Sublineage A1 Research Articles

Variant analysis of human papillomavirus type 52 in Iranian women during 2018-2020: A case-control study.

Knowing the regional variants of distinct human papillomavirus (HPV) types is valuable as it can be beneficial for studying their epidemiology, pathogenicity, and evolution. For this reason, the sequence variations of the E6 gene of HPV 52 were investigated among women with normal cervical cytology and premalignant/malignant cervical samples. Sixty-four HPV 52-positive samples were analyzed using semi-nested PCR and sequencing. Our findings showed that all samples belonged to lineage A (61%) or B (39%). Among samples that were infected with the A lineage, sublineages A1 and A2 were detected and sublineage A1 was dominant. No association was found between lineages and stage of disease (p > 0.05). Our results revealed that the A lineage, sublineage A1, and B lineage were common in Iranian women. Nevertheless, more studies with larger sample sizes are required to estimate the pathogenicity risk of HPV 52 lineages in Iranian women with cervical cancer.

Distribution of HPV types among women with HPV-related diseases and exploration of lineages and variants of HPV 52 and 58 among HPV-infected patients in China: A systematic literature review

ABSTRACT To summarize the distribution of types of human papillomavirus (HPV) associated with HPV-related diseases and investigate the potential causes of high prevalence of HPV 52 and 58 by summarizing the prevalence of lineages, sub-lineages, and mutations among Chinese women. We searched PubMed, EMBASE, CNKI, and WanFang from January, 2012 to June, 2023 to identify all the eligible studies. We excluded patients who had received HPV vaccinations. Data were summarized in tables and cloud/rain maps. A total of 102 studies reporting HPV distribution and 15 studies reporting HPV52/HPV58 variants were extracted. Among Chinese women, the top five prevalent HPV types associated with cervical cancer (CC) were HPV16, 18, 58, 52, and 33. In patients with vaginal cancers and precancerous lesions, the most common HPV types were 16 and 52 followed by 58. For women with condyloma acuminatum (CA), the most common HPV types were 11 and 6. In Chinese women with HPV infection, lineage B was the most prominently identified for HPV52, and lineage A was the most common for HPV58. In addition to HPV types 16, which is prevalent worldwide, our findings revealed the unique high prevalence of HPV 52/58 among Chinese women with HPV-related diseases. HPV 52 variants were predominantly biased toward lineage B and sub-lineage B2, and HPV 58 variants were strongly biased toward lineage A and sub-lineage A1. Further investigations on the association between the high prevalent lineage and sub-lineage in HPV 52/58 and the risk of cancer risk are needed. Our findings underscore the importance of vaccination with the nine-valent HPV vaccine in China.

HPV prevalence and genotype distribution among Vietnamese cervical cancer patients in the northern region of Vietnam, from 2018 – 2020

Background/purposeHPV infection is the primary cause of cervical cancer, and genotype distribution varies according to geographical location and carcinogenicity. Therefore, identifying HPV genotype and its association with cervical cancer features is critical for screening, diagnosis, and therapy. MethodsData from Vietnamese women with HPV-positive cervical cancer were collected from the northern region. The HPV genotype was identified using the Cobas®®4800 HPV system, whereas the nucleotide sequences of the E6, E7, and L1 genes were used to identify lineages and sublineages using DNASTAR, Bioedit, ATGC 7.2, and MEGA 11.0.10 softwares. ResultsOf the 180 patients infected with HPV, 82.8 % revealed single infections, and 17.2 % showed multiple infections. HPV16 (64.4 %), HPV18 (28.9 %), and other HPVs (6.7 %) were the most prevalent HPV genotypes. HPV16 lineages included European (sublineage A1 (11.2 %), A2 (1.72 %), and A3 (25.86 %); Asian (sublineage A4 (53.85 %); African-American (sublineage D1 (5.17 %); and Asian-American (sublineage D3 (2.59 %). The HPV18 lineage includes Asian-Ameridian (sublineages A1 (100 %)). HPV18 revealed a higher rate of cervical cancer, cervicitis, warts, and ulcers than HPV16 and other high-risk genotypes in the 35–54–year–old group, but did not show a difference in cancer stages. ConclusionsHPV16 and HPV18 genotypes are common in cervical cancer in northern Vietnam, with European, Asian, and Asian–Amerindian lineages predominating. HPV18 causes cervical cancer at a higher rate than other genotypes in the 35–54–year–old age group; thus, early identification of the genotype is critical for more successful therapy.

