Vulvar vestibulitis is rarely associated with human papillomavirus infection types 6, 11, 16, or 18

Vulvar vestibular biopsy specimens from 31 women with clinical and pathologic findings of vulvar vestibulitis were studied using polymerase chain reaction (PCR) for the identification of human papilloma virus (HPV). The PCR technique specifically probed for HPV types 6, 11, 16, and 18. Of the 31 subjects, three were found to have HPV within the biopsy specimens; two had HPV type 11 and one had HPV 16. Five of the 31 cases had histopathologic features of koilocytosis consistent with HPV effect; three of these five were found to have HPV. The findings support the hypothesis that HPV types 6, 11, 16, and 18 are rarely associated with vulvar vestibulitis. The frequencies identified were similar to those seen with control patients. True koilocytosis is the most useful pathologic feature distinguishing HPV-related cases; it is rarely identified in typical vulvar vestibulitis. Nonspecific changes in the vestibular epithelium associated with glycogen effect should not be interpreted as koilocytosis.     

Prevalence of human papillomavirus types 16 and 18 in penile carcinoma: a study of 41 cases using PCR

AIMS: To determine retrospectively the prevalence of human papillomavirus (HPV) types 16 and 18 in penile carcinomas. METHODS: Forty one surgically resected penile carcinomas from the archives at Queen Mary Hospital, Hong Kong, were reviewed and classified into verrucous carcinoma, and well, moderately, and poorly differentiated squamous cell carcinomas. Paraffin wax embedded tumour tissue was sectioned and analysed for HPV 16 and HPV 18 using the polymerase chain reaction with type specific internal probes. RESULTS: There were seven verrucous carcinomas, and 11 well, 17 moderately, and six poorly differentiated squamous cell carcinomas. Six of the 41 (15%) patients had penile carcinoma containing HPV 16 or HPV 18 DNA, or both, with HPV 16 found in four (10%) and HPV 18 in four (10%). The mean ages of HPV positive and HPV negative groups of patients were 68.5 and 57.6 years, respectively (p < 0.05). None of the seven verrucous and 11 well differentiated squamous cell carcinomas was positive for HPV. The mean age of patients who had these carcinomas was 52.4 years. As a group, these low grade carcinomas occurred in patients younger by more than a decade than those who had carcinomas of the higher grades (mean age 64.4 years; p < 0.01). CONCLUSIONS: Penile carcinomas had much lower rates of infection by HPV 16 or HPV 18 than cervical carcinomas in this Hong Kong population. Based on our findings and on data collated from published findings, it is concluded that penile verrucous carcinomas are not associated with HPV 16 and HPV 18. The overall low prevalence of HPV 16 and HPV 18 in penile carcinomas suggests that other HPV types might be important in the pathogenesis of these tumours.     

Seroprevalence of human papillomavirus types 6 and 16 capsid antibodies in homosexual men

Human papillomavirus (HPV) has been implicated in the pathogenesis of anal carcinoma, which is increased in homosexual men. Little is known about the serologic response to HPV in normal or immunosuppressed men; therefore, HIV-infected and -uninfected homosexual men were screened for HPV-6 and -16 capsid antibodies. HIV-infected men had increased HPV DNA detection but did not significantly differ in the prevalence of serum HPV antibodies. HPV-6 DNA detection and the presence of anal warts were significantly correlated with serum antibody overall and in the HIV-infected subgroup. HPV-16 DNA detection was not significantly correlated with serum antibody overall or in either subgroup; however, HIV-infected men with high-grade anal squamous intraepithelial lesions were significantly more likely to have HPV-16 antibodies. HIV-infected men are able to generate an antibody response to HPV, and a lack of serum HPV antibodies cannot explain the increased HPV-associated disease seen in HIV-infected men.     

Elevated p16 at senescence and loss of p16 at immortalization in human papillomavirus 16 E6, but not E7, transformed human uroepithelial cells

CDKN2/p16 inhibits the cyclin D/cyclin-dependent kinase complexes that phosphorylate pRb, thus blocking cell cycle progression. We previously reported that p16 levels are low to undetectable in normal human uroepithelial cells (HUCs) and in immortalized uroepithelial cells with functional pRb, whereas p16 levels are markedly elevated in immortal HUCs with altered pRb (T. Yeager et al., Cancer Res., 55: 493-497, 1995). We now report that elevation of p16 levels occurs at senescence in HUCs, including HUCs transformed by human papillomavirus 16 E7 or E6, whose oncoprotein products lead to functional loss of pRb and p53, respectively. We also report that six of six independently immortalized E7 HUCs show high levels of p16 similar to those observed at HUC senescence, whereas p16 is undetectable in five of five immortal E6 HUCs. Four of the five independent E6 HUCs that lost p16 at immortalization showed hemizygous deletion of the 9p21 region. However, no homozygous CDKN2 deletions were detected, and only one CDKN2 mutation was identified. For the first time, these data associate elevated p16 with senescence in human epithelial cells. These data also suggest that a component of immortalization may be abrogation, either by pRb inactivation (as in the E7-transformed HUCs) or by p16 inactivation (as in the E6-transformed HUCs), of a p16-mediated senescence cell cycle block.     

