Telomerase and human papillomavirus as diagnostic adjuncts for cervical dysplasia and carcinoma

Telomerase and human papillomavirus (HPV) DNA were evaluated as potential markers of high-grade dysplasia in cervical cytological specimens. Cytology specimens were collected from patients at the time of colposcopic evaluation for management of a previous abnormal cytology test result. Telomerase activity was evaluated by the telomeric repeat amplification protocol (TRAP), and HPV DNA was detected by polymerase chain reaction with L1 consensus-sequence primers and filter hybridization genotyping. Telomerase was detected in 8 of 97 (8.2%) cases with normal cytology or benign cellular changes, in 7 of 98 (7.1%) cases of atypical squamous cells of undetermined significance (ASCUS), in 3 of 95 (3.2%) cases of low-grade squamous intraepithelial lesion (LSIL), and in 17 of 48 (35.4%) cases with high-grade squamous intraepithelial lesion (HSIL). High-risk HPVs were detected in 23 of 97 (23.7%) cases with normal/reactive cellular changes (RCC) cytology, in 28 of 98 (28.6%) cases of ASCUS, in 69 of 95 (72.6%) cases of LSIL, and in 35 of 48 (72.9%) cases of HSIL. Telomerase expression did not correlate with the detection of high-risk HPVs in any cytological diagnostic categories. Telomerase and HPV test results of cytological specimens were correlated with the histological diagnoses of concurrent cervical biopsy specimens. Telomerase showed a sensitivity of 29.9% and a specificity of 94.0% for biopsy-confirmed cervical intraepithelial neoplasia (CIN) II/III. In contrast, high-risk HPVs were detected in 70.1% of cases with underlying CIN II/III, with a specificity of 62.5%. A relatively high proportion of normal/RCC or ASCUS cases with telomerase-positive test results had underlying high-grade dysplasia on cervical biopsy. Thus, technical and practical limitations of the TRAP assay in cervical cytology specimens limit the practical application of telomerase as a diagnostic adjunct in cervical cytopathology.     

Detection of human papillomavirus in urine and cervical swabs from patients with invasive cervical cancer

Despite the high prevalence of both human papillomavirus (HPV) infections and cervical cancer among Zimbabwean women, the ability to test for HPV infection of the uterine cervix is limited by a lack of an easy sample collection method that does not require gynecological examination. The presence of HPVs in urine and cervical swab samples collected from 43 women who presented with invasive cervical cancer was investigated. HPV detection was done by means of degenerate primers in a nested polymerase chain reaction (PCR). Typing of HPVs was done using restriction fragment length polymorphism (RFLP) analysis. HPV was identified and typed in 98% (42/43) of cervical swabs and 72% (31/43) of paired urine samples. HPV type 16 was the most common (25/42, 59%), followed by types: 33 (13/42, 31%), 18 (6/42, 14%), and 31 (1/42, 2%). Type-specific concordance between cervical and urine samples was high (22/28, 79%). Therefore, the HPV types identified in urine samples in most cases represent the same HPV type infecting the cervical epithelium. The results suggest that urine may be a practical sample for testing of HPV urogenital infection. Further research is required before the detection of HPV in urine can be applied in the routine cervical screening programs.     

Human papillomavirus infection of morphologically normal cervical epithelium adjacent to squamous dysplasia and invasive carcinoma

We have begun a systematic study of human papillomavirus (HPV) infection in colposcopically and/or morphologically normal epithelium of the uterine cervix. Paired biopsies were taken from the lesions (cervical intraepithelial neoplasia [CIN], condyloma, invasive carcinoma) and from the normal-appearing adjacent epithelium 3 to 5 mm from the edge of the lesion. Myometrium or ectocervical epithelium from patients who had undergone hysterectomy for reasons other than genital dysplasia or malignancy served as controls. One biopsy was examined histologically. DNA from the second biopsy was digested with Pst I, and the presence or absence of HPV was determined by Southern blotting using HPV-16 DNA as a probe. HPV was not detected in any of the 12 control samples. Of 30 patients with CIN and/or condyloma, five of 18 who were HPV-positive had either HPV-16 (three cases) or virus resembling HPV-31 (two cases) in the lesion and adjacent epithelium. Of seven patients with invasive carcinoma, four had HPV in the lesion and adjacent epithelium; two of these four patients had typical HPV-16. Such infection of apparently normal epithelium has major implications for our understanding of the pathogenesis, treatment, and follow-up of patients with cervical neoplasia.     

