Human papillomavirus type 16 in multifocal neoplasia of the female genital tract

We examined lesions from six women with multifocal neoplasia of the lower genital tract (vulva and cervix or vulva and vagina) for the presence of human papillomavirus (HPV) DNA sequences by DNA-DNA in situ hybridization. Cervical tissue specimens from four of the five women with carcinoma in situ (CIS) of the cervix were found to contain HPV type 16 DNA sequences. Vulvar lesions from three of these women also contained HPV-16 DNA and were histologically consistent with CIS. In each instance, hybridization with HPV-16 DNA probes was seen only in areas of the epithelium that contained evidence of surface maturation or koilocytotic atypia (KA). The HPV DNA was not visualized in regions of these lesions in which the full thickness of the epithelium was occupied by poorly differentiated cells. Virus capsid antigens were only detected in a very few cells in two of the four cervical lesions that contained HPV-16 DNA. HPV type 16, which has consistently been associated with the development of cervical cancer, is further implicated as an agent in the pathogenesis of genital cancers by demonstration of the virus genome in neoplasia at nonadjacent sites.     

Expression of cytokeratin polypeptides in human papillomavirus (HPV) lesions of the uterine cervix: 1. Relationship to grade of CIN and HPV type

A series of 74 punch biopsies, derived from 513 women prospectively followed for cervical human papillomavirus (HPV) infections (including HPV-NCIN, HPV-CIN I, HPV-CIN II, and HPV-CIN III lesions), and 43 control cases (consisting of normal epithelia, nonspecific cervicitis, and classical CIN lesions) were analysed for expression of cytokeratin polypeptides using the ABC technique and monoclonal antibodies SK 56-23 (wide-spectrum antibody), SK 60-61 (specific for keratins 8 and 18), and SK 2-27 (detecting keratins 14, 16, and 17). HPV typing was carried out using the in situ hybridization technique with DNA probes for HPV 6, 11, 16, 18, and 31. All layers of the exocervical epithelium were regularly stained with the antibody SK 56-23, and the staining pattern remained unaltered in all cervical lesions studied. In contrast to the normal exocervical epithelium, which remained negative with SK 60-61, positive staining was observed in 3 of 15 cervicitis cases and 6 of 23 classical CIN lesions. Interestingly, the majority (69 of 74, 93.2%) of both HPV-NCIN and HPV-CIN lesions showed positive staining with this antibody either in all layers or in suprabasal cells. Antibody SK 2-27 stained the basal cells of the normal exocervical epithelium with remarkable specificity. In 18 of 19 HPV-NCIN lesions, basal cells could not be stained by SK 2-27 monoclonal, but the suprabasal cells were stained instead. In HPV-CIN, but not in classical CIN, this antibody demonstrated the presence of the epitope typical of the cytokeratins 14, 16, and 17 in all layers of the epithelium, the highest frequency (9 of 12, 75%) being found in HPV 16-induced lesions. These disturbances of cytokeratin patterns in cervical epithelium could be associated with cell transformation by HPV, leading to development of HPV-CIN, and could be specific for this virus. The present data are of interest in assessing the stage of maturation of the squamous cells in progressing cervical HPV infections.     

Detection of human papillomavirus DNA in human cervical lesions by tissue in situ nucleic acid hybridization

