Demonstration of multiple HPV types in normal cervix and in cervical squamous cell carcinoma using the polymerase chain reaction on paraffin wax embedded material

Prevalence of HPV-DNA and E6 mRNA in lung cancer of HIV-infected patients

HIV-infected individuals could be at a greater risk for developing lung cancer than the general population due to the higher prevalence in the former of human papillomavirus (HPV) in the oral cavity and higher smoking rates. Our aim was to assess HPV prevalence and E6 viral oncogene transcription in lung cancer samples from HIV-infected individuals. This was a single-center, retrospective study of a cohort of HIV-1-infected patients diagnosed with and treated for lung cancer. Pathological lung samples archived as smears or formalin-fixed paraffin-embedded blocks were subjected to HPV genotyping, detection of human p16 protein and assessment for HPV E6 mRNA expression. Lung cancer samples from 41 patients were studied, including squamous cell carcinoma (32%), adenocarcinoma (34%), non-small cell cancer (27%), and small cell cancer (7%). HPV DNA was detected in 23 out of 41 (56%, 95% CI 41–70%) of samples and high-risk (HR)-HPV types were detected in 16 out of 41 (39%, 95% CI 26–54%), HPV-16 being the most prevalent [13/16 (81.3%, 95% CI 57.0–93%]. In samples with sufficient material left: expression of p16 was detected in 3 out of 10 (30%) of HR-HPV DNA-positive tumors and in 3 out of 7 (43%) of the negative ones; and E6 mRNA was detected in 2 out of 10 (20%) of HPV-16-positive samples (squamous lung cancers). These two patients had a background of a previous HPV-related neoplasia and smoking. HR-HPV DNA detection was prevalent in lung cancers in HIV-infected patients. However, viral oncogene expression was limited to patients with previous HPV-related cancers.

High Human Papillomavirus DNA loads in Inflammatory Middle Ear Diseases

Background. Previous studies reported human papillomaviruses (HPVs) in middle ear tumors, whereas these viruses have been poorly investigated in chronic inflammatory middle ear diseases. We investigated HPVs in non-tumor middle ear diseases, including chronic otitis media (COM). Methods. COM specimens (n = 52), including chronic suppurative otitis media (CSOM) (n =38) and cholesteatoma (COMC) (n = 14), as well as normal middle ear (NME) specimens (n = 56) were analyzed. HPV sequences and DNA loads were analyzed by quantitative-PCR. HPV genotyping was performed by direct sequencing. Results. HPV DNA was detected in 23% (12/52) of COM and in 30.4% (17/56) of NME (p > 0.05). Specifically, HPV DNA sequences were found in 26.3% (10/38) of CSOM and in 14.3% (2/14) of COMC (p > 0.05). Interestingly, the HPV DNA load was higher in COMC (mean 7.47 copy/cell) than in CSOM (mean 1.02 copy/cell) and NME (mean 1.18 copy/cell) (P = 0.03 and P = 0.017 versus CSOM and NME, respectively). HPV16 and HPV18 were the main genotypes detected in COMC, CSOM and NME. Conclusions. These data suggest that HPV may infect the middle ear mucosa, whereas HPV-positive COMCs are associated with higher viral DNA loads as compared to NME.

Human papilloma virus 16/18 genotypes in patients with squamous cell carcinoma of cervix in northeast Iran

Background:

A relation has been established between infection with high-risk types of human papilloma virus (HPV) and development of cervical cancer. To estimate the risk of HPV infection for cervical malignancies, we conducted a case-control study in northeast Iran.

Materials and Methods:

This study was carried out on 123 paraffin embedded blocks with exact diagnosis of squamous cell carcinoma (SCC). A total of 100 cervical tissue specimens with normal histopathology product of hysterectomy were also used as control. Both groups were tested for the presence of HPV DNA and HPV 16/18 subtypes using PCR assay.

Results:

Large non-keratinising subtype of cervical carcinoma was the most frequent one (62.6%), followed by keratinising and small cell subtypes (27% and 10%, respectively). Overall prevalence of HPV infection in SCC of cervix was 34.2% (42 out of 123 cases). HPV 16 was the most common type in this group (21 cases, 17.1%), followed by HPV 18 (16 cases, 13%) and other subtypes (5 cases, 4.1%). In this study, overall prevalence of HPV infection in control group was 12% (including 3% HPV 16; 5% HPV 18 and 4% other subtypes).

Conclusion:

Although association of HPV 16/18 and SCC of cervix was relatively higher than control group, compared with the previous study, the association between cervical SCC and HPV infection was significantly lower in our study; and possibly, the other risk factors play a major role in carcinogenesis of cervical carcinoma in this region.

