Molecular biology of cervical cancer and its precursors

Non-apoptotic cell death programs in cervical cancer with an emphasis on ferroptosis

BACKGROUND

Cervical cancer, a pernicious gynecological malignancy, causes the mortality of hundreds of thousands of females worldwide. Despite a considerable decline in mortality, the surging incidence rate among younger women has raised serious concerns. Immortality is the most important characteristic of tumor cells, hence the carcinogenesis of cervical cancer cells pivotally requires compromising with cell death mechanisms.

METHODS

The current study comprehensively reviewed the mechanisms of non-apoptotic cell death programs to provide possible disease management strategies.

RESULTS

Comprehensive evidence has stated that focusing on necroptosis, pyroptosis, and autophagy for disease management is associated with significant limitations such as insufficient understanding, contradictory functions, dependence on disease stage, and complexity of intracellular pathways. However, ferroptosis represents a predictable role in cervix carcinogenesis, and ferroptosis-related genes demonstrate a remarkable correlation with patient survival and clinical outcomes.

CONCLUSION

Ferroptosis may be an appropriate option for disease management strategies from predicting prognosis to treatment.

High-Risk Human Papillomavirus Infection in Lung Cancer: Mechanisms and Perspectives

Lung cancer is a very prevalent and heterogeneous group of malignancies, and most of them are etiologically associated with tobacco smoking. However, viral infections have been detected in lung carcinomas, with high-risk human papillomaviruses (HR-HPVs) being among them. The role of HR-HPVs in lung cancer has been considered to be controversial. This issue is due to the highly variable presence of this virus in lung carcinomas worldwide, and the low viral load frequently that is detected. In this review, we address the epidemiological and mechanistic findings regarding the role of HR-HPVs in lung cancer. Some mechanisms of HR-HPV-mediated lung carcinogenesis have been proposed, including (i) HPV works as an independent carcinogen in non-smoker subjects; (ii) HPV cooperates with carcinogenic compounds present in tobacco smoke; (iii) HPV promotes initial alterations being after cleared by the immune system through a "hit and run" mechanism. Additional research is warranted to clarify the role of HPV in lung cancer.

The ‘Why and How’ of Cervical Cancers and Genital HPV Infection

Knowing about the virology of human papillomavirus (HPV) including its structure, functions and mechanism of infection, helps in understanding the disease process and morphology of precancerous lesions for cervical cancer. Two types of HPV, low- and high-risk type, adopt different mechanisms of infection which cannot be differentiated on morphological basis. In addition to HPV infection, many other factors such as genetic predisposition, hormonal factors, host immune response, and multiple sexual partners can modify the course and progression of the disease. The viral genome comprises early and late proteins. These early and late genes are expressed in particular course of time after initial infection. Various products of early genes (E1–E7) coordinate for completion of viral life cycle in maturing squamous epithelium by utilizing replication factors and DNA polymerase enzyme of the host cell nucleus. The late genes are mainly concerned with packaging of the viral particles and their release through mature squamous cells. The episomal form of infection seen in the low-risk group of viruses results in productive infection whereas the integrated form seen in high-risk group of viruses is the basis of disruption of host cell growth cycle by inactivating two important tumor suppressor genes p53 and Rb gene by products of E6 and E7 genes. Cervical precancerous lesions and cancer are the resultant effect of the accumulation of mutations. This article discusses the virology of HPV, pathogenesis of HPV infection, and various other factors modifying the disease course.

The Impact of 9-Valent HPV Vaccination on Couple Infertility Prevention: A Comprehensive Review

A comprehensive literature review was performed to determine the relationship between HPV infection and infertility and the eventual role of the 9-valent vaccine for infertility prevention. The search was extended from January 1997 through July 2021. Data collected from selected articles focused on three main topics: statistical associations between HPV prevalence and assisted reproductive technology (ART) outcome, association between HPV and characteristics of semen, and associations between HPV and miscarriage. Articles that identified HPV genotypes were selected for this review to study the possible role of the 9-valent vaccine in infertility prevention. To date, there is no agreement on the implication HPV female infection has on the fertility and miscarriage rate. Although it can be stated that HPV prevalence among couples with infertility undergoing ART treatment is consistent, it does not seem to affect the performance of oocytes. Otherwise, HPV infection affects sperm parameters, in particular spermatozoa motility. When an association can be found, most cases of HR-HPV involved are those included in the 9-valent vaccine. The correlation between HPV male infection both with asthenozoospermia and increased risk of pregnancy loss could recommend the extension of anti-HPV vaccination to adolescent males along with cancer prevention. Despite the fact that the relation between 9-valent HPV genotypes involved in female infection and miscarriage/infertility is not clear, the impact of this virus on health reproduction is evident. Considering this, the importance of HPV vaccination in adolescent females is confirmed. A vaccine efficacy study could be useful to confirm the importance of primary prevention for couple reproductive health.

MicroRNA‑145‑5p suppresses fascin to inhibit the invasion and migration of cervical carcinoma cells

MicroRNAs (miRs) can affect the progression of cervical cancer (CC). The present study investigated the function of miR-145-5p in CC and demonstrated its association with fascin (FSCN1). The expression levels of miR-145-5p in CC tissues and cell lines were analyzed using reverse transcription-quantitative PCR, and its direct targets were explored using a luciferase reporter assay. The viability, migration and invasion of HeLa cells transfected with small interfering FSCN1 or with miR-145-5p mimics and inhibitors were analyzed using Cell Counting Kit-8 and Transwell assays. The expression levels of FSCN1 mRNA and protein were investigated using reverse transcription PCR and western blotting. miR-145-5p was downregulated in CC tissues and cell lines. Moreover, overexpression of miR-145-5p inhibited the migration, invasion and viability of HeLa cells. miR-145-5p directly targeted FSCN1, which regulated the suppressive functions of miR-145-5p in CC cells. Overall, miR-145-5p is a tumor suppressor gene and a promising target for CC treatment.

MiR-29a inhibits cell proliferation and migration by targeting the CDC42/PAK1 signaling pathway in cervical cancer

Cervical cancer is the second most common gynecological malignancy worldwide and the tumorigenesis mechanisms of cervical cancer are still unclear. This study aimed to reveal the role of miR-29a in cervical cancer. The expression level of miR-29a and CDC42 was measured using qRT-PCR. Cell proliferation, apoptosis, migration, and invasion were detected using colony formation, flow cytometry analysis, wound-healing assay, and Transwell assay, respectively. Luciferase reporter assay was used to determine the binding of miR-29a with CDC42. CDC42/p21-activated kinase 1 (PAK1) pathway-related proteins were measured by western blotting. MiR-29a was downregulated and CDC42 was upregulated in cervical cancer cells. Luciferase reporter assay showed that miR-29a negatively regulated the expression of CDC42 by directly targeting 3'-UTR of CDC42. Cell proliferation, migration, and invasion were markedly inhibited, whereas cell apoptosis was significantly increased in Hela and CaSki cells transfected with miR-29a mimics. These effects were partly recovered by CDC42 overexpression. Protein levels of PAK1, p-PAK1, p-LIMK, and p-cofilin were significantly downregulated by miR-29a mimics, which was reversed by CDC42 overexpression and was increased by the miR-29a inhibitor. MiR-29a inhibited cell proliferation, migration, and invasion, as well as promoted cell apoptosis through repressing the PAK1/LIMK signaling pathway by targeting CDC42 in cervical cancer.