Cervical cancer is one of the most common female cancers in Taiwan. Certain types of human papillomavirus (HPV) are frequently detected in the epithelial precancerous and cancerous lesions of the cervix. By the use of tissue in situ hybridization, we investigated the relationship of various types of HPV (group I, HPV-6 & 11, group II, HPV-16 & 18, group III, HPV-31, 33 & 35) with cervical condyloma, carcinoma as well as precancerous lesions. Group I HPV DNAs were mainly found in cervical condylomatous lesions (2/2) of the cervix and cervical intraepithelial neoplasia I (CIN I) (2/4), but were only occasionally found in CIN II (1/4), CIN III (1/9) or non-keratinized squamous cell carcinoma (1/15). HPV DNAs of groups II and III were mainly detected in lesions of CIN III (5/9) and invasive squamous cell carcinoma (large cell, keratinized type: 4/7; large cell, non-keratinized type: 11/15). HPV DNA sequences were invariably detectable only in the cell nuclei of condyloma or dysplastic epithelium or invasive carcinoma. However, they could not only be detected in the upper layer dysplastic cells and koilocytes but also in the well and poorly differentiated cervical cancer cells. The distribution of HPV DNA positive cells in the carcinomas fell into four different patterns: (1) upper zone and non-invasive regions of the carcinoma (11/22, 50%), (2) basal zone and invasive regions (2/22, 9%), (3) randomly scattered (7/22, 32%), and (4) extensively distributed over the whole tumor lesions (2/22, 9%). Thus, our results are consistent with a strong correlation between the presence of HPV-16, 18, 31, 33 and 35 and malignant conversion of cervical epithelial cells.     

Human papillomavirus DNA in adenocarcinoma in situ, microinvasive adenocarcinoma of the uterine cervix, and coexisting cervical squamous intraepithelial neoplasia

Previously, human papillomavirus (HPV) DNA, mainly HPV-18 DNA, was detected in more than 40% (17/40 cases) of invasive adenocarcinoma of the uterine cervix in our laboratory. In order to identify HPV DNA in the precursor lesions of adenocarcinoma of the cervix, 11 cases of adenocarcinoma in situ containing microinvasive adenocarcinoma and 10 cases of adenocarcinoma in situ were studied for the presence of HPV DNA by in situ hybridization using highly sensitive 3H-labeled HPV-16 and HPV-18 DNA probes. HPV types present in cervical squamous intraepithelial neoplasia (CIN) coexisting with adenocarcinoma in situ and microinvasive adenocarcinoma were also studied. Apart from the coexisting CIN II-III with glandular neoplasms, 48 cases of CIN III (severe dysplasia and squamous carcinoma in situ) removed by conization or hysterectomy and known to be free of adenocarcinoma were used for comparison. HPV DNA was detected in 64% of microinvasive adenocarcinoma, 70% of adenocarcinoma in situ, and 63% of the control CIN III. HPV-18 DNA was the preponderant type of HPV DNA found in adenocarcinoma in situ and microinvasive adenocarcinoma. All cases of HPV DNA-positive microinvasive adenocarcinoma contained the same type of HPV DNA as the lesions of coexisting adenocarcinoma in situ. CIN coexisting with microinvasive adenocarcinoma or adenocarcinoma in situ contained the same type of HPV as identified in the glandular lesions, whereas all of the HPV DNA-positive control CIN III cases contained HPV-16 DNA. These results suggest that adenocarcinoma in situ is a precursor lesion of adenocarcinoma of the cervix that contains HPV DNA, and that CIN coexisting with adenocarcinoma may be a result of a metaplastic process of adenocarcinoma or of bidirectional differentiation of the affected reserve cells.     

Prevalence of human papillomavirus types 16 and 18 in cervical adenocarcinoma and its precursors in Scottish patients

Our aim was to determine the prevalence of human papillomavirus (HPV) types 16 and 18 in cervical adenocarcinoma (and its precursors) in Scottish patients. Nucleic acid was extracted from paraffin-embedded, formalin-fixed tissues. We examined 119 cases of invasive adenocarcinoma, 20 cases of adenocarcinoma in situ, and 16 cases of normal glandular epithelium. HPV DNA was detected by polymerase chain reaction using type-specific primers for the E6 and E7 genes of HPV-16 and HPV-18 with conformation of HPV genotype by subsequent restriction fragment length polymorphism. HPV DNA was identified in 87 (62.6%) cases, with HPV-16 being detectable in 65 (47%) cases and HPV-18 in 41 (29%) cases. All the cases of normal tissue tested negative for HPV-16 and/or HPV-18. No significant relation between infecting HPV type (16 or 18) and subtypes of disease (within the invasive category and between the preinvasive and the invasive categories) was noted. Our findings support that HPV-16, along with HPV-18, are likely to play a significant role in the pathogenesis of cervical adenocarcinomas and that cervical cancer screening strategies that incorporate oncogenic HPV testing, and prophylactic vaccines that target these types, will be beneficial for the reduction of adenocarcinoma and associated glandular precursors.     

