High-risk HPVs play a causal role in the development of cervical cancer, and their E6 oncoproteins target h-Dlg for ubiquitin-mediated proteolysis. The h-Dlg oncosuppressor is associated with cell-cell interactions, and deregulation of these structures leads to defective cell adhesion, loss of cell polarity and unregulated proliferation. We evaluated the contribution of this E6 activity in the progression to malignancy in HPV infections by analyzing h-Dlg expression in HPV-associated lesions. We analyzed h-Dlg in cervical, laryngeal, vulvar, colon and kidney histologic samples by Dlg immunohistochemistry. HPV association was ascertained by a PCR-colorimetric method. Although Dlg was certainly expressed in intraepithelial cervical, vulvar and laryngeal HPVassociated lesions, its cellular and tissue distribution patterns were altered compared to normal tissue. However, marked reduction in Dlg levels was observed in HPV-positive invasive cervical carcinomas. To elucidate whether the loss of Dlg was significant for carcinogenesis in general, we investigated Dlg expression in tumors not associated with HPV. In colon and kidney carcinomas, Dlg was expressed, albeit with a different pattern of distribution with respect to the normal tissue. The loss of Dlg may be considered a late-stage marker in cervical carcinogenesis, but alterations in its expression and localization take place during the different dysplastic stages. Dlg downregulation and/or alterations in its localization may contribute to transformation and may explain some of the characteristics of the malignant cells, such as loss of polarity and high migration ability. © 2004 Wiley-Liss, Inc. Key words: human papillomavirus; E6 protein; hDlg oncosuppressor; proteolysis; immunohistochemistryA large number of epidemiologic studies have demonstrated high-risk HPV association in almost 100% of invasive carcinomas of the uterine cervix and in the development of precursor intraepithelial neoplastic lesions. 1 The principal oncogenic effects of HPVs are mediated by the E6 and E7 proteins, which target and interfere with the function of key regulatory cellular proteins. 2 E6 oncoproteins have a great number of cellular targets involved in the regulation of cell proliferation, differentiation, apoptosis and adhesion. E6 stimulates the degradation of many of its partners, such as p53, bak, Mcm7, h-Dlg1 and h-scrib, by ubiquitin-mediated proteolysis. [3][4][5][6][7] Dlg, human homologue of Drosophila Dlg-A, was the first reported target of E6 related to cell-cell interactions and polarity. 6 Dlg 8,9 is a member of the MAGuK family of proteins, characterized by specific protein recognition domains including SH3, PDZ and homologous GuK regions. 8 -10 In Drosophila, Dlg is involved in cell growth control, maintenance of cell adhesion and polarity and functions that block cell invasion during development. 11 Dlg and another 2 related tumor suppressors, scribble and lgl, act cooperatively in regulating cell polarity and proliferation, suggesting an important connection betw...
We explored the cutaneotropic HPV genetic diversity in 71 subjects from Argentina. New generic primers (CUT) targeting 88 mucosal/cutaneous HPV were designed and compared to FAP primers. Overall, 69 different HPV types/putative types were identified, being 17 of them novel putative types. Phylogenetic analysis of partial L1 sequences grouped 2 novel putative types in the Beta-PV, 14 in the Gamma-PV and 1 in the Mu-PV genera. CUT primers showed broader capacity than FAP primers in detecting different genera/species and novel putative types (p<0.01). Using overlapping PCR, the full-length genome of a Beta-PV putative type was amplified and cloned. The new virus, designated HPV 115, encodes 5 early genes and 2 late genes. Phylogenetic analysis indicated HPV 115 as the most divergent type within the genus Beta-PV species 3. This report is the first providing data on cutaneous HPVs circulating in South America and expands our knowledge of the Papillomaviridae family.
