the E5 gene, one in the E1 gene, two in the L1 gene and one in the LCR region. This is the first report to show that papillomaviruses encode their own microRNA species. Importantly, microRNAs were found in libraries established from human cervical disease and carcinoma cell lines, and their expression was confirmed in additional tissue samples. To our knowledge, this is also the first paper to use in situ hybridization to show the expression of a viral microRNA in human tissue.

Efficacy of human papillomavirus l1 protein vaccines (cervarix and gardasil in reducing the risk of cervical intraepithelial neoplasia: A meta-analysis

Directory of Open Access Journals (Sweden)

Mohammad Reza Haghshenas

2017-01-01

Full Text Available Human papillomavirus (HPV can induce cervical intraepithelial neoplasia (CIN. Vaccination against HPV can play an important role in CIN prevention. This study aims to estimate the efficacy of L1 protein vaccines (Cervarix and Gardasil in CIN 1, 2, 3 risk reduction using meta-analysis. Relevant articles were identified by two independent researchers searching international databanks. After application of inclusion/exclusion criteria and quality assessment, eligible articles were entered into the final meta-analysis. Inverse variance method and fixed effect model were used to combine the results of the primary studies. The heterogeneity between the results was assessed using Cochrane and I2 indices. Of 11,530 evidence identified during the primary search, three papers were found eligible for meta-analysis, including 7213 participants in the intervention groups and 7170 healthy controls. The efficacy (95% confidence interval of HPV 6, 11, 16, 18 monovalent and quadrivalent vaccines against CIN 1, CIN 2, and CIN 3 were estimated as of 95% (88–98, 97% (85–99, and 95% (78–99, respectively. This study showed that L1 protein vaccines Cervarix and Gardasil are highly protective vaccines playing an effective role in the prevention of HPV 6, 11, 16, 18 which are responsible for CIN 1, CIN 2, and CIN 3.

Human Papillomavirus (HPV) Vaccine

Science.gov (United States)

Why get vaccinated?HPV vaccine prevents infection with human papillomavirus (HPV) types that are associated with cause ... at http://www.cdc.gov/hpv. HPV Vaccine (Human Papillomavirus) Information Statement. U.S. Department of Health and ...

Comparison of Real-Time Multiplex Human Papillomavirus (HPV) PCR Assays with INNO-LiPA HPV Genotyping Extra Assay▿

OpenAIRE

Else, Elizabeth A.; Swoyer, Ryan; Zhang, Yuhua; Taddeo, Frank J.; Bryan, Janine T.; Lawson, John; Van Hyfte, Inez; Roberts, Christine C.

2011-01-01

Real-time type-specific multiplex human papillomavirus (HPV) PCR assays were developed to detect HPV DNA in samples collected for the efficacy determination of the quadrivalent HPV (type 6, 11, 16, and 18) L1 virus-like particle (VLP) vaccine (Gardasil). Additional multiplex (L1, E6, and E7 open reading frame [ORF]) or duplex (E6 and E7 ORF) HPV PCR assays were developed to detect high-risk HPV types, including HPV type 31 (HPV31), HPV33, HPV35, HPV39, HPV45, HPV51, HPV52, HPV56, HPV58, and H...

Morphoproteomics, E6/E7 in-situ hybridization, and biomedical analytics define the etiopathogenesis of HPV-associated oropharyngeal carcinoma and provide targeted therapeutic options.

Science.gov (United States)

Brown, Robert E; Naqvi, Syed; McGuire, Mary F; Buryanek, Jamie; Karni, Ron J

2017-08-17

Human papillomavirus (HPV) has been identified as an etiopathogenetic factor in oropharyngeal squamous cell carcinoma. The HPV E6 and E7 oncogenes are instrumental in promoting proliferation and blocking differentiation leading to tumorigenesis. Although surgical intervention can remove such tumors, the potential for an etiologic field effect with recurrent disease is real. A downstream effector of E7 oncoprotein, enhancer of zeste homolog 2 (EZH2), is known to promote proliferation and to pose a block in differentiation and in turn, could lead to HPV-induced malignant transformation. However, the EZH2 pathway is amenable to low toxicity therapies designed to promote differentiation to a more benign state and prevent recurrent disease by inhibiting the incorporation of HPV into the genome. This is the first study using clinical specimens to demonstrate EZH2 protein expression in oropharyngeal carcinoma (OPC). The study included eight patients with oropharyngeal carcinoma, confirmed p16INK4a- positive by immunohistochemistry (IHC). The tissue expression of E6/E7 messenger RNA (mRNA) was measured by RNAscope® in-situ hybridization technology. Expression of EZH2, Ki-67, and mitotic indices were assessed by morphoproteomic analysis. Biomedical analytics expanded the results with data from Ingenuity Pathway Analysis (IPA) and KEGG databases to construct a molecular network pathway for further insights. Expression of E6 and E7 oncogenes in p16INK4a- positive oropharyngeal carcinoma was confirmed. EZH2 and its correlates, including elevated proliferation index (Ki-67) and mitotic progression were also present. Biomedical analytics validated the relationship between HPV- E6 and E7 and the expression of the EZH2 pathway. There is morphoproteomic and mRNA evidence of the association of p16INK4a-HPV infection with the E6 and E7 oncogenes and the expression of EZH2, Ki-67 and mitotic progression in oropharyngeal carcinoma. The molecular network biology was confirmed by

Human papillomavirus E6/E7 oncogenes promote mouse ear regeneration by increasing the rate of wound re-epithelization and epidermal growth.

Science.gov (United States)

Valencia, Concepción; Bonilla-Delgado, José; Oktaba, Katarzyna; Ocádiz-Delgado, Rodolfo; Gariglio, Patricio; Covarrubias, Luis

2008-12-01

Mammals have limited regeneration capacity. We report here that, in transgenic mice (Tg(bK6-E6/E7)), the expression of the E6/E7 oncogenes of human papilloma virus type 16 (HPV16) under the control of the bovine keratin 6 promoter markedly improves the mouse's capacity to repair portions of the ear after being wounded. Increased repair capacity correlates with an increased number of epidermal proliferating cells. In concordance with the expected effects of the E6 and E7 oncogenes, levels of p53 decreased and those of p16 in epidermal cells increased. In addition, we observed that wound re-epithelization proceeded faster in transgenic than in wild-type animals. After the initial re-epithelization, epidermal cell migration from the intact surrounding tissue appears to be a major contributor to the growing epidermis, especially in the repairing tissue of transgenic mice. We also found that there is a significantly higher number of putative epidermal stem cells in Tg(bK6-E6/E7) than in wild-type mice. Remarkably, hair follicles and cartilage regenerated within the repaired ear tissue, without evidence of tumor formation. We propose that the ability to regenerate ear portions is limited by the capacity of the epidermis to repair itself and grow.

Nucleotide sequences of cDNAs for human papillomavirus type 18 transcripts in HeLa cells

International Nuclear Information System (INIS)

Inagaki, Yutaka; Tsunokawa, Youko; Takebe, Naoko; Terada, Masaaki; Sugimura, Takashi; Nawa, Hiroyuki; Nakanishi, Shigetada

1988-01-01

HeLa cells expressed 3.4- and 1.6-kilobase (kb) transcripts of the integrated human papillomavirus (HPV) type 18 genome. Two types of cDNA clones representing each size of HPV type 18 transcript were isolated. Sequence analysis of these two types of cDNA clones revealed that the 3.4-kb transcript contained E6, E7, the 5' portion of E1, and human sequence and that the 1.6-kb transcript contained spliced and frameshifted E6 (E6 * ), E7, and human sequence. There was a common human sequence containing a poly(A) addition signal in the 3' end portions of both transcripts, indicating that they were transcribed from the HPV genome at the same integration site with different splicing. Furthermore, the 1.6-kb transcript contained both of the two viral TATA boxes upstream of E6, strongly indicating that a cellular promoter was used for its transcription

Rapid enrichment of human papillomavirus (HPV)-specific polyclonal T cell populations for adoptive immunotherapy of cervical cancer

NARCIS (Netherlands)

de Jong, Annemieke; van der Hulst, Jeanette M.; Kenter, Gemma G.; Drijfhout, Jan Wouter; Franken, Kees L. M. C.; Vermeij, Pieter; Offringa, Rienk; van der Burg, Sjoerd H.; Melief, Cornelis J. M.

2005-01-01

The majority of cervical cancers are caused by human papillomavirus type 16 (HPV16). Cervical cancer is associated with an ineffective host immune response against the HPV16 oncoproteins, characterized by the lack of the strong E6-specific T-helper type 1 (Th1) immunity that is generally present in

Frequency of human papillomavirus infection in patients with gastrointestinal cancer.

Science.gov (United States)

Roesch-Dietlen, F; Cano-Contreras, A D; Sánchez-Maza, Y J; Espinosa-González, J M; Vázquez-Prieto, M Á; Valdés-de la O, E J; Díaz-Roesch, F; Carrasco-Arroniz, M Á; Cruz-Palacios, A; Grube-Pagola, P; Sumoza-Toledo, A; Vivanco-Cid, H; Mellado-Sánchez, G; Meixueiro-Daza, A; Silva-Cañetas, C S; Carrillo-Toledo, M G; Lagunes-Torres, R; Amieva-Balmori, M; Gómez-Castaño, P C; Reyes-Huerta, J U; Remes-Troche, J M

2018-02-15

Cancer is the result of the interaction of genetic and environmental factors. It has recently been related to viral infections, one of which is human papillomavirus. The aim of the present study was to describe the frequency of human papillomavirus infection in patients with digestive system cancers. A prospective, multicenter, observational study was conducted on patients with gastrointestinal cancer at 2public healthcare institutes in Veracruz. Two tumor samples were taken, one for histologic study and the other for DNA determination of human papillomavirus and its genotypes. Anthropometric variables, risk factors, sexual habits, tumor location, and histologic type of the cancer were analyzed. Absolute and relative frequencies were determined using the SPSS version 24.0 program. Fifty-three patients were studied. They had gastrointestinal cancer located in: the colon (62.26%), stomach (18.87%), esophagus (7.55%), rectum (7.55%), and small bowel (3.77%). Human papillomavirus was identified in 11.32% of the patients, 66.7% of which corresponded to squamous cell carcinoma and 33.3% to adenocarcinoma. Only genotype 18 was identified. Mean patient age was 61.8±15.2 years, 56.60% of the patients were men, and 43.40% were women. A total of 15.8% of the patients had a family history of cancer and 31.6% had a personal history of the disease, 38.6% were tobacco smokers, and 61.4% consumed alcohol. Regarding sex, 5.3% of the patients said they were homosexual, 3.5% were bisexual, 29.8% engaged in oral sex, and 24.6% in anal sex. Our study showed that human papillomavirus infection was a risk factor for the development of gastrointestinal cancer, especially of squamous cell origin. Copyright © 2018 Asociación Mexicana de Gastroenterología. Publicado por Masson Doyma México S.A. All rights reserved.

E6D25E, HPV16 Asian variant shows specific proteomic pattern correlating in cells transformation and suppressive innate immune response

International Nuclear Information System (INIS)

Chopjitt, Peechanika; Pientong, Chamsai; Sunthamala, Nuchsupha; Kongyingyoes, Bunkerd; Haonon, Ornuma; Boonmars, Thidarut; Kikawa, Satomi; Nakahara, Tomomi; Kiyono, Tohru; Ekalaksananan, Tipaya

2016-01-01

HPV16 Asian variant (HPV16As) containing E6D25E oncogene, is commonly associated with cervical cancers of Asian populations. To explore a mechanism of E6D25E oncoprotein in carcinogenesis, we compared protein profiles in human keratinocytes expressing E6D25E with E6 of HPV16 prototype (E6Pro). A human cervical keratinocyte cell line, HCK1T, was transduced with retroviruses containing E6D25E or E6Pro genes. Biological properties of E6D25E or E6Pro transduced HCK1T cells were characterized. Protein profiles of the transduced HCK1T cells were analyzed using 2D-PAGE and characterized by mass spectrometry and western blotting. Reactomes of modulated proteins were analyzed by using the Reactome Knowledgebase. The E6D25E and E6Pro oncoproteins were comparable for their abilities to degrade p53 and suppress the induction of p21, and induce cell proliferation. Interestingly, the protein profiles of the HCK1T cells transduced with E6D25E showed specific proteomic patterns different from those with E6Pro. Among altered proteins, more than 1.5-fold up- or down- regulation was observed in E6D25E-expressing cells for gp96 and keratin7 which involved in activation of TLR signaling and transformation of squamocolumnar junction cells, respectively. This report describes new cellular proteins specifically targeted by E6D25E oncoprotein that may contribute to impair immune response against viral infection and cell transformation associated with oncogenic property of HPV16As variant. - Highlights: • E6D25E HPV16 specifically modulates protein profile of human keratinocytes. • E6D25E HPV16 modulates protein profile which involves in TLR signalling and transformation of squamocolumnar junction cells. • E6D25E oncoprotein may correlate to impair of immune response against viral infection and cells transformation.

E6D25E, HPV16 Asian variant shows specific proteomic pattern correlating in cells transformation and suppressive innate immune response

Energy Technology Data Exchange (ETDEWEB)

Chopjitt, Peechanika; Pientong, Chamsai; Sunthamala, Nuchsupha [Department of Microbiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, 40002 (Thailand); HPV & EBV and Carcinogenesis Research Group, Khon Kaen University (Thailand); Kongyingyoes, Bunkerd [Department of Pharmacology, Faculty of Medicine, Khon Kaen University, Khon Kaen, 40002 (Thailand); Haonon, Ornuma; Boonmars, Thidarut [Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen, 40002 (Thailand); Kikawa, Satomi; Nakahara, Tomomi [Division of Carcinogenesis and Cancer Prevention, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045 (Japan); Kiyono, Tohru, E-mail: tkiyono@ncc.go.jp [Division of Carcinogenesis and Cancer Prevention, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045 (Japan); Ekalaksananan, Tipaya, E-mail: tipeka@kku.ac.th [Department of Microbiology, Faculty of Medicine, Khon Kaen University, Khon Kaen, 40002 (Thailand); HPV & EBV and Carcinogenesis Research Group, Khon Kaen University (Thailand)

2016-09-09

HPV16 Asian variant (HPV16As) containing E6D25E oncogene, is commonly associated with cervical cancers of Asian populations. To explore a mechanism of E6D25E oncoprotein in carcinogenesis, we compared protein profiles in human keratinocytes expressing E6D25E with E6 of HPV16 prototype (E6Pro). A human cervical keratinocyte cell line, HCK1T, was transduced with retroviruses containing E6D25E or E6Pro genes. Biological properties of E6D25E or E6Pro transduced HCK1T cells were characterized. Protein profiles of the transduced HCK1T cells were analyzed using 2D-PAGE and characterized by mass spectrometry and western blotting. Reactomes of modulated proteins were analyzed by using the Reactome Knowledgebase. The E6D25E and E6Pro oncoproteins were comparable for their abilities to degrade p53 and suppress the induction of p21, and induce cell proliferation. Interestingly, the protein profiles of the HCK1T cells transduced with E6D25E showed specific proteomic patterns different from those with E6Pro. Among altered proteins, more than 1.5-fold up- or down- regulation was observed in E6D25E-expressing cells for gp96 and keratin7 which involved in activation of TLR signaling and transformation of squamocolumnar junction cells, respectively. This report describes new cellular proteins specifically targeted by E6D25E oncoprotein that may contribute to impair immune response against viral infection and cell transformation associated with oncogenic property of HPV16As variant. - Highlights: • E6D25E HPV16 specifically modulates protein profile of human keratinocytes. • E6D25E HPV16 modulates protein profile which involves in TLR signalling and transformation of squamocolumnar junction cells. • E6D25E oncoprotein may correlate to impair of immune response against viral infection and cells transformation.

Degradation of Human PDZ-Proteins by Human Alphapapillomaviruses Represents an Evolutionary Adaptation to a Novel Cellular Niche

Science.gov (United States)

Van Doorslaer, Koenraad; DeSalle, Rob; Einstein, Mark H.; Burk, Robert D.

2015-01-01

In order to complete their life cycle, papillomaviruses have evolved to manipulate a plethora of cellular pathways. The products of the human Alphapapillomavirus E6 proteins specifically interact with and target PDZ containing proteins for degradation. This viral phenotype has been suggested to play a role in viral oncogenesis. To analyze the association of HPV E6 mediated PDZ-protein degradation with cervical oncogenesis, a high-throughput cell culture assay was developed. Degradation of an epitope tagged human MAGI1 isoform was visualized by immunoblot. The correlation between HPV E6-induced degradation of hMAGI1 and epidemiologically determined HPV oncogenicity was evaluated using a Bayesian approach within a phylogenetic context. All tested oncogenic types degraded the PDZ-containing protein hMAGI1d; however, E6 proteins isolated from several related albeit non-oncogenic viral types were equally efficient at degrading hMAGI1. The relationship between both traits (oncogenicity and PDZ degradation potential) is best explained by a model in which the potential to degrade PDZ proteins was acquired prior to the oncogenic phenotype. This analysis provides evidence that the ancestor of both oncogenic and non-oncogenic HPVs acquired the potential to degrade human PDZ-containing proteins. This suggests that HPV E6 directed degradation of PDZ-proteins represents an ancient ecological niche adaptation. Phylogenetic modeling indicates that this phenotype is not specifically correlated with oncogenic risk, but may act as an enabling phenotype. The role of PDZ protein degradation in HPV fitness and oncogenesis needs to be interpreted in the context of Alphapapillomavirus evolution. PMID:26086730

Degradation of Human PDZ-Proteins by Human Alphapapillomaviruses Represents an Evolutionary Adaptation to a Novel Cellular Niche.

Directory of Open Access Journals (Sweden)

Koenraad Van Doorslaer

2015-06-01

Full Text Available In order to complete their life cycle, papillomaviruses have evolved to manipulate a plethora of cellular pathways. The products of the human Alphapapillomavirus E6 proteins specifically interact with and target PDZ containing proteins for degradation. This viral phenotype has been suggested to play a role in viral oncogenesis. To analyze the association of HPV E6 mediated PDZ-protein degradation with cervical oncogenesis, a high-throughput cell culture assay was developed. Degradation of an epitope tagged human MAGI1 isoform was visualized by immunoblot. The correlation between HPV E6-induced degradation of hMAGI1 and epidemiologically determined HPV oncogenicity was evaluated using a Bayesian approach within a phylogenetic context. All tested oncogenic types degraded the PDZ-containing protein hMAGI1d; however, E6 proteins isolated from several related albeit non-oncogenic viral types were equally efficient at degrading hMAGI1. The relationship between both traits (oncogenicity and PDZ degradation potential is best explained by a model in which the potential to degrade PDZ proteins was acquired prior to the oncogenic phenotype. This analysis provides evidence that the ancestor of both oncogenic and non-oncogenic HPVs acquired the potential to degrade human PDZ-containing proteins. This suggests that HPV E6 directed degradation of PDZ-proteins represents an ancient ecological niche adaptation. Phylogenetic modeling indicates that this phenotype is not specifically correlated with oncogenic risk, but may act as an enabling phenotype. The role of PDZ protein degradation in HPV fitness and oncogenesis needs to be interpreted in the context of Alphapapillomavirus evolution.

Degradation of Human PDZ-Proteins by Human Alphapapillomaviruses Represents an Evolutionary Adaptation to a Novel Cellular Niche.

