Burden and Trends of Type-specific Human Papillomavirus Infections and Related diseases in the Asia Pacific Region

Integrative literature review on human papillomavirus vaccination recommendations in national immunization programs in select areas in the Asia-Pacific region

There is limited literature on current human papillomavirus (HPV) vaccination in the Asia-Pacific region. This integrative literature review was conducted to describe HPV vaccination programs in Hong Kong, Indonesia, Japan, South Korea, Malaysia, the Philippines, Singapore, Taiwan, Thailand, and Vietnam. Program descriptions, recommendations, f unding, and coverage data were extracted. Twenty-five citations were included. As of 2022, eight of the 10 areas of interest include HPV in their national immunization program (NIP) for school-aged girls; full implementation in Indonesia is expected in 2023 whereas Vietnam's NIP does not include HPV. Singapore also includes HPV vaccination for women (18-26 years). None of the HPV vaccination programs include males. In most areas (n = 7), programs include only one vaccine option. While female HPV NIPs are present in the Asia-Pacific region, opportunities remain to strengthen NIPs in broader populations (e.g., males, catch-up cohorts) to expand public health impact and provide gender equity in HPV vaccination.

LOC644656 promotes cisplatin resistance in cervical cancer by recruiting ZNF143 and activating the transcription of E6-AP

Cisplatin resistance remains a persistent challenge in cervical cancer (CC) treatment. Molecular biomarkers have garnered attention for their association with cisplatin resistance in various diseases. Long non-coding RNAs (lncRNAs) exert significant influence on CC development. This study explores the role of LOC644656 in regulating cisplatin resistance in CC. Parental and cisplatin-resistant CC cells underwent cisplatin treatment. Functional assays assessed cell proliferation and apoptosis under different conditions. RNA pull-down with mass spectrometry, along with literature review, elucidated the interaction between LOC644656, ZNF143, and E6-AP. Mechanistic assays analyzed the relationship between different factors. RT-qPCR and western blot quantified RNA and protein levels, respectively. In vivo models validated E6-AP's function. Results revealed LOC644656 overexpression in cisplatin-resistant CC cells, exacerbating cell growth. LOC644656 recruited ZNF143 to activate E6-AP transcription, promoting cisplatin resistance in CC. In conclusion, LOC644656 positively modulates E6-AP expression via ZNF143-mediated transcriptional activation, contributing to cisplatin resistance in CC.

The characteristics and risk factors of human papillomavirus infection: an outpatient population-based study in Changsha, Hunan

This cross-sectional study investigated the characteristics of cervical HPV infection in Changsha area and explored the influence of Candida vaginitis on this infection. From 11 August 2017 to 11 September 2018, 12,628 outpatient participants ranged from 19 to 84 years old were enrolled and analyzed. HPV DNA was amplified and tested by HPV GenoArray Test Kit. The vaginal ecology was detected by microscopic and biochemistry examinations. The diagnosis of Candida vaginitis was based on microscopic examination (spores, and/or hypha) and biochemical testing (galactosidase) for vaginal discharge by experts. Statistical analyses were performed using SAS 9.4. Continuous and categorical variables were analyzed by t-tests and by Chi-square tests, respectively. HPV infection risk factors were analyzed using multivariate logistic regression. Of the total number of participants, 1753 were infected with HPV (13.88%). Females aged ≥ 40 to < 50 years constituted the largest population of HPV-infected females (31.26%). The top 5 HPV subtypes affecting this population of 1753 infected females were the following: HPV-52 (28.01%), HPV-58 (14.83%), CP8304 (11.47%), HPV-53 (10.84%), and HPV-39 (9.64%). Age (OR 1.01; 95% CI 1-1.01; P < 0.05) and alcohol consumption (OR 1.30; 95% CI 1.09-1.56; P < 0.01) were found to be risk factors for HPV infection. However, the presence of Candida in the vaginal flora was found to be a protective factor against HPV infection (OR 0.62; 95% CI 0.48-0.8; P < 0.001). Comparing with our previous study of 2016, we conclude that the subtype distribution of HPV infection is relatively constant in Changsha. Our data suggest a negative correlation between vaginal Candida and HPV, however, more radical HPV management is required in this area for perimenopausal women and those who regularly consume alcohol.