RNA-based high-risk HPV genotyping and identification of high-risk HPV transcriptional activity in cervical tissues

Nearly all cervical cancers are initiated by a persistent infection with one of the high-risk human papillomaviruses (high-risk HPV). High-risk HPV DNA testing is highly sensitive but cannot distinguish between active, productive infections and dormant infections or merely deposited virus. A solution for this shortcoming may be the detection of transcriptional activity of viral oncogenes instead of mere presence of high-risk HPVs. In this study, fresh-frozen cervical tissues (n = 22) were subjected to high-risk HPV DNA detection using the line probe assay and to targeted RNA next-generation sequencing using single-molecule molecular inversion probes. Targeted RNA sequencing was applied for (1) RNA-based genotyping of high-risk HPV, giving information on specific HPV-subtype (2) discrimination of E2, E6, and E7 transcripts and (3) discovery of possible non-HPV cancer biomarkers. Data were analyzed using computational biology. Targeted RNA sequencing enabled reliable genotyping of high-risk HPV subtypes and allowed quantitative detection of E2, E6, and E7 viral gene expression, thereby discriminating cervical lesions from normal cervical tissues. Moreover, targeted RNA sequencing identified possible cervical cancer biomarkers other than high-risk HPV. Interestingly, targeted RNA sequencing also provided high-quality transcription profiles from cervical scrape samples, even after 1 week of dry storage or storage in Preservcyt fixative. This proof of concept study shows that targeted RNA sequencing can be used for high-risk HPV genotyping and simultaneous detection of high-risk HPV gene activity. Future studies are warranted to investigate the potential of targeted RNA sequencing for risk assessment for the development of cervical lesions, based on molecular analysis of cervical scrapes.

Intra-patient viral evolution in polyomavirus-related diseases

Human polyomaviruses show relatively little genetic polymorphism between isolates, indicating that these viruses are genetically stable between hosts. However, it has become increasingly clear that intra-host molecular evolution is a feature of some polyomavirus (PyV) infections in humans. Mutations inducing premature stop codons in the early region of the integrated Merkel cell PyV genome lead to the expression of a truncated form of the large tumour (LT) antigen that is critical for the transformation of Merkel cell carcinoma (MCC) cells. Non-coding control region (NCCR) rearrangements and point mutations in virion protein (VP) 1 have been described in both JCPyV and BKPyV infections. In the context of JCPyV infection, molecular evolution at both these loci allows the virus to replicate effectively in the central nervous system, thereby leading to the development of progressive multifocal leukoencephalopathy (PML). In BKPyV infection, NCCR rearrangements have been linked to higher rates of virus replication in the kidney, and are proposed to play a direct causal role in the development of PyV-associated nephropathy. In all three of these infections, therefore, intra-host viral evolution appears to be an essential component of the disease process. This article is part of the theme issue 'Silent cancer agents: multi-disciplinary modelling of human DNA oncoviruses'.

Monoclonal Antibodies Against Human Papillomavirus E6 and E7 Oncoproteins Inhibit Tumor Growth in Experimental Cervical Cancer

Nearly all cases of cervical cancer are initiated by persistent infection with high-risk strains of human papillomavirus (hr-HPV). When hr-HPV integrates into the host genome, the constitutive expression of oncogenic HPV proteins E6 and E7 function to disrupt p53 and retinoblastoma regulation of cell cycle, respectively, to favor malignant transformation. HPV E6 and E7 are oncogenes found in over 99% of cervical cancer, they are also expressed in pre-neoplastic stages making these viral oncoproteins attractive therapeutic targets. Monoclonal antibodies (mAbs) represent a novel potential approach against the actions of hr-HPV E6 and E7 oncoproteins. In this report, we describe the utilization of anti-HPV E6 and HPV E7 mAbs in an experimental murine model of human cervical cancer tumors. We used differential dosing strategies of mAbs C1P5 (anti-HPV 16 E6) and TVG701Y (anti-HPV E7) administered via intraperitoneal or intratumoral injections. We compared mAbs to the action of chemotherapeutic agent Cisplatin and demonstrated the capacity of mAbs to significantly inhibit tumor growth. Furthermore, we investigated the contribution of the immune system and found increased complement deposition in both C1P5 and TVG701Y treated tumors compared to irrelevant mAb therapy. Taken together, the results suggest that anti-HPV E6 and E7 mAbs exert inhibition of tumor growth in a viral-specific manner and stimulate an immune response that could be exploited for an additional treatment options for patients.

miR-145 Contributes to the Progression of Cervical Carcinoma by Directly Regulating FSCN1

The purpose of our study was to investigate the underlying mechanism and functional role of microRNA-145 (miR-145) in cervical cancer. In this study, quantitative real-time PCR (qRT-PCR) was used to detect miR-145 and FSCN1 expression levels in tissues and HeLa cells. Western blotting was performed to determine the protein level of FSCN1. The luciferase assay was used to verify the direct target of miR-145. The CCK-8 assay and 2D colony formation assays were performed to determine the effects of miR-145 mimics or FSCN1 silencing on cell proliferation. miR-145 expression levels were significantly down-regulated, while FSCN1 expression levels were significantly up-regulated in the cervical carcinoma tissues compared with their matched non-cancerous tissues. In addition, FSCN1 expression levels were negatively correlated to miR-145 in tissues. Next, FSCN1 was verified as the direct target of miR-145 in HeLa cells. Moreover, overexpression of miR-145 dramatically inhibited the proliferation of HeLa cells. The silencing of FSCN1 exhibited the similar patterns on cell proliferation as miR-145 overexpression. The miR-145/ FSCN1 axis contributes to the progression of cervical cancer by inhibition of cervical cancer cell proliferation.

Characterization and clinical validation of MCM2 and TOP2A monoclonal antibodies in the BD ProEx™ C assay: An immunoassay which detects aberrant S-phase induction in cervical tissue

BACKGROUND

The Papanicolaou (Pap) screen has been successful in reducing cervical cancer; but exhibits low sensitivity when detecting cervical dysplasia. Use of molecular biomarkers in Pap tests may improve diagnostic accuracy.

DESIGN

Monoclonal antibodies to Minichromosome Maintenance Protein 2 (MCM2) and DNA Topoisomerase II α (TOP2A) were selected for use in IHC based on their ability to differentiate normal from diseased cervical tissues in tissue microarrays. Enhanced Green Fluorescent Protein Western blot analysis was used to help identify binding epitopes specific to MCM2 and TOP2A antibody clones. Antibody affinity was determined by solution phase affinity measurement and immunohistochemistry was performed using high affinity MCM2 or TOP2A antibodies on serial histological sections.