Science.gov (United States)

Van Doorslaer, Koenraad; DeSalle, Rob; Einstein, Mark H; Burk, Robert D

2015-06-01

In order to complete their life cycle, papillomaviruses have evolved to manipulate a plethora of cellular pathways. The products of the human Alphapapillomavirus E6 proteins specifically interact with and target PDZ containing proteins for degradation. This viral phenotype has been suggested to play a role in viral oncogenesis. To analyze the association of HPV E6 mediated PDZ-protein degradation with cervical oncogenesis, a high-throughput cell culture assay was developed. Degradation of an epitope tagged human MAGI1 isoform was visualized by immunoblot. The correlation between HPV E6-induced degradation of hMAGI1 and epidemiologically determined HPV oncogenicity was evaluated using a Bayesian approach within a phylogenetic context. All tested oncogenic types degraded the PDZ-containing protein hMAGI1d; however, E6 proteins isolated from several related albeit non-oncogenic viral types were equally efficient at degrading hMAGI1. The relationship between both traits (oncogenicity and PDZ degradation potential) is best explained by a model in which the potential to degrade PDZ proteins was acquired prior to the oncogenic phenotype. This analysis provides evidence that the ancestor of both oncogenic and non-oncogenic HPVs acquired the potential to degrade human PDZ-containing proteins. This suggests that HPV E6 directed degradation of PDZ-proteins represents an ancient ecological niche adaptation. Phylogenetic modeling indicates that this phenotype is not specifically correlated with oncogenic risk, but may act as an enabling phenotype. The role of PDZ protein degradation in HPV fitness and oncogenesis needs to be interpreted in the context of Alphapapillomavirus evolution.

Karyopherin β3: A new cellular target for the HPV-16 E5 oncoprotein

International Nuclear Information System (INIS)

Krawczyk, Ewa; Hanover, John A.; Schlegel, Richard; Suprynowicz, Frank A.

2008-01-01

Epidemiological and experimental studies have shown that high-risk human papillomaviruses (HPVs) are the causative agents of cervical cancer worldwide, and that HPV-16 is associated with more than half of these cases. In addition to the well-characterized E6 and E7 oncoproteins of HPV-16, recent evidence increasingly has implicated the HPV-16 E5 protein (16E5) as an important mediator of oncogenic transformation. Since 16E5 has no known intrinsic enzymatic activity, its effects on infected cells are most likely mediated by interactions with various cellular proteins and/or its documented association with lipid rafts. In the present study, we describe a new cellular target that binds to 16E5 in COS cells and in stable human ectocervical cell lines. This target is karyopherin β3, a member of the nuclear import receptor family with critical roles in the nuclear import of ribosomal proteins and in the secretory pathway

An Overview of Quadrivalent Human Papillomavirus Vaccine Safety

DEFF Research Database (Denmark)

Vichnin, Michelle; Bonanni, Paolo; Klein, Nicola P

2015-01-01

BACKGROUND: A quadrivalent human papillomavirus (HPV4) type 6/11/16/18 vaccine (GARDASIL/SILGARD®) has been licensed in many countries around the world for the prevention of cervical, vulvar, vaginal, and anal cancers and precancers, as well as external genital warts causally related to HPV types 6...

Allergenic relevance of nonspecific lipid transfer proteins 2: Identification and characterization of Api g 6 from celery tuber as representative of a novel IgE-binding protein family.

Science.gov (United States)

Vejvar, Eva; Himly, Martin; Briza, Peter; Eichhorn, Stephanie; Ebner, Christof; Hemmer, Wolfgang; Ferreira, Fatima; Gadermaier, Gabriele

2013-11-01

Apium graveolens represents a relevant food allergen source linked with severe systemic reactions. We sought to identify an IgE-binding nonspecific lipid transfer protein (nsLTP) in celery tuber. A low molecular weight protein exclusively present in celery tuber was purified and designated Api g 6. The entire protein sequence was obtained by MS and classified as member of the nsLTP2 family. Api g 6 is monomeric in solution with a molecular mass of 6936 Da. The alpha-helical disulfide bond-stabilized structure confers tremendous thermal stability (Tm > 90°C) and high resistance to gastrointestinal digestion. Endolysosomal degradation demonstrated low susceptibility and the presence of a dominant peptide cluster at the C-terminus. Thirty-eight percent of A. graveolens allergic patients demonstrated IgE reactivity to purified natural Api g 6 in ELISA and heat treatment did only partially reduce its allergenic activity. No correlation in IgE binding and limited cross-reactivity was observed with Api g 2 and Art v 3, nsLTP1 from celery stalks and mugwort pollen. Api g 6, a novel nsLTP2 from celery tuber represents the first well-characterized allergen in this protein family. Despite similar structural and physicochemical features as nsLTP1, immunological properties of Api g 6 are distinct which warrants its inclusion in molecule-based diagnosis of A. graveolens allergy. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Cell-mediated immune response: a clinical review of the therapeutic potential of human papillomavirus vaccination.

Science.gov (United States)

Meyer, Sonja Izquierdo; Fuglsang, Katrine; Blaakaer, Jan

2014-12-01

This clinical review aims to assess the efficacy of human papillomavirus 16/18 (HPV16/18) vaccination on the cell-mediated immune response in women with existing cervical intraepithelial neoplasia or cervical cancer induced by HPV16 or HPV18. A focused and thorough literature search conducted in five different databases found 996 publications. Six relevant articles were chosen for further review. In total, 154 patients (>18 years of age) were enrolled in prospective study trials with 3-15 months of follow up. The vaccine applications were administered two to four times. The vaccines contained different combinations of HPV16 and HPV18 and early proteins, E6 and E7. The primary outcome was the cell-mediated immune response. Correlation to clinical outcome (histopathology) and human leukocyte antigen genes were secondary endpoints. All vaccines triggered a detectable cell-mediated immune response, some of which were statistically significant. Correlations between immunological response and clinical outcome (histopathology) were not significant, so neoplasms may not be susceptible to vaccine-generated cytotoxic T cells (CD8(+)). Prophylactic HPV vaccines have been introduced to reduce the incidence of cervical cancer in young women. Women already infected with HPV could benefit from a therapeutic HPV vaccination. Hence, it is important to continue the development of therapeutic HPV vaccines to lower the rate of HPV-associated malignancies and crucial to evaluate vaccine efficacy clinically. This clinical review represents an attempt to elucidate the theories supporting the development of an HPV vaccine with a therapeutic effect on human papillomavirus-induced malignancies of the cervix. © 2014 Nordic Federation of Societies of Obstetrics and Gynecology.

Direct binding of retromer to human papillomavirus type 16 minor capsid protein L2 mediates endosome exit during viral infection.

Directory of Open Access Journals (Sweden)

Andreea Popa

2015-02-01

Full Text Available Trafficking of human papillomaviruses to the Golgi apparatus during virus entry requires retromer, an endosomal coat protein complex that mediates the vesicular transport of cellular transmembrane proteins from the endosome to the Golgi apparatus or the plasma membrane. Here we show that the HPV16 L2 minor capsid protein is a retromer cargo, even though L2 is not a transmembrane protein. We show that direct binding of retromer to a conserved sequence in the carboxy-terminus of L2 is required for exit of L2 from the early endosome and delivery to the trans-Golgi network during virus entry. This binding site is different from known retromer binding motifs and can be replaced by a sorting signal from a cellular retromer cargo. Thus, HPV16 is an unconventional particulate retromer cargo, and retromer binding initiates retrograde transport of viral components from the endosome to the trans-Golgi network during virus entry. We propose that the carboxy-terminal segment of L2 protein protrudes through the endosomal membrane and is accessed by retromer in the cytoplasm.

Heat Increases the Editing Efficiency of Human Papillomavirus E2 Gene by Inducing Upregulation of APOBEC3A and 3G.

Science.gov (United States)

Yang, Yang; Wang, Hexiao; Zhang, Xinrui; Huo, Wei; Qi, Ruiqun; Gao, Yali; Zhang, Gaofeng; Song, Bing; Chen, Hongduo; Gao, Xinghua

2017-04-01

Apolipoprotein B mRNA-editing catalytic polypeptide (APOBEC) 3 proteins have been identified as potent viral DNA mutators and have broad antiviral activity. In this study, we demonstrated that apolipoprotein B mRNA-editing catalytic polypeptide 3A (A3A) and A3G expression levels were significantly upregulated in human papillomavirus (HPV)-infected cell lines and tissues. Heat treatment resulted in elevated expression of A3A and A3G in a temperature-dependent manner in HPV-infected cells. Correspondingly, HPV-infected cells heat-treated at 44 °C showed accumulated G-to-A or C-to-T mutation in HPV E2 gene. Knockdown of A3A or A3G could promote cell viability, along with the lower frequency of A/T in HPV E2 gene. In addition, regressing genital viral warts also harbored high G-to-A or C-to-T mutation in HPV E2 gene. Taken together, we demonstrate that apolipoprotein B mRNA-editing catalytic polypeptide 3 expression and editing function was heat sensitive to a certain degree, partly explaining the mechanism of action of local hyperthermia to treat viral warts. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Requirement for the eIF4E binding proteins for the synergistic down-regulation of protein synthesis by hypertonic conditions and mTOR inhibition.

Science.gov (United States)

Clemens, Michael J; Elia, Androulla; Morley, Simon J

2013-01-01

The protein kinase mammalian target of rapamycin (mTOR) regulates the phosphorylation and activity of several proteins that have the potential to control translation, including p70S6 kinase and the eIF4E binding proteins 4E-BP1 and 4E-BP2. In spite of this, in exponentially growing cells overall protein synthesis is often resistant to mTOR inhibitors. We report here that sensitivity of wild-type mouse embryonic fibroblasts (MEFs) to mTOR inhibitors can be greatly increased when the cells are subjected to the physiological stress imposed by hypertonic conditions. In contrast, protein synthesis in MEFs with a double knockout of 4E-BP1 and 4E-BP2 remains resistant to mTOR inhibitors under these conditions. Phosphorylation of p70S6 kinase and protein kinase B (Akt) is blocked by the mTOR inhibitor Ku0063794 equally well in both wild-type and 4E-BP knockout cells, under both normal and hypertonic conditions. The response of protein synthesis to hypertonic stress itself does not require the 4E-BPs. These data suggest that under certain stress conditions: (i) translation has a greater requirement for mTOR activity and (ii) there is an absolute requirement for the 4E-BPs for regulation by mTOR. Importantly, dephosphorylation of p70S6 kinase and Akt is not sufficient to affect protein synthesis acutely.

The adenovirus E4 11 k protein binds and relocalizes the cytoplasmic P-body component Ddx6 to aggresomes

International Nuclear Information System (INIS)

Greer, Amy E.; Hearing, Patrick; Ketner, Gary

2011-01-01

The adenovirus E4 11 k protein, product of E4 ORF3, is required in infection for processes including normal accumulation of viral late mRNAs. 11 k restructures both the nucleus and cytoplasm of infected cells by relocalizing specific host cell target proteins, most strikingly components of nuclear PML oncogenic domains. It is likely that in many cases relocalization inactivates target proteins to produce 11 k's effects, although the mechanism and targets for stimulation of late mRNA accumulation is unknown. We have identified a new set of proteins relocalized by 11 k: at least five protein components of cytoplasmic mRNA processing bodies (p-bodies) are found in 11 k-induced cytoplasmic aggresomes, sites where proteins are inactivated or destroyed. One of these p-body proteins, RNA helicase Ddx6, binds 11 k, suggesting a mechanism for relocalization. Because p-bodies are sites for mRNA degradation, their modification by 11 k may provide an explanation for the role of 11 k in viral late mRNA accumulation.

Observations on the expression of human papillomavirus major capsid protein in HeLa cells.

Science.gov (United States)

Xiao, Chang-Yi; Fu, Bing-Bing; Li, Zhi-Ying; Mushtaq, Gohar; Kamal, Mohammad Amjad; Li, Jia-Hua; Tang, Gui-Cheng; Xiao, Shuo-Shuang

2015-01-01

The goal of this study was to identify the nature of the inclusion bodies that have been found in HeLa cells (cervical cancer immortal cell line) by electron microscope and to determine whether the major capsid protein (L1) of human papillomavirus (HPV) can be expressed in HPV-positive uterine cervix cancer cells. HPV L1 protein expression in HeLa cells was detected with anti-HPV L1 multivalent mice monoclonal antibody and rabbit polyclonal anti-HPV L1 antibody by ELISA, light microscope immunohistochemistry, electron microscope immunocytochemistry and Western blotting assays. Reverse transcriptional PCR (RT-PCR) was performed to detect the transcription of L1 mRNA in HeLa cells. The immortalized human keratinocyte HeCat was used as the negative control. HPV L1 proteins reacted positively in the lysate of HeLa cells by ELISA assays. HRP labeled light microscope immunohistochemistry assay showed that there was a strong HPV L1 positive reaction in HeLa cells. Under the electron microscope, irregular shaped inclusion bodies, assembled by many small and uniform granules, had been observed in the cytoplasm of some HeLa cells. These granules could be labeled by the colloidal gold carried by HPV L1 antibody. The Western blotting assay showed that there was a L1 reaction strap at 80-85 kDa in the HeLa cell lysates, hence demonstrating the existence of HPV18 L1 in HeLa cells. RT-PCR assay showed that the L1 mRNA was transcribed in HeLa cells. The inclusion bodies found in the cytoplasm of HeLa cells are composed of HPV18 L1 protein. Since HeLa cell line is a type of cervical cancer cells, this implies that HeLa cells have the ability to express HPV L1 proteins.

Animal models of papillomavirus pathogenesis.

Science.gov (United States)

Campo, M Saveria

2002-11-01

Tumorigenesis due to papillomavirus (PV) infection was first demonstrated in rabbits and cattle early last century. Despite the evidence obtained in animals, the role of viruses in human cancer was dismissed as irrelevant. It took a paradigm shift in the late 1970s for some viruses to be recognised as 'tumour viruses' in humans, and in 1995, more than 60 years after Rous's first demonstration of CRPV oncogenicity, WHO officially declared that 'HPV-16 and HPV-18 are carcinogenic to humans'. Experimental studies with animal PVs have been a determining factor in this decision. Animal PVs have been studied both as agents of disease in animals and as models of human PV infection. In addition to the study of PV infection in whole animals, in vitro studies with animal PV proteins have contributed greatly to the understanding of the mechanisms of cell transformation. Animal PVs cause distressing diseases in both farm and companion animals, such as teat papillomatosis in cattle, equine sarcoids and canine oral papillomatosis and there is an urgent need to understand the pathogenesis of these problematic infections. Persistent and florid teat papillomatosis in cows can lead to mastitis, prevent the suckling of calves and make milking impossible; heavily affected animals are culled and so occasionally are whole herds. Equine sarcoids are often recurrent and untreatable and lead to loss of valuable animals. Canine oral papillomatosis can be very extensive and persistent and lead to great distress. Thus the continuing research in the biology of animal PVs is amply justified. BPVs and CRPV have been for many years the model systems with which to study the biology of HPV. Induction of papillomas and their neoplastic progression has been experimentally demonstrated and reproduced in cattle and rabbits, and virus-cofactor interactions have been elucidated in these systems. With the advancements in molecular and cell culture techniques, the direct study of HPV has become less

Role of high-risk human papillomavirus in the etiology of oral and oropharyngeal cancers in Thailand: A case-control study.

Science.gov (United States)

Chotipanich, Adit; Siriarechakul, Surattaya; Mungkung, On-Ong

2018-01-01

Among developing countries, Thailand shows no increase in the incidence of human papillomavirus-driven oropharyngeal cancer. The causal role of human papillomavirus infection in this pathology has not been researched thoroughly. A hospital-based, case-control study was performed which included 104 patients with newly diagnosed oral and oropharyngeal squamous cell carcinomas and 104 individuals without cancer. The Cervista high-risk human papillomavirus and 16/18 assays were used to detect human papillomavirus. Odds ratios were used to assess the association between high-risk genotypes of human papillomavirus and the cancers. High-risk human papillomavirus was detected in 4 of 52 (7.7%) oral cancer cases, 6 of 52 (11.5%) oropharyngeal cancer cases, and 1 of 104 (0.96%) control subjects. Of 104 cancer patients in the study, 83 were smokers. High-risk human papillomavirus was significantly associated with oropharyngeal cancer (odds ratio = 13.44, 95% confidence interval = 1.6-114.8) but was nonsignificantly associated with oral cancer (odds ratio = 8.58, 95% confidence interval = 0.9-78.9). However, after adjustment for smoking, high-risk human papillomavirus was determined to be nonsignificantly associated with oropharyngeal cancer (adjusted odds ratio = 5.83, 95% confidence interval = 0.8-43.5). Although low human papillomavirus prevalence was observed, the rate of high-risk human papillomavirus infection in the cancer group was still higher than that in the control group. Smoking may have an influence on the etiology of human papillomavirus-related cancers. However, the study is underpowered to clarify the role of human papillomavirus as the independent risk factor for oral and oropharyngeal cancers in the Thai population.

Detection of human papillomavirus type 6/11 DNA in conjunctival papillomas by in situ hybridization with radioactive probes

International Nuclear Information System (INIS)

McDonnell, P.J.; McDonnell, J.M.; Kessis, T.; Green, W.R.; Shah, K.V.

1987-01-01

Twenty-three conjunctival papillomas and 28 conjunctival dysplasias were examined for human papillomavirus (HPV)-DNA sequences by in situ hybridization with nick-translated 35 S-labeled HPV probes. Adjacent paraffin sections were hybridized with HPV type 2, 6, 16, and 18 probes at Tm - 17 degrees C. Fifteen tissues, all papillomas, displayed positive hybridization with the HPV-6 probe. Infection with HPV-6 (or the closely related HPV-11) appeared to be responsible for most of the conjunctival papillomas of children and young adults. The presence of genital tract HPV-6 in these lesions suggests that some of the infections were acquired during passage through an infected birth canal. The lack of hybridization in adult conjunctival dysplasias indicates either that HPVs are not associated with this condition or that the probes and the technique utilized were not adequate for demonstration of this association

First New World Primate Papillomavirus Identification in the Atlantic Forest, Brazil: Alouatta guariba papillomavirus 1.

Science.gov (United States)

Silvestre, Rodrigo Vellasco Duarte; de Souza, Alex Junior Souza; Júnior, Edivaldo Costa Sousa; Silva, Allan Kaio; de Mello, Wyller Alencar; Nunes, Marcio Roberto T; Júnior, João Lídio S G V; Cardoso, Jedson Ferreira; de Vasconcelos, Janaina Mota; de Oliveira, Layanna Freitas; da Silva, Sandro Patroca; da Silva, Adriana Marques J; Fries, Brigida Gomes; Summa, Maria Eugênia L; de Sá, Lilian Rose M

2016-08-18

We report here the complete genome sequence of the first papillomavirus detected in a New World primate, howler monkey, Alouatta guariba clamitans papillomavirus 1 (AgPV1), from the Atlantic Forest in São Paulo State, Brazil. Copyright © 2016 Silvestre et al.

hpvPDB: An Online Proteome Reserve for Human Papillomavirus

Directory of Open Access Journals (Sweden)

Satish Kumar

2013-12-01

Full Text Available Human papillomavirus (HPV infection is the leading cause of cancer mortality among women worldwide. The molecular understanding of HPV proteins has significant connotation for understanding their intrusion in the host and designing novel protein vaccines and anti-viral agents, etc. Genomic, proteomic, structural, and disease-related information on HPV is available on the web; yet, with trivial annotations and more so, it is not well customized for data analysis, host-pathogen interaction, strain-disease association, drug designing, and sequence analysis, etc. We attempted to design an online reserve with comprehensive information on HPV for the end users desiring the same. The Human Papillomavirus Proteome Database (hpvPDB domiciles proteomic and genomic information on 150 HPV strains sequenced to date. Simultaneous easy expandability and retrieval of the strain-specific data, with a provision for sequence analysis and exploration potential of predicted structures, and easy access for curation and annotation through a range of search options at one platform are a few of its important features. Affluent information in this reserve could be of help for researchers involved in structural virology, cancer research, drug discovery, and vaccine design.

