scholarly journals The E8 Domain Confers a Novel Long-Distance Transcriptional Repression Activity on the E8^E2C Protein of High-Risk Human Papillomavirus Type 31

2001 ◽  
Vol 75 (9) ◽  
pp. 4139-4149 ◽  
Author(s):  
Frank Stubenrauch ◽  
Thomas Zobel ◽  
Thomas Iftner
Keyword(s):  
Dna Replication ◽  
High Risk ◽  
Transcriptional Repression ◽  
Viral Gene Expression ◽  
Hpv Infection ◽  
Human Papillomaviruses ◽  
Viral Gene ◽  
Regulation Of Transcription ◽  
Long Distance ◽  
High Risk Hpv

ABSTRACT Infections with high-risk human papillomaviruses (HPVs) are the major risk factor for the development of anogenital cancers. Viral E2 proteins are involved in viral DNA replication and regulation of transcription. Repression of the viral P97 promoter by E2 proteins has been implicated in the modulation of the immortalization capacity and DNA replication properties of high-risk HPVs. Analysis of thecis and trans requirements for repression of the HPV type 31 (HPV31) P97 promoter, however, revealed striking differences between the full-length E2 and the E8^E2C fusion protein which were due to conserved residues W6 and K7 of the E8 domain. In contrast to E2, E8^E2C completely inhibited the P97 promoter from a single promoter-distal E2 binding site. This novel long-distance repression activity of the E8 domain also enabled E8^E2C to inhibit the HPV6a P2 promoter and minimal-promoter constructs containing E2 binding sites. Thus, E8^E2C may represent the master repressor of viral gene expression during a high-risk HPV infection, and changes in the activity of E8^E2C might contribute to the progression of high-risk HPV-induced lesions.

scholarly journals HPV and Other Microbiota; Who’s Good and Who’s Bad: Effects of the Microbial Environment on the Development of Cervical Cancer—A Non-Systematic Review

Cells ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 714
Author(s):  
Matthias Läsche ◽  
Horst Urban ◽  
Julia Gallwas ◽  
Carsten Gründker
Keyword(s):  
Systematic Review ◽  
Cervical Cancer ◽  
High Risk ◽  
Cervical Carcinoma ◽  
Hpv Infection ◽  
Human Papillomaviruses ◽  
Inflammatory Reactions ◽  
Metabolic Signalling ◽  
Microbial Environment ◽  
High Risk Hpv

Cervical cancer is responsible for around 5% of all human cancers worldwide. It develops almost exclusively from an unsolved, persistent infection of the squamocolumnar transformation zone between the endo- and ecto-cervix with various high-risk (HR) human papillomaviruses (HPVs). The decisive turning point on the way to persistent HPV infection and malignant transformation is an immune system weakened by pathobionts and oxidative stress and an injury to the cervical mucosa, often caused by sexual activities. Through these injury and healing processes, HPV viruses, hijacking activated keratinocytes, move into the basal layers of the cervical epithelium and then continue their development towards the distal prickle cell layer (Stratum spinosum). The microbial microenvironment of the cervical tissue determines the tissue homeostasis and the integrity of the protective mucous layer through the maintenance of a healthy immune and metabolic signalling. Pathological microorganisms and the resulting dysbiosis disturb this signalling. Thus, pathological inflammatory reactions occur, which manifest the HPV infection. About 90% of all women contract an HPV infection in the course of their lives. In about 10% of cases, the virus persists and cervical intra-epithelial neoplasia (CIN) develops. Approximately 1% of women with a high-risk HPV infection incur a cervical carcinoma after 10 to 20 years. In this non-systematic review article, we summarise how the sexually and microbial mediated pathogenesis of the cervix proceeds through aberrant immune and metabolism signalling via CIN to cervical carcinoma. We show how both the virus and the cancer benefit from the same changes in the immune and metabolic environment.