RESULTS

Antibody clones to MCM2 and TOP2A clones were selected based on their ability to detect over expression in abnormal cervical epithelia. In IHC, MCM2-27C5.6 and MCM2-26H6.19 demonstrated superior staining in abnormal cervical tissue over the MCM2-CRCT2.1 antibody. A combination of MCM2 and TOP2A antibodies showed greater staining when compared to staining with any of the antibodies alone on serial histological sections. Distinct linear epitopes were elucidated for each of the MCM2 and TOP2A clones. Affinity values (Kd) for MCM2 or TOP2A antibodies had a similar range. In a research study, the MCM2 and TOP2A (BD ProEx™ C) antibody cocktail showed increased epithelia staining with increasing dysplasia. The use of BD ProEx™ C in combination with H&E staining enhanced immunohistochemical discrimination of dysplastic and non-dysplastic FFPE cervical tissue specimens.

CONCLUSIONS

BD ProEx™ C containing MCM2 and TOP2A antibodies showed strong specific nuclear staining that correlated with increased dysplasia and lesion severity. Enhanced performance of the antibodies was linked to their unique topography recognition. BD ProEx™ C incorporates antibodies that enhance detection of CIN2+ cervical disease.

Triage of high-risk HPV positive women in cervical cancer screening

INTRODUCTION

High-risk human papillomavirus (hrHPV) testing is expected to replace cytology as primary screening method for cervical cancer screening in an increasing number of countries. The high sensitivity of hrHPV testing is combined with a limited specificity which makes triaging of hrHPV positive women necessary. As an ideal triage method does not yet exist, an optimal triage strategy for hrHPV positive women based on current knowledge should be obtained. The aim of this article is to present an overview of available options for triage of hrHPV positive women, with their strengths and limitations and possible future opportunities.

AREAS COVERED

Current knowledge on morphological biomarkers, molecular biomarkers and combined triage strategies will be discussed to give an overview of the state-of-the-art on triaging hrHPV positive women. The literature search was limited to studies on triage strategies for hrHPV positive women. Expert commentary: Experience with morphology-based biomarkers makes these a valuable triage method. However, they lack the ability of differentiating productive from transforming infections. Molecular biomarkers are objective, highly reproducible, can be used in high throughput testing, and show promising results. With more extensive knowledge on these molecular markers, cervical cancer screening may transform to a full molecular screening in the future.

High Expression of Human Telomerase Reverse Transcriptase in High-Grade Intraepithelial Neoplasia and Carcinoma of Uterine Cervix and Its Correlation With Human Papillomavirus Infection

Most of cervical intraepithelial neoplasia 1 (CIN 1) will regress and 12% to 40% of high-grade CIN may progress to squamous cell carcinoma (SCC) of the uterine cervix. However, the differentiation of CIN 1 and high-grade CIN is sometimes controversial among pathologists. Human telomerase reverse transcriptase (hTERT) is therefore applied to detect the differences among normal, CIN 1, high-grade CIN, and SCC tissues of uterine cervix. One hundred six cervical specimens were collected for immunohistochemical study of hTERT. These data were compared with the human papillomavirus (HPV) DNA status. Expression of hTERT in high-grade CIN increased significantly compared to that in CIN 1 ( P < .001). A positive relationship was found between high hTERT expression and degree of malignant transformation ( P < .001). Most of the cases with high hTERT expression tested positive for the high-risk HPV groups. High hTERT expression was detected in 88.73% of the samples with cervical high-grade CIN or SCC. Low hTERT expression was found in 94.29% of low-grade CIN or normal tissues. Furthermore, 96.92% of the cervical tissues with high hTERT expression were high-grade CIN or SCC. A total of 80.49% of samples with low hTERT expression were low-grade CIN or normal tissues. A significantly increased hTERT expression between CIN 1 and high-grade CIN exhibits a critical progression in cervical carcinogenesis. hTERT can be offered as additional molecular information correlated with more severe dysplasia and SCC. Furthermore, this increased hTERT expression is correlated whigh-risk HPVs infection.

Molecular Detection and Typing of Human Papillomaviruses in Paraffin-Embedded Cervical Cancer and Pre-Cancer Tissue Specimens

Background:

Cervical cancer is one of the important reasons of mortality among females. Prevention, early diagnosis and immediate treatment can affect the rate of mortality in this cancer and several epidemiological studies have shown a strong relationship between human papilloma viruses (HPVs) and cervical cancer.

Objectives:

The present study was conducted to survey HPV infections in a women population with cervical cancer and cervical dysplasia/metaplasia in southwest of Iran.

Materials and Methods:

72 paraffin-embedded cervical biopsies which had been previously archived from women with cervical cancer and cervical dysplasia were examined by polymerase chain reaction (PCR). Afterward, the detected HPV strains were typed by restriction fragment length polymorphism (RFLP) analysis of PCR amplicons.

Results:

60 out of 72 samples had necessary requirements and HPV DNA was detected in 43.3% of these samples. Most HPV positive samples belonged to women aged from 48 to 63 years. On the other hand, HPV infection among patients with squamous cell carcinoma (SCC) was 48.78% and in women with dysplasia/metaplasia was 26.66%. The most prevalent type of the human papilloma virus was HPV16 (100%).

Conclusions:

Knowing the most prevalent type of the human papilloma viruses circulating in the population (HPV16) can be applied in the future screening and managing programs of this major disease and also in vaccination against the prevalent types of the virus. Meanwhile, it seems that more studies should be performed to determine the role of different risk factors involved in development of the disease, especially those related with social behaviors and traditions with respect to different areas.

c-myc copy number gain is a powerful prognosticator of disease outcome in cervical dysplasia

Cervical carcinoma develops from preneoplasia by a multistep process. Although most low-grade dysplastic lesions will regress without intervention and even high-grade changes exhibit a substantial rate of regression, a small percentage of dysplasia will progress over time. Thus, indicators are needed to estimate the biological risk and to help avoid overtreatment in women who desire to preserve fertility. In addition to the classical biomarkers, PCR-ELISA-determined HPV genotype and immunohistochemically assessed p16^INK4a and Ki-67 expression, cells with integrated HPV and copy number gain of TERC and c-myc were quantified in a panel of 104 benign, intraepithelial neoplastic (CIN I, II, III) and cancerous lesions using fluorescence in situ hybridization. Optimal cut-off values were calculated; Kaplan-Meier curves and a Cox proportional hazard regression model were used to evaluate prognostic signatures. The assay reliably identified HPV integration, TERC and c-myc copy number gain as determined by comparisons with established biomarkers. All biomarker levels increased with the progression of the disease. However, only c-myc copy number gain independently prognosticated a low probability of dysplastic regression. Our results suggest that c-myc plays a key role in the process of dysplastic transformation and might thus be exploited for treatment and follow-up decision-making of cervical dysplasia.

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.