Carcinogenic risk of human papillomavirus (HPV) genotypes and potential effects of HPV vaccines in Korea

This study investigated the distribution of HPV types in Korean women and evaluated the carcinogenic risk of individual HPV types and the potential effects of HPV vaccines. A total of 4,081 HPV-positive samples between 2014 and 2017 were included. The most prevalent genotypes were HPV 16, 58, 68, and 56. Among them, HPV 16 was significantly higher in high-grade squamous intraepithelial neoplasia or worse (HSIL+ ) group. In cytologically evaluating the risk for HSIL+ by individual HPV types, HPV 16 was associated with the highest risk of HSIL+ (OR = 10.82; 95% CI: 7.93–14.77), followed by HPV 33, 31, 52, 18, 58, 51, and 35, in descending order (OR = 3.50 [type 33] to 2.62 [type 35]). Among those types, HPV 16, 18, 31, 33, and 58 were also significantly associated with HSIL+ on histologic evaluation. The analysis of the HPV subgroups covered by the different vaccines revealed that the HPV types covered by the 9-valent vaccine had a high association with HSIL+ (OR = 4.09; 95% CI: 3.02–5.54). Our findings highlight the different carcinogenic risks posed by the high risk HPV genotypes and the positive potential effects of the 9-valent HPV vaccine in reducing HPV-associated cervical cancer in Korea.

Incidence, psychosocial burden, and economic impact of genital warts in Mexico

OBJECTIVE

To estimate the burden of genital warts (GW)in Mexico.

MATERIALS AND METHODS

We estimated the annual incidence of GW based on data reported by specialist physicians. We also assessed GW treatment practices, the average cost of treatment, and the psychosocial burden of GW among patients.

RESULTS

The annual incidence of GW in Mexico was estimated to be 547 200 cases. Treatment procedures vary by specialist and patient gender. The estimated annual cost was $195 million USD. The psychosocial impact of GW was slightly greater in males than females.

CONCLUSIONS

This is the first evaluation of the burden of GW in Mexico. Our data suggest that GW are common, with significant health-related costs and psychosocial impact.

Distribution of human papillomavirus genotypes (2014–2016) in women with genital warts at a sexually transmitted disease clinic in Beijing, China

Aim: The aim of this study was to analyze the distribution of human papillomavirus (HPV) genotypes among women with genital warts in the Beijing region of China. Methods: A total of 350 women diagnosed with genital warts between 2014 and 2016 were analyzed by real-time polymerase chain reaction (PCR) to test for high-risk and low-risk HPV subtypes. Results: The results show that 52.6% (184/350) of cases were positive for HPV6+11. The three most common high-risk HPVs detected were HPV52, HPV16 and HPV58, detected in 12.0% (42/350), 10.6% (37/350) and 10.0% (35/350) of all cases, respectively. Conclusion: These results indicate that vaccines targeting HPV subtypes 6, 11, 16, 52 and 58 would have the greatest impact among sexually active women living in Beijing.

Pseudomonas aeruginosa mannose-sensitive hemagglutinin inhibits proliferation and invasion via the PTEN/AKT pathway in HeLa cells

We investigated the effects of Pseudomonas aeruginosa mannose-sensitive hemagglutinin (PA-MSHA) on the proliferation and invasion of human cervical cancer cell lines, as well as the molecular pathways underlying these effects. MTT cell proliferation assays revealed a time- and concentration-dependent cytotoxic effect of PA-MSHA on HeLa cells but not H8 cells. Flow cytometry with propidium iodide and annexin-V-fluorescein isothiocyanate labeling (FITC) indicated that various concentrations of PA-MSHA could induce apoptosis and G2-M cell cycle arrest in HeLa cells. PA-MSHA also impaired the migration and invasion abilities of HeLa cells in Wound healing and Transwell invasion assays. Western blot results demonstrated that PA-MSHA reduced the expression of p-AKT, p-GSK3β, BCL-2, Vimentin and β-catenin, but increased the levels of PTEN, BAD, BAX and E-cadherin in HeLa cells. Importantly, PTEN siRNA induced the activity of p-AKT, while PA-MSHA partly inhibited this induction, indicating that PA-MSHA may reduce the cell proliferation and invasion potential by activating PTEN and thus inhibiting the AKT pathway in vitro. These data suggest the potential application of PA-MSHA to the treatment of human cervical cancer.

Deregulated miRNAs in human cervical cancer: functional importance and potential clinical use

Cervical cancer (CC) is one of the most common malignancies affecting women worldwide. While the morbidity and mortality associated with CC are decreasing in western countries, they both remain high in developing countries. Unfortunately, many issues about molecular mechanisms of CC are not clear yet. miRNAs are a group of small noncoding RNAs that could post-transcriptionally modulate the expression of specific genes and participate in the initiation and progression of multiple diseases including CC. In the last decade, mounting evidences suggest an association between miRNAs and human papillomavirus infection, as well as variations in biologic behavior, treatment response and prognosis in CC. Herein, we highlight the latest findings in this area and the potential applications.