scholarly journals CCCTC-Binding Factor Recruitment to the Early Region of the Human Papillomavirus 18 Genome Regulates Viral Oncogene Expression

2015 ◽  
Vol 89 (9) ◽  
pp. 4770-4785 ◽  
Author(s):  
Christian Paris ◽  
Ieisha Pentland ◽  
Ian Groves ◽  
David C. Roberts ◽  
Simon J. Powis ◽  
...  
Keyword(s):  
Gene Expression ◽  
High Risk ◽  
Host Cell ◽  
Viral Gene Expression ◽  
Early Gene ◽  
Ctcf Binding ◽  
Ctcf Binding Site ◽  
Viral Gene ◽  
Genome Wide ◽  
High Risk Hpv

ABSTRACTHost cell differentiation-dependent regulation of human papillomavirus (HPV) gene expression is required for productive infection. The host cell CCCTC-binding factor (CTCF) functions in genome-wide chromatin organization and gene regulation. We have identified a conserved CTCF binding site in the E2 open reading frame of high-risk HPV types. Using organotypic raft cultures of primary human keratinocytes containing high-risk HPV18 genomes, we show that CTCF recruitment to this conserved site regulates viral gene expression in differentiating epithelia. Mutation of the CTCF binding site increases the expression of the viral oncoproteins E6 and E7 and promotes host cell proliferation. Loss of CTCF binding results in a reduction of a specific alternatively spliced transcript expressed from the early gene region concomitant with an increase in the abundance of unspliced early transcripts. We conclude that high-risk HPV types have evolved to recruit CTCF to the early gene region to control the balance and complexity of splicing events that regulate viral oncoprotein expression.IMPORTANCEThe establishment and maintenance of HPV infection in undifferentiated basal cells of the squamous epithelia requires the activation of a subset of viral genes, termed early genes. The differentiation of infected cells initiates the expression of the late viral transcripts, allowing completion of the virus life cycle. This tightly controlled balance of differentiation-dependent viral gene expression allows the virus to stimulate cellular proliferation to support viral genome replication with minimal activation of the host immune response, promoting virus productivity. Alternative splicing of viral mRNAs further increases the complexity of viral gene expression. In this study, we show that the essential host cell protein CTCF, which functions in genome-wide chromatin organization and gene regulation, is recruited to the HPV genome and plays an essential role in the regulation of early viral gene expression and transcript processing. These data highlight a novel virus-host interaction important for HPV pathogenicity.

scholarly journals Detection Rates of Human Papillomavirus Associated with Cervical Cancer in Women of Nizhny Novgorod

2020 ◽  
pp. 44-47
Author(s):  
NF Brusnigina ◽  
MA Makhova ◽  
OM Chernevskaya ◽  
KA Orlova ◽  
EA Kolesnikova ◽  
...  
Keyword(s):  
Cervical Cancer ◽  
Human Papillomavirus ◽  
High Risk ◽  
Hpv Infection ◽  
Human Papillomaviruses ◽  
Hpv 16 ◽  
Detection Rates ◽  
High Risk Hpv ◽  
Incident Cases ◽  
Oncogenic Hpv