[Cervical cancer: particularities in HIV patients]

Cervical cancer is the second most common cancer in women worldwide. It represents one of the most challenging public health problems in developing countries. HIV-infected women have a higher risk of cervical cancer which is an AIDS defining cancer. Cervical cancer treatment in HIV-infected and non-infected women is the same. HIV naive women must be prescribed combination antiretroviral therapy at the moment of HIV cancer diagnosis. A close collaboration between oncologist and infectiologist is mandatory to optimize HIV treatment. Among HIV-infected women, PAP-smear screening for early detection and treatment of precancerous cervical lesions is recommended. HPV vaccination is also recommended with the same efficacy and safety profile as the general population.

A Comprehensive Review of Dysregulated miRNAs Involved in Cervical Cancer

MicroRNAs(miRNAs) have become the center of interest in oncology. In recent years, various studies have demonstrated that miRNAs regulate gene expression by influencing important regulatory genes and thus are responsible for causing cervical cancer. Cervical cancer being the third most diagnosed cancer among the females worldwide, is the fourth leading cause of cancer related mortality. Prophylactic human papillomavirus (HPV) vaccines and new HPV screening tests, combined with traditional Pap test screening have greatly reduced cervical cancer. Yet, thousands of women continue to be diagnosed with and die of this preventable disease annually. This has necessitated the scientists to ponder over ways of evolving new methods and chalk out novel treatment protocols/strategies. As miRNA deregulation plays a key role in malignant transformation of cervical cancer along with its targets that can be exploited for both prognostic and therapeutic strategies, we have collected and reviewed the role of miRNA in cervical cancer. A systematic search was performed using PubMed for articles that report aberrant expression of miRNA in cervical cancer. The present review provides comprehensive information for 246 differentially expressed miRNAs gathered from 51 published articles that have been implicated in cervical cancer progression. Of these, more than 40 miRNAs have been reported in the literature in several instances signifying their role in the regulation of cancer. We also identified 40 experimentally validated targets, studied the cause of miRNAs dysregulation along with its mechanism and role in different stages of cervical cancer. We also identified and analysed miRNA clusters and their expression pattern in cervical cancer. This review is expected to further enhance our understanding in this field and serve as a valuable reference resource.

American cancer society guideline for the early detection of cervical neoplasia and cancer

An update to the American Cancer Society (ACS) guideline regarding screening for the early detection of cervical neoplasia and cancer, based on recommendations from a formal review and recent workshop, is presented. The new screening recommendations address when to begin screening, when screening may be discontinued, whether to screen women who have had a hysterectomy, appropriate screening intervals, and new screening technologies, including liquid-based cytology and HPV DNA testing.

Answering human papillomavirus vaccine concerns; a matter of science and time

Since the introduction of the HPV vaccine, questions have been asked about its efficacy in preventing cancer linked with HPV. Concerns about the HPV vaccine safety profile have also been raised. This paper highlights the rapidly growing body of evidence (including clinical trials and post-marketing surveillance) illustrating both the safety of the HPV vaccine, through a detailed investigation of reported adverse events, and its efficacy in reducing both HPV infections rates and the resulting drop in cervical lesions, which have been demonstrated to be good predictors of cervical cancer risk.

Direct human papillomavirus E6 whole-cell enzyme-linked immunosorbent assay for objective measurement of E6 oncoproteins in cytology samples

A novel, whole-cell enzyme-linked immunosorbent assay (ELISA) based on a non-type-specific anti-human papillomavirus (HPV) E6 antibody was tested on 182 residual cytological specimens. For samples with a designation of more severe than cervical intraepithelial neoplasia grade 3 (CIN3+), 83% tested positive for E6; in a subset with paired testing for E6 ELISA and HPV DNA, 72% tested E6 positive and 92% tested high-risk (HR)-HPV DNA positive (P = 0.2). Among the women with a less than CIN3 diagnosis, 31% and 47% tested positive for E6 and HR-HPV DNA, respectively (P = 0.0006).

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.

Physical and functional interactions of human papillomavirus E2 protein with nuclear receptor coactivators

In addition to the human papillomavirus (HPV)-induced immortalization of epithelial cells, which usually requires integration of the viral DNA into the host cell genome, steroid hormone-activated nuclear receptors (NRs) are thought to bind to specific DNA sequences within transcriptional regulatory regions on the long control region to either increase or suppress transcription of dependent genes. In this study, our data suggest that the NR coactivator function of HPV E2 proteins might be mediated through physical and functional interactions with not only NRs but also the NR coactivators GRIP1 (glucocorticoid receptor-interacting protein 1) and Zac1 (zinc-finger protein which regulates apoptosis and cell cycle arrest 1), reciprocally regulating their transactivation activities. GRIP1 and Zac1 both were able to act synergistically with HPV E2 proteins on the E2-, androgen receptor-, and estrogen receptor-dependent transcriptional activation systems. GRIP1 and Zac1 might selectively function with HPV E2 proteins on thyroid receptor- and p53-dependent transcriptional activation, respectively. Hence, the transcriptional function of E2 might be mediated through NRs and NR coactivators to regulate E2-, NR-, and p53-dependent transcriptional activations.

X chromosomal and autosomal loss of heterozygosity and microsatellite instability in human cervical carcinoma

The study analyzes tumor material and normal tissue from 27 patients with pure squamous cell carcinoma of the uterine cervix for loss of heterozygosity (LOH) and microsatellite instability (MSI) on 14 autosomal and 11 X chromosomal loci. Overall, 4-40% of the informative cases showed LOH at autosomal regions with the highest frequency at 3p (21-40%) and a marked frequency at 2q35-q37.1 (12.5%) and 17p13.3 (10%), representing regions with putative tumor suppressor gene (TSG) function. The frequency of X chromosomal LOH ranged from 4% to 20%, with a maximum at Xq28 (20%) and Xq11.2-q12 (17%), again indicating alterations in TSG. A 12% LOH was seen at Xq21.33-q22.3, a region encoding a protein with a regulatory function in the cell cycle via cyclin-dependent kinases. MSI was detected in autosomal regions in up to 7% in regions linked to the X chromosome in up to 11%, probably indicating alterations of mismatch repair mechanisms. Our results and those obtained from the literature suggest that autosomal LOH and MSI in carcinomas of the cervix uteri are predominantly found at regions with putative TSG function. Beside TSG alterations, X chromosomal LOH is probably more strongly connected to disturbances in cell cycle regulation.

Gene profiling in Pap-cell smears of high-risk human papillomavirus-positive squamous cervical carcinoma

OBJECTIVE

The purpose of the study was to investigate benign and malignant squamous cervical cells obtained by cervical swabs with regard to differentially expressed genes and gene expression profiling, in order to evaluate the biological behavior and clinical outcome of cervical malignancies.

METHODS

Cervical squamous cells from six women with high-risk human papillomavirus positive [HR-HPV(+)] cervical carcinoma and from six HPV-negative women with normal ectocervical cells were analyzed by cDNA array.

