Viral load in the natural history of human papillomavirus type 16 infection: a nested case-control study

Key aspects of papillomavirus infection influence the host cervicovaginal microbiome in a preclinical murine papillomavirus (MmuPV1) infection model

Human papillomaviruses (HPVs) are the most common sexually transmitted infection in the United States and are a major etiological agent of cancers in the anogenital tract and oral cavity. Growing evidence suggests changes in the host microbiome are associated with the natural history and ultimate outcome of HPV infection. We sought to define changes in the host cervicovaginal microbiome during papillomavirus infection, persistence, and pathogenesis using the murine papillomavirus (MmuPV1) cervicovaginal infection model. Cervicovaginal lavages were performed over a time course of MmuPV1 infection in immunocompetent female FVB/N mice and extracted DNA was analyzed by qPCR to track MmuPV1 viral copy number. 16S ribosomal RNA (rRNA) gene sequencing was used to determine the composition and diversity of microbial communities throughout this time course. We also sought to determine whether specific microbial communities exist across the spectrum of MmuPV1-induced neoplastic disease. We, therefore, performed laser-capture microdissection to isolate regions of disease representing all stages of neoplastic disease progression (normal, low- and high-grade dysplasia, and cancer) from female reproductive tract tissue sections from MmuPV1-infected mice and performed 16S rRNA sequencing. Consistent with other studies, we found that the natural murine cervicovaginal microbiome is highly variable across different experiments. Despite these differences in initial microbiome composition between experiments, we observed that MmuPV1 persistence, viral load, and severity of disease influenced the composition of the cervicovaginal microbiome. These studies demonstrate that papillomavirus infection can alter the cervicovaginal microbiome.IMPORTANCEHuman papillomaviruses (HPVs) are the most common sexually transmitted infection in the United States. A subset of HPVs that infect the anogenital tract (cervix, vagina, anus) and oral cavity cause at least 5% of cancers worldwide. Recent evidence indicates that the community of microbial organisms present in the human cervix and vagina, known as the cervicovaginal microbiome, plays a role in HPV-induced cervical cancer. However, the mechanisms underlying this interplay are not well-defined. In this study, we infected the female reproductive tract of mice with a murine papillomavirus (MmuPV1) and found that key aspects of papillomavirus infection and disease influence the host cervicovaginal microbiome. This is the first study to define changes in the host microbiome associated with MmuPV1 infection in a preclinical animal model of HPV-induced cervical cancer. These results pave the way for using MmuPV1 infection models to further investigate the interactions between papillomaviruses and the host microbiome.

Comparison of the ScreenFire and Xpert HPV assays for the detection of human papillomavirus and cervical precancer among women living with HIV in Malawi

BACKGROUND

The World Health Organization recommends human papillomavirus (HPV) testing for primary cervical cancer screening, including among women living with HIV (WLWH). Low-and-middle-income countries account for 85% of the cervical cancer burden globally, yet have limited access to HPV-based screening, largely due to cost. This study aims to compare the performance of a rapid, isothermal amplification HPV assay (ScreenFire) to that of the Xpert HPV assay for the detection of HPV and cervical precancer among WLWH in Malawi.

METHODS

We utilized stored self- and provider-collected specimens from a prospective cohort study of WLWH in Malawi from July 2020 to February 2022. Specimens were tested with both Xpert and ScreenFire HPV assays. The overall and within-channel non-hierarchical agreement between ScreenFire and Xpert was determined for both self- and provider-collected specimens. Hierarchical ScreenFire HPV positivity by channel was compared to Xpert for each histological diagnosis-cervical intraepithelial neoplasia grade 2 or worse (CIN2+) compared to

RESULTS

315 matched self- and provider-collected specimens had valid results from both Xpert and ScreenFire testing and were included in analyses, of which 279 and 36 were HPV positive and HPV negative, respectively, on Xpert self-collection. Of the 315, 245 (78%) had normal pathology, 21 CIN1 (7%), 14 CIN2 (4%), and 35 CIN3 (11%). Of the 245 with normal pathology, 213 (87%) and 188 (77%) were HPV-positive on Xpert and ScreenFire self-collected specimens, respectively. Among provider-collected specimens, the assays had 80% agreement on overall HPV positivity (unweighted kappa 0.59, 95% 0.50-0.69). ScreenFire was HPV-positive in 90% of self-collected specimens that were HPV-positive on Xpert. Channel agreement between the assays was high for both self- and provider-collected specimens, but slightly lower for HPV18/45. In hierarchical analysis, ScreenFire demonstrated high concordance with Xpert testing for detecting CIN2+ cases in all channels, missing no HPV 16 or HPV 18/45 positive CIN2+ case that was positive on Xpert, in both self- and provider-collected specimens.

CONCLUSION

In this study of stored specimens, the ScreenFire HPV assay performed well in the detection of HPV and CIN2+ among WLWH compared to the Xpert HPV assay. If supported by larger validation studies, ScreenFire could be an affordable alternative point-of-care HPV assay for use in LMICs.

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Grants

• K12 HD103085 NICHD NIH HHS
• U54 CA254564 NCI NIH HHS
• K12HD103085 Eunice Kennedy Shriver National Institute of Child Health & Human Development of the National Institutes of Health
• Eunice Kennedy Shriver National Institute of Child Health & Human Development of the National Institutes of Health

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Affiliation(s)

Chemtai Mungo Department of Obstetrics and Gynecology, University of North Carolina-Chapel Hill, Chapel Hill, NC, USA.
Anagha Guliam Barnard College of Columbia University, New York City, NY, USA
Lameck Chinula Department of Obstetrics and Gynecology, University of North Carolina-Chapel Hill, Chapel Hill, NC, USA University of North Carolina Project-Malawi, Lilongwe, Malawi
Federica Inturrisi Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, MD, USA
Lizzie Msowoya University of North Carolina Project-Malawi, Lilongwe, Malawi
Tawonga Mkochi University of North Carolina Project-Malawi, Lilongwe, Malawi
Siniya Jawadu University of North Carolina Project-Malawi, Lilongwe, Malawi
Silvia de Sanjosé Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, MD, USA ISGlobal, Barcelona, Spain
Mark Schiffman Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, MD, USA
Jennifer H Tang Department of Obstetrics and Gynecology, University of North Carolina-Chapel Hill, Chapel Hill, NC, USA University of North Carolina Project-Malawi, Lilongwe, Malawi
Jennifer S Smith Gillings School of Global Public Health, University of North Carolina-Chapel Hill, Chapel Hill, NC, USA

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Comparison of the ScreenFire and Xpert HPV assays for the detection of human papillomavirus and cervical precancer among women living with HIV in Malawi

Background

The World Health Organization (WHO) recommends human papillomavirus (HPV) testing for primary cervical cancer screening, including among women living with HIV (WLWH). Low-and-middle-income countries (LMICs) account for 85% of the cervical cancer burden globally, yet have limited access to HPV-based screening, largely due to cost. This study aims to compare the performance of a rapid, isothermal amplification HPV assay (ScreenFire) to that of the Xpert HPV assay for the detection of HPV and cervical precancer among WLWH in Malawi.

Methods

We utilized stored self- and provider-collected specimens from a prospective cohort study of WLWH in Malawi from July 2020 to February 2022. Specimens were tested with both Xpert and ScreenFire HPV assays. The overall and within-channel non-hierarchical agreement between ScreenFire and Xpert was determined for both self- and provider-collected specimens. Hierarchical ScreenFire HPV positivity by channel was compared to Xpert for each histological diagnosis - cervical intraepithelial neoplasia grade 2 or worse (CIN2+) compared to

Results

315 matched self- and provider-collected specimens had valid results from both Xpert and ScreenFire testing and were included in analyses. Of these, 245 (78%) had normal pathology, 21 CIN1 (7%), 14 CIN2 (4%), and 35 CIN3 (11%). Among provider-collected specimens, the assays had 80% agreement on overall HPV positivity (unweighted kappa 0.59, 95% 0.50-0.69). ScreenFire was HPV-positive in 90% of self-collected specimens that were HPV-positive on Xpert. Channel agreement between the assays was high for both self- and provider-collected specimens, but slightly lower for HPV18/45. In hierarchical analysis, ScreenFire demonstrated high concordance with Xpert testing for detecting CIN2+ cases in all channels, missing no HPV 16 or HPV 18/45 positive CIN2+ case that was positive on Xpert, in both self- and provider-collected specimens.

Conclusion

In this study of stored specimens, the ScreenFire HPV assay performed well in the detection of HPV and CIN2+ among WLWH compared to the Xpert HPV assay. If supported by larger validation studies, ScreenFire could be an affordable alternative point-of-care HPV assay for use in LMICs.

