Detection of human papillomavirus 16 and 18 DNA in epithelial lesions of the lower genital tract by in situ hybridization and polymerase chain reaction: cervical scrapes are not substitutes for biopsies

Human papillomavirus-16 prevalence in gingival tissue and its association with periodontal destruction: a case-control study

BACKGROUND

Human papillomavirus (HPV)-16 is detected in normal oral mucosa and several oral lesions, including squamous cell carcinoma, condyloma acuminatum, verruca vulgaris, focal epithelial hyperplasia, and periodontal diseases. It was hypothesized that HPV may be involved in periodontal breakdown and that periodontal tissue acts as a reservoir for the virus. Therefore, in this study, the prevalence of HPV-16 in the gingival tissue of Brazilians with periodontal health or disease is investigated.

METHODS

Fifty-six gingival samples from subjects with chronic periodontitis, 26 samples from subjects with gingivitis, and 22 samples from subjects with healthy peridontium were analyzed. Total DNA was extracted, and the presence of HPV-16 was assessed using a real-time polymerase chain reaction. Positive and negative controls were included in the reactions.

RESULTS

HPV-16 was not detected in any of the 104 gingival samples evaluated; therefore, this virus showed no association with periodontal disease in this study.

CONCLUSION

In the population studied, HPV-16 may not have participated in the pathogenesis of chronic periodontitis, and the gingival tissue did not act as a reservoir for this virus.

Age-specific prevalence of infection with human papillomavirus in females: a global review

PURPOSE

Global data on age-specific prevalence of human papillomavirus (HPV) infection overall, and for high-risk HPV types 16 and 18, are essential for the future implementation of HPV prophylactic vaccines for cervical cancer prevention.

METHODS

A systematic review of peer-reviewed publications was conducted to summarize worldwide data on genital HPV-DNA prevalence in women. Studies with clear descriptions of polymerase chain reaction or hybrid capture detection assays were included.

RESULTS

A total of 346,160 women were included in 375 studies. Of 134 studies with age-stratified HPV prevalence data (116 low sexual risk populations, 18 high sexual risk populations), over 50% were from Europe and the Middle East (38%) and North America (19%), with smaller proportions from Asia and Australia (21%), Central and South America (11%), and Africa (10%). Across all geographical regions, data on HPV prevalence were generally limited to women over 18 years of age. Consistently across studies, HPV infection prevalence decreased with increasing age from a peak prevalence in younger women (< or =25 years of age). In middle-aged women (35-50 years), maximum HPV prevalence differed across geographical regions: Africa (approximately 20%), Asia/Australia (approximately 15%), Central and South America (approximately 20%), North America (approximately 20%), Southern Europe/Middle East (approximately 15%), and Northern Europe (approximately 15%). Inconsistent trends in HPV prevalence by age were noted in older women, with a decrease or plateau of HPV prevalence in older ages in most studies, whereas others showed an increase of HPV prevalence in older ages. Similar trends of HPV 16 and/or 18 prevalence by age were noted among 12 populations with available data.

DISCUSSION

Genital HPV infection in women is predominantly acquired in adolescence, and peak prevalence in middle-aged women appears to differ across geographical regions. Worldwide variations in HPV prevalence across age appear to largely reflect differences in sexual behavior across geographical regions. Further studies of HPV prevalence in adolescents are needed for all geographic regions.

Utilidad de la detección del virus del papiloma humano de alto riesgo mediante Hybrid Capture II® en mujeres con citologías anormales del cuello uterino

INTRODUCTION

The objectives of the study were to investigate the usefulness of high-risk human papillomavirus (HR-HPV) detection in women with abnormal pap-smears as an adjunct to screening by cervical cytology, and to determine the viral load distribution according to the histological grade of the lesions.

METHODS

A total of 75 women were referred for cytological study of atypical cells of unknown origin (ASCUS), low-grade squamous intraepithelial lesions (LG-SIL) or high-grade squamous intraepithelial lesions (HG-SIL). All patients underwent colposcopy, histological study and HR-HPV detection using the Hybrid Capture II test.

RESULTS

In the pap-smear studies, HR-HPV was detected in 31.2% of women with ASCUS and 65.7% with LG-SIL. Histological examination showed HR-HPV in 46.4% of women without lesions, 69.5% of those with LG-SIL and 75% with HG-SIL. Negative predictive values for HG-SIL in women with cytological diagnoses of ASCUS and LG-SIL were 81.8% and 92.3%, respectively. Percentages of infection with high viral load significantly increased in accordance with the histological grade.

CONCLUSIONS

The Hybrid Capture II test can be useful for the management of women with cytological evidence of ASCUS because of the low prevalence of HR-HPV infection and the high negative predictive value for HG-SIL. The usefulness in women with a cytological diagnosis of LG-SIL is limited due to the high prevalence of HR-HPV infection. High viral load can be a risk factor for the development of premalignant cervical lesions.