RESULTS

cDNA over-expression of several genes such as MET (c-met), Nm23-H1 (NME1), EGFR, KGFR, Nm23-H2 (NME2), ERBB2 (c-erbB-2), cyclin-dependent kinase inhibitor 4 (CDKN2A, p16INK4A), cytokeratin 8 (KRT8), KRAS (K-ras), FLT1, KGF (FGF7), BCL2-like 2 protein (BCL2L2), ERBB4, MYCN (N-myc), cyclin D1 (CCND1), KIT (c-kit), secreted phosphoprotein 1 (SPP1) and STAT1, was significant in cervical squamous cell carcinoma (CSCC). Gene expression was downregulated for 13 genes in CSCC, such as interleukin 1 alpha (IL1A), the transforming growth factor receptor beta superfamily (TGFbeta; TGFB), some members of the insulin-like growth factor binding proteins (IGFBPs) and the integrin family (ITGA6, ITGB1).

CONCLUSION

This study was focused on the gene expression profiling of HR-HPV(-) and (+) cervical squamous cells and CSCC obtained by cytobrush. We observed gene expression patterns and signaling pathways that permit the investigator to distinguish between benign squamous cervical cells and CSCC with and without HPV infection.

Human papillomavirus E2 protein associates with nuclear receptors to stimulate nuclear receptor- and E2-dependent transcriptional activations in human cervical carcinoma cells

Steroid hormones are proposed to act with human papillomaviruses (HPVs) as cofactors in the etiology of cervical cancer. Steroid hormone-activated nuclear receptors (NRs) are thought to bind to specific DNA sequences within transcriptional regulatory regions on the HPV DNA to either increase or suppress transcription of dependent genes. HPV-induced immortalization of epithelial cells usually requires integration of the viral DNA into the host cell genome. The integration event causes disruption of the E2 gene: the E2 protein is a transcription factor that regulates expression of the E6 and E7 oncoproteins by binding to four sites within the viral long control region (LCR). Our previous study suggested that E6 and E7 oncoproteins both directly bind to some NRs and serve as their cofactors. Here, we provide several lines of evidence demonstrating that the E2 protein is an NR coactivator through its physical interaction with NRs. In our study, the NR coactivator function of HPV E2 protein in human cervical carcinoma cells was independent of the type of E2, HPV transformation and the p53 status. Our observations also provide evidence suggesting regulatory mechanisms for the LCR involving interaction between the E2 protein and NRs in HeLa cells.

Immunological role of dendritic cells in cervical cancer

Cervical cancer is the second most frequent gynecological malignancy in the world. Human papillomavirus (HPV) infection is the primary etiologic agent of cervical cancer. However, HPV alone is not sufficient for tumor progression. The clinical manifestation of HPV infection depends also on the host's immune status. Both innate and adaptive immunity play a role in controlling HPV infection. In untransformed HPV-infected keratinocytes, the innate immunity is induced to eliminate the invading HPV pathogen through sensitization to HPV-related proteins by epithelial-residing Langerhans cells (LCs), macrophages, and other immune cells. Once the HPV infection escapes from initial patrolling by innate immunity, cellular immunity becomes in charge of killing the HPV-infected keratinocytes of the uterine cervix through systemic immune response developing by dendritic cells (DCs) in the regional lymphoid organs or through local immune response developing by LCs in the cervix. Thereby, DC/LC plays a critical role in eliciting innate and adaptive cellular immune responses against HPV infection. HPV-associated cervical malignancies might be prevented or treated by induction of the appropriate virus-specific immune responses in patients. Encouraging results from experimental vaccination systems in animal models have led to several prophylactic and therapeutic vaccine clinical trials.

Prevalence of cervical human papillomavirus in women undergoing in vitro fertilization and association with outcome

Human papillomavirus (HPV) was detected in 17 (16.0%) of 106 patients undergoing treatment for IVF. Human papillomavirus-positive women had a decreased pregnancy rate (4 of 17, 23.5%) as compared with HPV-negative women (51 of 89, 57.0%; P<.02).

Molecular cytogenetic characterization of human papillomavirus16-transformed foreskin keratinocyte cell line 16-MT

Anogenital cancers are closely associated with human papillomavirus (HPV), and HPV-infected individuals, particularly those with high-grade dysplasias, are at increased risk for cervical and anal cancers. Although genomic instability has been documented in HPV-infected keratinocytes, the full spectrum of genetic changes in HPV-associated lesions has not been fully defined. To address this, we examined an HPV16-transformed foreskin keratinocyte cell line, 16-MT, by GTG-banding, spectral karyotyping (SKY), and array comparative genomic hybridization (array CGH); these analyses revealed multiple numerical, complex, and cryptic chromosome rearrangements. Based on GTG-banding, the 16-MT karyotype was interpreted as 78-83,XXY,+add(1)(p36.3),+3,+4,+5,+5,+7,+8,+i(8)(q10)x2,+10,?der(12),der(13;14)(q10;q10),+15,+16,add(19)(q13.3),+21,+21,-22[cp20]. Multicolor analysis by SKY confirmed and further characterized the anomalies identified by GTG banding. The add(1) was identified as a der(1)(1qter-->1q25::1p36.1-->1qter), the add(19) as a dup(19), and the der(12) interpreted as a der(11) involving a duplication of chromosome 11 material and rearrangement with chromosome 19. In addition, previously unidentified der(9)t(9;22), der(3)t(3;19), and der(4)t(4;9) were noted. The 16-MT cell line showed losses and gains of DNA due to unbalanced translocations and complex rearrangements of regions containing known tumor suppressor genes. Chromosomal changes in these regions might explain the increased risk of cancer associated with HPV. Also, array CGH detected copy-number gains or amplifications of chromosomes 2, 8, 10, and 11 and deletions of chromosomes 3, 4, 11, and 15. These results provide the basis for the identification of candidate oncogenes responsible for cervical and anal cancer in amplified regions, and for putative tumor suppressor genes in commonly deleted regions like 11q22-23. Furthermore, these data represent the first full characterization of the HPV-positive cell line 16-MT.

Utilidad de la detección del virus del papiloma humano de alto riesgo mediante Hybrid Capture II® en mujeres con citologías anormales del cuello uterino

INTRODUCTION

The objectives of the study were to investigate the usefulness of high-risk human papillomavirus (HR-HPV) detection in women with abnormal pap-smears as an adjunct to screening by cervical cytology, and to determine the viral load distribution according to the histological grade of the lesions.

METHODS

A total of 75 women were referred for cytological study of atypical cells of unknown origin (ASCUS), low-grade squamous intraepithelial lesions (LG-SIL) or high-grade squamous intraepithelial lesions (HG-SIL). All patients underwent colposcopy, histological study and HR-HPV detection using the Hybrid Capture II test.

RESULTS

In the pap-smear studies, HR-HPV was detected in 31.2% of women with ASCUS and 65.7% with LG-SIL. Histological examination showed HR-HPV in 46.4% of women without lesions, 69.5% of those with LG-SIL and 75% with HG-SIL. Negative predictive values for HG-SIL in women with cytological diagnoses of ASCUS and LG-SIL were 81.8% and 92.3%, respectively. Percentages of infection with high viral load significantly increased in accordance with the histological grade.