The purpose of the study was to assess detection rates of human papillomavirus in cervical cancer cases of Nizhny Novgorod. Materials and methods. We used the real-time polymerase chain reaction (PCR) to test samples of mucosa lining of the cervical canal and/or transformation zone taken from 630 women with cervical dysplasia of different degrees and 107 incident cases of cervical cancer that did not undergo treatment. The detection and differentiation of 14 genotypes of high-risk human papillomaviruses (HPV) was carried out using the AmpliSens® HPV HCR-genotype-FRT PRC kit. Results. The overall infection rate of women with oncogenic human papillomaviruses was 41.8%. Among the genotypes, HPV 16 (39.2%), 18 (15.5%), 33 (16.6%), and 56 (11.9%) predominated. A high prevalence of oncogenic HPV was detected in the women with cervical intraepithelial neoplasia (58.1%) and cervical cancer (90%). The spectrum of genotypes in women with neoplasia of various degrees differed. In women with CIN II and CIN III, vaccine-preventable HPV genotypes (HPV 16 and 18) playing the leading role in the development of cervical cancer were the most frequent. The same genotypes dominated in the women with invasive cervical cancer. One oncogenic HPV genotype was usually found in the infected women (69%). The high-risk HPV infection was often combined with Ureaplasma ssp (49.3%), Mycoplasma hominis (20.1%), Cytomegalovirus (21.1%), and Herpes simplex I/II (18.2%) infections. Combinations of high-risk HPV with Chlamydia trachomatis and Herpes 6 were found in 8.3% and 5% of the cases, respectively. Conclusions. Our findings proved a wide prevalence of high carcinogenic risk HPV 16 and 18 genotypes, thus indicating the expediency of using Cervarix and Gardasil vaccines registered in the Russian Federation and containing antigens to these types of virus for specific prevention of the HPV infection.

scholarly journals The Laboratory Diagnosis of Genital Human Papillomavirus Infections

2005 ◽  
Vol 16 (2) ◽  
pp. 83-91 ◽  
Author(s):  
François Coutlee ◽  
Danielle Rouleau ◽  
Alex Ferenczy ◽  
Eduardo Franco
Keyword(s):  
Cervical Cancer ◽  
High Risk ◽  
Hpv Infection ◽  
Human Papillomaviruses ◽  
High Grade ◽  
Hpv Testing ◽  
Screening Programs ◽  
Detection Techniques ◽  
Hpv Types ◽  
High Risk Hpv

Human papillomaviruses (HPVs) are the etiological agents of several genital cancers, including cancer of the uterine cervix. The detection of HPV infection in genital samples may increase the sensitivity of primary and secondary screenings of cervical cancer. HPV testing may also improve the specificity of screening programs, resulting in the avoidance of overtreatment and cost savings for confirmatory procedures. The major determinants of clinical progression of HPV infection include persistence of HPV infection, involvement of high-risk HPV types, high HPV viral load, integration of viral DNA and presence of several potential cofactors. Signal amplification HPV-DNA detection techniques (Hybrid Capture II, Digene Corporation, USA) are standardized, commercially available, and capable of detecting several high-risk HPV types. They also increase the sensitivity of screening for high-grade lesions in combination with cytology. The sensitivity of these techniques to detect high-grade lesions is higher than that of cytology, but the referral rate for colposcopy is greater. These techniques are approved for the triage to colposcopy of women with cervical smears interpreted as atypical squamous cells of undetermined significance. Triage and screening for cervical cancer using HPV will probably be restricted to women aged 30 years or older because of the high prevalence of infection in younger women. Amplification techniques are ideal for epidemiological studies because they minimize the misclassification of HPV infection status. These techniques can detect low HPV burden infections. Consensus primers amplify most genital types in one reaction, and the reverse hybridization of amplicons with type-specific probes allows for the typing of HPV-positive samples. Consensus PCR assays are currently under evaluation for diagnostic purposes. HPV testing is currently implemented for the clinical management of women.

scholarly journals Alleviation of Human Papillomavirus E2-Mediated Transcriptional Repression via Formation of a TATA Binding Protein (or TFIID)-TFIIB-RNA Polymerase II-TFIIF Preinitiation Complex

2000 ◽  
Vol 20 (1) ◽  
pp. 113-125 ◽  
Author(s):  
Samuel Y. Hou ◽  
Shwu-Yuan Wu ◽  
Tianyuan Zhou ◽  
Mary C. Thomas ◽  
Cheng-Ming Chiang
Keyword(s):  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Transcriptional Repression ◽  
Binding Protein ◽  
Viral Gene Expression ◽  
Tata Binding Protein ◽  
Human Papillomaviruses ◽  
Viral Gene ◽  
Preinitiation Complex ◽  
Hpv E6