HPV16 Intratypic Variants in Head and Neck Cancers: A North American Perspective.

Human papillomavirus (HPV) is the major causative agent for cervical and many head and neck cancers (HNCs). HPVs randomly acquire single nucleotide polymorphisms (SNPs) that may become established via positive selection. Within an HPV type, viral isolates differing by <2% in the L1 region are termed "variants" and classified based on combinations of SNPs. Studies in cervical cancer demonstrate clear differences between HPV16 intratypic variants in terms of persistence of infection, tumor histology, cancer risk, and death. Much less is known about the frequency of HPV16 variants in HNC, and their effects on clinical outcomes. We combined HPV16 positive (HPV16+) HNC samples from a local Southwestern Ontario, Canada cohort with those from the Cancer Genome Atlas to create a larger North American cohort of 149 cases with clinical data and determined the distribution of intratypic variants and their impact on clinical outcomes. Most isolates were lineage A, sublineage A1, or A2, with roughly half exhibiting the T350G polymorphism in E6. Univariable analysis identified significant differences between 350T and 350G intratypic variants in clinical T, N, and O staging, as well as disease-free survival. Multivariable analysis failed to identify any clinical factor as a statistically significant covariate for disease-free survival differences between 350T and 350G. Significant differences in several measures of B-cell mediated immune response were also observed between 350T and 350G intratypic variants. We suggest that HPV genetic variation may be associated with HNC clinical characteristics and may have prognostic value.

Cervical carcinogenesis risk association of HPV33 E6 and E7 genetic variations in Taizhou, Southeast China

BackgroundHuman papillomavirus (HPV) 33 belongs to the Alphapapillomavirus 9 (α-9 HPV) species group, which also contains types 16, 31, 35, 52, 58 and 67. The purpose of this study was to investigate the genetic variations of HPV33 and to explore its carcinogenicity among women in Taizhou, Southeast China.MethodsExfoliated cervical cells were collected for HPV genotyping. Only single HPV33 infection cases were selected, and their E6 and E7 genes were sequenced using the ABI 3730xl sequencer and then analysed using MEGA X.ResultsFrom 2014 to 2020, a total of 185 single HPV33-positive specimens were successfully amplified. We obtained 15 distinct HPV33 E6/E7 variants, which were published in GenBank under accession numbers OQ672665-OQ672679. Phylogenetic analysis revealed that all HPV33 E6/E7 variants belonged to lineage A, of which 75.7% belonged to lineage A1. Compared with CIN1, the proportion of sublineage A1 in CIN2/3 was higher, but there was no significant difference (76.5% vs. 80.6%, P > 0.05). Altogether, 20 single nucleotide substitutions were identified, of which 6 were novel substitutions, including T196G (C30G), A447T, G458T (R117L), G531A, A704A, and C740T. In addition, no significant trends were observed between the nucleotide substitutions of HPV33 E6/E7 variants and the risk of cervical lesions.ConclusionThis study provides the most comprehensive data on genetic variations, phylogenetics and carcinogenicity of HPV33 E6/E7 variants in Southeast China to date. The data confirmed that cervical lesions among women in Taizhou are attributable to HPV33, which may be due to the high infection rate of sublineage A1 in the population.

Transcriptional activity of the long control region in human papillomavirus type 33 intratype variants

