Monoclonal expansion with integration of high-risk type human papillomaviruses is an initial step for cervical carcinogenesis: association of clonal status and human papillomavirus infection with clinical outcome in cervical intraepithelial neoplasia

Inhibition of cytosine 5-hydroxymethylation during progression of cancer precursor lesions in the uterine cervix

Methylation and hydroxymethylation of cytosine moieties in CpG islands of specific genes are epigenetic processes shown to be involved in the development of cervical (pre)neoplastic lesions. We studied global (hydroxy)methylation during the subsequent steps in the carcinogenic process of the uterine cervix by using immunohistochemical protocols for the detection of 5-methylcytosine (5-mC) and 5-hydroxymethylcytosine (5-hmC) in paraffin-embedded tissues of the normal epithelia and (pre)malignant lesions. This approach allowed obtaining spatially resolved information of (epi)genetic alterations for individual cell populations in morphologically heterogeneous tissue samples. The normal ectocervical squamous epithelium showed a high degree of heterogeneity for both modifications, with a major positivity for 5-mC in the basal and parabasal layers in the ectocervical region, while 5-hmC immunostaining was even more restricted to the cells in the basal layer. Immature squamous metaplasia, characterized by expression of SOX17, surprisingly showed a decrease of 5-hmC in the basal compartments and an increase in the more superficial layers of the epithelium. The normal endocervical glandular epithelium showed a strong immunostaining reactivity for both modifications. At the squamocolumnar junctions, a specific 5-hmC pattern was observed in the squamous epithelium, resembling that of metaplasia, with the typical weak to negative reaction for 5-hmC in the basal cell compartment. The reserve cells underlying the glandular epithelium were also largely negative for 5-hmC but showed immunostaining for 5-mC. While the overall methylation status remained relatively constant, about 20% of the high-grade squamous lesions showed a very low immunostaining reactivity for 5-hmC. The (pre)malignant glandular lesions, including adenocarcinoma in situ (AIS) and adenocarcinoma showed a progressive decrease of hydroxymethylation with advancement of the lesion, resulting in cases with regions that were negative for 5-hmC immunostaining. These data indicate that inhibition of demethylation, which normally follows cytosine hydroxymethylation, is an important epigenetic switch in the development of cervical cancer.

Epidemiology of cervical cancer and HPV infection in Asia and Oceania

Cancer will continue to be a major source of morbidity and mortality globally during the foreseeable future. Human papillomavirus (HPV)-related cancer is now a serious problem in both women and men. The most common HPV-related cancer is cervical cancer in females and oropharyngeal cancer in males. Eastern Africa has a high age-standardized incidence of HPV-related cancers, followed in order by Southern Africa, Central Africa, and then the rest of Africa. Among Asian and Oceania countries, Fiji, Papua New Guinea, Solomon Islands, Indonesia, Maldives, and Myanmar have extremely high age-standardized incidences and mortality. Oropharyngeal cancer is less common than cervical cancer, but the age-standardized incidence, for both females and males, is higher in Western Europe, Northern Europe, North America, and Australia/New Zealand. Oropharyngeal cancer incidence rates differ significantly from the rates of cervical cancer within the same countries. In Asia and Oceania, the incidence of oropharyngeal cancer is particularly high among females in Bhutan, Bangladesh, and Australia, and it is highest among males in Bangladesh, New Caledonia, Australia, and French Polynesia. To a certain extent, cervical cancer can be reduced through the development of cervical screening programs and improvements in screening uptake. On the other hand, for oropharyngeal cancer, as of yet, no effective means of cancer screening has been established. Widespread uptake of HPV vaccine will contribute to the reduction of HPV-related cancers in Asia and Oceania, but also in the rest of the world.

Molecular Pap Smear: Validation of HPV Genotype and Host Methylation Profiles of ADCY8, CDH8, and ZNF582 as a Predictor of Cervical Cytopathology

Primary high-risk Human Papillomavirus (hrHPV) screening has recently become an accepted standalone or co-test with conventional cytology. Unfortunately, hrHPV singularly lacks specificity for cytopathological grade. However, mechanisms and markers of evolving virus-host interactions at the epigenome level may be harnessed as a better predictor of carcinogenesis. This study aimed to validate and expand the clinical performance of a multiparametric biomarker panel, referred to as the "Molecular Pap smear" based, on HPV genotype and ADCY8, CDH8 and ZNF582 CpG-methylation as a predictive classifier of cervical cytology. This prospective, cross-sectional study used an independent cohort of residual liquid-based cytology for HPV genotyping and epigenetic analysis. Extracted DNA underwent parallel PCR using 3 primer sets for HPV DNA amplification. HPV-infected samples were genotyped by Sanger sequencing. Promoter methylation levels of 3 tumor suppressor genes were quantified by bisulfite-pyrosequencing of genomic DNA on the newest high-resolution PyroMark Q48 platform. Logistic model performance was compared, and model parameters were used to predict and classify binary cytological outcomes. A total of 883 samples were analyzed. HPV DNA positivity correlated with worsening grade: 125/237 (53%) NILM; 136/235 (58%) ASCUS; 222/229 (97%) LSIL; and 157/182 (86%) HSIL samples. The proportion of carcinogenic HPV-types in PCR-positive sequenceable samples correlated with worsening grade: NILM 34/98 (35%); ASCUS 50/113 (44%); LSIL 92/214 (43%); HSIL 129/152 (85%). Additionally, ADCY8, CDH8, and ZNF582 methylation levels increased in direct correlation with worsening grade. Overall, the multi-marker modeling parameters predicted binarized cytological outcomes better than HPV-type alone with significantly higher area under the receiver operator curve (AUC)s, respectively: NILM vs. > NILM (AUC 0.728 vs. 0.709); NILM/ASCUS vs. LSIL/HSIL (AUC 0.805 vs. 0.776); and Collapse

Key Words

• DNA methylation
• carcinogenesis
• epigenetic modification
• evolution
• host-pathogen interactions
• human papillomavirus infection
• pap smear
• pyrosequencing

Collapse

MESH Headings Collapse

Grants Collapse

Affiliation(s)

Jane Shen-Gunther Gynecologic Oncology & Clinical Investigation, Department of Clinical Investigation, Brooke Army Medical Center, Fort Sam Houston, TX, United States Department of Molecular Medicine, Cancer Therapy and Research Center, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
Qingqing Xia Department of Clinical Investigation, Brooke Army Medical Center, Fort Sam Houston, TX, United States
Winfred Stacey Department of Clinical Investigation, Brooke Army Medical Center, Fort Sam Houston, TX, United States
Heisy B. Asusta Department of Obstetrics and Gynecology, Brooke Army Medical Center, Fort Sam Houston, TX, United States

Collapse

Minimum error calibration and normalization for genomic copy number analysis

BACKGROUND

Copy number variations (CNV) are regional deviations from the normal autosomal bi-allelic DNA content. While germline CNVs are a major contributor to genomic syndromes and inherited diseases, the majority of cancers accumulate extensive "somatic" CNV (sCNV or CNA) during the process of oncogenetic transformation and progression. While specific sCNV have closely been associated with tumorigenesis, intriguingly many neoplasias exhibit recurrent sCNV patterns beyond the involvement of a few cancer driver genes. Currently, CNV profiles of tumor samples are generated using genomic micro-arrays or high-throughput DNA sequencing. Regardless of the underlying technology, genomic copy number data is derived from the relative assessment and integration of multiple signals, with the data generation process being prone to contamination from several sources. Estimated copy number values have no absolute or strictly linear correlation to their corresponding DNA levels, and the extent of deviation differs between sample profiles, which poses a great challenge for data integration and comparison in large scale genome analysis.