Characterization of a human papillomavirus type 16 variant-dependent neutralizing epitope

We have determined that three type-specific and conformationally dependent monoclonal antibodies, H16.E70, H16.U4, and H16.V5, neutralize pseudotype human papillomavirus type 16 (HPV16) virions in vitro. H16.U4 and H16.V5 neutralized pseudotype virions derived from the German HPV16 variant 114K and the Zairian variant Z-1194 with equal efficiency. In contrast, neutralization of Z-1194 pseudotype virions by H16.E70 was two orders of magnitude weaker than neutralization of 114K pseudotype virions. This difference correlated with enzyme-linked immunosorbent assay reactivity of H16.E70 to L1 virus-like particles of the two variants. A substitution at residue 282 of L1 was responsible for this differential reactivity, suggesting that this residue constitutes part of the H16.E70 epitope.     

Association of the antibodies against human papillomavirus 16 E4 and E7 proteins with cervical cancer positive for human papillomavirus DNA

Occurrence of the antibodies against human papillomavirus (HPV) 16 proteins E4 and E7 is specifically but independently associated with cervical cancer. To correlate HPV DNA and antibody data, we examined the biopsy specimens and sera, by polymerase chain reaction (PCR) and by ELISA, respectively, from 51 patients with cervical cancer (including 3 recurrent cases) and 22 with cervical intra-epithelial neoplasia. Consensus primers for the L1 region were used for PCR and bacterially expressed, purified fusion protein HPV-16 E4 and non-fusion protein HPV-16 E7 were used for ELISA. HPV-16 DNA and other HPV types were detected in 17 and 25, respectively, out of 51 cases of cervical cancer. Ten out of the 17 HPV-16-DNA-positives were positive either for anti-E4 or for anti-E7: positivities for anti-E4, for anti-E7, and for both were 6/17, 5/17 and 1/17 respectively. Three anti-E7-positives consisted of those for HPV-33, -52 and -58 DNA, suggesting that limited cross-reaction occurred between the HPV types. Among the HPV-16-DNA-positive cases of cancer, lymph-node or distant metastasis was recorded more frequently in the seropositives than in the seronegatives. Our results show that the HPV-16 anti-E4 or anti-E7 occurs in some, but not in all, of the HPV-16-DNA-positive cases, and support the hypothesis that the presence of the HPV-16 antibodies can be used as a marker for possible metastasis.     

Prevalence of human papillomavirus infection and HPV DNA among male partners of Israeli women with genital premalignant and human papillomavirus lesions

The role of the males who are sexual partners of females with genital human papillomavirus (HPV) infection and premalignant lesions is explored in the present study. Within a period of 3 years, 391 females with genital premalignant and HPV-associated lesions were examined and treated at the Cervical Pathology Unit of the Tel Aviv Medical Center. The male partners of all the women were asked to attend this unit, and 322 of them responded. All participants underwent colposcopic examination of the anogenital area followed by colposcopically guided biopsies from the most representative lesions, when present, part of which included in situ hybridization (ISH) of HPV DNA sequences 6/11 and 16/18. The histological prevalence of HPV among the male partners was 86.6% (185 of 213 biopsies). Of the 48 couples who had ISH evaluations, the ISH could not identify any copy of HPV DNA in 58.3% of the males (28 cases) and 41.6% of the females (20 cases). Among the males, HPV 6/11 and 16/18 were found in 17 (35.4%) and 3 cases (6.2%), respectively, and among the females there were 23 (48.0%) and 5 cases (10.4%), respectively. Correlation of HPV DNA sequences 6/11 and 16/18 between the couples was found in six (12.5%) and in one (2.0%), respectively. These data do not support a direct contamination by the current male partner. The question of treating the male partner of a woman with genital HPV and premalignant lesions remains to be evaluated.     