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Key Words Collapse

MESH Headings Collapse

Grants

• K12 HD103085 NICHD NIH HHS

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Affiliation(s)

Chemtai Mungo Department of Obstetrics and Gynecology, University of North Carolina-Chapel Hill
Anagha Guliam Barnard College of Columbia University
Lameck Chinula Department of Obstetrics and Gynecology, University of North Carolina-Chapel Hill University of North Carolina Project-Malawi, Lilongwe, Malawi
Federica Inturrisi Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, MD, USA
Lizzie Msowoya University of North Carolina Project-Malawi, Lilongwe, Malawi
Tawonga Mkochi University of North Carolina Project-Malawi, Lilongwe, Malawi
Siniya Jawadu University of North Carolina Project-Malawi, Lilongwe, Malawi
Silvia de Sanjosé Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, MD, USA Gillings School of Global Public Health, University of North Carolina-Chapel Hill
Mark Schiffman Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, MD, USA
Jennifer H. Tang Department of Obstetrics and Gynecology, University of North Carolina-Chapel Hill University of North Carolina Project-Malawi, Lilongwe, Malawi
Jennifer S. Smith Gillings School of Global Public Health, University of North Carolina-Chapel Hill

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A rapid HPV typing assay to support global cervical cancer screening and risk-based management: A cross-sectional study

The World Health Organization recommends human papillomavirus (HPV) testing for cervical screening. Extended genotyping can identify the highest-risk HPV-positive women. An inexpensive, rapid, mobile isothermal amplification assay (ScreenFire HPV RS test) was recently redesigned to yield four channels ordered by cancer risk (ie, hierarchical approach): HPV16, HPV18/45, HPV31/33/35/52/58 and HPV39/51/56/59/68. Stored specimens from 2076 women (mean age 30.9) enrolled in a colposcopy clinic, with high HPV prevalence, were tested with ScreenFire. We calculated hierarchical channel positivity and non-hierarchical channel and type positivity, according to histologic diagnosis (256 cancer, 350 cervical intraepithelial neoplasia [CIN]3, 409 CIN2, 1020 < CIN2) and known virologic reference results (Linear Array and TypeSeq). Additionally, we analyzed ScreenFire time-to-positive up to 60 min by channel and histology. Overall clinical sensitivity for CIN3+ was 94.7% (95% confidence interval 92.6-96.4), similar to Linear Array (92.3, 89.7-94.3) and TypeSeq (96.0, 93.9-97.6). Sensitivity was high for all types and channels. The hierarchical approach was well in line with HPV typing and histologic diagnosis, prioritizing higher risk women having HPV16 and precancer. For HPV16, time-to-positive was shorter in women with precancer. ScreenFire showed excellent agreement with research reference typing tests and detection of CIN2+. Risk-based type results could help guide clinical management of HPV-positive women. Time-to-positive combined with genotyping might be useful. ScreenFire is rapid, mobile, relatively inexpensive and designed for implementation of HPV-based screening and management, including in lower-resource settings. Further validation in screening by self-sampling and practical effectiveness merit evaluation.

The clinical effectiveness of one-dose vaccination with an HPV vaccine: A meta-analysis of 902,368 vaccinated women

BACKGROUND

The comprehensive effectiveness of the HPV vaccine has been widely acknowledged. However, challenges such as dosing adherence and limited budgets have led to delays in HPV vaccination implementation in many countries. A potential solution to these issues could lie in a one-dose vaccination with an HPV vaccine, as indicated by promising outcomes in multiple studies.

METHODS

In this systematic review and meta-analysis, we examine the comparative effectiveness of the one-dose vaccination with an HPV vaccine against two- and three-dose regimens. Our investigation focuses on clinical efficacy, encompassing the prevention of HPV16, HPV18, and hrHPV infections, HSIL or ASC-H incidence, and CIN2/3 incidence.

RESULTS

Our analysis suggests that a single-dose HPV vaccine may offer effectiveness on par with two- or three-dose schedules. This conclusion is drawn from its capacity to confer immunogenic protection for at least 8 years of follow-up, coupled with its ability to mitigate infections and pre-cancerous occurrences.

CONCLUSION

While our findings underscore the potential of the one-dose vaccination with an HPV vaccine, further research and prolonged study durations are necessary to establish robust evidence supporting this recommendation. As such, continued investigation will be critical for informing vaccination strategies.

Characterization of HPV subtypes in invasive cervical cancer in Botswana patients using a pan-pathogen microarray technology

Human papillomavirus (HPV) plays a significant role in the development of cervical cancers in the setting of co-infection with HIV. Botswana has a high prevalence of HIV and cervical cancer. In this study, we investigated the distribution of HPV subtypes in cervical cancer biopsy samples from patients in Botswana using a highly sensitive pan-pathogen microarray technology, PathoChip, to detect both high- (HR-HPV) and low-risk HPV (LR-HPV) subtypes in women living with HIV (WLWH) and women living without HIV. We analyzed samples from 168 patients, of which 73% (n = 123) were WLWH with a median CD4 count of 479.5 cells/μL. Five HR-HPV subtypes were detected in the cohort: HPV 16, 18, 26, 34, and 53. The most prevalent subtypes were HPV 26 (96%) and HPV 34 (92%); 86% of WLWH (n = 106) had co-infection with four or more HR-HPV subtypes compared to 67% (n = 30) of women without HIV (p < 0.01). We detected 66 LR-HPV subtypes among all cervical cancer patients, with HPV 6b and 48 being most prevalent. Notably, signatures for LR-HPV subtypes 10, 41, 90, and 129 were only detected in WLWH. Signal intensity for HPV 18 was significantly weaker in WLWH with CD4 levels ≤200 cells/μL as compared to patients with >200 cells/μL and HIV-negative patients. Although the majority of cervical cancer specimens in this cohort were determined to have multiple HPV infections, the most prevalent HR-HPV subtypes (HPV 26 and HPV34) found in these cervical cancer samples are not covered in the current HPV vaccines. Though no conclusions can be made on the direct carcinogenicity of these subtypes the results do underlie the need for continued screening for prevention of cervical cancer.

Stress keratin 17 and estrogen support viral persistence and modulate the immune environment during cervicovaginal murine papillomavirus infection

A murine papillomavirus, MmuPV1, infects both cutaneous and mucosal epithelia of laboratory mice and can be used to model high-risk human papillomavirus (HPV) infection and HPV-associated disease. We have shown that estrogen exacerbates papillomavirus-induced cervical disease in HPV-transgenic mice. We have also previously identified stress keratin 17 (K17) as a host factor that supports MmuPV1-induced cutaneous disease. Here, we sought to test the role of estrogen and K17 in MmuPV1 infection and associated disease in the female reproductive tract. We experimentally infected wild-type and K17 knockout (K17KO) mice with MmuPV1 in the female reproductive tract in the presence or absence of exogenous estrogen for 6 mon. We observed that a significantly higher percentage of K17KO mice cleared the virus as opposed to wild-type mice. In estrogen-treated wild-type mice, the MmuPV1 viral copy number was significantly higher compared to untreated mice by as early as 2 wk postinfection, suggesting that estrogen may help facilitate MmuPV1 infection and/or establishment. Consistent with this, viral clearance was not observed in either wild-type or K17KO mice when treated with estrogen. Furthermore, neoplastic disease progression and cervical carcinogenesis were supported by the presence of K17 and exacerbated by estrogen treatment. Subsequent analyses indicated that estrogen treatment induces a systemic immunosuppressive state in MmuPV1-infected animals and that both estrogen and K17 modulate the local intratumoral immune microenvironment within MmuPV1-induced neoplastic lesions. Collectively, these findings suggest that estrogen and K17 act at multiple stages of papillomavirus-induced disease at least in part via immunomodulatory mechanisms.

A comprehensive HPV-STI NGS assay for detection of 29 HPV types and 14 non-HPV sexually transmitted infections

BACKGROUND

Sexually transmitted infections (STIs) are prevalent throughout the world and impose a significant burden on individual health and public health systems. Missed diagnosis and late treatment of STIs can lead to serious complications such as infertility and cervical cancer. Although sexually transmitted co-infections are common, most commercial assays target one or a few STIs. The HPV-STI ChapterDx Next Generation Sequencing (NGS) assay detects and quantifies 29 HPVs and 14 other STIs in a single-tube and single-step PCR reaction and can be applied to tens to thousands of samples in a single sequencing run.

METHODS

A cohort of 274 samples, previously analyzed by conventional cytology/histology and Roche cobas HPV Test, were analyzed by ChapterDx HPV-STI NGS assay for detection of 43 HPV and STI. A set of 43 synthetic control DNA fragments for 43 HPV and STI were developed to evaluate the limit of detection, specificity, and sensitivity of ChapterDx HPV-STI NGS assay.

RESULTS

The assay was evaluated in this study, and the limit of detection was 100% at 50 copies for all targets, and 100%, 96%, 88% at 20 copies for 34, 8, and 1 target, respectively. The performance of this assay has been compared to Roche cobas HPV test, showing an overall agreement of 97.5% for hr-HPV, and 98.5% for both, HPV16 and HPV18. The assay also detected all HPV-infected CIN2/3 with 100% agreement with Roche cobas HPV results. Moreover, several co-infections with non-HPV STIs, such as C. trachomatis, T. vaginalis, M. genitalium, and HSV2 were identified.

CONCLUSIONS

The ChapterDx HPV-STI NGS assay is a user-friendly, easy to automate and cost-efficient assay, which provides accurate and comprehensive results for a wide spectrum of HPVs and STIs.

Prognostic impact of human papillomavirus infection on cervical dysplasia, cancer, and patient survival in Saudi Arabia: A 10-year retrospective analysis

BACKGROUND

Data on human papillomavirus (HPV) prevalence and survival rates among HPV-infected women are scarce in Saudi Arabia.

OBJECTIVE

Assess the prevalence of HPV genotypes in cervical biopsy specimens and its effect on survival over a 10-year timeframe.

DESIGN

Retrospective, cross-sectional.

SETTINGS

Saudi referral hospital.

PATIENTS AND METHODS

Cervical biopsy specimens were collected from women aged 23-95 years old who underwent HPV detection, HPV genotyping, p16^INK4a expression measurement using immunohistochemistry. Kaplan-Meier plots were constructed to analyze overall survival rates.

MAIN OUTCOME MEASURES

Survival rate of HPV-positive cervical cancer patients.

SAMPLE SIZE

315 cervical biopsy specimens.

RESULTS

HPV was detected in 96 patients (30.4%): 37.3% had cervical cancer; 14.2% cervical intraepithelial neoplasia (CIN) III, 4.1% CIN II, and 17.0% CIN I. A significant association was found between HPV presence and cervical cancer (χ²=56.78; P<.001). The expression of p16^INK4a was a significant predictor of survival: women who had p16^INK4a overexpression had poorer survival rates (multivariate Cox regression, hazard ratio, 3.2; 95% CI, 1.1-8.8). In addition, multivariate models with HPV status and cervical cancer diagnosis showed that HPV status was a significant predictor of survival: HPV-positive women had better survival rates than HPV-negative women.