RESULTS

In this study, we present a novel method named "Minimum Error Calibration and Normalization for Copy Numbers Analysis" (Mecan4CNA). It only requires CNV segmentation files as input, is platform independent, and has a high performance with limited hardware requirements. For a given multi-sample copy number dataset, Mecan4CNA can batch-normalize all samples to the corresponding true copy number levels of the main tumor clones. Experiments of Mecan4CNA on simulated data showed an overall accuracy of 93% and 91% in determining the normal level and single copy alteration (i.e. duplication or loss of one allele), respectively. Comparison of estimated normal levels and single copy alternations with existing methods and karyotyping data on the NCI-60 tumor cell line produced coherent results. To estimate the method's impact on downstream analyses, we performed GISTIC analyses on the original and Mecan4CNA normalized data from the Cancer Genome Atlas (TCGA) where the normalized data showed prominent improvements of both sensitivity and specificity in detecting focal regions.

CONCLUSIONS

Mecan4CNA provides an advanced method for CNA data normalization, especially in meta-analyses involving large profile numbers and heterogeneous source data quality. With its informative output and visualization options, Mecan4CNA also can improve the interpretation of individual CNA profiles. Mecan4CNA is freely available as a Python package and through its code repository on Github.

Wnt signaling in cervical cancer?

Cervical cancer (CC) is the second most common malignant cancer in women. CC is difficult to diagnose, has a high recurrence rate, and is resistant to systemic therapies; as a result, CC patients have a relatively poor prognosis. One potential link to CC is the Wnt signaling pathway and its downstream effectors, which regulate cell differentiation, proliferation, migration, and fate. The aberrant activation of Wnt signaling is associated with various cancers, including CC. Recent studies have shown that activating or inhibiting the intracellular signal transduction in this pathway can regulate cancer cell growth and viability. This review will summarize the experimental evidence supporting the significance of the Wnt signaling pathway in CC, and will also discuss the current clinical role of Wnt signaling in CC diagnosis, therapy, and prognosis.

Clinical course of untreated cervical intraepithelial neoplasia grade 2 under active surveillance: systematic review and meta-analysis

OBJECTIVE

To estimate the regression, persistence, and progression of untreated cervical intraepithelial neoplasia grade 2 (CIN2) lesions managed conservatively as well as compliance with follow-up protocols.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

Medline, Embase, and the Cumulative Index to Nursing and Allied Health Literature (CINAHL) from 1 January 1973 to 20 August 2016.

ELIGIBILITY CRITERIA

Studies reporting on outcomes of histologically confirmed CIN2 in non-pregnant women, managed conservatively for three or more months.

DATA SYNTHESIS

Two reviewers extracted data and assessed risk of bias. Random effects model was used to calculate pooled proportions for each outcome, and heterogeneity was assessed using I² statistics.

MAIN OUTCOME MEASURES

Rates of regression, persistence, or progression of CIN2 and default rates at different follow-up time points (3, 6, 12, 24, 36, and 60 months).

RESULTS

36 studies that included 3160 women were identified (seven randomised trials, 16 prospective cohorts, and 13 retrospective cohorts; 50% of the studies were at low risk of bias). At 24 months, the pooled rates were 50% (11 studies, 819/1470 women, 95% confidence interval 43% to 57%; I²=77%) for regression, 32% (eight studies, 334/1257 women, 23% to 42%; I²=82%) for persistence, and 18% (nine studies, 282/1445 women, 11% to 27%; I²=90%) for progression. In a subgroup analysis including 1069 women aged less than 30 years, the rates were 60% (four studies, 638/1069 women, 57% to 63%; I²=0%), 23% (two studies, 226/938 women, 20% to 26%; I²=97%), and 11% (three studies, 163/1033 women, 5% to 19%; I²=67%), respectively. The rate of non-compliance (at six to 24 months of follow-up) in prospective studies was around 10%.

CONCLUSIONS

Most CIN2 lesions, particularly in young women (<30 years), regress spontaneously. Active surveillance, rather than immediate intervention, is therefore justified, especially among young women who are likely to adhere to monitoring.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO 2014: CRD42014014406.

HPV Testing and Pap Test: Role for a Combined Approach in a Non-Screened Population

The aim of the present study was to test the polymerase chain reaction (PCR) as a tool to identify human papillomavirus (HPV) in routine cytological samples scraped from the uterine cervix. Moreover, attention has been focused on the correlation between HPV types and early intraepithelial lesions. The study involved 586 women who had undergone conventional Pap test. Analysis of HPV infection was performed by PCR and HPV typing by dot blot. In a group of 78 cases histologically diagnosed as high-grade squamous intraepithelial lesions (HSILs), the cytological diagnosis was correct in 92.3% and the HPV test was positive in 89.8% of cases; combined positivity at Pap and/or HPV tests raised this figure to 99.0%. In a group of 67 cases histologically diagnosed as low-grade squamous intraepithelial lesions (LSILs), the cytological diagnosis was correct in 73.1% and the PCR-based HPV test was positive in 64.2%; combined positivity at Pap and/or HPV tests raised this figure to 91.0%. This study confirms the limitations of screening programs based on Pap test only. Our results suggest, in fact, that adding the HPV test to primary screening could increase the yield of preinvasive cervical lesions.

Deep sequencing of HPV E6/E7 genes reveals loss of genotypic diversity and gain of clonal dominance in high-grade intraepithelial lesions of the cervix

BACKGROUND

Human papillomavirus (HPV) is the carcinogen of almost all invasive cervical cancer and a major cause of oral and other anogenital malignancies. HPV genotyping by dideoxy (Sanger) sequencing is currently the reference method of choice for clinical diagnostics. However, for samples with multiple HPV infections, genotype identification is singular and occasionally imprecise or indeterminable due to overlapping chromatograms. Our aim was to explore and compare HPV metagenomes in abnormal cervical cytology by deep sequencing for correlation with disease states.

RESULTS

Low- and high-grade intraepithelial lesion (LSIL and HSIL) cytology samples were DNA extracted for PCR-amplification of the HPV E6/E7 genes. HPV+ samples were sequenced by dideoxy and deep methods. Deep sequencing revealed ~60% of all samples (n = 72) were multi-HPV infected. Among LSIL samples (n = 43), 27 different genotypes were found. The 3 dominant (most abundant) genotypes were: HPV-39, 11/43 (26%); -16, 9/43 (21%); and -35, 4/43 (9%). Among HSIL (n = 29), 17 HPV genotypes were identified; the 3 dominant genotypes were: HPV-16, 21/29 (72%); -35, 4/29 (14%); and -39, 3/29 (10%). Phylogenetically, type-specific E6/E7 genetic distances correlated with carcinogenic potential. Species diversity analysis between LSIL and HSIL revealed loss of HPV diversity and domination by HPV-16 in HSIL samples.