Detection of human papillomavirus DNA in cervical lesions by in situ hybridization using biotinylated DNA probes

In situ hybridization (ISH) for human papillomavirus (HPV)-6, -11, -16, -18, and -31 DNA was performed on 615 formalin-fixed paraffin-embedded cervical biopsies using biotinylated DNA probes. Results were obtained from 584 samples with 266 (45.5%) containing HPV-DNA sequences. Ninety percent of condyloma acuminatum specimens were positive for HPV-DNA with 18 of 19 positive cases containing HPV-6 or -11 DNA. The detection rate of HPV in cervical intraepithelial neoplasia (CIN) lesions was 50.6% (239 of 472), while only 8 of 91 (8.9%) cervical biopsies considered to be histologically normal or with minimal dysplasia contained HPV-DNA as demonstrated by ISH. The prevalence of HPV-16, -18, and/or -31 DNA increased with the severity of the lesions, with 20 of 20 (100%) positive CIN-III lesions containing these viral types compared with 102 of 157 (65.0%) positive CIN-I lesions. ISH with biotinylated DNA probes appears helpful in identifying lesions containing higher risk viral strains.     

Presence of Oncogenic HPV DNAs in Cervical Carcinoma Tissues and Pelvic Lymph Nodes Associating with Proliferating Cell Nuclear Antigen Expression

The presence of oncogenic HPV DNAs (HPV-16/18) in cervical carcinomas and their normal and metastatic pelvic lymph nodes and the expression patterns of proliferating cell nuclear antigen (PCNA) in cervical carcinomas were retrospectively studied to elucidate the possible roles of them in malignant transformation and progression of the disease. HPV-16/18 DNAs were detected by polymerase chain reaction using HPV E6 type-specific primers in 79 patients with cervical cancer: 31 patients who had pelvic lymph node metastasis (group I) and 48 patients without pelvic lymph node metastasis (group II) who were proven by pathologic examination of surgical specimens. HPV-16 or -18 DNAs were detectable in cervical carcinoma tissues in 60 patients from 79 cervical cancer patients (75.9%; HPV-16 was 67.1% and HPV-18 was 8.9%). HPV DNAs were amplified from metastatic pelvic lymph nodes in 13 patients of group I (42%) and from nonmetastatic lymph nodes in 7 group I patients (22.5%). Recurrence was identified in 9 group I patients (29.0%) in 3 years of follow-up. HPV DNAs were amplified from nonmetastatic lymph nodes in 11 group II patients (22.9%). Two group II patients, who had HPV-16 DNA by PCR in nonmetastatic nodes, were recurrent. PCNA was overexpressed in 66.7% of HPV-16- or -18-positive cervical cancers and 16.7% of HPV-16- or -18-negative cervical cancers. However, the expression levels of PCNA in cervical cancers were not influenced by the presence of oncogenic HPV DNA or pathologic metastasis in the pelvic lymph nodes. In conclusion, HPV DNA could be amplified from some metastatic and nonmetastatic pelvic lymph nodes and the detectability of oncogenic HPV DNA in pelvic lymph nodes may represent the poor outcome in the treatment of disease. The expression of PCNA protein which was associated with presence of oncogenic HPV DNAs in cervical cancers, suggesting activation of S phase of cell cycle, may contribute to the malignant progression by HPV-16 or -18.     