Prevalence of human papillomavirus types in women with pre-neoplastic and neoplastic cervical lesions in the Federal District of Brazil

As a contribution to the public health authorities in planning prophylactic and therapeutic vaccine strategies, we describe the prevalence of human papillomavirus (HPV) types in women presenting abnormal cytological results in Pap smear screening tests in the Federal District, Central Brazil. We studied 129 cervical scraping samples from women whose cytological tests showed either pre-neoplastic or neoplastic lesions. Amplification of HPV DNA was performed by polymerase chain reaction using consensus primers MY09 and MY11 followed by identification of isolates by restriction fragment length polymorphism. We detected HPV DNA in 62% of the samples, including HPV-16 in 43.8%, HPV-58 in 12.5%, HPV-31 in 10%, HPV-53 in 6.3%, each of HPV-18 and HPV-33 in 3.8% of the isolates. Other types (HPV-35, -52, -66, -CP8304, -6, -11, and -CP8061) were less frequent (= or < 2.5% each). The prevalence of HPV-58 was relatively higher in this population than in data in South America, but similar to results obtained in other studies in Latin America, Europe, and Eastern Asia. Case-control studies need to be carried out to establish the association between the prevalence of HPV types specially the less frequent high-risk types and cervical cancer.

Is human papillomavirus testing of value in clinical practice?

The objective of this review was to evaluate the current status of human papillomavirus testing in predicting the presence of high-grade or invasive disease in the cervix in women with Papanicolaou smears reported as atypical squamous cells of undetermined significance (ASCUS) or low-grade squamous intraepithelial lesion. This is a review of many of the studies already published evaluating the utility of human papillomavirus testing as part of the triage for patients whose Papanicolaou smears were reported as ASCUS or low-grade squamous intraepithelial lesion. Two triage approaches for follow-up of such patients are presented, and recommendations are made as to which is most cost-effective and safe. Data related to human papillomavirus testing were obtained with both currently available commercial kits for detection of high-risk human papillomavirus and the polymerase chain reaction. There was variation in results reported, possibly related to populations studied. The approach to management by cytologic screening and colposcopy, when indicated, appeared over the long term to be equal to human papillomavirus testing. In our opinion current human papillomavirus testing is of little clinical use to the practitioner. Its use should be limited to appropriately designed and implemented research studies.

In situ hybridization and its diagnostic applications in pathology

In situ hybridization (ISH) is a technique by which specific nucleotide sequences are identified in cells or tissue sections. These may be endogenous, bacterial or viral, DNA or RNA. On the basis of research applications, the technique is now being translated into diagnostic practice, mainly in the areas of gene expression, infection and interphase cytogenetics. Diagnostic applications are most often based on short nucleotide sequences (oligomers) labelled with non-isotopic reporter molecules, and sites of binding may be localized by histochemical or immunohistochemical methods. The technique can be applied to routinely fixed and processed tissues; with some targets, it is even possible to obtain hybridization in autopsy material. ISH has been used to detect messenger RNA (mRNA) as a marker of gene expression, where levels of protein storage are low; for example, to confirm an endocrine tumour as the source of excess hormone production. Its application in infectious diseases has to date been mainly in viral infections, such as the typing of human papillomavirus (HPV) or the detection of Epstein-Barr virus by the presence of small nuclear RNAs (EBERs). The expression of mRNAs for histone proteins has been used to detect cells in S phase, and related methods may be applied to detect apoptotic cells. Using probes to chromosome-specific sequences, it is possible to detect aneuploidy, and to document changes in specific chromosomes, which may have prognostic significance in some tumours, such as B-cell chronic lymphatic leukaemia. Using sequence-specific probes, translocations can be identified, such as the t(11;12) of Ewing's sarcoma. This review presents an outline of the technique of in situ hybridization and discusses areas of current and potential diagnostic application.

Improved detection of human papillomavirus infection in genital intraepithelial neoplasia in human immunodeficiency virus positive (HIV +) women by polymerase chain reaction-in situ hybridization

The prevalence of genital human papillomavirus (HPV) infection was evaluated in 30 consecutive human immunodeficiency virus (HIV) + women by polymerase chain reaction (PCR)-in situ hybridization (ISH) on paraffin-embedded tissue sections and compared with that found with standard ISH. Biopsies were removed from normal or neoplastic areas in the cervix, vagina, and vulva, and ISH was performed with biotinylated or fluorescein isothiocyanate genomic DNA probes. One probe was used for HPV screening and others for HPV typing (types 6, 11, 16, 18, 31, and 33). Sequences were amplified by the "hot-start" PCR method and followed by standard ISH. Among the 30 HIV + women, 90% scored HPV + in one or several locations by PCR-ISH, whereas only 67% were positive by ISH. Oncogenic HPV types were found in 63% by PCR-ISH and in only 43% by ISH. The same HPV types detected by standard ISH were also recognized by PCR-ISH, but with the latter the signal was amplified. Moreover, some HPV types were found with PCR-ISH but not by ISH. We conclude that PCR-ISH is a valuable and sensitive method for specific detection of HPV.

Detection of human papillomavirus in cervical scrapings by in situ hybridization and the polymerase chain reaction in relation to cytology

A gynaecological out-patient population consisting of 200 patients aged 19-43 years (mean age 34.2 years) was screened for the presence of human papillomavirus (HPV) by the polymerase chain reaction and in situ hybridization on cervical scrapings. A novel method was applied for the detection of HPV in cervical cells by embedding them in a paraffin block before in situ hybridization was performed. This technique resulted in well preserved cytological morphology, easy performance and economy of probes. In eight of the 200 patients (4%), human papillomavirus DNA was revealed by the polymerase chain reaction. Subtyping revealed the presence of HPV serotype 16 DNA in three of these patients. In one patient HPV serotype 18 DNA was also present. The in situ hybridization assay was able to detect all those cases with a specific HPV serotype infection.