Next-generation sequencing for simultaneous determination of human papillomavirus load, subtype, and associated genomic copy number changes in tumors

Human papillomavirus (HPV) infection in cases of squamous cell carcinoma of the oropharynx is a powerful predictive and prognostic biomarker. We describe how the use of next-generation sequencing can provide a novel method for the detection of HPV in DNA isolated from formalin-fixed paraffin-embedded tissues. Using this methodology in a cohort of 44 head and neck tumors, we identified the samples that contained HPV sequences, the viral subtype involved, and a direct readout of viral load. Specificity of HPV detection by sequencing compared to traditional detection methods using either PCR or p16 immunohistochemistry was 100%. Sensitivity was 50% when either compared to PCR [confidence interval (CI) = 29% to 71%] or 75% when compared to p16 (CI = 47% to 91%). In addition, we demonstrate the ability of next-generation sequencing to detect other HPV subtypes that would not have been detected by traditional methods, and we demonstrated the ability to apply this method to any tumor and any virus in a panel of eight human cancer cell lines. This methodology also provides a tumor genomic copy number karyogram, and in the samples analyzed here, a lower level of chromosome instability was detected in HPV-positive tumors compared to HPV-negative tumors, as observed in previous studies. Thus, the use of next-generation sequencing for the detection of HPV provides a multiplicity of data with clinical significance in a single test.

An association of human papillomaviruses low risk and high risk subtypes with skin tag

OBJECTIVES

Human papillomavirus (HPV) infections are related to the genesis of various benign lesions and some malignant tumors, but no clear relationship has been identified so far between the subtypes of HPV and skin tag.

MATERIALS AND METHODS

The present case-control study was designed to detect the existence of low risk and high risk HPV types in lesions of 50 patients with skin tag (case group) and normal skin around the melanocytic nevus of 30 patients (control group), using PCR.

RESULTS

All of the samples were negative for HPV subtypes, except two samples in control group which were positive for high risk HPV. There was no significant relationship between the HPV subtypes and skin tag.

CONCLUSION

There is no association between skin tag and low risk and high risk human papillomaviruses.

Papillary squamous cell carcinoma of the cervix in Uganda: a report of 20 cases

BACKGROUND

Non-glandular papillary carcinoma of the cervix are uncommon tumours. In Uganda where cervical carcinoma is very common, no cases of papillary squamous cell carcinoma of the cervix has been reported.

OBJECTIVES

To ascertain the occurrence and describe the clinicopathological features of papillary squamous cell carcinoma of the cervix in Uganda.

STUDY DESIGN

Retrospective review of histologically diagnosed cases of squamous cell carcinoma of cervix with papillary structures.

METHODS

Retrospective review of cases of cervical carcinoma diagnosed in the Pathology Department, Makerere University from 1968 to 1973 was done. Cases with features of squamous differentiation and forming papillary pattern were then selected.

RESULTS

Twenty cases were encountered and the ages of the patients ranged from 22 to 70 years (mean 46.6 years). Histologically, the tumours had thin to broad fibrovascular cores covered by multilayered squamous epithelium. In five cases, there were areas with very delicate fibrovascular cores covered by monolayered epithelial cells.

CONCLUSION

The results of this study show that in Uganda, papillary squamous cell carcinoma of the cervix does occur and is predominantly a disease of older women. The results also confirm that papillary squamous cell carcinoma is a distinct subtype with some variants, and support the hypothesis that squamous cell carcinoma of the cervix is heterogeneous group of tumuors.

The causal relation between human papillomavirus and cervical cancer

The causal role of human papillomavirus infections in cervical cancer has been documented beyond reasonable doubt. The association is present in virtually all cervical cancer cases worldwide. It is the right time for medical societies and public health regulators to consider this evidence and to define its preventive and clinical implications. A comprehensive review of key studies and results is presented.

