Distribution of HPV 16 E6 gene variants in screening women and its associations with cervical lesions progression

HPV-16 E6 mutation and viral integration related host DNA methylation implicate the development and progression of cervical cancer

BACKGROUND

HPV-16 infection and viral-host integration are the most important risk factors for cervical cancer (CC). The aim of this study is to develop a new molecular strategy integrated both the viral and host genome variations identifying and monitoring CC.

METHOD

A total of 312 methylation and 538 RNA-seq datasets were collected from public databases to identify differentially methylated and expressed genes. HPV associated virus integration sites (VISs) were analysed using the ViMIC database. From September 2020 to August 2021, the 70 HPV-16 positive cases retrospectively collected from multi-centre cohorts were subjected to HPV-16 E6 deep sequencing and PCR-based host gene (ASTN1, DLX1, ITGA4, RXFP3, SOX17, ZNF671) methylation detection. RNAseq and expression validation (NNF671) were performed in C-33A cell line harbouring HPV D32E. Lasso and logistic regression algorithm were used to construct the CC diagnostic model.

RESULTS

A positive correlation was observed between the average methylation level of CC patients and their pathological features including tumour stage (p = 0.0077) and HPV subtype (p < 0.001). ZNF671 was identified as a CC-specific methylation marker, with an impressive 93% sensitivity. Both HPV-16 D32E mutation and integration of HPV-16 down-regulated the ZNF671 expression. Finally, a CC diagnostic nomogram was developed by integrating ZNF671 methylation level and HPV E6 mutation feature, yielding an exceptional AUC of 0.997 (95% CI: 0.934-1.000).

CONCLUSIONS

Our study demonstrated HPV viral mutations are closely related to host gene epigenetic alterations in CC. Integration of the viral and host genetic information might be a new promising strategy for CC screening.

Genetic Variability in the E6, E7, and L1 Genes of Human Papillomavirus Types 16 and 18 among Women in Saudi Arabia

Cervical cancer is the eighth most frequent cancer in Saudi Arabia, and most cases are associated with human papillomavirus (HPV) types 16 and 18. HPV-induced carcinogenesis may be associated with the intra-type variant, genetic mutation, or the continuous expression of viral oncogenes E6 and E7. Infection efficiency and virus antigenicity may be affected by changes in the L1 gene. Thus, this retrospective cohort study analyzed E6, E7, and L1 gene mutations in cervical specimens collected from Saudi women positive for HPV16 or HPV18 infection. HPV16 and HPV18 lineages in these specimens were predominantly from Europe. The L83V mutation in the E6 gene of HPV16 showed sufficient oncogenic potential for progression to cervical cancer. By contrast, the L28F mutation in the E7 gene of HPV16 was associated with a low risk of cervical cancer. Other specific HPV16 and HPV18 mutations were associated with an increased risk of cancer, cancer progression, viral load, and age. Four novel mutations, K53T, K53N, R365P, and K443N, were identified in the L1 gene of HPV16. These findings for HPV16 and HPV18 lineages and mutations in the E6, E7, and L1 genes among women in Saudi Arabia may inform the design and development of effective molecular diagnostic tests and vaccination strategies for the Saudi population.

Comprehensive Viral Genotyping Reveals Prognostic Viral Phylogenetic Groups in HPV16-Associated Squamous Cell Carcinoma of the Oropharynx

Human papillomavirus-positive (HPV+) squamous cell carcinoma of the oropharynx (OPSCC) is the most prevalent HPV-associated malignancy in the United States and is primarily caused by HPV subtype 16 (HPV16). Favorable treatment outcomes have led to increasing interest in treatment deescalation to reduce treatment-related morbidity. Prognostic biomarkers are needed to identify appropriately low-risk patients for reduced treatment intensity. Targeted DNA sequencing including all HPV16 open reading frames was performed on tumors from 104 patients with HPV16+ OPSCC treated at a single center. Genotypes closely related to the HPV16-A1 reference were associated with increased numbers of somatic copy-number variants in the human genome and poor recurrence-free survival (RFS). Genotypes divergent from HPV16-A1 were associated with favorable RFS. These findings were independent of tobacco smoke exposure. Total RNA sequencing was performed on a second independent cohort of 89 HPV16+ OPSCC cases. HPV16 genotypes divergent from HPV16-A1 were again validated in this independent cohort, to be prognostic of improved RFS in patients with moderate (less than 30 pack-years) or low (no more than 10 pack-years) of tobacco smoke exposure. In summary, we show in two independent cohorts that viral sequence divergence from the HPV16-A1 reference is correlated with improved RFS in patients with moderate or low tobacco smoke exposure.

