Distribution of human papillomavirus types in cervical cancers in Hong Kong: Current situation and changes over the last decades

Maximizing the cost-effectiveness of cervical screening in the context of routine HPV vaccination by optimizing screening strategies with respect to vaccine uptake: a modeling analysis

BACKGROUND

Regarding primary and secondary cervical cancer prevention, the World Health Organization proposed the cervical cancer elimination strategy that requires countries to achieve 90% uptake of human papillomavirus (HPV) vaccines and 70% screening uptake. The optimal cervical screening strategy is likely different for unvaccinated and vaccinated cohorts upon national HPV immunization. However, health authorities typically only provide a one-size-fits-all recommendation for the general population. We aimed to evaluate the cost-effectiveness for determining the optimal screening strategies for vaccinated and unvaccinated cohorts.

METHODS

We considered the women population in Hong Kong which has a unique HPV infection and cervical cancer epidemiology compared to other regions in China and Asia. We used mathematical models which comprise a deterministic age-structured compartmental dynamic component and a stochastic individual-based cohort component to evaluate the cost-effectiveness of screening strategies for cervical screening. Following the recommendations in local guidelines in Hong Kong, we considered strategies that involved cytology, HPV testing, or co-testing as primary cervical screening. We also explored the impacts of adopting alternative de-intensified strategies for vaccinated cohorts. The 3-year cytology screening was used as the base comparator while no screening was also considered for vaccinated cohorts. Women's lifetime life years, quality-adjusted life years, and costs of screening and treatment were estimated from the societal perspective based on the year 2022 and were discounted by 3% annually. Incremental cost-effectiveness ratios (ICERs) were compared to a willingness to pay (WTP) threshold of one gross domestic product per capita (US $47,792). Probabilistic and one-way sensitivity analyses were conducted.

RESULTS

Among unvaccinated cohorts, the strategy that adds reflex HPV to triage mild cytology abnormality generated more life years saved than cytology-only screening and could be a cost-effective alternative. Among vaccinated cohorts, when vaccine uptake was 85% (based on the uptake in 2022), all guideline-based strategies (including the cytology-only screening) had ICERs above the WTP threshold when compared with no screening if the vaccine-induced protection duration was 20 years or longer. Under the same conditions, HPV testing with genotyping triage had ICERs (compared with no screening) below the WTP threshold if the routine screening interval was lengthened to 10 and 15 years or screening was initiated at ages 30 and 35 years.

CONCLUSIONS

HPV testing is a cost-effective alternative to cytology for vaccinated cohorts, and the associated optimal screening frequency depends on vaccine uptake. Health authorities should optimize screening recommendations by accounting for population vaccine uptake.

The impact and cost-effectiveness of 9-valent human papillomavirus vaccine in adolescent females in Hong Kong

Introduction

In Hong Kong (HK), a single-cohort vaccination program for 10–12-year-old girls with the 9-valent human papillomavirus (HPV) vaccine (9vHPV; types 6/11/16/18/31/33/45/52/58) has been launched. This study assessed the public health impact and cost-effectiveness of implementing routine 9vHPV vaccination (12-year-olds) with or without catch-up 9vHPV vaccination (13–18-year-olds) in HK.

Methods

The health impact and costs of implementing routine 9vHPV vaccination with or without catch-up vaccination over a 100-year time horizon were evaluated using a validated HPV-type transmission dynamic model adapted to the HK population; analyses were performed from a healthcare payer perspective. Routine vaccination (12-year-old girls) and catch-up vaccination (13–18 years) assumed vaccine coverage rates of 70% (base case) and 30%, respectively. The model also assumed herd immunity, lifelong vaccine protection, a discount rate of 3%, and a cost per dose of HK dollars (HKD) 858 [United States dollars (USD) 110] and HKD 1390 (USD 179) for the 2-valent HPV (2vHPV) and 9vHPV vaccines, respectively. HPV disease-related incidence and the incremental cost-effectiveness ratio (ICER) per quality-adjusted-life-year (QALY) were estimated. Cost-effectiveness was determined at a ceiling threshold of HK dollars (HKD) 382,046 (USD 49,142) or 1.0 times the gross domestic product per capita of HK.

Results

Compared with routine 9vHPV alone, routine plus catch-up 9vHPV is projected to reduce cervical cancer incidence by 3.4%. Routine plus catch-up 9vHPV will also reduce genital warts incident cases for males/females by 2.6%/5.4%. The incremental cost-effectiveness ratios were HKD 29,911 (USD 3847)/quality-adjusted life-year (QALY) for routine plus catch-up 9vHPV versus routine 9vHPV alone and HKD 25,524 (USD 3283)/QALY for routine 9vHPV alone versus screening only. Sensitivity analyses indicated that routine plus catch-up 9vHPV compared with routine 9vHPV alone remained cost-effective at coverage rates of 30% and 90%.

Conclusions

This analysis predicts that the current HK vaccination strategy can be considered cost-effective and will provide maximum health benefit. These results support addition of the routine 9vHPV vaccine with or without catch-up 9vHPV vaccination to the regional vaccination program in HK.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12962-021-00328-x.

Association of human papillomavirus genotype distribution and cervical cytology: a cross-sectional study

The present study attempted to analyse human papillomavirus (HPV) genotype distribution and its association with cervical cytology results in women in western China. The present retrospective analysis was performed in 1089 female outpatients with a positive HPV test result who had undergone a cervical cytology test at the gynaecological clinic, West China Second Hospital, Sichuan University, China, between January 2014 and December 2016. Of the 1089 patients with HPV infection, multiple HPV genotypes were detected in 220 patients (20.20%). Among the 1368 HPV genotypes detected, 1145 (83.70%) were high-risk subtypes. The most common genotypes were HPV-52 (18.64%), HPV-16 (16.59%), HPV-58 (13.23%), HPV-18 (6.80%), HPV-56 (5.56%) and HPV-59 (5.56%). Cervical cytology revealed abnormal cells in 430 (39.49%) patients. The most common diagnoses were atypical squamous cells of undetermined significance (ASC-US; 236 cases, 54.88%), low-grade squamous intraepithelial lesions (LSIL; 151 cases, 35.12%), high-grade squamous intraepithelial lesions (HSIL; 63 cases, 14.65%) and atypical glandular cells (AGC; 21 cases, 4.88%). HPV-66 was significantly associated (P = 0.037) with ASC; HPV-52 and HPV-56 were significantly associated with LSIL (P = 0.009 and 0.026, respectively); HPV-16 (P < 0.001), HPV-33 (P = 0.014) and HPV-58 (P = 0.003) were significantly associated with HSIL; and HPV-16 (P = 0.005) was significantly associated with AGC. HPV-16, HPV-52 and HPV-58 are associated with different diagnoses in patients with positive cervical cytological findings.