Usefulness of PCR in situ hybridization as a technique for morphological detection of human papillomavirus in uterine cervical neoplasia

This study was designed in order to devise fitting conditions in polymerase chain reaction (PCR)-in situ hybridization (ISH) for observing human papillomavirus (HPV) infection morphologically in uterine cervical neoplasias and to compare the detection rates of HPV by PCR-ISH and solution phase PCR (S-PCR) as well as fluorescence ISH (FISH). Tissues were obtained from 23 patients with cervical intraepithelial neoplasia 3, who visited our hospital between 1994 and 1997. To detect HPV-16, a HPVpF forward primer and a HPVp 16 reverse primer were used. Compared with the traditional methods, the PCR-ISH technique performed in this study was contrived as follows. To prevent detachment, the specimens were attached to silane-coated slides at 90 degrees C and successively left at room temperature for 36 hours. In proteopepsis, pepsin was used. PCR products were fixed with 4% paraformaldehyde. PCR-ISH, S-PCR, and FISH showed HPV-16 positivity in 52.2%, 56.5% and 21.7%, respectively. The positive rate of HPV-16 detected by PCR-ISH as well as S-PCR was significantly higher than that by FISH (p<0.01, respectively). There was no significant difference between the positive rates of HPV-16 detected by PCR-ISH and S-PCR. HPV-16 was detected by S-PCR in all 12 specimens in which HPV-16 expression was judged as positive using PCR-ISH. Similarly, HPV-16 was found by PCR-ISH in all five specimens in which HPV-16 expression was regarded as positive using FISH. While the FISH technique detected HPV-16 signals only in the superficial and middle layers of squamous cells, the PCR-ISH technique demonstrated them in all the layers including the parabasal and basal layers. The PCR-ISH technique contrived in this study has a high sensitivity to HPV-16 equal to that of S-PCR. The difference in detection rate and distribution of HPV DNA between PCR-ISH and FISH might suggest that HPV does not infect the superficial layer but rather the parabasal layer.     

Rapid dysplastic transformation of human genital cells by human papillomavirus type 18

This study delineates differences in biologic activity between human papillomavirus (HPV) types 16 and 18. Human cervical and foreskin epithelial cells were cultured and transfected with recombinant HPV-16 and -18 DNA, resulting in immortalized cell lines. Normal epithelial cells as well as HPV-16 and -18 immortalized cells of both early passages (less than 40 population doublings) and late passages (greater than 180 population doublings) were transplanted in athymic mice. Normal squamous cells formed well-stratified epithelium, while HPV immortalized cells developed either normal-appearing epithelium or typical dysplastic changes. Dysplastic changes were seen in none of the 13 grafts with early-passage HPV-16 cell lines, while 9 of 14 grafts with early-passage HPV-18 cell lines developed dysplasias (P less than 0.0004). These results support previous clinical observations suggesting that HPV-18 may be associated with a more aggressive and rapidly progressive form of cervical neoplasia.     

Persistent papillomavirus type-31 and type-45 infections predict the progression to squamous intraepithelial lesion

ObjectiveHuman papillomavirus (HPV) has been recognized as the major etiologic agent of cervical squamous cell carcinoma. However, it has been demonstrated that HPV infection is usually a self-limited process and does not lead to significant epithelial lesions or cancer. Recent data indicate that persistent high-risk HPV (HR-HPV) infections have a significantly increased risk of developing incident high-grade cervical intraepithelial neoplasia and cervical cancer. Our aim, therefore, was to assess whether there exist HPV genotypes whose persistence can be considered powerful surrogates of a progressive disease. We retrospectively selected all patients with a negative cytological diagnosis or with atypical squamous cells of undetermined significance, with a positive test for HR-HPV, different from HPV types 16 and 18, and assessed the significance of the risk of progression based on the persistence of the specific HR-HPV.Materials and methodsWe retrospectively queried the database of our Colposcopy Clinic for all patients with a negative cytological diagnosis or with atypical squamous cells of undetermined significance and a positive test for HR-HPV, and we calculated the incidence of progression to lesions greater than or equal to low-grade squamous intraepithelial lesions after 6 months, according to the HPV type.ResultsA progression rate of 48.27% was found in patients tested positive for HPV-31 (Group 1), 38.46% in patients tested positive for HPV-45 (Group 2), and 5.73% in patients tested positive for HPV types other than HPV-16, HPV-18, HPV-31, and HPV-45 (Group 3).ConclusionOur data demonstrate that the persistence of HPV-31 and HPV-45 is strongly associated with the occurrence of squamous intraepithelial lesion.     