BackgroundHigh-risk human papillomaviruses (HPVs) are responsible for the development of cervical and other anogenital cancers. Intratype sequence variants of certain high-risk HPV types (e.g. 16, 18 and 31) are thought to have different oncogenic potential, partly due to nucleotide sequence variation in the viral long control region (LCR). The LCR has an important role in the regulation of viral replication and transcription. The purpose of this study was to explore sequence variation in the LCR of HPV 33 intratype variants in Hungary and to see whether there are differences in the transcriptional activities of the variants.MethodsThe complete HPV 33 LCR was amplified from HPV 33 positive cervical samples. After sequencing the LCR variants, multiple sequence alignment and phylogenetic analyses were carried out. Representative HPV 33 LCR sequence variants were selected for cloning and functional analysis. After transient transfection of HeLa cells, luciferase reporter assays were used to analyse the transcriptional activities of different LCR variants.ResultsAltogether 10 different variants were identified by sequence analysis of the HPV 33 LCR. The results of phylogenetic analysis showed that 3 variants belonged to sublineage A1, while the other 7 variants clustered with sublineage A2. Variants belonging to sublineage A2 had significantly lower transcriptional activities than variants belonging to sublineage A1. Within sublineage A2, the two variants analysed had significantly different transcriptional activities, which was shown to be caused by the A7879G variation.ConclusionsNucleotide variation in the HPV 33 LCR can result in altered transcriptional activity of the intratype variants. Our results can help to understand the correlation between LCR polymorphism and the oncogenic potential of HPV 33 variants.

Characteristics of human papillomavirus infection among females and the genetic variations of HPV18 and HPV58 in Henan province, China

The present study aims to investigate the genotype distribution of Human papillomavirus (HPV) and variations of HPV18 and HPV58 infection among 6538 females in Luoyang city during 2019–2021. The overall positive rate of females with HPV infection was 12.34%, with 9.74% were infected with single HPV and 2.60% with multiple HPVs. The prevalent rate of high-risk HPV (HR-HPV) was 9.85% and the top five HR-HPV genotypes were HPV52 (1.94%), HPV16 (1.93%), HPV58 (1.48%), HPV51 (1.02%) and HPVV39 (0.99%). Two peaks of HPV infections rates were observed in females aged ≤ 20 and 61–65 years old. To characterize mutations, 39 HPV18 and 56 HPV58 L1, E6 and E7 genes were sequenced and submitted to GenBank. In the HPV18 E6-E7-L1 sequences, 38 nucleotides changes were observed with 10/38 were non-synonymous mutations (5 in E6 gene, 1 in E7 gene and 4 in L1 gene). In the HPV58 E6-E7-L1 sequences, 53 nucleotides changes were observed with 23/53 were non-synonymous mutations (3 in E6 gene, 5 in E7 gene and 15 in L1 gene). Phylogenetic analysis based on L1 gene showed that 92.3% (36/39) of HPV18 isolates fell into sublineage A1 and 7.7% (3/39) belonged to A5. For HPV58, 75.0% (42/56) isolates belonged to sublineage A1 and 25.0% (14/56) were sublineage A2. There was no association between amino mutation and cervical lesions. The present study provides basic information about the distribution, genotypes and variations of HPV among females population in Luoyang city, which would assist in the formulation of HPV screening and vaccination programs and preventive strategies for HPV-attributable cancer in this region.

Characterization of the Human Papillomavirus 16 Oncogenes in K14HPV16 Mice: Sublineage A1 Drives Multi-Organ Carcinogenesis.

The study of human papillomavirus (HPV)-induced carcinogenesis uses multiple in vivo mouse models, one of which relies on the cytokeratin 14 gene promoter to drive the expression of all HPV early oncogenes. This study aimed to determine the HPV16 variant and sublineage present in the K14HPV16 mouse model. This information can be considered of great importance to further enhance this K14HPV16 model as an essential research tool and optimize its use for basic and translational studies. Our study evaluated HPV DNA from 17 samples isolated from 4 animals, both wild-type (n = 2) and HPV16-transgenic mice (n = 2). Total DNA was extracted from tissues and the detection of HPV16 was performed using a qPCR multiplex. HPV16-positive samples were subsequently whole-genome sequenced by next-generation sequencing techniques. The phylogenetic positioning clearly shows K14HPV16 samples clustering together in the sub-lineage A1 (NC001526.4). A comparative genome analysis of K14HPV16 samples revealed three mutations to the human papillomaviruses type 16 sublineage A1 representative strain. Knowledge of the HPV 16 variant is fundamental, and these findings will allow the rational use of this animal model to explore the role of the A1 sublineage in HPV-driven cancer.