IMPLICATIONS

HPV16 genotype is a potential biomarker that could be easily adopted to guide therapeutic decision-making related to deescalation therapy.

Genetic diversity of E6, E7 and the long control region in human papillomavirus type 16 variants in Beijing, China

Background

High-risk human papillomavirus type 16 (HPV16) is a risk factor for cervical cancer. The progression from initial infection to cervical cancer has been linked to properties of the viral sequences. However, the distribution of HPV16 variants among Chinese women has not been extensively addressed and the role of HPV16 variants in the risk of cervical carcinogenesis remains poorly understood.

Methods

HPV16 positive cervical exfoliated cell samples were collected from 249 women living in Beijing, China. PCR products from two fragments of E6-E7 and LCR of HPV16 in these samples were sequenced and analyzed.

Results

Lineage A was found in the subjects, including A1, A2, A3 and A4 sublineages. Based on the HPV16 reference sequences, 26 nucleotide mutations of A4 sublineage and 39 nucleotide mutations of A1-3 sublineages were found in the E6, E7 and LCR of HPV16 isolates. Point mutations T843C, A7287C and A7872G of A4 sublineage were significantly associated with high-grade cervical lesions. The high-frequency sites in HPV16 LCR located at regions that can bind to multiple transcription factors.

Conclusions

This study contributes to the identification of unique variants in the E6, E7 and LCR of HPV16 isolates infected in Chinese women. Mutations of T843C, A7287C and A7872G in A4 sublineages were significantly associated with high-grade cervical lesions, suggesting that mutations in the E7 and LCR region have potential effects on viral replication and progression of cervical cancer.

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Lineage A is the predominant HPV16 variant in Chinese women.

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Based on the HPV16 prototype, 25 nucleotide mutations in E6 and E7 were found and 41 nucleotide mutations in LCR were found.

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The mutations of C843T, A7287C and A7872G were significantly correlated with the cervical lesions.

Targeted Next Generation Sequencing for Human Papillomavirus Genotyping in Cervical Liquid-Based Cytology Samples

At present, human papillomavirus (HPV) testing is replacing morphology-based cytology as the primary tool for cervical cancer screening in several countries. However, the HPV assays approved for screening lack detection for all but one of the possibly carcinogenic HPV types and do not genotype all included HPV types. This study demonstrates the use of a targeted HPV next generation sequencing (NGS) panel to detect and genotype all 25 carcinogenic, probably carcinogenic, and possibly carcinogenic HPV types as well as the low-risk types HPV6 and HPV11. The panel was validated using a cohort of 93 paired liquid-based cytology samples (general practitioner (GP)-collected cervical samples and cervico-vaginal self-samples (SS)). Overall, the targeted panel had a sensitivity (GP = 97.7%, SS = 92.1%) and specificity (GP = 98.0%, SS = 96.4%) similar to the commercial HPV assays, Cobas® 4800 HPV DNA test (Roche) and CLART® HPV4S assay (GENOMICA). Interestingly, of the samples that tested positive with the NGS panel, three (6.4%) of the GP-collected samples and four (9.1%) of the self-samples tested positive exclusively for HPV types only included in the NGS panel. Thus, targeted HPV sequencing has great potential to improve the HPV screening programs since, as shown here, it can identify additional HPV positive cases, cases with HPV integration, variants in the HPV genome, and which HPV type is dominant in multi-infected cases.

Genetic variation in the E6 and E7 genes of human papillomavirus type 16 in northeastern Argentina