CONCLUSIONS

Deep sequencing resolves HPV genotype composition within multi-infected cervical cytology. Biodiversity analysis reveals loss of diversity and gain of dominance by carcinogenic genotypes in high-grade cytology. Metagenomic profiles may therefore serve as a biomarker of disease severity and a population surveillance tool for emerging genotypes.

Human Papillomavirus Laboratory Testing: the Changing Paradigm

High-risk human papillomaviruses (HPVs) cause essentially all cervical cancers, most anal and oropharyngeal cancers, and some vaginal, vulvar, and penile cancers. Improved understanding of the pathogenesis of infection and the availability of newer tests are changing the approach to screening and diagnosis. Molecular tests to detect DNA from the most common high-risk HPVs are FDA approved for use in conjunction with cytology in cervical cancer screening programs. More-specific tests that detect RNA from high-risk HPV types are now also available. The use of molecular tests as the primary screening tests is being adopted in some areas. Genotyping to identify HPV16 and -18 has a recommended role in triaging patients for colposcopy who are high-risk HPV positive but have normal cytology. There are currently no recommended screening methods for anal, vulvar, vaginal, penile, or oropharyngeal HPV infections. HPV testing has limited utility in patients at high risk for anal cancer, but p16 immunohistochemistry is recommended to clarify lesions in tissue biopsy specimens that show moderate dysplasia or precancer mimics. HPV testing is recommended for oropharyngeal squamous cell tumors as a prognostic indicator. Ongoing research will help to improve the content of future guidelines for screening and diagnostic testing.

Clinical outcomes of abnormal cervical cytology and human papillomavirus-related lesions in patients with organ transplantation: 11-year experience at a single institution

OBJECTIVES

The objective of this study is to analyze the clinical outcomes of abnormal cervical cytology and newly diagnosed human papillomavirus (HPV)-related disease after organ transplantation.

MATERIALS AND METHODS

Medical records from July 2004 to August 2015 were reviewed, and thirteen patients were identified who had been newly diagnosed with HPV-related disease (cervical intraepithelial neoplasia [CIN] and cervical cancer) after organ transplantation. The median transition time to the aggravation of cervical cytology and the spontaneous regression rate of CIN were evaluated. Clinical outcomes of CIN1 and CIN2 were compared between the general population and patients with organ transplantation. We also reviewed the current literature regarding the incidence of HPV infection, Pap smear abnormality and/or CIN after organ transplantation.

RESULTS

The cervical cytology aggravated in nine of the 13 patients (69 %). In seven of the 13 cases (54 %), treatments such as cervical conization, laser vaporization, or radiation therapy, were conducted. HPV-related disease disappeared after treatment in only three of the seven actively treated cases (43 %). In contrast, the lesions persisted in three (43 %) cases after treatment. One patient died from cervical cancer. The spontaneous regression rate of the HPV-related diseases, if left untreated, was 0 %. There was a statistically significant difference in the clinical outcomes of CIN1 and CIN2 between the general population and patients with organ transplantation (p = 0.0026 and 0.0315, respectively; chi-squared test).

CONCLUSIONS

HPV-related lesions that are newly diagnosed after organ transplantation do not seem to regress as spontaneously as in the general population. Physicians should recognize the importance of close monitoring and long-term follow-up.

Progression of naive intraepithelial neoplasia genome to aggressive squamous cell carcinoma genome of uterine cervix

Although cervical intraepithelial neoplasia (CIN) is considered a neoplasia, its genomic alterations remain unknown. For this, we performed whole-exome sequencing and copy number profiling of three CINs, a microinvasive carcinoma (MIC) and four cervical squamous cell carcinomas (CSCC). Both total mutation and driver mutation numbers of the CINs were significantly fewer than those of the MIC/CSCCs (P = 0.036 and P = 0.018, respectively). Importantly, PIK3CA was altered in all MIC/CSCCs by either mutation or amplification, but not in CINs. The CINs harbored significantly lower numbers of copy number alterations (CNAs) than the MIC/CSCCs as well (P = 0.036). Pathway analysis predicted that the MIC/CSCCs were enriched with cancer-related signalings such as cell adhesion, mTOR signaling pathway and cell migration that were depleted in the CINs. The mutation-based estimation of evolutionary ages identified that CIN genomes were younger than MIC/CSCC genomes. The data indicate that CIN genomes harbor unfixed mutations in addition to human papilloma virus infection but require additional driver hits such as PIK3CA, TP53, STK11 and MAPK1 mutations for CSCC progression. Taken together, our data may explain the long latency from CIN to CSCC progression and provide useful information for molecular diagnosis of CIN and CSCC.

Co-existing of adenoid cystic carcinoma and invasive squamous cell carcinoma of the uterine cervix: a report of 3 cases with immunohistochemical study and evaluation of human papillomavirus status

Backgrounds

The aim of this study was to describe the clinicopathological characteristics and high-risk human papillomavirus (HPV) infection status in patients diagnosed with co-existing of adenoid cystic carcinoma (ACC) and invasive squamous cell carcinoma (SCC) of the uterine cervix.

Methods

Three patients were identified from the pathology databank of Peking Union Medical College Hospital from year 2000 to 2014. Immunohistochemistry and in situ hybridization (ISH) were employed in this study.

Results

The patients were aged 64, 77 and 63 years (average, 68 years old). All the patients were postmenopausal women who presented with bloody or watery vaginal discharge. The cervical cytology screening results were all suspicious for high-grade squamous intraepithelial lesion (HSIL). The subsequent cervical colposcopy biopsies all showed cervical intraepithelial neoplasia III (CINIII). One patient received only a cervical conization, whereas the other two patients underwent hysterectomy. The immunohistochemical results showed that the ACC compartments were positive for CK7 and CD117; the cases of SCC were negative for CK7 and CD117. P63 staining was strongly positive and diffuse throughout the SCC compartments, whereas only patchy positive areas were observed in the ACC. MYB exhibited strong nuclear staining in the ACC and SCC compartments but negative staining in the endocervical gland. In situ hybridization (ISH) signals for high-risk HPV DNA and mRNA were present in the two compartments of all three patients. The patients had no evidence of disease at an average follow-up time of 21.6 months.

Conclusion

High-risk HPV was present in both the ACC and SCC compartments in all three patients.

Assessment of the HPV DNA methylation status in cervical lesions

The genomes of the human papillomaviruses HPV-16 and HPV-18 undergo increased CpG methylation during the progression of cervical neoplasia, possibly in response to increased recombination between viral and cellular DNA in high-grade lesions. This behavior makes HPV DNA methylation a useful biomarker of carcinogenic progression of HPV infections. The first step in detecting DNA methylation involves modification by bisulfite, which converts cytosine residues into uracil, but leaves 5-methylcytosine residues unaffected. A combination of this reaction with PCR and DNA sequencing permits to evaluate the methylation status of the sample DNA. This chapter describes the basic protocol to measure HPV-16 and HPV-18 CpG methylation by direct sequencing of the PCR products and discusses the value of modified strategies including DNA cloning, amplification with methylation-specific primers, and real-time PCR with TaqMan probes.