CONCLUSION

These findings suggest that implementing cervical and HPV screening programs may decrease cervical cancer rates and improve survival rates of women in Saudi Arabia.

LIMITATION

Single center and small sample size.

CONFLICT OF INTEREST

None.

Significance of the viral load of high-risk HPV in the diagnosis and prediction of cervical lesions: a retrospective study

BACKGROUND

The significance of HPV viral load in the detection of cervical lesions is still controversial. This study analyzed the correlation between the high-risk HPV viral load and different cervical lesion degrees.

METHODS

This retrospective study included women positive for high-risk HPV DNA and screened for cervical lesions between 01/2015 and 06/2018. The high-risk HPV DNA load was measured by the second-generation Hybrid Capture technology and classified as low, moderate, and high. Colposcopy and biopsy were performed in all patients. The patients were grouped as normal, cervical intraepithelial neoplasia (CIN) grade 1, CIN grade 2, CIN grade 3, and cervical cancer. Multivariable logistic regression was performed to explore the association between high-risk HPV DNA load and cervical lesions. The odds ratios (ORs) represent the odds for increasing from low to high viral load.

RESULTS

Finally, 265 patients were grouped as normal (n = 125), CIN 1 (n = 51), CIN 2 (n = 23), CIN 3 (n = 46), and cervical cancer (n = 20). Among them, 139 (52.5%) had a low viral load, 90 (34.0) had a moderate viral load, and 36 (13.4%) had a high viral load. Taking the normal control group as a reference, a high viral load was an independent factor for CIN 1 (OR = 3.568, 95% CI: 1.164-10.941, P = 0.026), CIN 2 (OR = 6.939, 95% CI: 1.793-26.852, P = 0.005), CIN 3 (OR = 7.052, 95% CI: 2.304-21.586, P = 0.001), and cervical cancer (OR = 8.266, 95% CI: 2.120-32.233, P = 0.002).

CONCLUSIONS

Among women who underwent cervical biopsy, higher high-risk HPV viral load in cervical lesions was associated with a higher risk of high-grade cervical lesions.

DETERMINING PROBABILITY OF CANCER CELL TRANSFOMATION AT HUMAN PAPILLOMAVIRUS INFECTION

Aim. The purpose of the work was to assess the probability of cancerous transformation of cells for viruses of high and low oncogenic risk. Aim. The purpose of the work was to assess the probability of cancerous transformation of cells for viruses of high and low oncogenic risk. Results. Using normalized squared error (NSE) for viruses of high (20 strains) and low (153 strains) oncogenic risk, rank statistic of 2-exponential type was build. For productive papillomavirus infection, NSE function was determined as the growing accurate 2-exponent of a cell layer basal to the epithelial surface. Logarithm of NSE numerical values is proportional to the cell entropy that is connected with the availability of virus DNA. To calculate entropy, generalized Hartley formula was used with the informational cell of dimension d: H = NdLOG(NSE), where N is the generalized cell coordinate. Conclusions. Using a statistical ensemble of E6 proteins separately for viruses of high and low oncogenic risk made it possible to assess the probability of cancerous transformation of cells, which was proportional to the ratio of the area of entropy of cancer transformation to the area of the productive entropy region papillomavirus infection.

HPV16 Load Is a Potential Biomarker to Predict Risk of High-Grade Cervical Lesions in High-Risk HPV-Infected Women: A Large Longitudinal French Hospital-Based Cohort Study

Simple Summary

This study aimed at assessing HPV16 and HPV18 viral loads to predict the development of cervical high-grade lesion. Among 885 women positive for hrHPV and presenting no or mild cytological abnormalities, HPV16 and HPV18 prevalence was 25.9% and 8.4%, respectively. Of those women, 135 developed a high-grade lesion during the follow-up. Considering an HPV16 viral load cut-off set at 3.2 log₁₀ GE/10³ cells a subgroup of women at high risk of developing high-grade cervical lesion (HR = 2.67; 95% CI 1.80–3.97 p ≤ 0.0001) has been identified. Moreover, a composite score based on HPV16 load, cytology and hrHPV detection allowed for CIN2+ risk stratification. To conclude, HPV16 load is a relevant biomarker to identify women at high risk for developing precancerous lesions of the cervix.

Abstract

High-risk HPV (hrHPV) testing has been implemented as a primary screening tool for cervical cancer in numerous countries. However, there is still a need for relevant triage strategies to manage hrHPV positive women to avoid excessive referral to colposcopy. The objective of this study was to assess, in women infected by hrHPV and presenting no or mild cytological abnormalities, HPV16 and HPV18 viral loads to predict the development of cervical high-grade lesion. Among 2102 women positive for hrHPV, 885 had no lesion or mild cytological abnormalities at baseline and had at least one follow-up (FU) visit. HPV16 and HPV18 prevalence was 25.9% and 8.4%, respectively. Of those women, 15% developed a high-grade lesion during the FU. An HPV16 viral load cut-off set at 3.2 log₁₀GE/10³ cells permitted to identify a subgroup of women at high risk of developing high-grade cervical lesion (HR = 2.67; 95% CI 1.80–3.97; p ≤ 0.0001). No specific HPV18 viral load threshold could have been defined in regard to the present study. In multivariate analysis, HPV16 load (absence/log₁₀GE/10³ cells < 3.2 vs. ≥3.2), RLU/PC 239 (1–100 pg/mL vs. >100 pg/mL) and cytology (normal vs abnormal) were independently associated with a significant increased risk of high-grade lesion development and were used to construct the prognostic score. In conclusion, HPV16 load is a relevant biomarker to identify women at high risk for developing cervical precancerous lesions.

Viral load and high prevalence of HR-HPV52 and 58 types in black women from rural communities

Background

The high-risk human papillomavirus (HR-HPV) infection is the main cause of cervical cancer development, and the most common types were included in the last approved nonavalent vaccine (9vHPV). Geographical, socioeconomic and ethnic barriers in developing countries challenge primary and secondary prevention measures of cervical cancer. We aimed to determine the prevalence of HPV infection and the viral load of HR-HPV 9vHPV-related types black women resident in rural semi-isolated communities.

Methods

A descriptive study was conducted with 273 cervical samples of women from rural communities of Southeastern Brazil. Viral DNA was amplified by PCR, the genotype was identified by Reverse Line Blot (RLB) and Restriction Fragment Length Polymorphism (RFLP), and real-time PCR was applied to determine the viral load.

Results

HPV frequency was 11.4% (31/273), associated with the presence of cytological abnormalities (32.3%; p < 0.001). Thirty-one distinct genotypes were detected; HR-HPV occurred in 64.5% (20/31) of the samples and the most prevalent type were HPV52 > 58, 59. Multiple infections occurred with up to nine different genotypes. The viral load of HR-HPV 9vHPV-related types was higher in lesions than in normal cytology cases (p = 0.04); “high” and “very high” viral load occurred in HSIL and LSIL, respectively (p = 0.04).

Conclusions

We highlight that despite the low HPV frequency in the black rural women population, the frequency of HR-HPV was high, particularly by the HR-HPV52 and 58 types. Moreover, the HR-HPV viral load increased according to the progression from normal to lesion, being a potential biomarker to identify those women at higher risk of developing cervical lesions in this population.

Development and validation of a multiplex qPCR assay for detection and relative quantification of HPV16 and HPV18 E6 and E7 oncogenes

Human papillomaviruses (HPV) play a key role in promoting human anogenital cancers. Current high-risk HPV screening or diagnosis tests involve cytological or molecular techniques mostly based on qualitative HPV DNA detection. Here, we describe the development of a rapid quantitative polymerase chain reaction (qPCR) detection test of HPV16 and HPV18 oncogenes (E6 and E7) normalized on human gene encoding GAPDH. Optimized qPCR parameters were defined, and analytical specificities were validated. The limit of detection was 10¹ for all genes tested. Assay performances were evaluated on clinical samples (n = 96). Concordance between the Xpert HPV assay and the triplex assay developed here was 93.44% for HPV16 and 73.58% for HPV18. HPV co-infections were detected in 15 samples. The systems developed in the present study can be used in complement to traditional HPV tests for specifically validating the presence of HPV16 and/or HPV18. It can also be used for the follow-up of patients with confirmed infection and at risk of developing lesions, through the quantification of E6 and E7 oncogene expression (mRNA) normalized on the GAPDH expression levels.

Real-time loop-mediated isothermal amplification assay for rapid detection of human papillomavirus 16 in oral squamous cell carcinoma

OBJECTIVE

The present study established a real-time loop-mediated isothermal amplification (qLAMP) for rapid detection of human papillomavirus subtype 16 (HPV-16) in oral squamous cell carcinoma (OSCC).

METHODS

The qLAMP assay was optimized targeting the HPV-16 E7 gene. The analytical sensitivity and specificity of the assay were determined using HPV-18 (ATCC® 45152D™), HPV-35 (ATCC® 40330™), HPV-43 (ATCC® 40338™) and HPV-56 (ATCC® 40549™) viral strains and oral bacteria. HPV-16 standard curve was constructed for determination of HPV-16 viral load. The diagnostic performance of the assay was evaluated from 63 OSCC patients comprising 63 tissue, 13 saliva and 49 blood samples, in comparison with p16 immunohistochemistry (IHC), in-house PCR and nested PCR assays.

RESULTS

The detection limit of developed LAMP and PCR assays was 4.68 × 10¹ and 4.68 × 10³ copies/μl, respectively. qLAMP assay enabled detection of positive results as early as 23 min at 67 °C. This assay can detect HPV-16 positivity in 23 % (3/13) saliva and 4.8 % (3/63) tissue samples with the viral load ranging from 4.68 × 10¹ to 4.68 × 10⁴ copies/μl. HPV-16 positivity was not detected in all the blood samples. The sensitivity and specificity of qLAMP were 100 % in comparison with that of p16 IHC and nested PCR.