High-risk human papillomavirus types and squamous cell carcinoma in patients with respiratory papillomas

Respiratory papillomas (RPs) are benign, virally induced tumors of the larynx and respiratory epithelium that may obstruct the airway and tend to recur frequently. RPs are thought to be the result of infection with the human papillomaviruses (HPVs) types 6 and 11. We surveyed archival RP specimens to determine whether there were correlations of HPV type with patient characteristics or clinical course. Paraffin-embedded papilloma specimens of 45 different patients were analyzed. We assessed HPV types using the polymerase chain reaction with E6 consensus primers, hybrid capture assays (high or low risk), and dot blot hybridization of generic E6 PCR products with E6 type-specific oligonucleotide probes. The presence and type of HPV were correlated with patient data from a retrospective chart review. We found that RPs may have either low- or high-risk HPV types and some contain multiple HPV types. Respiratory infection with high-risk HPV apparently introduces a long-term risk of squamous cell carcinoma development, even in the absence of conventional cofactors. Low-risk HPV infection may also act in association with these cofactors to promote carcinogenesis. Our data also show a racial imbalance in RP that may indicate a difference in genetic resistance and/or susceptibility to HPV infection and the development of RP.

In situ amplification of the Epstein-Barr virus genome in cell suspensions

Epstein-Barr virus (EBV) is distributed widely throughout the world. Apart from a association with two geographically-restricted malignancies (Burkitt's lymphoma and nasopharyngeal carcinoma), EBV is thought to be implicated in the etiology of B-cell lymphoma in immunocompromised individuals. In these patients, monitoring the viral load in serum can provide useful information on the timing of the instigation of antiviral therapy, i.e. as soon as a rise is detected. PCR technology, owing to its high sensitivity, is used frequently in such situations. In order to gain further insight into the nature of the peripheral blood cells carrying the viral genome on a cell-by-cell basis, an in situ amplification technique was developed as a model using two cell lines growing in suspension, with the aim of distinguishing between EBV-positive and EBV-negative cells. Preliminary experiments were undertaken subsequently on clinical samples from patients with infectious mononucleosis and patients with lymphoma indicating that this technique might be useful clinically.

Human papillomavirus in corneal and conjunctival carcinoma

PURPOSE

To investigate the role of human papillomavirus (HPV) types, 6, 11, 16 and 18 in corneal and conjunctival carcinoma, we examined 88 dysplastic corneal and conjunctival specimens and 66 controls that had been formalin-fixed and paraffin-embedded.

METHODS

Sections were graded for histological abnormality by light microscopy and the presence of HPV DNA was determined by polymerase chain reaction using LI consensus primers.

RESULTS

Human papillomavirus DNA was detected in 34 (39%) dysplasias and in five (7.5%) controls. Of dysplasias that were HPV-positive, 20 (59%) contained either types 16 or 18, 13 (38%) contained only types 6/11, while combinations of HPV types were present in 11 (32%). A histological correlation was found with HPV positivity (all genotypes) and unusually large ('epithelioid') dysplastic cells.

CONCLUSION

The present study demonstrates a lower incidence of HPV in corneal and conjunctival carcinoma than previously reported, but shows an unexpectedly high incidence of HPV 6/11 in conjunctival carcinomas.

Prevalence of HPV DNA in cervical lesions in patients from Ecuador and Japan

Cervical cancer is about 6 times more frequent in Ecuador than in Japan. We investigated the association between infection by the human papillomavirus (HPV) and the genesis of cervical cancer in specimens of lesions of the cervical epithelium obtained from patients in Ecuador and Japan. We also examined the results of HPV DNA detection and typing by the polymerase chain reaction (PCR) performed under the same technical conditions in areas with differing rates of cervical cancer. Purified tissue DNA from paraffin-embedded samples was amplified by PCR with universal and type-specific primers. HPV DNA was detected in 8 (20%) of 40 normal cervical epithelial samples from Ecuadorian patients, 19 (45%) of 42 low-grade squamous intraepithelial lesions (LSIL), 16 (50%) of 32 high-grade squamous intraepithelial lesions (HSIL), and 38 (81%) of 47 invasive squamous cell carcinomas (SCC) compared with 3 (10%) of 30 normal cervical specimens from Japanese patients, 107 (51%) of 210 HSILs, and 45 (71%) of 63 SCCs. The prevalence of HPV types 16 and 18 rose significantly with increasing histological grade (p < 0.05). The prevalence of HPV DNA decreased with increasing age in both Ecuadorian and Japanese patients. The detection rate and type-specific distribution of HPV DNA were not correlated with geographic location. Findings suggest that risk factors associated with poverty and underdevelopment may influence the prevalence of HPV infection and the sequence of events after HPV infection culminating in cervical cancer. These factors may help to explain the differing geographic distribution of this disease.