Gene expression changes in progression of cervical neoplasia revealed by microarray analysis of cervical neoplastic keratinocytes

To evaluate the gene expression changes involved in neoplastic progression of cervical intraepithelial neoplasia. Using microarray analysis, large-scale gene expression profile was carried out on HPV16-CIN2, HPV16-CIN3, and normal cervical keratinocytes derived from two HPV16-CIN2, two HPV-CIN3 lesions, and two corresponding normal cervical tissues, respectively. Differentially expressed genes were analyzed in normal cervical keratinocytes compared with HPV16-CIN2 keratinocytes and in HPV16-CIN2 keratinocytes compared with HPV16-CIN3 keratinocytes; 37 candidate genes with continuously increasing or decreasing expression during CIN progression were identified. One of these genes, phosphoglycerate dehydrogenase, was chosen for further characterization. Quantitative reverse transcription-polymerase chain reaction and immunohistochemical analysis confirmed that expression of phosphoglycerate dehydrogenase consistently increases during progression of CIN toward cancer. Gene expression changes occurring during CIN progression were investigated using microarray analysis, for the first time, in CIN2 and CIN3 keratinocytes naturally infected with HPV16. Phosphoglycerate dehydrogenase is likely to be associated with tumorigenesis and may be a potential prognostic marker for CIN progression.

Specific type epigenetic changes in cervical cancers

Cancer is a genetic and epigenetic disease. Multiple genetic and epigenetic changes have been studied in cervical cancer; however, such changes are selected for during tumorigenesis and tumor aggression is not yet clear. Cervical cancer is a multistep process with accumulation of genetic and epigenetic alterations in regulatory genes, leading to activation of oncogenes and inactivation or loss of tumor suppressor genes. In cervical cancer, epigenetic alterations can affect the expression of papillomaviral as well as host genes in relation to stages representing the multistep process of carcinogenesis.

Multiple intraepithelial neoplasias of the lower female genital tract: the reliability of HPV mRNA test

OBJECTIVE

Human papillomavirus (HPV) is the most important pathogenetic factor of intraepithelial neoplasias of the lower genital tract. HPV-DNA and mRNA tests are applied for the management of epithelial dysplasias. The aims of this multicentric retrospective study were to compare the 2 molecular tests before the onset of metachronous intraepithelial lesions and to analyze the different characteristics between synchronous and metachronous lesions and their relationship to the pathologic mechanisms.

MATERIALS AND METHODS

The study concerns 55 cases of multiple intraepithelial neoplasias of the lower genital tract. Clinical features of patients with synchronous and metachronous lesions were analyzed. During a 3-year follow-up, HPV-DNA and mRNA tests were performed every 6 months after treatment of the initial lesion. HPV-DNA and mRNA results were analyzed 12 and 6 months before, at time of the onset of the metachronous lesion, and 6 months after its treatment.

RESULTS

We observed 31 synchronous lesions and 24 metachronous lesions. Immunodeficiency and multiple genotypes were associated with the synchronous lesions (p = .04 and p = .02, respectively). During the follow-up, positive DNA and mRNA tests increased before the appearance of the metachronous lesion and decreased 6 months after; mRNA test was significantly better than the DNA test 6 months before the appearance of the lesion (p = .04) and at the time of its appearance (p = .02).

CONCLUSIONS

Our results support the hypothesis that a positive HPV-mRNA test could be a marker of persistent infection and a risk factor for the onset of metachronous lesions.

Serum one-carbon metabolites and risk of cervical cancer

Most cases of cervical cancer are associated with human papilloma virus (HPV) infection of high risk types. In folate deficiency, heterogeneous nuclear ribonucleoprotein E1 (hnRNP-E1) interferes with HPV16 viral capsid protein synthesis. We aimed to study the importance of 1-carbon metabolism in cervical carcinogenesis by examining serum vitamin B12 (cobalamin), homocysteine, folate levels, and the RNA and protein expression of HPV16 L1, L2, E6, E7, and to correlate them with hnRNP-E1 expression and HPV infection in normals, squamous intraepithelial lesions (SILs), and cervical cancer subjects. Serum cobalamin, folate, and homocysteine were estimated using kits, RNA by real time PCR and proteins by Western blotting. We observed that lower folate and vitamin B12 levels were associated with HPV infection. hnRNP-E1 progressively decreased from normals (100%) to SILs (75%) to cervical cancer (52.6%). The findings show that HPV16 E6 and E7 are overexpresed whereas HPV16 L1 and L2 are downregulated at mRNA and protein levels in cervical cancer as compared to normals and SILs. The results indicate that perhaps the reduced expression of hnRNP-E1 might be involved with the cervical cancer pathogenesis, with folate playing a role in the natural history of HPV infection.

Methylation of human papillomavirus 16, 18, 31, and 45 L2 and L1 genes and the cellular DAPK gene: Considerations for use as biomarkers of the progression of cervical neoplasia

During progression of cervical cancer, human papillomavirus genomes and cellular tumor suppressor genes can become methylated. Toward a better understanding of these biomarkers, we studied 104 samples with HPV16, 18, 31, and 45 representing five pathological categories from asymptomatic infection to cancer. We grouped all samples by HPV type and pathology and measured the overall methylation of informative amplicons of HPV late genes and the cellular DAPK gene. Methylation of all four HPV types as well as of the DAPK gene is lowest in asymptomatic infection and increases successively in all four pathological categories during progression to cancer. 27 out of 28 cancer samples showed methylation both in the L2/L1 genes as well as in DAPK, but a much lower fraction in all other pathological categories. We discuss the problem to develop diagnostic tests based on complex methylation patterns that make it difficult to classify amplicons as "methylated" or "unmethylated".

Molecular targets of HPV oncoproteins: potential biomarkers for cervical carcinogenesis

Cervical cancer is the second most common cancer among women worldwide and is responsible for 275,000 deaths each year. Persistent infection with high-risk human papillomavirus (HR-HPV) is an essential factor for the development of cervical cancer. Although the process is not fully understood, molecular mechanisms caused by HPV infection are necessary for its development and reveal a large number of potential biomarkers for diagnosis and prognosis. These molecules are host genes and/or proteins, and cellular microRNAs involved in cell cycle regulation that result from disturbed expression of HR-HPV E5, E6 and E7 oncoproteins. One of the current challenges in medicine is to discover potent biomarkers that can correctly diagnose cervical premalignant lesions and standardize clinical management. Currently, studies are showing that some of these molecules are potential biomarkers of cervical carcinogenesis, and it is possible to carry out a more accurate diagnosis and provide more appropriate follow-up treatment for women with cervical dysplasia. In this paper, we review recent research studies on cell cycle molecules deregulated by HPV infections, as well as their potential use for cervical cancer screening.