CONCLUSION

This study reports for the first time on the use of qLAMP assay for detection of HPV-16 in OSCC in both tissue and saliva as the sample matrix which holds promise in improving the diagnostic application owing to its rapidity, simplicity, high sensitivity and specificity.

Chapter XX Antiviral Treatment and Cancer Control

Hepatitis B virus (HBV), hepatitis C virus (HCV), human papilloma virus (HPV), Epstein-Barr virus (EBV), human T-cell lymphotropic virus type 1 (HTLV-1), Kaposi's sarcoma-associated herpesvirus (KSHV), and Merkel cell polyomavirus (MCV) contribute to about 10-15% global burden of human cancers. Conventional chemotherapy or molecular target therapies have been used to treat virus-associated cancers. However, a more proactive approach would be the use of antiviral treatment to suppress or eliminate viral infections to prevent the occurrence of cancer in the first place. Antiviral treatments against chronic HBV and HCV infection have achieved this goal, with significant reduction in the incidence of hepatocellular carcinoma in treated patients. Antiviral treatments for EBV, KSHV, and HTLV-1 had limited success in treating refractory EBV-associated lymphoma and post-transplant lymphoproliferative disorder, KSHV-associated Kaposi's sarcoma in AIDS patients, and HTLV-1-associated acute, chronic, and smoldering subtypes of adult T-cell lymphoma, respectively. Therapeutic HPV vaccine and RNA interference-based therapies for treating HPV-associated infection or cervical cancers also showed some encouraging results. Taken together, antiviral therapies have yielded promising results in cancer prevention and treatment. More large-scale studies in a real-world setting are necessary to confirm the efficacy of antiviral therapy. Further investigation for more effective and convenient antiviral regimens warrants more attention.

Viral load and interaction of HPV oncoprotein E6 and E7 with host cellular markers in the progression of cervical cancer

<abstract> <p>Cervical cancer is the sequel of a multi-factorial, long-term unresolved disease that includes genetic, epigenetic, and viral components responsible for its development and progression. It is the second most common cancer of females in India. Human papillomavirus (HPV) is considered the primary causative agent of pre-neoplastic and cancerous lesions and 90% of all cervical carcinomas are linked to high-risk HPV type 16 and type 18. Although most HR-HPV infections are asymptomatic, transient, and self-limiting, the persistent infection with a high risk (HR-HPV) may cause precancerous lesions that can progress to cervical cancer. HPV type 16 is the most common HPV in India associated with more than 75% of cervical cancer, followed by HPV type 18 and other high-risk types. Infection with HPV alone is not sufficient for the development of cervical cancer but there is the involvement of some host genetic factors also that are responsible for the development and progression of cervical cancer. This article briefly reviews molecular pathogenesis, viral load, and the interaction of HPV oncoprotein E6 and E7 with host cellular markers in the progression of cervical cancer.</p> </abstract>

Cervical cancer risk profiling: molecular biomarkers predicting the outcome of hrHPV infection

INTRODUCTION

Cervical cancer affects half a million women worldwide annually. Given the association between high-risk human papillomavirus (hrHPV) infection and carcinogenesis, hrHPV DNA testing became an essential diagnostic tool. However, hrHPV alone does not cause the disease, and, most importantly, many cervical lesions regress to normal in a year because of the host immune system. Hence, the low specificity of hrHPV DNA tests and their inability to predict the outcome of infections have triggered a further search for biomarkers.

AREAS COVERED

We evaluated the latest viral and cellular biomarkers validated for clinical use as primary screening or triage for cervical cancer and assessed their promise for prevention as well as potential use in the future. The literature search focused on effective biomarkers for different stages of the disease, aiming to determine their significance in predicting the outcome of hrHPV infections.

EXPERT OPINION

Biomarkers such as p16/Ki-67, hrHPV genotyping, hrHPV transcriptional status, and methylation patterns have demonstrated promising results. Their eventual implementation in the screening programs may support the prompt diagnosis of hrHPV infection and its progression to cancer. These biomarkers will help in making clinical management decisions on time, thus, saving the lives of hrHPV-infected women, particularly in developing countries.

Cervical screening: ESGO-EFC position paper of the European Society of Gynaecologic Oncology (ESGO) and the European Federation of Colposcopy (EFC)

This paper summarises the position of ESGO and EFC on cervical screening based on existing guidelines and opinions of a team of lead experts. HPV test is replacing cytology as this offers greater protection against cervical cancer and allows longer screening intervals. Only a dozen of HPV tests are considered as clinically validated for screening. The lower specificity of HPV test dictates the use of triage tests that can select women for colposcopy. Reflex cytology is currently the only well validated triage test; HPV genotyping and p16 immunostaining may be used in the future, although methylation assays and viral load also look promising. A summary of quality assurance benchmarks is provided, and the importance to audit the screening histories of women who developed cancer is noted as a key objective. HPV-based screening is more cost-effective than cytology or cotesting. HPV-based screening should continue in the post-vaccination era. Only a fraction of the female population is vaccinated, and this varies across countries. A major challenge will be to personalise screening frequency according to vaccination status. Still the most important factor for successful prevention by screening is high population coverage and organised screening. Screening with self-sampling to reach under-screened women is promising.

Human papillomavirus prevalence and risk factors among HIV-negative and HIV-positive women residing in rural Eastern Cape, South Africa

OBJECTIVES

To investigate the prevalence of high-risk (HR) human papillomavirus (HPV) and factors associated with HR-HPV infection among women from rural Eastern Cape, South Africa.

METHODS

HPV prevalence was determined by Hybrid Capture 2 assay in cervical specimens from 417 women aged ≥30 years (median 46 years) recruited from the community health clinic in the Eastern Cape.

RESULTS

HR-HPV prevalence was 28.5% (119/417), and HIV-positive women had significantly higher HR-HPV prevalence than HIV-negative women (40.6%, 63/155 vs 21.4%, 56/262, respectively; p = 0.001). HIV-positive status (odds ratio (OR) 2.52, 95% confidence interval (CI) 1.63-3.90), having ≥3 lifetime sexual partners (OR 2.12, 95% CI 1.16-3.89), having ≥1 sexual partner in the last month (OR 1.89, 95% CI 1.21-2.92), ≥4 times frequency of vaginal sex in the past 1 month (OR 2.40, 95% CI 1.32-4.35), and having a vaginal discharge currently/in the previous week (OR 2.13, 95% CI 1.18-3.85) increased the risk of HR-HPV infection. In the multivariate analysis, HIV positivity remained strongly associated with HR-HPV infection (OR 1.94, 95% CI 1.17-3.22).

CONCLUSIONS

Risk factors related to sexual behaviors play a significant role in HR-HPV infection in this population. This report will inform health policymakers on HPV prevalence and contribute to discussions on the use of HPV testing as the primary cervical cancer screening test in South Africa.

HPV viral load in self-collected vaginal fluid samples as predictor for presence of cervical intraepithelial neoplasia

OBJECTIVE

This study was performed to evaluate the use of high-risk HPV (hrHPV) viral load in screening tests for cervical cancer to predict persistent infection and presence of cervical intraepithelial neoplasia grade 2 or worse (CIN2+).

METHODS

We followed women between 30 and 60 years of age who performed self-sampling of vaginal fluid and subsequently a hrHPV test. Women who were hrHPV positive in their screening test repeated the hrHPV test 3-6 months later and were included in the present study.

RESULTS

Our results show that women with a persistent HPV16 infection had higher HPV viral load in their primary screening test than women with transient infections (p = 5.33e-03). This was also true for sum of viral load for all hrHPV types in the primary screening test (p = 3.88e-07). 48% of women with persistent HPV16 infection and CIN2+ had an increase in HPV16 titer in the follow-up test, as compared to only 20% of women with persistent infection but without CIN2+ lesions. For the sum of all hrHPV types, 41% of women with persistent infection and CIN2+ had an increase in titer as compared to 26% of women without CIN2 + .

CONCLUSIONS

The results show that hrHPV viral load in the primary screening HPV test is associated with the presence of CIN2+ and could be used in triaging hrHPV positive women for different follow-up strategies or recall times. Serial testing of hrHPV viral load has the potential to distinguish women with CIN2+ lesions from women with persistent infection but without CIN2+ lesions.

Viral load of human papillomavirus types 16/18/31/33/45 as a predictor of cervical intraepithelial neoplasia and cancer by age

OBJECTIVE

We assessed whether human papillomavirus (HPV) viral load is an independent predictor of underlying cervical disease and its diagnostic accuracy by age.

METHODS

The Biomarkers of Cervical Cancer Risk study was a case-control study from 2001 to 2010 in Montréal, Canada. Cases were histologically-confirmed cervical intraepithelial neoplasia (CIN), adenocarcinoma in situ (AIS), or cervical cancer cases. Controls were women presenting for routine screening with normal cytology results. We quantified HPV16/18/31/33/45 viral load from exfoliated cervical cells using a real-time PCR assay. Diagnostic accuracy of viral load was assessed using the area under the receiver operating characteristic curve (AUC). We restricted the analysis to the 632 cases and controls who were HPV16/18/31/33/45 positive.

RESULTS

Geometric mean HPV16/18/31/33/45 viral load increased with severity of lesion grade, ranging from 0.7, 3.1, 4.8, 7.2, and 12.4 copies/cell in normal, CIN1, CIN2, CIN3&AIS, and cervical cancer respectively. The adjusted odds ratio of CIN1+ and CIN2+ increased respectively by 1.3 (95%CI 1.1-1.4) and 1.2 (95%CI 1.1-1.3) per log-transformed viral copy/cell increase of HPV16/18/31/33/45. This association was mainly driven by HPV16, 18, and 31 viral loads. The AUC of HPV16/18/31/33/45 viral load for discriminating between normal and CIN1+ women was 0.70 (95%CI 0.64-0.76) in HPV-positive women, and was 0.76 (95%CI 0.66-0.86) for women ≥30 years and 0.66 (95%CI 0.58-0.74) for women under 30 years.