Human papillomavirus genotype-specific risks for cervical intraepithelial lesions

Prevalence of different HPV genotypes is changing after HPV vaccination. The associated risks are needed for optimizing cervical cancer screening.To estimate HPV type-specific prevalence, odds ratio (OR), and positive predictive value (PPV) for cervical cytological abnormalities, we determined 41 different HPV genotypes in cervical samples from a population-based sample of 8351 women aged 18-51 years before HPV vaccination era (V501-033; NCT01077856).Prevalence of HPV16 was 4.9% (95% CI: 4.4-5.5) with the PPV for high-grade cytology 11.2%, and OR 11.9 (95% CI: 8.5-16.5). Carcinogenic HPVs included in the nonavalent vaccine (HPV16,18,31,33,45,52,58) had a population prevalence of 14.4% (95% CI: 13.5-15.4), with PPV of 8.0% (95% CI: 6.8-9.3) and OR 23.7 (95% CI: 16.0-63.5) for high-grade cytology. HPV types currently included in most screening tests, but not vaccinated against (HPV35,39,51,56,59,66,68) had a joint prevalence of 8.5% (95% CI: 7.8-9.2) with PPV of 4.4% (95% CI: 3.3-5.7) and OR of 2.9 (95% CI: 2.0-4.0) for high-grade cytology. The other 27 non-carcinogenic genotypes had a prevalence of 11.8%, PPV of 2.9% (95% CI:2.1-3.9), and OR 1.5 (95% CI: 1.1-2.2.) for high-grade cytology.These results suggest that HPV screening tests in the post-vaccination era might perform better if restricted to the HPV types in the nonavalent vaccine and screening for all 14 HPV types might result in suboptimal balance of harms and benefits.

Genetic variability, phylogeny and functional implication of the long control region in human papillomavirus type 16, 18 and 58 in Chengdu, China

BACKGROUND

Long control region (LCR) of human papillomavirus (HPV) has shown multiple functions on regulating viral transcription. The variations of LCR related to different lineages/sub-lineages have been found to affect viral persistence and cervical cancer progression differently. In this study, we focused on gene polymorphism of HPV16/18/58 LCR to assess the effect variations caused on transcription factor binding sites (TFBS) and provided more data for further study of LCR in Southwest China.

METHODS

LCR of HPV16/18/58 were amplified and sequenced to do polymorphic and phylogenetic anlysis. Sequences of each type were aligned with the reference sequence by MEGA 6.0 to identify SNPs. Neighbor-joining phylogenetic trees were constructed using MEGA 6.0. Transcription factor binding sites were predicted by JASPAR database.

RESULTS

The prevalence of these three HPVs ranked as HPV16 (12.8%) > HPV58 (12.6%) > HPV18 (3.5%) in Chengdu, Southwest China. 59 SNPs were identified in HPV16-LCR, 18 of them were novel mutations. 30 SNP were found in HPV18-LCR, 8 of them were novel. 55 SNPs were detected in HPV58-LCR, 18 of them were novel. Also, an insertion (CTTGTCAGTTTC) was detected in HPV58-LCR between position 7279 and 7280. As shown in the neighbor-joining phylogenetic trees, most isolates of HPV16/18/58 were clustered into lineage A. In addition, one isolate of HPV16 was classified into lineage C and 3 isolates of HPV58 were classified as lineage B. JASPAR results suggested that TFBS were potentially influenced by 7/6 mutations on LCR of HPV16/18. The insertion and 5 mutations were shown effects in LCR of HPV58.

CONCLUSION

This study provides more data for understanding the relation among LCR mutations, lineages and carcinogenesis. It also helps performing further study to demonstrate biological function of LCR and find potential marker for diagnosis and therapy.

Human Papillomavirus 58 E7 T20I/G63S Variant Isolated from an East Asian Population Possesses High Oncogenicity

Human papillomavirus (HPV) type 58 is the third most commonly detected HPV type in cervical cancer among Eastern Asians. Our previous international epidemiological studies revealed that HPV58 carrying an E7 natural variant, T20I/G63S (designated V1), was associated with a higher risk of cervical cancer. We recently showed that V1 possesses a greater ability to immortalize and transform primary cells, as well as degrading pRB more effectively, than the prototype and other common variants. In this study, we performed a series of phenotypic and molecular assays using physiologically relevant in vitro and in vivo models to compare the oncogenicity of V1 with that of the prototype and other common natural variants. Through activation of the AKT and K-Ras/extracellular signal-regulated kinase (ERK) signaling pathways, V1 consistently showed greater oncogenicity than the prototype and other variants, as demonstrated by increased cell proliferation, migration, and invasion, as well as induction of larger tumors in athymic nude mice. This study complements our previous epidemiological and molecular observations pinpointing the higher oncogenicity of V1 than that of the prototype and all other common variants. Since V1 is more commonly found in eastern Asia, our report provides insight into the design of HPV screening assays and selection of components for HPV vaccines in this region.IMPORTANCE Epidemiological studies have revealed that a wild-type variant of HPV58 carrying an E7 variation, T20I/G63S (V1), is associated with a higher risk of cervical cancer. We previously reported that this increased oncogenicity could be the result of the virus's greater ability to degrade pRB, thereby leading to an increased ability to grow in an anchorage-independent manner. In addition to this, this report further showed that this HPV variant induced activation of the AKT and K-Ras/ERK signaling pathways, thereby explaining its genuine oncogenicity in promoting cell proliferation, migration, invasion, and formation of tumors, all to a greater extent than the prototype HPV58 and other common variants.

Efficacy, Immunogenicity, and Safety of a 9-Valent Human Papillomavirus Vaccine: Subgroup Analysis of Participants From Asian Countries

Background

A 9-valent human papillomavirus-6/11/16/18/31/33/45/52/58 (9vHPV) vaccine extends coverage to 5 next most common oncogenic types (31/33/45/52/58) in cervical cancer versus quadrivalent HPV (qHPV) vaccine. We describe efficacy, immunogenicity, and safety in Asian participants (India, Hong Kong, South Korea, Japan, Taiwan, and Thailand) from 2 international studies: a randomized, double-blinded, qHPV vaccine-controlled efficacy study (young women aged 16–26 years; NCT00543543; Study 001); and an immunogenicity study (girls and boys aged 9–15 years; NCT00943722; Study 002).

Methods

Participants (N = 2519) were vaccinated at day 1 and months 2 and 6. Gynecological samples (Study 001 only) and serum were collected for HPV DNA and antibody assessments, respectively. Injection-site and systemic adverse events (AEs) were monitored. Data were analyzed by country and vaccination group.

Results

9vHPV vaccine prevented HPV-31/33/45/52/58–related persistent infection with 90.4%–100% efficacy across included countries. At month 7, ≥97.9% of participants seroconverted for each HPV type. Injection-site AEs occurred in 77.7%–83.1% and 81.9%–87.5% of qHPV and 9vHPV vaccine recipients in Study 001, respectively, and 62.4%–85.7% of girls/boys in Study 002; most were mild to moderate.

Conclusions

The 9vHPV vaccine is efficacious, immunogenic, and well tolerated in Asian participants. Data support 9vHPV vaccination programs in Asia.

Clinical Trials Registration

NCT00543543; NCT00943722.