Bacterial expression and immunological detection of human papillomavirus type 16 E7 protein

We have expressed an unfused E7 protein from human papillomavirus 16 into Escherichia coli by using a T7-RNA polymerase system. E7 mRNA was detected one hour after promoter induction. Western blot analysis using either a murine monoclonal antibody elicited against E7 or sera from cervical carcinoma patients demonstrated that recombinant E7 expressed in E. coli reacted to both of them, and a 21 kD band is observed as a positive signal. This protein provides a suitable material for further protein structure and immunological studies and offers a screening tool for identification of circulating antibodies in human sera.     

Changes in body image, depression, and anxiety levels among women with human papillomavirus infection

In the present study, we examined the expression of CD44 variant exons in human oral squamous cell carcinoma (OSCC). Of ten cell lines from OSCCs, two (KB and H357), as well as the HeLa cell line, failed to express CD44 variant exons. In surgical specimens, all normal mucosa expressed CD44v9 (both mRNA and protein). Of 40 primary OSCCs, 19 (47.5%) showed downregulation of CD44v9, which correlated with tumor cell differentiation, primary metastasis to lymph nodes and secondary metastasis to lymph nodes. The results suggest that the downregulation of CD44v9 may play a role in lymphatic metastasis of OSCC and changes in its expression may be a useful diagnostic tool to determine the metastatic potential of OSCC to lymph nodes. Moreover, three cell lines that failed to express CD44 variant exons might become a useful experimental model to study the role of variant exons in the progression of OSCC.     

Stability over time of serum antibody levels to human papillomavirus type 16

Protein concentration, leukocyte density, and lactate concentration were studied in 41 pairs of ventricular and lumbar CSF drawn at an interval of less than 24 hours from patients with suspected bacterial CNS infections. The ventriculo-lumbar ratios ranged from 0.003 to 10.2 (median=0.42) for protein and from 0.002 to 53.5 (median=0.17) for leukocytes. The uneven distribution of leukocytes and proteins in the CSF space may produce findings that fail to indicate bacterial CNS infections. Lactate was distributed more homogeneously in the CSF space than protein and leukocytes (ventriculo-lumbar ratio 0.52 to 1.66 [median=0.811).     

Socioeconomic geographical links to human immunodeficiency virus seroprevalence among childbearing women in Montreal, 1989-1993

Anti-idiotype (anti-Id) antibody can induce tumor dormancy in a murine B lymphoma, BCL1, by its ability to induce cell cycle arrest and apoptosis (negative signaling). In human B lymphoma, there is accumulating evidence that the antitumor effect of anti-Id or several other B cell-reactive antibodies relates to their ability to act as agonists rather than conventional effector antibodies. In this study, we sought to elucidate the role of cyclins, cyclin-dependent kinases (CDKs), and their inhibitors in anti-IgM-induced cell cycle arrest to better understand the mechanisms underlying cancer dormancy. To accomplish this, we have performed in vitro studies with a human lymphoma cell line (Daudi) because its response to anti-Id (or anti-IgM) is similar to that of a BCL1 cell line, more reagents are available, and the results would be particularly pertinent to therapy of human B cell lymphomas. Our results show that cross-linking of membrane IgM on Daudi cells induces an arrest late in G1 and prevents pRb from becoming phosphorylated. The G1 arrest is correlated with an induction of the CDK inhibitor p21 and reduced CDK2 activity, although the level of CDK2 protein was not changed. Coprecipitation of CDK2 with p21 in anti-IgM-treated cells and the unchanged level of cyclin E suggest that p21 is responsible for the reduction of CDK2 activity and therefore blockade of the cell cycle. The induction of p21 was not accompanied by changes in p53 levels. As a result of the G1 block, cyclin A levels sharply declined by 24 h after anti-IgM treatment. There was no evidence for involvement of CDK4 or CDK6 in the blockade. These results provide evidence that membrane IgM cross-linking on Daudi cells induces expression of p21 and a subsequent inhibition of the cyclin E-CDK2 kinase complex resulting in a block to pRb phosphorylation and cell cycle arrest late in G1.     