CONCLUSIONS

HPV viral load has lower diagnostic accuracy than has been reported for other HPV screening triage tests. However, it may be useful for triaging HPV tests in settings without cytology results such as HPV self-sampling.

Role of HPV Genotype, Multiple Infections, and Viral Load on the Risk of High-Grade Cervical Neoplasia

BACKGROUND

Human papillomavirus (HPV) testing provides a much more sensitive method of detection for high-grade lesions than cytology, but specificity is low. Here, we explore the extent to which full HPV genotyping, viral load, and multiplicity of types can be used to improve specificity.

METHODS

A population-based sample of 47,120 women undergoing cervical screening was tested for 13 high-risk HPV genotypes. Positive predictive values (PPV) for cervical intraepithelial neoplasia (CIN) grade 2 or worse (CIN2+; N = 3,449) and CIN3 or worse (CIN3+; N = 1,475) over 3 years of follow-up were estimated for HPV genotype and viral load. Weighted multivariate logistic regression models were used to estimate the odds of CIN2+ or CIN3+ according to genotype, multiplicity of types, and viral load.

RESULTS

High-risk HPV was detected in 15.4% of women. A hierarchy of HPV genotypes based on sequentially maximizing PPVs for CIN3+ found HPV16>33>31 to be the most predictive, followed sequentially by HPV18>35>58>45>52>59>51>39>56>68. After adjusting for higher ranked genotypes, the inclusion of multiple HPV infections added little to risk prediction. High viral loads for HPV18, 35, 52, and 58 carried more risk than low viral loads for HPV16, 31, and 33. High viral load for HPV16 was significantly more associated with CIN3+ than low viral load.

CONCLUSIONS

HPV genotype and viral load, but not multiplicity of HPV infections, are important predictors of CIN2+ and CIN3+.

IMPACT

The ability to identify women at higher risk of CIN2+ and CIN3+ based on both HPV genotype and viral load could be important for individualizing triage plans, particularly as HPV becomes the primary screening test.

Level of phospho-STAT3 (Tyr705) correlates with copy number and physical state of human papillomavirus 16 genome in cervical precancer and cancer lesions

Our earlier studies indicated an important role of inducible transcription factor STAT3 in the establishment of persistent infection of human papillomavirus (HPV) type 16 and promotion of cervical carcinogenesis. Since HPV load and its physical state are two potential determinants of this virally-induced carcinogensis, though with some exceptions, we extended our study to examine the role of active STAT3 level in cervical precancer and cancer lesions and it’s association with HPV viral load and physical state. An elevated level of active STAT3 was measured by assessing phospho-STAT3-Y705 (pSTAT3), in tumor tissues harboring higher viral load irrespective of the disease grade. Physical state analysis of HPV16 by assessing the degree of amplification of full length E2 and comparing it with E6 (E2:E6 ratio), which predominantly represent episomal form of HPV16, revealed low or undetectable pSTAT3. A strong pSTAT3 immunoreactivity was found in tissues those harbored either mixed or predominantly integrated form of viral genome. Cumulative analysis of pSTAT3 expression, viral load and physical state demonstrated a direct correlation between pSTAT3 expression, viral load and physical state of HPV. The study suggests that there exists a strong clinical correlation between level of active STAT3 expression and HPV genome copy number, and integrated state of the virus that may play a pivotal role in promotion/maintanence of tumorigenic phenotype.

Association of Human Papillomavirus Genotype 16 Viral Variant and Viral Load with Cervical High-grade Intraepithelial Lesions

Human papillomavirus genotype 16 (HPV16) is by far the genotype most strongly associated with cervical cancer; viral variant and/or viral load of HPV16 could modulate this association. The objective was to determine the association between the viral variant and viral load of HPV16 and the presence of cervical high-grade lesions. This cross-sectional study included all women in whom HPV infection was found by cervical smear during routine gynecologic health checks. Women with single or multiple HPV16 infections (n = 176) were selected for viral variant and viral load analysis. Smear results were classified using the Bethesda system. HPV types were classified according to the International Agency for Research on Cancer. Odds ratios (OR) with their 95% confidence intervals (CI) were estimated by logistic regression, adjusted for age, immigrant status, and coinfection with other high-risk genotypes. No statistically significant associations were found regarding the detected viral variants. A viral load above the median (>1,367.79 copies/cell) was associated with a significant risk of high-grade epithelial lesion or carcinoma, after adjusting for age, immigrant status, coinfections, and viral variant: (adjusted OR 7.89; 95% CI: 2.75-22.68). This relationship showed a statistically significant dose-response pattern after categorizing by viral load tertiles: adjusted OR for a viral load greater than the third tertile was 17.23 (95% CI: 4.20-70.65), with adjusted linear P _trend = 0.001. In patients infected with HPV16, viral load is associated with high-grade intraepithelial lesions or cervical carcinoma. This could be useful as prognostic biomarker of neoplastic progression and as screening for cervical cancer.

Development and interlaboratory agreement of real-time PCR for HPV16 quantification in liquid-based cervical samples

High risk HPV infection is the necessary cause for the development of precancerous and cancerous lesions of the cervix. Among HPV, HPV16 represents the most carcinogenic type. Since the determination of HPV16 DNA load could be clinically useful, we assessed quantitative real-time PCR targeting E6HPV16 and albumin genes on two different platforms. Series of SiHa cells diluted in PreservCyt were used to assess repeatability and reproducibility of two in-house real-time PCR techniques run in two different laboratories to determine HPV16 load. Furthermore, 97 HPV16 positive cervical samples were evaluated to estimate inter-center variability using Bland-Alman plots. As a whole, both techniques presented coefficients of variation for HPV16 load measurement similar to those established for other virus quantification with commercial kits. Moreover, the two real-time PCR techniques showed a very good agreement for HPV16 load calculation. Finally, we emphasize that robust HPV16 DNA quantification requires normalization of viral load by the cell number.

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HPV16 viral load could be a useful biomarker for the management of HPV positive women.

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Coefficient of variation for HPV16 viral load ranged from 7% to 62%.

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HPV16 viral load quantification requires normalization by the cell number.

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HPV16 viral load precision increases with the use of an internal calibrator.

Validation of a Human Papillomavirus (HPV) DNA Cervical Screening Test That Provides Expanded HPV Typing

As cervical cancer screening shifts from cytology to human papillomavirus (HPV) testing, a major question is the clinical value of identifying individual HPV types. We aimed to validate Onclarity (Becton Dickinson Diagnostics, Sparks, MD), a nine-channel HPV test recently approved by the FDA, by assessing (i) the association of Onclarity types/channels with precancer/cancer; (ii) HPV type/channel agreement between the results of Onclarity and cobas (Roche Molecular Systems, Pleasanton, CA), another FDA-approved test; and (iii) Onclarity typing for all types/channels compared to typing results from a research assay (linear array [LA]; Roche). We compared Onclarity to histopathology, cobas, and LA. We tested a stratified random sample (n = 9,701) of discarded routine clinical specimens that had tested positive by Hybrid Capture 2 (HC2; Qiagen, Germantown, MD). A subset had already been tested by cobas and LA (n = 1,965). Cervical histopathology was ascertained from electronic health records. Hierarchical Onclarity channels showed a significant linear association with histological severity. Onclarity and cobas had excellent agreement on partial typing of HPV16, HPV18, and the other 12 types as a pool (sample-weighted kappa value of 0.83); cobas was slightly more sensitive for HPV18 and slightly less sensitive for the pooled high-risk types. Typing by Onclarity showed excellent agreement with types and groups of types identified by LA (kappa values from 0.80 for HPV39/68/35 to 0.97 for HPV16). Onclarity typing results corresponded well to histopathology and to an already validated HPV DNA test and could provide additional clinical typing if such discrimination is determined to be clinically desirable.

Prospective comparison of hybrid capture 2 and SPF₁₀-LiPA for carcinogenic human papillomavirus detection and risk prediction of cervical cancer: a population-based cohort study in China

Objective

To investigate the extent of the cross-reactivity of hybrid capture 2 (HC2) assay and evaluate the potential effect of cross-reactivity on the long-term risk for cervical cancer and precancers.

Methods

Based on the Shanxi Province Cervical Cancer Screening Study-I (SPOCCS-I) cohort from 2005 to 2014 in Shanxi, China, SPF₁₀-line probe assay (LiPA) was performed in all 598 HC2 positive and 300 random-selected HC2 negative cervical specimens. Ten-year cumulative incidence rate (CIR) of cervical intraepithelial neoplasia grade 2 or worse (CIN2+) of these two tests was evaluated using Kaplan-Meier methods. Possible human papillomavirus (HPV) types to be cross-reacted by HC2 were also analyzed.

Results

The overall agreement between HC2 and SPF₁₀-LiPA for detecting carcinogenic HPV was 73.27%. The highest 10-year cumulative risk of CIN2+ was observed in both HC2 positive and LiPA-carcinogenic HPV positive women (25.70%; 95% confidence interval [CI]=23.55%–27.91%), followed by HC2 positive but LiPA-non-carcinogenic HPV positive women (9.97%; 95% CI=8.57%–11.50%), HC2 negative but LiPA-carcinogenic HPV positive (2.56%; 95% CI=2.44%–2.70%) and HC2 positive but LiPA-HPV negative (1.85%; 95% CI=1.78%–1.92%) women. The proportion of cross-reactivity of HC2 with untargeted carcinogenic types was 8.9%, most of which were attributable to HPV26, 73, 82, 69, 71, 53, 11, 43, and 54.