P16 overexpression and human papillomavirus infection in small cell carcinoma of the uterine cervix

Carcinogenesis of cervical cancer has been investigated, and p16(INK4a) overexpression in squamous cell carcinoma of the cervix has been reported as a result of infection by human papillomavirus (HPV) (eg, HPV 16), and the consequence of the retinoblastoma (Rb) protein inactivation by HPV E7 protein. However, to our knowledge, there have been no studies on the relation between p16(INK4a) overexpression associated with HPV and small cell carcinoma of the cervix, which behaves more aggressively clinically than squamous cell carcinoma. The purpose of this study was to determine whether p16(INK4a) is overexpressed in small cell carcinoma, and if p16(INK4a) is overexpressed, the types of HPV that are related to this cancer. We reviewed 10 cases of small cell carcinoma and examined them for p16(INK4a) overexpression by immunohistochemistry. We also performed HPV typing with polymerase chain reaction (PCR)-sequencing analysis and in situ hybridization and found that p16(INK4a) was overexpressed in every case. PCR-sequencing analyses revealed that all cases were HPV-positive and that 9 cases were positive for HPV 18. Five of the 9 cases positive for HPV 18 were also positive by in situ hybridization and yielded a punctate signal, considered to represent the integrated form. In conclusion, p16(INK4a) was overexpressed and HPV 18 was frequently detected in an integrated form in small cell carcinoma. Therefore, inactivation of Rb protein by HPV 18 E7 protein may be associated with carcinogenesis of small cell carcinoma the same as inactivation of Rb protein by HPV 16 E7 protein is associated with carcinogenesis of squamous cell carcinoma.     

Characterization of human papillomavirus type 66 from an invasive carcinoma of the uterine cervix.

Human papillomavirus (HPV) DNA sequences coexisting with HPV16 and HPV45 were cloned from an invasive cervical carcinoma. The cloned HPV was shown to be a novel type, named HPV66, and is related to HPV56 (an HPV detected in cervical cancer). After screening 160 anogenital biopsies, four specimens exhibited histological features of intraepithelial neoplasia and contained HPV66 sequences. Of these, three were found to be associated with another HPV type.     

Association between human papillomavirus infection and cytological abnormalities during early follow-up of invasive cervical cancer

Considering the limitations of cytology for detection of residual cervical cancer after radiotherapy, the aim of this study was to evaluate the frequency and viral load of high-risk HPV in cervical and vaginal samples during the early follow-up of patients treated for invasive cervical cancer and correlate the results with cytological examination. Conventional cytology and hybrid capture test were performed on cervical and vaginal samples of 52 women with invasive cervical carcinoma 3 months after therapy. High-risk HPV was detected in 46.1% of the samples and the median and the range of the ratio relative light unit (RLU)/cutoff (CO) (estimated viral load) in positive samples was 1.71 (1-2120.03). No significant difference was observed in viral frequency and in median of the ratio RLU/CO between samples of patients at different stages (I-III) and between cervical samples, from patients treated by exclusive radiotherapy with or without chemotherapy, and vaginal samples, from patients who underwent to hysterectomy and radiotherapy with or without chemotherapy. Cytological abnormalities were more frequent significantly in samples with HPV than in samples without HPV. The viral load was also higher significantly in samples with cytological abnormalities when compared with the samples without cytological abnormalities. In conclusion, HPV detection methods may be useful during the early follow-up as a complement to conventional cytology for the diagnosis of residual cervical cancer after radiotherapy.     