CONCLUSIONS

The Hybrid Capture II test can be useful for the management of women with cytological evidence of ASCUS because of the low prevalence of HR-HPV infection and the high negative predictive value for HG-SIL. The usefulness in women with a cytological diagnosis of LG-SIL is limited due to the high prevalence of HR-HPV infection. High viral load can be a risk factor for the development of premalignant cervical lesions.

Induction of the human papillomavirus type 31 late promoter requires differentiation but not DNA amplification

The human papillomavirus (HPV) life cycle is linked to the differentiation state of the host cell. In virus-infected undifferentiated basal epithelial cells, HPV genomes are maintained as episomes at low copy number. Upon differentiation, a concomitant increase in viral copy number and an induction of late gene expression from a differentiation-specific promoter is seen. To investigate whether late gene expression was dependent on the amplification of the viral genome, inhibitors of DNA replication and in vitro systems for epithelial differentiation were used in conjunction with cells that stably maintain HPV31 episomes. Treatment of cells induced to differentiate in methylcellulose with the DNA synthesis inhibitor cytosine beta-arabinofuranoside (AraC) blocked viral DNA amplification but did not prevent induction of late transcription. This suggests that late gene expression does not strictly require amplification of the viral genome and that differentiation signals alone are sufficient to activate transcription from the late promoter. However, DNA amplification does appear to be necessary for maximal induction of the late promoter. In order to examine the cis-acting elements that contribute to the activation of the late promoter, a transient reporter assay was developed. In these assays, an induction of late gene expression was seen upon differentiation that was specific to the late promoter. Mapping studies localized important regulatory elements to the E6/E7 region and identified short sequences that could serve as binding sites for transcription factors. Elements within the upstream regulatory region were also found to positively and negatively influence transcription from the late promoter. These results identify mechanisms important for the differentiation-dependent activation of late gene expression of high-risk papillomaviruses.

cDNA array analysis of cytobrush-collected normal and malignant cervical epithelial cells: a feasibility study

Analysis of gene expression pattern is a useful approach to evaluating the biological behavior and clinical outcome of several human malignancies. Differentially expressed genes in malignant squamous cervical cells and the feasibility of gene expression profiling on squamous cervical cells obtained from cervical swabs were investigated. Cervical squamous cells from three women with high-risk human papilloma virus (HR-HPV) positive invasive squamous cervical carcinoma and from three HPV-negative women with normal ectocervical smears were analyzed with cDNA array. Immunoblot analysis was performed to detect the proteins corresponding to the highest upregulated genes with cDNA array. mRNA expression of ERBB2, KIT, FLT1, MYCN, RAS, CDKN2A, CCND1, NME1, NME2, MET, FGF7, FGFR2, and STAT1 was increased in malignant samples. Several expressed genes associated with antiapoptosis (such as BCL2), cell structuring, or cell attachment were also upregulated in carcinoma cells. Decreased gene expression was observed for members of the transforming growth factor receptor superfamily (TGF) and integrin family, interleukin 1 (IL1), and insulin-like growth factor binding proteins (IGFBPs). This study shows the feasibility of gene expression profiling of cervical squamous cells obtained with cytobrushes by identifying a characteristic gene expression pattern that clearly distinguishes between malignant and normal cervical epithelia of squamous type. We hypothesize that this noninvasive technique could be used in the evaluation of ambiguous Papanicolaou (PAP) smears.

Estrogen receptor, progesterone receptor, and bcl-2 are markers with prognostic significance in CIN III

There are no known biological markers or technologies to predict the natural history of an individual CIN III. The probability of progression is considered greater with the persistence of high-risk human papillomavirus (HPV) infection and age. p53 polymorphism has been associated with cervical carcinogenesis. Hormone-induced cervical cancer is mediated by estrogen receptor (ER) and progesterone receptor (PR). In cervical cancer, increased bcl-2 and Bax immunoreactivity is generally associated with a better prognosis. The purpose of this study was to evaluate the value of HPV 16 and HPV 18 typing and p53 codon polymorphism genotyping by polymerase chain reaction and ER, PR, bcl-2, and Bax expression by immunohistochemistry in predicting the CIN III clinical behavior of CIN III lesions. We studied the expression of these prognostic factors in the CIN III adjacent to squamous cell microinvasive carcinomas of the cervix (MIC) from 29 patients with FIGO stage IA1 cervical cancer and in 25 patients with CIN III and no documented focus of invasion. In the MIC group, only the CIN III was considered at least 2 mm away from the microinvasive complex. The ER, PR, bcl-2, and Bax immunoreactivity was scored as positive (>10% staining cells) and negative (<10% staining cells). No significant difference was observed between MIC and CIN III group concerning HPV infection and p53 polymorphism. The ER, PR, bcl-2, and Bax immunohistochemical expression was stronger and more frequent in the CIN III group. After multivariable analysis, coexpression of ER, PR, and bcl-2 was the only independent factor in defining low risk of progression for CIN III. Our study suggests that coexpression of ER, PR, and bcl-2 may be a useful tool in identifying the CIN III lesions with low risk of progression to cervical cancer.

ORC-associated replication factors as biomarkers for cancer

Early detection and treatment of cancer are of central importance to improving patient prognoses. Traditional biomarkers of cell proliferation, such as Ki-67 and PCNA, have had a mixed clinical track record, proving to be good indicators of certain types of cancers but of limited use for many others. Recently, human counterparts of replication factors originally identified in budding yeast have shown great promise as new cancer biomarkers. Each of these factors has been shown to interact with the origin recognition complex (ORC) in yeast, and each has an essential role in the initiation of DNA replication. Studies with minichromosome maintenance (MCM) family proteins show that their levels are upregulated in tumor cells and are much better indicators of a wide variety of cancers than traditional biomarkers. Similarly encouraging results have been obtained in preliminary studies examining Cdc6 protein and Cdc7 kinase transcript levels in normal and cancerous cells.

Expression of a Novel Human Gene,Human Wings Apart-Like (hWAPL), Is Associated with Cervical Carcinogenesis and Tumor Progression

In Drosophila melanogaster, the wings apart-like (wapl) gene encodes a protein that regulates heterochromatin structure. Here, we characterize a novel human homologue of wapl (termed human WAPL; hWAPL). The hWAPL mRNA was predominantly expressed in uterine cervical cancer, with weak expression in all other normal and tumor tissues examined. hWAPL expression in benign epithelia was confined to the basal cell layers, whereas in dysplasias it increasingly appeared in more superficial cell layers and showed a significant correlation with severity of dysplasia. Diffuse hWAPL expression was found in all invasive squamous cell carcinomas examined. In addition, NIH3T3 cells overexpressing hWAPL developed into tumors on injection into nude mice. Furthermore, repression of hWAPL expression by RNA interference induced cell death in SiHa cells. These results demonstrate that hWAPL is associated with cell growth, and the hWAPL expression may play a significant role in cervical carcinogenesis and tumor progression.