Conclusion

The noticeable high risk of CIN2+ in women infected with cross-reacted non-carcinogenic HPV and low risk in those with miss-to-detective carcinogenic HPV supported an overall good clinical performance of HC2 for a general cervical cancer screening.

Physical state and copy numbers of HPV16 in oral asymptomatic infections that persisted or cleared during the 6-year follow-up

Persistent human papillomavirus (HPV) infection is a key event in HPV-induced carcinogenesis. As part of the prospective Finnish Family HPV Study, we analysed the physical state and viral copy numbers of HPV16 in asymptomatic oral infections that either persisted or cleared during the 6-year follow-up. The persister group comprised 14 women and 7 men with 51 and 21 HPV16-positive brush samples. The clearance group included 41 women and 13 men, with 64 and 24 samples, respectively. Physical state and viral DNA load were assessed by using quantitative PCR for HPV16 E2 and E6 genes. E2/E6 ratio was calculated and HPV16 was classified as episomal, mixed or integrated with values of 0.93-1.08, <0.93 and 0, respectively. In both genders, the physical state of HPV16 was significantly different between the cases and controls (P<0.001). HPV16 was episomal in all men and 66 % (27/41) of women who cleared their infection. HPV16 was mixed and/or integrated in71 % and 57 %of the women and men persisters, respectively. The mean HPV16 copy number per 50 ng genomic DNA was nearly 5.5-fold higher in the women than in the men clearance group (P=0.011). Only in men, HPV16 copy numbers were higher in persisters than in the clearance group (P=0.039). To conclude, in both genders, persistent oral HPV16 infections were associated with the mixed or integrated form of HPV16, while in the clearance groups, episomal HPV16 predominated. This indicates that HPV16 integration is a common event even in asymptomatic oral infections, which might predispose the infected subjects to progressive disease.

Viral load and integration status of HPV58 associated with cervical lesion severity in women of Northeast China

Objective

We aimed to evaluate the viral load and integration status of human papillomavirus 58 in women with different grades of cervical lesions to determine whether viral load and integration status are related to malignant transformation in HPV58-infected women.

Methods

A total of 212 cervical specimens were collected from women in Northeast China who had undergone human papillomavirus genotyping and were HPV58-positive. The HPV58 viral load was determined using real-time polymerase chain reaction, and the integration status was discriminated using the ratio of HPV58 E2 gene copy number to E6 gene copy number.

Results

The median HPV58 viral load in women with normal cervix or cervicitis, low-grade squamous cell intraepithelial lesion, high-grade squamous cell intraepithelial lesion and cervical cancer was 352.12, 864.21, 1199.75 and 693.04 copies/genome, respectively. High significance was obtained when comparing the viral load of infected women presenting normal/cervicitis with that of the women either with precancerous cervical lesions or cervical cancer (P < 0.05). The HPV58 genome was in the episomal form in 35 samples (16.5%), mixed episomal and integrated forms in 165 (77.8%) samples, and completely integrated into the host genome in 12 (5.7%) samples. The HPV58 E2/E6 copy number ratio in the cervical cancer group was significantly lower than that in the other groups (P < 0.01).

Conclusions

The HPV58 viral load in patients with precancerous cervical lesions or cervical cancer increases significantly with disease progression. The HPV58 E2/E6 copy number ratio in patients with cervical cancer is lower than that for less severe cervical lesions, suggesting a high degree of viral integration may be a considerable risk factor for cervical cancer.

Type-dependent association between risk of cervical intraepithelial neoplasia and viral load of oncogenic human papillomavirus types other than types 16 and 18

Studies of the clinical relevance of human papillomavirus (HPV) DNA load have focused mainly on HPV16 and HPV18. Data on other oncogenic types are rare. Study subjects were women enrolled in the atypical squamous cells of undetermined significance (ASC-US) and low-grade squamous intraepithelial lesion (LSIL) triage study who had ≥1 of 11 non-HPV16/18 oncogenic types detected during a 2-year follow-up at 6-month intervals. Viral load measurements were performed on the first type-specific HPV-positive specimens. The association of cervical intraepithelial neoplasia grades 2-3 (CIN2/3) with type-specific HPV DNA load was assessed with discrete-time Cox regression. Overall, the increase in the cumulative risk of CIN2/3 per 1 unit increase in log₁₀ -transformed viral load was statistically significant for four types within species 9 including HPV31 (adjusted hazard ratio [HR _adjusted ] = 1.32: 95% confidence interval [CI], 1.14-1.52), HPV35 (HR _adjusted  = 1.47; 95% CI, 1.23-1.76), HPV52 (HR _adjusted  = 1.14; 95% CI, 1.01-1.30) and HPV58 (HR _adjusted  = 1.49; 95% CI, 1.23-1.82). The association was marginally significant for HPV33 (species 9) and HPV45 (species 7) and was not appreciable for other types. The per 1 log₁₀ -unit increase in viral load of a group of species 9 non-HPV16 oncogenic types was statistically significantly associated with risk of CIN2/3 for women with a cytologic diagnosis of within normal limits, ASC-US, or LSIL at the first HPV-positive visit but not for those with high-grade SIL. Findings suggest that the viral load-associated risk of CIN2/3 is type-dependent, and mainly restricted to the species of HPV types related to HPV16, which shares this association.

Linear viral load increase of a single HPV-type in women with multiple HPV infections predicts progression to cervical cancer

Persistent high-risk human papillomavirus (HPV) infection is strongly associated with development of high-grade cervical intraepithelial neoplasia or cancer (CIN3+). In single type infections, serial type-specific viral-load measurements predict the natural history of the infection. In infections with multiple HPV-types, the individual type-specific viral-load profile could distinguish progressing HPV-infections from regressing infections. A case-cohort natural history study was established using samples from untreated women with multiple HPV-infections who developed CIN3+ (n = 57) or cleared infections (n = 88). Enriched cell pellet from liquid based cytology samples were subjected to a clinically validated real-time qPCR-assay (18 HPV-types). Using serial type-specific viral-load measurements (≥3) we calculated HPV-specific slopes and coefficient of determination (R(2) ) by linear regression. For each woman slopes and R(2) were used to calculate which HPV-induced processes were ongoing (progression, regression, serial transient, transient). In transient infections with multiple HPV-types, each single HPV-type generated similar increasing (0.27copies/cell/day) and decreasing (-0.27copies/cell/day) viral-load slopes. In CIN3+, at least one of the HPV-types had a clonal progressive course (R(2)  ≥ 0.85; 0.0025copies/cell/day). In selected CIN3+ cases (n = 6), immunostaining detecting type-specific HPV 16, 31, 33, 58 and 67 RNA showed an even staining in clonal populations (CIN3+), whereas in transient virion-producing infections the RNA-staining was less in the basal layer compared to the upper layer where cells were ready to desquamate and release newly-formed virions. RNA-hybridization patterns matched the calculated ongoing processes measured by R(2) and slope in serial type-specific viral-load measurements preceding the biopsy. In women with multiple HPV-types, serial type-specific viral-load measurements predict the natural history of the different HPV-types and elucidates HPV-genotype attribution.

Detection of Human Papillomavirus Infections at the Single-Cell Level

OBJECTIVE

To explore the possibility of single-cell analysis of human papillomavirus (HPV) infection.

METHODS

Two hundred and twenty cells were isolated by laser capture microdissection from formalin-fixed and paraffin-embedded cervical tissue blocks from 8 women who had HPV DNA detected in their cervical swab samples. The number of type-specific HPV copies in individual cells was measured by quantitative polymerase chain reaction with and without a prior reverse transcription. The cells were assayed and counted for more than once if the corresponding swab sample was positive for ≥2 HPV types.

RESULTS

Infection with HPV16, HPV39, HPV51, HPV52, HPV58, HPV59 and HPV73 was detected in 12 (5.5%) of 220, 3 (9.4%) of 32, 3 (5.8%) of 52, 11 (22.9%) of 48, 9 (18.8%) of 48, 3 (9.4%) of 32 and none of 20 cells, respectively. The numbers of HPV genome copies varied widely from cell to cell. The coexistence of multiple HPV types was detected in 6 (31.6%) of 19 positive cells from 1 of the 6 women who had 2 or 3 HPV types detected in their swab samples.

CONCLUSION

Given the heterogeneity of HPV status in individual cells, further clarification of HPV infection at the single-cell level may refine our understanding of HPV-related carcinogenesis.

Detection of high-risk human papillomavirus using menstrual blood in women with high-grade squamous intraepithelial lesions or high-risk human papillomavirus infections: A pilot study

AIM

Few studies have reported that human papillomavirus (HPV) tests using menstrual blood (MB) may be a convenient and effective screening modality for cervical cancer. Therefore, we aimed to investigate the efficacy of detecting high-risk (HR)-HPV from MB in women with high-grade squamous intraepithelial lesions or HR-HPV infections dependent on menstrual days.

MATERIALS AND METHODS

In this prospective exploratory pilot study, a clinical trial was conducted in 19 women. On enrollment into the study, gynecologists collected cervical cells. On the first and second day of menstruation, MB was self-collected by patients using a sanitary pad with a filter. The distribution of HPVs from MB and the accuracy of menstrual HR-HPV tests were evaluated using HPV genotyping. The agreement rate of detecting HR-HPVs using cervical and MB samples was also investigated.

RESULTS

The sensitivity, specificity, positive and negative predictive values of the MB HR-HPV test for detecting cervical intraepithelial neoplasia (CIN) 3 or worse were 87.5%, 45.5%, 53.8%, and 83.3%, respectively, during both menstrual cycle day (MCD) 1 and 2 and MCD 1 only; and 62.5%, 27.3%, 38.5%, and 50.0%, respectively, during MCD 2 only. For CIN 3 or worse, the agreement rate between positive cervical and MB HR-HPV test results was 87.5% during MCD 1 and 62.5% during MCD 2.

CONCLUSIONS

We demonstrated the possibility of using the MB HPV test as a screening modality for cervical cancer.