Human papillomavirus type 6 (HPV6) is the major etiological agent of anogenital warts and laryngeal papillomas and has been included in both the quadrivalent and nonavalent prophylactic HPV vaccines. This study investigated the global genomic diversity of HPV6, using 724 isolates and 190 complete genomes from six continents, and the association of HPV6 genomic variants with geographical location, anatomical site of infection/disease, and gender. Initially, a 2,800-bp E5a-E5b-L1-LCR fragment was sequenced from 492/530 (92.8%) HPV6-positive samples collected for this study. Among them, 130 exhibited at least one single nucleotide polymorphism (SNP), indel, or amino acid change in the E5a-E5b-L1-LCR fragment and were sequenced in full. A global alignment and maximum likelihood tree of 190 complete HPV6 genomes (130 fully sequenced in this study and 60 obtained from sequence repositories) revealed two variant lineages, A and B, and five B sublineages: B1, B2, B3, B4, and B5. HPV6 (sub)lineage-specific SNPs and a 960-bp representative region for whole-genome-based phylogenetic clustering within the L2 open reading frame were identified. Multivariate logistic regression analysis revealed that lineage B predominated globally. Sublineage B3 was more common in Africa and North and South America, and lineage A was more common in Asia. Sublineages B1 and B3 were associated with anogenital infections, indicating a potential lesion-specific predilection of some HPV6 sublineages. Females had higher odds for infection with sublineage B3 than males. In conclusion, a global HPV6 phylogenetic analysis revealed the existence of two variant lineages and five sublineages, showing some degree of ethnogeographic, gender, and/or disease predilection in their distribution. IMPORTANCEThis study established the largest database of globally circulating HPV6 genomic variants and contributed a total of 130 new, complete HPV6 genome sequences to available sequence repositories. Two HPV6 variant lineages and five sublineages were identified and showed some degree of association with geographical location, anatomical site of infection/disease, and/or gender. We additionally identified several HPV6 lineage-and sublineage-specific SNPs to facilitate the identification of HPV6 variants and determined a representative region within the L2 gene that is suitable for HPV6 whole-genome-based phylogenetic analysis. This study complements and significantly expands the current knowledge of HPV6 genetic diversity and forms a comprehensive basis for future epidemiological, evolutionary, functional, pathogenicity, vaccination, and molecular assay development studies.
More than 170 human papillomavirus (HPV) types have been completely sequenced, curated and divided into five genera: Alphapapillomavirus, Betapapillomavirus, Gammapapillomavirus, Mupapillomavirus and Nupapillomavirus. With the application of PCR methods, hundreds of putative novel HPV types have been identified as PCR amplicons in mucosa and skin. However, at present there are no studies reporting a systematic search of the currently known L1 amplicons and their phylogenetic relationships. This survey revealed the existence of at least 202 different putative HPV types that are pending for full-genome characterization: five alphapapillomaviruses, 37 betapapillomaviruses, 159 gammapapillomaviruses and one mupapillomavirus. All potential viruses of the genera Alphapapillomavirus and Betapapillomavirus were grouped in the defined species, while 59 putative gammapapillomaviruses types were segregated in 21 unidentified putative species. These data highlight the need for progress in the identification of additional taxa of the family Papillomaviridae in order to elucidate the diversity, evolution and medical implications of these viruses.Papillomaviruses (PVs) are small non-enveloped DNA tumour viruses with a circular genome of nearly 8 kb. PVs infect the epithelia of vertebrates and are host specific (Bernard et al., 2010). By convention, designation of a novel PV type requires the genome to be cloned and curated by the Papillomavirus Reference Center and show less than 90 % identity in the L1 ORF with respect to any known PV type, while PV types belonging to new species within a genus share 60-70 % nucleotide identity with PV types within this genus (de Villiers et al., 2004).Presently, 170 human PV (HPV) types have been officially designated and completely sequenced (de Villiers, 2013; http://www.hpvcenter.se/html/refclones.html), and divided into five genera according to their L1 ORF phylogenetic relationships: Alphapapillomavirus, Betapapillomavirus, Gammapapillomavirus, Mupapillomavirus and Nupapillomavirus. There is diversity in the pathology of the HPV types across the genera and species, in particular in relation to the epithelium infected and the oncogenic potential of the viral type. The genus Alphapapillomavirus is heterogeneous, containing: (i) the high-risk mucosal HPV types in species a-7 and a-9; (ii) low-risk mucocutaneous genital types in species a-10; and (iii) viruses grouped in the species a-4, which are most frequently associated with common skin warts (Bernard et al., 2010;de Villiers et al., 2004).Other HPV-containing genera are less heterogeneous. The betapapillomavirus (b-PV) types cause flat lesions in epidermodysplasia verruciformis patients, but evident HPV lesions are rare in immune-competent individuals (Pfister et al., 2003). The mupapillomavirus (m-PV) and some gammapapillomavirus (c-PV) types cause proliferative cutaneous lesions in humans, although the recently identified c-PV types are not associated with known lesions. In addition, c-PV and m-PV types differ from each other in that...