Evidence of recombination and positive selection in cetacean papillomaviruses

International Nuclear Information System (INIS)

Robles-Sikisaka, Refugio; Rivera, Rebecca; Nollens, Hendrik H.; St Leger, Judy; Durden, Wendy N.; Stolen, Megan; Burchell, Jennifer; Wellehan, James F.X.

2012-01-01

Papillomaviruses (PVs) are small DNA viruses that have been associated with increased epithelial proliferation. Over one hundred PV types have been identified in humans; however, only three have been identified in bottlenose dolphins (Tursiops truncatus) to date. Using rolling circle amplification and degenerate PCR, we identified four novel PV genomes of bottlenose dolphins. TtPV4, TtPV5 and TtPV6 were identified in genital lesions while TtPV7 was identified in normal genital mucosa. Bayesian analysis of the full-length L1 genes found that TtPV4 and TtPV7 group within the Upsilonpapillomavirus genus while TtPV5 and TtPV6 group with Omikronpapillomavirus. However, analysis of the E1 gene did not distinguish these genera, implying that these genes may not share a common history, consistent with recombination. Recombination analyses identified several probable events. Signals of positive selection were found mostly in the E1 and E2 genes. Recombination and diversifying selection pressures constitute important driving forces of cetacean PV evolution.

Evidence of recombination and positive selection in cetacean papillomaviruses

Energy Technology Data Exchange (ETDEWEB)

Robles-Sikisaka, Refugio, E-mail: refugio.robles1@gmail.com [Hubbs-SeaWorld Research Institute, Center for Marine Veterinary Virology, 2595 Ingraham Street, San Diego, CA 92109 (United States); Rivera, Rebecca, E-mail: RRivera@hswri.org [Hubbs-SeaWorld Research Institute, Center for Marine Veterinary Virology, 2595 Ingraham Street, San Diego, CA 92109 (United States); Nollens, Hendrik H., E-mail: Hendrik.Nollens@SeaWorld.com [Hubbs-SeaWorld Research Institute, Center for Marine Veterinary Virology, 2595 Ingraham Street, San Diego, CA 92109 (United States); College of Veterinary Medicine, University of Florida, PO Box 110885, Gainesville, FL 32611 (United States); SeaWorld San Diego, 500 SeaWorld Drive, San Diego, CA 92109 (United States); St Leger, Judy, E-mail: Judy.St.Leger@SeaWorld.com [SeaWorld San Diego, 500 SeaWorld Drive, San Diego, CA 92109 (United States); Durden, Wendy N., E-mail: WNoke@hswri.org [Hubbs-SeaWorld Research Institute, 3830 South Highway A1A 4-181, Melbourne Beach, FL 32951 (United States); Stolen, Megan, E-mail: MStolen@hswri.org [Hubbs-SeaWorld Research Institute, 3830 South Highway A1A 4-181, Melbourne Beach, FL 32951 (United States); Burchell, Jennifer, E-mail: JBurchell@hswri.org [Hubbs-SeaWorld Research Institute, Center for Marine Veterinary Virology, 2595 Ingraham Street, San Diego, CA 92109 (United States); Wellehan, James F.X., E-mail: WellehanJ@ufl.edu [College of Veterinary Medicine, University of Florida, PO Box 110885, Gainesville, FL 32611 (United States)

2012-06-05

Papillomaviruses (PVs) are small DNA viruses that have been associated with increased epithelial proliferation. Over one hundred PV types have been identified in humans; however, only three have been identified in bottlenose dolphins (Tursiops truncatus) to date. Using rolling circle amplification and degenerate PCR, we identified four novel PV genomes of bottlenose dolphins. TtPV4, TtPV5 and TtPV6 were identified in genital lesions while TtPV7 was identified in normal genital mucosa. Bayesian analysis of the full-length L1 genes found that TtPV4 and TtPV7 group within the Upsilonpapillomavirus genus while TtPV5 and TtPV6 group with Omikronpapillomavirus. However, analysis of the E1 gene did not distinguish these genera, implying that these genes may not share a common history, consistent with recombination. Recombination analyses identified several probable events. Signals of positive selection were found mostly in the E1 and E2 genes. Recombination and diversifying selection pressures constitute important driving forces of cetacean PV evolution.

A pooled analysis of continued prophylactic efficacy of quadrivalent human papillomavirus (Types 6/11/16/18) vaccine against high-grade cervical and external genital lesions

DEFF Research Database (Denmark)

Kjaer, Susanne K; Sigurdsson, Kristján; Iversen, Ole-Erik

2009-01-01

Quadrivalent human papillomavirus (HPV) vaccine has been shown to provide protection from HPV 6/11/16/18-related cervical, vaginal, and vulvar disease through 3 years. We provide an update on the efficacy of the quadrivalent HPV vaccine against high-grade cervical, vaginal, and vulvar lesions bas...

Mechanisms of virus immune evasion lead to development from chronic inflammation to cancer formation associated with human papillomavirus infection.

Science.gov (United States)

Senba, Masachika; Mori, Naoki

2012-10-02

Human papillomavirus (HPV) has developed strategies to escape eradication by innate and adaptive immunity. Immune response evasion has been considered an important aspect of HPV persistence, which is the main contributing factor leading to HPV-related cancers. HPV-induced cancers expressing viral oncogenes E6 and E7 are potentially recognized by the immune system. The major histocompatibility complex (MHC) class I molecules are patrolled by natural killer cells and CD8+ cytotoxic T lymphocytes, respectively. This system of recognition is a main target for the strategies of immune evasion deployed by viruses. The viral immune evasion proteins constitute useful tools to block defined stages of the MHC class I presentation pathway, and in this way HPV avoids the host immune response. The long latency period from initial infection to persistence signifies that HPV evolves mechanisms to escape the immune response. It has now been established that there are oncogenic mechanisms by which E7 binds to and degrades tumor suppressor Rb, while E6 binds to and inactivates tumor suppressor p53. Therefore, interaction of p53 and pRb proteins can give rise to an increased immortalization and genomic instability. Overexpression of NF-κB in cervical and penile cancers suggests that NF-κB activation is a key modulator in driving chronic inflammation to cancer. HPV oncogene-mediated suppression of NF-κB activity contributes to HPV escape from the immune system. This review focuses on the diverse mechanisms of the virus immune evasion with HPV that leads to chronic inflammation and cancer.

Clinicopathological aspects and prevalence of human papillomavirus in anal cancer

Directory of Open Access Journals (Sweden)

Marina Tayla Mesquita Aguiar

2014-04-01

desenvolvimento do câncer anal, incluindo idade maior que 50 anos, dieta pobre em fibras, fístulas anais crônicas, tabagismo, múltiplos parceiros, prática de intercurso anal, infecção pelo HIV e imunossupressão. Entretanto, a presença do Papilomavírus Humano (HPV representa o principal fator de risco para o desenvolvimento do câncer anal. O objetivo deste estudo consistiu em avaliar os aspectos clínico-patológicos de uma série de pacientes com carcinomas anais diagnosticados no Hospital Araújo Jorge, Goiânia/GO, bem como a prevalência do genoma do HPV nesses tumores. Dados clínico-patológicos e sóciodemográficos foram colhidos a partir dos respectivos prontuários e blocos de parafina contendo espécimes de carcinomas anais foram usados para extração de DNA e detecção de HPV, por meio da reação em cadeia da polimerase, usando oligonucleotídeos iniciadores SPF. Quarenta e três casos foram selecionados e tiveram os dados clinico-patológicos analisados, enquanto 38 casos foram testados para a detecção do genoma do HPV. Dentre os pacientes avaliados, 62,8% eram mulheres; 53,4% dos tumores eram carcinomas de células escamosas e 46,5% dos pacientes estavam na faixa etária entre os 60 e 75 anos. Fatores de risco, como tabagismo (39,5% e etilismo (20,9% foram registrados no grupo estudado. Metástases linfonodais foram detectadas em 30,2% dos casos e 7,0% apresentaram metástase à distância. A detecção de HPV foi positiva em 76,0% dos casos analisados e este significativamente associado aos carcinomas de células escamosas. O comportamento agressivo e o estágio avançado dos carcinomas anais descritos no presente estudo destacam a necessidade de medidas de prevenção que contemplem esses tumores, incluindo a vacinação contra o HPV. Keywords: Anal cancer, Characteristics, Human papillomavirus, HPV, HPV16, HPV18, Palavras-chave: Câncer anal, Características, Papilomavirus humano, HPV, HPV16, HPV18

Human papillomavirus-32-associated focal epithelial hyperplasia accompanying HPV-16-positive papilloma-like lesions in oral mucosa.

Science.gov (United States)

Liu, Na; Wang, Jiayi; Lei, Lei; Li, Yanzhong; Zhou, Min; Dan, Hongxia; Zeng, Xin; Chen, Qianming

2013-05-01

Human papillomavirus infection can cause a variety of benign or malignant oral lesions, and the various genotypes can cause distinct types of lesions. To our best knowledge, there has been no report of 2 different human papillomavirus-related oral lesions in different oral sites in the same patient before. This paper reported a patient with 2 different oral lesions which were clinically and histologically in accord with focal epithelial hyperplasia and oral papilloma, respectively. Using DNA extracted from these 2 different lesions, tissue blocks were tested for presence of human papillomavirus followed by specific polymerase chain reaction testing for 6, 11, 13, 16, 18, and 32 subtypes in order to confirm the clinical diagnosis. Finally, human papillomavirus-32-positive focal epithelial hyperplasia accompanying human papillomavirus-16-positive oral papilloma-like lesions were detected in different sites of the oral mucosa. Nucleotide sequence sequencing further confirmed the results. So in our clinical work, if the simultaneous occurrences of different human papillomavirus associated lesions are suspected, the multiple biopsies from different lesions and detection of human papillomavirus genotype are needed to confirm the diagnosis.

Optimization of multimeric human papillomavirus L2 vaccines.

Directory of Open Access Journals (Sweden)

Subhashini Jagu

Full Text Available We sought to define the protective epitopes within the amino terminus of human papillomavirus (HPV type 16 minor capsid protein L2. Passive transfer of mice with rabbit antisera to HPV16 L2 peptides 17-36, 32-51 and 65-81 provided significant protection against vaginal HPV16 challenge, whereas antisera to 47-66, 108-120 or 373-392 did not. Vaccination with L1 virus-like particles induces a high titer, but generally type-restricted neutralizing antibody response. Conversely, vaccination with L2 11-88, especially multimers thereof, induces antibodies that neutralize a broad range of papillomavirus types, albeit at lower titers than for L1 VLP. With the intent of enhancing the immunogenicity and the breadth of protection by focusing the immune response to the key protective epitopes, we designed L2 fusion proteins consisting of residues ∼11-88 of eight divergent mucosal HPV types 6, 16, 18, 31, 39, 51, 56, 73 (11-88×8 or residues ∼13-47 of fifteen HPV types (13-47×15. The 11-88×8 was significantly more immunogenic than 13-47×15 in Balb/c mice regardless of the adjuvant used, suggesting the value of including the 65-81 protective epitope in the vaccine. Since the L2 47-66 peptide antiserum failed to elicit significant protection, we generated an 11-88×8 construct deleted for this region in each subunit (11-88×8Δ. Mice were vaccinated with 11-88×8 and 11-88×8Δ to determine if deletion of this non-protective epitope enhanced the neutralizing antibody response. However, 11-88×8Δ was significantly less immunogenic than 11-88×8, and even the addition of a known T helper epitope, PADRE, to the construct (11-88×8ΔPADRE failed to recover the immunogenicity of 11-88×8 in C57BL/6 mice, suggesting that while L2 47-66 is not a critical protective or T helper epitope, it nevertheless contributes to the immunogenicity of the L2 11-88×8 multimer vaccine.

Study of association and molecular analysis of human papillomavirus in breast cancer of Indian patients: Clinical and prognostic implication.

Directory of Open Access Journals (Sweden)

Saimul Islam

Full Text Available Human papillomavirus (HPV causes tumors primarily Cervical cancer. Recently, inconsistent reports came up in Breast cancer (BC too. In India, despite treatment 70,218 BC patients die each year. So, we explored the association of HPV, if any, with BC prognosis in Indian pre-therapeutic (PT and Neo-adjuvant chemotherapy (NACT patients with subsequent analysis of HPV profile.HPV prevalence was checked and analysis of physical status, copy number, genome variation, promoter methylation and expression (mRNA and protein of the prevalent subtype was done.High prevalence of HPV was observed in both PT (64.0% and NACT (71.0% cases with significant association with younger (20-45 yrs PT patients. Interestingly, HPV infection was significantly increased from adjacent normal breast (9.5%, 2/21, fibro adenomas (30%, 3/10 to tumors (64.8%, 203/313 samples. In both PT and NACT cases, HPV16 was the most prevalent subtype (69.0% followed by HPV18 and HPV33. Survival analysis illustrated hrHPV infected PT patients had worst prognosis. So, detailed analysis of HPV16 profile was done which showed Europian-G350 as the most frequent HPV16 variant along with high rate of integration. Moreover, low copy number and hyper-methylation of P97 early promoter were concordant with low HPV16 E6 and E7 mRNA and protein expression. Notably, four novel variations (KT020838, KT020840, KT020841 and KT020839 in the LCR region and two (KT020836 and KT020837 in the E6 region were identified for the first time along with two novel E6^E7*I (KU199314 and E6^E7*II (KU199315 fusion transcript variants.Thus, significant association of hrHPV with prognosis of Indian BC patients led to additional investigation of HPV16 profile. Outcomes indicated a plausible role of HPV in Indian BC patients.

Viable adenovirus vaccine prototypes: High-level production of a papillomavirus capsid antigen from the major late transcriptional unit

OpenAIRE

Berg, Michael; DiFatta, Julie; Hoiczyk, Egbert; Schlegel, Richard; Ketner, Gary

2005-01-01

Safe, effective, orally delivered, live adenovirus vaccines have been in use for three decades. Recombinant derivatives of the live adenovirus vaccines may prove an economical alternative to current vaccines for a variety of diseases. To explore that possibility, we constructed a series of recombinants that express the major capsid protein (L1) of canine oral papillomavirus (COPV), a model for mucosal human papillomavirus (HPV) infection. Vaccination with virus-like particles (VLPs) composed ...

Prognostic significance of serum antibodies to human papillomavirus-16 E4 and E7 peptides in cervical cancer

NARCIS (Netherlands)

Gaarenstroom, K. N.; Kenter, G. G.; Bonfrer, J. M.; Korse, C. M.; Gallee, M. P.; Hart, A. A.; Müller, M.; Trimbos, J. B.; Helmerhorst, T. J.

1994-01-01

BACKGROUND: The objective of this study was to investigate the prognostic significance of serum antibodies to human papillomavirus (HPV)-16 peptides in patients with squamous cell cervical cancer. METHODS: Pretreatment sera from 78 patients and 198 control women were tested by an enzyme-linked

Understanding the Role of Intrinsic Disorder of Viral Proteins in the Oncogenicity of Different Types of HPV.

Science.gov (United States)

Tamarozzi, Elvira Regina; Giuliatti, Silvana

2018-01-09

Intrinsic disorder is very important in the biological function of several proteins, and is directly linked to their foldability during interaction with their targets. There is a close relationship between the intrinsically disordered proteins and the process of carcinogenesis involving viral pathogens. Among these pathogens, we have highlighted the human papillomavirus (HPV) in this study. HPV is currently among the most common sexually transmitted infections, besides being the cause of several types of cancer. HPVs are divided into two groups, called high- and low-risk, based on their oncogenic potential. The high-risk HPV E6 protein has been the target of much research, in seeking treatments against HPV, due to its direct involvement in the process of cell cycle control. To understand the role of intrinsic disorder of the viral proteins in the oncogenic potential of different HPV types, the structural characteristics of intrinsically disordered regions of high and low-risk HPV E6 proteins were analyzed. In silico analyses of primary sequences, prediction of tertiary structures, and analyses of molecular dynamics allowed the observation of the behavior of such disordered regions in these proteins, thereby proving a direct relationship of structural variation with the degree of oncogenicity of HPVs. The results obtained may contribute to the development of new therapies, targeting the E6 oncoprotein, for the treatment of HPV-associated diseases.

Expression and Purification of Recombinant Proteins in Escherichia coli with a His6 or Dual His6-MBP Tag.

Science.gov (United States)

Raran-Kurussi, Sreejith; Waugh, David S

2017-01-01

Rapid advances in bioengineering and biotechnology over the past three decades have greatly facilitated the production of recombinant proteins in Escherichia coli. Affinity-based methods that employ protein or peptide based tags for protein purification have been instrumental in this progress. Yet insolubility of recombinant proteins in E. coli remains a persistent problem. One way around this problem is to fuse an aggregation-prone protein to a highly soluble partner. E. coli maltose-binding protein (MBP) is widely acknowledged as a highly effective solubilizing agent. In this chapter, we describe how to construct either a His 6 - or a dual His 6 -MBP tagged fusion protein by Gateway ® recombinational cloning and how to evaluate their yield and solubility. We also describe a simple and rapid procedure to test the solubility of proteins after removing their N-terminal fusion tags by tobacco etch virus (TEV) protease digestion. The choice of whether to use a His 6 tag or a His 6 -MBP tag can be made on the basis of this solubility test.

Bovine papillomavirus type 2 (BPV-2) E5 oncoprotein binds to the subunit D of the V₁-ATPase proton pump in naturally occurring urothelial tumors of the urinary bladder of cattle.

Science.gov (United States)

Roperto, Sante; Russo, Valeria; Borzacchiello, Giuseppe; Urraro, Chiara; Lucà, Roberta; Esposito, Iolanda; Riccardi, Marita Georgia; Raso, Cinzia; Gaspari, Marco; Ceccarelli, Dora Maria; Galasso, Rocco; Roperto, Franco

2014-01-01

Active infection by bovine papillomavirus type 2 (BPV-2) was documented for fifteen urinary bladder tumors in cattle. Two were diagnosed as papillary urothelial neoplasm of low malignant potential (PUNLMP), nine as papillary and four as invasive urothelial cancers. In all cancer samples, PCR analysis revealed a BPV-2-specific 503 bp DNA fragment. E5 protein, the major oncoprotein of the virus, was shown both by immunoprecipitation and immunohistochemical analysis. E5 was found to bind to the activated (phosphorylated) form of the platelet derived growth factor β receptor. PDGFβR immunoprecipitation from bladder tumor samples and from normal bladder tissue used as control revealed a protein band which was present in the pull-down from bladder cancer samples only. The protein was identified with mass spectrometry as "V₁-ATPase subunit D", a component of the central stalk of the V₁-ATPase vacuolar pump. The subunit D was confirmed in this complex by coimmunoprecipitation investigations and it was found to colocalize with the receptor. The subunit D was also shown to be overexpressed by Western blot, RT-PCR and immunofluorescence analyses. Immunoprecipitation and immunofluorescence also revealed that E5 oncoprotein was bound to the subunit D. For the first time, a tri-component complex composed of E5/PDGFβR/subunit D has been documented in vivo. Previous in vitro studies have shown that the BPV-2 E5 oncoprotein binds to the proteolipid c ring of the V₀-ATPase sector. We suggest that the E5/PDGFβR/subunit D complex may perturb proteostasis, organelle and cytosol homeostasis, which can result in altered protein degradation and in autophagic responses.