ABSTRACT Transcription in human papillomaviruses (HPVs) is mainly regulated by cellular transcription factors and virus-encoded E2 proteins that act as sequence-specific DNA-binding proteins. Although the functions of E2 as a transcriptional activator and a repressor have been well documented, the role of cellular factors involved in E2-mediated regulation of the HPV promoters and the mechanism by which E2 modulates viral gene expression remain unclear. Using reconstituted cell-free transcription systems, we found that cellular enhancer-binding factors and general cofactors, such as TAFIIs, TFIIA, Mediator, and PC4, are not required for E2-mediated repression. Unlike other transcriptional repressors that function through recruitment of histone deacetylase or corepressor complexes, HPV E2 is able to directly target components of the general transcription machinery to exert its repressor activity on the natural HPV E6 promoter. Interestingly, preincubation of TATA binding protein (TBP) or TFIID with HPV template is not sufficient to overcome E2-mediated repression, which can be alleviated only via formation of a minimal TBP (or TFIID)-TFIIB-RNA polymerase II-TFIIF preinitiation complex. Our data therefore indicate that E2 does not simply work by displacing TBP or TFIID from binding to the adjacent TATA box. Instead, E2 appears to function as an active repressor that directly inhibits HPV transcription at steps after TATA recognition by TBP or TFIID.

scholarly journals Human Papillomavirus Type 31b Infection of Human Keratinocytes Does Not Require Heparan Sulfate

2005 ◽  
Vol 79 (11) ◽  
pp. 6838-6847 ◽  
Author(s):  
Nicole A. Patterson ◽  
Jessica L. Smith ◽  
Michelle A. Ozbun
Keyword(s):  
High Risk ◽  
Heparan Sulfate ◽  
Human Keratinocytes ◽  
Hpv Infection ◽  
Infection Process ◽  
Human Papillomaviruses ◽  
Viral Attachment ◽  
Successful Infection ◽  
High Risk Hpv

ABSTRACT Oncogenic human papillomaviruses (HPVs) are difficult to study experimentally as they replicate at low levels in vivo. This has precluded the purification of high-risk HPV virions from in vivo lesions. Virus-like particles (VLPs) and pseudovirions from low- and high-risk HPV types can emulate various aspects of HPV virion attachment and infections. These studies suggest that HPV infection is mediated by α6-integrin and/or heparan-sulfonated receptors. However, whether VLPs and pseudovirions accurately reflect the infection process of HPV virions has not been verified. We generated infectious HPV31b virions from organotypic (raft) tissues and performed experimental infections in a variety of cells. Successful infection following viral attachment, internalization, and nuclear transport was assayed by detecting newly synthesized, spliced HPV transcripts using reverse transcription (RT)-PCR or RT-quantitative PCR. Most human epithelial cells were infected with HPV31b at a multiplicity of infection as low as 1 to 10 viral genome equivalents per cell. HPV31b infection was detected in other cell lines, including COS-7 monkey kidney cells, but higher viral multiplicities of infection were required. Heparin preparations of various molecular weights or heparinase I treatment of cells prevented HPV31b infection of COS-7 cells and C-33A human cervical cancer cells in reproducible and dose-dependent manners. However, these reagents were unable to block infection of human keratinocytes, including HaCaT and N/TERT-1 cells and low-passage human foreskin keratinocytes. These data suggest that HPV31b infection of human keratinocytes, the natural host cell for HPV infections in vivo, does not require a heparan-sulfonated receptor, whereas heparan sulfate is important for infection of some other cells.

