Search for human papillomavirus, herpes simplex virus and c-myc oncogene in human genital tumors

Replication and interaction of herpes simplex virus and human papillomavirus in differentiating host epithelial tissue

We have investigated the interactions and consequences of superinfecting and coreplication of human papillomavirus (HPV) and herpes simplex virus (HSV) in human epithelial organotypic (raft) culture tissues. In HPV-positive tissues, HSV infection and replication induced significant cytopathic effects (CPE), but the tissues were able to recover and maintain a certain degree of tissue integrity and architecture. HPV31b not only maintained the episomal state of its genomic DNA but also maintained its genomic copy number even during times of extensive HSV-induced CPE. E2 transcripts encoded by HPV31b were undetectable even though HPV31b replication was maintained in HSV- infected raft tissues. Expression of HPV31b oncogenes (E6 and E7) was also repressed but to a lesser degree than was E2 expression. The extent of CPE induced by HSV is dependent on the magnitude of HPV replication and gene expression at the time of HSV infection. During active HSV infection, HPV maintains its genomic copy number even though genes required for its replication were repressed. These studies provide new insight into the complex interaction between two common human sexually transmitted viruses in an in vitro system, modeling their natural host tissue in vivo.

Herpes simplex virus type II is not a cofactor to human papillomavirus in cancer of the uterine cervix

OBJECTIVE

Cells that were cotransfected with herpes simplex virus-16 and the herpes simplex virus type 2 Xho -2 DNA induce tumors in nude mice. In a cross-sectional study, we investigated the role of herpes simplex virus type 2 as a cofactor to human papillomavirus in cervical cancer.

STUDY DESIGN

Cervical cells that were obtained with an endocervical Cytobrush brush (Medscand) from 439 women (50 women with cancer lesions, 65 women with high-grade squamous intraepithelial lesions, 80 women with low-grade squamous intraepithelial lesions, 244 healthy subjects) and DNA that was extracted from 150 cervical cancer biopsy specimens were analyzed with polymerase chain reaction for herpes simplex virus type 2 Xho -2 and Bgl IIC transforming DNA sequences.

RESULTS

All 439 cervical samples and 150 cervical cancer biopsy specimens tested negative for herpes simplex virus type 2 Xho -2 and Bgl IIC DNA by polymerase chain reaction. Overall, none of 200 samples (0%) from women with invasive cervical cancer contained herpes simplex virus type 2 Xho -2 or Bgl IIC DNA (95% CI, 0.0-1.8).

CONCLUSION

Although herpes simplex virus type 2 Bgl IIN transforms epithelial cells in vitro, it was not detected in cervical cancer specimens.

Surrogate endpoint biomarkers and their modulation in cervical chemoprevention trials

BACKGROUND

Surrogate endpoint biomarkers (SEBs) are used as intermediate indicators of a reduction in cancer incidence in chemoprevention studies. SEBs should be expressed differentially in normal and high risk tissue; appear at a well defined stage of carcinogenesis; be studied with reasonable sensitivity, specificity, and accuracy; and be modulated in chemoprevention trials. The concept of SEBs may be useful in the trials of many new therapies.

METHODS

The current review includes a comprehensive review of the literature. Many SEBs have been the subject of intense study and include quantitative histopathology and cytology, proliferation markers, regulation markers, differentiation markers, general genomic instability markers, and tissue maintenance markers. Because of the critical biologic and epidemiologic role of the human papillomavirus (HPV) in cervical carcinogenesis, the relation between these markers and HPV should be considered. In addition, biomarkers of HPV infection and its regression should be sought.

RESULTS

Several chemoprevention trials have been published that have included the use of SEBs. The biomarkers that appear most promising in these clinical trials can be measured quantitatively and reproducibly: quantitative histology and cytology, proliferating cell nuclear antigen (PCNA), MIB-1, MPM-2, HPV viral load, epidermal growth factor receptor, polyamines, and ploidy. The markers that have been demonstrated to be modulated in chemoprevention trials in the literature are quantitative histology and cytology, PCNA, MPM-2, HPV viral load, and polyamines.