Papillomaviruses: a systematic review

Directory of Open Access Journals (Sweden)

Rodrigo Pinheiro Araldi

Full Text Available Abstract In the last decades, a group of viruses has received great attention due to its relationship with cancer development and its wide distribution throughout the vertebrates: the papillomaviruses. In this article, we aim to review some of the most relevant reports concerning the use of bovines as an experimental model for studies related to papillomaviruses. Moreover, the obtained data contributes to the development of strategies against the clinical consequences of bovine papillomaviruses (BPV that have led to drastic hazards to the herds. To overcome the problem, the vaccines that we have been developing involve recombinant DNA technology, aiming at prophylactic and therapeutic procedures. It is important to point out that these strategies can be used as models for innovative procedures against HPV, as this virus is the main causal agent of cervical cancer, the second most fatal cancer in women.

Hidden Structural Codes in Protein Intrinsic Disorder.

Science.gov (United States)

Borkosky, Silvia S; Camporeale, Gabriela; Chemes, Lucía B; Risso, Marikena; Noval, María Gabriela; Sánchez, Ignacio E; Alonso, Leonardo G; de Prat Gay, Gonzalo

2017-10-17

Intrinsic disorder is a major structural category in biology, accounting for more than 30% of coding regions across the domains of life, yet consists of conformational ensembles in equilibrium, a major challenge in protein chemistry. Anciently evolved papillomavirus genomes constitute an unparalleled case for sequence to structure-function correlation in cases in which there are no folded structures. E7, the major transforming oncoprotein of human papillomaviruses, is a paradigmatic example among the intrinsically disordered proteins. Analysis of a large number of sequences of the same viral protein allowed for the identification of a handful of residues with absolute conservation, scattered along the sequence of its N-terminal intrinsically disordered domain, which intriguingly are mostly leucine residues. Mutation of these led to a pronounced increase in both α-helix and β-sheet structural content, reflected by drastic effects on equilibrium propensities and oligomerization kinetics, and uncovers the existence of local structural elements that oppose canonical folding. These folding relays suggest the existence of yet undefined hidden structural codes behind intrinsic disorder in this model protein. Thus, evolution pinpoints conformational hot spots that could have not been identified by direct experimental methods for analyzing or perturbing the equilibrium of an intrinsically disordered protein ensemble.

Human papillomavirus and tar hypothesis for squamous cell cervical ...

Indian Academy of Sciences (India)

2010-08-09

Aug 9, 2010 ... Keywords. Cervical cancer; co-factors; human papillomavirus; tar-based vaginal douche; tobacco smoke; wood smoke. Author Affiliations. Christina Bennett1 Allen E Kuhn2 Harry W Haverkos3. Indiana University School of Medicine, Indianapolis, Indiana 46202-5149, USA; Suite 300, Hamilton Mason Road ...

Seroprevalence of Human Papillomavirus Types 6, 11, 16 and 18 in Chinese Women

Directory of Open Access Journals (Sweden)

Ji Jia

2012-06-01

Full Text Available Abstract Background Human papillomavirus (HPV seroprevalence data have not previously been reported for different geographical regions of China. This study investigated the cross-sectional seroprevalence of antibodies to HPV 6, 11, 16, and 18 virus-like particles in Chinese women. Methods Population-based samples of women were enrolled from 2006 to 2007 in 3 rural and 2 urban areas of China. Each consenting woman completed a questionnaire and provided a blood sample. Serum antibodies were detected using a competitive Luminex immunoassay that measures antibodies to type-specific, neutralizing epitopes on the virus-like particles. Results A total of 4,731 women (median age 35, age range 14-54 were included, of which 4,211 were sexually active women (median age 37 and 520 virgins (median age 18. Low risk HPV 6 was the most common serotype detected (7.3%, followed by HPV 16 (5.6%, HPV 11 (2.9%, and HPV 18 (1.9%. Overall HPV seroprevalence to any type was significantly higher among sexually active women (15.8% than virgins (2.5% (P = 0.005. Overall seroprevalence among sexually active women gradually increased with age. Women from rural regions had significantly lower overall seroprevalence (Odds Ratio (OR = 0.7; 95% CI: 0.6-0.9, versus metropolitan regions, P  = 4 partners versus 1 partner, P  Conclusions HPV seroprevalence differed significantly by age, geography, and sexual behavior within China, which all should be considered when implementing an optimal prophylactic HPV vaccination program in China.

Attenuated Recombinant Influenza A Virus Expressing HPV16 E6 and E7 as a Novel Therapeutic Vaccine Approach.

Directory of Open Access Journals (Sweden)

Christoph Jindra

Full Text Available Persistent infection with high-risk human papillomavirus (HPV types, most often HPV16 and HPV18, causes all cervical and most anal cancers, and a subset of vulvar, vaginal, penile and oropharyngeal carcinomas. Two prophylactic virus-like particle (VLPs-based vaccines, are available that protect against vaccine type-associated persistent infection and associated disease, yet have no therapeutic effect on existing lesions or infections. We have generated recombinant live-attenuated influenza A viruses expressing the HPV16 oncogenes E6 and E7 as experimental immunotherapeutic vaccine candidates. The influenza A virus life cycle lacks DNA intermediates as important safety feature. Different serotypes were generated to ensure efficient prime and boost immunizations. The immune response to vaccination in C57BL/6 mice was characterized by peptide ELISA and IFN-γ ELISpot, demonstrating induction of cell-mediated immunity to HPV16 E6 and E7 oncoproteins. Prophylactic and therapeutic vaccine efficacy was analyzed in the murine HPV16-positive TC-1 tumor challenge model. Subcutaneous (s.c. prime and boost vaccinations of mice with recombinant influenza A serotypes H1N1 and H3N2, followed by challenge with TC-1 cells resulted in complete protection or significantly reduced tumor growth as compared to control animals. In a therapeutic setting, s.c. vaccination of mice with established TC-1 tumors decelerated tumor growth and significantly prolonged survival. Importantly, intralesional vaccine administration induced complete tumor regression in 25% of animals, and significantly reduced tumor growth in 50% of mice. These results suggest recombinant E6E7 influenza viruses as a promising new approach for the development of a therapeutic vaccine against HPV-induced disease.

Human Papillomavirus Antibodies and Future Risk of Anogenital Cancer : A Nested Case-Control Study in the European Prospective Investigation Into Cancer and Nutrition Study

NARCIS (Netherlands)

Kreimer, Aimee R.; Brennan, Paul; Kuhs, Krystle A. Lang; Waterboer, Tim; Clifford, Gary; Franceschi, Silvia; Michel, Angelika; Willhauck-Fleckenstein, Martina; Riboli, Elio; Castellsague, Xavier; Hildesheim, Allan; Fortner, Renee Turzanski; Kaaks, Rudolf; Palli, Domenico; Ljuslinder, Ingrid; Panico, Salvatore; Clavel-Chapelon, Francoise; Boutron-Ruault, Marie-Christine; Mesrine, Sylvie; Trichopoulou, Antonia; Lagiou, Pagona; Trichopoulos, Dimitrios; Peeters, Petra H.; Cross, Amanda J.; Bueno-de-Mesquita, H. Bas; Vineis, Paolo; Larranaga, Nerea; Pala, Valeria; Sanchez, Maria-Jose; Navarro, Carmen; Barricarte, Aurelio; Tumino, Rosario; Khaw, Kay-Tee; Wareham, Nicholas; Boeing, Heiner; Steffen, Annika; Travis, Ruth C.; Ramon Quiros, J.; Weiderpass, Elisabete; Pawlita, Michael; Johansson, Mattias

2015-01-01

Purpose Human papillomavirus (HPV) type 16 (HPV16) causes cancer at several anatomic sites. In the European Prospective Investigation Into Cancer and Nutrition study, HPV16 E6 seropositivity was present more than 10 years before oropharyngeal cancer diagnosis and was nearly absent in controls. The

Incidence of cervical human papillomavirus infection in systemic lupus erythematosus women.

Science.gov (United States)

Mendoza-Pinto, C; García-Carrasco, M; Vallejo-Ruiz, V; Méndez-Martínez, S; Taboada-Cole, A; Etchegaray-Morales, I; Muñóz-Guarneros, M; Reyes-Leyva, J; López-Colombo, A

2017-08-01

Objectives Our objective was to study the incidence, persistence and clearance of human papillomavirus infection in systemic lupus erythematosus women and assess risk factors for persistence of human papillomavirus infection. Methods We carried out a prospective, observational cohort study of 127 systemic lupus erythematosus women. Patients were evaluated at baseline and at three years. Traditional and systemic lupus erythematosus women-related disease risk factors were collected. Gynaecological evaluations and cervical cytology screening were made. Human papillomavirus detection and genotyping were made by polymerase chain reaction and linear array. Results The cumulative prevalence of human papillomavirus infection increased from 22.8% at baseline to 33.8% at three years; p = lupus erythematosus women, the cumulative prevalence of human papillomavirus infection, including high risk-human papillomavirus and multiple human papillomavirus infections, may increase over time. Most persistent infections were low risk-human papillomavirus. The number of lifetime sexual partners and the cumulative cyclophosphamide dose were independently associated with incident human papillomavirus infection.

Subcellular Trafficking of the Papillomavirus Genome during Initial Infection: The Remarkable Abilities of Minor Capsid Protein L2

Directory of Open Access Journals (Sweden)

Samuel K. Campos

2017-12-01

Full Text Available Since 2012, our understanding of human papillomavirus (HPV subcellular trafficking has undergone a drastic paradigm shift. Work from multiple laboratories has revealed that HPV has evolved a unique means to deliver its viral genome (vDNA to the cell nucleus, relying on myriad host cell proteins and processes. The major breakthrough finding from these recent endeavors has been the realization of L2-dependent utilization of cellular sorting factors for the retrograde transport of vDNA away from degradative endo/lysosomal compartments to the Golgi, prior to mitosis-dependent nuclear accumulation of L2/vDNA. An overview of current models of HPV entry, subcellular trafficking, and the role of L2 during initial infection is provided below, highlighting unresolved questions and gaps in knowledge.

Detection and analysis of human papillomavirus 16 and 18 homologous DNA sequences in oral lesions.

Science.gov (United States)

Wen, S; Tsuji, T; Li, X; Mizugaki, Y; Hayatsu, Y; Shinozaki, F

1997-01-01

The prevalence of human papillomavirus (HPV) 16 and 18 was investigated in oral lesions of the population of northeast China including squamous cell carcinomas (SCCs), candida leukoplakias, lichen planuses and papillomas, by southern blot hybridization with polymerase chain reaction (PCR). Amplified HPV16 and 18 E6 DNA was analyzed by cycle sequence. HPV DNA was detected in 14 of 45 SCCs (31.1%). HPV18 E6 DNA and HPV16 E6. DNA were detected in 24.4% and 20.0% of SCCs. respectively. Dual infection of both HPV 16 and HPV 18 was detected in 6 of 45 SCCs (13.3%), but not in other oral lesions. HPV 18 E6 DNA was also detected in 2 of 3 oral candida leukoplakias, but in none of the 5 papillomas. Our study indicated that HPV 18 infection might be more frequent than HPV 16 infection in oral SCCs in northeast Chinese, dual infection of high risk HPV types was restricted in oral SCCs, and that HPV infection might be involved in the pathogenesis of oral candida leukoplakia.

Impact of viral E2-gene status on outcome after radiotherapy for patients with human papillomavirus 16-positive cancer of the uterine cervix

International Nuclear Information System (INIS)

Lindel, Katja; Villiers, Ethel-Michele de; Burri, Philipp; Studer, Ueli; Altermatt, Hans J.; Greiner, Richard H.; Gruber, Guenther

2006-01-01

Purpose: Integration of high-risk papillomavirus DNA has been considered an important step in oncogenic progression to cervical carcinoma. Disruption of the human papillomavirus (HPV) genome within the E2 gene is frequently a consequence. This study investigated the influence of episomal viral DNA on outcome in patients with advanced cervical cancer treated with primary radiotherapy. Methods and Materials: Paraffin-embedded biopsies of 82 women with locally advanced cervical cancer could be analyzed for HPV infection by multiplex polymerase chain reaction (PCR) by use of SPF1/2 primers. E2-gene intactness of HPV-16-positive samples was analyzed in 3 separate amplification reactions by use of the E2A, E2B, E2C primers. Statistical analyses (Kaplan-Meier method; log-rank test) were performed for overall survival (OS), disease-free survival (DFS), local progression-free survival (LPFS), and distant metastases-free survival (DMFS). Results: Sixty-one (75%) of 82 carcinomas were HPV positive, 44 of them for HPV-16 (72%). Seventeen of the 44 HPV-16-positive tumors (39%) had an intact E2 gene. Patients with a HPV-16-positive tumor and an intact E2 gene showed a trend for a better DFS (58% vs. 38%, p = 0.06) compared with those with a disrupted E2 gene. A nonsignificant difference occurred regarding OS (87% vs. 66%, p = 0.16) and DMFS (57% vs. 48%, p = 0.15). Conclusion: E2-gene status may be a promising new target, but more studies are required to elucidate the effect of the viral E2 gene on outcome after radiotherapy in HPV-positive tumors

The fanconi anemia pathway limits human papillomavirus replication.

Science.gov (United States)

Hoskins, Elizabeth E; Morreale, Richard J; Werner, Stephen P; Higginbotham, Jennifer M; Laimins, Laimonis A; Lambert, Paul F; Brown, Darron R; Gillison, Maura L; Nuovo, Gerard J; Witte, David P; Kim, Mi-Ok; Davies, Stella M; Mehta, Parinda A; Butsch Kovacic, Melinda; Wikenheiser-Brokamp, Kathryn A; Wells, Susanne I

2012-08-01

High-risk human papillomaviruses (HPVs) deregulate epidermal differentiation and cause anogenital and head and neck squamous cell carcinomas (SCCs). The E7 gene is considered the predominant viral oncogene and drives proliferation and genome instability. While the implementation of routine screens has greatly reduced the incidence of cervical cancers which are almost exclusively HPV positive, the proportion of HPV-positive head and neck SCCs is on the rise. High levels of HPV oncogene expression and genome load are linked to disease progression, but genetic risk factors that regulate oncogene abundance and/or genome amplification remain poorly understood. Fanconi anemia (FA) is a genome instability syndrome characterized at least in part by extreme susceptibility to SCCs. FA results from mutations in one of 15 genes in the FA pathway, whose protein products assemble in the nucleus and play important roles in DNA damage repair. We report here that loss of FA pathway components FANCA and FANCD2 stimulates E7 protein accumulation in human keratinocytes and causes increased epithelial proliferation and basal cell layer expansion in the HPV-positive epidermis. Additionally, FANCD2 loss stimulates HPV genome amplification in differentiating cells, demonstrating that the intact FA pathway functions to restrict the HPV life cycle. These findings raise the possibility that FA genes suppress HPV infection and disease and suggest possible mechanism(s) for reported associations of HPV with an FA cohort in Brazil and for allelic variation of FA genes with HPV persistence in the general population.

Heterologous production of human papillomavirus type-16 L1 protein by a lactic acid bacterium

Directory of Open Access Journals (Sweden)

Bermúdez-Humarán Luis G

2009-08-01

Full Text Available Abstract Background The expression of vaccine antigens in lactic acid bacteria (LAB is a safe and cost-effective alternative to traditional expression systems. In this study, we investigated i the expression of Human papillomavirus type 16 (HPV-16 L1 major capsid protein in the model LAB Lactococcus lactis and ii the ability of the resulting recombinant strain to produce either capsomer-or virus-like particles (VLPs. Results and conclusion HPV-16 L1 gene was cloned into two vectors, pCYT and pSEC, designed for controlled intra- or extracellular heterologous expression in L. lactis, respectively. The capacity of L. lactis harboring either pCYT:L1 or pSEC:L1 plasmid to accumulate L1 in the cytoplasm and supernatant samples was confirmed by Western blot assays. Electron microscopy analysis suggests that, L1 protein produced by recombinant lactococci can self-assemble into structures morphologically similar to VLPs intracellularly. The presence of conformational epitopes on the L. lactis-derived VLPs was confirmed by ELISA using an anti-HPV16 L1 capsid antigen antibody. Our results support the feasibility of using recombinant food-grade LAB, such as L. lactis, for the production of L1-based VLPs and open the possibility for the development of a new safe mucosal vector for HPV-16 prophylactic vaccination.

Establishment of a Wheat Cell-Free Synthesized Protein Array Containing 250 Human and Mouse E3 Ubiquitin Ligases to Identify Novel Interaction between E3 Ligases and Substrate Proteins.

Directory of Open Access Journals (Sweden)

Hirotaka Takahashi

Full Text Available Ubiquitination is a key post-translational modification in the regulation of numerous biological processes in eukaryotes. The primary roles of ubiquitination are thought to be the triggering of protein degradation and the regulation of signal transduction. During protein ubiquitination, substrate specificity is mainly determined by E3 ubiquitin ligase (E3. Although more than 600 genes in the human genome encode E3, the E3s of many target proteins remain unidentified owing to E3 diversity and the instability of ubiquitinated proteins in cell. We demonstrate herein a novel biochemical analysis for the identification of E3s targeting specific proteins. Using wheat cell-free protein synthesis system, a protein array containing 227 human and 23 mouse recombinant E3s was synthesized. To establish the high-throughput binding assay using AlphaScreen technology, we selected MDM2 and p53 as the model combination of E3 and its target protein. The AlphaScreen assay specifically detected the binding of p53 and MDM2 in a crude translation mixture. Then, a comprehensive binding assay using the E3 protein array was performed. Eleven of the E3s showed high binding activity, including four previously reported E3s (e.g., MDM2, MDM4, and WWP1 targeting p53. This result demonstrated the reliability of the assay. Another interactors, RNF6 and DZIP3-which there have been no report to bind p53-were found to ubiquitinate p53 in vitro. Further analysis showed that RNF6 decreased the amount of p53 in H1299 cells in E3 activity-dependent manner. These results suggest the possibility that the RNF6 ubiquitinates and degrades p53 in cells. The novel in vitro screening system established herein is a powerful tool for finding novel E3s of a target protein.

Clinical performance of a human papillomavirus messenger RNA test (Aptima HPV Assay) on residual material from archived 3-year-old PreservCyt samples with low-grade squamous intraepithelial lesion

DEFF Research Database (Denmark)

Waldstrøm, Marianne; Ornskov, Dorthe

2011-01-01

Human papillomavirus (HPV) testing is widely used in the triage of women with a borderline smear result but the efficiency of testing women with low-grade squamous intraepithelial lesion (LSIL) is less clear, mainly because of lack of specificity. New HPV tests are emerging, which detect E6/E7...

