Bovine papillomavirus type 1 monoclonal antibodies.

Bovine papillomavirus type 1 (BPV-1) and type 2 (BPV-2) are the etiologic agents of fibropapillomas in cattle. Polyclonal antisera produced against BPV-1 structural antigens are cross-reactive with BPV-2. In this study BPV-1 type-specific monoclonal antibodies were produced that were not reactive with BPV-2. These monoclonal antibodies could be used for identification of BPV-1 structural antigens in acetone-fixed, frozen sections by immunofluorescence and Formalin-fixed, paraffin-embedded sections by immunoperoxidase techniques. In addition, these antibodies could be used for identification and purification of BPV-1 virions by immune electron microscopy and immunoadsorption techniques, respectively.

Preferential association of human papillomavirus with high-grade histologic variants of penile-invasive squamous cell carcinoma.

BACKGROUND: Human papillomavirus (HPV) is causally associated with cervical squamous cell carcinoma (SCC) and its precursor lesions. By analogy, HPV is believed to play a role in penile cancer through progression of HPV-associated penile squamous intraepithelial lesions (SIL). HPV DNA has been reported to be present in 100% of high-grade penile SIL, but the percentage of invasive or infiltrating penile SCC that was positive for HPV DNA has varied from study to study (positivity values ranging from 32% to 82%). PURPOSE: To ascertain whether HPV is associated with penile cancer, we used a polymerase chain reaction (PCR)-based assay to test specimens of penile SCC for the presence of HPV DNA. METHODS: A total of 117 formalin-fixed, paraffin-embedded specimens of penile cancer from an equal number of patients who had been diagnosed either at the Memorial Sloan-Kettering Cancer Research Center in New York City between 1964 and 1992 or the Universidad Nacional de Asunción in Paraguay between 1980 and 1992 were analyzed. Specimens were examined without prior knowledge of the histology of the lesions. Methods were used that minimized sample contamination, thus avoiding false-positive results. PCR and Southern blot analyses were used to determine HPV type. The presence of HPV DNA was studied for association with the tumor properties histopathology, growth pattern, tumor grade, regional lymph node status, and anatomic location. Two-sided statistical tests were used to determine P values. RESULTS: HPV DNA was detected in 26 (22.2%) of 117 specimens. In 23 (88.5%) of the 26 HPV-positive specimens, HPV type 16 (only) was identified. HPV DNA was frequently associated with SCC in areas showing basaloid and/or warty changes (nine [47.4%] of 19 specimens were HPV positive; P = .0125). More highly significant was the association of virus with basaloid SCC (nine [75%] of 12 specimens were HPV positive; P = .0005). However, HPV was not found to be associated with typical SCC of the penis (five [11.1%] of 45 specimens were HPV positive). Virus DNA was more often associated with high-grade tumors (P = .0278) exhibiting aggressive growth (P = .0382) localized to the glans penis (P = .0324). Stepwise logistic regression analysis revealed that only tumor histopathology was a significant predictor of an HPV association. CONCLUSIONS: The presence of HPV DNA was found to be significantly associated only with those penile SCC exhibiting basaloid changes. Furthermore, HPV DNA sequences tended to be associated with higher grade and more aggressive tumor localized to the glans penis. The low frequency of HPV in penile SCC implies that only a small proportion of these cancers arise from HPV-associated penile SIL.

Oncogenic association of specific human papillomavirus types with cervical neoplasia.