CONCLUSIONS

The surrogate endpoint biomarkers of most interest in future research should correlate well with HPV infection, be modulated by several therapeutic agents, and have limited variability and ease in measurement.

Distinct cytogenetic alterations in squamous intraepithelial lesions of the cervix revealed by laser-assisted microdissection and comparative genomic hybridization

BACKGROUND

It has been established that comparative genomic hybridization (CGH) on Papanicolaou-stained cervical smears can be used to identify chromosomal imbalances.

METHODS

In this study, the authors identified normal and dysplastic squamous epithelial cells cytologically, eliminated surrounding bacteria or leukocytes by a ultraviolet laser microbeam under microscopic control, and scraped out the cell groups of interest by a microdissection system. In 3 cases of squamous intraepithelial lesions (SIL), a total of 9 samples of dysplastic (n = 6) and nontumorous cells (n = 3) were investigated, each of them consisting of 3-40 cells. The DNA was amplified by degenerate oligonucleotide primed PCR (DOP-PCR) and used for CGH.

RESULTS

Analyses of all nontumorous cell groups resulted in fluorescence ratio profiles that showed no deviation from the normal range, confirming that no methodologic artefacts have been produced. The CGH profiles from dysplastic cells, however, showed various chromosomal imbalances affecting six to nine different chromosomes. The most frequent gains in DNA were observed on chromosomes 1p, 2q, 4, and 5, whereas losses were found on chromosomes 6q and 13q.

CONCLUSIONS

The results of this study demonstrate the feasibility and reliability of CGH on microdissected cell samples of routinely processed cervical smears. To the authors' knowledge, this is the first study reporting the use of CGH on cervical routine smears. This approach offers the opportunity to investigate sequence copy number changes in small, morphologically well-defined groups of dysplastic cells. It may, therefore, serve as a cytogenetic screening test for identifying chromosomal aberrations in precancerous lesions that are associated with a high risk for progression to invasive cancer.

Uterine cervical dysplasia and cancer: identification of c-myc status by quantitative polymerase chain reaction

The c-myc oncogene status was determined in patients with nondysplasia (ND; 9 patients), low-grade squamous intraepithelial lesion (LGSIL; 12 patients), high-grade squamous intraepithelial lesion (HGSIL; 21 patients) and invasive squamous cell carcinoma (ISCC; 20 patients) of uterine cervix using fluorescent quantitative polymerase chain reaction (PCR). In the same paraffin-embedded specimens, other potential risk factors were also screened: human papillomavirus (HPV) infection, Ha-ras codon 12 mutation, DNA aneuploidy. Gene amplification, identified as c-myc copy numbers greater than the mean value +2 SD of patients with ND, was seen in 44% patients with LGSIL, 76% patients with HGSIL, and 67% patients with ISCC. These data indicate that c-myc amplification is one of the critical early events in the progression of uterine cervical lesions. HPV infection of various subtypes was identified in 0% patients with ND, 55% patients with LGSIL, 95% patients with HGSIL, and 84% patients with ISCC. No codon 12 mutation of the Ha-ras gene was found in this series. Aneuploid DNA pattern was seen in 0% patients with ND, 58% patients with LGSIL, 90% patients with HGSIL, and 80% patients with ISCC. There was a significant correlation between HPV infection and DNA aneuploidy. However, no relationship was seen between c-myc status and other factors in this series. Patients with HGSIL and ISCC almost always (95%) had multiple risk factors, whereas more than half of the patients with LGSIL had no or only one risk factor (P = 0.0001).