E2F-6: a novel member of the E2F family is an inhibitor of E2F-dependent transcription

DEFF Research Database (Denmark)

Cartwright, P; Müller, H; Wagener, C

1998-01-01

with E2Fs 1-5, especially within the DNA binding, heterodimerization and marked box domains. Unlike E2Fs 1-5, E2F-6 lacks a transactivation and a pocket protein binding domain, hence, forms a unique third group within the E2F family. E2F-6 is a nuclear protein that can form heterodimers with the DP......The E2F family of transcription factors are essential for the regulation of genes required for appropriate progression through the cell cycle. Five members of the E2F family have been previously reported, namely E2F1-5. All five are key elements in transcriptional regulation of essential genes......, and they can be divided into two functional groups, those that induce S-phase progression when overexpressed in quiescent cells (E2Fs 1-3), and those that do not (E2Fs 4-5). Here, we describe the identification of a novel member of this family, which we refer to as E2F-6. E2F-6 shares significant homology...

Human papillomavirus 33 worldwide genetic variation and associated risk of cervical cancer

Science.gov (United States)

Chen, Alyce A.; Heideman, Daniëlle A.M.; Boon, Debby; Chen, Zigui; Burk, Robert D.; De Vuyst, Hugo; Gheit, Tarik; Snijders, Peter J.F.; Tommasino, Massimo; Franceschi, Silvia; Clifford, Gary M.

2014-01-01

Human papillomavirus (HPV) 33, a member of the HPV16-related alpha-9 species group, is found in approximately 5% of cervical cancers worldwide. The current study aimed to characterize the genetic diversity of HPV33 and to explore the association of HPV33 variants with the risk for cervical cancer. Taking advantage of the International Agency for Research on Cancer biobank, we sequenced the entire E6 and E7 open reading frames of 213 HPV33-positive cervical samples from 30 countries. We identified 28 HPV33 variants that formed 5 phylogenetic groups: the previously identified A1, A2, and B (sub) lineages and the novel A3 and C (sub)lineages. The A1 sublineage was strongly over-represented in cervical cases compared to controls in both Africa and Europe. In conclusion, we provide a classification system for HPV33 variants based on the sequence of E6 and E7 and suggest that the association of HPV33 with cervical cancer may differ by variant (sub)lineage. PMID:24314666

Human papillomavirus infection in Beijing, People's Republic of China: a population-based study

Science.gov (United States)

Zhao, R; Zhang, W Y; Wu, M H; Zhang, S W; Pan, J; Zhu, L; Zhang, Y P; Li, H; Gu, Y S; Liu, X Z

2009-01-01

Background: No recent data exist on human papillomavirus (HPV) infection in Beijing, People's Republic of China. Materials and method We interviewed and examined a representative, randomly selected sample of 5552 sexually active women aged 25–54 years. Cervical cell samples were analysed for HPV DNA by a MY09/11-based PCR assay. Results: Human papillomavirus prevalence was 6.7% overall and 4.8% among women without cervical abnormalities. Of the 21 subtypes identified, HPV16 was the commonest type (2.6% overall; 39.1% of HPV-positive women), followed by HPV 58 (1.0%), 33 (0.8%), 43 (0.7%) and 56 (0.7%). High-risk HPV types predominated in all age groups. Human papillomavirus prevalence was highest in young to middle-aged women. Marital status, number of husband's sexual partners, age at sexual debut and nulligravidity were all associated with being HPV positive. Conclusions: In our survey, HPV 16, HPV 58 and HPV 33 were the most prevalent HPV types in Beijing, indicating the potential for the prophylactic HPV 16/18 vaccine in China. PMID:19862002

Transient expression of Human papillomavirus type 16 L2 epitope fused to N- and C-terminus of coat protein of Potato virus X in plants

Czech Academy of Sciences Publication Activity Database

Čeřovská, Noemi; Hoffmeisterová, Hana; Moravec, Tomáš; Plchová, Helena; Folwarczna, Jitka; Synková, Helena; Ryšlavá, H.; Ludvíková, V.; Šmahel, M.

2012-01-01

Roč. 37, č. 1 (2012), s. 125-133 ISSN 0250-5991 R&D Projects: GA ČR GA521/06/0973; GA ČR GA521/09/1525 Institutional research plan: CEZ:AV0Z50380511 Keywords : Human papillomavirus (HPV-16) * L2-and E7-derived epitopes * transient expression Subject RIV: FD - Oncology ; Hematology Impact factor: 1.759, year: 2012

Overexpressed Proteins in Hypervirulent Clade 8 and Clade 6 Strains of Escherichia coli O157:H7 Compared to E. coli O157:H7 EDL933 Clade 3 Strain.

Directory of Open Access Journals (Sweden)

Natalia Amigo

Full Text Available Escherichia coli O157:H7 is responsible for severe diarrhea and hemolytic uremic syndrome (HUS, and predominantly affects children under 5 years. The major virulence traits are Shiga toxins, necessary to develop HUS and the Type III Secretion System (T3SS through which bacteria translocate effector proteins directly into the host cell. By SNPs typing, E. coli O157:H7 was separated into nine different clades. Clade 8 and clade 6 strains were more frequently associated with severe disease and HUS. In this study, we aimed to identify differentially expressed proteins in two strains of E. coli O157:H7 (clade 8 and clade 6, obtained from cattle and compared them with the well characterized reference EDL933 strain (clade 3. Clade 8 and clade 6 strains show enhanced pathogenicity in a mouse model and virulence-related properties. Proteins were extracted and analyzed using the TMT-6plex labeling strategy associated with two dimensional liquid chromatography and mass spectrometry in tandem. We detected 2241 proteins in the cell extract and 1787 proteins in the culture supernatants. Attention was focused on the proteins related to virulence, overexpressed in clade 6 and 8 strains compared to EDL933 strain. The proteins relevant overexpressed in clade 8 strain were the curli protein CsgC, a transcriptional activator (PchE, phage proteins, Stx2, FlgM and FlgD, a dienelactone hydrolase, CheW and CheY, and the SPATE protease EspP. For clade 6 strain, a high overexpression of phage proteins was detected, mostly from Stx2 encoding phage, including Stx2, flagellin and the protease TagA, EDL933_p0016, dienelactone hydrolase, and Haemolysin A, amongst others with unknown function. Some of these proteins were analyzed by RT-qPCR to corroborate the proteomic data. Clade 6 and clade 8 strains showed enhanced transcription of 10 out of 12 genes compared to EDL933. These results may provide new insights in E. coli O157:H7 mechanisms of pathogenesis.

Role of Ultraviolet Radiation in Papillomavirus-Induced Disease

Science.gov (United States)

Uberoi, Aayushi; Yoshida, Satoshi; Frazer, Ian H.; Pitot, Henry C.; Lambert, Paul F.

2016-01-01

Human papillomaviruses are causally associated with 5% of human cancers. The recent discovery of a papillomavirus (MmuPV1) that infects laboratory mice provides unique opportunities to study the life cycle and pathogenesis of papillomaviruses in the context of a genetically manipulatable host organism. To date, MmuPV1-induced disease has been found largely to be restricted to severely immunodeficient strains of mice. In this study, we report that ultraviolet radiation (UVR), specifically UVB spectra, causes wild-type strains of mice to become highly susceptible to MmuPV1-induced disease. MmuPV1-infected mice treated with UVB develop warts that progress to squamous cell carcinoma. Our studies further indicate that UVB induces systemic immunosuppression in mice that correlates with susceptibility to MmuPV1-associated disease. These findings provide new insight into how MmuPV1 can be used to study the life cycle of papillomaviruses and their role in carcinogenesis, the role of host immunity in controlling papillomavirus-associated pathogenesis, and a basis for understanding in part the role of UVR in promoting HPV infection in humans. PMID:27244228

Impact of 6-month frozen storage of cervical specimens in alkaline buffer conditions on human papillomavirus genotyping.

Science.gov (United States)

LaMere, Brandon J; Howell, Renee; Fetterman, Barbara; Shieh, Jen; Castle, Philip E

2008-08-01

The impact of 6-month storage of cervical specimens under alkaline conditions that occurs as the result of Hybrid Capture 2 testing on human papillomavirus (HPV) genotyping is not well documented. To examine this issue, 143 frozen hc2-positive specimens in specimen transport medium were selected at random from each of the following groups: specimens stored for 6 months, 4 months, and 2.5 months under alkaline pH (pH 12-13) and specimens stored 1 month at neutral pH (pH 6-7) as controls. Specimens were tested in a masked fashion for 20 HPV genotypes (HPV6, 11, 16, 18, 26, 31, 33, 35, 39, 45, 51, 52, 53, 56, 58, 59, 66, 68, 73, and 82) using a prototype, research-use-only GP5+/6+ L1 consensus PCR method and multiplex hybridization using Luminex xMAP for detection of specific HPV genotypes One control specimen had missing test results. There were no statistical differences in the number of HPV genotypes detected, number of carcinogenic HPV genotypes detected, or in the signal strength among HPV-positive results across groups. Six-month frozen storage of cervical specimens at alkaline pH had little impact on testing for HPV genotypes among hc2-positive women using this HPV genotyping method.

Etiological role of human papillomavirus infection for inverted papilloma of the bladder.

Science.gov (United States)

Shigehara, Kazuyoshi; Sasagawa, Toshiyuki; Doorbar, John; Kawaguchi, Shohei; Kobori, Yoshitomo; Nakashima, Takao; Shimamura, Masayoshi; Maeda, Yuji; Miyagi, Tohru; Kitagawa, Yasuhide; Kadono, Yoshifumi; Konaka, Hiroyuki; Mizokami, Atsushi; Koh, Eitetsu; Namiki, Mikio

2011-02-01

The status of human papillomavirus (HPV) infection in urothelial inverted papilloma was examined in the present study. Formalin-fixed and paraffin-embedded tissues from eight cases of inverted papilloma of the bladder were studied. The presence of HPV-DNA was examined by modified GP5/6+PCR using archival tissue sections by microdissection. HPV genotype was determined with a Hybri-Max HPV genotyping kit. Immunohistochemical analysis for p16-INK4a, mcm7, HPV-E4, and L1, and in situ hybridization for the HPV genome were performed. HPV was detected in seven of eight cases (87.5%) of inverted papilloma. Three cases were diagnosed as inverted papilloma with atypia, while the remaining five were typical cases. HPV-18 was detected in two cases, including one inverted papilloma with atypia, and HPV-16 was detected in four cases, including one inverted papilloma with atypia. Multiple HPV type infection was detected in one typical case and one atypical case. High-risk HPV was present in all HPV-positive cases. Cellular proteins, p16-INK4a and mcm7, which are surrogate markers for HPV-E7 expression, were detected in all HPV-positive cases, and their levels were higher in inverted papilloma with atypia than in typical cases. In contrast, HPV-E4 and L1, which are markers for HPV propagation, were observed in some parts of the typical inverted papilloma tissue. High-risk HPV infection may be one of the causes of urothelial inverted papilloma, and inverted papilloma with atypia may have malignant potential. 2010 Wiley-Liss, Inc.

Is Human Papillomavirus Associated with Prostate Cancer Survival?

Directory of Open Access Journals (Sweden)

Mariarosa Pascale

2013-01-01

Full Text Available The role of human papillomavirus (HPV in prostate carcinogenesis is highly controversial: some studies suggest a positive association between HPV infection and an increased risk of prostate cancer (PCa, whereas others do not reveal any correlation. In this study, we investigated the prognostic impact of HPV infection on survival in 150 primary PCa patients. One hundred twelve (74.67% patients had positive expression of HPV E7 protein, which was evaluated in tumour tissue by immunohistochemistry. DNA analysis on a subset of cases confirmed HPV infection and revealed the presence of genotype 16. In Kaplan-Meier analysis, HPV-positive cancer patients showed worse overall survival (OS (median 4.59 years compared to HPV-negative (median 8.24 years, P=0.0381. In multivariate analysis age (P<0.001, Gleason score (P<0.001, nuclear grading (P=0.002, and HPV status (P=0.034 were independent prognostic factors for OS. In our cohort, we observed high prevalence of HPV nuclear E7 oncoprotein and an association between HPV infection and PCa survival. In the debate about the oncogenic activity of HPV in PCa, our results further confirm the need for additional studies to clarify the possible role of HPV in prostate carcinogenesis.

Disruption of HPV16-E7 by CRISPR/Cas System Induces Apoptosis and Growth Inhibition in HPV16 Positive Human Cervical Cancer Cells

Directory of Open Access Journals (Sweden)

Zheng Hu

2014-01-01

Full Text Available High-risk human papillomavirus (HR-HPV has been recognized as a major causative agent for cervical cancer. Upon HPV infection, early genes E6 and E7 play important roles in maintaining malignant phenotype of cervical cancer cells. By using clustered regularly interspaced short palindromic repeats- (CRISPR- associated protein system (CRISPR/Cas system, a widely used genome editing tool in many organisms, to target HPV16-E7 DNA in HPV positive cell lines, we showed for the first time that the HPV16-E7 single-guide RNA (sgRNA guided CRISPR/Cas system could disrupt HPV16-E7 DNA at specific sites, inducing apoptosis and growth inhibition in HPV positive SiHa and Caski cells, but not in HPV negative C33A and HEK293 cells. Moreover, disruption of E7 DNA directly leads to downregulation of E7 protein and upregulation of tumor suppressor protein pRb. Therefore, our results suggest that HPV16-E7 gRNA guided CRISPR/Cas system might be used as a therapeutic strategy for the treatment of cervical cancer.

Positive and negative regulation of cell proliferation by E2F-1: influence of protein level and human papillomavirus oncoproteins

DEFF Research Database (Denmark)

Melillo, R M; Helin, K; Lowy, D R

1994-01-01

E2F-1 is a member of a family of transcription factors implicated in the activation of genes required for the progression through the S phase of the cell cycle. We have examined the biological activities of E2F-1 with short-term colony-forming assays and long-term immortalization assays. High...... to immortalize NHFKs, or by a transdominant p53 mutant. High levels of E2F-1 also inhibited growth of primary and established fibroblasts. The growth-inhibitory activity required the DNA binding function of E2F-1 but not its transactivation or pRB binding activities. A positive role for lower levels of E2F-1...... in NHFK immortalization was established by examining the ability of E2F-1 to complement HPV16 E7 mutants that were unable to cooperate with HPV16 E6 to immortalize NHFKs. Although E2F-1 was unable by itself to cooperate with E6, it did, in conjunction with E6, complement a p24GLY mutant of E7...

Heterodimerization of the transcription factors E2F-1 and DP-1 is required for binding to the adenovirus E4 (ORF6/7) protein

DEFF Research Database (Denmark)

Helin, K; Harlow, E

1994-01-01

Adenovirus infection leads to E1A-dependent activation of the transcription factor E2F. E2F has recently been identified in complexes with cellular proteins such as the retinoblastoma protein (pRB) and the two pRB family members p107 and p130. E1A dissociates E2F from these cellular proteins...

HUMAN PAPILLOMA VIRUS IMMUNOGEN CREATION ON THE BASE OF CHIMERIC RECOMBINANT PROTEIN L2E7

Directory of Open Access Journals (Sweden)

I. S. Malakhov

2016-01-01

infection value of stated vaccines. According to information from literature, N-terminus of the L2 protein can induce non strain-specific neutralizing antibody that protects organism from papillomavirus challenge. E7 protein is a virus oncogene, its function is unlimited proliferation of infected cells that cause malignization in chronic course of disease. This protein is a very attractive target for therapeutic vaccines because of its necessity both for virus life cycle and sustenance of malignant phenotype in cancer cells. So, in this research the design of immunogen on the base of proteins HPV L2 and E7 is selected, vaccine on the base of which will avoid the disadvantages of Gardasil and Cervarix listed above. The stain-producer of protein on the base of cells E. coli was created. The protein was purified in denaturing reducing conditions by metal-affine chromatography and refold by sequential remove of urea and 2-mercaptoethanol.

Frequent detection of human papillomavirus 16 E2-specific T-helper immunity in healthy subjects

NARCIS (Netherlands)

de Jong, Annemieke; van der Burg, Sjoerd H.; Kwappenberg, Kitty M. C.; van der Hulst, Jeanette M.; Franken, Kees L. M. C.; Geluk, Annemieke; van Meijgaarden, Krista E.; Drijfhout, Jan Wouter; Kenter, Gemma; Vermeij, Pieter; Melief, Cornelis J. M.; Offringa, Rienk

2002-01-01

The incidence of genital human papillomavirus (HPV) infections is high in young, sexually active individuals. Most infections are cleared within 1 year after infection. The targets for the cellular immune response in this process of viral clearance remain to be identified, but the expression pattern

Role of Ultraviolet Radiation in Papillomavirus-Induced Disease.

Directory of Open Access Journals (Sweden)

Aayushi Uberoi

2016-05-01

Full Text Available Human papillomaviruses are causally associated with 5% of human cancers. The recent discovery of a papillomavirus (MmuPV1 that infects laboratory mice provides unique opportunities to study the life cycle and pathogenesis of papillomaviruses in the context of a genetically manipulatable host organism. To date, MmuPV1-induced disease has been found largely to be restricted to severely immunodeficient strains of mice. In this study, we report that ultraviolet radiation (UVR, specifically UVB spectra, causes wild-type strains of mice to become highly susceptible to MmuPV1-induced disease. MmuPV1-infected mice treated with UVB develop warts that progress to squamous cell carcinoma. Our studies further indicate that UVB induces systemic immunosuppression in mice that correlates with susceptibility to MmuPV1-associated disease. These findings provide new insight into how MmuPV1 can be used to study the life cycle of papillomaviruses and their role in carcinogenesis, the role of host immunity in controlling papillomavirus-associated pathogenesis, and a basis for understanding in part the role of UVR in promoting HPV infection in humans.

HPV16-E2 induces prophase arrest and activates the cellular DNA damage response in vitro and in precursor lesions of cervical carcinoma.

Science.gov (United States)

Xue, Yuezhen; Toh, Shen Yon; He, Pingping; Lim, Thimothy; Lim, Diana; Pang, Chai Ling; Abastado, Jean-Pierre; Thierry, Françoise

2015-10-27

Cervical intraepithelial neoplasia (CIN) is caused by human papillomavirus (HPV) infection and is the precursor to cervical carcinoma. The completion of the HPV productive life cycle depends on the expression of viral proteins which further determines the severity of the cervical neoplasia. Initiation of the viral productive replication requires expression of the E2 viral protein that cooperates with the E1 viral DNA helicase. A decrease in the viral DNA replication ability and increase in the severity of cervical neoplasia is accompanied by simultaneous elevated expression of E6 and E7 oncoproteins. Here we reveal a novel and important role for the HPV16-E2 protein in controlling host cell cycle during malignant transformation. We showed that cells expressing HPV16-E2 in vitro are arrested in prophase alongside activation of a sustained DDR signal. We uncovered evidence that HPV16-E2 protein is present in vivo in cells that express both mitotic and DDR signals specifically in CIN3 lesions, immediate precursors of cancer, suggesting that E2 may be one of the drivers of genomic instability and carcinogenesis in vivo.

Prevalence of the integration status for human papillomavirus 16 in esophageal carcinoma samples.