Role of genomic DNA methylation in detection of cytologic and histologic abnormalities in high risk HPV-infected women

Cervical cancer is the fourth most common malignancy affecting women worldwide. The development of disease is related to high-risk human papillomavirus (hrHPV) infection. Cytology has been the most recommended triage for primary cervical (pre)cancer screening despite relatively low sensitivity. Recently, genomic DNA methylation has been proposed as an additional marker to increase sensitivity for detecting cervical precancerous lesion. This study aimed to evaluate the performance of methylation status of three tumor suppressor genes (CADM1, FAM19A4, and MAL) and HPV genotyping in detection of cytologic and histologic abnormalities in cervical cancer screening. Two hundred and sixty samples with available frozen cell pellets including 70 randomly selected cases of negative for intraepithelial lesion or malignancy (NILM)&HPV-negative, 70 randomly selected cases of NILM&HPV-positive, and 120 cytologic abnormalities & HPV-positive from a population-based cervical cancer screening program (n = 7,604) were investigated for the DNA methylation pattern of CADM1, FAM19A4, and MAL. Of 120 cytologic abnormalities & HPV-positive cases, there were 115 available histologic results. HPV52 and HPV58 were most commonly found in histologic HSIL+. The methylation levels of CADM1, FAM19A4, and MAL were elevated with the severity of cytologic abnormality which significantly increased by 3.37, 6.65 and 2 folds, respectively, in cytologic HSIL comparing with NILM. A significant increase in methylation levels of these three genes was also observed in histologic HSIL+ compared with negative histology but only CADM1 showed a significant higher methylation level than histologic LSIL. Using the ROC curve analysis, DNA methylation levels of FAM19A4 performed best in differentiating high-grade cytology (ASC-H+ from NILM/ASC-US/LSIL), followed by CADM1 and MAL. Whilst the CADM1 methylation performed best in distinguishing histologic HSIL+ from negative/LSIL with an area under the ROC curve of 0.684, followed by MAL (0.663) and FAM19A4 (0.642). Interestingly, after combining high DNA methylation levels to HPV16/18 genotypes, rates of histologic HSIL+ detection were substantially increased from 25% to 79.55% for CADM1, 77.27% for FAM19A4, and 72.73% for MAL, respectively. The rate further increased up to 95.45% when at least one of three genes had a high methylation level. This suggests a possible role of genomic DNA methylation, especially CADM1, in detecting histologic HSIL+ lesions in combination with hrHPV testing.

Oncogenic comparison of human papillomavirus type 58 E7 variants

Human papillomavirus 58 (HPV58) ranks the second or third in East Asian cervical cancers. Current studies on HPV58 are scarce and focus on the prototype. Previously, we identified the three most common circulating HPV58 E7 strains contained amino acid alterations: G41R/G63D (51%), T20I/G63S (22%) and T74A/D76E (14%) respectively. Among them, the T20I/G63S variant (V1) had a stronger epidemiological association with cervical cancer. We therefore suggested that V1 possessed stronger oncogenicity than the other two variants. Here, we performed phenotypic assays to characterize and compare their oncogenicities with HPV58 E7 prototype. Our results showed that overexpression of V1 conferred a higher colony-forming ability to primary murine epithelial cells than prototype (P < 0.05) and other variants, implicating its higher immortalising potential. Further experiments showed that both V1 and prototype enhanced the anchorage-independent growth of NIH/3T3 cells (P < 0.001), implicating their stronger transforming power than the two other variants. Moreover, they possessed an increased ability to degrade pRb (P < 0.001), which is a major effector pathway of E7-driven oncogenesis. Our work represents the first study to compare the oncogenicities of HPV58 E7 prototype and variants. These findings deepened our understanding of HPV58 and might inform clinical screening and follow-up strategy.

Simultaneously characterizing the comparative economics of routine female adolescent nonavalent human papillomavirus (HPV) vaccination and assortativity of sexual mixing in Hong Kong Chinese: a modeling analysis

BACKGROUND

Although routine vaccination of females before sexual debut against human papillomavirus (HPV) has been found to be cost-effective around the world, its cost-benefit has rarely been examined. We evaluate both the cost-effectiveness and cost-benefit of routine female adolescent nonavalent HPV vaccination in Hong Kong to guide its policy, and by extension that of mainland China, on HPV vaccination. One major obstacle is the lack of data on assortativity of sexual mixing. Such difficulty could be overcome by inferring sexual mixing parameters from HPV epidemiologic data.

METHODS

We use an age-structured transmission model coupled with stochastic individual-based simulations to estimate the health and economic impact of routine nonavalent HPV vaccination for girls at age 12 on cervical cancer burden and consider vaccine uptake at 25%, 50%, and 75% with at least 20 years of vaccine protection. Bayesian inference was employed to parameterize the model using local data on HPV prevalence and cervical cancer incidence. We use the human capital approach in the cost-benefit analysis (CBA) and GDP per capita as the indicative willingness-to-pay threshold in the cost-effectiveness analysis (CEA). Finally, we estimate the threshold vaccine cost (TVC), which is the maximum cost for fully vaccinating one girl at which routine female adolescent nonavalent HPV vaccination is cost-beneficial or cost-effective.

RESULTS

As vaccine uptake increased, TVC decreased (i.e., economically more stringent) in the CBA but increased in the CEA. When vaccine uptake was 75% and the vaccine provided only 20 years of protection, the TVC was US$444 ($373-506) and $689 ($646-734) in the CBA and CEA, respectively, increasing by approximately 2-4% if vaccine protection was assumed lifelong. TVC is likely to be far higher when non-cervical diseases are included. The inferred sexual mixing parameters suggest that sexual mixing in Hong Kong is highly assortative by both age and sexual activity level.

CONCLUSIONS

Routine HPV vaccination of 12-year-old females is highly likely to be cost-beneficial and cost-effective in Hong Kong. Inference of sexual mixing parameters from epidemiologic data of prevalent sexually transmitted diseases (i.e., HPV, chlamydia, etc.) is a potentially fruitful but largely untapped methodology for understanding sexual behaviors in the population.

The role of human papillomavirus in laryngeal cancer in Southern China

To delineate the role of human papillomavirus (HPV) in laryngeal cancer in Southern Chinese, a retrospective cross-sectional study was conducted in a major otorhinolaryngology referral center in Hong Kong. Eighty-five Chinese patients with histology-confirmed laryngeal squamous cell carcinoma (LSCC) diagnosed between 2005 and 2010 were examined for the status of HPV by PCR, and the expression of p16 and p53 by immunohistochemistry. The HPV, p16 and p53 findings were correlated with clinicopathological features, recurrence and 5-year survival. HPV DNA was detected in one patient (1.2%, 95%CI: 0.2-6.4%) who had glottic cancer and harbored HPV-6. Overexpression of p16 and p53 were detected in 11 (12.9%) and 47 (55.3%) cases, respectively. Recurrence occurred in 22.4% of patients at a median of 13 months. The 5-year overall survival and disease-specific survival were 55.7% and 72.4%, respectively. Overexpression of p16 or p53 was not associated with clinicopathological features, recurrence or overall survival. HPV plays a limited role in laryngeal cancer in Hong Kong Southern Chinese. In contrast to oropharyngeal cancer, p16 cannot be used as a surrogate marker for oncogenic involvement of HPV and cannot predict survival in laryngeal cancer.

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

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

The variable clinicopathological categories and role of human papillomavirus in cervical adenocarcinoma: A hospital based nation-wide multi-center retrospective study across China

We investigated HPV in adenocarcinoma presenting and managed as cervical adenocarcinoma (CADC) at seven major representative regional cancer centres across China. From 1,051 CADC cases diagnosed locally in 2005-2010, 881 had available paraffin embedded tissue. Initial review excluded 154 cases as other diagnoses or inappropriate specimens. In 718 eligible cases consensus panel pathology diagnosis was made using an algorithm incorporating p16 and progesterone receptor immunohistochemistry (IHC). Classification of cervical adenocarcinoma categories was subject to substantial pathological disagreement. High-risk human papillomaviruses (HR-HPV) DNA was studied by the sensitive SPF10 PCR-DEIA-LiPA25 version 1 for L1 genes and type-specific HR-HPV E6/7 gene PCR's. HR-HPV prevalence in whole tissue samples in eligible tested CADC was 74.5%: 100.0% in neuro-endocrine carcinoma (NEC), 82.2% in classical cervical adenocarcinoma (ADC-CX), 40.0% in adenocarcinoma-not otherwise specified (ADC-NOS) and 33.3% in endometrioid adenocarcinoma (ADC-ENDO). Higher mean age at diagnosis correlated with histological categories showing low HPV prevalence (Linear regression: β= -13.794, p < 0.001). HPV-16 and 18 were associated with early development of CADC and a lower mean age correlated with carcinogenic risk of associated HPV (β = -0.1829, p < 0.001). HPV-16 or HPV-18 was found in 88.2% of all HPV positive cases including multiple-infections. HPV-18 was the commonest HPV type in NEC (58.3%), ASC (40.2%) and ADC-CX (40.9%). The proportion of HPV-unrelated CADC and in different final histological categories varied geographically and by age. Although HPV negativity was predominantly associated with special categories of CADC, some HPV-negative usual adenocarcinomas indistinguishable by adjudicated microscopic diagnosis from ADC-CX were found and varied in frequency across China.