Applications of the polymerase chain reaction (PCR) in diagnosis

This paper reports on three applications of the polymerase chain reaction (PCR) in the pathology laboratory, cystic fibrosis carrier status investigation, Staphylococcus aureus identification and HLA-DQ alpha tissue typing. Allele specific PCR was used to detect the common cystic fibrosis mutation (delta F508) in an Irish family. The genomic status of each member was shown to be either heterozygous (carrier) or homozygous (affected) for the mutation, based on the resolution of allelic amplifications in an agarose gel. Five staphylococci were subjected to PCR designed to amplify a 137 bp DNA fragment from the S. aureus protein A gene (spa). Four isolates gave a coloured "dot-blot" positive signal, the fifth was negative. In the final application the HLA-DQ alpha region was amplified using DNA obtained from four unrelated individuals. Amplified DNA was tissue typed in a reverse "dot-blot" format. All individuals had unique HLA-DQ alpha types. These examples have been chosen to demonstrate the versatility of this technique and to illustrate some of its potential applications.

The polymerase chain reaction in histopathology

Thanks to the advent of the polymerase chain reaction (PCR) molecular genetic study of histological samples is now a relatively straightforward task and the vast histopathology archives are now open to molecular analysis. In this review we outline technical aspects of PCR analysis of histological material and evaluate its application to the diagnosis and study of genetic, infectious and neoplastic disease. In addition, we describe a number of newly developed methods for the correlation of PCR analysis with histology, which will aid the understanding of the molecular basis of pathological processes.

Transitional cell carcinoma of the bladder: evaluation of the role of human papillomaviruses

OBJECTIVES

The study evaluated the conflicting results of the role of human papillomavirus (HPV) in the development of bladder carcinoma.

METHODS

We analyzed the frequency of HPV types 6, 11, 16, 18, and 33 by using polymerase chain reaction on formalin-fixed, paraffin-embedded specimens, from 75 cases of transitional cell carcinoma (TCC) of the bladder. Fifteen samples of normal urothelium adjacent to TCC (10) or from normal bladder obtained at autopsy (5) served as negative controls.

RESULTS

HPV type 16 deoxyribonucleic acid (DNA) was detected in 2 (2.7%) of the 75 cases of TCC and in none of the normal urinary bladder cases. The 2 patients with HPV type 16 were immunosuppressed after undergoing renal and cardiac transplantation.

CONCLUSIONS

These results strongly suggest that HPVs play a minor role in the development of TCC of the bladder in the general population, although they can act as oncogenic agents in predisposed patients, such as those who are immunosuppressed.

Nucleic acid amplification and infectious disease

Infectious organisms that have long eluded detection may now be easily identified using nucleic acid amplification techniques. Because nucleic acids are relatively stable, a wide range of samples, including paraffin-embedded fixed tissues, may be amplified. Infections by both RNA and DNA viruses and a variety of other organisms may be detected in both a prospective and retrospective fashion. Amplification techniques also may be used to detect bacterial toxins or type organisms for epidemiological purposes. However, the current lack of standardization between laboratories makes the interpretation of a negative or positive result hazardous in some instances, a problem that should be resolved with the evolution of the procedure.

Preservation of multiple oncogenic human papillomavirus types in recurrences of early-stage cervical cancers

OBJECTIVES

Our purpose was to determine the relationship between human papillomavirus genotypes contained in primary early stage cervical cancers and those contained in the respective recurrences.

STUDY DESIGN

Six early-stage cervical cancers that were considered cured by surgical extirpation subsequently recurred within 21 months of the original surgery. The primary tumors and the recurrences underwent polymerase chain reaction for human papillomavirus typing with confirmation of types performed by means of diagnostic restriction fragments.

RESULTS

All primary tumors and recurrences contained human papillomavirus, with all primary tumors positive for multiple types. The concordance rate between the primary tumors and recurrences for specific types was 73% (11/15). Among the highly oncogenic types 16 and 18 there was 100% concordance between primary and recurrent tumors.

CONCLUSIONS

Highly oncogenic types of human papillomavirus are preserved between primary tumors and their recurrences in cervical cancers. This further supports the role of oncogenic types in the maintenance of the malignant state and supports the clonogenic nature of cervical cancer recurrence.

Human papilloma viruses: a study of their prevalence in the normal larynx

The association of human papilloma viruses (HPV) with laryngopharyngeal squamous cell carcinoma is under investigation. The suitability of control tissue in the reported series, invariably obtained from histologically normal tissue adjacent to a squamous cell carcinoma or from patients with benign laryngopharyngeal disease, is questionable. The present study determined the prevalence of HPV in a series of normal larynges. Twelve autopsy larynges were collected. DNA was obtained by SDS proteinase K digestion. Evidence of HPV infection was documented by the polymerase chain reaction using oligonucleotide primers complementary to sequences in the E6 region of HPV types 11, 16 and 18. Four female and eight male larynges, mean age 65 years (SD = 16 years) were collected 72 hours postmortem (median value). HPV type 11 was isolated from three specimens. A 25 per cent prevalence rate for HPV 11 was found. No other HPV types were isolated.