Science.gov (United States)

Li, Shuying; Shen, Haie; Li, Ji; Hou, Xiaoli; Zhang, Ke; Li, Jintao

2018-03-01

To investigate the etiology of esophageal cancer (EC) related with human papillomavirus (HPV) infection. Fresh surgically resected tissue samples and clinical information were obtained from 189 patients. Genomic DNA was extracted, and HPV was detected using polymerase chain reaction (PCR) with HPV L1 gene primers of MY09/11; HPV16 was detected using HPV16 E6 type-specific primer sets. Copies of HPV16 E2, E6, and the human housekeeping gene β-actin were tested using quantitative PCR to analyze the relationship between HPV16 integration and esophageal squamous cell carcinoma and the relationship between the HPV16 integration status and clinical information of patients. Of the 189 samples, 168 HPV-positive samples were detected, of which 76 were HPV16 positive. Among the HPV16 positive samples, 2 cases (E2/E6 ratio>1) were 2.6% (2/76) purely episomal, 65 (E2/E6 ratio between 0 and 1) were 85.6% (65/76) mixture of integrated and episomal, and 9 (E2/E6 ratio=0) were 11.8% (9/76) purely integrated. The results indicate that integration of HPV16 was more common in the host genome than in the episome genome. The prevalence rate of HPV16 integration is increasing with the pathological stage progression of esophageal carcinoma (EC). A high prevalence of HPV16 suggested that HPV16 has an etiological effect on the progress of EC. Integration of HPV16 is more common than episome genome in the host cells, indicating that continuous HPV infection is the key to esophageal epithelial cell malignant conversion and canceration.

Proteins of bacteriophage phi6

International Nuclear Information System (INIS)

Sinclair, J.F.; Tzagoloff, A.; Levine, D.; Mindich, L.

1975-01-01

We investigated the protein composition of the lipid-containing bacteriophage phi 6. We also studied the synthesis of phage-specific proteins in the host bacterium Pseudomonas phaseolicola HB10Y. The virion was found to contain 10 proteins of the following molecular weights: P1, 93,000; P2, 88,000; P3, 84,000; P4, 36,800; P5, 24,000; P6, 21,000; P7, 19,900; P8, 10,500; P9, 8,700; and P10, less than 6,000. Proteins P3, P9, and P10 were completely extracted from the virion with 1 percent Triton X-100. Protein P6 was partially extracted. Proteins P8 and P9 were purified by column chromatography. The amino acid composition of P9 was determined and was found to lack methionine. Labeling of viral proteins with [ 35 S]methionine in infected cells indicated that proteins P5, P9, P10, and P11 lacked methionine. Treatment of host cells with uv light before infection allowed the synthesis of P1, P2, P4, and P7; however, the extent of viral protein synthesis fell off exponentially with increasing delay time between irradiation and infection. Treatment of host cells with rifampin during infection allowed preferential synthesis of viral proteins, but the extent of synthesis also fell off exponentially with increasing delay time between the addition of rifampin and the addition of radioactive amino acids. All of the virion proteins were seen in gels prepared from rifampin-treated infected cells. In addition, two proteins, P11 and P12, were observed; their molecular weights were 25,200 and 20,100, respectively. Proteins P1, P2, P4, and P7 were synthesized early, whereas the rest began to increase at 45 min post-infection

Cervical Cancer Incidence in Young U.S. Females After Human Papillomavirus Vaccine Introduction.

Science.gov (United States)

Guo, Fangjian; Cofie, Leslie E; Berenson, Abbey B

2018-05-30

Since 2006, human papillomavirus vaccine has been recommended for young females in the U.S. This study aimed to compare cervical cancer incidence among young women before and after the human papillomavirus vaccine was introduced. This cross-sectional study used data from the National Program for Cancer Registries and Surveillance, Epidemiology, and End Results Incidence-U.S. Cancer Statistics 2001-2014 database for U.S. females aged 15-34 years. This study compared the 4-year average annual incidence of invasive cervical cancer in the 4 years before human papillomavirus vaccine was introduced (2003-2006) and the 4 most recent years in the vaccine era (2011-2014). Joinpoint regression models of cervical incidence from 2001 to 2014 were fitted to identify the discrete joints (year) that represent statistically significant changes in the direction of the trend after the introduction of human papillomavirus vaccination in 2006. Data were collected in 2001-2014, released, and analyzed in 2017. The 4-year average annual incidence rates for cervical cancer in 2011-2014 were 29% lower than that in 2003-2006 (6.0 vs 8.4 per 1,000,000 people, rate ratio=0.71, 95% CI=0.64, 0.80) among females aged 15-24 years, and 13.0% lower among females aged 25-34 years. Joinpoint analyses of cervical cancer incidence among females aged 15-24 years revealed a significant joint at 2009 for both squamous cell carcinoma and non-squamous cell carcinoma. Among females aged 25-34 years, there was no significant decrease in cervical cancer incidence after 2006. A significant decrease in the incidence of cervical cancer among young females after the introduction of human papillomavirus vaccine may indicate early effects of human papillomavirus vaccination. Copyright © 2018 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

The Tetraspanin CD151 in Papillomavirus Infection

Directory of Open Access Journals (Sweden)

Konstanze D. Scheffer

2014-02-01

Full Text Available Human papillomaviruses (HPV are non-enveloped DNA tumor viruses that infect skin and mucosa. The most oncogenic subtype, HPV16, causes various types of cancer, including cervical, anal, and head and neck cancers. During the multistep process of infection, numerous host proteins are required for the delivery of virus genetic information into the nucleus of target cells. Over the last two decades, many host-cell proteins such as heparan sulfate proteoglycans, integrins, growth factor receptors, actin and the tetraspanin CD151 have been described to be involved in the process of infectious entry of HPV16. Tetraspanins have the ability to organize membrane microdomains and to directly influence the function of associated molecules, including binding of receptors to their ligands, receptor oligomerization and signal transduction. Here, we summarize the current knowledge on CD151, and CD151-associated partners during HPV infection and discuss the underlying mechanisms.

A prime/boost strategy using DNA/fowlpox recombinants expressing the genetically attenuated E6 protein as a putative vaccine against HPV-16-associated cancers.

Science.gov (United States)

Bissa, Massimiliano; Illiano, Elena; Pacchioni, Sole; Paolini, Francesca; Zanotto, Carlo; De Giuli Morghen, Carlo; Massa, Silvia; Franconi, Rosella; Radaelli, Antonia; Venuti, Aldo

2015-03-05

Considering the high number of new cases of cervical cancer each year that are caused by human papilloma viruses (HPVs), the development of an effective vaccine for prevention and therapy of HPV-associated cancers, and in particular against the high-risk HPV-16 genotype, remains a priority. Vaccines expressing the E6 and E7 proteins that are detectable in all HPV-positive pre-cancerous and cancer cells might support the treatment of HPV-related lesions and clear already established tumors. In this study, DNA and fowlpox virus recombinants expressing the E6F47R mutant of the HPV-16 E6 oncoprotein were generated, and their correct expression verified by RT-PCR, Western blotting and immunofluorescence. Immunization protocols were tested in a preventive or therapeutic pre-clinical mouse model of HPV-16 tumorigenicity using heterologous (DNA/FP) or homologous (DNA/DNA and FP/FP) prime/boost regimens. The immune responses and therapeutic efficacy were evaluated by ELISA, ELISPOT assays, and challenge with TC-1* cells. In the preventive protocol, while an anti-E6-specific humoral response was just detectable, a specific CD8(+) cytotoxic T-cell response was elicited in immunized mice. After the challenge, there was a delay in cancer appearance and a significant reduction of tumor volume in the two groups of E6-immunized mice, thus confirming the pivotal role of the CD8(+) T-cell response in the control of tumor growth in the absence of E6-specific antibodies. In the therapeutic protocol, in-vivo experiments resulted in a higher number of tumor-free mice after the homologous DNA/DNA or heterologous DNA/FP immunization. These data establish a preliminary indication for the prevention and treatment of HPV-related tumors by the use of DNA and avipox constructs as safe and effective immunogens following a prime/boost strategy. The combined use of recombinants expressing both E6 and E7 proteins might improve the antitumor efficacy, and should represent an important approach to

Interferon-β induced microRNA-129-5p down-regulates HPV-18 E6 and E7 viral gene expression by targeting SP1 in cervical cancer cells.

Directory of Open Access Journals (Sweden)

Jiarong Zhang

Full Text Available Infection by human papillomavirus (HPV can cause cervical intraepithelial neoplasia (CIN and cancer. Down-regulation of E6 and E7 expression may be responsible for the positive clinical outcomes observed with IFN treatment, but the molecular basis has not been well determined. As miRNAs play an important role in HPV induced cervical carcinogenesis, we hypothesize that IFN-β can regulate the expressions of specific miRNAs in cervical cancer cells, and that these miRNAs can mediate E6 and E7 expression, thus modulate their oncogenic potential. In this study, we found that miR-129-5p to be a candidate IFN-β inducible miRNA. MiR-129-5p levels gradually decrease with the development of cervical intraepithelial lesions. Manipulation of miR-129-5p expression in Hela cells modulates HPV-18 E6 and E7 viral gene expression. Exogenous miR-129-5p inhibits cell proliferation in Hela cells, promotes apoptosis and blocks cell cycle progression in Hela cells. SP1 is a direct target of miR-129-5p in Hela cells. This study is the first report of a cellular miRNA with anti-HPV activity and provides new insights into regulatory mechanisms between the HPV and the IFN system in host cells at the miRNA level.

Comparative transforming potential of different human papillomaviruses associated with non-melanoma skin cancer

International Nuclear Information System (INIS)

Massimi, Paola; Thomas, Miranda; Bouvard, Veronique; Ruberto, Irene; Campo, M. Saveria; Tommasino, Massimo; Banks, Lawrence

2008-01-01

It is well established that high-risk human papillomaviruses (HPVs) that infect mucosal epithelia are the causative agents of cervical cancer. In contrast, the association of cutaneo-tropic HPV types with the development of non-melanoma skin cancer (NMSC) is less well defined. In this study, we have analysed the in vitro transforming potential of various cutaneous HPV types. Using oncogene cooperation assays with activated ras, we have shown that diverse cutaneous types, including 12, 14, 15, 24, 36 and 49, have significant transforming potential. Interestingly, most of this activity appears to be encoded by the E6 gene product. In contrast, the common HPV-10 exhibits no significant transforming potential in these assays. This difference may be a reflection of different patterns of cellular localization, with transforming E6s being nuclear and non-transforming being cytoplasmic. These results provide molecular support for a role of these viruses in the development of certain human malignancies

HPV (Human Papillomavirus) vaccine - what you need to know

Science.gov (United States)

... is taken in its entirety from the CDC HPV (Human Papillomavirus) Vaccine Information Statement (VIS): www.cdc.gov/vaccines/hcp/vis/vis-statements/hpv.html . CDC review information for HPV (Human Papillomavirus) ...

Role of Human Papillomavirus in Penile Carcinomas Worldwide.

Science.gov (United States)

Alemany, Laia; Cubilla, Antonio; Halec, Gordana; Kasamatsu, Elena; Quirós, Beatriz; Masferrer, Emili; Tous, Sara; Lloveras, Belén; Hernández-Suarez, Gustavo; Lonsdale, Ray; Tinoco, Leopoldo; Alejo, Maria; Alvarado-Cabrero, Isabel; Laco, Jan; Guimerà, Nuria; Poblet, Enrique; Lombardi, Luis E; Bergeron, Christine; Clavero, Omar; Shin, Hai-Rim; Ferrera, Annabelle; Felix, Ana; Germar, Julieta; Mandys, Vaclav; Clavel, Christine; Tzardi, Maria; Pons, Luis E; Wain, Vincent; Cruz, Eugenia; Molina, Carla; Mota, Jose D; Jach, Robert; Velasco, Julio; Carrilho, Carla; López-Revilla, Ruben; Goodman, Marc T; Quint, Wim G; Castellsagué, Xavier; Bravo, Ignacio; Pawlita, Michael; Muñoz, Nubia; Bosch, F Xavier; de Sanjosé, Silvia

2016-05-01

Invasive penile cancer is a rare disease with an approximately 22 000 cases per year. The incidence is higher in less developed countries, where penile cancer can account for up to 10% of cancers among men in some parts of Africa, South America, and Asia. To describe the human papillomavirus (HPV) DNA prevalence, HPV type distribution, and detection of markers of viral activity (ie, E6*I mRNA and p16(INK4a)) in a series of invasive penile cancers and penile high-grade squamous intraepithelial lesions (HGSILs) from 25 countries. A total of 85 penile HGSILs and 1010 penile invasive cancers diagnosed from 1983 to 2011 were included. After histopathologic evaluation of formalin-fixed paraffin-embedded samples, HPV DNA detection and genotyping were performed using the SPF-10/DEIA/LiPA25 system, v.1 (Laboratory Biomedical Products, Rijswijk, The Netherlands). HPV DNA-positive cases were additionally tested for oncogene E6*I mRNA and all cases for p16(INK4a) expression, a surrogate marker of oncogenic HPV activity. HPV DNA prevalence and type distributions were estimated. HPV DNA was detected in 33.1% of penile cancers (95% confidence interval [CI], 30.2-36.1) and in 87.1% of HGSILs (95% CI, 78.0-93.4). The warty-basaloid histologic subtype showed the highest HPV DNA prevalence. Among cancers, statistically significant differences in prevalence were observed only by geographic region and not by period or by age at diagnosis. HPV16 was the most frequent HPV type detected in both HPV-positive cancers (68.7%) and HGSILs (79.6%). HPV6 was the second most common type in invasive cancers (3.7%). The p16(INK4a) upregulation and mRNA detection in addition to HPV DNA positivity were observed in 69.3% of HGSILs, and at least one of these HPV activity markers was detected in 85.3% of cases. In penile cancers, these figures were 22.0% and 27.1%, respectively. About a third to a fourth of penile cancers were related to HPV when considering HPV DNA detection alone or adding an HPV

The association between human papillomavirus and oropharyngeal squamous cell Carcinoma

DEFF Research Database (Denmark)

Walvik, Lena; Svensson, Amanda Björk; Friborg, Jeppe

2016-01-01

carcinoma using the Bradford Hill criteria. The strength of the association is supported by, detection of human papillomavirus infection and antibodies prior to oropharyngeal squamous cell carcinoma. This is furthermore reinforced by the absence of human papillomavirus DNA in healthy tonsils...... incidence in human papillomavirus positive oropharyngeal squamous cell carcinoma is associated with sexual behaviour. These associations have been repeatedly observed and are in accordance with our current knowledge. The time relation between cause and effect remains the main challenge, due to the lack...... of well-defined premalignant lesions. However, a causal relationship between human papillomavirus infection and oropharyngeal squamous cell carcinoma seems evident....

The Host E3-Ubiquitin Ligase TRIM6 Ubiquitinates the Ebola Virus VP35 Protein and Promotes Virus Replication.

Science.gov (United States)

Bharaj, Preeti; Atkins, Colm; Luthra, Priya; Giraldo, Maria Isabel; Dawes, Brian E; Miorin, Lisa; Johnson, Jeffrey R; Krogan, Nevan J; Basler, Christopher F; Freiberg, Alexander N; Rajsbaum, Ricardo

2017-09-15

Ebola virus (EBOV), a member of the Filoviridae family, is a highly pathogenic virus that causes severe hemorrhagic fever in humans and is responsible for epidemics throughout sub-Saharan, central, and West Africa. The EBOV genome encodes VP35, an important viral protein involved in virus replication by acting as an essential cofactor of the viral polymerase as well as a potent antagonist of the host antiviral type I interferon (IFN-I) system. By using mass spectrometry analysis and coimmunoprecipitation assays, we show here that VP35 is ubiquitinated on lysine 309 (K309), a residue located on its IFN antagonist domain. We also found that VP35 interacts with TRIM6, a member of the E3-ubiquitin ligase tripartite motif (TRIM) family. We recently reported that TRIM6 promotes the synthesis of unanchored K48-linked polyubiquitin chains, which are not covalently attached to any protein, to induce efficient antiviral IFN-I-mediated responses. Consistent with this notion, VP35 also associated noncovalently with polyubiquitin chains and inhibited TRIM6-mediated IFN-I induction. Intriguingly, we also found that TRIM6 enhances EBOV polymerase activity in a minigenome assay and TRIM6 knockout cells have reduced replication of infectious EBOV, suggesting that VP35 hijacks TRIM6 to promote EBOV replication through ubiquitination. Our work provides evidence that TRIM6 is an important host cellular factor that promotes EBOV replication, and future studies will focus on whether TRIM6 could be targeted for therapeutic intervention against EBOV infection. IMPORTANCE EBOV belongs to a family of highly pathogenic viruses that cause severe hemorrhagic fever in humans and other mammals with high mortality rates (40 to 90%). Because of its high pathogenicity and lack of licensed antivirals and vaccines, EBOV is listed as a tier 1 select-agent risk group 4 pathogen. An important mechanism for the severity of EBOV infection is its suppression of innate immune responses. The EBOV VP35

Safety and Efficacy Data on Vaccines and Immunization to Human Papillomavirus

Directory of Open Access Journals (Sweden)

Natalie Kash

2015-04-01

Full Text Available Since the discovery of the causal association between human papillomavirus (HPV and cervical cancer, efforts to develop an effective prophylactic vaccine to prevent high-risk HPV infections have been at the forefront of modern medical research. HPV causes 530,000 cervical cancer cases worldwide, which is the second most common cause of cancer deaths in women; a worldwide collaboration among epidemiologists, molecular biologists, vaccinologists, virologists, and clinicians helped lead to the development of two highly effective prophylactive HPV vaccines. The first, Gardasil, is a quadrivalent vaccine made up of recombinant HPV L1 capsid proteins from the two high-risk HPV types (16/18 responsible for 70% of cervical cancer cases as well as two low-risk HPV types (6/11 which are the causative agent for genital warts. The second, Cervarix, is a bivalent vaccine that was FDA approved three years after Gardasil and is also composed of L1 capsid proteins from HPV types 16/18. This review article focuses on the safety and efficacy data of both FDA-approved vaccines, as well as highlighting a few advances in future HPV vaccines that show promise in becoming additional treatment options for this worldwide disease.

Prime-boost therapeutic vaccination in mice with DNA/DNA or DNA/Fowlpox virus recombinants expressing the Human Papilloma Virus type 16 E6 and E7 mutated proteins fused to the coat protein of Potato virus X.

Science.gov (United States)

Illiano, Elena; Bissa, Massimiliano; Paolini, Francesca; Zanotto, Carlo; De Giuli Morghen, Carlo; Franconi, Rosella; Radaelli, Antonia; Venuti, Aldo

2016-10-02

The therapeutic antitumor potency of a prime-boost vaccination strategy was explored, based on the mutated, nontransforming forms of the E6 (E6 F47R ) and E7 (E7 GGG ) oncogenes of Human Papilloma Virus type 16 (HPV16), fused to the Potato virus X (PVX) coat protein (CP) sequence. Previous data showed that CP fusion improves the immunogenicity of tumor-associated antigens and may thus increase their efficacy. After verifying the correct expression of E6 F47R CP and E7 GGG CP inserted into DNA and Fowlpox virus recombinants by Western blotting and immunofluorescence, their combined use was evaluated for therapy in a pre-clinical mouse model of HPV16-related tumorigenicity. Immunization protocols were applied using homologous (DNA/DNA) or heterologous (DNA/Fowlpox) prime-boost vaccine regimens. The humoral immune responses were determined by ELISA, and the therapeutic efficacy evaluated by the delay in tumor appearance and reduced tumor volume after inoculation of syngeneic TC-1* tumor cells. Homologous DNA/DNA genetic vaccines were able to better delay tumor appearance and inhibit tumor growth when DNAE6 F47R CP and DNAE7 GGG CP were administered in combination. However, the heterologous DNA/Fowlpox vaccination strategy was able to delay tumor appearance in a higher number of animals when E6 F47R CP and in particular E7 GGG CP were administered alone. Copyright © 2016 Elsevier B.V. All rights reserved.