The possibility of viral etiology in cervical carcinogenesis

Oncogenic potential of herpes simplex virus type 2 (HSV-2) and human papillomavirus (HPV) which are both associated with occurrence of cervical cancer and the mechanism of oncogenesis by these viruses were investigated by transformation experiments in vitro. The results were obtained as follows. 1) HSV-2 induced neoplastic transformation of normal diploid cells is a multistep process. Cervical cancer associated antigen AG-4 is encoded within the specific region of HSV-2 DNA which converts immortalized cells to tumorigenic lines. 2) Tumor cells express cellular oncogene at a final stage of neoplastic transformation induced by HSV-2 and "hit and run" theory is applicable to oncogenesis of this virus. 3) Complete carcinogenesis can be mediated by HPV-16 or HPV-18 DNA under collaboration with other cofactors such as HSV-2. 4) It is suggested that neoplastic transformation induced by HPV-18 DNA is based on "hit and run" oncogenesis. 5) HPV-16 or HPV-18 DNA can immortalize primary diploid cells and convert them to fully tumorigenic phenotype by repeating cell passage. 6) It has been experimentally proved that the difference in transforming potential exists between HPV 6/11 and HPV 16/18. 7) Amplification and overexpression of c-myc oncogene was detected in transformed cells obtained by HPV-16 transfection. While overexpression of c-myc was detected in transformed cells induced by HPV-18 DNA, but no amplification was observed. On the other hand, detection of HPV, DNA and amplification or overexpression of protooncogenes was performed in cervical intraepithelial neoplasias (CIN) and invasive cervical carcinomas. The results were summarized as follows. 1) HPV DNA was detected in approximately 70% of a population with CIN by in situ hybridization. CIN II showed the highest incidence of positive HPV DNA (91%), and the positive ratio decreased in CIN III (56%). 2) Immunohistochemical study of paraffin-embedded specimens with monoclonal antibodies to oncogene products revealed that only some of cervical invasive carcinomas expressed c-myc protein, ras p21 or EGFR. 3) HPV DNA was detected in 46% of invasive cervical carcinomas by Southern blot hybridization. The percentage of patients with positive results for HPV 16/18 was 29%. However, it increased up to 58% by use of polymerase chain reaction (PCR), suggesting that there are many cervical cancer tissues in which a number of cells lack viral DNA. 4) Northern blot hybridization analysis revealed overexpression of c-myc mRNA in 30% of cervical invasive carcinomas although amplification of c-myc oncogene was detected in only one of invasive carcinomas.(ABSTRACT TRUNCATED AT 400 WORDS)     

Characterization of human papillomavirus genotypes and HPV-16 physical status in cervical neoplasias of women from northern Portugal

Objective

To determine human papillomavirus (HPV) genotypes and the physical status of HPV-16 DNA among women from northern Portugal with cervical lesions.

Methods

The present retrospective study included samples of cervical exfoliated cells from 88 women (median age 42.0 ± 13.1 years) who attended the Gynecology Service at the Portuguese Institute of Oncology in Porto during 2010. After DNA extraction, HPV genotyping was performed by polymerase chain reaction (PCR) followed by restriction fragment length polymorphism analysis using the MY09/MY11 primers. The physical status of HPV-16 was determined by real-time PCR.

Results

Overall, 69.3% of the samples tested positive. The prevalence of HPV infection was 38.5% in normal samples, 57.7% in cervicitis samples, and 87.2% in all cervical lesions including invasive cancers. Sixteen genotypes were detected, the most prevalent ones being HPV-16 (42.9%), HPV-31 (12.2%), and HPV-58 (10.2%); HPV-18 was rare. The overall prevalence of HPV-16 integration was 31.6%. The physical status of HPV-16 did not differ significantly by histology.