Bats provide important ecosystem services as pollinators, seed dispersers, and/or insect controllers, but they have also been found harboring different viruses with zoonotic potential. Virome studies in bats distributed in Asia, Africa, Europe, and North America have increased dramatically over the past decade, whereas information on viruses infecting South American species is scarce. We explored the virome of Tadarida brasiliensis, an insectivorous New World bat species inhabiting a maternity colony in Rosario (Argentina), by a metagenomic approach. The analysis of five pooled oral/anal swab samples indicated the presence of 43 different taxonomic viral families infecting a wide range of hosts. By conventional nucleic acid detection techniques and/or bioinformatics approaches, the genomes of two novel viruses were completely covered clustering into the Papillomaviridae (Tadarida brasiliensis papillomavirus type 1, TbraPV1) and Genomoviridae (Tadarida brasiliensis gemykibivirus 1, TbGkyV1) families. TbraPV1 is the first papillomavirus type identified in this host and the prototype of a novel genus. TbGkyV1 is the first genomovirus reported in New World bats and constitutes a new species within the genus Gemykibivirus. Our findings extend the knowledge about oral/anal viromes of a South American bat species and contribute to understand the evolution and genetic diversity of the novel characterized viruses.
This study developed a hanging-droplet long PCR, a generic and highly sensitive strategy to facilitate the identification of new human papillomavirus (HPV) genomes. This novel procedure used for the first time the hanging-droplet PCR technique for the amplification of long DNA fragments with generic primers targeting the L1 and E1 regions. It was first applied to the amplification of types belonging to the highly divergent genus Gammapapillovirus (c-PV). The hanging-droplet long PCR was 100-fold more sensitive than a simple long PCR procedure, detecting as few as ten copies of HPV-4. Nineteen skin samples, potentially containing putative HPV types from the c-PV genus, were also screened. The method identified four c-PV genomic halves from new and previously described putative types, and made the full characterization of HPV-156 possible. This novel virus meets the criteria for a new species within the c-PV genus, with nucleotide identities in the L1 ORF ranging from 58.3 to 67.3 % compared with representative types of the current c-PV species. HPV-156 showed the highest identity to HPV-60 (67.3 %) from species c-4, and was consistently closely related to it in both late-and earlygene-derived phylogenies. In conclusion, this report provides a versatile and highly sensitive approach that allowed identification of the prototype of a new species within the c-PV genus. Its application with primers targeting the different genera in which both human and non-human PVs are distributed may facilitate characterization of the missing members of the family Papillomaviridae.