Partner Human Papillomavirus Viral Load and Incident Human Papillomavirus Detection in Heterosexual Couples

BACKGROUND

The association between partner human papillomavirus (HPV) viral load and incident HPV detection in heterosexual couples is unknown.

METHODS

HPV genotypes were detected in 632 human immunodeficiency virus (HIV)-negative couples followed for 2 years in a male circumcision trial in Rakai, Uganda, using the Roche HPV Linear Array. This assay detects 37 genotypes and provides a semiquantitative measure of viral load based on the intensity (graded 1-4) of the genotype-specific band; a band intensity of 1 indicates a low genotype-specific HPV load, whereas an intensity of 4 indicates a high load. Using Poisson regression with generalized estimating equations, we measured the association between partner's genotype-specific viral load and detection of that genotype in the HPV-discordant partner 1 year later.

RESULTS

Incident detection of HPV genotypes was 10.6% among men (54 of 508 genotype-specific visit intervals) and 9.0% among women (55 of 611 genotype-specific visit intervals). Use of male partners with a baseline genotype-specific band intensity of 1 as a reference yielded adjusted relative risks (aRRs) of 1.14 (95% confidence interval [CI], .58-2.27]) for incident detection of that genotype among women whose male partner had a baseline band intensity of 2, 1.75 (95% CI, .97-3.17) among those whose partner had an intensity of 3, and 2.52 (95% CI, 1.40-4.54) among those whose partner had an intensity of 4. Use of female partners with a baseline genotype-specific band intensity of 1 as a reference yielded an aRR of 2.83 (95% CI, 1.50-5.33) for incident detection of that genotype among men whose female partner had a baseline band intensity of 4. These associations were similar for high-risk and low-risk genotypes. Male circumcision also was associated with significant reductions in incident HPV detection in men (aRR, 0.53 [95% CI, .30-.95]) and women (aRR, 0.42 [95% CI, .23-.76]).

CONCLUSIONS

In heterosexual couples, the genotype-specific HPV load in one partner is associated with the risk of new detection of that genotype in the other partner. Interventions that reduce the HPV load may reduce the incidence of HPV transmission.

Association of Human Papillomavirus 31 DNA Load with Risk of Cervical Intraepithelial Neoplasia Grades 2 and 3

The association between human papillomavirus 31 (HPV31) DNA loads and the risk of cervical intraepithelial neoplasia grades 2 and 3 (CIN2-3) was evaluated among women enrolled in the atypical squamous cells of undetermined significance (ASCUS) and low-grade squamous intraepithelial lesion (LSIL) triage study (ALTS), who were monitored semiannually over 2 years and who had HPV31 infections detected at ≥1 visit. HPV31 DNA loads in the first HPV31-positive samples and in a random set of the last positive samples from women with ≥2 HPV31-positive visits were measured by a real-time PCR assay. CIN2-3 was histologically confirmed at the same time as the first detection of HPV31 for 88 (16.6%) of 530 women. After adjustment for HPV31 lineages, coinfection with other oncogenic types, and the timing of the first positive detection, the odds ratio (OR) per 1-log-unit increase in viral loads for the risk of a concurrent diagnosis of CIN2-3 was 1.5 (95% confidence interval [CI], 1.2 to 1.9). Of 373 women without CIN2-3 at the first positive visit who had ≥1 later visit, 44 had subsequent diagnoses of CIN2-3. The initial viral loads were associated with CIN2-3 diagnosed within 6 months after the first positive visit (adjusted OR, 1.5 [95% CI, 1.0 to 2.4]) but were unrelated to CIN2-3 diagnosed later. For a random set of 49 women who were tested for viral loads at the first and last positive visits, changes in viral loads were upward and downward among women with and without follow-up CIN2-3 diagnoses, respectively, although the difference was not statistically significant. Results suggest that HPV31 DNA load levels at the first positive visit signal a short-term but not long-term risk of CIN2-3.

Analysis of longitudinal multivariate outcome data from couples cohort studies: application to HPV transmission dynamics

We consider a specific situation of correlated data where multiple outcomes are repeatedly measured on each member of a couple. Such multivariate longitudinal data from couples may exhibit multi-faceted correlations which can be further complicated if there are polygamous partnerships. An example is data from cohort studies on human papillomavirus (HPV) transmission dynamics in heterosexual couples. HPV is a common sexually transmitted disease with 14 known oncogenic types causing anogenital cancers. The binary outcomes on the multiple types measured in couples over time may introduce inter-type, intra-couple, and temporal correlations. Simple analysis using generalized estimating equations or random effects models lacks interpretability and cannot fully utilize the available information. We developed a hybrid modeling strategy using Markov transition models together with pairwise composite likelihood for analyzing such data. The method can be used to identify risk factors associated with HPV transmission and persistence, estimate difference in risks between male-to-female and female-to-male HPV transmission, compare type-specific transmission risks within couples, and characterize the inter-type and intra-couple associations. Applying the method to HPV couple data collected in a Ugandan male circumcision (MC) trial, we assessed the effect of MC and the role of gender on risks of HPV transmission and persistence.

Short-term natural history of high-risk human papillomavirus infection in mid-adult women sampled monthly

Characterizing short-term HPV detection patterns and viral load may inform HPV natural history in mid-adult women. From 2011-2012, we recruited women aged 30-50 years. Women submitted monthly self-collected vaginal samples for high-risk HPV DNA testing for 6 months. Positive samples were tested for type-specific HPV DNA load by real-time PCR. HPV type-adjusted linear and Poisson regression assessed factors associated with (i) viral load at initial HPV detection and (ii) repeat type-specific HPV detection. One-hundred thirty-nine women (36% of 387 women with ≥4 samples) contributed 243 type-specific HR HPV infections during the study; 54% of infections were prevalent and 46% were incident. Incident (vs. prevalent) detection and past pregnancy were associated with lower viral load, whereas current smoking was associated with higher viral load. In multivariate analysis, current smoking was associated with a 40% (95% CI: 5-87%) increase in the proportion of samples that were repeatedly positive for the same HPV type, whereas incident (vs. prevalent) detection status and past pregnancy were each associated with a reduction in the proportion of samples repeatedly positive (55%, 95% CI: 38-67% and 26%, 95% CI: 10-39%, respectively). In a separate multivariate model, each log10 increase in viral load was associated with a 10% (95% CI: 4-16%) increase in the proportion of samples repeatedly positive. Factors associated with repeat HPV detection were similar to those observed in longer-term studies, suggesting that short-term repeat detection may relate to long-term persistence. The negative associations between incident HPV detection and both viral load and repeat detection suggest that reactivation or intermittent persistence was more common than new acquisition.

High Oral Human Papillomavirus Type 16 Load Predicts Long-term Persistence in Individuals With or at Risk for HIV Infection

The association between oral human papillomavirus 16 (HPV16) DNA load and infection clearance was evaluated among 88 individuals with oral HPV16 infection who were identified within a prospective cohort of 1470 HIV-infected and uninfected individuals. Oral rinse specimens were collected semiannually for up to 5 years. The oral HPV16 load at the time of the first positive test result was significantly associated with the time to clearance of infection (continuous P trends <.01). Notably, clearance rates by 24 months were 41% and 94% in the highest and lowest HPV16 load tertiles (P = .03), respectively. High oral HPV16 load warrants consideration as a biomarker for infection persistence, the presumed precursor of HPV16-associated oropharyngeal cancer.

Reliability of the Xpert HPV assay to detect high-risk human papillomavirus DNA in a colposcopy referral population

OBJECTIVES

The Xpert HPV Assay (Xpert; Cepheid, Sunnyvale, CA) was developed for the multianalytic GeneXpert platform.

METHODS

In a colposcopy referral population of 708 women living in the United States, two cervical specimens, A and B, were collected, and both were tested by the Xpert assay for high-risk human papillomavirus (hrHPV) DNA, permitting an evaluation of its test reliability. Specimen B was also tested by Hybrid Capture 2 (hc2; Qiagen, Germantown, MD) and the cobas HPV Test (cobas; Roche Molecular Systems, Pleasanton, CA).

RESULTS

The κ and percent agreement for any hrHPV for the two Xpert results were 0.88 and 94.5%, respectively. There was no statistical difference in testing positive on both specimens by Xpert (P = .62). The sensitivity for detection of cervical intraepithelial neoplasia grade 2 or more severe (CIN2+) was 89.0% using specimen A and 90.4% using specimen B for Xpert, 90.4% for cobas, and 81.6% for hc2.

CONCLUSIONS

The Xpert assay was sensitive and reliable for the detection of hrHPV and the identification of women with CIN2+.

Long-term risk of cervical intraepithelial neoplasia grade 3 or worse according to high-risk human papillomavirus genotype and semi-quantitative viral load among 33,288 women with normal cervical cytology

In this prospective cohort study, we estimated the long-term risk of cervical intraepithelial neoplasia grade 3 or cancer (CIN3+) by high-risk human papillomavirus (hrHPV) genotype and semi-quantitative viral load at baseline among 33,288 women aged 14-90 years with normal baseline cytology. During 2002-2005, residual liquid-based cervical cytology samples were collected from women screened for cervical cancer in Copenhagen, Denmark. Samples were HPV-tested with Hybrid Capture 2 (HC2) and genotyped with INNO-LiPA. Semi-quantitative viral load was measured by HC2 relative light units in women with single hrHPV infections. The cohort was followed in a nationwide pathology register for up to 11.5 years. In women aged ≥30 years at baseline, the 8-year absolute risk for CIN3+ following baseline detection of HPV16 was 21.8% (95% confidence interval [CI]: 18.0-25.6%). The corresponding risks for HPV18, HPV31, HPV33, and other hrHPV types, respectively, were 12.8% (95% CI: 7.6-18.0%), 11.3% (95% CI: 7.7-14.9%), 12.9% (95% CI: 7.0-18.8%) and 3.9% (95% CI: 2.7-5.2%). Similar absolute risk estimates were observed in women aged <30 years. Higher HPV16-viral load was associated with increased risk of CIN3+ (hazard ratio = 1.34, 95% CI: 1.10-1.64, per 10-fold increase in viral load). A similar trend, although statistically nonsignificant, was found for viral load of HPV18. The 8-year absolute risk of CIN3+ in women with HPV16-viral load ≥100.0 pg/ml was 30.2% (95% CI: 21.9-38.6%). Our results support that hrHPV genotyping during cervical cancer screening may help identify women at highest risk of CIN3+.