Burden and incidence of human papillomavirus-associated cancers and precancerous lesions in Denmark

Aim: The aim of the study was to investigate the incidence of human papillomavirus (HPV)-associated cancers in Denmark between 1978 and 2011, estimate the current absolute annual number (burden) of HPV-associated cancers (HPVaCa) and their precancerous lesions, and assess whether there is socioeconomic inequality in the risk of HPV-associated cancers. Methods: From four nationwide population-based registries, information was collected on HPVaCa diagnosed during 1978–2011 and age-standardised incidence rate for each site by calendar year and birth cohort was calculated. Furthermore, the current annual burden of HPVaCa and severe precancerous lesions was estimated. Incidence rate ratios and corresponding 95% confidence intervals for HPVaCa were calculated according to socioeconomic status. Results: The age-standardised incidence rate of HPV-associated cancers for the two sexes converged during the study period, and almost identical incidence rates were seen for women and men in the youngest birth cohorts. The current burden of HPV-associated lesions amounted to more than 5000 cases, the vast majority (85%) being severe precancerous lesions. The highest risk for HPV-associated cancers was associated with lower socioeconomic status. Conclusions: The burden of HPV-associated cancers among men will likely surpass that among women in the near future if the incidence trends continue. As many of these cancers and their precancerous lesions are associated with HPV type 16, a substantial proportion of cases are, in theory, preventable by the currently available vaccines.

Mapping HPV Vaccination and Cervical Cancer Screening Practice in the Pacific Region-Strengthening National and Regional Cervical Cancer Prevention

OBJECTIVE

To provide background information for strengthening cervical cancer prevention in the Pacific by mapping current human papillomavirus (HPV) vaccination and cervical cancer screening practices, as well as intent and barriers to the introduction and maintenance of national HPV vaccination programmes in the region.

MATERIALS AND METHODS

A cross-sectional questionnaire-based survey among ministry of health officials from 21 Pacific Island countries and territories (n=21).

RESULTS

Cervical cancer prevention was rated as highly important, but implementation of prevention programs were insufficient, with only two of 21 countries and territories having achieved coverage of cervical cancer screening above 40%. Ten of 21 countries and territories had included HPV vaccination in their immunization schedule, but only two countries reported coverage of HPV vaccination above 60% among the targeted population. Key barriers to the introduction and continuation of HPV vaccination were reported to be: (i) Lack of sustainable financing for HPV vaccine programs; (ii) Lack of visible government endorsement; (iii) Critical public perception of the value and safety of the HPV vaccine; and (iv) Lack of clear guidelines and policies for HPV vaccination.

CONCLUSION

Current practices to prevent cervical cancer in the Pacific Region do not match the high burden of disease from cervical cancer. A regional approach, including reducing vaccine prices by bulk purchase of vaccine, technical support for implementation of prevention programs, operational research and advocacy could strengthen political momentum for cervical cancer prevention and avoid risking the lives of many women in the Pacific.

Cancerous inhibitor of protein phosphatase 2A contributes to human papillomavirus oncoprotein E7-induced cell proliferation via E2F1

Cancerous inhibitor of protein phosphatase 2A (CIP2A) is a recently identified oncoprotein that is overexpressed in many human malignant tumors including cervical cancer. Human papillomavirus (HPV) oncoprotein E7 is the key transformation factor in cervical cancer. Our previous data showed a positive association of CIP2A and HPV-16E7 protein levels; however, how CIP2A is regulated by HPV-E7 and the roles of CIP2A in HPV-E7-mediated cell proliferation are unknown. In this study, we demonstrated that HPV-16E7 protein significantly upregulating CIP2A mRNA and protein expression depended on retinoblastoma protein pRb rather than p130. CIP2A siRNA knockdown in HPV-E7-expressing cells inhibited cell proliferation, DNA synthesis and G1/S cell cycle progression. CIP2A siRNA decreased the protein levels of cyclin-dependent kinase 1 (Cdk1), Cdk2 and their partner cyclin A2, with no change in levels of Cdk4, Cdk6 and their partner cyclin D1. The downregulation of Cdk1 and Cdk2 was independent of c-Myc; instead, E2F1 was the main target of CIP2A in this process, as overexpression of E2F1 rescued the inhibitory effects of CIP2A siRNA knockdown on cell proliferation and G1 arrest of HPV-E7-expressing cells. Our studies reveal a novel function of CIP2A in HPV-16E7-mediated cell proliferation.