Human papillomavirus infections: warts or cancer?

Human papillomaviruses (HPVs) are prevalent pathogens of mucosal and cutaneous epithelia. Productive infections of squamous epithelia lead to benign hyperproliferative warts, condylomata, or papillomas. Persistent infections of the anogenital mucosa by high-risk HPV genotypes 16 and 18 and closely related types can infrequently progress to high-grade intraepithelial neoplasias, carcinomas-in-situ, and invasive cancers in women and men. HPV-16 is also associated with a fraction of head and neck cancers. We discuss the interactions of the mucosotropic HPVs with the host regulatory proteins and pathways that lead to benign coexistence and enable HPV DNA amplification or, alternatively, to cancers that no longer support viral production.

Identification of the deleted in split hand/split foot 1 protein as a novel biomarker for human cervical cancer

The morphological detection of early neoplastic transformation leading to cervical cancer remains problematic. In this work, we have identified deleted in split hand/split foot 1 protein (DSS1) as an early biomarker that is specifically upregulated in premalignant and malignant cervical epithelial cells, but is low or undetectable in non-malignant cells. DSS1 mRNA and protein levels are significantly increased in cultured human cervical carcinoma cell lines originating from primary and metastatic tumors. In fact, > 96% of patient tumor tissues were found to have cells with elevated DSS1 when compared with tumor-adjacent normal cells. In histological sections of cervical tissue containing either invasive cervical carcinoma or its precursor lesions, DSS1 was readily detected in the tumor cells. Steady-state DSS1 expression by immortalized cervical cancer cell lines was found to be necessary for maintenance of their transformed phenotype, since stable shRNA-mediated depletion of DSS1 in HeLa cells inhibited their proliferation and colony-forming activity in monolayer cultures and prevented division of these cells in soft agar. When DSS1 levels are reduced using shRNA, the cells ultimately undergo apoptosis via activation of p53 and the p53 downstream targets, and cleavage of apoptosis-associated proteins including CPP32/caspase-3, poly(ADP-ribose)polymerase and DNA-PKcs. In addition, silencing of DSS1 makes cervical cancer cells sensitive to cell death after treatment with cisplatin. We conclude that the DSS1 protein is critically involved in the maintenance of the transformed phenotype in cervical cancer cells, and that it might be a specific, robust and reliable marker for early detection, diagnosis and treatment.

Differential DNA copy number aberrations in the progression of cervical lesions to invasive cervical carcinoma

Host genomic alterations in addition to human papillomavirus (HPV) are needed for cervical precursor lesions to progress to invasive cancer because only a small percentage of women infected by the virus develop disease. However, the genomic alterations during the progression of cervical lesions have not been systematically examined. The aim of this study was to identify differential genomic alterations among cervical intraepithelial neoplasia CIN1, CIN2, CIN3 and cervical squamous cell carcinoma (SCC). Genomic alterations were examined for 15 cases each of CIN1, CIN2, CIN3 and SCC by array-based comparative genomic hybridization (array CGH). The chromosomal regions showing significant differential in DNA copy number aberrations (DCNAs) among CIN1, CIN2, CIN3 and SCC were successfully identified by resampling-based t-test. The chromosomal regions of 5q35.3 and 2q14.3 showed significant DCNAs between CIN1 and CIN2, and between CIN2 and CIN3, respectively, while a significant difference in DCNAs between CIN3 and SCC was observed at 1q24.3, 3p14.1, 3p14.2, 5q13.2, 7p15.3, 7q22.1 and 13q32.3. In addition, the status of DCNAs in 1q43, 2p11.2, 6p11.2, 7p21.1, 7p14.3, 10q24.1, 13q22.3, 13q34 and 16p13.3 was conserved throughout the progression of CIN to SCC. The presence of differential and common DCNAs among CIN1, CIN2, CIN3 and SCC supports that the CIN progression may include continual clonal selection and evolution. This approach also identified 34 probe sets consistently overexpressed when amplified, suggesting an unbiased identification of candidate genes in SCC during cervical cancer progression.

DNA methylation changes in cervical cancers

Cervical carcinoma is one of the major causes of death in women worldwide. It is difficult to foresee a dramatic increase in cure rate even with the most optimal combination of cytotoxic drugs, surgery, and radiation; therefore, testing of molecular targeted therapies against this malignancy is highly desirable. Cervical cancer is a multistep process with accumulation of genetic and epigenetic alterations in regulatory genes, leading to activation of oncogenes and inactivation or loss of tumor suppressor genes (TSGs). In the last decade, in addition to genetic alterations, epigenetic inactivation of TSGs by promoter hypermethylation has been recognized as an important and alternative mechanism in tumorigenesis. In cervical cancer, epigenetic alterations can affect the expression of papillomavirus as well as host genes in relation to stages representing the multistep process of carcinogenesis. Here we discuss these epigenetic alterations in cervical cancer focusing on DNA methylation.

Intra-tumour genetic heterogeneity and poor chemoradiotherapy response in cervical cancer

BACKGROUND

Intra-tumour genetic heterogeneity has been reported in both leukaemias and solid tumours and is implicated in the development of drug resistance in CML and AML. The role of genetic heterogeneity in drug response in solid tumours is unknown.

METHODS

To investigate intra-tumour genetic heterogeneity and chemoradiation response in advanced cervical cancer, we analysed 10 cases treated on the CTCR-CE01 clinical study. Core biopsies for molecular profiling were taken from four quadrants of the cervix pre-treatment, and weeks 2 and 5 of treatment. Biopsies were scored for cellularity and profiled using Agilent 180k human whole genome CGH arrays. We compared genomic profiles from 69 cores from 10 patients to test for genetic heterogeneity and treatment effects at weeks 0, 2 and 5 of treatment.

RESULTS

Three patients had two or more distinct genetic subpopulations pre-treatment. Subpopulations within each tumour showed differential responses to chemoradiotherapy. In two cases, there was selection for a single intrinsically resistant subpopulation that persisted at detectable levels after 5 weeks of chemoradiotherapy. Phylogenetic analysis reconstructed the order in which genomic rearrangements occurred in the carcinogenesis of these tumours and confirmed gain of 3q and loss of 11q as early events in cervical cancer progression.

CONCLUSION

Selection effects from chemoradiotherapy cause dynamic changes in genetic subpopulations in advanced cervical cancers, which may explain disease persistence and subsequent relapse. Significant genetic heterogeneity in advanced cervical cancers may therefore be predictive of poor outcome.