Molecular hybridization analysis of human papillomavirus (HPV) DNA from 190 cervical biopsy specimens from women in the United States, Brazil, and Peru revealed viral sequences in 2 (9%) of 23 biopsy specimens of normal mature squamous epithelium, 7 (44%) of 16 biopsy specimens of metaplastic squamous epithelia, 60 (77%) of 78 cervical intraepithelial neoplasia (CIN), 57 (89%) of 64 invasive squamous carcinomas, and 8 (89%) of 9 endocervical adenocarcinomas. HPV typing by DNA hybridization revealed HPV 6 and HPV 11 sequences in metaplastic squamous epithelia, CIN I, and CIN II, but not in CIN III lesions or invasive carcinomas. HPV 16 was detected in metaplastic epithelium and in nearly half of the invasive squamous carcinomas and adenocarcinomas. It was present in 31% of CIN lesions, increasing in frequency with the severity of CIN from 20% of CIN I to 50% of CIN III. HPV 16 showed a striking difference in geographic distribution, being detected in 36% of the carcinomas from the United States compared to 64% of the carcinomas from Brazil and Peru. HPV 18 was found in metaplastic epithelia and in 17% of carcinomas but in only 1% of CIN lesions. HPV 31 was not found in metaplastic epithelium but was present in 6% of carcinomas and in 18% of CIN lesions. In addition, a group of uncharacterized HPVs, not corresponding to any of the probes used, was found in 5% of normal and metaplastic epithelia and in 18% of CIN and 19% of invasive cancers. These results suggest that individual HPV types that infect the cervix have varying degrees of oncogenic association. HPV 6 and HPV 11 appear to have very little oncogenic association, HPV 31 has low oncogenic association, and HPV 16 and HPV 18 have high oncogenic association.

Immunologic relatedness of papillomaviruses from different species.

An antiserum prepared by immunization of a rabbit with sodium dodecyl sulfate-disrupted virions from a pool of plantar warts was cross-reactive with virus-positive papillomas of other animal species by both indirect immunofluorescence tests on frozen sections of wart tissues and peroxidase-antiperoxidase tests of sections of Formalin-fixed tissues. The antiserum stained plantar warts, common warts, and skin lesions of epidermodysplasia verruciformis, all from humans; bovine fibropapilloma, experimentally produced with bovine types 1 and 2; and transmissible canine oral papillomas. The staining was localized to nuclei of the upper granular layers of the peithelium and was similar in distribution to the pattern produced by antiserum specifically prepared against that papillomavirus. The antiserum did not stain virus-negative warts, or cells infected with simlan virus 40, human polyomavirus BK, and murine polyomavirus. These data suggested that papillomaviruses share a common internal antigen unrelated to a similar antigen described previously for the polyomaviruses (which include simian virus 40 and polyomavirus subgroups).

Characterization of normal human exocervical epithelial cells immortalized in vitro by papillomavirus types 16 and 18 DNA.

An in vitro system for studying the interaction between human papillomavirus (HPV) 16 and 18 recombinant DNA and normal human exocervical epithelial cells is described. Eight HPV-immortalized human exocervical epithelial cell lines were established; all the lines contained either integrated HPV16 or 18 sequences and expressed HPV mRNAs. Thus, integration and expression appear to be required for immortalization. Immortalized cells (greater than 200 population doublings to date) divided rapidly (doubling time of 30 to 46 h) and morphologically resembled primary cultures of normal human exocervical epithelial cells. They expressed a keratin pattern consistent with their origin from exocervical epithelium. When cultured at high density or in the presence of serum they terminally differentiated. Sublines resistant to terminal differentiation were selected by growth in serum-supplemented medium. Keratin pattern changes suggest they have some properties in common with cervical squamous carcinoma cells. However, HPV-immortalized cell lines were not tumorgenic in nude mice. Thus, HPV16/18 is not carcinogenic by itself. These cell lines represent an appropriate model for studying factors that regulate HPV gene expression in normal cervical epithelial cells and examining the influence of cocarcinogens on neoplastic progression.

Biochemical epidemiology of cervical neoplasia: measuring cigarette smoke constituents in the cervix.

In preparation for an epidemiological investigation of cigarette smoking and cervical neoplasia, we studied methods of measuring cervical exposure to tobacco smoke. The measurement of cotinine in cervical flushes by radioimmunoassay proved to be highly accurate in distinguishing smokers from nonsmokers, achieving 100% sensitivity and 97% specificity. In most subjects, quantitative levels of cervical cotinine and nicotine mirrored recent smoking intensity. Some of the apparent exceptions may have resulted from metabolic/secretory traits of the subjects. If so, the biochemical measurement of smoke constituents in the cervix might prove more valuable for epidemiological studies of cervical neoplasia than data on current smoking behavior collected by interview.