Molecular concept in human oral cancer

The incidence of oral cancer remains high in both Asian and Western countries. Several risk factors associated with development of oral cancer are now well-known, including tobacco chewing, smoking, and alcohol consumption. Cancerous risk factors may cause many genetic events through chromosomal alteration or mutations in genetic material and lead to progression and development of oral cancer through histological progress, carcinogenesis. Oral squamous carcinogenesis is a multistep process in which multiple genetic events occur that alter the normal functions of proto-oncogenes/oncogenes and tumor suppressor genes. Furthermore, these gene alterations can deregulate the normal activity such as increase in the production of growth factors (transforming growth factor-α [TGF-α], TGF-β, platelet-derived growth factor, etc.) or numbers of cell surface receptors (epidermal growth factor receptor, G-protein-coupled receptor, etc.), enhanced intracellular messenger signaling and mutated production of transcription factors (ras gene family, c-myc gene) which results disturb to tightly regulated signaling pathways of normal cell. Several oncogenes and tumor suppressor genes have been implicated in oral cancer especially cyclin family, ras, PRAD-1, cyclin-dependent kinase inhibitors, p53 and RB1. Viral infections, particularly with oncogenic human papilloma virus subtype (16 and 18) and Epstein-Barr virus have tumorigenic effect on oral epithelia. Worldwide, this is an urgent need to initiate oral cancer research programs at molecular and genetic level which investigates the causes of genetic and molecular defect, responsible for malignancy. This approach may lead to development of target dependent tumor-specific drugs and appropriate gene therapy.

Genotypic distribution of human papillomavirus (HPV) and cervical cytology findings in 5906 Thai women undergoing cervical cancer screening programs

Background

Cervical cancer is the major cause of morbidity and mortality in Thai women. Nevertheless, the preventive strategy such as HPV vaccination program has not been implemented at the national level. This study explored the HPV prevalence and genotypic distribution in a large cohort of Thai women.

Methods

A hospital-based cervical cancer screening program at Chulabhorn Hospital, Bangkok and a population-based screening program at a rural Pathum Thani Province were conducted using liquid-based cytology and HPV genotyping.

Results

Of 5906 women aged 20–70 years, Pap smear was abnormal in 4.9% and the overall HPV prevalence was 15.1%, with 6.4% high-risk (HR), 3.5% probable high-risk (PR), and 8.4% low-risk (LR) HPV. The prevalence and genotypic distribution were not significantly different between the two cohorts. Among HR-HPV genotypes, HPV52 was the most frequent (1.6%), followed by HPV16 (1.4%), HPV51 (0.9%), HPV58 (0.8%), HPV18 (0.6%), and HPV39 (0.6%). Among LR-HPV genotypes, HPV72 and HPV62 were the most frequent while HPV6 and HPV11 were rare. HPV infection was found to be proportionately high in young women, aged 20–30 years (25%) and decreasing with age (11% in women aged >50). The more severe abnormal cytology results, the higher positivity of HR-HPV infection was observed.

Conclusions

In conclusion, HPV52, HPV16, and HPV51 were identified as the most common HR-HPV genotypes in Thai women. This study contributes genotypic evidence that should be essential for the development of appropriate HPV vaccination program as part of Thailand’s cervical cancer prevention strategies.

Human papillomavirus genotype distribution in cervical intraepithelial neoplasia grade 2/3 and invasive cervical cancer in Japanese women

OBJECTIVE

Human papillomavirus vaccines are being introduced worldwide and are expected to reduce the incidence of cervical cancer. Here we report a cross-sectional study using a validated human papillomavirus genotyping method to reveal the human papillomavirus prevalence and genotype distribution in Japanese women with cervical intraepithelial neoplasia Grade 2/3 and invasive cervical cancer.

METHODS

Cervical exfoliated cells were collected from 647 patients with abnormal cervical histology (cervical intraepithelial neoplasia Grade 2, n = 164; cervical intraepithelial neoplasia Grade 3, n = 334; and invasive cervical cancer, n = 149), and subjected to the PGMY-PCR-based genotyping assay. The association between human papillomavirus infection and lesion severity was calculated using a prevalence ratio.

RESULTS

Overall, the prevalence of human papillomavirus deoxyribonucleic acid was 96.3% in cervical intraepithelial neoplasia Grade 2, 98.8% in cervical intraepithelial neoplasia Grade 3 and 88.0% in invasive cervical cancer (97.8% in squamous cell carcinoma and 71.4% in adenocarcinoma). The three most prevalent types were as follows: human papillomavirus 16 (29.3%), human papillomavirus 52 (27.4%) and human papillomavirus 58 (22.0%) in cervical intraepithelial neoplasia Grade 2; human papillomavirus 16 (44.9%), human papillomavirus 52 (26.0%) and human papillomavirus 58 (17.4%) in cervical intraepithelial neoplasia Grade 3; and human papillomavirus 16 (47.7%), human papillomavirus 18 (23.5%) and human papillomavirus 52 (8.7%) in invasive cervical cancer. The prevalence ratio of human papillomavirus 16 was significantly higher in cervical intraepithelial neoplasia Grade 3 compared with cervical intraepithelial neoplasia Grade 2 (prevalence ratio, 1.62; 95% confidence interval, 1.26-2.13) and in squamous cell carcinoma compared with cervical intraepithelial neoplasia Grade 3 (prevalence ratio, 1.55; 95% confidence interval, 1.25-1.87). Multiple infections decreased from cervical intraepithelial neoplasia Grade 2/3 (38.4/29.6%) to invasive cervical cancer (14.1%), whereas co-infections with human papillomavirus 16/52/58 were found in cervical intraepithelial neoplasia Grade 2/3.