Two distinct pathways to development of squamous cell carcinoma of the vulva

Squamous cell carcinoma (SCC) accounts for approximately 95% of the malignant tumors of the vaginal vulva and is mostly found in elderly women. The future numbers of patients with vulvar SCC is expected to rise, mainly because of the proportional increase in the average age of the general population. Two different pathways for vulvar SCC have been put forth. The first pathway is triggered by infection with a high-risk-type Human Papillomavirus (HPV). Integration of the HPV DNA into the host genome leads to the development of a typical vulvar intraepithelial neoplasia (VIN), accompanied with overexpression of p14^ARF and p16^INK4A. This lesion subsequently forms a warty- or basaloid-type SCC. The HPV vaccine is a promising new tool for prevention of this HPV related SCC of the vulva. The second pathway is HPV-independent. Keratinizing SCC develops within a background of lichen sclerosus (LS) through a differentiated VIN. It has a different set of genetic alterations than those in the first pathway, including p53 mutations, allelic imbalances (AI), and microsatellite instability (MSI). Further clinical and basic research is still required to understand and prevent vulvar SCC. Capsule. Two pathway for pathogenesis of squamous cell carcinoma of the value are reviewed.

Recombination of human papillomavirus-16 and host DNA in exfoliated cervical cells: a pilot study of L1 gene methylation and chromosomal integration as biomarkers of carcinogenic progression

Human papillomavirus-16 DNA replicates in productive infections in circular form, but is found in most carcinomas integrated into the host cell DNA. Because this transition is essential for carcinogenesis, detailed research is desirable and may help to triage patients with abnormal Pap smears. Previous studies addressed the chromosomal integration of HPV-16 DNA in biopsies of tumors by an indirect biomarker, methylation of the viral L1 gene and by reverse ligation polymerase chain reaction (rliPCR). The pilot study reported here asked whether these techniques can be targeted successfully at DNA prepared from exfoliated cervical cells. Abnormal Pap smears of 21 patients that were positive for HPV-16 were analyzed for (i and ii) methylation of the L1 gene after bisulfite modification and PCR amplification by direct sequencing and indirectly in cloned DNA and (iii) recombination with chromosomal DNA by rliPCR. Four of these 21 patients contained highly methylated L1 DNA, which was integrated in three of the samples with sufficient DNA for rliPCR analysis. Seven patients contained sporadically methylated L1 DNA, which was integrated in two and episomal in three samples with sufficient DNA. Ten patients contained only unmethylated DNA, which was episomal in six but possibly integrated in two samples. It is concluded that HPV-16 is found integrated chromosomally in a fraction of precancerous infections, and with higher frequency in methylated than in low or unmethylated samples. Since L1 gene methylation indicates integration, it has the potential to be used as a clinical marker of cancer progression.

The role of viral and bacterial pathogens in gastrointestinal cancer

The association of Helicobacter pylori (H. pylori) with gastric cancer is thus far the best understood model to comprehend the causal relationship between a microbial pathogen and cancer in the human gastrointestinal tract. Besides H. pylori, a variety of other pathogens are now being recognized as potential carcinogens in different settings of human cancer. In this context, viral causes of human cancers are central to the issue since these account for 10-20% of cancers worldwide. In the case of H. pylori and gastric cancer, as well as the human papillomavirus and anal cancer, the causal relationship between the infectious agent and the related cancer in the gastrointestinal tract has been clearly confirmed by epidemiological and experimental studies. Similarly, Epstein-Barr virus and the oncogenic JC virus are being suggested as possible causative agents for cancers in the upper and lower gastrointestinal tract. This review discusses various viral and microbial pathogens and their oncogenic properties in the evolution of gastrointestinal carcinogenesis and summarizes the available experimental data make a convincing agreement favoring the associations between infectious agents and specific human cancers.

Second hit in cervical carcinogenesis process: involvement of wnt/beta catenin pathway

The Human papillomavirus plays an important role in the initiation and progression of cervical cancer. However, it is a necessary but not sufficient cause to develop invasive carcinoma; hence, other factors are required in the pathogenesis of this malignancy. In this review we explore the hypothesis of the deregulation of wnt/beta-catenin signaling pathway as a "second hit" required to develop cervical cancer.

Human papillomavirus: molecular and cytologic/histologic aspects related to cervical intraepithelial neoplasia and carcinoma

Cervical cancer is unique among human cancers because it was the first cancer discovered to be virtually solely attributable to the effects of an infectious agent. Numerous epidemiologic and laboratory studies have confirmed a strong causal association between human papillomavirus infection and the development of premalignant and malignant lesions of the uterine cervix, and human papillomavirus-mediated malignant transformation is an ideal model system for the study of virally mediated carcinogenesis. Neoplastic transformation of affected cervical epithelium appears to be a direct consequence of the unregulated overexpression of viral oncoproteins that have central roles in the normal viral replicative cycle. This review is focused on the mechanisms that regulate the normal papillomavirus life cycle and on the mechanisms that appear to have central roles in malignant transformation of the cervical mucosa.

Down-regulation of insulin-like growth factor binding protein-5 (IGFBP-5): novel marker for cervical carcinogenesis

To better understand the underlying pathways of cervical carcinogenesis, cDNA microarray analysis was performed on 2 sets of squamous cell carcinomas (SCCs) and their adjacent normal squamous epithelia. Consistently altered expression was detected for 32 genes. Real-time RT-PCR analysis was conducted on a selected subset of these genes (S100A2, GPC4, p72, IGFBP-5, TRIM2 and NAB2) for 14 additional SCCs and 10 normal epithelia. This found that, of the 6 candidate genes, only the insulin-like growth factor binding protein-5 (IGFBP-5) mRNA was generally and significantly under-expressed in SCCs (p < 0.001). All normal cervical epithelia (30 of 30) stained positively for IGFBP-5 protein, with 70% showing strong staining, whereas 65% (17/26) of SCC had complete loss of IGFBP-5, and only 8% (2/26) SCC retained strong expression (p < 0.001). Immunohistochemistry of premalignant cervical intraepithelial neoplasia (CIN) lesions shows a significantly weaker or negative staining in advanced CIN3 lesions compared with normal squamous epithelia (p = 0.001). This is the first study to show that down-regulation of IGFBP-5 protein correlates with cervical carcinogenesis and does so at a preneoplastic stage.

Clonality Analysis and Human Papillomavirus Infection in Squamous Metaplasia and Atypical Immature Metaplasia of Uterine Cervix

Atypical immature squamous metaplasia (ISM) of the uterine cervix often has histological features that overlap with the histological characteristics of high-grade cervical intraepithelial neoplasia. To identify the cellular basis and clinical significance of atypical immature metaplasia (AIM), 10 cases of AIM were analyzed for the clonal status, and the presence of human papillomavirus (HPV) infection. The physical status of HPV was also evaluated in HPV type 16 (HPV-16)-positive cases. Squamous metaplasias with no nuclear atypia (29 mature squamous metaplasias [SMs]) and a single case of ISM were analyzed as a control. Nine AIMs, 20 SMs, and a single case of ISM were informative for clonal analysis. Monoclonal composition of the lesion was demonstrated in 8 (89%) of 9 AIMs, but only in 2 (10%) of 21 cases of SM without atypia (AIM vs SM + ISM, 8/9 vs 2/21; P < 0.0001). High-risk HPV was detected in 6 (60%) of 10 AIMs, all were HPV-16, but only in 3 (13%) of 24 SMs with no atypia (2/23 SM and 1/1 ISM). The frequency of high-risk HPV infection was also significant between AIMs and SM with no atypia (6/10 vs 3/24; P < 0.001). Among the cases, which were informative for clonal analysis, all 5 AIMs positive for high-risk HPV were monoclonal in composition. Physical status of HPV was examined in HPV-16-positive cases. Human papillomavirus type 16 was present as a mixture of episomal form and integrated form in 4 of 6 AIMs. These observations imply that unlike SMs with no atypia, which arises as a result of reactive or inflammatory process, lesions with the histological characteristics of AIM may be indeed true precursors of cervical carcinoma.