Association between human papillomavirus type 16 E6 and E7 variants with subsequent persistent infection and recurrence of cervical high-grade squamous intraepithelial lesion after conization

The study aimed to detect the variants of human papillomavirus (HPV) type 16 E6 and E7 in patients with cervical high-grade squamous intraepithelial lesion (HSIL), and to determine the existence and recurrence of persistent infection after treatment with loop electrosurgical excision procedure (LEEP). Preoperatively collected cervical exfoliated cells from 100 HPV 16 positive HSIL patients enrolled in the study were used to test for E6 and E7 variants. Follow-ups which included TCT, HPV test, and colposcopy were performed every 3 months after the operation, and colposcopic biopsy and endocervical curettage were performed for patients with abnormalities. Patients were followed for 2 years, and recurrence was defined as detecting low-grade squamous intraepithelial lesion (LSIL) or relapse of HSIL in 1 year. In 81% of patients, the E6 variant was the Asian prototype (As.P), 14% of patients had the European variant, 2% had the European prototype (EP), and 3% had the African 1 variant (Af1). The HPV16 could be easily cleared by LEEP in patients with As.P. Persistent infection or recurrence was very rare in this group. The patients with European variants T350G or A442C had a significantly higher incidence of persistent and recurring HPV16 infection. In conclusion, (i) in most cases, As.P caused HSIL. (ii) The European variant E6 T350G/A442C may be associated with higher rates of recurring and persistent HPV16 infection after the LEEP. (iii) The E7 gene mutation may not be a risk factor for recurring HSIL caused by HPV16 or persistent infection. J. Med. Virol. 88:1982-1988, 2016. © 2016 Wiley Periodicals, Inc.

Genotype Distribution of Human Papillomavirus among Women with Cervical Cytological Abnormalities or Invasive Squamous Cell Carcinoma in a High-Incidence Area of Esophageal Carcinoma in China

Data of HPV genotype including 16 high-risk HPV (HR-HPV) and 4 low-risk HPV from 38,397 women with normal cytology, 1341 women with cervical cytology abnormalities, and 223 women with ISCC were retrospectively evaluated by a hospital-based study. The prevalence of high-risk HPV (HR-HPV) was 6.51%, 41.83%, and 96.86% in women with normal cytology, cervical cytology abnormalities, and ISCC, respectively. The three most common HPV types were HPV-52 (1.76%), HPV-16 (1.28%), and HPV-58 (0.97%) in women with normal cytology, whereas the most prevalent HPV type was HPV-16 (16.85%), followed by HPV-52 (9.55%) and HPV-58 (7.83%) in women with cervical cytology abnormalities. Specifically, HPV-16 had the highest frequency in ASC-H (24.16%, 36/149) and HSIL (35.71%, 110/308), while HPV-52 was the most common type in ASC-US (8.28%, 53/640) and LSIL (16.80%, 41/244). HPV-16 (75.78%), HPV18 (10.31%), and HPV58 (9.87%) were the most common types in women with ISCC. These data might contribute to increasing the knowledge of HPV epidemiology and providing the guide for vaccine selection for women in Shantou.

Prevalence, Clinicopathological Characteristics, and Outcome of Human Papillomavirus-Associated Oropharyngeal Cancer in Southern Chinese Patients

BACKGROUND

Although the global incidence of human papillomavirus (HPV)-associated oropharyngeal squamous cell carcinoma (OPSCC) is increasing, there is little information on southern Chinese population available.

METHODS

We analyzed 207 patients which constituted 63.5% of all newly diagnosed OPSCC in Hong Kong during a 5-year period from 2005 to 2009.

RESULTS

We used E6/7 mRNA as a marker of oncogenic involvement and found 20.8% (43/207) of OPSCC and 29.0% (36/124) of tonsillar SCC was associated with HPV. HPV-16 was identified in all cases except one (HPV-18). Patients with HPV-associated OPSCCs were significantly younger than HPV-negative patients (mean age: 59.8 vs. 63.9 years, P = 0.05). Multivariate analysis showed that HPV-associated OPSCC was more likely to occur in nonsmokers (39.5% vs. 15.1%, OR: 2.89, P = 0.05), nondrinkers (52.5% vs. 25.6%, OR: 2.72, P = 0.04), originate from the palatine tonsils (83.7% vs. 53.7%, OR: 3.88, P = 0.01), present with an early primary tumor (T1/2; 79.1% vs. 47.6%, OR: 3.81, P = 0.004), and exhibit basaloid differentiation (33.3% vs. 7.3%, OR: 19.74, P = 0.006). HPV positivity was an independent predictor for better prognosis for both 5-year overall and 5-year disease-specific survivals (DSS; 63.0% vs. 29.7%, HR: 0.33, P < 0.001, and 87.8% vs. 42.6%, HR: 0.16, P < 0.001, respectively).

CONCLUSION

The estimated age-standardized incidence of OPSCC in Hong Kong during the period 2005-2009 was 0.12/100,000/year.

IMPACT

This study has provided the most comprehensive clinical and pathologic information to date about this newly recognized disease in southern Chinese. In view of the global trend, we should anticipate and prepare for an increase in HPV-related OPSCC in southern China.

The role of human papillomavirus in head and neck squamous cell carcinoma: A case control study on a southern Chinese population

HPV plays a role in the development of a portion of head and neck squamous cell carcinoma (HNSCC), but only limited information on its role in southern Chinese population is available. A multicenter case-control study was conducted. HPV type, viral integration, E6/7 mRNA expression status, and TP53 mutation were determined. A total of 228 HNSCC were recruited including 137 (60.1%) oral SCC, 34 (14.9%) oropharyngeal SCC, 31 (13.6%) laryngeal SCC, 21 (9.2%) hypopharyngeal SCC, and 5 (2.2%) lip and paranasal sinus SCC. High-risk HPV infection was found in 7.5% (17/228) of HNSCC, but only a small proportion of samples had evidence of viral integration (5.3%, 12/228) or E6/7 mRNA expression (4.4%, 10/228). HPV infection with oncogenic phenotype (integration and E6/7 mRNA expression) was significantly more common in oropharyngeal SCC than controls (9/34, 26.5% vs. 0/42, 0.0%, P < 0.001). Smoking showed a significant association with HNSCC, oropharyngeal SCC, and laryngeal SCC. TP53 mutation was associated with HNSCC (P < 0.001). Older age, TP53 mutation, and HPV16 infection with oncogenic phenotypes were independently associated factors for HNSCC with odds ratios of 1.03 (1.02-1.05), 3.38 (1.71-6.66), and 9.19 (1.13-74.68), respectively. High-risk HPV infection of head and neck mucosa is not uncommon in the Hong Kong population. This study found that 26-30% of oropharyngeal carcinoma was associated with HPV infection, mostly HPV16, and that smoking which predisposes to TP53 mutations was another important risk factor.