Chemoprevention trials and surrogate end point biomarkers in the cervix

Cervical cancer is the second most common malignancy in women worldwide and remains a significant health problem for women, especially minority and underserved women. Despite an understanding of the epidemiologic risks, the screening Papanicolaou smear, and morbid and costly treatment, overall survival remains 40%. New strategies, based on the clinical and molecular aspects of cervical carcinogenesis, are desperately needed. Chemoprevention refers to the use of chemical agents to prevent or delay the development of cancer in healthy populations. Chemoprevention studies have several unique features that distinguish them from classic chemotherapeutic trials; these features touch on several disciplines and weave knowledge of the biology of carcinogenesis into the trial design. In the design of chemoprevention trials, four factors are important: high risk cohorts must be identified; suitable medications must be selected; study designs should include Phases I, II, and III; and studies should include the use of surrogate end point biomarkers. Surrogate end point biomarkers are sought because the cancer develops over a long period of time, and studies of chemopreventives would require a huge number of subjects followed for many years. Surrogate end point biomarkers serve as alternative end points for examination of the efficacy of chemopreventives in tissue. High risk cohorts include women with cervical intraepithelial neoplasia (CIN) or squamous intraepithelial lesions (SIL). Nutritional studies have helped define micronutrients of interest (folate, carotenoids, vitamin C, vitamin E). Other medications of interest include retinoids (4-hydroxyphenylretinamide [4-HPR], retinyl acetate gel, topical all-trans-retinoic acid), polyamine synthesis inhibitors (alpha-difluoromethylornithine [DFMO]), and nonsteroidal anti-inflammatory drugs (ibuprofen). Phase I chemoprevention studies of the cervix have tested retinyl acetate gel and all-trans-retinoic acid. Phase II trials of all-trans-retinoic acid, beta-carotene, and folic acid have been and are being carried out, whereas Phase III trials of all-trans-retinoic acid have been completed and have shown significant regression of CIN 2 but not CIN 3. Phase I studies of DFMO and Phase II studies of DFMO and 4-HPR are underway. Surrogate end point biomarkers under study include (1) quantitative cytology and histopathology; (2) human papillomavirus type testing; (3) biologic measures of proliferation, regulation, differentiation, and genomic instability; and 4) fluorescence spectroscopic emission. Clinical trials with biologic end points will contribute to our understanding of the neoplastic process and hence aid us in developing new preventive and therapeutic strategies.

Molecular biology of cervical cancer and its precursors

Cervical cancer develops from well-defined precursor lesions referred to as either cervical intraepithelial neoplasia or squamous intraepithelial lesions. It is now known that specific types of human papillomaviruses (HPV) are the principal etiologic agents for both cervical cancer and its precursors. The high-oncogenic-risk HPV types associated with invasive cervical cancer produce two oncoproteins, designated E6 and E7, which interact with endogenous cell cycle regulatory proteins, including p53 and Rb. The interaction of virally derived and endogenous cellular proteins converges in deregulation of cell cycle progression and appears to be critical for the development of cervical cancers. However, the development of cervical cancer is a multistep process that cannot be explained simply by infection with specific types of HPV. One additional event that appears to play a role in tumor progression is integration of HPV DNA into the host genome. Integration of HPV DNA frequently disrupts the E2 open reading frames, resulting in overexpression of the E6 and E7 oncoproteins and possibly causing genomic instability. Additional cofactors and mutational events may be important in the pathogenesis of invasive cervical cancers and may include chromosomal rearrangements, loss of constitutional heterozygosity, and proto-oncogene activation.

Cervical cancer: is herpes simplex virus type II a cofactor?

In many ways, cervical cancer behaves as a sexually transmitted disease. The major risk factors are multiple sexual partners and early onset of sexual activity. Although high-risk types of human papillomaviruses (HPV) play an important role in the development of nearly all cases of cervical cancer, other sexually transmitted infectious agents may be cofactors. Herpes simplex virus type 2 (HSV-2) is transmitted primarily by sexual contact and therefore has been implicated as a risk factor. Several independent studies suggest that HSV-2 infections correlate with a higher than normal incidence of cervical cancer. In contrast, other epidemiological studies have concluded that infection with HSV-2 is not a major risk factor. Two separate transforming domains have been identified within the HSV-2 genome, but continued viral gene expression apparently is not necessary for neoplastic transformation. HSV infections lead to unscheduled cellular DNA synthesis, chromosomal amplifications, and mutations. These observations suggest that HSV-2 is not a typical DNA tumor virus. It is hypothesized that persistent or abortive infections induce permanent genetic alterations that interfere with differentiation of cervical epithelium and subsequently induce abnormal proliferation. Thus, HSV-2 may be a cofactor in some but not all cases of cervical cancer.