Conclusion

The most frequent genotypes were HPV-16, -31, and -58. Integration of HPV-16 DNA seemed to be an early event in cervical carcinogenesis. Further studies are required to clarify the value of viral integration as a prognostic marker.     

Occurrence of human papillomavirus DNA types 16 and 18 (HPV-16/18) in cervical smears as compared to cytological findings

Cervical smears from 2336 women were examined for the presence of HPV-16/18 by dot-blot hybridization using 32P-labeled HPV-16/18 DNA under high stringency conditions. The hybridization data were compared with cytological findings classified according to Papanicolaou. The ages of the patients ranged from under 20 to over 70 years. Ninety-eight (4.4%) of the 2237 cytologically normal cervical samples (Pap I and II) were HPV-16/18 positive. Thirteen out of 32 (40.6%) samples showing signs of mild and moderate dysplasia (Pap IIID) were found to be HPV-16/18 positive. In 5 out of 7 (71.4%) samples from women with severe dysplasia or carcinoma in situ (Pap IV) and in 9 out of 25 (32.1%) samples from patients with invasive cervical carcinoma (Pap V) HPV-16/18 DNA was detected. Thirty-two smears were from women with severe unspecific cervical inflammation (Pap III). Two (6.2%) out of them were HPV-16/18 positive. Normal smears showed an apparent age-dependent pattern of HPV-16/18 positivity with a peak prevalence of 10.6% among women younger than 20 years old. The majority of premalignant lesions was detected among women younger than 40 years old; whereas all invasive lesions were from women older than 39 years. Compared to the HPV-16/18 prevalence rate in normal smears, abnormal smears harbored HPV-16/18 DNA approximately 9 times more frequently. This finding supports the hypothesis that HPV-16/18 may be involved in the development of cervical cancer.     

HPV oligonucleotide microarray-based detection of HPV genotypes in cervical neoplastic lesions

BACKGROUND: In this study we examined the use of a new-human papillomavirus (HPV) detection method, the HPV oligonucleotide microarray system (Biomedlab Co., Korea), which we compared with the well-established HPV DNA detection system (Hybrid Capture II; HC-II, Digene Co.). This new method prompted us to develop a new HPV genotyping technique, using the oligonucleotide microarray, to detect the generic and type-specific sequence of HPV types. In particular, we undertook the evaluation of the clinical efficacy of the HPV oligonucleotide microarray for detecting HPV in cervical neoplastic lesions. METHODS: One hundred forty patients were involved and classified into three groups according to their histopathologic diagnoses: Group I (nonspecific chronic cervicitis; n = 61), Group II (low-grade squamous intraepithelial lesion (SIL); koilocytosis, and mild dysplasia; n = 39), and Group III (high-grade SIL; moderate, severe dysplasia and in situ carcinoma; n = 40). Cytological diagnoses were based on the Bethesda System and cervical samples were analyzed by the two methods. The HPV oligonucleotide microarray detected 15 types of high-risk HPV (HPV-16/-18/-31/-33/-35/-39/-45/-51/-52/-56/-58/-59/-66/-68/-69) and 7 types of low-risk HPV (HPV-6/-11/-34/-40/-42/-43/-44). RESULTS: In 105 of the 140 cervical samples (75%), HPV DNAs were examined using the HC-II method. HPV detection rates using the HPV microarray agreed with those of HC-II. One HC-II-positive, but HPV microarray-negative, case occurred in the low-grade SIL (Group II) and was later confirmed negative for HPV. The other HPV microarray-positive but HC-II-negative case was found to be HPV-18 by PCR. Low-risk types of HPV were detected in 3 of 39 low-grade SIL cases (Group II) using the HPV microarray. HPV-16 was the most frequent type (32.1%) in all specimens tested, and was significantly more frequent in low-grade or high-grade intraepithelial lesions (Groups II or III) than in normal controls (Group I) (P < 0.05). HPV-58 was the second most common type (17.5%) in Group III. The HPV microarray was found to have advantages in terms of identifying the HPV genotypes and cases of multiple HPV infection. Double HPV infections were detected in 12 cases and triple HPV infections in 7 cases. Two cases were positive for four types of HPV (HPV-16/18/33/35, HPV-16/18/58/68). The sensitivity of HPV testing (HC-II; 94.9%, HPV microarray; 93.7%) for identifying patients with squamous intraepithelial lesion was significantly better than the sensitivity of cytology (77.1%, P < 0.05). On using multiple logistic regression analysis to estimate the relative risk of SIL versus HPV type, HPV-16-positive cases were found to have a 7.5-fold risk of SIL (95% CI = 3.28-16.51; P < 0.01). HPV-33 and HPV-58 were found to be significantly related to high-grade SILs (P < 0.01). CONCLUSIONS: Our results suggest that the HPV oligonucleotide microarray is highly comparable to HC-II for detecting HPV in cervical specimens. The HPV oligonucleotide microarray provides useful information on viral genotype and multiple HPV infections in HPV-related cervical lesions. Genetic information on HPV in cervical specimens might be a particular benefit of the new procedure in the management of cervical neoplastic lesions     