Prognostic implication of human papillomavirus types and species in cervical cancer patients undergoing primary treatment

High-risk human papillomavirus (HPV) types are associated with cervical cancer. It is well established that individual HPV types vary in oncogenicity, but current data on their prognostic implication remain controversial. We examined the association between HPV types/species and the survival of 236 Chinese women aged 26–87 (mean 54.4) years after receiving primary treatment for cervical cancer. Overall, 45.8% were of FIGO stage I, 41.9% stage II, and 12.3% stage III. The four most prevalent types found were HPV-16 (60.2%), HPV-18 (21.6%), HPV-52 (11.9%), and HPV-58 (9.3%). Overall, 19.5% of patients had multiple-type infections, 78.4% harboured one or more alpha-9 species, and 28.8% harboured one or more alpha-7 species. After a median follow-up of 8.0 years, 156 (66.1%) patients survived. The 3-year overall survival rate was 75.5%. Factors independently associated with a poorer 3-year overall survival were age >60 years, tumour size >4 cm, lymph node involvement and treatment with radiotherapy+/-chemotherapy. Univariate analysis showed HPV-16 single-type infection was associated with a marginally poorer disease-specific survival (71.6% vs. 87.0%, HR: 1.71, 95% CI = 1.01–2.90), whereas non-HPV-16 alpha-9 species was associated with a better disease-specific survival (90.0% vs. 76.2%, HR: 0.36, 95% CI = 0.16–0.79). However, on multivariate analysis, HPV infection status irrespective of different grouping methods, including individual types, species, single-type or co-infection, did not carry any significant prognostic significance. In conclusion, we did not observe any association between infection with a particular HPV type/species and survival. An HPV type-based stratification in treatment and follow-up plan could not be recommended.

Association of human papillomavirus type 58 with breast cancer in Shaanxi province of China

A number of reports have identified HPV DNA in breast cancer specimens and HPV type 16, 18, 31, 33, 45, and 51 were more prevalent. HPV 58 was frequently detected in cervical cancer in Shaanxi China. The aim of the present study was to investigate whether HPV 58 present in breast cancer. 169 cases of breast cancer samples and 83 benign breast lesions were analyzed. Type specific primers and oligonucliotide probe were used for the detection of HPV 58 by conventional PCR and in situ hybridization techniques. The HPV 58 viral load were measured by qPCR. p16 protein expression were evaluated by immunohistochemistry. HPV 58 E7 DNA was detected in 25 out of 169 formalin fixed paraffin embedded breast cancer tissues (14.79%) by PCR, only 1 out of 83 non-malignant breast lesions showed positive (1.20%). The results of ISH showed that 17 out of 169 (10.06%) malignant samples were positive for HPV 58 E7, and only 1 out of 83 non-malignant lesions was positive. Positive p16 immunostaining was observed in all the HPV 58 E7 ISH positive cases, but 16 out of 98 cases with HPV negative were p16 positive. The presence of HPV 58 in both normal duct epithelial cells and carcinoma in situ along with its presence in the cancer cells of the same specimen indicated the possible causal role of HPV 58 in breast cancer. The findings provide a solid morphological evidence of the involvement of HPV 58 in breast cancer development.

Distribution of high-risk human papillomavirus genotypes in HPV-infected women in Beijing, China

To investigate the distribution of high-risk human papillomavirus (HPV) genotypes in infected women from Beijing, China, samples were obtained during routine gynecologic examinations and DNA was extracted from the samples, and PCR was performed to distinguish the 13 high-risk HPV subtypes (16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, and 68). Samples were obtained from 1160 women (20-75 years old), and 470 cases of high-risk HPV infection were diagnosed. HPV 52, HPV 16, HPV 58, HPV 51, and HPV 39 were the most common genotypes accounting for 22.8%, 22.3%, 20.0%, 14.3%, and 13.6% of cases, respectively. The highest infection rates were found in 20-30 year-old patients (35.1%). HPV 16 infection was the highest in the 31-40 year-old group, and HPV 52, HPV 58, and HPV 39 infections were highest in the 20-30 year-old group. Some patients were infected with multiple high-risk HPV subtypes. Of the 470 patients with positive HPV tests, 65.7% of women were infected with a single high-risk HPV subtype, 23.2%, of women were infected with two high-risk HPV subtypes, 7.7% were infected with three subtypes, and 3.4% of women were infected with more than three high-risk HPV subtypes. In this study, HPV 16 and HPV 52 were the most common subtypes found in patients with cervical lesions.

Meta-analysis on prevalence and attribution of human papillomavirus types 52 and 58 in cervical neoplasia worldwide

Objective

To estimate the prevalence and attribution of two non-vaccine-covered HPV types (HPV52 and HPV58) across the world.

Methods

Meta-analysis on studies reported in English and Chinese between 1994 and 2012.

Results

The pooled prevalence and attribution rates of HPV52 and HPV58 in invasive cervical cancers were significantly higher in Eastern Asia compared to other regions (HPV52 prevalence: 5.7% vs. 1.8–3.6%, P<0.001; HPV52 attribution: 3.7% vs. 0.2–2.0%; HPV58 prevalence: 9.8% vs. 1.1–2.5%, P<0.001; HPV58 attribution: 6.4% vs. 0.7–2.2%, P<0.001). Oceania has an insufficient number of studies to ascertain the prevalence of HPV52. Within Eastern Asia, the attribution of HPV58 to invasive cervical cancer was 1.8-fold higher than that of HPV52. Similarly, HPV52 and HPV58 shared a higher prevalence and attribution among cervical intraepithelial neoplasia in Eastern Asia. In contrast to the classical high-risk type, HPV16, the prevalence and attribution of HPV52 and HPV58 decreased with increasing lesion severity. Thus, HPV52 and HPV58 behave as an “intermediate-risk” type.

Conclusion

The attribution of HPV52 and HPV58 to cervical intraepithelial neoplasia and invasive cancer in Eastern Asia were respectively 2.5–2.8 and 3.7–4.9 folds higher than elsewhere. Changes in the attributed disease fraction can serve as a surrogate marker for cross-protection or type replacement following widespread use of HPV16/18-based vaccines. This unique epidemiology should be considered when designing HPV screening assays and vaccines for Eastern Asia.

Genotype-specific prevalence and distribution of human papillomavirus genotypes in underserved Latino women with abnormal Papanicolaou tests

INTRODUCTION

Knowledge about the prevalence and distribution of human papillomavirus (HPV) genotypes in cervical premalignant and malignant lesions is crucial to guide development of clinical management strategies and prophylactic vaccines. The aim of this study was to determine HPV genotype-specific prevalence and distribution in an underserved cohort of Latino women.

MATERIALS AND METHODS

From December 2009 to April 2011, 808 SurePath cervicovaginal specimens were collected from women who were referred from charity clinics for abnormal Papanicolaou tests. The patients' average age was 36.5 years (range 19-85 years). The specimens were tested for HPV genotypes by DNA microarray and sequencing assays.