In vitro generation and type-specific neutralization of a human papillomavirus type 16 virion pseudotype

We report a system for generating infectious papillomaviruses in vitro that facilitates the analysis of papillomavirus assembly, infectivity, and serologic relatedness. Cultured hamster BPHE-1 cells harboring autonomously replicating bovine papillomavirus type 1 (BPV1) genomes were infected with recombinant Semliki Forest viruses that express the structural proteins of BPV1. When plated on C127 cells, extracts from cells expressing L1 and L2 together induced numerous transformed foci that could be specifically prevented by BPV neutralizing antibodies, demonstrating that BPV infection was responsible for the focal transformation. Extracts from BPHE-1 cells expressing L1 or L2 separately were not infectious. Although Semliki Forest virus-expressed L1 self-assembled into virus-like particles (VLPs), viral DNA was detected in particles only when L2 was coexpressed with L1, indicating that genome encapsidation requires L2. Expression of human papillomavirus type 16 (HPV16) L1 and L2 together in BPHE-1 cells also yielded infectious virus. These pseudotyped virions were neutralized by antiserum to HPV16 VLPs derived from European (114/K) or African (Z-1194) HPV16 variants but not by antisera to BPV VLPs, to a poorly assembling mutant HPV16 L1 protein, or to VLPs of closely related genital HPV types. Extracts from BPHE-1 cells coexpressing BPV L1 and HPV16 L2 or HPV16 L1 and BPV L2 were not infectious. We conclude that (i) mouse C127 cells express the cell surface receptor for HPV16 and are able to uncoat HPV16 capsids; (ii) if a papillomavirus DNA packaging signal exists, then it is conserved between the BPV and HPV16 genomes; (iii) functional L1-L2 interaction exhibits type specificity; and (iv) protection by HPV virus-like particle vaccines is likely to be type specific.     

Detection of tumor virus infections with HPV 16, 18, and 33 from cytologic material in the uterine neck using the PCR method

A method for detection of oncogenic viruses HPV 16, 18, 33 based on enzymatic amplification (PCR) of specific viral DNA sequences is described. This technique has many advantages, including: specificity, reproducibility, relatively simple procedure and low cost.     

Isolation and propagation of human papillomavirus type 16 in human xenografts implanted in the severe combined immunodeficiency mouse

We report the isolation and propagation of human papillomavirus type 16, the main agent of cervical cancer, using human foreskin fragments implanted in severe combined immunodeficiency mice. The infection produced viral particles, and with each passage of the virus it caused lesions identical to intraepithelial neoplasia, the precursor to carcinoma.     

Genomic variation of human papillomavirus type 16 and risk for high grade cervical intraepithelial neoplasia

BACKGROUND: Epidemiologic studies have demonstrated strong and consistent associations between the detection of human papillomavirus (HPV) type 16 DNA and the risk of cervical intraepithelial neoplasia (CIN) and cervical cancer. However, HPV16 is also the most common type of HPV in the normal population, and only a minority of women with HPV16 infection develop cervical cancer. Studies of genomic heterogeneity in HPV16 have demonstrated the presence of multiple variant forms in all human populations examined to date. It is conceivable that the natural variants of HPV16 in a given population may not have the same biologic behavior. PURPOSE: This study was designed to determine the association between natural variants of HPV16 and the risk of biopsy-confirmed CIN 2 or 3, the most important precancerous lesions of the uterine cervix. METHODS: Prospective studies were conducted among 1) women attending a university and 2) women presenting to a sexually transmitted disease clinic. Subjects were eligible for inclusion in this investigation if the initial cytologic findings did not reveal CIN 2-3 and HPV16 DNA was detected by means of a polymerase chain reaction (PCR)-based method in one or more cervical or vulvovaginal samples. Eligible subjects were followed every 4 months with cervical Pap smears and colposcopic examinations. Women were referred for biopsy if cytology or colposcopy suggested CIN 2-3. Two groups of HPV16 variants, prototype-like and nonprototype-like, were determined by means of single-strand conformation polymorphism (SSCP) analysis of PCR products from the noncoding region of the viral genome. Representative SSCP patterns from HPV16 variants were further characterized by direct DNA sequencing of the PCR products. Relative risks (RRs) and 95% confidence intervals (CIs) were calculated by Cox regression analysis. RESULTS: Prototype-like variants accounted for 79% of the HPV16 detected in university students and 86% of the virus detected in patients presenting to the sexually transmitted disease clinic. CIN 2-3 was confirmed by biopsy in nine of 57 HPV16-positive women attending the university and in 10 of 66 HPV16-positive women presenting to the sexually transmitted disease clinic. Among university students, those with HPV16 nonprototype-like variants were 6.5 (95% CI = 1.6-27.2) times more likely to develop CIN 2-3 than those with prototype-like variants. A similar association was observed among women presenting to the sexually transmitted disease clinic (RR = 4.5; 95% CI = 0.9-23.8). CONCLUSIONS: This study suggests that the risk of developing CIN 2-3 is not the same with all variants of HPV16 and that nonprototype-like variants confer a greater risk compared with prototype-like variants. The important genomic differences underlying this increased risk of CIN 2-3 remain to be determined.