Whole-genome analysis of human papillomavirus 67 isolated from Japanese women with cervical lesions

BackgroundHuman papillomavirus (HPV) type 67 is phylogenetically classified into Alphapapillomavirus species 9 (alpha-9) together with other carcinogenic types (HPV16, 31, 33, 35, 52 and 58), but is the only alpha-9 type defined as possibly carcinogenic. This study aimed to determine whole-genome sequences of HPV67 isolated from Japanese women with cervical cancer or cervical intraepithelial neoplasia (CIN) to better understand the genetic basis of the oncogenic potential of HPV67.MethodsTotal cellular DNA isolated from cervical exfoliated cells that were single positive for HPV67 (invasive cervical cancer, n = 2; CIN3, n = 6; CIN 2, n = 1; CIN1, n = 2; the normal cervix, n = 1) was subjected to PCR to amplify HPV67 DNA, followed by next generation sequencing to determine the complete viral genome sequences. Variant lineages/sublineages were assigned through viral whole-genome phylogenetic analysis. The transcriptional activity of the virus early promoter was assessed by luciferase reporter assays in cervical cancer cell lines.ResultsPhylogenetic analyses of HPV67 genomes from Japan (n = 12) revealed that 11 belonged to lineage A (sublineage A1, n = 9; sublineage A2, n = 2) and one belonged to lineage B. All cancer cases contained sublineage A1 variants, and one of these contained an in-frame deletion in the E2 gene. The long control region of the HPV67 genome did not induce transcription from the virus early promoter in HeLa cells, but showed weak transcriptional activity in CaSki cells.ConclusionsThe single detection of HPV67 in cervical cancer and precancer specimens strongly suggests the carcinogenic potential of this rare genotype. The phylogenetic analysis indicates a predominance of lineage A variants among HPV67 infections in Japan. Since only 23 complete genome sequences of HPV67 had been obtained until now, the newly determined genome sequences in this study are expected to contribute to further functional and evolutionary studies on the genetic diversity of HPV67.

Pathology and Characterization of Fowlpox Virus Infection in a Turkey-Chicken Backyard Flock, Nigeria

Cutaneous scabs were seen on the nares and shanks in three grower turkeys in a mixed turkey-chicken flock in Langtang-north LGA of Plateau State, Nigeria. A chicken in the flock had diphtheritic membrane covering the mucous membranes of the oro-pharynx and the turkeys had cutaneous pox lesions on the nares and shank. Fowlpox virus infection was diagnosed by gross and histopathology and confirmed by isolation of the virus in chorioallantoic membrane of 9-12 weeks chicken embryonating eggs. The DNA of Fowl Pox Virus (FPV) was detected in the cutaneous scabs of the turkey and chicken using Polymerase Chain Reaction (PCR) which amplified a 578 base pairs fragment of the 4b core protein gene. Sequencing and phylogenetic analysis revealed that the fowlpox virus responsible for this infection clustered with the sublineage A1 genotype of clade A of fowlpox virus and shares 98% homology with the vaccine strain produced in Nigeria. The sequence has been deposited in the GenBank under the accession number MK435242. Our results confirmed the presence of FPV in the turkeys and suggest a predisposition by the chickens. We therefore suggest vaccination for small holder poultry to mitigate against mortality in turkeys and chickens and molecular epidemiology of fowlpox viruses in Nigeria to unravel viral evolution.

Ancient Evolutionary History of Human Papillomavirus Type 16, 18 and 58 Variants Prevalent Exclusively in Japan.

Human papillomavirus (HPV) is a sexually transmitted virus with an approximately 8-kilo base DNA genome, which establishes long-term persistent infection in anogenital tissues. High levels of genetic variations, including viral genotypes and intra-type variants, have been described for HPV genomes, together with geographical differences in the distribution of genotypes and variants. Here, by employing a maximum likelihood method, we performed phylogenetic analyses of the complete genome sequences of HPV16, HPV18 and HPV58 available from GenBank (n = 627, 146 and 157, respectively). We found several characteristic clusters that exclusively contain HPV genomes from Japan: two for HPV16 (sublineages A4 and A5), one for HPV18 (sublineage A1) and two for HPV58 (sublineages A1 and A2). Bayesian phylogenetic analyses of concatenated viral gene sequences showed that divergence of the most recent common ancestor of these Japan-specific clades was estimated to have occurred ~98,000 years before present (YBP) for HPV16 A4, ~39,000 YBP for HPV16 A5, ~38,000 YBP for HPV18 A1, ~26,000 for HPV58 A1 and ~25,000 YBP for HPV58 A2. This estimated timeframe for the divergence of the Japan-specific clades suggests that the introduction of these HPV variants into the Japanese archipelago dates back to at least ~25,000 YBP and provides a scenario of virus co-migration with ancestral Japanese populations from continental Asia during the Upper Paleolithic period.