RESULTS

The HPV infection rate was extremely high (93% for any HPV and 64% for high-risk [HR]-HPV), with frequent multiple-strain infection (39%). Younger age (<30 years) was associated with frequent HR-HPV infection, multiple strain infections, and cytologic abnormalities. When compared with previous reports, HPV 16 remained the most common genotype (44.6%) in women with high-grade squamous intraepithelial lesion; however, a significant increase in HPV 31 (17.9%) and 45 (10.7%) and a decrease in HPV 35, 52, 33, and 66 were observed.

CONCLUSIONS

The HPV genotype-specific prevalence and distribution pattern in this cohort of underserved Latino women differed significantly from previously published data in the United States. Understanding the potentially changing trends in HPV distribution pattern will help guide the development of appropriate preventive and therapeutic strategies for both underserved and general populations.

Quadrivalent HPV vaccine efficacy against disease related to vaccine and non-vaccine HPV types in males

A small number of HPV types are related to a majority of HPV-related neoplastic lesions in humans. High-risk types such as HPV 16 and 18 are most often implicated, although other oncogenic and non-oncogenic HPV types can cause disease in men. The efficacy of the quadrivalent HPV vaccine (qHPV) against external genital lesions and intra-anal disease related to HPV in men has been demonstrated. This report examines the vaccine's efficacy against disease due to 10 additional non-vaccine HPV types, as well as efficacy regardless of HPV detection. The data presented suggest that vaccinating males against HPV 6, 11, 16 and 18 protects them against most vaccine HPV-type related anogenital disease. However, significant efficacy against disease due to non-vaccine HPV types was not seen. In addition, the data do not provide any evidence that vaccination with qHPV vaccine will increase the likelihood of disease caused by non-vaccine types in the short term.

Significance of HPV-58 infection in women who are HPV-positive, cytology-negative and living in a country with a high prevalence of HPV-58 infection

Purpose

Cervical cytology and human papillomavirus (HPV) DNA co-testing is recommended as a screening method for detecting cervical lesions. However, for women who are HPV-positive but cytology-negative, the appropriate management and significance of HPV-58 infection remain unknown.

Methods

This study of prevalent HPV detected at baseline with a median follow-up of 3.2 years evaluated the risk factors associated with cervical abnormalities and assessed the significance of HPV-58 infection. A total of 265 women were enrolled. All high-grade squamous intraepithelial lesions (HSIL) that were detected by cytology were confirmed by histology. Histological diagnoses of cervical intraepithelial neoplasia 2/3 were classified as HSIL. Women were classified into four groups according to the HPV genotype that was detected at their first visit: HPV-58 (n = 27), HPV-16 (n = 52; 3 women had HPV-58 co-infection), ten other high risk (HR) types (n = 79), or low/undetermined risk types (n = 107).

Results

Of 265 women, 20 (7.5%) had HSIL on their follow-up examinations. There were significant differences in the cumulative incidence of HSIL between the four groups (p<0.001). The 5-year cumulative incidence rates of HSIL were 34.0% (95% CI: 17.3–59.8%) in HPV-58 positive cases, 28.0% (95% CI: 13.8–51.6) in HPV-16 positive cases, 5.5% (95% CI: 2.1–14.0%) in one of the ten other types of HR-HPV positive cases, and 0% in women with low/undetermined risk HPV. When seen in women with HR-HPV (n = 158), persistent HPV infection was a significant factor associated with the development of HSIL (hazard ratio = 15.459, 95% CI: 2.042–117.045). Women with HPV-58 had a higher risk (hazard ratio = 5.260, 95% CI: 1.538–17.987) for the development of HSIL than women with HPV-16 (hazard ratio = 3.822, 95% CI: 1.176–12.424) in comparison with women with other types of HR-HPV.

Conclusion

HPV-58 has a high association with the development of HSIL in women who are HPV-positive and cytology-negative.

Geographical distribution and oncogenic risk association of human papillomavirus type 58 E6 and E7 sequence variations

Human papillomavirus (HPV) 58 accounts for a notable proportion of cervical cancers in East Asia and parts of Latin America, but it is uncommon elsewhere. The reason for such ethnogeographical predilection is unknown. In our study, nucleotide sequences of E6 and E7 genes of 401 HPV58 isolates collected from 15 countries/cities across four continents were examined. Phylogenetic relationship, geographical distribution and risk association of nucleotide sequence variations were analyzed. We found that the E6 genes of HPV58 variants were more conserved than E7. Thus, E6 is a more appropriate target for type-specific detection, whereas E7 is more appropriate for strain differentiation. The frequency of sequence variation varied geographically. Africa had significantly more isolates with E6-367A (D86E) but significantly less isolates with E6-203G, -245G, -367C (prototype-like) than other regions (p ≤ 0.003). E7-632T, -760A (T20I, G63S) was more frequently found in Asia, and E7-793G (T74A) was more frequent in Africa (p < 0.001). Variants with T20I and G63S substitutions at E7 conferred a significantly higher risk for cervical intraepithelial neoplasia grade III and invasive cervical cancer compared to other HPV58 variants (odds ratio = 4.44, p = 0.007). In conclusion, T20I and/or G63S substitution(s) at E7 of HPV58 is/are associated with a higher risk for cervical neoplasia. These substitutions are more commonly found in Asia and the Americas, which may account for the higher disease attribution of HPV58 in these areas.

Clinical implications of human papillomavirus genotype in cervical adeno-adenosquamous carcinoma

BACKGROUND

Our aims were to evaluate the genotype distribution of human papillomavirus (HPV) and the correlation between HPV parameters and clinicopathological/treatment variables with prognosis in cervical adeno-adenosquamous carcinoma (AD/ASC).

PATIENTS AND METHODS

Consecutive patients who received primary treatment for cervical AD/ASC International Federation of Gynecology and Obstetrics (FIGO) stages I-IV between 1993 and 2008 were retrospectively reviewed. Prognostic models were constructed and followed by internal validation with bootstrap resampling.

RESULTS

A total of 456 AD/ASC patients were eligible for HPV genotyping, while 452 were eligible for survival analysis. HPV18 was detected in 51.5% and HPV16 in 36.2% of the samples. Age >50 years old, FIGO stages III-IV and HPV16-negativity were significantly related to cancer relapse, and age >50, FIGO stages III-IV, HPV16-negativity and HPV58-positivity were significant predictors for cancer-specific survival (CSS) by multivariate analyses. HPV16-positivity was also significantly associated with good prognosis in those receiving primary radiotherapy or concurrent chemoradiation (RT/CCRT) (CSS: hazard ratio 0.41, 95% confidence interval 0.21-0.78). Patients with FIGO stages I-II and HPV16-negative AD/ASC treated with primary RH-PLND had significantly better CSS (p<0.0001) than those treated with RT/CCRT.

CONCLUSIONS

Age >50 years old, FIGO stages III-IV and HPV16-negativity were significant poor prognostic factors in cervical AD/ASC. Patients with HPV16-negative tumour might better be treated with primary surgery (e.g. radical hysterectomy for stages I-II and pelvic exenteration for stage IVA). Those with unresectable HPV16-negative tumour (stage IIIB) should undergo CCRT in combination with novel drugs. The inferences of a single-institutional retrospective study require prospective studies to confirm.