CONCLUSIONS

The results of this study provide pre-vaccination era baseline data on human papillomavirus type distribution in Japanese women and serve as a reliable basis for monitoring the future impact of human papillomavirus vaccination in Japan.

Correlates between risk perceptions of cervical cancer and screening practice

OBJECTIVES

To identify the correlates between risk perceptions and cervical cancer screening among urban Malaysian women.

METHOD

A cross-sectional household survey was conducted among 231 women in Petaling Jaya city in 2007. The association of risk perceptions of cervical cancer and screening practice was analyzed using Poisson regression.

RESULTS

56% of the respondents ever had a Pap smear test. Knowledge of signs and symptoms (aPR=1.11, 95% CI=1.03-1.19), age (aPR=1.02, 95% CI=1.01-1.03), number of pregnancies (aPR=1.06, 95% CI=1.01-1.11), marital status, education level and religion were found to be significant correlates of Pap smear screening. Respondents who were never married were less likely to have had a Pap smear. Those who had no education or primary education were less likely to have had a Pap smear compared to those with degree qualification. The prevalence of screening was significantly higher among Christians and others (aPR=1.35; 95% CI=1.01-1.81) and Buddhists (aPR=1.38; 95% CI=1.03-1.84), compared to Muslims.

CONCLUSION

Eliminating anecdotal beliefs as risks via targeted knowledge on established risk factors and culturally sensitive screening processes are strategic for increasing and sustaining uptake of Pap smear screening versus current opportunistic screening practices.

Potential impact of a nine-valent vaccine in human papillomavirus related cervical disease

Background

Information on human papillomavirus (HPV) type distribution is necessary to evaluate the potential impact of current and future HPV vaccines. We estimated the relative contribution (RC) to invasive cervical cancer (ICC) and precancerous cervical lesions of the nine HPV types (HPV 6/11/16/18/31/33/45/52/58) included in an HPV vaccine currently under development.

Methods

Estimations on ICC were based on an international study of 8,977 HPV positive cases and estimations on precancerous cervical lesions were extracted from a published meta-analysis including 115,789 HPV positive women. Globocan 2008 and 2010 World Population Prospects were used to estimate current and future projections of new ICC cases.

Results

RC of the 9 HPV types in ICC was 89.4%, with 18.5% of cases positive for HPV 31/33/45/52/58. Regional variations were observed. RCs varied by histology, ranging between 89.1% in squamous cell carcinomas (SCC) and 95.5% in adenocarcinomas (ADC). HPV 16/18/45 were detected in 94.2% of ADC. RC of the 9 types altogether decreased with age (trend test p < 0.0001), driven by the decrease in older ages of HPV 16/18/45. In contrast, the RC of HPV 31/33/52/58 increased with age. Due to population growth alone, projected estimates of ICC cases attributable to the 9 types are expected to rise from 493,770 new cases in 2012 to 560,887 new cases in 2025.

The RCs of individual high risk HPV types varied by cytological and histological grades of HPV-positive precancerous cervical lesions, and there was an under representation of HPV 18 and 45 compared to ICC.

Conclusions

The addition of HPV 31/33/45/52/58 to HPV types included in current vaccines could prevent almost 90% of ICC cases worldwide. If the nine-valent vaccine achieves the same degree of efficacy than previous vaccines, world incidence rates could be substantially reduced.

Recent progress in the application of nanotechnology for prevention and treatment of human papillomavirus infection

Human papillomavirus (HPV) causes benign and malignant infections of the anogenital tract. Cervical cancer, caused by high-risk HPV types 16, 18, 31, 33, 35, 45, 56 and 58, is the second most common cancer in women and the fifth most common cancer overall. Prevention and treatment of HPV infection may be revolutionized using nanotechnology tools such as vaccines based on virus-like particles and nanoscale drug-delivery systems. Advances in both virus-like particle design and noninvasive delivery of antiviral protein drugs, such as IFNalpha, may provide new opportunities to take on the challenge of global elimination of HPV infections. Biphasic vesicle cream formulation, representing a new class of dermal delivery system for protein drugs, is an alternative to injectable dosage form to deliver IFNalpha for the treatment of HPV infections, showing efficacy in low-grade squamous epithelical lesions of the cervix.