Human papillomavirus infection and invasive cervical neoplasia: a study of prevalence and morphology

The prevalence of human papillomavirus (HPV) DNA sequences in 45 cervical cancer biopsies was examined with the hot-start polymerase chain reaction (PCR), employing HPV consensus primers from the L1 region. The cases comprised 38 squamous cell carcinomas, three adenosquamous carcinomas, and four adenocarcinomas. PCR products were typed with single-strand conformation polymorphism (SSCP) and the HPV types detected were correlated with tumour type. Forty-three biopsies were HPV-positive, HPV16 being the most prevalent type. HPV18/33/45/58 were also detected, but no low-risk or multiple types. Keratinizing squamous cell carcinoma was invariably associated with HPV16 and adenosquamous carcinoma and adenocarcinoma with HPVs 18/45. Non-keratinizing squamous cell carcinomas harboured all five detected types. Our data corroborate the view that malignant cervical tumours are almost invariably associated with high-risk HPV and that certain malignant cervical tumour phenotypes correlate with specific HPV types. © 1997 John Wiley & Sons, Ltd.     

Human papillomavirus type 16 integration in cervical carcinoma in situ and in invasive cervical cancer

Integration of human papillomavirus type 16 (HPV-16) into the host DNA has been proposed as a potential marker of cervical neoplastic progression. In this study, a quantitative real-time PCR (qRT-PCR) was used to examine the physical status of HPV-16 in 126 cervical carcinoma in situ and 92 invasive cervical cancers. Based on criteria applied to results from this qRT-PCR assay, HPV-16 was characterized in carcinoma in situ cases as episomal (61.9%), mixed (i.e., episomal and integrated; 29.4%), and integrated (8.7%) forms. In invasive cervical cancer samples, HPV-16 was similarly characterized as episomal (39.1%), mixed (45.7%), and integrated (15.2%) forms. The difference in the frequency of integrated or episomal status estimated for carcinoma in situ and invasive cervical cancer cases was statistically significant (P = 0.003). Extensive mapping analysis of HPV-16 E1 and E2 genes in 37 selected tumors demonstrated deletions in both E1 and E2 genes with the maximum number of losses (78.4%) observed within the HPV-16 E2 hinge region. Specifically, deletions within the E2 hinge region were detected most often between nucleotides (nt) 3243 and 3539. The capacity to detect low-frequency HPV-16 integration events was highly limited due to the common presence and abundance of HPV episomal forms. HPV-16 E2 expressed from intact episomes may act in trans to regulate integrated genome expression of E6 and E7.     

Human papillomavirus infection in non-neoplastic uterine cervical disease in Hong Kong.

The polymerase chain reaction (PCR) was used to detect and identify human papillomavirus (HPV) in 108 cases of formalin-fixed, paraffin-embedded, non-neoplastic uterine cervical biopsy tissue retrieved from the surgical pathology archives of the Department of Pathology, Caritas Medical Centre, Hong Kong. After DNA extraction, HPV L1 gene primers were used to detect the presence of HPV, and type-specific primers (to HPV types 6, 11, 16, 18, 31 and 33) were used to identify the specific HPV type on HPV L1-positive cases. PCR amplification of the beta-globin gene was used to ensure the quality of amplifiable DNA extracted. Of 94 cases that yielded sufficient good-quality DNA for PCR analysis, three (one endocervical polyp, one chronic inflammation with erosion, and a normal biopsy) had detectable HPV infection. Two of these had high-risk HPV type 16; the other had an uncommon HPV type. In view of the low incidence of HPV found in these patients, large-scale population screening of clinical samples using PCR to detect the presence of HPV and identify high-risk asymptomatic patients would not be cost-effective.     

Telomerase activation in cervical cancer.

It has been hypothesized that infection with high-risk human papillomaviruses (HPVs), in conjunction with other cellular events, plays a critical role in the development of cervical cancer. Activation of telomerase, a ribonucleoprotein enzyme complex that synthesizes telomere repeats, has been associated with acquisition of the immortal phenotype in vitro and is commonly observed in human cancers. In this study, we have examined 10 high-grade cervical cancers for telomerase activity and for the presence of HPV. Telomerase activity was detected in all of the cancers but in none of the paired histopathologically normal uterine tissues or in normal cervical epithelium. Analysis of these same tissues for HPV nucleic acids by polymerase chain reaction (PCR) using primers from the HPV L1 and E6 open reading frames demonstrated that 7 of 10 cancers were positive for HPV, 3 for HPV type 16 (HPV-16), and 4 for HPV-18. In one case, HPV-16 was detected in histopathologically normal uterine tissue, the same type as that detected in the cancer from the same patient. HPV DNA was not detected in 3 of 10 cancers. These results indicate that telomerase activation is common in high-grade cervical cancers and suggests that telomerase activity may be a useful diagnostic marker for the disease.     