Distribution and viral load of eight oncogenic types of human papillomavirus (HPV) and HPV 16 integration status in cervical intraepithelial neoplasia and carcinoma

Current human papillomavirus (HPV) DNA testing using pooled probes, although sensitive, lacks specificity in predicting the risk of high-grade cervical intraepithelial neoplasia (CIN 2/3) progression. To evaluate selected HPV genotyping, viral load, and viral integration status as potential predictive markers for CIN progression, we performed HPV genotyping in formalin-fixed, paraffin-embedded cervical tissue with cervical carcinoma (29 cases) and CINs (CIN 1, 27 cases; CIN 2, 28 cases; CIN 3, 33 cases). General HPVs were screened using consensus primers GP5+/GP6+ and PGMY09/11. HPV genotyping and viral load measurement were performed using quantitative real-time PCR for eight oncogenic HPV types (16, 18, 31, 33, 35, 45, 52, and 58). HPV 16 viral integration status was evaluated by measuring HPV 16 E2/E6 ratio. We observed that HPV DNA positivity increased in parallel with the severity of CINs and carcinoma, with 59% positivity in CIN 1, 68% in CIN 2, 76% in CIN 3, and 97% in carcinoma (P trend=0.004). The eight oncogenic HPV types were significantly associated with CIN 2/3 (81%) and carcinoma (93%) (odds ratio (OR), 15.0; 95% confidence interval (CI), 5.67-39.76; P<0.0001) compared with the unknown HPV types (OR, 2.87; 95% CI, 0.89-9.22; P=0.08). HPV 16 was the predominant oncogenic HPV type in CIN 2/3 (51%) and carcinoma (71%) and integrated significantly more frequently in carcinoma than in CIN 2/3 (P=0.004). No significant differences in viral load were observed across the disease categories. Our findings suggest that selected genotyping for the eight oncogenic HPV types might be useful in separating women with a higher risk of CIN progression from those with a minimal risk. We also conclude that the HPV 16 integration status has potential to be a marker for risk assessment of CIN progression.

DNA tumor viruses and human cancer

There is a strong association between viruses and the development of human malignancies. A group of oncogenic DNA viruses exists in the human population today, members of which serve as infectious agents of cancer worldwide. The group includes the Epstein-Barr virus, Kaposi's sarcoma-associated herpesvirus, human papillomaviruses and human polyomaviruses. Globally, it is estimated that 20% of all cancers are linked to infectious agents. Studies of DNA viruses have contributed to our current understanding of the key molecular players in the transformation process. Research has also shed light on the molecular mechanisms of tumorigenesis that are employed by these viruses and there are indications that cofactors could be required for viral oncogenicity in some cases.

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.

Molecular biology of squamous cell carcinoma of the anus

BACKGROUND

Squamous cell carcinoma of the anal canal provides a model for studying the contribution of human papillomavirus (HPV) and human immunodeficiency virus (HIV) infection to the development of neoplasia. This paper reviews the existing literature relating to the molecular biology of anal squamous cell carcinoma and proposes a theory of pathogenesis.

METHODS

A Medline literature search was performed to identify English articles on the pathogenesis of squamous cell carcinoma of the anus; further articles were obtained from the references quoted in the literature initially reviewed.

RESULTS

HPV infection and subsequent HPV DNA integration are necessary, but not sufficient, to cause cancer progression. Loss of heterozygosity at 11q23 is the most consistent genomic change observed. Loss of heterozygosity at 17p, 18q and 5q is frequently observed in tumours of HIV-negative patients, but not in those of HIV-positive patients. Current data suggest that mutations in p53, DCC and APC tumour suppressor genes contribute to the stepwise progression of anal squamous cell carcinoma in immunocompetent individuals.

CONCLUSION

In comparison with immunocompetent individuals, HIV-positive patients have persistent HPV infection in the anal canal. In this population, microsatellite instability, rather than chromosomal instability, appears to be a preferred pathway for rapid progression towards invasive carcinoma.

Early integration of high copy HPV16 detectable in women with normal and low grade cervical cytology and histology

BACKGROUND

Integration of human papillomavirus (HPV) DNA has been considered a late event in cervical carcinogenesis. However, integrated forms of HPV were recently detected in cancer precursor lesions using a new real time polymerase chain reaction (PCR) to detect the deletions at the 3362-3443 region of HPV16 E2 OBJECTIVE: To study the frequency of HPV16 DNA integration in cervical lesions and compare the sensitivity of an additional upstream region of the E2 ORF (2962-3138) in detecting HPV integration.

METHODS

Using the TaqMan based PCR, HPV16 positive DNA samples were analysed in 164 cervical scrapings from women participating in a multicentre screening trial. Biopsy confirmation was available in 62 cases.

RESULTS

Primers targeting the 3362-3443 region detected the majority of E2 deletions. In only 23% of the samples was the E2 upstream region equal or better target than the 3362-3443 region. Mixed (episomal/integrated) pattern was the most prevalent physical state of HPV16, also present in PAP smears with normal morphology. Pure integrated form was most prevalent in HSIL and cancer lesions, but also detectable in low grade abnormalities (NSIL, ASC-US, LSIL). Women with only integrated HPV16 were almost 10 years older than those with episomal HPV16. Viral load of integrated HPV16 was related to cytological abnormality (p = 0.003) but not to histology.

CONCLUSIONS

Integrated HPV16 is present in low grade cervical lesions, mostly mixed with the episomal form. Women with the pure integrated form of HPV16 are older than those with the other forms.

Integration of HPV-16 and HPV-18 DNA in vulvar intraepithelial neoplasia

OBJECTIVE

Vulvar intraepithelial neoplasia (VIN) is a premalignant disease of the lower genital tract. The increased occurrence of high-risk human papillomavirus (HPV) infection seems to be associated with the increasing frequency of VIN. Integration of HPV DNA into host chromosome has been hypothesized to be a critical step in the carcinogenesis of cervical neoplasia resulting in altered expression of two viral transforming genes E6 and E7.

METHOD

We analyzed HPV-16 and HPV-18 DNA, and integrated transcripts of HPV-16 and HPV-18 genomes in 30 VIN cases with 53 lesions using a PCR-based protocol for the amplification of papillomavirus oncogene transcripts (APOT).