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 (HPV) types 16 and 18 in 66 women with histologically documented lesions of the genital tract and 64 control cohorts were investigated. The efficacies of in situ hybridization and polymerase chain reaction (PCR) in detecting HPV 16 and 18 DNA were analyzed. In order to assess the usefulness of replacing biopsies with cervical scrapes, the two samples were compared by PCR. The prevalence rates of HPV infection by PCR were 59.1 and 10.9% in patients and controls, respectively. PCR was three times more sensitive than in situ hybridization (52.6 versus 17.8%). However, the need to improve PCR sensitivity by subsequent dot blot hybridization reduced one of the main advantages of PCR, i.e., expeditious diagnosis. Cervical scrapes were less sensitive than biopsies (13.6 versus 53%), although with four (6.1%) patients with intraepithelial neoplasias, HPV DNA was identified only by means of cervical scraping. We conclude that obtaining biopsy specimens and cervical scraping are complementary sampling procedures.

Prognostic significance of polymerase chain reaction detected human papillomavirus of tumors and lymph nodes in surgically treated stage IB cervical cancer

This study describes the prognostic role of polymerase chain reaction detected human papillomavirus (HPV) in Stage IB cervical cancer patients treated with radical hysterectomy and pelvic and paraaortic node dissection. All tumors were confined to the cervix and all margins and nodes were disease free. Twenty-one patients were analyzed: 6 patients recurred within 20 months of initial therapy, while 15 had no evidence of disease with a minimum follow-up of 36 months. Polymerase chain reaction (PCR) was performed on paraffin-block tissue of the hysterectomy specimen cervical tumor and lymph nodes. Oligonucleotide probes for HPV types 6, 11, 16, 18, 31, 33, and 35 were used with consensus primers for uncharacterized HPV types created from an L1 constant region. Control tissues were run with each tumor sample to assure against contamination. HPV type confirmation was performed using diagnostic restriction sites. HPV was detected in all cervical tumors. Recurring tumors were infected with multiple types of HPV in all 6 tumors versus only 5 of 15 nonrecurring tumors being multiply infected (P = 0.023). No tumor had HPV 6 or 11, and the incidence of HPV 16, 31, 33, and 35 was not significantly different for recurrent versus nonrecurrent groups. HPV 18 was found in 5 of 6 recurring cancers versus 1 of 15 nonrecurring tumors (P = 0.0029). PCR typing of the histologically negative nodes that had been obtained at radical hysterectomy was done in all 6 recurring patients and in 6 nonrecurring patients. The recurrent patients had a significantly higher incidence of lymph nodes positive for HPV DNA (71%) than the nonrecurring patients (35%) (P = 0.0047). These observations suggest that HPV 18 cervical cancer patients, those with infections of multiple types, and those with HPV DNA in histologically negative lymph nodes may be at increased risk for recurrence.

Southern blot hybridization and PCR in detection of oral human papillomavirus (HPV) infections in women with genital HPV infections

The presence of human papillomavirus (HPV) in biopsies taken from clinically normal buccal mucosa (n = 212) and clinical lesions (n = 60) was examined by Southern blot hybridization (SBH) using 32P-labelled HPV DNA probes. Furthermore, one hundred formalin-fixed, paraffin-embedded biopsies were analyzed by using polymerase chain reaction (PCR), combined with dot blot hybridization and biotinylated HPV DNA probes. With SBH and PCR, 15.4% and 29.4% of the biopsies, respectively, contained HPV DNA. In clinically normal epithelium, 15.6% and 23.1% of the samples were HPV-positive with SBH and PCR, respectively. The HPV types detected in the genital and oral mucosa of index patients differed in all except two cases. Histology could not be relied on distinguishing HPV DNA positive and HPV DNA negative samples. Hand warts were encountered significantly more frequently in patients with a concomitant oral HPV infection. To conclude, oral HPV infections as detected by SBH and PCR are surprisingly common, but similar to the genital tract, the virus seems to exist in a latent form in the vast majority of cases. The frequent concomitant finding of skin warts and oral HPV infection may suggest some kind of HPV-specific immunosuppression.