The epidemiology of human papillomavirus infection and cervical cancer

Cervical cancer has been recognized as a rare outcome of a common Sexually Transmitted Infection (STI). The etiologic association is restricted to a limited number of viral types of the family of the Human Papillomaviruses (HPVs). The association is causal in nature and under optimal testing systems, HPV DNA can be identified in all specimens of invasive cervical cancer. As a consequence, it has been claimed that HPV infection is a necessary cause of cervical cancer. The evidence is consistent worldwide and implies both the Squamous Cell Carcinomas (SCC), the adenocarcinomas and the vast majority (i.e. > 95%) of the immediate precursors, namely High Grade Squamous Intraepithelial Lesions (HSIL)/Cervical Intraepithelial Neoplasia 3 (CIN3)/Carcinoma in situ. Co-factors that modify the risk among HPV DNA positive women include the use of oral contraceptives (OC) for five or more years, smoking, high parity (five or more full term pregnancies) and previous exposure to other sexually transmitted diseases such as Chlamydia Trachomatis (CT) and Herpes Simplex Virus type 2 (HSV-2). Women exposed to the Human Immunodeficiency Virus (HIV) are at high risk for HPV infection, HPV DNA persistency and progression of HPV lesions to cervical cancer.     

Distribution of human papillomavirus genotypes in cervical intraepithelial neoplasia and invasive cervical cancer in Canada

Infection with high‐risk human papillomavirus (HPV) causes cervical intraepithelial neoplasia (CIN) and invasive cervical cancer (ICC). The distribution of HPV types in cervical diseases has been previously described in small studies for Canadian women. The prevalence of 36 HPV genotypes in 873 women with CIN and 252 women with ICC was assessed on cervical exfoliated cells analyzed with the Linear Array (Roche Molecular System). HPV16 was the most common genotype in CIN and ICC. The seven most frequent genotypes in order of decreasing frequency were HPV16, 51, 52, 31, 39, 18, and 56 in women with CIN1, HPV16, 52, 31, 18, 51, 39, and 33 in women with CIN2, HPV16, 31, 18, 52, 39, 33, and 58 in women with CIN3, and HPV16, 18, 45, 33, 31, 39, and 53 in women with ICC. HPV18 was detected more frequently in adenocarcinoma than squamous cell carcinoma (P = 0.013). Adjustment for multiple type infections resulted in a lower percentage attribution in CIN of HPV types other than 16 or 18. The proportion of samples containing at least one oncogenic type was greater in CIN2 (98.4%) or CIN3 (100%) than in CIN1 (80.1%; P < 0.001 for each comparison). Multiple type infections were demonstrated in 51 (20.2%) of 252 ICC in contrast to 146 (61.3%) of 238 women with CIN3 (P < 0.001). Adjusting for multiple HPV types, HPV16 accounted for 52.1% and HPV18 for 18.1% of ICCs, for a total of 70.2%. Current HPV vaccines should protect against HPV types responsible for 70% of ICCs in Canadian women. J. Med. Virol. 83:1034–1041, 2011. © 2011 Wiley‐Liss, Inc.     

唇鳞状细胞癌患者人乳头瘤病毒感染的检测分析

目的 了解唇鳞状细胞癌患者人乳头瘤病毒感染的情况.方法 对收集到的9例临床诊断唇癌病例的石蜡组织标本应用Luminex及PCR的方法对HPV感染进行基因检测,应用免疫组织化学的方法对HPV16/18E6蛋白进行检测.结果 在9例临床诊断的唇癌病例中,通过Luminex 及PCR的方法发现1例病例具有HPV16的感染;通过免疫组织化学的方法发现7例病例具有HPV16/18的感染,总阳性率达到8/9.结论 此研究中在唇癌患者中较高的HPV感染率间接说明皮肤的直接接触对HPV感染的重要性,为阐明唇癌的发病机制提供依据.     