T-cell response to human papillomavirus type 52 L1, E6, and E7 peptides in women with transient infection, cervical intraepithelial neoplasia, and invasive cancer

The E6 and E7 proteins encoded by human papillomaviruses (HPV) are prime targets for therapeutic vaccine development. Ninety-five women with HPV 52 infection (33 transient infections, 17 cervical intraepithelial neoplasia grade II, 15 cervical intraepithelial neoplasia grade III, and 30 invasive cervical cancers) were examined for T-cell responses using interferon-γ enzyme-linked immunospot (IFN-γ ELISPOT) assay. Of the 29 peptides (13 L1, 10 E6, and 6 E7) screened positive by an in vitro peptide-binding assay, 14 were positive by the IFN-γ ELISPOT assay. Positive epitopes for HLA A11 were located at amino acid positions 103-111, 332-340, 342-350, and 373-381 of the L1 protein; and at 27-35 and 86-94 of the E6 protein; and at 1-9 and 27-35 of the E7 protein. A24-specific epitopes included 60-68 and 98-106 of the L1 protein, 42-50 and 59-67 of the E6 protein, and 24-32 of the E7 protein. Only one epitope (99-107) of the E6 protein showed positive responses for HLA A2 subjects. Overall, T-cell responses against L1 were observed mainly in subjects who had cleared infection; whereas responses against E6 and E7 were confined mainly to subjects who had developed cervical neoplasia. The proportion of subjects showing detectable T-cell responses was low across all grades of cervical neoplasia suggesting that immune evasion mechanisms had set on early in the course of disease progression. This study provides the first set of T-cell epitopes mapped for HPV 52, which can be considered for further evaluation as targets for immunotherapy.

Laboratory and clinical aspects of human papillomavirus testing

Human papillomavirus (HPV) infection is associated with a wide spectrum of disease that ranges from self-limited skin warts to life-threatening cancers. Since HPV plays a necessary etiological role in cervical cancer, it is logical to use HPV as a marker for early detection of cervical cancer and precancer. Recent advances in technology enable the development of high-throughput HPV assays of different formats, including DNA-based, mRNA-based, high-risk group-specific and type-specific methods. The ultimate goal of these assays is to improve the accuracy and cost-effectiveness of cervical screening programs. HPV testing has several potential advantages compared to cytology-based screening. However, since the cancer to transient infection ratio is always low in the general population, HPV test results are bound to have a low positive predictive value that may subject women to unnecessary follow-up investigations. The wide-spread administration of prophylactic HPV vaccine will substantially decrease the incidence of cancer and precancer. This poses a number of challenges to cytology-based screening, and the role of HPV testing is expected to increase. Finally, apart from technical and cost-effectiveness considerations, one should also keep in mind the psycho-social impact of using sexually-transmitted agents as a marker for cancer screening.

Human papillomavirus type 58: the unique role in cervical cancers in East Asia

Background

About 15 types of human papillomavirus (HPV) are classified as high-risk based on their epidemiological link with cervical cancer. These HPV types have deferent degrees of oncogenicity and their distribution among cervical precancers and cancers varies ethnogeographically. HPV58 is rare worldwide but being found more commonly in East Asia.

Findings

A high prevalence of HPV58 among squamous cell carcinoma has been reported from China (28% in Shanghai, 10% in Hong Kong and 10% in Taiwan) and other countries in East Asia including Korea (16%) and Japan (8%). HPV58 ranks the third in Asia overall, but contributes to only 3.3% of cervical cancers globally. The reasons for a difference in disease attribution may lie on the host as well as the virus itself. HLA-DQB1*06 was found to associate with a higher risk of developing HPV58-positive cervical neoplasia in Hong Kong women, but not neoplasia caused by other HPV types. An HPV58 variant (E7 T20I, G63S) commonly detected in Hong Kong was found to confer a 6.9-fold higher risk of developing cervical cancer compared to other variants. A study involving 15 countries/cities has shown a predilection in the distribution of HPV58 variant lineages. Sublineage A1, the prototype derived from a cancer patient in Japan, was rare worldwide except in Asia.

Conclusions

HPV58 accounts for a larger share of disease burden in East Asia, which may be a result of differences in host genetics as well as the oncogenicity of circulating variants. These unique characteristics of HPV58 should be considered in the development of next generation vaccines and diagnostic assays.

Type-specific interaction between human papillomavirus type 58 E2 protein and E7 protein inhibits E7-mediated oncogenicity

Human papillomavirus type 58 (HPV-58) is a very common HPV type in eastern Asia. Little is known about its biology and tumorigenesis. In this study, HPV-58 E2 protein (58E2) was found to interact with E7 protein (58E7), and the hinge domain of 58E2 was shown to be responsible for binding to the 58E7 protein. Interestingly, the E2-E7 interaction appears to be HPV type-specific, as we found that the HPV-16 E2 could not bind to the 58E7 protein, and neither did 58E2 interact with HPV-16 E7. The biological consequence(s) of the E2-E7 interaction in HPV-58, especially in viral tumorigenesis, was investigated. Results showed that, through interacting with 58E7, 58E2 prevented E7-induced retinoblastoma protein (pRb) degradation and prolonged the half-life of pRb in cells. Additionally, 58E2 abrogated 58E7-induced cell proliferation. These observations collectively suggest that direct interaction with 58E7 is another mechanism for 58E2 to inhibit 58E7-associated carcinogenesis in addition to regulating expression of the 58E7 gene.

Comparison of the GenoFlow human papillomavirus (HPV) test and the Linear Array assay for HPV screening in an Asian population

High-risk human papillomavirus (HR-HPV) DNA detection in cervical cytology samples is useful for primary screening of cervical cancer and for triage of patients with equivocal cytological findings. The GenoFlow HPV array test (GF assay; Diagcor Bioscience Inc., Hong Kong) was recently developed to detect 33 HPV genotypes by a "flowthrough" hybridization technology. In this study, we assessed the analytical sensitivity and reproducibility of the GF assay and compared its genotyping results with those of the Linear Array (LA) assay (Roche Molecular Diagnostics, Indianapolis, IN), using 400 archived liquid-based cytology samples representing the full range of cytology findings. Genotyping findings of the GF and LA assays were concordant or compatible for 93.44% of tested samples, with a good (κ = 0.797) to very good (κ = 0.812) strength of agreement for assay-common and oncogenic HPV types, respectively. The two assays showed good (κ = 0.635) agreement in detecting infections with multiple HPV genotypes. The lowest detection limits of the GF assay for HPV16 and HPV18 were 25 copies and 20 copies, respectively. Repeat testing of 60 samples by use of two different lots of the GF assay revealed no discordant results, suggesting good reproducibility of the assay. Both assays achieved approximately 80% and 100% sensitivity for identifying cases of atypical squamous cells of undetermined significance (ASC-US) and low-grade squamous intraepithelial lesions (LSIL) with subsequent detection of LSIL+ and high-grade squamous intraepithelial lesions or higher (HSIL+) in 2 years, respectively. Among ASC-US samples, the GF assay achieved the highest specificity (23.08%) for indicating subsequent identification of HSIL compared with the LA (19.23%) and Hybrid Capture 2 (HC2) (8.97%) assays. The GF and LA assays showed significant discrepancy in detecting HPV genotypes 11, 26, 39, 52, and 66. More sensitive detection of HPV52 by GF assay offers an advantage in regions where HPV52 is more prevalent. The sensitivity of the GF assay for detecting patients with HSIL+ was noninferior to that of the LA assay.

Human papillomavirus type-specific prevalence in women with cervical intraepithelial neoplasm in Western China

Human papillomavirus (HPV) type-specific prevalence was studied in 600 cases of cervical intraepithelial neoplasm in western China by GenoArray test. HPV-16 and -58 were the most prevalent types, with prevalences of 37.8% and 21.8%, respectively. HPV-18 and -45 were uncommon types. The results show different type distributions from that of other regions, which is important evidence for the selection of future genotypes in HPV vaccines in western China.