High frequency of human papillomavirus infection in carcinoma of the urinary bladder

BACKGROUND AND METHODS

The prevalence of type 6, 11, 16, 18, and 33 human papillomavirus (HPV) was investigated with the polymerase chain reaction (PCR) on formalin-fixed, paraffin wax-embedded material, including 48 neoplastic and 21 normal urinary bladder specimens. The PCR-amplified DNA were analyzed by gel electrophoresis and dot blot and Southern blot hybridization. Some tissues were tested further by nonisotopic in situ hybridization.

RESULTS

HPV DNA was detected in 39 (81%) of 48 carcinomas and 7 (33%) of 21 normal urinary bladder specimens. The presence of high-risk HPV (types 16, 18, and 33) was increased significantly in carcinoma cases (62%) as compared with normal specimens (14%) (P less than 0.01). Similarly, multiple HPV infections were significantly higher in carcinoma (60%) than in the normal tissues (5%) (P less than 0.01). The overall and high-risk HPV infections in both neoplastic and normal specimens were distributed almost equally in male and female patients. There was no significant correlation between positive results for HPV and histologic grades of the carcinoma.

CONCLUSIONS

These results demonstrate that the urinary bladder in both sexes is another site where infection with the common genital tract HPV may carry a risk of malignant transformation.

Human papillomaviruses in normal oral mucosa: a comparison of methods for sample collection

The prevalence of six genital genotypes of HPV was assessed in the clinically normal oral mucosa of an adult Caucasian population, and three methods of sample collection compared. HPV DNA was detected in the mouth of 60% of 60 subjects. HPV 16 was the most prevalent genotype, and positive samples were found most frequently in men over 50. A 3% sucrose mouthwash produced more positive results (51%) than mucosal scrapes of three separate sites (45%) or buccal mucosal biopsies (12%). There was no association of a positive result for HPV DNA with any particular mucosal site. A mouthwash was the preferred single screening method for epidemiologic studies of HPV DNA in the mouth, but the greatest yield of positive samples was obtained if multiple sampling techniques were employed.

Comparison of cervical cytology and the polymerase chain reaction for HPV 16 to identify women with cervical disease in a general practice population

A comparison of the ability of cervical cytology and the polymerase chain reaction (PCR) for human papilloma virus type 16 (HPV 16) to identify women with cervical disease has been performed in a general practice population of 249 women, none of whom were believed to have current cervical disease prior to examination. Within this population, 29 women were found by colposcopy and subsequent histopathology to have evidence of cervical disease [5 with cervical intraepithelial neoplasia (CIN) 3; 8 with CIN 2; and 16 with CIN 1]. The prevalence of HPV 16 in this population was 18.9% (CIN 3, 80%; CIN 2, 50%, CIN 1, 12.5%, normal, 16.8%). Women with severe disease (CIN 2 and CIN 3) had a significantly higher incidence of HPV 16 DNA than those with mild cervical disease (CIN 1) or no cervical abnormality (P = 0.001). There was no significant difference in the ability of either PCR for HPV 16 or cytology to identify women with cervical disease. The combination of screening by cytology and the presence of HPV 16 DNA resulted in the identification of a higher proportion of the women with disease, but this observation did not reach statistical significance. Although the failure to detect disease by the two screening methods was similar, HPV 16 DNA positivity was associated with a higher false-positive rate for disease detection than cytology (P less than 0.03). The PCR assay for detecting HPV 16 in this investigation was shown to have a false-positive rate of 2.4% and a false-negative rate of 10.4%. The prospect of screening women for cervical disease using PCR for HPV 16 is discussed.

Cervical cancer--what role for human papillomavirus?

OBJECTIVE

To review the role of human papillomavirus (HPV) as a causative agent of cancer of the cervix. DATA SOURCES, data synthesis, study selection: Medical journals, recently published text books related to cancer of the cervix and HPV and Papillomavirus Reports were examined to review the pathology of cervical cancer and its precursor lesions, its epidemiology in Australia and overseas, methods of detection of HPV (in particular molecular biology techniques used to diagnose HPV) and evidence linking HPV with genital neoplasia.

CONCLUSION

While there is compelling evidence strongly linking certain HPV types with genital cancer, a causative role is yet to be proven and the aetiology is most likely multifactorial. Detection and typing of high risk genotypes of HPV in the genital tract as a diagnostic exercise to identify those women most at risk of developing genital neoplasia is not currently recommended.