Spontaneous malignant transformation of human ovarian surface epithelial cells in vitro.

PURPOSE: Epithelial ovarian cancer has no reliable marker for early detection and no known specific premalignant changes. Human ovarian surface epithelial (HOSE) cells expressing human papillomavirus type 16 (HPV-16) E6/E7 genes undergo crisis, and surviving cells exhibit an immortalized phenotype. Cells show an increasingly invasive phenotype on collagen rafts over time. To ascertain the nature of this aberrant growth, we characterized this spontaneous progression of HOSE cells from a benign to an invasive phenotype using histopathology, immunophenotyping, and tumorigenesis assays. EXPERIMENTAL DESIGN: At various passages, cells were monitored for growth on collagen, response to tumor necrosis factor alpha and daunorubicin, immunohistochemistry and Western blot analysis of E-cadherin and beta-catenin, growth in soft agar, and tumor formation in immunodeficient mice. RESULTS: As passage number increased, cells became increasingly aggressive on collagen, with more pronounced focal stratification and invasion. Furthermore, late-passage cells were more resistant to the apoptotic effects of TNF-alpha and daunorubicin than earlier-passage cells. E-cadherin expression was limited to early-passage cells, whereas beta-catenin was expressed regardless of passage. Cells invading collagen formed colonies in soft agar at low efficiency but were not tumorigenic in immunodeficient mice. Some cultures recovered from colonies grew in soft agar at high efficiencies, and one was tumorigenic. CONCLUSIONS: HOSE cells expressing E6/E7, over time, develop characteristics of malignant cells and produce tumors consistent with an ovarian surface epithelium lineage. Progression of HOSE cells from a benign to an invasive phenotype in vitro may provide a model to dissect the progression of ovarian cancer.

Bradykinin blocks angiotensin II-induced hypertrophy in the presence of endothelial cells.

Angiotensin-converting enzyme inhibitors block left ventricular hypertrophy in vivo. A component of this effect has been attributed to tissue accumulation of bradykinin. Little is known regarding the effect of bradykinin on cardiomyocytes. The objectives of the present study were to define the effects of bradykinin on isolated ventricular cardiomyocytes (from adult and neonatal rat hearts) and to determine the extent to which bradykinin blocks hypertrophy in vitro. Bradykinin was found to be a hypertrophic agonist, as defined by increased protein synthesis and atrial natriuretic peptide secretion and expression. Bradykinin (10 micromol/L) increased [3H]phenylalanine incorporation by 23+/-3% in adult and by 36+/-10% in neonatal cardiomyocytes. Constitutive atrial natriuretic peptide secretion by neonatal myocytes was increased 357+/-103%. All effects of bradykinin were abolished by the B2-kinin receptor antagonist Hoe 140. These increases were similar in magnitude to those observed with phenylephrine (20 micromol/L) and angiotensin II (1 micromol/L). However, in cardiomyocytes cocultured with endothelial cells, bradykinin did not increase protein synthesis. Angiotensin II increased [3H]phenylalanine incorporation by 24+/-3% in adult cardiomyocytes in monoculture and by 22+/-2% in adult rat cardiomyocytes cocultured with endothelial cells. Bradykinin abolished this angiotensin II-induced hypertrophy in myocytes cultured with endothelial cells but not in myocytes studied in the absence of endothelial cells. In conclusion, bradykinin has a direct hypertrophic effect on ventricular myocytes. The presence of endothelial cells is required for the antihypertrophic effects of bradykinin. The results suggest that the increase in local concentration of bradykinin associated with angiotensin-converting enzyme inhibition is an important mechanism by which hypertrophy can be blocked. Manifestation of this mechanism appears to require bradykinin-stimulated release of paracrine factor(s) from endothelial cells, which are also able to block the hypertrophic effects of Ang II.

In vitro-labeled DNA for detecting viral genomes in multiple sclerosis: I. Papovaviruses.