HPV and p53 in cervical cancer

OBJECTIVE

To determine the prevalence of HPV 16 and 18 E6 by DNA detection and p53 abnormal protein expression in cervical cancers in Hong Kong.

MATERIALS AND METHODS

Seventy-three squamous cell cervical cancer biopsy were analysed. Detection of HPV DNA was carried out by the polymerase chain reaction and Southern blotting (PCR/SB) technique using primers to the HPV16 & 18 E6 region and consensus primers to the L1 region. Abnormal expression of the p53 protein was detected by immunohistochemical staining (IHS) using the antibody CM1 on frozen sections of 55 cervical cancer samples. Forty-six samples were analysed for both the presence of HPV DNA and abnormal expression of p53.

RESULTS

67.2% of the 64 samples showed the presence of HPV 16 E6 DNA and 39.1% showed the presence of HPV 18 E6 DNA. 32.8% showed the presence of both HPV 16 and 18 E6 DNA. No HPV DNA was shown in 10.9% of samples. Only 3.6% (2) of 55 samples showed positive IHS with CM1. One occurred in a HPV negative sample and the other in a HPV positive sample.

CONCLUSION

A high prevalence of HPV DNA was detected in cervical cancer in Hong Kong using the PCR/SB technique. However, abnormal expression of p53 was uncommon amongst patients with or without HPV 16 or 18 infection.

Detection of the BC 24 transforming fragment of the herpes simplex virus type 2 (HSV-2) DNA in cervical carcinoma tissue by polymerase chain reaction (PCR)

The polymerase chain reaction (PCR) was used to investigate samples from Indonesian and Swedish patients with cervical intraepithelial neoplasia grade III (CIN III), squamous cell carcinoma or adenocarcinoma of the cervix for the presence of a transforming fragment (BC 24) of herpes simplex virus type 2 (HSV-2) DNA. The PCR test for HSV-2 DNA was more sensitive than the infectivity endpoint titer in a cell culture system and no cross reactivity was found with either varicella-zoster virus, cytomegalovirus, Epstein-Barr virus, human papillomavirus 16 or 18, or human genomic DNA. Using this PCR test, 2 out of 5 cases with CIN III, 10 of 71 squamous cell carcinomas, and 3 of 11 adenocarcinomas of the uterine cervix were found to contain DNA sequences homologous to the BC 24 fragment of the HSV-2 genome. Only two of the samples containing this transforming region of the HSV-2 DNA were positive in a PCR assay for the HSV-2 DNA polymerase gene. The great majority of the HSV-2 BC 24 DNA positive (12 of 15) came from the Indonesian group of patients. All 15 CIN III or cancer samples positive for the HSV-2 BC 24 fragment were also positive for papillomavirus DNA. In line with observations made by others, our data support the hypothesis that HSV infection could represent one of several possible oncogenic cofactors leading to cervical carcinoma. The HSV cofactor might be more important in the Indonesian than in the Swedish population.

Oncogenes, tumor suppressors and viruses in oral squamous carcinoma

The pathogenesis of oral squamous cell carcinoma involves recognised carcinogens in tobacco and/or alcohol but other factors, including viruses, may also have a role. This paper reviews the gene changes revealed in oral carcinoma, the evidence implicating viruses, and mechanisms whereby viruses may affect gene function.