PCR-detected genital papillomavirus infection: prevalence and association with risk factors for cervical cancer

In an investigation conducted in student health clinic patients, the polymerase chain reaction was used to detect human papillomavirus (HPV) DNA, thereby allowing measurement of the prevalence of HPV infection and study of the association between HPV infection and risk factors for cervical cancer. Of 159 women eligible to participate, 105 (66%) provided a specimen of cervical cells for HPV typing, and also answered an interviewer-administered questionnaire which sought information on risk factors for cervical cancer. Nucleic acid extracted from cervical cells was screened with primers for HPV types 6, 11, 16, 18, 33 and with an HPV Consensus primer. Overall, the prevalence of HPV infection was 18.1%, while for HPV-6/11 it was 2.9% and for HPV-16/18 it was 10.5%. There were statistically significant increases in risk of HPV infection with a history of ever having smoked cigarettes (overall, and for HPV-16 alone) and with a history of usually having sexual intercourse during menstrual periods (overall, but not for HPV-16), and these associations were independent of the effects of age at first sexual intercourse and number of sexual partners. The latter 2 variables, as well as the total number of occasions of sexual intercourse, a history of anal intercourse, and a history of ever having used oral contraceptives, were not associated with statistically significant alterations in risk of HPV infection.

Detection of human papillomavirus types 6, 11, 16 and 18 in mucosal and cutaneous lesions by the multiplex polymerase chain reaction

A multiplex polymerase chain reaction (PCR) based on the simultaneous amplification of human papillomavirus (HPV) types 6/11, 16 and 18 in a single-step procedure was developed, using primers chosen in the E6-E7 region. The specificity and sensitivity of this technique have been proved by amplifying mixtures or various amounts of plasmid-containing HPV DNA; it allowed the detection of as few as 5-25 HPV DNA copies. Application of the multiplex PCR to 71 clinical samples showed that HPV DNA was detected in 80% (45/57 cases) of mucosal biopsies and 35% (5/14 cases) of cutaneous specimens. HPV 16 was predominant in high-grade CIN whereas HPV 6 and 11 were detected more frequently in genital condylomas and laryngeal papillomas. In cutaneous Bowen's disease HPV 16, 18 or 6/11 + 16 were detected and in squamous cell carcinomas HPV 6/11 or 16 were found. After sequence amplification with primers of one HPV type, the clinical samples displayed the same HPV types but the frequency of positive and coinfected lesions increased. Thus, multiplex PCR is a valuable technique for typing HPV DNA but coinfections may be underestimated.

In situ evidence for HPV 16, 18, 33 integration in cervical squamous cell cancer in Britain and South Africa

In a previous study three types of HPV signal were described in CIN. It was suggested that a type 1 signal represented episomal HPV while a type 2 signal represented integrated HPV; and a type 3 signal was indicative of both episomal and integrated HPV. To test this hypothesis 91 squamous cell cancers (SCC) of the cervix from Britain and South Africa were examined for HPV 6, 11, 16, 18, 31, 33, 35. Of the South African group (n = 69) 64% contained HPV types 16 (n = 29) and 18 (n = 15). The SCC in the British group (n = 22) contained HPV 16 and HPV 33 in 12 and three cases, respectively. Of the HPV positive biopsy specimens, 86% showed a type 2 signal in keratinising and non-keratinising tumours and the remainder a type 3 signal. Type 3 signal was present only in keratinising tumours. The presence of punctate signal in 100% of HPV containing SCC, together with localisation of HPV signal to sister chromatids in tumour cell mitotic figures in vivo, provides further evidence for type 2, and the punctate component of type 3 signal representing viral integration.

Polymerase chain reaction for detection of human cytomegalovirus infection in a blood donor population

We have used the polymerase chain reaction (PCR) to analyse 420 normal donor blood samples taken at a city centre donation site. Three sets of human cytomegalovirus (HCMV) primers specific to the HXLF6, immediate early and late antigen gp64 genes, of the alpha, beta and gamma antigen coding regions respectively, were used to allow for the possibility of sequence variation. There was perfect correlation between the three sets of primers. Latex agglutination and enzyme-linked immunosorbent assay (ELISA) were also employed to provide data for a comparative study. The complete data show that infection with human cytomegalovirus is not only age related but is also sex related. The female population examined using PCR reached a peak infection rate of 80% by the age of 40-50 years whereas the male population reached a 98% infection rate following an almost linear increase with age. Latex agglutination data shows a similar picture although the infection rate peaks around 20% lower than with PCR. The data shows an increase in sensitivity using the PCR rather than the serology although the clinical significance of this has yet to be determined. The work presented here also demonstrates the suitability of the polymerase chain reaction as a potential diagnostic and epidemiological tool.