Prevalence and genotype distribution of cervical human papillomavirus infection among female sex workers in Asia: a systematic literature review and meta-analysis

Cervical human papillomavirus (HPV) infection is highly transmissible. Although there are many studies on HPV infection in general population of women globally, little attention has been paid to female sex workers (FSWs) in Asia. In this study, we used a meta-analytic approach to systematically analyse the literature to elucidate the prevalence and genotype distribution of cervical HPV infection among FSWs in Asia. Fourteen eligible studies were identified in five databases, and data including 4198 FSWs from nine Asian countries were aggregated. Crude estimates of cervical HPV prevalence among FSWs in this region ranged from 12.8% to 84.8%. FSWs had a nearly 10-fold risk of HPV infection than the general population of women. Stratified analysis showed that HPV prevalence was higher in East Asia than other subregions and in younger FSWs than older FSWs. HPV genotype distribution was statistically different between East Asia and South-east Asia. In East Asia, the most prevalent genotypes were HPV 16 (23.9%), 18 (11.0%), 58 (9.4%), 56 (6.3%) and 52 (5.3%), while they were HPV 52 (12.9%), 16 (8.5%), 58 (5.2%), 18 (5.0%) and 66 (4.9%) in South-east Asia. HPV 31, 33 and 35 were less frequently found in both subregions. HPV infection was substantial among FSWs in some Asian countries. More studies are necessary to illustrate the overall picture of HPV infection in this region.

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.

Impact of genital warts on health related quality of life in men and women in mainland China: a multicenter hospital-based cross-sectional study

Background

Information on the health-related quality of life (HRQoL) of patients with genital warts (GW) in populations in mainland China is still limited. The aim of the study was to use a generic instrument to measure the impact of genital warts on HRQoL in men and women in this setting.

Methods

A multi-centre hospital-based cross-sectional study across 18 centers in China was conducted to interview patients using the European quality of life-5 dimension (EQ-5D) instrument; respondents' demographic and clinical data were also collected.

Results

A total of 1,358 GW patients (612 men, 746 women) were included in the analysis, with a mean age of 32.0 ± 10.6 years. 56.4% of the patients reported some problems in the dimension of Anxiety/Depression (highest), followed by Pain/Discomfort (24.7%) and Mobility (3.5%). The overall visual analogue scale (VAS) score of the study population was found to be 65.2 ± 22.0, and the EQ-5D index score was found to be 0.843 ± 0.129 using Japanese preference weights (the Chinese preference was unavailable yet). Patients with lower VAS means and EQ-5D index scores were more often female, living in urban area, and suffering multiple GW (all p values < 0.05), but the values did not differ notably by age (p values > 0.05).

Conclusions

The HRQoL of patients with GW was substantially lower, compared to a national representative general population in China (VAS = ~80); the findings of different subgroups are informative for future GW prevention and control efforts.

Human papillomavirus in vaginal intraepithelial neoplasia

There are limited data on the prevalence and distribution of human papillomavirus (HPV) genotypes in vaginal intraepithelial neoplasia (VAIN). We sought to clarify this issue in a series of 450 VAIN cases with a confirmed diagnosis between 1990 and 2006. HPV genotyping was performed using paraffin-embedded specimens and polymerase chain reaction (PCR)-based methods. Multiple HPV types were validated by E6 type-specific PCR and direct sequencing. The HPV genotypes of the vaginal and cervical neoplasms were compared for those with incident VAIN and a history of previous/concomitant cervical neoplasms. Ki-67 was performed for supporting diagnosis of VAIN. Of these 450 VAIN cases (median age, 59 years; range, 19-93), two with missing paraffin blocks and 54 with poor DNA quality were excluded. HPV was detected in 273/394 (69.3%) VAIN, and multiple infections were found in 17.9% of HPV-positive samples. The leading types were HPV16 (35.5%), HPV58 (9.9%), HPV52 (9.9%), HPV39 (8.4%), HPV33 (7.3%) and HPV53 (7.0%). Among the 156 cases with a history of previous cervical neoplasia, 29.0% had concordant HPV genotypes, while synchronous VAIN samples (n = 49) were more likely to harbor concordant genotypes (58.7%) with the concomitant cervical neoplasm (p = 0.0003). Whether those HPV types in the incident VAIN lesions had existed in the vaginal epithelium at the time of the previous cervical neoplasia or a new acquisition needs to be clarified in prospective follow-up studies.

Expression of codon optimized major capsid protein (L1) of human papillomavirus type 16 and 18 in Pichia pastoris; purification and characterization of the virus-like particles

The major capsid protein (L1) of human papillomaviruses (HPV) expressed in heterologous systems assembles into virus-like particles (VLPs). We report cloning and expression of codon optimized HPV L1 genes of the two high-risk HPV types 16 and 18 in methylotropic yeast, Pichia pastoris. The VLPs produced in P. pastoris were subjected to three step purification method involving density gradient centrifugations and size exclusion chromatography. The enriched VLPs were characterized using conformation-specific monoclonal antibodies in ELISA and by transmission electron microscopy. Mice immunized with a bivalent HPV16 and HPV18 VLPs developed high serum antibody titers to both HPV types that persisted for 190 days post vaccination. Serum of mice immunized with the HPV-VLP preparations could neutralize homologous pseudoviruses in an in vitro assays. Our results demonstrate that the L1 proteins expressed in P. pastoris fold properly as evidenced by assembly into VLPs and induction of type-specific neutralizing antibody response in mice. This work constitutes a step towards developing an alternate production platform for generating an affordable HPV vaccine to meet the needs of developing countries.

