Prevalence of papillomavirus in Brazil: a systematic review protocol

HPV 18 variants in women with cervical cancer in Northeast Brazil

BACKGROUND

Human Papillomavirus (HPV) is the main etiological factor for the development of cervical cancer. HPV 18 is the second most frequent type, accounting for up to 65% of all cases. HPV intratypic variation may influence the potential for progression to invasive cancer. The aim of this study was to evaluate the prevalence of human papillomavirus 18 intratypic variants in cervical cancer samples from women in the state of Maranhão, Brazil.

METHODS

The study included 118 women over 18 years of age with a diagnosis of cervical cancer. Tumor fragments were collected and subjected to DNA extraction and Polymerase Chain Reaction (PCR) for HPV detection using the PGMY09/11 and GP+5/6 primers. Positive samples were submitted to automated sequencing for viral genotyping. To determine the HPV 18 lineages, positive samples were submitted to PCR, using specific primers to amplify the LCR and E6 regions of HPV 18 virus.

RESULTS

HPV was present in 88 women (73.3%). Of those, 48 (54%) were HPV 16, the most prevalent, followed by 12 (13.6%) HPV 18. Histologically, squamous cell carcinoma was predominant (79.1%). Among the HPV 18 variants identified, 10 (80%) belonged to lineage A, and sublineages A1, A2, A3, and A4. Two (29%) HPV 18 B variant was also detected, with the sublineages B1 and B2. In this study, the C variant was not found. There was no statistically significant association between the HPV 18 lineages found and sociodemographic and lifestyle variables (p > 0.05).

CONCLUSIONS

A higher frequency of HPV 16 and 18 were found in women with cervical cancer in the state of Maranhão, Brazil, with a high prevalence of the lineage A among women with HPV 18.

Prevalence and Genotyping of HPV in Oral Squamous Cell Carcinoma in Northern Brazil

Highly oncogenic human papillomavirus (HPV) is well known to be associated with and a risk factor for various types of oral carcinomas such as oral squamous cell carcinoma (OSCC). The aim of this study was to evaluate and describe the HPV-induced OSCC prevalence and genotyping in the city of Belém, northern Brazil. This cross-sectional study features 101 participants who attended an oral pathology referral center in a dental college looking for diagnoses of oral lesions (OL). After signing the consent term and meeting the inclusion criteria, all participants went through a sociodemographic and epidemiological questionnaire. Then, OL were collected by excisional or incisional biopsy depending on OL size; after that, OL tissues were preserved in paraffin blocks to histopathological diagnoses. Afterwards, paraffin blocks were divided into benign and malignant/premalignant lesions based on the classification of potentially malignant disorders of the oral and oropharyngeal mucosa. Then, the paraffin blocks had DNA extraction performed by the ReliaPrep FFPE gDNA Miniprep method in order to identify HPV DNA of high oncogenic risk and low oncogenic risk. Then, the viral DNA was amplified and typed using the Inno-Lipa genotyping Extra II method, and the collected data were analyzed by Chi-square and G-tests. In total, 59/101 (58.4%) OL were malignant/premalignant lesions, of which OSCC was the most prevalent with 40/59 (67.7%) and 42/101 (41.6%) benign lesions. The most common area of OL incidence was upper gingiva 46/101 (45.5%). Regarding HPV DNA detection, approximately 27/101 (26.7%) had positive results; of these, 17/59 (28.8%) were malignant/premalignant lesions, and the most prevalent genotypes detected were 16, 18, 52 and 58, while among benign lesions, 10/42 (66.6%) had HPV-positive results, and the most prevalent genotypes detected were 6, 11 and 42. Age range was the only risk factor with a significant association between HPV and OSCC presence (p-value: 0.0004). A correlation between OSCC and oral HPV among analyzed samples could not be demonstrated in our small cohort.

University Students' Knowledge about the Relation between Human Papillomavirus (HPV) and Head and Neck and Oral Cancers

INTRODUCTION

Human papillomavirus (HPV) causes the most common sexually transmitted infection (STI) in the world. It affects people regardless of gender and age, causing genital warts and cancer.

OBJECTIVE

To evaluate university students' knowledge of HPV and its relationship with head and neck and oral cancers.

METHODS

This is a cross-sectional study using an online questionnaire administered to undergraduate students at a public university (n=335).