Papovaviruses appear to be neurotropic and one, JC virus, is implicated as the cause of one type of demyelinating disease, progressive multifocal leukoencephalopathy. To investigate whether human papovaviruses play a role in multiple sclerosis, radioactively labeled DNA from BK virus, human papilloma virus, and simian virus 40 was used as a probe in order to detect related unlabeled DNA sequences in DNA isolated from multiple sclerosis brain and/or spinal cord. Labeled viral probes were denatured and DNA allowed to reassociate in the presence of excess unlabeled DNA from multiple sclerosis tissue or from controls. The reassociation rate of the probe is proportional to the concentration of viral DNA present, and an increase in the reassociation rate of the probe over that of control reactions would indicate the presence of unlabeled viral DNA in multiple sclerosis cellular DNA. However, addition of DNA derived from multiple sclerosis patients did not increase rates of reassociation of viral probes. Known human papovaviruses probably have no role in the pathogenesis of multiple sclerosis.

Papillomavirus infection of the cervix. II. Relationship to intraepithelial neoplasia based on the presence of specific viral structural proteins.

Three hundred twenty-two cases of cervical dysplasia (mild, moderate, and severe) and carcinoma in situ (CIS) were examined for the presence of papillomavirus structural antigens with a peroxidase-antiperoxidase method on formalin-fixed, paraffin-embedded tissue. The primary antiserum, prepared from purified, detergent-disrupted bovine papillomavirus type 1 virions, is broadly reactive against the genus-specific (common) antigen(s) of the papillomaviruses. Using the peroxidase-antiperoxidase technique on cervical tissue obtained from biopsy, conization and hysterectomy specimens, papillomavirus structural proteins were identified in association with mild dysplasia in 65 of 152 (43%) cases, with moderate dysplasia in 12 of 82 (15%) cases, with severe dysplasia in eight of 47 (17%) cases, and with CIS in four of 41 (10%) cases. Papillomavirus antigens were found directly within the lesion in all the cases of mild and moderate dysplasia but in only two instances of severe dysplasia and in none of the examples of CIS. In the remaining 10 cases of severe dysplasia and CIS associated with the presence of papillomavirus antigens, cells containing papillomavirus structural proteins were present in areas of moderate dysplasia immediately adjacent to the high-grade lesions in seven instances and in areas of mild or moderate dysplasia not directly in contact with the high-grade lesions in three. Among the 12 high-grade lesions associated with the presence of papillomavirus antigens, a morphologic transition from areas of moderate dysplasia containing papillomavirus antigens to the areas of severe dysplasia and CIS was present in five instances. The results of this study, therefore, provide direct evidence demonstrating the relationship of papillomavirus to intraepithelial cervical neoplasia ranging from mild dysplasia to severe dysplasia and CIS.

Basaloid squamous cell carcinoma: a distinctive human papilloma virus-related penile neoplasm: a report of 20 cases.

Most penile neoplasms are squamous cell carcinomas (SCC), but there are subtypes that show morphologic and possibly etiologic differences. Clinicopathologic features of 20 patients with basaloid carcinoma (BC), an unusual variant of squamous cell carcinoma, are presented. Median age was 52 years, and all tumors were located in the glans, three confined to the perimeatal region. Average tumor size was 3.8 cm. Microscopically, nests of small, basophilic cells with numerous mitosis were present. Human papillomavirus DNA sequences (type 16), using the polymerase chain reaction (PCR), were found in 9 of 11 cases. Differential diagnosis included urethral transitional cell, basal cell, small cell neuroendocrine, and metastatic carcinoma. Factors more significantly associated with regional metastasis and mortality were tumor thickness greater than 10 mm and infiltration of the corpus cavernosum. A comparison with typical squamous cell carcinoma showed basaloid carcinoma to have a higher histologic grade, a deeper invasion of penile anatomic levels, and a higher mortality rate. Of 17 patients observed, 10 were dead of disease (average time, 34 months), one was alive with disease 6 months after diagnosis, and 5 were alive and free of disease (average time, 71 months); the remaining patient died of other causes. Basaloid carcinoma is a distinctive morphologic subtype of squamous cell carcinoma frequently associated with the human papilloma virus.