RESULT

24 of 30 VIN lesions (80%) harbored HPV-16 (in 23 cases) and HPV-18 DNA. Integration of HPV-16 and HPV-18 genome was observed in eight (38.1%) of 21 HPV-16/18 positive VIN III cases. All eight VIN were multifocal and had multicentric disease (CIN/VAIN) including one case that progressed to vulvar carcinoma. Five of eight lesions were found to have E7 specific viral-cellular fusion transcripts only, two of eight showed E7-E4 viral-cellular fusion transcripts, and one of eight had both episomally derived and E7-E4 viral-cellular fusion transcripts. In 10 (83.3%) of 12 multifocal VIN III patients, all specimens derived from the same patient harbored the same HPV type and HPV transcript pattern suggesting monoclonality.

CONCLUSION

HPV-16 is the most prevalent type among VIN II/III. HPV-16 and HPV-18 DNA integration into host cell genome seems to be related to the progression stage of vulvar dysplasia and, therefore, may be necessary for development of HPV-associated invasive vulvar carcinoma.

Good correlation of HPV DNA test between self-collected vaginal and clinician-collected cervical samples by the oligonucleotide microarray

OBJECTIVES

To evaluate the efficacy of self-collected vaginal samples for high-risk HPV detection by the HPV oligonucleotide microarray method (HPVDNAChip).

METHODS

One hundred and eighteen patients with abnormal Pap smears were included. Self-collected vaginal and clinician-collected cervical samples for HPV testing were obtained. The result of the HPV DNA test was compared with the histopathological diagnosis or colposcopic finding.

RESULTS

Of the 118 patients, 42 (35.6%) had >or= cervical intraepithelial neoplasia (CIN) III lesions. Using the HPVDNAChip, high-risk types of HPV were detected in 38 of these 42 patients (90.5%) with the self-collected vaginal samples and in 37 of 42 (88.1%) with the clinician-collected cervical samples. The agreement of HPVDNAchip results between self- and clinician-collected samples was very good (kappa = 0.81) with a 93.2% concordance rate. Multiple HPV infections were found in 17 of 88 (19.3%) HPV-positive clinician-collected cervical samples. The rate of multiple HPV infection tended to decrease as the degree of pathologic classification increased.

CONCLUSION

Using the HPVDNAchip to assay for HPV infection, results from self-collected vaginal samples were compatible with those from clinician-collected cervical samples.

Detection and typing of human papillomavirus DNA in uterine cervices with coexistent grade I and grade III intraepithelial neoplasia: biologic progression or independent lesions?

OBJECTIVE

To examine the HPV type infection of cervical cone specimens with coexistent CIN1 and CIN3 lesions, in order to define if coexistence of low- and high-grade lesions in the same cervix represent different stages of evolution in a continuing process that is caused by a single viral type or independent lesions induced by different HPV types.

STUDY DESIGN

The examined material included 43 cases with coexistent CIN1 and CIN3 in the cone biopsy specimen. Detection and typing of HPV was made by RFLP-PCR.

RESULTS

All CIN1 lesions were HPV positive, while three CIN3 lesions were HPV-negative. The proportion of agreement of the HPV type in the two lesions, excluding negative cases (n = 40), was 60% (95% confidence interval: 43.3-75.1). HPV 16 was the most common type in both CIN3 (56.8%) and CIN1 (46.5%).

CONCLUSIONS

The so-called morphologic progression of CIN is not always synonymous with biologic progression, since many coexistent CIN lesions are caused by different HPV types, and so represent different cell clones. Clonality of coexistent CIN lesions may be implicated in the evolution of CIN as other recent studies have shown.

Epigenetics of cervical cancer. An overview and therapeutic perspectives

Cervical cancer remains one of the greatest killers of women worldwide. It is difficult to foresee a dramatic increase in cure rate even with the most optimal combination of cytotoxic drugs, surgery, and radiation; therefore, testing of molecular targeted therapies against this malignancy is highly desirable. A number of epigenetic alterations occur during all stages of cervical carcinogenesis in both human papillomavirus and host cellular genomes, which include global DNA hypomethylation, hypermetylation of key tumor suppressor genes, and histone modifications. The reversible nature of epigenetic changes constitutes a target for transcriptional therapies, namely DNA methylation and histone deacetylase inhibitors. To date, studies in patients with cervical cancer have demonstrated the feasibility of reactivating the expression of hypermethylated and silenced tumor suppressor genes as well as the hyperacetylating and inhibitory effect upon histone deacetylase activity in tumor tissues after treatment with demethylating and histone deacetylase inhibitors. In addition, detection of epigenetic changes in cytological smears, serum DNA, and peripheral blood are of potential interest for development of novel biomolecular markers for early detection, prediction of response, and prognosis.

Comparison between in situ hybridization and real-time PCR technique as a means of detecting the integrated form of human papillomavirus 16 in cervical neoplasia

Integration of the human papillomavirus (HPV) genome is thought to be one of the causes of cancer progression. However, there is controversy concerning the physical status of HPV 16 in premalignant cervical lesions, and there have been no reports on the concordance between detection of the integrated form of HPV16 by real-time PCR and by in situ hybridization. We investigated specimens of cervical intraepithelial neoplasia (CIN) and invasive carcinomas for the physical status of HPV 16 by real-time PCR and in situ hybridization. The presence of the integrated form was detected by both real-time PCR and in situ hybridization in zero of four cases of CIN1, three of six cases of CIN2, nine of 27 cases of CIN3, and two of six cases of invasive carcinomas. Integrated HPV 16 was present in some premalignant lesions but was not always present in carcinomas. The concordance rate between the two methods for the detection of the presence of the integrated form was 37 of 43 (86%) cases. Real-time PCR and in situ hybridization were found to be complementary and convenient techniques for determining the physical status of the HPV genome. We conclude that a combination of both methods is a more reliable means of assessing the physical status of the HPV genome in cervical neoplasia.

P16INK4a expression and progression risk of low-grade intraepithelial neoplasia of the cervix uteri

The aim of the study was to evaluate the immunohistochemical expression of p16INK4a as a marker of progression risk in low-grade dysplastic lesions of the cervix uteri. p16INK4a immunohistochemistry was performed on 32 CIN1 with proven spontaneous regression of the lesion in the follow-up (group A), 31 (group B) with progression to CIN3 and 33 (group C) that were randomly chosen irrespective of the natural history of the lesion. p16INK4a staining pattern was scored as negative (less than 5% cells in the lower third of dysplastic epithelium stained), as focally positive (< or = 25%) and as diffuse positive (> 25%). A diffuse staining pattern was detected in 43.8% of CIN1 of group A, 74.2% of group B and 56.3% of group C. No p16INK4a staining was detected in 31.3% and 12.9% CIN1 lesions of groups A and B, respectively. Overall, 71.4% and 37.8% of p16INK4a-negative and diffusely positive CIN1 had regressed at follow-up, whereas 28.6% and 62.2% negative and diffusely positive CIN1 were progressed to CIN3, respectively (P < 0.05). All CIN3 lesions analyzed during follow-up of group B were diffusely stained for p16INK4a. Although p16INK4a may be expressed in low-grade squamous lesions that undergo spontaneous regression, in this study, CIN1 cases with diffuse p16INK4a staining had a significantly higher tendency to progress to a high-grade lesion than p16INK4a-negative cases. p16INK4a may have the potential to support the interpretation of low-grade dysplastic lesions of the cervix uteri.