RESULTS

In total, 69.3% of the participants were unaware of the relationship between HPV and head and neck cancers and 34.6% claimed that HPV may not cause oral cancer.  The chances of knowing about the relationship of HPV with head and neck cancers were significant for participants who knew that HPV could be asymptomatic (OR = 9.9; p = 0.029), that might cause genital warts in men (OR = 4.0; p = 0.015), and those aged 24 years or older (OR = 1.9; p = 0.021). However, undergraduate students in the field of health and medicine (OR = 0.419; p = 0.002), who had sex at least twice a week (OR = 0.471; p = 0.017), and were unaware of the target public for the HPV vaccine (OR: 0.222, p<0.001) were less likely to know about the relationship. Students who knew of the relationship between HPV and female (OR = 3.6; p = 0.010) and male genital warts (OR = 3.0; p = 0.005) or were immunized (OR = 1.8; p = 0.020) were more likely to understand the viral interaction with oral cancer. Those who were unaware of the population eligible for HPV vaccine (OR = 0.493; p = 0.017) also showed gaps in their knowledge of this relationship.

CONCLUSION

Our findings showed that there were limitations in the knowledge about HPV, its vaccine, and its relationship with head and neck and oral cancers.

A Nationwide Evaluation of the Prevalence of Human Papillomavirus in Brazil (POP-Brazil Study): Protocol for Data Quality Assurance and Control

BACKGROUND

The credibility of a study and its internal and external validity depend crucially on the quality of the data produced. An in-depth knowledge of quality control processes is essential as large and integrative epidemiological studies are increasingly prioritized.

OBJECTIVE

This study aimed to describe the stages of quality control in the POP-Brazil study and to present an analysis of the quality indicators.

METHODS

Quality assurance and control were initiated with the planning of this nationwide, multicentric study and continued through the development of the project. All quality control protocol strategies, such as training, protocol implementation, audits, and inspection, were discussed one by one. We highlight the importance of conducting a pilot study that provides the researcher the opportunity to refine or modify the research methodology and validating the results through double data entry, test-retest, and analysis of nonresponse rates.

RESULTS

This cross-sectional, nationwide, multicentric study recruited 8628 sexually active young adults (16-25 years old) in 119 public health units between September 2016 and November 2017. The Human Research Ethics Committee of the Moinhos de Vento Hospital approved this project.

CONCLUSIONS

Quality control processes are a continuum, not restricted to a single event, and are fundamental to the success of data integrity and the minimization of bias in epidemiological studies. The quality control steps described can be used as a guide to implement evidence-based, valid, reliable, and useful procedures in most observational studies to ensure data integrity.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

RR1-10.2196/31365.

Prevalence of human papillomavirus (HPV) in Brazil: A systematic review and meta-analysis

OBJECTIVES

This study aimed to estimate the prevalence of genital, anal and oral HPV infection in Brazil through systematic review and meta-analysis.

METHODS

We searched EMBASE, LILACS, MEDLINE, Web of Science and SciELO from inception to December 2018. Original research articles that assessed the prevalence of genital (i.e., cervical, penile), anal and oral HPV infection in Brazil were selected in pairs by independent authors. No sex, age, HPV vaccination, language or date restrictions were applied. HPV prevalence was estimated and stratified according to risk factors population and by geographic area throughout the country. The study prevalence was pooled using a random effects model. Analysis was performed using R (version 3.5.2), packages meta version 4.9-4 and metaphor 2.0-0. This review is registered on PROSPERO under protocol number CRD42016032751.

RESULTS

We identified 3,351 references. After the screening process, 139 of them were eligible for this systematic review (57,513 total participants). Prevalence of cervical HPV was 25.41% (95% CI 22.71-28.32). Additionally, prevalence was 36.21% (95% CI 23.40, 51.33) in the penile region, 25.68% (95%CI 14.64, 41.04) in the anal region, and 11.89% (95%CI 6.26, 21.43) in the oral region. Subgroup analysis showed prevalence in each anatomic site was higher in high-risk populations.

CONCLUSION

The prevalence of HPV is high in the Brazilian population and varies by population risk and anatomic body site, with lower rates in the oral cavity compared to that in the cervical, penile and anal region. Studies on HPV have primarily been developed to evaluate infection and cancer in the cervical region. There is a profound lack of HPV data in many geographic regions of Brazil and for different anatomic sites.