The role of human papillomaviruses in the pathogenesis and histologic classification of precancerous lesions of the cervix.

It is clear that the relation between HPV infection and cervical neoplasia is more complex than initially realized. Preliminary molecular virologic data suggest preferential distributions of low- and high-risk HPV types in CIN that tend to correlate with the morphologic appearance. Thus, mild and moderate dysplasias (CIN I and II) contain a diverse distribution of HPV types, including a minority that have a high risk of malignant potential. HPV, therefore, appears to play a major role as a promoter. Neoplastic transformation is probably determined by specific HPV types but, in addition, requires initiation by some other carcinogenic stimulus, e.g., HSV II, cigarette smoking. Despite numerous studies, performed during the past 30 years, the long-term behavior of dysplasia remains uncertain. The natural history of HPV-associated lesions is unknown. Until this information is available, it is recommended that the conventional dysplasia--CIS or CIN nomenclature be used. The presence of associated viral changes can be considered and added to the diagnosis, e.g., "moderate dysplasia (CIN II) with evidence of papillomavirus infection." Treatment should be the same for all intraepithelial lesions, regardless of the presence of morphologic evidence of HPV. In the future, it may be necessary to modify the classification of precancerous lesions of the cervix if it is shown that a specific HPV type induces a characteristic morphologic alteration or that the HPV type, in and of itself, has greater prognostic significance. Until then, confusion will be minimized and management optimized if the conventional dysplasia--CIS or CIN nomenclature is employed.

Cervical papillomavirus infection in diethylstilbestrol-exposed progeny.

Histologic sections from cervical and vaginal biopsies showing dysplasia in 37 women exposed to diethylstilbestrol (DES) in utero were stained for human papillomavirus structural antigens using an immunoperoxidase technique. Forty-three percent of the lesions had detectable papillomavirus antigens. These findings indicate that a significant proportion of cervical dysplasia observed in DES-exposed progeny is associated with papillomavirus infection.

Verrucous carcinoma of the vulva associated with an unusual type 6 human papillomavirus.

An unusually rapid growing vulvar verrucous carcinoma found associated with human papillomavirus type 6 is described. Both human papillomavirus structural antigens and deoxyribonucleic acid (DNA) sequences were detected in the tumor biopsy. The human papillomavirus genome was isolated and compared with the genome of human papillomavirus type 6b, which was cloned from an anogenital wart. The two genomes were extremely homologous in genomic organization and DNA sequence, except for a region on the viral genome containing the virus control elements. A discussion of this observation and how it could relate to the importance of viral subtypes follows.

Correlation of cellular atypia and human papillomavirus deoxyribonucleic acid sequences in exfoliated cells of the uterine cervix.

Restriction enzyme digestion and Southern blot hybridization were used to analyze deoxyribonucleic acid (DNA) extracted from exfoliated cervical cells for the presence of human papillomavirus sequences and these results were correlated with cytologic findings on Papanicolaou smears. Specimens (N = 204) were obtained from a nonselected population of women undergoing routine cytologic screening and human papillomavirus DNA sequences were detected in 33 (16%) women. Thirteen smears contained atypical squamous cells, ranging from very mild dysplasia to moderate dysplasia; all showed associated morphologic evidence of human papillomavirus infection characterized by koilocytosis, nuclear enlargement, wrinkling, and hyperchromasia, and human papillomavirus DNA was demonstrable in 12 (92%) smears. Of the remaining 191 samples with normal cytology, 21 (11%) also contained human papillomavirus DNA sequences. Reevaluation of the smears from these women resulted in a revision of the cytologic diagnosis to very mild dysplasia in four cases. These data suggest that human papillomavirus infection occurs more frequently than predicted by cytologic screening.

Nonrandom chromosomal imbalances in human ovarian surface epithelial cells immortalized by HPV16-E6E7 viral oncogenes.