The province of Misiones is considered a region with a high mortality rate due to cervical cancer (CC). To gain insight into this problem, we explored the association between genetic variation in the E6 and E7 oncogenes of HPV16 and the risk of CC. We studied 160 women with cytological diagnoses of negative for intraepithelial lesion or malignity, low-grade squamous intraepithelial lesion, and high-grade squamous intraepithelial lesion/CC and a positive test for HPV16 infection. The genetic characterization of E6 and E7 genes was undertaken through PCR amplification and direct Sanger sequencing. Phylogenetic classification was conducted using Bayesian methods. To estimate the odds ratio (OR) for an association between genetic variants in the E6 and E7 genes and the risk of CC, we used ordinal logistic regression adjusted by age. The final data set comprised 112 samples. Diagnostic single-nucleotide polymorphisms (SNPs) and phylogenetic trees confirmed the presence of Lineage A (95.5%) and D (4.5%) in the samples. For the E6 gene, we identified eleven different sequences, with the most common ones being Lineage A E6 350G (58.9%) and E6 350T (37.5%). The E6 350G was associated with progression to HSIL/CC, with an OR of 19.41 (4.95-76.10). The E7 gene was more conserved than E6, probably due to the functional constraints of this small protein. Our results confirmed the association of the E6 350G SNP with a higher risk of developing CC. These data will contribute to understanding the biological bases of CC incidence in this region.

Usefulness of E7 mRNA in HPV16-Positive Women to Predict the Risk of Progression to HSIL/CIN2

Objective: To evaluate whether E7 mRNA can predict the risk of progression in women with HPV16 infection. Design: A prospective observational study. Setting: A tertiary university hospital. Population: A cohort of 139 women referred to colposcopy for an abnormal screening result fulfilling the following inclusion criteria: (1) a positive test result confirming HPV16 infection; (2) a biopsy sample with a histological diagnosis of an absence of lesion or low-grade SIL/CIN grade1 (LSIL/CIN1); (3) no previous HPV vaccination; (4) no pregnancy; and (5) no previous cervical treatments; and (6) no immunosuppression. Methods: At the first visit, all women underwent a cervical sample for liquid-based cytology, HPV testing and genotyping, and HPV16 E7 mRNA analysis and a colposcopy with at least one colposcopy-guided biopsy. Follow-up visits were scheduled every six months. In each control, a liquid-based Pap smear, HPV testing, as well as a colposcopy examination with biopsy if necessary were performed. Main outcome measures: Histological diagnosis of HSIL/CIN2+ at any time during follow-up. Results: E7 mRNA expression was positive in 55/127 (43.3%) women included in the study and seven (12.7%) progressed to HSIL/CIN2+. In contrast, only 1/72 (1.4%) women with no HPV16 E7 mRNA expression progressed (p = 0.027). HPV16 E7 mRNA expression was associated with a 10-fold increased risk of progression (HR 10.0; 95% CI 1.2–81.4). Conclusions: HPV16 E7 mRNA could be useful for risk stratification of women with HPV16 infection in whom a HSIL/CIN2+ has been ruled out. Funding: Instituto de Salud Carlos III (ICSIII)-Fondo de Investigación Sanitaria and ERDF ‘One Way to Europe’ (PI17/00772).

AutoVEM2: A flexible automated tool to analyze candidate key mutations and epidemic trends for virus

In our previous work, we developed an automated tool, AutoVEM, for real-time monitoring the candidate key mutations and epidemic trends of SARS-CoV-2. In this research, we further developed AutoVEM into AutoVEM2. AutoVEM2 is composed of three modules, including call module, analysis module, and plot module, which can be used modularly or as a whole for any virus, as long as the corresponding reference genome is provided. Therefore, it's much more flexible than AutoVEM. Here, we analyzed three existing viruses by AutoVEM2, including SARS-CoV-2, HBV and HPV-16, to show the functions, effectiveness and flexibility of AutoVEM2. We found that the N501Y locus was almost completely linked to the other 16 loci in SARS-CoV-2 genomes from the UK and Europe. Among the 17 loci, 5 loci were on the S protein and all of the five mutations cause amino acid changes, which may influence the epidemic traits of SARS-CoV-2. And some candidate key mutations of HBV and HPV-16, including T350G of HPV-16 and C659T of HBV, were detected. In brief, we developed a flexible automated tool to analyze candidate key mutations and epidemic trends for any virus, which would become a standard process for virus analysis based on genome sequences in the future.

HLA-G polymorphism impacts the outcome of oral HPV infections in women

BACKROUND

Human leukocyte antigen (HLA)-G may have an important role in the natural history of human papillomavirus (HPV) infection. Our aim was to evaluate the role of HLA-G in the outcome of genital and oral HPV infections in women.

METHODS

Analyses included 306 women from the Finnish Family HPV-study and were followed-up for six years. Genital and oral samples were tested for 24 different HPV types with multiplex HPV genotyping. HLA-G alleles were determined through direct DNA-sequencing. Unconditional logistic regression was used to determine the associations between HLA-G genotypes and HPV infection outcomes.