Oncogenic high-risk human papillomavirus in patients with full denture

Human Papillomavirus (HPV) has considerable tropism for epithelial and mucosal tissues and can therefore be found in several anatomical sites, including the oral cavity. This study aimed to investigate the presence of HPV-DNA and the most frequent viral types in patients using full dentures, compare to patients not using full dentures and to associate its presence with socio-epidemiological and behavioral factors. The study consisted of 90 patients with or without full dentures at the time of collection, treated at a public dental clinic. The samples were obtained by exfoliating the oral cavity, and analyzed for HPV-DNA using the nested PCR with PGMY09/11 (450-bp), and general primers GP5+/GP6+ (150-bp). Genotyping was performed by specific-type PCR to HPV 6, 11, 16, 18, 31, 33, and 45; and Restriction Fragment Length Polymorphism (RFLP). Pearson's Chi-square test (x 2 ) or Fisher's exact test were applied and significant variables in these tests were analyzed by multinomial logistic regression analysis to estimate odds ratio (OR). HPV-DNA was detected in 27.7% of samples and, among those obtained from patients using full dentures, positivity for HPV-DNA was 41.9% (p = 0.025). The most frequent viral types were low-risk HPV 6 and 11, and high-risk HPV 31 and 45. Patients who used full dentures had an odds ratio of 2.1 to be positive for HPV DNA. Our results indicate the need for periodic dental follow-up of patients with full dentures in order to preserve the basic conditions of oral health, and also to monitor the appearance of lesions with malignant potential.

Tityus serrulatus Scorpion Venom Induces Apoptosis in Cervical Cancer Cell Lines

Cervical cancer (CC) is classified as the fourth most common type of cancer in women worldwide and remains a serious public health problem in many underdeveloped countries. Human papillomavirus (HPV), mainly types 16 and 18, has been established as a precursory etiologic agent for this type of cancer. Several therapeutic attempts have been studied and applied, aiming at its control. However, not only do classical treatments such as chemotherapies and radiotherapies target tumor cells, but also they cause damage to several healthy cells. For these reasons, the search for new biologically active chemotherapeutic components is of great importance. In this study, we investigated the effect of Tityus serrulatus scorpion venom (TsV) on CC lines. There are very few studies exploring venom of scorpions, and, to our knowledge, no study has been conducted using the venom of the scorpion TsV for treatment of cervical cancer lines. After challenge with TsV, the MTT assay demonstrated cytotoxic effect on HeLa line. Similarly, the cell death process in HeLa analyzed by flow cytometry suggests death via caspase, since the pan-caspase inhibitor z-VAD-fmk significantly reduced the apoptotic response to the treatment. These results suggest that venom of TsV can be a potential source for the isolation of effective antiproliferative and apoptotic molecules in the treatment of CC.

POP-Brazil study protocol: a nationwide cross-sectional evaluation of the prevalence and genotype distribution of human papillomavirus (HPV) in Brazil

INTRODUCTION

Human papillomavirus (HPV) is associated with the development of genital warts and different types of cancer, including virtually all cervical cancers and a considerable number of penile, anal and oropharyngeal cancers. Data regarding the prevalence of HPV infection in Brazil are limited and fragmented. We aim to determine HPV prevalence in sexually active women and men aged 16-25 years and to investigate regional differences in virus prevalence and types.

METHODS AND ANALYSIS

This is a nationwide, multicentric, cross-sectional, prospective study that will include participants aged 16-25 years from all Brazilian capital cities. Recruitment will occur in primary health units by trained health professionals who will be responsible for collecting biological samples and interviewing the volunteers. After signing informed consent, all participants will answer a questionnaire that will collect sociodemographic and behavioural data. All samples will be processed in a certified central laboratory, and strict quality control will be performed by many different procedures, including double data entry, training and certification of primary care health professionals responsible for data collection, simulation of interviews, and auditing and monitoring of visits. The sample size will be standardised based on the population distribution of each capital using SAS and R statistical software.

ETHICS AND DISSEMINATION

The project was approved by the research ethics committee of the main institution and the corresponding ethics committees of the recruitment sites. This will be the first Brazilian nationwide study to determine overall HPV prevalence and to examine regional differences and social, demographic and behavioural factors related to HPV infection. Critical analysis of the study results will contribute to epidemiological knowledge and will set a baseline for future evaluation of the impact of the National HPV Vaccination Program.