Human herpes simplex-1 and papillomavirus type 16 homologous DNA sequences in normal, potentially malignant and malignant oral mucosa

We have tested a range of normal, potentially malignant and malignant oral mucosal biopsies tissues by Southern blot hybridisation analysis for the simultaneous presence of HSV-1 and HPV type 16 DNA sequences, both of which have been implicated as risk factors in oral carcinogenesis. The results show that: (1) 2/4 patients with lichen planus, 2/4 patients with non-specific keratosis, 1/8 patients with oral carcinoma and 3/5 biopsy specimens of normal oral mucosa contained DNA sequences homologous to the HSV-1, Bam HI-G fragment. (2) HPV-16 homologous DNA sequences were detected in 3/4 patients with lichen planus, 4/4 non-specific keratosis, 4/8 oral carcinomas and in 3/5 biopsy specimens of normal oral mucosa. (3) Overall, only 5 patient biopsy specimens were positive for both HSV-1 and HPV-16 homologous DNA sequences; 2 lichen planus, 2 non-specific keratosis and 1 normal. The data cannot exclude a "hit and run" oncogenic mechanism for HSV but suggest that if HSV-1 and HPV-16 play a synergistic role in the development of oral cancer this may be an early event. Indeed, the data suggest HSV might be more frequently found in potentially malignant lesions than in carcinoma.

C-myc oncogene expression in anal squamous neoplasia

AIMS

To determine the pattern of c-myc oncogene expression in anal squamous neoplasia and to determine if this could be used as a marker of disease progression.

METHODS

The presence and localisation of the c-myc gene product p62 in archival specimens of anal squamous epithelium, normal and neoplastic, was examined using immunohistochemical staining with the monoclonal antibody Myc1-6E10. Ten normal and epithelia, 10 anal intraepithelial neoplasia (AIN) III, and 31 anal squamous cancers were examined.

RESULTS

There was a noticeable difference between the staining characteristics of invasive tumours, normal anal epithelium, and AIN III. Intense, diffuse, mixed nuclear and cytoplasmic (n = 14) and exclusively nuclear (n = 8) staining in 22 of 31 (71%) of invasive anal tumours was observed. All positively staining tumours were well differentiated histologically, while the negatively staining nine of 31 (29%) were poorly differentiated (n = 7) and moderately well differentiated (n = 2). In six positively staining tumour sections adjacent areas of AIN III and non-dysplastic anal epithelium had staining characteristics similar to those of the invasive component. Staining in both normal anal epithelium (4/10) and AIN III specimens obtained from patients without a history of invasive disease (8/10) was less intense, focal in distribution, and exclusively nuclear. No difference in staining characteristics could be detected in these two groups.

CONCLUSIONS

The results of this study suggest that c-myc oncogene expression is implicated in the pathogenesis of anal squamous neoplasia, and that immunohistochemical staining for c-myc protein may be helpful in identifying those AIN III lesions most likely to progress to invasive tumours.

Detection of human papillomavirus genome and analysis of expression of c-myc and Ha-ras oncogenes in invasive cervical carcinomas

Invasive carcinomas of the uterine cervix of 38 patients were examined for the presence of human papillomavirus (HPV) genomes and for the state of the c-myc and Ha-ras oncogenes. A combination of Southern blot hybridization and polymerase chain reaction revealed the presence of the genome of HPV type 16 in 17 tumors (45%), that of HPV type 18 in 3 tumors (8%), and that of unknown types in 16 others (42%), while no viral DNA sequences were detected in 2 tumors. Of the 38 tumors, c-myc amplification was found in only 1 tumor, while there was no Ha-ras amplification. Overexpression of the c-myc gene was observed in 15 (44%) of the 34 tumors analyzed, while there was no overexpression of Ha-ras. Of the 23 squamous cell carcinomas analyzed, relapse-free rates at 24 months were 55% in tumors with c-myc overexpression and 100% in case of tumors with no c-myc overexpression, respectively. The results suggest the possibility that activation of the c-myc oncogene is involved in tumor progression.