Lineage analysis of human papillomavirus type 39 in cervical samples of Iranian women

BackgroundThe data with regards to the regional variants of distinct HPV types is of great value. Accordance with this, this study aimed to investigate the sequence variations of E6 gene and long control region of HPV 39 among normal, premalignant and malignant cervical samples in order to characterize the frequent HPV 39 variants circulating in Tehran, Iran.MethodsIn total, 70 cervical samples (45 normal, 16 premalignant, and 9 malignant samples) infected with HPV 39 were analyzed by nested-PCR and sequencing.ResultsOur results revealed that all samples belonged to A lineage. Almost all sequences (98.6%) were classified in A1 sublineage and only one sample (1.4%) was A2 sub lineage.ConclusionsOur findings showed that lineages A, sublineage A1, is dominant in Tehran, Iran. However, the small sample size was the most important limitations of this study. Further studies with larger sample size from different geographical regions of Iran are necessary to estimate the pathogenicity risk of HPV 39 variants in this population.

Abstract PO-087: Anal cancer and its association with HPV16 lineage B in African Americans

Abstract Background: Human papillomavirus type 16 (HPV16) is one of the most common and carcinogenic HPV types associated with high risk of anal, vagina, vulva, penis and cervical neoplastic transformations. However, many genetic variants exist within this virus and not all seem to have the same carcinogenic potential. Aim: To determine HPV16 lineages and their association with risk of high-grade anal lesions in African Americans in an inner-city hospital. Methods: We reviewed medical records of 370 African Americans with anal lesions from Jan. 2007 to Dec. 2015. This study was approved by Howard University Institutional Review Board. Demographic, clinical and pathological data including HPV, HIV, HCV (hepatitis C virus), diabetes mellitus, hypertension and body mass index (BMI) were collected. DNA was extracted from a subset of HPV16-positive patients with FFPE tissue samples (72 patients, 111 samples) and used for HPV16 whole-genome sequencing. We assessed HPV16 variant lineages and associations with disease stage. Statistical analyses were performed using Chi-square tests, Student’s t-tests, and logistic regression. Odds ratios (OR) and p-values were calculated for comparisons of normal/condyloma/high-grade dysplasia (HGD) vs. squamous cell carcinoma (SCC) and for normal/condyloma vs. HGD. The most common HPV16 A1 sublineage was used as a reference in these comparisons. Results: Males represented 75% of the patients (n=276), with a median age of 44 years and BMI of 25.8 kg/m2. The frequency of condyloma, high-grade dysplasia, SCC and adenocarcinoma was 191 (52%), 26 (7%), 31 (8%) and 8 (2%), respectively. The frequency of HPV, HIV, and HCV was 231 (68%), 147 (43%) and 42 (12%), respectively. HPV and HIV were risk factors for condyloma and dysplasia (P&amp;lt;0.05). All four main lineages of HPV16 (A,B,C,D) were detected in our specimens, with sublineage A1 most common. Lineage B, also named the African-1 HPV16 lineage because it is most common in Africa, had the strongest association with SCC (OR=10.5) whether alone or in combination with lineages A4 and D (OR=10.5), although with a lower statistical significance (0.054 vs. 0.009). As for HGD, lineage B along with A4, C and D only gave an OR of 1.4. Conclusion: We show that the majority of patients with anal lesions are young males with HPV and HIV co-infections. HPV16 lineage B was associated with a high risk of SCC development. Citation Format: Hassan Ashktorab, Adeyinka Laiyemo, Lisa Mirabello, Hassan Brim. Anal cancer and its association with HPV16 lineage B in African Americans [abstract]. In: Proceedings of the AACR Virtual Conference: Thirteenth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2020 Oct 2-4. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(12 Suppl):Abstract nr PO-087.