Concept of the existence of human papillomavirus (HPV) DNA in histologically normal squamous epithelium of the genital tract should be re-evaluated

Because of the crucial importance of guiding current thinking in the field of HPV epidemiology, the concept of the existence of HPV DNA in histologically normal squamous epithelium was re-evaluated. A series of 102 randomly collected cervical punch biopsies, previously proved to contain the DNA of HPV types 6, 11, 16, 18, 31 or 33 by in situ hybridization were subjected to analysis for the localization of HPV DNA, i.e., whether found in the normal epithelium or at the lesion site only. This material consisted of a representative series of flat, endophytic and papillary HPV lesions with all histological grades from HPV-NCIN to HPV-CIN III, and the six HPV types in the same proportions as they occur in non-selected series of HPV lesions. Weak signals of HPV DNA were found in the basal cells in 6/102 (5.8%) of the biopsies. HPV DNA was constantly present in the parabasal cells in 25/102 (25.4%), in the intermediate cell layers in (98/102, 96%), and in the superficial cells of all 102 lesions. Noteworthy was the constant failure to reveal even weak signals of HPV DNA (of any of the six types) in histologically normal squamous epithelium of any of the 87 lesions, where such an epithelium was detectable. The present findings confirm our previous 'impression' that HPV DNA rarely if ever appears in the histologically normal squamous (or columnar) epithelium in the genital tract, when analysed using the in situ hybridization. Thus, great care should be exercised in interpreting results that suggest the discovery of HPV DNA in normal genital tract epithelium, unless based on firm documentation by in situ hybridization.     

Cervical glandular intraepithelial neoplasia topography and the risk of conisation

OBJECTIVES: The frequency of endocervical adenocarcinoma is increasing in comparison with squamous cell carcinoma and it presents a very difficult diagnostic and therapeutic problem. DESIGN: The aim of this study was: 1) Evaluation of topography of the cervical glandular intraepithelial neoplasia (CGIN) 2) An analysis of the Human Papillomavirus (HPV) infection rate in samples. MATERIALS AND METHODS: 360 amputated uterine cervix samples with histologically-proven diagnosis of cervical intraepithelial neoplasia (CIN-3) were evaluated. The coexistence of pre-invasive lesions in squamous epithelium and endocervical columnar cell were investigated. Moreover CGIN topography and retrospective histopathological analysis were determined. A polymerase chain reaction (PCR) was performed using commercially available PCR Human Papillomavirus Typing Set to detect HPV infection. RESULTS: Among 360 positive cervical intraepithelial glandular neoplasia samples (CIN-3) 71 (19.7%) showed coexisting glandular lesions (CGIN-1, 2, 3). The lesions in endocervical glandular cells of CIGN-type were distributed from the distance up to 14 mm from the surface of cervix. Most of them were located no deeper than 1 mm from the surface of canal epithelium. HPV DNA was found in more than 90 preneoplastic glandular proliferations. The frequency of oncogenic HPV-16 and 18 presence was higher than non-oncogenic HPV. CONCLUSIONS: 1. CIN-3 is associated in about 20% with cervical glandular intraepithelial neoplasia (CGIN). 2. Topography of CGIN is important in planning the management. 3. Most of CIGN are associated with HPV infection.     