Herpes simplex virus induces unscheduled DNA synthesis in virus-infected cervical cancer cell lines

We evaluated herpes-simplex-virus-type-2(HSV2)-induced unscheduled DNA synthesis in virus-infected cervical cancer (HeLa, CaSki, C-33A, and SiHa) cells. HSV2 replication was approximately 100-fold more efficient in the HeLa cells than in less susceptible C-33A and SiHa cells. In dual parameter flow cytometric analysis of bromodeoxyuridine (BrdU) incorporation, HSV2-infected HeLa cells showed a rapid increase in the proportions of DNA-synthesizing G1- and S-phase cells, whereas in C-33A and SiHa cells, the proportions of DNA-synthesizing G1- and early S-phase cells were increased late in the infection. Blocking of HSV2 replication by phosphonoformate inhibited virus-induced changes in HeLa cells, but not in C-33A and SiHa cells. Anti-BrdU antibodies exhibited a coarse globular nuclear staining pattern in the C-33A cells, while the other cells showed speckled and/or fine globular nuclear fluorescence. Anti-ICP8 (HSV-specified major DNA-binding protein) antibodies revealed that, in C-33A cells, ICP8 remained in the cytoplasm, whereas in the other cells, speckled or globular nuclear fluorescence was found. Our results showed that HSV2 induced the unscheduled synthesis of cellular DNA, which was host-cell-dependent, and in virus infected C-33A cells, it may be attributable to both viral and cellular proteins.

Herpes simplex virus and human papillomavirus sites correlate with chromosomal breakpoints in human cervical carcinoma

The distribution of 1,912 breakpoints observed in a series of 148 cervical cancers was analyzed. Fifty bands were shown to be nonrandomly involved in chromosome structural rearrangements. One hundred thirty-three breaks were noted in bands known to contain a human papillomavirus integration site, and 454 breaks were noted in bands containing a herpes simplex virus breakage site. We suggest that herpes simplex viruses and, possibly, papillomaviruses play an important role in the carcinogenesis and/or development of cytogenetic abnormalities in cervical cancers.

Oncogenes in gynecological tumors

Evidence is increasing that proto-oncogenes and cancer suppressor genes are involved in the development and/or progression of gynecological malignancies. While histopathologic examination remains an indispensable tool of the surgical pathologist in the diagnosis and evaluation of patients with gynecological malignancies, the advancement to technology and the development of new knowledge regarding neoplastic transformation are providing a basis for new opportunities to improve patients care. These new opportunities will depend on the use of the skills and reagents developed in the basic medical science laboratories. Thus, it is important for those in the field of diagnostic pathology to begin to acquire a knowledge of proto-oncogenes and cancer suppressor genes as well as a basic understanding of the techniques used to detect and evaluate them.

Viruses in the aetiology of oral carcinoma? Examination of the evidence

This paper examines the evidence for an aetiological role for viruses in the development of oral carcinoma. Several viruses have been sought in oral cancer and evidence found for some, particularly herpes simplex and human papillomavirus. However, the evidence also suggests that these viruses are ubiquitous agents and a number of criteria must be met before these potentially oncogenic agents can reliably be implicated in human carcinogenesis. In contrast, there is no evidence that viruses such as adenovirus, Epstein-Barr virus, and retroviruses play any role in oral carcinogenesis.

Human papillomavirus and c-myc/c-erbB2 in uterine and vulvar lesions

The aim of this study was to investigate papillomavirus (HPV)-DNA in precancer and cancer of the cervix, vulva, and endometrium by in situ/dot blot/Southern blot hybridization and polymerase chain reaction (PCR). Myc/erbB-2 expression was examined by Northern blot analysis. PCR was the most sensitive HPV detection method, demonstrating HPV-DNA in all pre-invasive and invasive cervical lesions (n = 21) and most (3 of 4) vulvar carcinomas in contrast to an overall rate of 60% with other techniques. Particular phenotypes (adenoid cystic/basal cell carcinoma of the vulva, cervical adenocarcinoma) were found to contain HPV. Endometrium harboured HPV not only in two cases of cervical cancer, but also in 3 of 8 primary endometrial carcinomas and 3 of 8 non-malignant conditions. Myc activation was confined to three squamous cell carcinomas, most markedly in one HPV-6-positive verrucous variant. ErbB-2 over-expression was only seen in one HPV-18 infected advanced endometrial tumour. Our findings point to a range of HPV-infected lesions broader than previously supposed and possible contributions of HPV-independent molecular events to carcinogenesis in this field.