SARS-CoV-2 variants with concerning characteristics have emerged since the end of 2020. Surveillance of SARS-CoV-2 variants was performed on a total of 4,851 samples from the capital city and 10 provinces of Argentina, during 51 epidemiological weeks (EWs) that covered the end of the first wave and the ongoing second wave of the COVID-19 pandemic in the country (EW 44/2020 to EW 41/2021). The surveillance strategy was mainly based on Sanger sequencing of a Spike coding region that allows the identification of signature mutations associated with variants. In addition, whole-genome sequences were obtained from 637 samples. The main variants found were Gamma and Lambda, and to a lesser extent, Alpha, Zeta, and Epsilon, and more recently, Delta. Whereas, Gamma dominated in different regions of the country, both Gamma and Lambda prevailed in the most populated area, the metropolitan region of Buenos Aires. The lineages that circulated on the first wave were replaced by emergent variants in a term of a few weeks. At the end of the ongoing second wave, Delta began to be detected, replacing Gamma and Lambda. This scenario is consistent with the Latin American variant landscape, so far characterized by a concurrent increase in Delta circulation and a stabilization in the number of cases. The cost-effective surveillance protocol presented here allowed for a rapid response in a resource-limited setting, added information on the expansion of Lambda in South America, and contributed to the implementation of public health measures to control the disease spread in Argentina.
Human papillomavirus 11 (HPV11) is an etiological agent of anogenital warts and laryngeal papillomas and is included in the 4-valent and 9-valent prophylactic HPV vaccines. We established the largest collection of globally circulating HPV11 isolates to date and examined the genomic diversity of 433 isolates and 78 complete genomes (CGs) from six continents. The genomic variation within the 2,800-bp E5a-E5b-L1-upstream regulatory region was initially studied in 181/207 (87.4%) HPV11 isolates collected for this study. Of these, the CGs of 30 HPV11 variants containing unique single nucleotide polymorphisms (SNPs), indels (insertions or deletions), or amino acid changes were fully sequenced. A maximum likelihood tree based on the global alignment of 78 HPV11 CGs (30 CGs from our study and 48 CGs from GenBank) revealed two HPV11 lineages (lineages A and B) and four sublineages (sublineages A1, A2, A3, and A4). HPV11 (sub)lineage-specific SNPs within the CG were identified, as well as the 208-bp representative region for CG-based phylogenetic clustering within the partial E2 open reading frame and noncoding region 2. Globally, sublineage A2 was the most prevalent, followed by sublineages A1, A3, and A4 and lineage B. IMPORTANCEThis collaborative international study defined the global heterogeneity of HPV11 and established the largest collection of globally circulating HPV11 genomic variants to date. Thirty novel complete HPV11 genomes were determined and submitted to the available sequence repositories. Global phylogenetic analysis revealed two HPV11 variant lineages and four sublineages. The HPV11 (sub)lineage-specific SNPs and the representative region identified within the partial genomic region E2/noncoding region 2 (NCR2) will enable the simpler identification and comparison of HPV11 variants worldwide. This study provides an important knowledge base for HPV11 for future studies in HPV epidemiology, evolution, pathogenicity, prevention, and molecular assay development. Human papillomavirus 11 (HPV11), which belongs to species 10 of the Alphapapillomavirus genus (Alpha-PV), is etiologically associated with approximately 20% of anogenital warts and 30 to 40% of laryngeal papillomas (1-11). HPV11 is generally considered a low-risk HPV type due to its rare presence in HPVrelated cancers in humans, especially cervical cancer (9). HPV11 is present in 0.5% of samples from HPV-positive women with a normal cytology worldwide and causes 2.3% of cervical low-grade squamous cell intraepithelial lesions (12, 13). However, rare case reports of HPV11-positive cases of cervical and anal squamous cell carcinomas, malignantly transformed laryngeal papillomas, and sinonasal inverted papillomas associated with squamous cell carcinoma can be found in the literature (14-21). Due to its clinical significance, HPV11 has been included in the current quadrivalent and nonavalent prophylactic HPV vaccines (22,23).The genetic diversity of HPV11 was studied for the first time in 1995, when Heinzel et al. sequenced the noncoding upstre...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.