We had previously immortalized human ovarian surface epithelial (HOSE) cells using HPV16E6E7 ORFs. In order to identify crucial genetic events involved during cell immortalization, the genomic profile of immortalization of five HOSE cell lines was analyzed by comparative genomic hybridization. Our results showed that chromosomal imbalance was common in HOSE cells after immortalization. The common chromosomal imbalances identified in immortal HOSE cells are: +19q13.1 (5/5 lines), -13q12 approximately qter (4/5 lines), +5q15 approximately q33 (3/5 lines), +20q11.2 approximately q13.2 (3/5 lines) and -22q11.2 approximately qter (3/5 lines). Other chromosomal imbalances, which were detected in two of the five immortal HOSE cell lines, included gains on chromosome 1 and 11q12 approximately q13, and losses on 2p, 4q, 8p, 10p and 11q14 approximately qter. The chromosomal imbalances observed in HOSE cells before immortalization include -8pter approximately p11.2, -11q23 approximately qter, -13q12 approximately qter and +19 which may represent early genetic events during cell immortalization. The genomic profile was examined in one HOSE cell line (HOSE 6-3) at various stages of immortalization. The genomic profiles of HOSE 6-3 cells after crisis were largely stable. A few additional chromosomal imbalances were detected in the immortalized HOSE cells after an extensive culture period including +11pter approximately q23, -15q23 approximately qter, and +17q12 approximately qter. Identification of nonrandom chromosomal imbalance in immortalized HOSE cells may facilitate the identification of specific chromosomes harboring genes involved in the immortalization of human ovarian surface epithelial cells.

Clinical models of chemoprevention for cervical cancer.

Cervical carcinoma creates a worldwide, significant population burden that potentially could be reduced by new preventive strategies for cervical cancer such as chemoprevention. Given the vast array of clinical and molecular information available relating to cervical cancer and the precursor lesions along with a growing number of new molecular techniques, a model is needed to guide further investigation. Such a model would facilitate research design, guide hypothesis development and testing, and focus the use of molecular data collection and analysis. This article reviews the clinical and molecular data of cervical cancer and the precursor lesions in order to develop a model for chemoprevention research in cervical cancer.

Interferon-alpha therapy of recurrent conjunctival papillomas.

Five patients with multiple, recurrent conjunctival papillomas underwent surgical excision of their tumor and then received interferon alpha-N1, 5 X 10(6) units/m2 (5 Mu/m2), intramuscularly daily for one month. A similar dose was given two to three times per week for the next six months and tapered off or discontinued thereafter. The follow-up period varied from one to four years. Two patients have had no recurrence of tumor. The other three patients have had recurrences of lesser severity upon tapering or discontinuing the interferon, and repeat surgical or laser excision of these lesions has been performed. The presence of koilocytosis and human papillomavirus type 11a DNA sequences was noted in all specimens large enough to examine, whereas papillomavirus structural antigens were detected in only two of five specimens. A regimen of interferon therapy appears to be tumor suppressive, but not curative.

Detection of human papillomavirus DNA sequences in conjunctival papilloma.

Two histologically proven conjunctival papillomas (one from a 33-month-old boy and the other from a 28-year-old woman) were examined for the presence of papillomavirus by DNA molecular hybridization. The first case, a recurrent tumor known to be positive for papillomavirus structural antigen, demonstrated human papillomavirus DNA sequences that cross-hybridized to a human papillomavirus type 11 DNA probe. The second case, an initial tumor, which was negative for papillomavirus structural antigen, demonstrated no viral DNA sequences by hybridization.

Detection of papillomavirus common antigens in lesions of skin and mucosa.

HPV infections are associated with many proliferative lesions of cutaneous and mucosal squamous epithelium. PV genus-specific (common) antigens can be detected by immunocytochemical techniques in approximately 50% of lesions (warts and papillomas) without dysplastic changes. Dysplastic lesions of squamous epithelium are less likely to be permissive for viral expression; squamous neoplasias are rarely, if ever, productively infected. Almost any tissue that has been processed for pathology or exfoliative cytologic preparations can be reliably stained for the presence of papillomavirus common antigens. A positive staining reaction is interpreted as meaning that the lesion is associated with HPV infection and that it has a potential for being contagious.