Endocervical carcinoma and precursor lesions: c-myc expression and the demonstration of field changes

The monoclonal antibody Myc 1-6E10 was used in an immunocytochemical technique to examine the expression of the c-myc oncogene in normal endocervices and those with glandular intraepithelial neoplasia and invasive malignancy. Eleven of 14 normal endocervical biopsy specimens did not express the gene, while three showed nuclear, or light basal cytoplasmic localisation of the gene product, or both. All but one of 14 cases of low and high grade glandular intraepithelial neoplasia, and all 17 cases of invasive adenocarcinoma, showed a pan-cellular pattern of immunostaining. Of considerable additional interest was the demonstration of field changes in morphologically normal glandular epithelium in those biopsy specimens with concurrent cervical glandular intraepithelial neoplasia or adenocarcinoma. This was manifest as increased concentrations of myc proteins compared with normal tissues. These results further support the role of the c-myc gene in oncogenesis, and in the light of field changes, suggest possible difficulties in the clinical management of this group of patients.

Is vestibular papillomatosis associated with human papillomavirus?

The origin and clinical significance of vestibular papillae were evaluated by comparing histological features with the presence of human papillomavirus (HPV) types 6/11 and 16/18, as revealed by Southern blot DNA hybridization. Twenty women with vestibular papillomatosis underwent clinical evaluation and follow-up. When available, male partners were also examined. Histological changes suggestive of HPV infection were present in all the 20 specimens. Sixteen cases (80%) contained DNA sequences homologous to the viral probes. In particular, 12 cases (60%) reacted with the HPV 16/18 probe. Follow-up for more than 18 months revealed no variation in the distribution and appearance of vestibular papillae. No male partner showed signs of HPV lesions. The study shows that HPV 16 is frequently associated with vestibular papillae but does not support a productive infection. Therefore the most appropriate management of these patients should be evaluated clinically in each individual case.

Mutagenesis occurring following infection with herpes simplex virus does not require virus replication

Infection of eukaryotic cells in culture with herpes simplex virus type-1 (HSV-1) or HSV-2 increased the mutation frequency of the supF gene carried on the shuttle vector pZ189 by around sixfold. The increase was apparent 2 hr postinfection and reached a peak after 8 hr. To investigate this mutagenesis, plasmids pCKRR1 and pCKRR2 were constructed to express the large and small subunits, respectively, of HSV-2 ribonucleotide reductase (RR) under the control of the inducible mouse metallothionein promoter. Expression from these plasmids, either singly or together, had no effect on the mutation frequency of pZ189 under conditions when virus RR activity was detected. The HSV-1 temperature sensitive (ts) mutant viruses ts 1207 and ts 1222, which have ts lesions in the genes encoding R1 and R2, respectively, were as mutagenic as wild-type HSV-1 at both the permissive and nonpermissive temperatures. These results indicate that expression of HSV RR is not mutagenic in this system. Experiments using other HSV-1 mutants and ultraviolet-inactivated virus localized the cause of the increased mutagenic frequency either to a component of the incoming virion or to an effect exerted by the virus DNA itself. The present study confirms previous reports that infection with HSV exerts a mutagenic effect. Further, virus replication and gene expression were not required for the mutagenic effect studied here. This may have implications for a role of HSV in cellular transformation, as a nonproductive infection could mutagenize cellular genes.

Cytogenetic findings in cervical carcinoma. A statistical approach

Cytogenetic analysis with banding techniques was attempted in 150 cervical carcinomas, including in situ carcinoma, large cell keratinizing tumors, large cell nonkeratinizing tumors, small cell nonkeratinizing tumors, and adenocarcinomas. Monte Carlo simulations were used to determine which numerical and structural aberrations were nonrandomly involved in the tumorous process and to attempt to correlate specific abnormalities with specific histologic types. Results showed that several chromosomes are nonrandomly involved in cervical carcinomas and that some are more specifically associated with particular histologic subtypes. Therefore, cervical carcinoma appear to include a large spectrum of malignancies, each particular histologic type involving different genes. If some cytogenetic changes may be considered general events related to the carcinogenesis process, other rearrangements are presumably more specific processes arising in more committed stem cells.