Method for testing for human papillomavirus infection in patients with cervical intraepithelial disease

To determine whether DNA detection of high-risk human papillomavirus could represent a reliable screening technique and a useful follow-up method, we investigated the performance of the Hybrid Capture II assay in detecting high-grade cervical lesions. The test positivity at 1.86 pg/ml had a high sensitivity (94.7%) and improved specificity. It was also a suitable follow-up method for detecting the recurrence of cervical intraepithelial disease in patients.     

Human papillomavirus genotyping by oligonucleotide microarray and p16 expression in uterine cervical intraepithelial neoplasm and in invasive carcinoma in Korean women

For evaluating the diagnostic significance of p16(INK4A) over-expression in the uterine cervical intraepithelial neoplasm and in invasive carcinoma, human papillomavirus (HPV) was detected and genotyped by oligonucleotide microarray in archival tissues of 117 cervical specimens, including 47 invasive squamous cell carcinomas (SCC), 30 cases of cervical intraepithelial neoplasia (CIN), 20 adenocarcinomas, and 20 cases of non-neoplastic cervix. The expression of p16(INK4A) protein was immunohistochemically studied in these cases and in five HPV-positive and one HPV-negative cervical cancer cell lines. HPV was detected in 50% of CIN, 61.7% of SCC, and 45.5% of adenocarcinomas. p16(INK4A) expression was seen in all 20 cases of adenocarcinoma, 78.7% (37/47) of SCC, and 96.7% (29/30) of CIN, but not in any cases of the non-neoplastic cervix. There was no difference in p16(INK4A) expression between the HPV-positive and HPV-negative cervical lesions. All HPV-positive and -negative cervical cancer cell lines expressed p16(INK4A) protein. In conclusion, the presence of p16(INK4A) expression in cervical squamous and glandular epithelium indicates the existence of dysplasia or malignancy in the uterine cervix, regardless of HPV infection.     

Prevalence and genotype distribution of cervical human papillomavirus infection in Macao

Population‐specific epidemiological data on human papillomavirus (HPV) infection are essential for formulating strategies to prevent cervical cancer. The age‐specific prevalence of HPV infection was determined among 1,600 women enrolled for cervical screening in Macao. A U‐shaped age‐specific prevalence curve with a first peak (prevalence rate, 10%) at 20–25 years and a second peak (13%) at 51–55 years was observed. Co‐infections with multiple types were detected in 32.5% of HPV‐positive subjects and without significant variation among different age groups (P = 0.318). The majority (84.6%) of the positive samples harbored high‐ or probable high‐risk HPV types, and these types also exhibited a similar U‐shaped age‐specific prevalence curve. In contrast, low and unknown‐risk HPV types remained at a low prevalence (1.5–2.5%) throughout the age groups between 20 and 50 years, and with a small peak (4.5%) at 51–55 years. HPV 52 was the most common type found in 26.8% of positive samples, followed by HPV 16 (15.5%), HPV 68 (11.4%), HPV 18 and HPV 58 (8.9% each), HPV 54 (8.1%), HPV 53 (7.3%), HPV 39 (6.5%), HPV 33 and HPV 66 (5.7% each). In conclusion, because of the early peak of infection, vaccination and educational campaigns in Macao should start early and target at teenagers. The presence of a second peak containing mainly high‐risk HPV types in older women indicates the need to evaluate the cover of the cervical screening programme for older women. Further study to determine the contribution of HPV 52 in high‐grade cervical neoplasia and invasive cancers in Macao is warranted. J. Med. Virol. 82:1724–1729, 2010. © 2010 Wiley‐Liss, Inc.     