Inhibitory effects of urine on the polymerase chain reaction for cytomegalovirus DNA

The inhibitory effects of urine samples taken from neonates and older children, some of which were known to be infected with cytomegalovirus, on the polymerase chain reaction (PCR) were investigated. Urea was the major inhibitory component of urine and inhibited the PCR at a concentration of more than 50 mM. Urine samples from older children were more inhibitory than those from neonates. This correlated with the higher concentration of urea generally found in urine samples from older children compared with neonatal urines. Two of 13 neonatal urine samples, however, were inhibitory despite low urea concentrations--presumably due to metabolites derived from parenteral nutrition. The inhibitory effects of urine were effectively removed by simple dialysis or ultrafiltration. The sensitivity and specificity of PCR for detecting cytomegalovirus DNA in urine were further improved by using "nested" primers and a modified PCR protocol entailing the use of reduced reactants in the first 20 cycles of a two-stage 50 cycle PCR.

Prognostic significance of human papillomavirus (HPV) type and nuclear DNA content in invasive cervical cancer

Eighty-one women treated for an invasive squamous cell carcinoma of the uterine cervix during the period from 1964 to 1987 were studied to assess the prognostic value of human papillomavirus (HPV) types 6,11, 16 and 18, as well as the nuclear DNA ploidy pattern, analyzed using HPV amplification by polymerase chain reaction (PCR) and flow cytometry, respectively. The mean age of the women was 57.7 ± 13.4 years, and the mean follow-up until the patients death or January 1990 was 99 ± 87 months. Altogether, 46 women died; 38 (82.6%) of these deaths were due to cervical cancer. The 5-year survival was significantly correlated with age (P= 0.01), and the FIGO stage of the tumors (P= 0.015), but not with tumor differentiation. Diploid tumor was found in 40 (63.5%) cases, and aneuploid in 23 (36.5%) cases. A DNA index 3= 1.5 was found in 47.8% (11/23) of the cases of aneuploid tumors. The 5-year survival rate in diploid tumors was 60.0% (21/35), as compared to 54.5% (12/22) in aneuploid ones, and in patients with a DNA index of < 1.5, the 5-year survival rate was 58.7% (27/46), as compared to 54.5% (6/11) in those with a DNA index ≥ 1.5. Amplified HPV DNA was found in 30 cases (37.0%) with the pairs of HPV DNA primers for HPV types of 6, 11, 16 and 18. When repeated with the anticontamination primers, only 19 (23.5%) cases remained HPV DNA positive. HPV 16 was the most frequent type present in 57.9% (11/19) of the cases, followed by HPV 18 in 36.8% (7/19). Neither the HPV DNA-positivity nor HPV type proved to be of prognostic significance. The results suggest that despite an intimate association of HPV 16 and 18 in cervical carcinogenesis, the presence of their DNA in cancer biopsies does not seem to have any prognostic value. The most significant prognostic factors are still the age and the FIGO stage at diagnosis. Aneuploid tumors or those with DNA index ≥ 1.5 seem to have a slightly (not statistically significantly) impaired prognosis as compared with the diploid tumors and those with DNA index < 1.5.

Simplified procedures for applying the polymerase chain reaction to routinely fixed paraffin wax sections

The polymerase chain reaction was applied to the analysis of DNA contained in archival paraffin wax embedded material. DNA suitable for the reaction was obtained from these tissues by simple extraction methods, without previous dewaxing of tissue sections. When compared with unfixed material, the reaction efficiency was compromised, so that an increased number of amplification cycles were required to produce equivalent amounts of amplified product. This in turn led to an increase in amplification artefacts, which can be minimised by a simple modification of the standard reaction. Amplification of relatively large DNA fragments was not always successful, and it seems prudent to bear this in mind when designing oligonucleotide primers which are to be used for the amplification of archival material. The efficiency of the procedure can be improved by dividing the amplification cycles into two parts: this reduces the amount of reagent needed, is relatively simple and inexpensive, and can be performed in one working day.

Current problems in the pathology of intra-epithelial lesions of the uterine cervix

Problems in the interpretation and diagnosis of intraepithelial lesions of the uterine cervix include interobserver differences in respect of grading, uncertainty as to the significance of human papillomavirus infection and debate about the current terminology. The role of human papillomaviruses in cervical intra-epithelial neoplasia (CIN) remains unclear and the specific type of virus present does not correlate closely with the behaviour of these lesions. There are defects in the current terminology and in proposed new terminology for CIN; it is suggested that the term 'borderline CIN' should be introduced in cases where there is uncertainty as to whether or not CIN 1 is superimposed on a flat condyloma.