Distribution patterns of infection with multiple types of human papillomaviruses and their association with risk factors

BACKGROUND

Infection with multiple types of human papillomavirus (HPV) is one of the main risk factors associated with the development of cervical lesions. In this study, cervical samples collected from 1,810 women with diverse sociocultural backgrounds, who attended to their cervical screening program in different geographical regions of Colombia, were examined for the presence of cervical lesions and HPV by Papanicolau testing and DNA PCR detection, respectively.

PRINCIPAL FINDINGS

The negative binomial distribution model used in this study showed differences between the observed and expected values within some risk factor categories analyzed. Particularly in the case of single infection and coinfection with more than 4 HPV types, observed frequencies were smaller than expected, while the number of women infected with 2 to 4 viral types were higher than expected. Data analysis according to a negative binomial regression showed an increase in the risk of acquiring more HPV types in women who were of indigenous ethnicity (+37.8%), while this risk decreased in women who had given birth more than 4 times (-31.1%), or were of mestizo (-24.6%) or black (-40.9%) ethnicity.

CONCLUSIONS

According to a theoretical probability distribution, the observed number of women having either a single infection or more than 4 viral types was smaller than expected, while for those infected with 2-4 HPV types it was larger than expected. Taking into account that this study showed a higher HPV coinfection rate in the indigenous ethnicity, the role of underlying factors should be assessed in detail in future studies.

Cancers attributable to human papillomavirus infection

Although the human papillomavirus (HPV) vaccine was introduced primarily as a cervical cancer prevention vaccine, HPV has a causal role in several types of cancer. This article reviews the epidemiological evidence for the role of HPV in human cancer, and describes Australian trends in these cancers. HPV is a necessary cause of cervical cancer. The currently vaccine-preventable subtypes of HPV 16 and 18 are responsible for ~70% of cervical cancer. The introduction of an organised Pap smear program in Australia led to a steep decline in incidence over the past decades. HPV can be detected in ~40% and 70% of vulval and vaginal cancers respectively. Rates of these cancers have been stable over the past 20 years. The prevalence of HPV in penile cancer is ~50% and incidence has not recently changed. For anal cancer, ~85% of cases are HPV positive, and incidence has increased significantly in both men and women over the past 20 years. In the oral cavity, ~35% of oropharyngeal cancers and ~25% of other oral cavity cancers are HPV positive. The incidence of HPV-related oral cavity and oropharyngeal cancers is increasing, whereas incidence at HPV-unrelated sites is decreasing. Overall, 1154 HPV-related cancer cases were potentially preventable by vaccination. If HPV-related cancers at non-cervical sites are prevented by vaccination, then a similar number of cancer cases will be prevented as in the cervix. However, almost one-quarter of the potentially preventable cancer cases are in men, who are not included in the current national immunisation program.

Distribution of human papillomavirus genotypes in sardinian patients with oral squamous cell carcinoma

Human papillomaviruses (HPVs) seem to play an important role in the pathogenesis of gynecological carcinomas and in head and neck carcinomas. The aim of this study was to detect and genotype HPVs in fresh oral squamous cell carcinoma (OSCC) from a Sardinian population, and to determine whether HPV presence was significantly associated with the development of OSCC.

The oral mucosa tissues were obtained from 120 samples (68 OSCC and 52 control samples) taken from a Sardinian population seen at the Dental Clinic of the Department of Surgery and Odontostomatological Sciences, University of Cagliari (Italy) and the “ Ospedale SS Trinità”, Cagliari (A.S.L. 8) between 2007 and 2008. PCR was used for the detection of HPV DNA and the genotype was determined by DNA sequencing. The frequency of HPV infection was evaluated in relation to age, sex, smoking and alcohol use. Statistical analysis was performed using the SPSS 11.5 software.

The results showed the presence of HPV-DNA in 60.3% of OSCC with HPV-16 (51.2%) being the most frequent genotype. In these Sardinian OSCC patients, HPV-DNA was detected more in males (65.8%) than in females (34.1%) while controls show a 0% of HPV presence. HPV positive was highly associated with OSCC among subjects with a history of heavy tobacco and alcohol use and among those with no such history.

A greater frequency of high risk HPV presence was observed in patients with OSCC compared to health control patients. In addition these results suggested that oral HPV presence could be associated in OSCC subjects. Our results need more analyses to detect the HPV-DNA integration into tumoral cells.