Abstract 2027: Anal cancer among African Americans associate with HPV16 lineage B and HIV

Abstract Background: Human papillomavirus type 16 (HPV16) is one of the most common and carcinogenic HPV types associated with high risk of anal, vagina, vulva, penis and cervical neoplastic transformations. However, many genetic variants exist within this virus and not all seem to have the same carcinogenic potential. Aim: To determine HPV16 lineages and their association with risk of high-grade anal lesions in African Americans in an inner-city hospital. Methods: We reviewed medical records of 370 African Americans with anal lesions from Jan. 2007 to Dec. 2015. This study was approved by Howard University Institutional Review Board. Demographic, clinical and pathological data including HPV, HIV, HCV (hepatitis C virus), diabetes mellitus, hypertension and body mass index (BMI) were collected. DNA was extracted from a subset of HPV16-positive patients with FFPE tissue samples (72 patients, 111 samples) and used for HPV16 whole-genome sequencing. We assessed HPV16 variant lineages and associations with disease stage. Statistical analyses were performed using Chi-square tests, Student's t-tests, and logistic regression. Odds ratios (OR) and p-values were calculated for comparisons of normal/condyloma/high-grade dysplasia (HGD) vs. squamous cell carcinoma (SCC) and for normal/condyloma vs. HGD. The most common HPV16 A1 sublineage was used as a reference in these comparisons. Results: Males represented 75% of the patients (n=276), with a median age of 44 years and BMI of 25.8 kg/m2. The frequency of condyloma, high-grade dysplasia, SCC and adenocarcinoma was 191 (52%), 26 (7%), 31 (8%) and 8 (2%), respectively. The frequency of HPV, HIV, and HCV was 231 (68%), 147 (43%) and 42 (12%), respectively. HPV and HIV were risk factors for condyloma and dysplasia (P&amp;lt;0.05). All four main lineages of HPV16 (A,B,C,D) were detected in our specimens, with sublineage A1 most common. Lineage B, also named the African-1 HPV16 lineage because it is most common in Africa, had the strongest association with SCC (OR=10.5) whether alone or in combination with lineages A4 and D (OR=10.5), although with a lower statistical significance (0.054 vs. 0.009). As for HGD, lineage B along with A4, C and D only gave an OR of 1.4. Conclusion: We show that the majority of patients with anal lesions are young males with HPV and HIV co-infections. HPV16 lineage B was associated with a high risk of SCC development. Citation Format: Hassan Brim, Lisa Mirabello, Ali Afsari, Muneer Abbas, Meredith Yeager, Joseph Boland, Sara Bass, Mia Steinberg, Michael Cullen, Adeyinka Laiyemo, Tammy Naab, Babak Shokrani, Edward Lee, Mehdi Nouraie, Hassan Ashktorab. Anal cancer among African Americans associate with HPV16 lineage B and HIV [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 2027.

Molecular epidemiology of human papillomavirus 18 infections in Japanese Women

Among the oncogenic genotypes of human papillomavirus (HPV), HPV18 is the second most common type detected in cervical cancer worldwide and is primarily involved in the generation of cervical adenocarcinoma. Although HPV intra-type variants confer different risks of cervical carcinogenesis, there is little information on the genetic diversity of HPV18 compared to the most prevalent type, HPV16. In this study, we investigated the genetic variation of HPV18 in cervical specimens obtained from Japanese women with normal cervices or cervical cancers and precancers. Of the 101 HPV18-positive samples analyzed, viral whole genome amplification followed by next-generation sequencing led to the determination of viral complete genome sequences of 18 samples. Phylogenetic analysis of these HPV18 whole genome sequences identified a distinct variant cluster consisting of only Japanese samples (n = 7) belonging to sublineage A1. Viral genome sequences were also analyzed for the E6/E7 (n = 66) and E2 (n = 27) genes by Sanger sequencing. Phylogenetic analyses of these regions showed that the variant distribution among Japanese women was strongly biased toward sublineage A1 (72 of 87; 82.8%). No significant differences were observed in the prevalence of specific sublineages between cervical cancer/precancer cases and controls, and between squamous cell carcinoma and adenocarcinoma cases. These data contribute to our understanding of the genetic diversity of HPV18 in Japanese women.