A prospective study of women with ASCUS or LSIL pap smears at baseline and HPV E6/E7 mRNA positive: a 3-year follow-up.

Science.gov (United States)

Bruno, M T; Ferrara, M; Fava, V; Barrasso, G; Panella, M M

2018-04-01

Human papillomavirus (HPV) testing is used in the triage of women with a borderline smear result. The efficiency of testing women with a low-grade squamous intraepithelial lesion (LSIL) and atypical squamous cells of undetermined significance (ASCUS) is less clear. For this reason we used a new HPV test that detects E6/E7 messenger RNA (mRNA), which might have a higher specificity. The objective of this prospective study was to assess whether HPV E6/E7 mRNA positivity in women with ASCUS and LSIL at baseline, is able to predict those women who have a high risk of developing a histological cervical intraepithelial neoplasia (CIN2) or worse lesion. We took into consideration the women's age and HPV DNA genotype and followed them up for 3 years. Cervical samples from women with high-risk HPV (HR-HPV) DNA-positive ASCUS (n = 90) or LSIL (n = 222) were tested for the presence of HR-HPV E6/E7 mRNA and the women were monitored for the development of histopathologically verified CIN2+. Thirteen patients with ASCUS and 17 with LSIL did not complete follow-up. All patients with LSIL and ASCUS, enrolled in this study, had confirmed lesions at the colposcopic examination. Follow-up was available for 312 women, 193 were positive in the HR-HPV DNA test and 93 had a HPV E6/E7 mRNA positive test. Finally, 22 women positive in the HPV DNA test for high-risk genotypes and with positive E6/E7 mRNA had a histologically confirmed CIN2+. Only two cases with negative HPV E6/E7 mRNA had CIN2+. The study shows that women positive in the HPV E6/E7 mRNA test have a greater risk of malignant progression of cervical lesions and therefore deserve greater attention and earlier check-ups.

Concordant testing results between various Human Papillomavirus assays in primary cervical cancer screening

DEFF Research Database (Denmark)

de Thurah, Lena; Bonde, Jesper; Hoa Lam, Janni Uyen

2018-01-01

OBJECTIVES: Human Papillomavirus (HPV) assays are increasingly used for primary cervical screening and HPV vaccination effect monitoring. We undertook a systematic literature review to determine the concordance in positive test results (i.e., detection of HPV infections) between Hybrid Capture 2 ...

Human papillomavirus and tumours of the eye region

DEFF Research Database (Denmark)

Sjö, Nicolai Christian

2005-01-01

ophthalmology, lacrimal sac, tear sac, papilloma, carcinoma, papillomavirus, HPV, polymerase chain reaction, PCR, RNA, DNA, in situ hybridisation, aetiology, conjunctiva, dysplasia, sex, age, distribution......ophthalmology, lacrimal sac, tear sac, papilloma, carcinoma, papillomavirus, HPV, polymerase chain reaction, PCR, RNA, DNA, in situ hybridisation, aetiology, conjunctiva, dysplasia, sex, age, distribution...

Increased p50/p50 NF-κB Activation in Human Papillomavirus Type 6- or Type 11-Induced Laryngeal Papilloma Tissue

Science.gov (United States)

Vancurova, Ivana; Wu, Rong; Miskolci, Veronika; Sun, Shishinn

2002-01-01

We have observed elevated NF-κB DNA-binding activity in nuclear extracts from human papillomavirus type 6- and 11-infected laryngeal papilloma tissues. The predominant DNA-binding species is the p50/p50 homodimer. The elevated NF-κB activity could be correlated with a reduced level of cytoplasmic IκBβ and could be associated with the overexpression of p21CIP1/WAF1 in papilloma cells. Increased NF-κB activity and cytoplasmic accumulation of p21CIP1/WAF1 might counteract death-promoting effects elicited by overexpressed PTEN and reduced activation of Akt and STAT3 previously noted in these tissues. PMID:11773428

Human Papillomavirus Regulates HER3 Expression in Head and Neck Cancer: Implications for Targeted HER3 Therapy in HPV+ Patients.

Science.gov (United States)

Brand, Toni M; Hartmann, Stefan; Bhola, Neil E; Peyser, Noah D; Li, Hua; Zeng, Yan; Isaacson Wechsler, Erin; Ranall, Max V; Bandyopadhyay, Sourav; Duvvuri, Umamaheswar; LaVallee, Theresa M; Jordan, Richard C K; Johnson, Daniel E; Grandis, Jennifer R

2017-06-15

Purpose: Human papillomavirus (HPV) 16 plays an etiologic role in a growing subset of head and neck squamous cell carcinomas (HNSCC), where viral expression of the E6 and E7 oncoproteins is necessary for tumor growth and maintenance. Although patients with HPV + tumors have a more favorable prognosis, there are currently no HPV-selective therapies. Recent studies identified differential receptor tyrosine kinase (RTK) profiles in HPV + versus HPV - tumors. One such RTK, HER3, is overexpressed and interacts with phosphoinositide-3-kinase (PI3K) in HPV + tumors. Therefore, we investigated the role of HPV oncoproteins in regulating HER3-mediated signaling and determined whether HER3 could be a molecular target in HPV + HNSCC. Experimental Design: HER3 was investigated as a molecular target in HPV + HNSCC using established cell lines, patient-derived xenografts (PDX), and human tumor specimens. A mechanistic link between HPV and HER3 was examined by augmenting E6 and E7 expression levels in HNSCC cell lines. The dependency of HPV + and HPV - HNSCC models on HER3 was evaluated with anti-HER3 siRNAs and the clinical stage anti-HER3 monoclonal antibody KTN3379. Results: HER3 was overexpressed in HPV + HNSCC, where it was associated with worse overall survival in patients with pharyngeal cancer. Further investigation indicated that E6 and E7 regulated HER3 protein expression and downstream PI3K pathway signaling. Targeting HER3 with siRNAs or KTN3379 significantly inhibited the growth of HPV + cell lines and PDXs. Conclusions: This study uncovers a direct relationship between HPV infection and HER3 in HNSCC and provides a rationale for the clinical evaluation of targeted HER3 therapy for the treatment of HPV + patients. Clin Cancer Res; 23(12); 3072-83. ©2016 AACR . ©2016 American Association for Cancer Research.

The nonstructural protein 8 (nsp8) of the SARS coronavirus interacts with its ORF6 accessory protein

International Nuclear Information System (INIS)

Kumar, Purnima; Gunalan, Vithiagaran; Liu Boping; Chow, Vincent T.K.; Druce, Julian; Birch, Chris; Catton, Mike; Fielding, Burtram C.; Tan, Yee-Joo; Lal, Sunil K.

2007-01-01

Severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV) caused a severe outbreak in several regions of the world in 2003. The SARS-CoV genome is predicted to contain 14 functional open reading frames (ORFs). The first ORF (1a and 1b) encodes a large polyprotein that is cleaved into nonstructural proteins (nsp). The other ORFs encode for four structural proteins (spike, membrane, nucleocapsid and envelope) as well as eight SARS-CoV-specific accessory proteins (3a, 3b, 6, 7a, 7b, 8a, 8b and 9b). In this report we have cloned the predicted nsp8 gene and the ORF6 gene of the SARS-CoV and studied their abilities to interact with each other. We expressed the two proteins as fusion proteins in the yeast two-hybrid system to demonstrate protein-protein interactions and tested the same using a yeast genetic cross. Further the strength of the interaction was measured by challenging growth of the positive interaction clones on increasing gradients of 2-amino trizole. The interaction was then verified by expressing both proteins separately in-vitro in a coupled-transcription translation system and by coimmunoprecipitation in mammalian cells. Finally, colocalization experiments were performed in SARS-CoV infected Vero E6 mammalian cells to confirm the nsp8-ORF6 interaction. To the best of our knowledge, this is the first report of the interaction between a SARS-CoV accessory protein and nsp8 and our findings suggest that ORF6 protein may play a role in virus replication

The Epstein-Barr virus nuclear antigen-6 protein co-localizes with EBNA-3 and survival of motor neurons protein

International Nuclear Information System (INIS)

Krauer, Kenia G.; Buck, Marion; Belzer, Deanna K.; Flanagan, James; Chojnowski, Grace M.; Sculley, Tom B.

2004-01-01

The Epstein-Barr virus nuclear antigen (EBNA)-6 protein is essential for Epstein-Barr virus (EBV)-induced immortalization of primary human B-lymphocytes in vitro. In this study, fusion proteins of EBNA-6 with green fluorescent protein (GFP) have been used to characterize its nuclear localization and organization within the nucleus. EBNA-6 associates with nuclear structures and in immunofluorescence demonstrate a punctate staining pattern. Herein, we show that the association of EBNA-6 with these nuclear structures was maintained throughout the cell cycle and with the use of GFP-E6 deletion mutants, that the region amino acids 733-808 of EBNA-6 contains a domain that can influence the association of EBNA-6 with these nuclear structures. Co-immunofluorescence and confocal analyses demonstrated that EBNA-6 and EBNA-3 co-localize in the nucleus of cells. Expression of EBNA-6, but not EBNA-3, caused a redistribution of nuclear survival of motor neurons protein (SMN) to the EBNA-6 containing nuclear structures resulting in co-localization of SMN with EBNA-6

Identification of a 450-bp region of human papillomavirus type 1 that promotes episomal replication in Saccharomyces cerevisiae

International Nuclear Information System (INIS)

Chattopadhyay, Anasuya; Schmidt, Martin C.; Khan, Saleem A.

2005-01-01

Human papillomaviruses (HPVs) replicate as nuclear plasmids in infected cells. Since the DNA replication machinery is generally conserved between humans and Saccharomyces cerevisiae, we studied whether HPV-1 DNA can replicate in yeast. Plasmids containing a selectable marker (with or without a yeast centromere) and either the full-length HPV-1 genome or various regions of the viral long control region (LCR) and the 3' end of the L1 gene were introduced into S. cerevisiae and their ability to replicate episomally was investigated. Our results show that HPV-1 sequences promote episomal replication of plasmids although the yeast centromere is required for plasmid retention. We have mapped the autonomously replicating sequence activity of HPV-1 DNA to a 450 base-pair sequence (HPV-1 nt 6783-7232) that includes 293 nucleotides from the 5' region of the viral LCR and 157 nucleotides from the 3' end of the L1 gene. The HPV-1 ARS does not include the binding sites for the viral E1 and E2 proteins, and these proteins are dispensable for replication in S. cerevisiae

Infection with the oncogenic human papillomavirus type 59 alters protein components of the cornified cell envelope

International Nuclear Information System (INIS)

Lehr, Elizabeth; Brown, Darron R.

2003-01-01

Infection of the genital tract with human papillomaviruses (HPVs) leads to proliferative and dysplastic epithelial lesions. The mechanisms used by the virus to escape the infected keratinocyte are not well understood. Infection of keratinocytes with HPV does not cause lysis, the mechanism used by many viruses to release newly formed virions. For HPV 11, a type associated with a low risk of neoplastic disease, the cornified cell envelope (CCE) of infected keratinocytes is thin and fragile, and transcription of loricrin, the major CCE protein, is reduced. The effects of high-risk HPV infection on components of the CCE have not been previously reported. HPV 59, an oncogenic genital type related to HPV types 18 and 45 was identified in a condylomata acuminata lesion. An extract of this lesion was used to infect human foreskin fragments, which were grown in athymic mice as xenografts. Continued propagation using extracts of xenografts permitted growth of additional HPV 59-infected xenografts. CCEs purified from HPV 59-infected xenografts displayed subtle morphologic abnormalities compared to those derived from uninfected xenografts. HPV 59-infected xenografts revealed dysplastic-appearing cells with mitotic figures. Detection of loricrin, involucrin, and cytokeratin 10 was reduced in HPV 59-infected epithelium, while small proline-rich protein 3 (SPR3) was increased. Reduction in loricrin was most apparent in regions of epithelium containing abundant HPV 59 DNA. Compared to uninfected epithelium, loricrin transcription was decreased in HPV 59-infected epithelium. We conclude that HPV 59 shares with HPV 11 the ability to alter CCE components and to specifically reduce transcription of the loricrin gene. Because loricrin is the major CCE protein, a reduction in this component could alter the physical properties of the CCE, thus facilitating virion release

The clinical value of HPV E6/E7 and STAT3 mRNA detection in cervical cancer screening.

Science.gov (United States)

Fan, Yibing; Shen, Zongji

2018-02-11

To explore the value of human papillomavirus (HPV) E6/E7 and signal transducer and activator of transcription 3 (STAT3) mRNA detection in the screening of cervical lesions. 192 patients with abnormal ThinPrep cytology test (TCT) results and/or high-risk HPV infection were screened to identify possible cervical lesions in cases. Diagnoses were confirmed by histopathology. Fluorescence in situ hybridization (FISH) was performed to detect and qualify the mRNAs of HPV E6/E7, STAT3, and Survivin in cervical exfoliated cells. In addition, the performance of separate and combined mRNA detection methods were compared with TCT, HR-HPV DNA schemes respectively. 1. Compared with HPVE6/E7 and STAT3 mRNA methods, Survivin mRNA assay had poor specificity (Sp), Youden index (YI) and concordance rate. 2. HPV E6/E7, STAT3, and STAT3 + HR-HPV methods had the best Sp, concordance rate and positive predictive value (PPV) for cervical lesions screening and atypical squamous cells of undetermined significance (ASCUS) triage. For screening of high grade squamous intraepithelial lesions or greater (HSILs+), no difference was observed in the Se of mRNA detection methods in comparison with that of TCT, HR-HPV and TCT + HR-HPV, whereas the false positive rate (FPR) decreased by 41.48%/55.99%/17.19% and the colposcopy referral rate reduced by about 20.00%/25.00%/11.17%. For triage of women with ASCUS, no difference was observed in the Se of mRNA detection methods as compared to that of HR-HPV (χ 2  = 1.05, P > 0.75), while the FPR decreased by 45.83%/37.50%/41.66% and the colposcopy referral rate reduced by 32.42%/22.60%/25.28%, respectively. The Se, YI, and PPV of the combined methods increased in comparison to each method alone. 3. Compared with the TCT + HR-HPV method, HPV E6/E7 + STAT3 method had perfect Sp (95.92%) and PPV (95.40%) for screening HSILs+, the FPR and colposcopy referral rate decreased by 31.06% and 22.48% respectively. 1. The expression of HPV E6/E

Human Papillomavirus (HPV) Vaccines

Science.gov (United States)

... factors for developing them, such as taking oral contraceptives . A safety review of Gardasil in Denmark and ... and venous thromboembolic adverse events after immunisation of adolescent girls with quadrivalent human papillomavirus vaccine in Denmark ...

Development of a next generation Semliki Forest virus-based DNA vaccine against cervical cancer

NARCIS (Netherlands)

Van De Wall, Stephanie; Ljungberg, Karl; Peng IP, Peng; Boerma, Annemarie; Nijman, Hans W.; Liljeström, Peter; Daemen, Toos

2014-01-01

Cervical cancer is the second most prevalent cancer among women worldwide. The disease develops as a result of infection with high-risk human papillomavirus (HPV) through persistent expression of early proteins E6 and E7 with transforming capacities in cervical epithelial cells. Our group pioneered

The interplay of UV and cutaneous papillomavirus infection in skin cancer development.

Directory of Open Access Journals (Sweden)

Daniel Hasche

2017-11-01

Full Text Available Cutaneous human papillomaviruses (HPVs are considered as cofactors for non-melanoma skin cancer (NMSC development, especially in association with UVB. Extensively studied transgenic mouse models failed to mimic all aspects of virus-host interactions starting from primary infection to the appearance of a tumor. Using the natural model Mastomys coucha, which reflects the human situation in many aspects, we provide the first evidence that only UVB and Mastomys natalensis papillomavirus (MnPV infection strongly promote NMSC formation. Using UVB exposures that correspond to UV indices of different geographical regions, irradiated animals developed either well-differentiated keratinizing squamous cell carcinomas (SCCs, still supporting productive infections with high viral loads and transcriptional activity, or poorly differentiated non-keratinizing SCCs almost lacking MnPV DNA and in turn, early and late viral transcription. Intriguingly, animals with the latter phenotype, however, still showed strong seropositivity, clearly verifying a preceding MnPV infection. Of note, the mere presence of MnPV could induce γH2AX foci, indicating that viral infection without prior UVB exposure can already perturb genome stability of the host cell. Moreover, as shown both under in vitro and in vivo conditions, MnPV E6/E7 expression also attenuates the excision repair of cyclobutane pyrimidine dimers upon UVB irradiation, suggesting a viral impact on the DNA damage response. While mutations of Ras family members (e.g. Hras, Kras, and Nras were absent, the majority of SCCs harbored-like in humans-Trp53 mutations especially at two hot-spots in the DNA-binding domain, resulting in a loss of function that favored tumor dedifferentiation, counter-selective for viral maintenance. Such a constellation provides a reasonable explanation for making continuous viral presence dispensable during skin carcinogenesis as observed in patients with NMSC.

Absence of an association of human polyomavirus and papillomavirus infection with lung cancer in China: a nested case–control study

International Nuclear Information System (INIS)

Colombara, Danny V.; Manhart, Lisa E.; Carter, Joseph J.; Hawes, Stephen E.; Weiss, Noel S.; Hughes, James P.; Qiao, You-Lin; Taylor, Philip R.; Smith, Jennifer S.; Galloway, Denise A.