Perspectives for preventive and therapeutic HPV vaccines

Human Papillomavirus (HPV) has been associated with several human cancers, including cervical cancer, vulvar cancer, vaginal and anal cancer, and a subset of head and neck cancers. Thus effective vaccination against HPV provides an opportunity to reduce the morbidity and mortality associated with HPV. The Food and Drug Administration of the United States has approved two preventive vaccines to limit the spread of HPV. However, these are unlikely to impact upon HPV prevalence and cervical cancer rates for many years. Furthermore, preventive vaccines do not exert therapeutic effects on pre-existing HPV infections and HPV-associated lesions. In order to further impact upon the burden of HPV infections worldwide, therapeutic vaccines are being developed. These vaccines aim to generate a cell-mediated immune response to infected cells. This review discusses current preventive and therapeutic HPV vaccines and their future directions.

Fluorescence in situ hybridization markers for prediction of cervical lymph node metastases

The presence of lymph node metastases is associated with poor prognosis in early stage cervical cancer. As of yet, no molecular markers predicting lymph node metastases have been identified. We examined single genetic markers and a composite marker, comprised of three fluorescence in situ hybridization (FISH) probes targeting the genes LAMP3, PROX1, and PRKAA1, in pretreatment cervical biopsies from 16 lymph node positive cases and 15 lymph node negative controls from women with stage IB and IIA cervical cancer. In addition, we determined clonal patterns by including CCND1 to compare the clonal constitution of primary tumors and associated lymph node metastases. The composite FISH marker allowed for classification of patients into those with and without lymph node metastases with a sensitivity and specificity of 75% and 87%, respectively (P = 0.001). The positive predictive value and negative predictive value were 86% and 76%, respectively. Clonal patterns varied among the tumors. In many cases, changes between the primary tumor and lymph node metastases in the most common clones may indicate that certain clones have a growth advantage for establishing metastases in lymph nodes. We conclude that the composite FISH marker may be useful for determining risk for subsequent development of lymph node metastases in patients with cervical cancer.

The human papillomavirus type 58 E7 oncoprotein modulates cell cycle regulatory proteins and abrogates cell cycle checkpoints

HPV type 58 (HPV-58) is the third most common HPV type in cervical cancer from Eastern Asia, yet little is known about how it promotes carcinogenesis. In this study, we demonstrate that HPV-58 E7 significantly promoted the proliferation and extended the lifespan of primary human keratinocytes (PHKs). HPV-58 E7 abrogated the G1 and the postmitotic checkpoints, although less efficiently than HPV-16 E7. Consistent with these observations, HPV-58 E7 down-regulated the cellular tumor suppressor pRb to a lesser extent than HPV-16 E7. Similar to HPV-16 E7 expressing PHKs, Cdk2 remained active in HPV-58 E7 expressing PHKs despite the presence of elevated levels of p53 and p21. Interestingly, HPV-58 E7 down-regulated p130 more efficiently than HPV-16 E7. Our study demonstrates a correlation between the ability of down-regulating pRb/p130 and abrogating cell cycle checkpoints by HPV-58 E7, which also correlates with the biological risks of cervical cancer progression associated with HPV-58 infection.

Recommendations for cervical cancer prevention in Asia Pacific

Asia Oceania includes countries from both the Asia Pacific region and Australasia, which cover very diverse geographical areas and populations as well as bearing 52% of the cervical cancer burden in the world. Human papillomavirus (HPV) genotype distribution in women with normal cytology varies between countries in this region, as well as with the distribution typically observed in worldwide estimates or in Western countries. HPV-16 remains the predominant oncogenic type for high-grade cervical dysplasia and cervical cancer across the region, and HPV-18 is generally among the five most common types. HPV-58 is commonly found in cervical cancer as well as in women with normal cytology, and HPV-31, 33 and 35 are relatively less frequent in these regions compared to the West. While screening programmes have been proposed and implemented in several populations, successful programmes are rather limited and the majority of countries still have no or minimal screening services. Prophylactic HPV vaccination will only be feasible when it becomes affordable, thus the current priority and the short-term goal for cervical cancer control is to identify feasible and effective screening measures, and to find the most effective way to combine vaccination with sustainable screening programmes. This Regional Report has carefully described the disease burden of HPV and cervical cancer and the current situations in cervical cancer prevention for many countries in the Asia Oceania region. These data identify the many challenges and opportunities to be considered for policy decisions for cervical cancer control. Furthermore, this report presents the results of advanced decision analytic models calibrated to countries in the region that provide early insight into what strategies are most promising and those likely to be cost-effective and affordable. It thus provides a synthesis of the available evidence-based scientific information, in the context of a significant and systematic international review, that is likely to be useful to governments and public health providers.