Whole-Genome Analysis of Human Papillomavirus Type 16 Prevalent in Japanese Women with or without Cervical Lesions.

Recent large-scale genomics studies of human papillomaviruses (HPVs) have shown a high level of genomic variability of HPV16, the most prevalent genotype in HPV-associated malignancies, and provided new insights into the biological and clinical relevance of its genetic variations in cervical cancer development. Here, we performed deep sequencing analyses of the viral genome to explore genetic variations of HPV16 that are prevalent in Japan. A total of 100 complete genome sequences of HPV16 were determined from cervical specimens collected from Japanese women with cervical intraepithelial neoplasia and invasive cervical cancer, or without cervical malignancies. Phylogenetic analyses revealed the variant distribution in the Japanese HPV16 isolates; overall, lineage A was the most prevalent (94.0%), in which sublineage A4 was dominant (52.0%), followed by sublineage A1 (21.0%). The relative risk of sublineage A4 for cervical cancer development was significantly higher compared to sublineages A1/A2/A3 (odds ratio = 6.72, 95% confidence interval = 1.78–28.9). Interestingly, a novel cluster of variants that branched from A1/A2/A3 was observed for the Japanese HPV16 isolates, indicating that unique HPV16 variants are prevalent among Japanese women.

Genetic variability and oncogenic risk association of human papillomavirus type 58 E6 and E7 genes in Taizhou area, China

It is well recognized that the association of human papillomavirus (HPV) and cervical carcinogenesis is based on the presence of HPV DNA sequence. The E6 and E7 oncoproteins encoded by high-risk HPV types play a key role in carcinogenesis. HPV58 type accounts for a larger share of cervical disease in China, whereas data on HPV58 genetic variability in China is limited. We aimed to evaluate the diversity of HPV58 genetic variants by sequencing the entire E6 and E7 genes. Phylogenetic trees were constructed by Maximum likelihood method by MEGA 5.05 software. In this study, the overall HPV infection rate was 22.6% (2891/12780) in Southeast China and the prevalence of HPV58 infection rate was 2.6% (335/12780). 26 nucleotides substitutions were observed in E6 and E7 genes with 10 novel substitutions and 17 non-synonymous substitutions. We obtained 25 distinct variation patterns which the accession GenBank numbers as MH348918-MH348942. All of HPV58 variants belong to lineage A, while no lineage B, C and D were detected in Taizhou area, Southeast China. The sublineage A1, A2, and A3 variants were found in 136 (68.3%), 39 (19.6%), and 24 (12.1%) of HPV58 isolates, respectively. The sublineage A3 variants with T20I/G63S substitutions at E7 oncoprotein carried a significantly higher risk for high-grade cervical intraepithelial neoplasia (CIN2 or worse, CIN2+) when compared with other HPV58 variants (odds ratio = 4.41, P < 0.05). Nevertheless, there was no association between HPV58 (sub) lineages and cervical lesions. These data provide the critical characteristics of HPV58 variants to assist further investigation of carcinogenic association and the development of next generation vaccines and diagnostic assays in China.

Impact of Naturally Occurring Variation in the Human Papillomavirus 58 Capsid Proteins on Recognition by Type-Specific Neutralizing Antibodies.

Naturally occurring variants of human papillomavirus (HPV) 58 have been defined as lineages and sublineages but little is known about the impact of this diversity on protein function. We investigated the impact of variation within the major (L1) and minor (L2) capsid proteins of HPV58 on susceptibility to neutralizing antibodies. Pseudovirus (PsV) representing A1, A2, A3, B1, B2, C, D1, and D2 variants were evaluated for their susceptibility to antibodies elicited during natural infection, preclinical antisera generated against virus-like particles, and monoclonal antibodies (MAbs). Lineage C PsV demonstrated a decreased sensitivity to antibodies raised against lineage A antigens. Exchange of the DE, FG, and/or HI loops between sublineage A1 and lineage C demonstrated that residues within all 3 loops were essential for the differential sensitivity to natural infection antibodies, with slightly different requirements for the animal antisera and MAbs. Comparison between the HPV58 A1 L1 pentamer crystal structure and an HPV58 C homology model indicated that these differences in neutralization sensitivity were likely due to subtle epitope sequence changes rather that major structural alterations. These data improve our understanding of the impact of natural variation on HPV58 capsid antigenicity and raise the possibility of lineage-specific serotypes.