2016-01-01

Studies of human polyomavirus (HPyV) infection and lung cancer are limited and those regarding the association of human papillomavirus (HPV) infection and lung cancer have produced inconsistent results. We conducted a nested case–control study to assess the association between incident lung cancer of various histologies and evidence of prior infection with HPyVs and HPVs. We selected serum from 183 cases and 217 frequency matched controls from the Yunnan Tin Miner’s Cohort study, which was designed to identify biomarkers for early detection of lung cancer. Using multiplex liquid bead microarray (LBMA) antibody assays, we tested for antibodies to the VP1 structural protein and small T antigen (ST-Ag) of Merkel cell, KI, and WU HPyVs. We also tested for antibodies against HPV L1 structural proteins (high-risk types 16, 18, 31, 33, 52, and 58 and low-risk types 6 and 11) and E6 and E7 oncoproteins (high risk types 16 and 18). Measures of antibody reactivity were log transformed and analyzed using logistic regression. We found no association between KIV, WUV, and MCV antibody levels and incident lung cancer (P-corrected for multiple comparisons >0.10 for all trend tests). We also found no association with HPV-16, 18, 31, 33, 52, and 58 seropositivity (P-corrected for multiple comparisons >0.05 for all). Future studies of infectious etiologies of lung cancer should look beyond HPyVs and HPVs as candidate infectious agents. The online version of this article (doi:10.1186/s12885-016-2381-3) contains supplementary material, which is available to authorized users

Asociación molecular entre los papilomavirus y el cáncer de cérvix Molecular association between papillomavirus and cervix cancer

Directory of Open Access Journals (Sweden)

Jorge Eliécer Ossa Londoño

1996-04-01

Full Text Available Se revisa la patogénesis del condiloma y el cáncer inducidos por los papilomavirus (PVH, que puede resumirse así: a través de microheridas en el epitelio, el virus infecta las células basa les y en el proceso de cicatrización se activa la proliferación celular con lo que se permite iniciar el ciclo de replicación viral; el producto del gen viral E7 se une a la proteína celular Rb, liberando el factor E2F que induce a la célula a entrar en el ciclo de división. El estado proliferativo debería ser contrarrestado por una respuesta apoptótica que es mediada, en este tipo de células, por la proteína p53. El gen viral E6 inactiva esta proteína con lo que se permite la aparición del condiloma por desequilibrio entre la proliferación y la apoptosis. En el contexto de una replicación celular activa e incontrolada y con la proteína p53 inactivada para cumplir sus funciones proapoptóticas y reparadoras, es muy alta la probabilidad de aparición de una célula maligna. Este panorama se hace más complejo cuando los virus, eventualmente, se integran al genoma celular (10 que es más frecuente en el PVH tipo 18. En este caso el gen regulador E2 se inactiva y consecuentemente aumentan las proteínas E6 y E7. A review is presented on the pathogenesis of condiloma and cancer induced by papillomavirus infection: through minimal epithelial wounds these viruses reach basal cells; cell proliferation is activated in the healing process thereby allowing the viral replication cycle to take place. The product of viral gen E7 joins Rb cell protein releasing the factor (E2F that induces cell division. Proliferation should be opposed by apoptosis mediated by cell protein p53 but viral gen E6 inactivates the latter leading to an imbalance between cell division and death. With the occurrence of active, uncontrolled cell division the likelihood of malignancy development becomes high.

Arsenic trioxide inhibits cell proliferation and human papillomavirus oncogene expression in cervical cancer cells

International Nuclear Information System (INIS)

Wang, Hongtao; Gao, Peng; Zheng, Jie

2014-01-01

Highlights: • As 2 O 3 inhibits growth of cervical cancer cells and expression of HPV oncogenes in these cells. • HPV-negative cervical cancer cells are more sensitive to As 2 O 3 than HPV-positive cervical cancer cells. • HPV-18 positive cervical cancer cells are more sensitive to As 2 O 3 than HPV-16 positive cancer cells. • Down-regulation of HPV oncogenes by As 2 O 3 is partially due to the diminished AP-1 binding. - Abstract: Arsenic trioxide (As 2 O 3 ) has shown therapeutic effects in some leukemias and solid cancers. However, the molecular mechanisms of its anticancer efficacy have not been clearly elucidated, particularly in solid cancers. Our previous data showed that As 2 O 3 induced apoptosis of human papillomavirus (HPV) 16 DNA-immortalized human cervical epithelial cells and cervical cancer cells and inhibited the expression of HPV oncogenes in these cells. In the present study, we systemically examined the effects of As 2 O 3 on five human cervical cancer cell lines and explored the possible molecular mechanisms. MTT assay showed that HPV-negative C33A cells were more sensitive to growth inhibition induced by As 2 O 3 than HPV-positive cervical cancer cells, and HPV 18-positive HeLa and C4-I cells were more sensitive to As 2 O 3 than HPV 16-positive CaSki and SiHa cells. After As 2 O 3 treatment, both mRNA and protein levels of HPV E6 and E7 obviously decreased in all HPV positive cell lines. In contrast, p53 and Rb protein levels increased in all tested cell lines. Transcription factor AP-1 protein expression decreased significantly in HeLa, CaSki and C33A cells with ELISA method. These results suggest that As 2 O 3 is a potential anticancer drug for cervical cancer

Arsenic trioxide inhibits cell proliferation and human papillomavirus oncogene expression in cervical cancer cells

Energy Technology Data Exchange (ETDEWEB)

Wang, Hongtao [Department of Pathology, School of Medicine, Southeast University, Nanjing 210009 (China); Gao, Peng [Department of Internal Medicine, University of Iowa, Iowa City, IA 52242 (United States); Zheng, Jie, E-mail: jiezheng54@126.com [Department of Pathology, School of Medicine, Southeast University, Nanjing 210009 (China)

2014-09-05

Highlights: • As{sub 2}O{sub 3} inhibits growth of cervical cancer cells and expression of HPV oncogenes in these cells. • HPV-negative cervical cancer cells are more sensitive to As{sub 2}O{sub 3} than HPV-positive cervical cancer cells. • HPV-18 positive cervical cancer cells are more sensitive to As{sub 2}O{sub 3} than HPV-16 positive cancer cells. • Down-regulation of HPV oncogenes by As{sub 2}O{sub 3} is partially due to the diminished AP-1 binding. - Abstract: Arsenic trioxide (As{sub 2}O{sub 3}) has shown therapeutic effects in some leukemias and solid cancers. However, the molecular mechanisms of its anticancer efficacy have not been clearly elucidated, particularly in solid cancers. Our previous data showed that As{sub 2}O{sub 3} induced apoptosis of human papillomavirus (HPV) 16 DNA-immortalized human cervical epithelial cells and cervical cancer cells and inhibited the expression of HPV oncogenes in these cells. In the present study, we systemically examined the effects of As{sub 2}O{sub 3} on five human cervical cancer cell lines and explored the possible molecular mechanisms. MTT assay showed that HPV-negative C33A cells were more sensitive to growth inhibition induced by As{sub 2}O{sub 3} than HPV-positive cervical cancer cells, and HPV 18-positive HeLa and C4-I cells were more sensitive to As{sub 2}O{sub 3} than HPV 16-positive CaSki and SiHa cells. After As{sub 2}O{sub 3} treatment, both mRNA and protein levels of HPV E6 and E7 obviously decreased in all HPV positive cell lines. In contrast, p53 and Rb protein levels increased in all tested cell lines. Transcription factor AP-1 protein expression decreased significantly in HeLa, CaSki and C33A cells with ELISA method. These results suggest that As{sub 2}O{sub 3} is a potential anticancer drug for cervical cancer.

Presença do papilomavirus humano em lesões malignas de mucosa oral Presence of human papillomavirus in malignant oral lesions

Directory of Open Access Journals (Sweden)

Christiane Pienna Soares

2002-10-01

Full Text Available O objetivo deste estudo foi investigar a prevalência do papilomavírus humano 6/11 e 16/18 em pacientes, com lesões orais clínicamente diagnosticadas como leucoplasias, atendidas na Faculdade de Odontologia de Araraquara, UNESP, Brasil. Após a inclusão em parafina, os cortes corados com H&E, foram selecionadas 30 biópsias e separadas em 3 grupos: lesões sem displasia (n=10, lesões com diferentes graus de displasia (n=10 e carcinoma espinocelular invasivo(n=10. As lesões que apresentaram displasia epitelial foram classificadas de acordo com os critérios histopatológicos propostos por Van Der Waal. As lesões foram investigadas para a presença de HPV por hibridização in situ com sondas biotiniladas de amplo espectro, 6/11 e 16/18. HPV 16/18 foi detectado em 20% (n=2 das biópsias com displasia severa. A presença de HPV 16/18 em lesões malignas sugere sua importância como fator de risco na carcinogênese oral.The purpose of this study was to investigate the prevalence of human papillomavirus 6/11 and 16/18 in patients, with oral lesions clinically diagnosed as leucoplakia, attending the School of Dentistry, University of São Paulo State/UNESP, Brazil. After paraffin embedded process, in the sections staining with H&E, 30 biopsies were screened and separated on 3 groups: 10 oral lesions without dysplasia, 10 with dysplasia, and 10 with invasive squamous cell carcinoma. The lesions with dysplasia were classified in agreement with Van Der Wall's histopathological standard method. Oral lesions were investigated for the presence of human papillomavirus (HPV by in situ hybridization with wide-spectrum, 6/11 and 16/18 biotinylated probes. HPV 16/18 was found in 20% (n=2 of the leucoplakia with severe-degree dysplasia. The presence of HPV 16/18 in malignant lesions suggests its importance as a risk factor for oral carcinogenesis.

Immortalization of human foreskin keratinocytes by various human papillomavirus DNAs corresponds to their association with cervical carcinoma

Energy Technology Data Exchange (ETDEWEB)

Woodworth, C.D.; Doniger, J.; DiPaolo, J.A.

1989-01-01

Normal human foreskin keratinocytes cotransfected with the neomycin resistance gene and recombinant human papillomavirus (HPV) DNAs (types 16, 18, 31, and 33) that have a high or moderate association with cervical malignancy acquired immortality and contained integrated and transcriptionally active viral genomes. Only transcripts from the intact E6 and E7 genes were detected in at least one cell line, suggesting that one or both of these genes are responsible for immortalization. Recombinant HPV DNAs with low or no oncogenic potential for cervical cancer (HPV1a, -5, -6b, and -11) induced small G418-resistant colonies that senesced as did the nontransfected cells. These colonies contained only episomal virus DNA; therefore, integration of HPV sequences is important for immortalization of keratinocytes. This study suggests that the virus-encoded immortalization function contributes to the pathogenesis of cervical carcinoma.

Mouse papillomavirus infections spread to cutaneous sites with progression to malignancy.

Science.gov (United States)

Cladel, Nancy M; Budgeon, Lynn R; Cooper, Timothy K; Balogh, Karla K; Christensen, Neil D; Myers, Roland; Majerciak, Vladimir; Gotte, Deanna; Zheng, Zhi-Ming; Hu, Jiafen

2017-09-25

We report secondary cutaneous infections in the mouse papillomavirus (MmuPV1)/mouse model. Our previous study demonstrated that cutaneous MmuPV1 infection could spread to mucosal sites. Recently, we observed that mucosal infections could also spread to various cutaneous sites including the back, tail, muzzle and mammary tissues. The secondary site lesions were positive for viral DNA, viral capsid protein and viral particles as determined by in situ hybridization, immunohistochemistry and transmission electron microscopy analyses, respectively. We also demonstrated differential viral production and tumour growth at different secondarily infected skin sites. For example, fewer viral particles were detected in the least susceptible back tissues when compared with those in the infected muzzle and tail, although similar amounts of viral DNA were detected. Follow-up studies demonstrated that significantly lower amounts of viral DNA were packaged in the back lesions. Lavages harvested from the oral cavity and lower genital tracts were equally infectious at both cutaneous and mucosal sites, supporting the broad tissue tropism of this papillomavirus. Importantly, two secondary skin lesions on the forearms of two mice displayed a malignant phenotype at about 9.5 months post-primary infection. Therefore, MmuPV1 induces not only dysplasia at mucosal sites such as the vagina, anus and oral cavity but also skin carcinoma at cutaneous sites. These findings demonstrate that MmuPV1 mucosal infection can be spread to cutaneous sites and suggest that the model could serve a useful role in the study of the viral life cycle and pathogenesis of papillomavirus.

Clinical trial experience with prophylactic human papillomavirus 6/11/16/18 vaccine in young black women.

Science.gov (United States)

Clark, Liana R; Myers, Evan R; Huh, Warner; Joura, Elmar A; Paavonen, Jorma; Perez, Gonzalo; James, Margaret K; Sings, Heather L; Haupt, Richard M; Saah, Alfred J; Garner, Elizabeth I O

2013-03-01

Human papillomavirus (HPV) is the causative agent of cervical cancer. Black women are disproportionally diagnosed and have higher mortality from cervical cancer in the United States. Here we describe the prophylactic efficacy and safety of a quadrivalent HPV-6/11/16/18 vaccine in black women. A total of 700 black women from Latin America, Europe, and North America (aged 16-24 years) received the vaccine or placebo in one of two studies. Analyses focused on the efficacy and safety of the vaccine. Baseline rates of Chlamydia trachomatis infection and history of past pregnancy were more than twice as high in black women compared with the non-black women who were enrolled in these trials. HPV-6/11/16 or 18 DNA was detected in 18% of black women versus 14.6% in non-black women at day 1. For black women, vaccine efficacy against disease caused by HPV-6/11/16/18 was 100% for cervical intraepithelial neoplasia (0 vs. 15 cases; 95% confidence interval, 64.5%-100%) and 100% for vulvar and vaginal intraepithelial neoplasia and condylomata acuminata (0 vs. 17 cases; 95% confidence interval, 69.3%-100%). There were no serious vaccine-related adverse experiences. A similar proportion of pregnancies resulted in live births (75.8% vaccine; 72.7% placebo) and fetal loss (24.2% vaccine; 27.3% placebo). Prophylactic quadrivalent HPV-6/11/16/18 vaccination of young black women demonstrated high efficacy, safety, and tolerability. HPV vaccination has the potential to reduce cervical cancer-related health disparities both in the United States and around the world. Copyright © 2013 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

Global challenges of implementing human papillomavirus vaccines

Directory of Open Access Journals (Sweden)

Mishra Amrita

2011-06-01

Full Text Available Abstract Human Papillomavirus vaccines are widely hailed as a sweeping pharmaceutical innovation for the universal benefit of all women. The implementation of the vaccines, however, is far from universal or equitable. Socio-economically marginalized women in emerging and developing, and many advanced economies alike, suffer a disproportionately large burden of cervical cancer. Despite the marketing of Human Papillomavirus vaccines as the solution to cervical cancer, the market authorization (licensing of the vaccines has not translated into universal equitable access. Vaccine implementation for vulnerable girls and women faces multiple barriers that include high vaccine costs, inadequate delivery infrastructure, and lack of community engagement to generate awareness about cervical cancer and early screening tools. For Human Papillomavirus vaccines to work as a public health solution, the quality-assured delivery of cheaper vaccines must be integrated with strengthened capacity for community-based health education and screening.

Disruption of genes encoding eIF4E binding proteins-1 and -2 does not alter basal or sepsis-induced changes in skeletal muscle protein synthesis in male or female mice.

Science.gov (United States)

Steiner, Jennifer L; Pruznak, Anne M; Deiter, Gina; Navaratnarajah, Maithili; Kutzler, Lydia; Kimball, Scot R; Lang, Charles H

2014-01-01

Sepsis decreases skeletal muscle protein synthesis in part by impairing mTOR activity and the subsequent phosphorylation of 4E-BP1 and S6K1 thereby controlling translation initiation; however, the relative importance of changes in these two downstream substrates is unknown. The role of 4E-BP1 (and -BP2) in regulating muscle protein synthesis was assessed in wild-type (WT) and 4E-BP1/BP2 double knockout (DKO) male mice under basal conditions and in response to sepsis. At 12 months of age, body weight, lean body mass and energy expenditure did not differ between WT and DKO mice. Moreover, in vivo rates of protein synthesis in gastrocnemius, heart and liver did not differ between DKO and WT mice. Sepsis decreased skeletal muscle protein synthesis and S6K1 phosphorylation in WT and DKO male mice to a similar extent. Sepsis only decreased 4E-BP1 phosphorylation in WT mice as no 4E-BP1/BP2 protein was detected in muscle from DKO mice. Sepsis decreased the binding of eIF4G to eIF4E in WT mice; however, eIF4E•eIF4G binding was not altered in DKO mice under either basal or septic conditions. A comparable sepsis-induced increase in eIF4B phosphorylation was seen in both WT and DKO mice. eEF2 phosphorylation was similarly increased in muscle from WT septic mice and both control and septic DKO mice, compared to WT control values. The sepsis-induced increase in muscle MuRF1 and atrogin-1 (markers of proteolysis) as well as TNFα and IL-6 (inflammatory cytokines) mRNA was greater in DKO than WT mice. The sepsis-induced decrease in myocardial and hepatic protein synthesis did not differ between WT and DKO mice. These data suggest overall basal protein balance and synthesis is maintained in muscle of mice lacking both 4E-BP1/BP2 and that sepsis-induced changes in mTOR signaling may be mediated by a down-stream mechanism independent of 4E-BP1 phosphorylation and eIF4E•eIF4G binding.

Preventing human papillomavirus-related cancers: we are all in this together.

Science.gov (United States)

Dilley, Sarah; Scarinci, Isabel; Kimberlin, David; Straughn, J Michael

2017-06-01

Human papillomavirus-related cancers, which include cervical, vulvovaginal, anal, and oropharyngeal cancers, are on the rise in the United States. Although the human papillomavirus vaccine has been on the market for 10 years, human papillomavirus vaccination rates are well below national goals. Research identified many barriers and facilitators to human papillomavirus vaccination, and provider recommendation remains the most important factor in parental and patient decisions to vaccinate. While much of the burden of human papillomavirus vaccine provision falls on pediatricians and primary care providers, they cannot do it alone. As clinicians who care for a large proportion of human papillomavirus-related conditions, obstetrician-gynecologists and other women's health care providers must share the responsibility for vaccination of eligible patients. Obstetrician-gynecologists can support the efforts to eradicate human papillomavirus-related disease in their patients and their families via multiple avenues, including providing the human papillomavirus vaccine and being community leaders in support of vaccination. Copyright © 2017 Elsevier Inc. All rights reserved.

Control of eIF4E cellular localization by eIF4E-binding proteins, 4E-BPs

OpenAIRE

Rong, Liwei; Livingstone, Mark; Sukarieh, Rami; Petroulakis, Emmanuel; Gingras, Anne-Claude; Crosby, Katherine; Smith, Bradley; Polakiewicz, Roberto D.; Pelletier, Jerry; Ferraiuolo, Maria A.; Sonenberg, Nahum

2008-01-01

Eukaryotic initiation factor (eIF) 4E, the mRNA 5′-cap-binding protein, mediates the association of eIF4F with the mRNA 5′-cap structure to stimulate cap-dependent translation initiation in the cytoplasm. The assembly of eIF4E into the eIF4F complex is negatively regulated through a family of repressor proteins, called the eIF4E-binding proteins (4E-BPs). eIF4E is also present in the nucleus, where it is thought to stimulate nuclear-cytoplasmic transport of certain mRNAs. eIF4E is transported...

Langerhans cell homeostasis and activation is altered in hyperplastic human papillomavirus type 16 E7 expressing epidermis.

Directory of Open Access Journals (Sweden)

Nor Malia Abd Warif

Full Text Available It has previously been shown that expression of human papillomavirus type 16 (HPV E7 in epidermis causes hyperplasia and chronic inflammation, characteristics of pre-malignant lesions. Importantly, E7-expressing epidermis is strongly immune suppressed and is not rejected when transplanted onto immune competent mice. Professional antigen presenting cells are considered essential for initiation of the adaptive immune response that results in graft rejection. Langerhans cells (LC are the only antigen presenting cells located in normal epidermis and altered phenotype and function of these cells may contribute to the immune suppressive microenvironment. Here, we show that LC are atypically activated as a direct result of E7 expression in the epidermis, and independent of the presence of lymphocytes. The number of LC was significantly increased and the LC are functionally impaired, both in migration and in antigen uptake. However when the LC were extracted from K14E7 skin and matured in vitro they were functionally competent to present and cross-present antigen, and to activate T cells. The ability of the LC to present and cross-present antigen following maturation supports retention of full functional capacity when removed from the hyperplastic skin microenvironment. As such, opportunities are afforded for the development of therapies to restore normal LC function in hyperplastic skin.