Concerted regulation of inorganic pyrophosphate and osteopontin by akp2, enpp1, and ank: an integrated model of the pathogenesis of mineralization disorders

Tissue-nonspecific alkaline phosphatase (TNAP) hydrolyzes the mineralization inhibitor inorganic pyrophosphate (PP(i)). Deletion of the TNAP gene (Akp2) in mice results in hypophosphatasia characterized by elevated levels of PP(i) and poorly mineralized bones, which are rescued by deletion of nucleotide pyrophosphatase phosphodiesterase 1 (NPP1) that generates PP(i). Mice deficient in NPP1 (Enpp1(-/-)), or defective in the PP(i) channeling function of ANK (ank/ank), have decreased levels of extracellular PP(i) and are hypermineralized. Given the similarity in function between ANK and NPP1 we crossbred Akp2(-/-) mice to ank/ank mice and found a partial normalization of the mineralization phenotypes and PP(i) levels. Examination of Enpp1(-/-) and ank/ank mice revealed that Enpp1(-/-) mice have a more severe hypermineralized phenotype than ank/ank mice and that NPP1 but not ANK localizes to matrix vesicles, suggesting that failure of ANK deficiency to correct hypomineralization in Akp2(-/-) mice reflects the lack of ANK activity in the matrix vesicle compartment. We also found that the mineralization inhibitor osteopontin (OPN) was increased in Akp2(-/-), and decreased in ank/ank mice. PP(i) and OPN levels were normalized in [Akp2(-/-); Enpp1(-/-)] and [Akp2(-/-); ank/ank] mice, at both the mRNA level and in serum. Wild-type osteoblasts treated with PP(i) showed an increase in OPN, and a decrease in Enpp1 and Ank expression. Thus TNAP, NPP1, and ANK coordinately regulate PP(i) and OPN levels. The hypomineralization observed in Akp2(-/-) mice arises from the combined inhibitory effects of PP(i) and OPN. In contrast, NPP1 or ANK deficiencies cause a decrease in the PP(i) and OPN pools that leads to hypermineralization.

Physical state and expression of HPV DNA in benign and dysplastic cervical tissue: different levels of viral integration are correlated with lesion grade

OBJECTIVE

Human papillomavirus (HPV) infection is the most important event in the malignant transformation of human cervical epithelium. Several high-risk (HR-)HPV subtypes have been identified, which lead to CIN and subsequently to invasive carcinoma. The reason for this phenomenon is still unknown, but it seems to be related to the physical state of HPV DNA.

METHODS

Digene HC II test was used to identify HR- and/or low-risk (LR-)HPV infections in cervical swabs of 275 women attending our clinic for routine cytological screening and/or colposcopy because of an abnormal Pap smear comprising low-grade squamous intraepithelial lesions (LGSIL) and high-grade SIL (HGSIL). Specific HR (16, 18, 31, 33, 52b, 58) and LR (6, 11) subtypes were characterized in cervical biopsies of 10 women with benign cellular changes and of 68 women with CIN I-III by the PCR-restriction enzyme method. The physical state of HPV DNA (episomal, mixed and integrated form) was analyzed by bi-dimensional (2D)-gel electrophoresis. In addition, mRNA expression of E6/E7 genes was analyzed by RT-PCR. Furthermore, the relative virus load was determined in nine selected cases. The physical state and transcriptional activity of HPV DNA were then correlated to histopathological results.

RESULTS

LR-HPV infection [27 cases (9.8%)] and HR-HPV infection [121 cases (44%)] of cervical swabs were clearly correlated to the degree of SIL. Further HPV typing in cervical biopsies of 78 women showed that HPV6 and 11 were restricted to benign cellular changes, CIN I and II, whereas HPV16 and 18 were observed predominantly in CIN III/CIS (P=0.01). No clear distribution pattern was observed for HPV31, 33, 52b and 58. Expression of HPV E6 and E7 transcripts was uniformly correlated with the different physical state of HPV DNA. Analyzing the physical state of these HPV subtypes, HPV6 and 11 could only be detected as an episomal form, independent of SIL grade. In normal epithelium and in CIN I and II, HPV16 and 18 were exclusively found in the episomal form. In CIN III/CIS, 15 of 30 cases of HPV16 (50%) and 16 of 17 cases of HPV18 (94%) were exclusively integrated into the host genome. Like HPV16/18, HPV31, 33, 52b and 58 were also present in the episomal form in normal epithelium and in CIN I and II, but were integrated in 80% of the CIN III/CIS (4/5) cases.

CONCLUSION

Absent integration of HPV16 DNA in some CIN III/CIS suggests that integration is not always required for progression early dysplastic lesions. In contrast, integration of HPV type 18 and others appears to be of major importance for the transforming efficacy of cervical dysplasia. The applied method represents a sensitive instrument to assess the physical state of HPV and is useful to predict the progression of disease.

Depletion of Langerhans cells in human papillomavirus type 16-infected skin is associated with E6-mediated down regulation of E-cadherin

Human papillomavirus type 16 (HPV16) is an oncogenic virus that causes persistent infections in cervical epithelium. The chronic nature of HPV16 infections suggests that this virus actively evades the host immune response. Intraepithelial Langerhans cells (LC) are antigen-presenting cells that are critical in T-cell priming in response to viral infections of the skin. Here we show that HPV16 infection is directly associated with a reduction in the numbers of LC in infected epidermis. Adhesion between keratinocytes (KC) and LC, mediated by E-cadherin, is important in the retention of LC in the skin. Cell surface E-cadherin is reduced on HPV16-infected basal KC, and this is directly associated with the reduction in numbers of LC in infected epidermis. Expression of a single viral early protein, HPV16 E6, in KC reduces levels of cell surface E-cadherin thereby interfering with E-cadherin-mediated adhesion. Through this pathway, E6 expression in HPV16-infected KC may limit presentation of viral antigens by LC to the immune system, thus preventing the initiation of a cell-mediated immune response and promoting survival of the virus.