The clearance of oral high-risk human papillomavirus infection is impaired by long-term persistence of cervical human papillomavirus infection

Persistence of high-risk (HR-) human papillomavirus (HPV) infection of the uterine cervix increases the risk of cervical cancer. Oral HPV infections are among potential covariates of long-term genotype-specific persistent cervical HR-HPV infections. It is not known whether this persistence reflects inability of the host to reject HPV infections in general. A case–control setting was designed to estimate the covariates of long-term persistent cervical HR-HPV infections using multivariate generalized estimating equation (GEE) models. HPV was detected with PCR using GP05+/GP06+-primers and genotyped for 24 HPVs with a Multimetrix-kit. The cases (n = 43) included women who had genotype-specific persistent cervical HR-HPV infection for at least 24 months (24M+) and controls were women who tested repeatedly HPV-negative in their cervical samples (n = 52). These women represent a sub-cohort of the Finnish Family HPV Study. The cases differed significantly from the HPV-negative controls in several aspects: they were younger, had a longer mean time to incident oral HPV infection (40.7 versus 23.6 months), longer duration of oral HPV persistence (38.4 versus 14.1 months), and longer time to clearance of their oral HPV infection (50.0 versus 28.2 months). In multivariate GEE analysis, the second pregnancy during the follow up was the only independent predictor with significant protective effect against 24M+ persistent cervical HR-HPV infections, OR of 0.15 (95% CI 0.07–0.34). To conclude, long-term persistent cervical HR-HPV infections are associated with a prolonged clearance of oral HR-HPV infections while new pregnancy protects against persistent cervical HR-HPV infections.     

Increased angiogenesis in the uterine cervix associated with human papillomavirus infection

We studied the relationship between angiogenesis (using the CD34 antibody), the presence of human papilloma virus (HPV) infection, HPV E6 protein expression and the accumulation of p53 protein at various phases of tumour progression in the uterine cervix. Expression of CD34, p53 and HPV E6 protein was evaluated by immunocytochemistry. Presence of the mutant p53 was detected using a mutant specific ELISA, and the type of HPV was determined by the Polymerase Chain Reaction. A total of 230 cervical tissue samples were analyzed and included 40 cases of apparently normal cervical epithelium, 37 low grade squamous intraepithelial lesions (SILs), 43 high grade SILs, 36 well-differentiated squamous cell carcinomas (DSCC), 31 moderately differentiated (MDSCC) and 43 poorly differentiated carcinomas (PDSCC). There was an excellent correlation between the extent of angiogenesis and histological abnormality (r = 0.912, p = 0.000004). The least extent of angiogenesis was seen in normal cervical tissue and low grade SILs where the mean (low power) intra lesional vascular density (ILVD) was 12 +/- 1.13 and 25.66 +/- 5.20, respectively. In high grade squamous intraepithelial lesions (SILs), the mean ILVD value was 80.84 +/- 25.57. In well-differentiated squamous cell carcinomas (WDSCC's) the mean value was 144.22 +/- 28.67 while in moderately differentiated squamous cell carcinomas (MDSCC's) the mean value was 166.29 +/- 34.95 and in poorly differentiated tumours (PDSCC's) 192.42 +/- 27.98. The extent of angiogenesis also correlated to presence of HPV (r = 0.505, p = 0.00001). Increased CD34 expression was associated with the presence of HPV types 16 and 18. A similar correlation was also evident in HPV, 16/18 infected cases expressing the E6 protein (r = 0.612, p = 0.000001). CD34 expression also correlated well with p53 accumulation (r = 0.859, p = 0.000002). Presence of HPV infection significantly correlated with the extent of histological abnormality (r = 0.467, p = 0.00001). Expression of E6 also showed this significant correlation (r = 0.644, p = 0.00002). Accumulation of p53 was significantly more elevated in HPV 16-infected lesions (r = 0.518, p = 0.00001) and E6-expressing cells (r = 0.650, p = 0.000004). Only 12 of the 230 cases analyzed showed presence of the mutant p53 protein. Angiogenesis appears to increase with histological abnormality in the uterine cervix. Angiogenesis also appears to be influenced by high risk HPV infection, the expression of the E6 transforming protein and the p53 tumour suppressor protein.