Oncogene expression in cervical intraepithelial neoplasia and invasive cancer of cervix

Expression of the oncogenes Ha-RAS, c-MYC, and ERB-2 was investigated with an automated image analysis system in 12 specimens of normal cervix, 10 of cervical intraepithelial neoplasia (CIN) grade 1, 24 of CIN 3, and 10 of invasive cancer of the cervix. There was amplification of all three oncogenes in CIN 3 and invasive cancer compared with normal cervix and CIN 1. The difference was most pronounced with an antibody to the RAS p21 protein, with no overlap between CIN 3 and the normal range. This method might be useful in screening for cervical neoplasia, and for the determination of which CIN lesions require treatment.

HSV-2-induced tumorigenicity in HPV16-immortalized human genital keratinocytes

A subgenomic region of HSV-2, BglII N, is capable of converting immortal genital epithelial cells containing integrated HPV16 sequences into tumorigenic squamous cell carcinoma cells. Moreover, tumor-derived cultured cells and immortal cells that had been transfected with HSV-2/Bg/II N and kept in continuous culture subsequently lost the HSV-2 sequences. The HSV-2/Bg/II N sequence was ineffective on normal cells. Thus, HSV-2/Bg/II N may act as a cofactor in the genesis of a carcinoma but is not required to maintain the transformed phenotype. Although papillomaviruses (HPVs) are currently receiving much attention because of their association with cervical squamous carcinomas, ample reasons exist to suggest a multifactorial etiology in which additional factors are necessary to convert dysplastic lesions to carcinomas. The hypothesis that specific HPV types may be necessary but not sufficient to cause cancer is reinforced. Thus, HSV-2-transforming sequences have a potential role in the etiology of human cervical cancer.

Mapping of linear epitopes of human papillomavirus type 16: the L1 and L2 open reading frames

Certain types of human papillomavirus (HPV), notably HPV type 16, are associated with flat or inverted proliferative lesions of the cervix uteri that can progress to malignancy. As a first step towards the serological study of the epidemiology of HPV, we have synthesized the entire amino acid sequences of the 2 major viral capsid proteins of HPV type 16, L1 and L2, as a set of 66 synthetic 20-residue peptides with an overlap of 5 amino acids. The peptides were tested for reactivity with IgA, IgG and IgM antibodies in the sera of 30 patients with HPV-16-carrying cervical neoplasms. Both IgG and IgM antibody responses were detected, but most of the reactivity found was of the IgA class. The most immunoreactive peptides were further analyzed for reactivity with sera from 22 patients with parotid gland tumors and with sera from 38 healthy individuals. The L2-encoded protein contained only one major linear epitope, which was not specific for HPV-16-carrying neoplasms. In contrast, the L1-encoded protein contained several epitopes that were regularly immunoreactive with antibodies present in the sera of patients with HPV-16-carrying cervical neoplasms, but only rarely so in the sera of patients with other tumors or of healthy individuals.

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

The prevalence of human papilloma virus (HPV) types 6, 11, 16 and 18 was investigated using the polymerase chain reaction on formalin fixed, paraffin wax embedded material in 19 cases of cervical squamous cell carcinoma and in 10 normal cervices. HPV DNA was detected in 16 of 19 carcinomas, with multiple types present in 11 of these. HPV 16 or 18, or both, were present in all cases in which HPV was shown. Six of 10 cases of normal cervix contained HPV; five of these contained two or more HPV types, including HPV 16 or 18, or both. This study shows the feasibility of using the PCR on paraffin wax embedded material and indicates a high rate of carriage of multiple HPV types in both normal and neoplastic cervix.