Type IV collagen in the basal membrane of human papillomavirus associated premalignant and malignant squamous cell lesions of the uterine cervix

In the present study, the expression of type IV collagen associated with the basal membrane (BM) was studied histochemically (indirect immunoperoxidase-antiperoxidase) in cervical human papillomavirus (HPV) lesions (diagnosed using in situ DNA hybridization) of different grades. The expression of type IV collagen in premalignant epithelial lesions (HPV with and without cervical intraepithelial neoplasia) was identical with that in the BM of normal exocervical epithelium, in contrast to 60% (3/5) of carcinoma in situ lesions and 90% (10/11) of invasive carcinomas, where the staining pattern was interrupted and the staining intensity reduced. Thus, the expression of type IV collagen seems to remain unchanged during the entire spectrum of premalignant stages of cervical HPV lesions. This suggests that the squamous epithelial cells responsible for the formation of the BM are not affected by this virus at early stages of the disease, and immunohistochemical recognition of an intact staining pattern of type IV collagen may signify well-preserved basal cell function (confined to nonmalignant?) HPV-infected squamous epithelium.     

In situ hybridization study on the localization of HPV DNA in the precancerous lesions of uterine cervix

Human papillomavirus (HPV) types 16 and 18 have been found closely associated with cervical cancer. In order to investigate the relationship between HPV DNA and cervical precancerous lesions, we examined the formalin fixed specimens obtained from 22 cases of mild dysplasia, 33 cases of moderate dysplasia and 31 cases of severe dysplasia of the uterine cervix for the presence of HPV 6/11, 16 and 18 DNAs by in situ hybridization using the biotinylated HPV DNA probes. We also followed some HPV DNA positive cases of cervical dysplasia for more than 6 months prospectively. The results of in situ hybridization analysis revealed that HPV DNA was detected in the nuclei of koilocytosis, dysplastic cells and metaplastic cells. HPV 6/11 was positive in 27.3% (6/22) of mild dysplasia and 21.2% (7/33) of moderate dysplasia. On the other hand, HPV 16 positive rate increased with the grade of dysplasia and 36.4% (12/33) of moderate dysplasia, 61.3% (19/31) of severe dysplasia were positive for HPV 16 DNA. Some of the follow-up cases which were positive for HPV 16 DNA were later found to have carcinoma in situ. Our results suggest that HPV type 16 might play an important role in cervical carcinogenesis.     

Tissue effects of and host response to human papillomavirus infection

Human papillomaviruses are a heterogeneous group of DNA tumor viruses associated with hyperplastic (warts, condylomas), dysplastic (CIN and VIN), and malignant lesions (carcinomas) of squamous epithelium. Each HPV type is preferentially associated with specific clinical lesions and has an anatomic site preference for either cutaneous or mucosal squamous epithelium. Infection appears to begin in the basal cells. Early gene expression is associated with acanthosis, and late gene expression is associated with appearance of structural antigens and virions in nuclei of cells of the granular layer, usually koilocytotic cells. Malignant transformation of warts and papillomas appears to be related to a variety of factors: (1) infection by certain HPV types (HPV-5, HPV-8, HPV-16, HPV-18, HPV-31); (2) decreased cellular immunity to HPV-associated antigens; and (3) interaction with cofactors, such as other microorganisms or sunlight (see also the article by Kashima and Shah). Spontaneous regression or successful treatment of the benign lesions appears to depend on either naturally acquired or iatrogenically related stimulation of HPV type-specific immunity. The humoral antibody response to HPV particles may be important in preventing infection. In contrast, the local events surrounding regression of warts and condylomas are primarily associated with specific cell-mediated immunity. Local cell-mediated immune responses, particularly cell-associated soluble mediators and stationary macrophage-like cells, may be especially important in the host's immune response to mucosal infections.