RESULTS

Ten HLA-G alleles were identified. Most common HLA-G genotypes were the wild type G*01:01:01/01:01:01 (31.3%) followed by G*01:01:01/01:01:02 (26.8%). G*01:01:01/01:01:01 genotype was associated with increased risk of oral HPV infections by any HPV type or single-type with OR = 1.86 (95% CI 1.14-3.04, P = 0.01) and 2.22 (95% CI 1.14-3.71, P = 0.02), respectively. G*04:01+ allele and the G*01:01:01/01:04:01 genotype both protected from any and single oral HPV infections; OR = 0.46 (95% CI 0.23-0.89, P = 0.02) and 0.53 (95% CI 0.23-0.97, P = 0.03), respectively. G*01:01:02/01:04:01 genotype increased significantly the risk of infertility and its treatments, with respective OR = 5.06 (95% CI 1.22-21.02, P = 0.03) and OR = 9.07 (95% CI 1.22-39.50, P = 0.03). Both HLA-G alleles and genotypes showed several significant associations with the outcomes of oral HPV infections, but none of them had any impact on the outcomes of genital HPV infections in these women.

CONCLUSIONS

The host HLA-G genotypes appear to impact the outcomes of oral HPV infections in women but have little if any effect on genital HPV status or infection outcomes.

Epidemiology and Burden of Human Papillomavirus and Related Diseases, Molecular Pathogenesis, and Vaccine Evaluation

Diagnosed in more than 90% of cervical cancers, the fourth deadliest cancer in women, human papillomavirus (HPV) is currently the most common pathogen responsible for female cancers. Moreover, HPV infection is associated with many other diseases, including cutaneous and anogenital warts, and genital and upper aerodigestive tract cancers. The incidence and prevalence of these pathologies vary considerably depending on factors including HPV genotype, regional conditions, the study population, and the anatomical site sampled. Recently, features of the cervicovaginal microbiota are found to be associated with the incidence of HPV-related diseases, presenting a novel approach to identify high-risk women through both blood and cervical samples. Overall, the HPV repartition data show that HPV infection and related diseases are more prevalent in developing countries. Moreover, the available (2-, 4-, and 9-valent) vaccines based on virus-like particles, despite their proven effectiveness and safety, present some limitations in terms of system development cost, transport cold chain, and oncogenic HPV variants. In addition, vaccination programs face some challenges, leading to a considerable burden of HPV infection and related diseases. Therefore, even though the new (9-valent) vaccine seems promising, next-generation vaccines as well as awareness programs associated with HPV vaccination and budget reinforcements for immunization are needed.

Role of HPV 16 variants among cervical carcinoma samples from Northeastern Brazil

BACKGROUND

Cervical cancer is the fourth most common type of cancer affecting women globally. In Brazil, it is the third most frequent type of cancer in women and HPV is present in approximately 90% of cases. Evidence suggests that variants of HPV 16 can interfere biologically and etiologically during the development of cervical cancer.

METHODS

Cervix tumor fragments were collected, their DNA was extracted, and nested PCR was used to detect HPV. Positive samples were sequenced to determine the viral genotype. To characterize the HPV 16 strains, positive samples PCR was used to amplify the LCR and E6 regions of the HPV 16 virus.

RESULTS

Data from 120 patients with cervical cancer were analyzed. Most women were between 41 and 54 years of age, had schooling until primary school, a family income between 1 and 2 times the minimum wage and were married/in a consensual union. There was no statistically significant association between HPV or socio-demographic variables and risk factors for cervical cancer (P <  0.05). HPV was present in 88 women (73%). The most prevalent types were HPV 16 (53.4%), HPV 18 (13.8%), HPV 35 (6.9%) and HPV 45 (5.7%). Of the 47 HPV 16 positive cases, variant A (49%) was present in 23 samples, followed by variant D in 20 cases (43%), and variants B and C in 2 cases each (4%). The most prevalent histological type of HPV 16 tumors was squamous cell carcinoma, followed by adenocarcinoma. There was a statistically significant association between HPV 16 variants and the tumors' histological types (P <  0.001).

CONCLUSIONS

Knowledge of HPV 16 variants will provide data on their influence on the pathological and oncogenic aspects of cervical lesions.