Identification of human papillomavirus type 58 lineages and the distribution worldwide

BACKGROUND

Human papillomavirus type 58 (HPV-58) accounts for a much higher proportion of cervical cancers in East Asia than other types. A classification system of HPV-58, which is essential for molecular epidemiological study, is lacking.

METHODS AND RESULTS

This study analyzed the sequences of 401 isolates collected from 15 countries and cities. The 268 unique concatenated E6-E7-E2-E5-L1-LCR sequences that comprised 57% of the whole HPV-58 genome showed 4 distinct clusters. L1 and LCR produced tree topologies that best resembled the concatenated sequences and thus are the most appropriate surrogate regions for lineage classification. Moreover, short fragments from L1 (nucleotides 6014-6539) and LCR (nucleotides 7257-7429 and 7540-52) were found to contain sequence signatures informative for lineage identification. Lineage A was the most prevalent lineage across all regions. Lineage C was more frequent in Africa than elsewhere, whereas lineage D was more prevalent in Africa than in Asia. Among lineage A variants, sublineage A2 dominated in Africa, the Americas, and Europe, but not in Asia. Sublineage A1, which represents the prototype that originated from a patient with cancer, was rare worldwide except in Asia.

CONCLUSIONS

HPV-58 can be classified into 4 lineages that show some degree of ethnogeographic predilection in distribution. The evolutionary, epidemiological, and pathological characteristics of these lineages warrant further study.

Construction of a full transcription map of human papillomavirus type 18 during productive viral infection

Human papillomavirus type 18 (HPV18) is the second most common oncogenic HPV genotype, responsible for ∼15% of cervical cancers worldwide. In this study, we constructed a full HPV18 transcription map using HPV18-infected raft tissues derived from primary human vaginal or foreskin keratinocytes. By using 5' rapid amplification of cDNA ends (RACE), we mapped two HPV18 transcription start sites (TSS) for early transcripts at nucleotide (nt) 55 and nt 102 and the HPV18 late TSS frequently at nt 811, 765, or 829 within the E7 open reading frame (ORF) of the virus genome. HPV18 polyadenylation cleavage sites for early and late transcripts were mapped to nt 4270 and mainly to nt 7299 or 7307, respectively, by using 3' RACE. Although all early transcripts were cleaved exclusively at a single cleavage site, HPV18 late transcripts displayed the heterogeneity of 3' ends, with multiple minor cleavage sites for late RNA polyadenylation. HPV18 splice sites/splice junctions for both early and late transcripts were identified by 5' RACE and primer walking techniques. Five 5' splice sites (donor sites) and six 3' splice sites (acceptor sites) that are highly conserved in other papillomaviruses were identified in the HPV18 genome. HPV18 L1 mRNA translates a L1 protein of 507 amino acids (aa), smaller than the 568 aa residues previously predicted. Collectively, a full HPV18 transcription map constructed from this report will lead us to further understand HPV18 gene expression and virus oncogenesis.

Prevalence and genotype distribution of cervical human papillomavirus infection in Macao

Population-specific epidemiological data on human papillomavirus (HPV) infection are essential for formulating strategies to prevent cervical cancer. The age-specific prevalence of HPV infection was determined among 1,600 women enrolled for cervical screening in Macao. A U-shaped age-specific prevalence curve with a first peak (prevalence rate, 10%) at 20-25 years and a second peak (13%) at 51-55 years was observed. Co-infections with multiple types were detected in 32.5% of HPV-positive subjects and without significant variation among different age groups (P = 0.318). The majority (84.6%) of the positive samples harbored high- or probable high-risk HPV types, and these types also exhibited a similar U-shaped age-specific prevalence curve. In contrast, low and unknown-risk HPV types remained at a low prevalence (1.5-2.5%) throughout the age groups between 20 and 50 years, and with a small peak (4.5%) at 51-55 years. HPV 52 was the most common type found in 26.8% of positive samples, followed by HPV 16 (15.5%), HPV 68 (11.4%), HPV 18 and HPV 58 (8.9% each), HPV 54 (8.1%), HPV 53 (7.3%), HPV 39 (6.5%), HPV 33 and HPV 66 (5.7% each). In conclusion, because of the early peak of infection, vaccination and educational campaigns in Macao should start early and target at teenagers. The presence of a second peak containing mainly high-risk HPV types in older women indicates the need to evaluate the cover of the cervical screening programme for older women. Further study to determine the contribution of HPV 52 in high-grade cervical neoplasia and invasive cancers in Macao is warranted.

Distribution of human papillomavirus genotypes among cervical intraepithelial neoplasia and invasive cancers in Macao

Macao is a densely populated city situated in East Asia where a relatively high prevalence of human papillomavirus (HPV) types 52 and 58 has been reported in women with invasive cervical cancer. To provide data for a population-specific estimation on the impact of HPV vaccines, paraffin-embedded tissues collected from women with invasive cervical cancer or cervical intrapeitheilal neoplasia grade 2 or 3 confirmed histologically were examined for HPV using the INNO-LiPa kit. Of the 35 HPV-positive patients with invasive cancer, one HPV type was detected in 68.6%, and 31.4% were co-infected with more than one HPV type. Overall, HPV 16, HPV 18, HPV 52, and HPV 54 were the most common types found respectively in 57.1%, 17%, 11.4%, and 8.5% of patients with invasive cervical cancer. Among the 59 HPV-positive patients with cervical intraepithelial neoplasia grade 2/3, 55.9% hardbored one HPV type, and 44.1% had co-infections. The common HPV types found included HPV 16 (52.5%), HPV 52 (23.7%), HPV 58 (18.7%), and HPV 33 (17%). Although HPV 11 (a low-risk type) was also found commonly in invasive cervical cancers (14.3%) and cervical intraepithelial neoplasia grade 2/3 (15.3%), the fact that they all existed as co-infections with another high-risk type suggested HPV 11 was not the cause of the lesion. The current vaccines targeting HPV 16/18 are expected to cover 62.9-74.3% of invasive cervical cancers and 32.2-55.9% of cervical intraepithelial neoplasia 2/3 in Macao. Widespread HPV vaccination is expected to reduce substantially the disease burden associated with cervical neoplasia in Macao.

Prevalence and genotype distribution of human papillomavirus in women with cervical cancer or high-grade precancerous lesions in Chengdu, western China

OBJECTIVE

To study the prevalence and genotype distribution of human papillomavirus (HPV) among women with cervical cancer or high-grade squamous intraepithelial lesions (HSIL) in western China.

METHODS

Cervical cast-off cells from 144 women with cervical cancer and 63 women with HSIL were tested for HPV genotypes using an oligonucleotide microarray.

RESULTS

The overall HPV prevalence was 80.6% in cases of carcinoma and 61.9% in cases of HSIL. The most common genotypes were HPV-16 (carcinoma, 68.1%; HSIL, 34.9%) and HPV-58 (carcinoma, 8.3%; HSIL, 17.5%). Other high-risk types included HPV-18, -31, -33, -35, -45, and -52, with HPV-18 more common in adenocarcinomas than in squamous cell carcinomas (21.4% vs 3.1%; P<0.02). The HPV prevalence was lower among patients older than 49 years (P<0.02).

CONCLUSION

The prevalence of HPV-16 and HPV-58 was high. This finding may help to improve HPV vaccination and cervical cancer prevention programs in western China.