Molecular biology of human papillomavirus infection and cervical cancer

2006 ◽  
Vol 110 (5) ◽  
pp. 525-541 ◽  
Author(s):  
John Doorbar
Keyword(s):  
Gene Expression ◽  
High Risk ◽  
Viral Gene Expression ◽  
Cervical Neoplasia ◽  
Productive Infection ◽  
Viral Gene ◽  
Low Grade ◽  
Cervical Cancers ◽  
Hpv Types ◽  
High Risk Hpv

HPVs (human papillomaviruses) infect epithelial cells and cause a variety of lesions ranging from common warts/verrucas to cervical neoplasia and cancer. Over 100 different HPV types have been identified so far, with a subset of these being classified as high risk. High-risk HPV DNA is found in almost all cervical cancers (>99.7%), with HPV16 being the most prevalent type in both low-grade disease and cervical neoplasia. Productive infection by high-risk HPV types is manifest as cervical flat warts or condyloma that shed infectious virions from their surface. Viral genomes are maintained as episomes in the basal layer, with viral gene expression being tightly controlled as the infected cells move towards the epithelial surface. The pattern of viral gene expression in low-grade cervical lesions resembles that seen in productive warts caused by other HPV types. High-grade neoplasia represents an abortive infection in which viral gene expression becomes deregulated, and the normal life cycle of the virus cannot be completed. Most cervical cancers arise within the cervical transformation zone at the squamous/columnar junction, and it has been suggested that this is a site where productive infection may be inefficiently supported. The high-risk E6 and E7 proteins drive cell proliferation through their association with PDZ domain proteins and Rb (retinoblastoma), and contribute to neoplastic progression, whereas E6-mediated p53 degradation prevents the normal repair of chance mutations in the cellular genome. Cancers usually arise in individuals who fail to resolve their infection and who retain oncogene expression for years or decades. In most individuals, immune regression eventually leads to clearance of the virus, or to its maintenance in a latent or asymptomatic state in the basal cells.

scholarly journals Genotype distribution characteristics of high-risk human papillomaviruses in women from Shanghai, China

2015 ◽  
Vol 144 (7) ◽  
pp. 1482-1489 ◽  
Author(s):  
Y. GU ◽  
M. YI ◽  
Y. XU ◽  
H. ZHAO ◽  
F. FU ◽  
...  
Keyword(s):  
High Risk ◽  
Vaccination Strategy ◽  
Hpv Infection ◽  
Human Papillomaviruses ◽  
Low Risk ◽  
Multiple Infection ◽  
Genotype Distribution ◽  
Infection Rates ◽  
Control And Prevention ◽  
High Risk Hpv

SUMMARYHigh-risk human papillomaviruses (HPVs) are highly prevalent worldwide, and HPV genotype distribution varies regionally. Molecular surveys of HPVs are important for effective HPV control and prevention. Fifteen high-risk HPV strains (16, 18, 31, 33, 35, 39, 45, 51, 52, 53, 56, 58, 59, 66, 68) and six low-risk HPV strains (HPV6, 11, 42, 43, 44, CP8304) were detected by cervical cytology from 10 501 subjects. High-risk HPVs, low-risk HPVs, and both high- and low-risk HPVs were detected in 14·5%, 2·8%, and 2·4% of cases, respectively. Of 1782 subjects with high-risk HPV infection, 75·5%, 18·1%, and 6·4% were infected with one, two, and ⩾3 strains of high-risk HPVs, respectively. HPV52, HPV16, and HPV58 were the top three most dominant high-risk HPV genotypes in our population with positivity rates of 23·0%, 17·7% and 16·9%, respectively. Multiple infection was common, with significantly higher co-infection rates of HPV58/HPV33 (12·9%) and HPV58/HPV52 (11·3%). Further data comparisons showed that HPV genotype distribution varied markedly between domestic and international regions. In conclusion, a monolithic vaccination strategy is obviously impractical, and regional HPV surveillance is essential to optimize current HPV control and prevention.

scholarly journals The human papillomavirus replication cycle, and its links to cancer progression: a comprehensive review