Hypoxia-inducible erythropoietin signaling in squamous dysplasia and squamous cell carcinoma of the uterine cervix and its potential role in cervical carcinogenesis and tumor progression

Tissue hypoxia is a characteristic property of cervical cancers that makes tumors resistant to chemo- and radiation therapy. Erythropoietin (Epo) is a hypoxia-inducible stimulator of erythropoiesis. Acting via its receptor (EpoR), Epo up-regulates bcl-2 and inhibits apoptosis of erythroid cells and rescues neurons from hypoxic damage. In addition to human papillomavirus infection, increased bcl-2 expression and decreased apoptosis are thought to play a role in the progression of cervical neoplasia. Using reverse transcriptase-polymerase chain reaction and Western blotting we showed that HeLa and SiHa cervical carcinoma cells and human cervical carcinomas express EpoR, and that hypoxia enhances EpoR expression. Exogenous Epo stimulated tyrosine phosphorylation and inhibited the cytotoxic effect of cisplatin in HeLa cervical carcinoma cells. Using immunohistochemistry, we examined the expression of Epo, EpoR, p16, hypoxia-inducible factor (HIF)-1alpha, and bcl-2 in benign and dysplastic cervical squamous epithelia and invasive squamous cell carcinomas (ISCCs). EpoR expression in benign epithelia was confined to the basal cell layers, whereas in dysplasias it increasingly appeared in more superficial cell layers and showed a significant correlation with severity of dysplasia. Diffuse EpoR expression was found in all ISCCs. Expression of Epo and HIF-1alpha was increased in dysplasias compared to benign epithelia. Focal Epo and HIF-1alpha expression was seen near necrotic areas in ISCCs, and showed correlation in their spatial distribution. Significant correlation was found between expression of EpoR, and p16 and bcl-2 in benign and dysplastic squamous epithelia. Our results suggest that increased expression of Epo and EpoR may play a significant role in cervical carcinogenesis and tumor progression. Hypoxia-inducible Epo signaling may play a significant role in the aggressive behavior and treatment resistance of hypoxic cervical cancers.

Human papillomavirus and cervical cancer: not just a sexually transmitted disease

The human papillomavirus (HPV) is the cause of virtually all cancers of the cervix, the fourth most common cancer in women in the United States. HPV is sexually transmitted, and the lifetime risk of contracting the virus is estimated to be 75%-90%. New methods of detecting HPV infection and cellular changes (dysplasia) caused by HPV can greatly reduce the mortality associated with this virus. More than 100 types of HPV exist and may be classified as low-, intermediate-, or high-risk in terms of causing cancer. The virus can cause genital warts, subclinical dysplasia, and cancer. Nurses play an important role in educating patients regarding HPV and preventive measures as well as in screening and treatment. Most women diagnosed with HPV need emotional support and factual information provided in a supportive, nonjudgmental manner. Nurses can meet this challenge and make a difference in reducing the incidence and mortality of cervical cancer.

HPV 16 detection in cervical lesions, physical state of viral DNA and changes in p53 gene

CONTEXT

Persistent infection with high risk human papillomavirus (HPV) has been linked to cervical carcinoma. Integration of viral DNA into host cell DNA is essential for this cancer development, promoting disruption of the HPV E2 gene, thus leading to unregulated increases in E6 and E7 proteins and inactivating the products of p53 and Rb tumor suppressor genes.

OBJECTIVE

To investigate HPV 16 infection in cervical lesions, physical state of viral DNA and p53 gene alterations in a group of women attending a public health service.

DESIGN

Prospective, non-controlled, transversal study.

SETTING

Gynecological clinic of the School of Medicine, Universidade Federal Fluminense.

SAMPLE

43 consecutive patients with cervical lesions referred to our service.

MAIN MEASUREMENTS

Cases were classified via cytology/histology as normal, HPV infection, condyloma, low-grade squamous intraepithelial lesion (LSIL), high-grade squamous intraepithelial lesion (HSIL) and carcinoma. HPV infection was studied via polymerase chain reaction (PCR) using two PCR primer sets, to determine DNA integration. p53 gene changes were investigated by single-strand conformation polymorphism (SSCP) analysis.

RESULTS

One normal case, 7 HPV infections, 6 condylomas, 7 LSIL, 14 HSIL and 8 cancers were found, with 95% positive for HPV genome when tested using both L1 and E6 primers. HPV 16 was most prevalent (73.1%). HPV 16 DNA was integrated within the host genome in 3 LSIL. One LSIL progressed to HSIL by 13 months after first diagnosis. Among HPV 16-positive HSIL cases, 50% contained integrated viral DNA. HPV 16 E2 gene disruption was seen in 7 cancers (87.5%). Only smal-cell carcinoma showed intact HPV 16 E2 gene. Abnormal p53 bands detected by PCR/SSCP were observed in 4 cases: 2 squamous carcinoma with parametrium (exon 8) and two cervical intraepithelial neoplasia (CIN) III (exons 5 and 7). All cases presented HPV 16 E2 gene loss.

CONCLUSIONS

The sample had a high rate of high-risk HPV detected in benign and malignant lesions; high cervical cancer burden; HPV 16 DNA integration in all except one case of cancer; p53 gene changes in CIN III and in invasive cancer cases associated with DNA integration.

High risk HPV types in southern Iranian patients with cervical cancer

This study was undertaken to assess the rate of HPV infection in cervical carcinoma among southern Iranian patients. 101 archival cervical carcinoma tissue samples of a 10 year period were studied for the presence of HPV DNA in southern Iran by a polymerase chain reaction method. In addition, the presence of high risk HPV-16 and HPV-18 genotypes was investigated. In total, 88 (87.1%) of the samples were HPV DNA positive, of which 83 were squamous cell carcinomas and 5 were adenocarcinomas. HPV-16 genotype was detected in 26.7% of HPV positive cervical carcinomas; however, none of the samples were positive for the existence of HPV-18 genotype. Collectively, these results suggest that HPV-16 and HPV-18 are not the frequent high risk HPV types in our patients and circulating HPV types in southern Iranian population are different from many other populations.

p53 in surgically treated and pathologically staged cervical cancer: correlation with local tumor progression, but not with lymphatic spread

There is only limited information about the prognostic value of p53 immunostaining in cervical cancer. The purpose of this study was to assess the clinical significance of p53 and prognosis in operatively treated cervical carcinoma. A hundred and fourteen primary surgically treated cervical carcinomas (CX) were obtained from the so called Wertheim Archive in the Department of Obstetrics and Gynecology at the University of Leipzig. These included 105 squamous cell cancer (SCC) and nine adenocarcinomas (AC). No cases received neoadjuvant therapy. For immunohistochemical analysis, the cases were tested with the monoclonal antibody DO-7 (DAKO Diagnostics, Denmark). Two hundred tumor cell nuclei were counted for positive nuclear immunostaining, regardless of staining intensity. Cases were stated as positive when a minimum of 10% nuclei showed positive staining. Fresh frozen tissue was available from 21 CX for p53-mutation analysis (exons 4-9) using PCR-based amplification and SSCP-analysis. Of the squamous cell cancers (SCC), 63.8% showed positive nuclear p53-immunostaining; adenocarcinomas (AC) were completely negative (P = 0.0000, Chi2-test). Stage-by-stage analysis revealed no differences in p53-expression. However, combining pT1b- and pT2-cases, the difference in positive immunostaining reached statistical significance (44.4% vs. 71.7%; P = 0.007). There were no differences in p53-reactivity regarding the presence of pelvic lymph node metastases, tumor grading, relapse-free survival and tumor recurrence. In addition, only 5% of CX with positive p53-immunostaining showed genomic alterations in mutational analysis. p53-immunoreactivity showed significant correlation with local tumor progression but not with lymphatic spread, lacking any prognostic impact in surgically treated cervical cancer. There is no correlation of p53-immunostaining with the occurrence of p53-gene mutations in cervical cancer.