Diagnosis of 25 genotypes of human papillomaviruses for their physical statuses in cervical precancerous/cancerous lesions: a comparison of E2/E6E7 ratio-based vs. multiple E1-L1/E6E7 ratio-based detection techniques

Background

Cervical lesions caused by integrated human papillomavirus (HPV) infection are highly dangerous because they can quickly develop into invasive cancers. However, clinicians are currently hampered by the lack of a quick, convenient and precise technique to detect integrated/mixed infections of various genotypes of HPVs in the cervix. This study aimed to develop a practical tool to determine the physical status of different HPVs and evaluate its clinical significance.

Methods

The target population comprised 1162 women with an HPV infection history of > six months and an abnormal cervical cytological finding. The multiple E1-L1/E6E7 ratio analysis, a novel technique, was developed based on determining the ratios of E1/E6E7, E2/E6E7, E4E5/E6E7, L2/E6E7 and L1/E6E7 within the viral genome. Any imbalanced ratios indicate integration. Its diagnostic and predictive performances were compared with those of E2/E6E7 ratio analysis. The detection accuracy of both techniques was evaluated using the gold-standard technique “detection of integrated papillomavirus sequences” (DIPS). To realize a multigenotypic detection goal, a primer and probe library was established.

Results

The integration rate of a particular genotype of HPV was correlated with its tumorigenic potential and women with higher lesion grades often carried lower viral loads. The E1-L1/E6E7 ratio analysis achieved 92.7% sensitivity and 99.0% specificity in detecting HPV integration, while the E2/E6E7 ratio analysis showed a much lower sensitivity (75.6%) and a similar specificity (99.3%). Interference due to episomal copies was observed in both techniques, leading to false-negative results. However, some positive results of E1-L1/E6E7 ratio analysis were missed by DIPS due to its stochastic detection nature. The E1-L1/E6E7 ratio analysis is more efficient than E2/E6E7 ratio analysis and DIPS in predicting precancerous/cancerous lesions, in which both positive predictive values (36.7%-82.3%) and negative predictive values (75.9%-100%) were highest (based on the results of three rounds of biopsies).

Conclusions

The multiple E1-L1/E6E7 ratio analysis is more sensitive and predictive than E2/E6E7 ratio analysis as a triage test for detecting HPV integration. It can effectively narrow the range of candidates for colposcopic examination and cervical biopsy, thereby lowering the expense of cervical cancer prevention.

Electronic supplementary material

The online version of this article (doi:10.1186/s12967-014-0282-2) contains supplementary material, which is available to authorized users.

Synergistic effect of viral load and alcohol consumption on the risk of persistent high-risk human papillomavirus infection

PURPOSE

This prospective study aimed to examine the combined effect of viral load and alcohol consumption on the risk of persistent high-risk (HR) human papillomavirus (HPV) infection.

METHODS

Among women undergoing health screening between 2002 and 2011 at the National Cancer Center, 284 and 122 women with HR-HPV infection and cytological findings of low-grade squamous intraepithelial or lower-grade lesions were followed up for 1 and 2 years, respectively. Multivariate logistic regression analysis was performed, and the relative excess risk due to interaction (RERI) and synergy index (S) were calculated.

RESULTS

Among drinkers, the risks of 1-year (odds ratio [OR] 4.09, 95% confidence interval [CI] 2.05-8.18) and 2-year persistence (OR 8.08, CI 2.36-27.6) were significantly higher for high HPV loads than for low HPV loads; this association was not seen for non-drinkers. The risks for 1-year (OR 4.14, CI 1.89-9.05) and 2-year persistence (OR 6.61, CI 2.09-20.9) were significantly higher in subjects with a high HPV load who were also drinkers than in those who were non-drinkers. A high HPV load together with a longer drinking duration or higher alcohol consumption was associated with increased risks of 1-year (OR 3.07, CI 1.40-6.75 or OR 2.05, CI 0.87-4.83) and 2-year persistence (OR 6.40, CI 1.72-23.8 or OR 4.14, CI 1.18-14.6). The synergistic effect of alcohol consumption and HR-HPV load was stronger on the risk of 2-year persistence (RERI = 3.26, S = 2.38) than on the risk of 1-year persistence (RERI = 1.21, S = 1.63).

CONCLUSIONS

The synergistic effect of HR-HPV load and alcohol consumption was associated with the risk of HR-HPV persistence and was stronger for longer-term HR-HPV infection. Limiting alcohol consumption might be an important measure to prevent the development of cervical cancer in women with a high HR-HPV load.

Changes in type-specific human papillomavirus load predict progression to cervical cancer

Persistent high-risk human papillomavirus (HPV) infection is strongly associated with the development of high-grade cervical intraepithelial neoplasia or cancer (CIN3+). However, HPV infection is common and usually transient. Viral load measured at a single time-point is a poor predictor of the natural history of HPV infection. The profile of viral load evolution over time could distinguish HPV infections with carcinogenic potential from infections that regress. A case-cohort natural history study was set-up using a Belgian laboratory database processing more than 100,000 liquid cytology specimens annually. All cytology leftovers were submitted to real-time PCR testing identifying E6/E7 genes of 17 HPV types, with viral load expressed as HPV copies/cell. Samples from untreated women who developed CIN3+ (n = 138) and women with transient HPV infection (n = 601) who contributed at least three viral load measurements were studied. Only single-type HPV infections were selected. The changes in viral load over time were assessed by the linear regression slope for the productive and/or clearing phase of infection in women developing CIN3+ and women with transient infection respectively. Transient HPV infections generated similar increasing (0.21 copies/cell/day) and decreasing (−0.28 copies/cell/day) viral load slopes. In HPV infections leading to CIN3+, the viral load increased almost linearly with a slope of 0.0028 copies/cell/day. Difference in slopes between transient infections and infections leading to CIN3+ was highly significant (P < .0001). Serial type-specific viral load measurements predict the natural history of HPV infections and could be used to triage women in HPV-based cervical cancer screening.

High-risk human papillomavirus viral load and persistence among heterosexual HIV-negative and HIV-positive men

OBJECTIVES

High-risk human papillomavirus (HR-HPV) viral load is associated with HR-HPV transmission and HR-HPV persistence in women. It is unknown whether HR-HPV viral load is associated with persistence in HIV-negative or HIV-positive men.

METHODS

HR-HPV viral load and persistence were evaluated among 703 HIV-negative and 233 HIV-positive heterosexual men who participated in a male circumcision trial in Rakai, Uganda. Penile swabs were tested at baseline and 6, 12 and 24 months for HR-HPV using the Roche HPV Linear Array, which provides a semiquantitative measure of HPV shedding by hybridisation band intensity (graded: 1-4). Prevalence risk ratios (PRR) were used to estimate the association between HR-HPV viral load and persistent detection of HR-HPV.

RESULTS

HR-HPV genotypes with high viral load (grade:3-4) at baseline were more likely to persist than HR-HPV genotypes with low viral load (grade: 1-2) among HIV-negative men (month 6: adjPRR=1.83, 95% CI 1.32 to 2.52; month 12: adjPRR=2.01, 95% CI 1.42 to 3.11), and HIV-positive men (month 6: adjPRR=1.33, 95% CI 1.06 to 1.67; month 12: adjPRR=1.73, 95% CI 1.18 to 2.54). Long-term persistence of HR-HPV was more frequent among HIV-positive men compared with HIV-negative men (month 24: adjPRR=2.27, 95% CI 1.47 to 3.51). Persistence of newly detected HR-HPV at the 6-month and 12-month visits with high viral load were also more likely to persist to 24 months than HR-HPV with low viral load among HIV-negative men (adjPRR=1.67, 95% CI 0.88 to 3.16).

CONCLUSIONS

HR-HPV genotypes with high viral load are more likely to persist among HIV-negative and HIV-positive men, though persistence was more common among HIV-positive men overall. The results may explain the association between high HR-HPV viral load and HR-HPV transmission.

Anti-viral treatment and cancer control

Hepatitis B virus (HBV), hepatitis C virus (HCV), human papillomavirus (HPV), and Epstein-Barr virus (EBV) contribute to about 10-15 % global burden of human cancers. Conventional chemotherapy or molecular target therapies have been used to treat virus-associated cancers. However, a more proactive approach would be the use of antiviral treatment to suppress or eliminate viral infections to prevent the occurrence of cancer in the first place. Antiviral treatments against chronic HBV and HCV infections have achieved this goal, with significant reduction in the incidence of hepatocellular carcinoma in treated patients. Antiviral treatments for EBV, Kaposi's sarcoma-associated herpesvirus (KSHV), and human T-cell lymphotropic virus type 1 (HTLV-1) had limited success in treating refractory EBV-associated lymphoma and post-transplant lymphoproliferative disorder, KSHV-associated Kaposi's sarcoma in AIDS patients, and HTLV-1-associated acute, chronic, and smoldering subtypes of adult T-cell lymphoma, respectively. Therapeutic HPV vaccine and RNA-interference-based therapies for treating HPV-associated cervical cancers also showed some encouraging results. Taken together, antiviral therapies have yielded promising results in cancer prevention and treatment. More large-scale studies are necessary to confirm the efficacy of antiviral therapy. Further investigation for more effective and convenient antiviral regimens warrants more attention.