Human papillomavirus (HPV) 18 genetic variants and cervical cancer risk in Taizhou area, China

Human papillomavirus (HPV) type 18 is predominantly associated with the development of cervical adenocarcinomas, whereas data on HPV18 genetic variability in China are limited. HPV18 genetic variants were formed phylogenetic tree, including lineages A, B, and C. We aimed to evaluate the diversity of HPV18 genetic variants by sequencing the entire E6, E7 and L1 genes. Between 2012 and 2015, a total of 138 (0.8%, 138/17669) women with single HPV18 infection were selected in this study. Finally, we observed 122 HPV18 isolates of the complete E6-E7-L1 sequences, and obtained 36 distinct variation patterns which the accession GenBank numbers as KY457805-KY457840. Except KY457805, KY457813, KY457819, KY457827, KY457829, the rest of HPV18 isolates (81.1%, 31/36) are novel variants. All of HPV18 variants belong to lineage A, while no lineage B, and C was found in our population of Taizhou region, Southeast China. Sublineage A1 was the most common variants (85.2%, 104/122), followed by sublineage A4, A3 and A5, while no sublineage A2 was obtained. Based on the tree topologies, there were three newly identified candidates' sublineages A6-A8. Out of 122 women, 67 (54.9%) had diagnosed by biopsy, including 49 women who diagnosed with cervicitis, 12 with cervical intraepithelial neoplasia (CIN)1, 4 with CIN2/3, and 2 with adenocarcinomas, respectively. Nevertheless, there was no association between HPV18 (sub) lineages and CIN1 or worse (CIN1+) lesions comparing with normal biopsies (P = .469). In conclusion, knowledge of the distribution of geographic/ethnical HPV18 genetic diversity provides critical information for developing diagnostic probes, epidemiologic correlate of cervical cancer risk and design of HPV vaccines for targeted populations.

Genetic Variability of the Medicinal Tinder Bracket Polypore, Fomes fomentarius (Agaricomycetes), from the Asian Part of Russia

We analyzed intraspecies genetic variability of the medicinal tinder bracket polypore, Fomes fomentarius, from the Asian part of Russia, including the Ural, Altai, Western Sayan, and Baikal regions. We used nuclear ribosomal DNA internal transcribed spacer (ITS) sequence data as a standard marker for fungal DNA barcoding. In the Asian part of Russia, lineage A occurs as sublineage A2, which differs from sublineage A1 by a single nucleotide insertion at ITS2.3. Sublineage A2 is distributed up to Lake Baikal in the Ural, Altai, and Western Sayan regions. It can be characterized as a Eurasian sublineage of F. fomentarius. Lineage B is also represented by 2 sublineages (B1 and B2), which differ from each other by nucleotide sequences at ITS2.1. Sublineage B1 is represented by a small group of isolates from Asia (Iran, China, Nepal, South Korea), whereas sublineage B2 mainly includes isolates from Europe (Great Britain, Italy, Latvia, Slovakia, Slovenia) and 2 separate samples from Asia (Iran, China); these locales compose the distribution area of F. fomentarius. In the Asian part of Russia, lineage B is represented by sublineage B2 found in the Southern Urals (at the border between Europe and Asia), which is the only area where sublineages A2 and B2 are present. These sublineages are characterized by different substrate spectra: sublineage A2 is predominantly associated with Betula spp. and rarely with Alnus and Larix trees, whereas sublineage B2 does not have a pronounced substrate preference and is found in basidiomes collected from Acer, Duschekia, Prunus, and Salix trees, but not Betula trees. In general, the spectrum of substrates for F. fomentarius lineages A and B in the Asian part of Russia corresponds to that in other parts of this polypore's distribution area. Data are needed on genetic intraspecies variability (polymorphism) in relation to pharmacological properties for further biotechnological cultivation and use of the medicinal fungus F. fomentarius.