2017 ◽  
Vol 131 (17) ◽  
pp. 2201-2221 ◽  
Author(s):  
Sheila V. Graham
Keyword(s):  
Epithelial Cells ◽  
Cancer Progression ◽  
Viral Gene Expression ◽  
Hpv Infection ◽  
Human Papillomaviruses ◽  
Replication Cycle ◽  
Productive Infection ◽  
Keratinocyte Differentiation ◽  
Viral Gene ◽  
Cervical Disease

HPVs (human papillomaviruses) infect epithelial cells and their replication cycle is intimately linked to epithelial differentiation. There are over 200 different HPV genotypes identified to date and each displays a strict tissue specificity for infection. HPV infection can result in a range of benign lesions, for example verrucas on the feet, common warts on the hands, or genital warts. HPV infects dividing basal epithelial cells where its dsDNA episomal genome enters the nuclei. Upon basal cell division, an infected daughter cell begins the process of keratinocyte differentiation that triggers a tightly orchestrated pattern of viral gene expression to accomplish a productive infection. A subset of mucosal-infective HPVs, the so-called ‘high risk’ (HR) HPVs, cause cervical disease, categorized as low or high grade. Most individuals will experience transient HR-HPV infection during their lifetime but these infections will not progress to clinically significant cervical disease or cancer because the immune system eventually recognizes and clears the virus. Cancer progression is due to persistent infection with an HR-HPV. HR-HPV infection is the cause of >99.7% cervical cancers in women, and a subset of oropharyngeal cancers, predominantly in men. HPV16 (HR-HPV genotype 16) is the most prevalent worldwide and the major cause of HPV-associated cancers. At the molecular level, cancer progression is due to increased expression of the viral oncoproteins E6 and E7, which activate the cell cycle, inhibit apoptosis, and allow accumulation of DNA damage. This review aims to describe the productive life cycle of HPV and discuss the roles of the viral proteins in HPV replication. Routes to viral persistence and cancer progression are also discussed.

Comparison of Co-Presence of Epstein-Barr Virus and High-Risk Human Papillomaviruses in Colorectal Cancers in the Middle East Region

2020 ◽  
Author(s):  
Karim Nagi ◽  
Ishita Gupta ◽  
Hamda A Al-Thawadi ◽  
Ayesha Jabeen ◽  
Mohammed I. Malk ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
High Risk ◽  
Epstein Barr Virus ◽  
Human Papillomaviruses ◽  
Colorectal Cancers ◽  
Barr Virus ◽  
Human Carcinomas ◽  
Epstein Barr ◽  
Invasive Carcinomas ◽  
High Risk Hpv

Background: Several studies have shown the presence of onco viral DNA in colorectal tumor tissues. Viral infection by onco-viruses such as Human papillomaviruses (HPVs) and Epstein–Barr virus (EBV) are well-known to be involved in the onset and/or progression of numerous human carcinomas. Methods: We explored the co-presence of high-risk HPVs and EBV in a cohort of colorectal cancer samples from Lebanon (94) and Syria (102) by PCR, immunohistochemistry and tissue microarray. Results: The results of the study point out that 54% of colorectal cancer cases in Syria are positive for high-risk HPVs, while 30% of the cases in Lebanon are positive for these viruses; the most frequent high-risk HPV types in these populations are 16, 18, 31, 33 and 35. Analysis of LMP1 showed similar results in both populations; 36% of Syrian and 31% of Lebanese samples. Additionally, we report that EBV and high-risk HPVs are co-present in these samples. In Syrian samples, EBV and HPVs are co-present in 16% of the population, however, in the Lebanese samples, 20% of the cases are positive for both EBV and HPVs; their co-presence is associated with high/intermediate grade invasive carcinomas. Conclusion: These data suggest that EBV and high-risk HPVs are co-present in human colorectal cancers where they can cooperate in the progression of these cancers. Nevertheless, further studies are needed to elucidate the role of those oncoviruses in the development of human colorectal carcinomas.

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