Development Of Squamous Intraepithelial Lesions Research Articles

Telomere Length, Telomerase Activity, and Vaginal Microbiome in Patients with HPV-Related Precancerous Lesions.

Persistent high-risk human papillomaviruses (HR HPVs) infection leads to the development of squamous intraepithelial lesions in cervical cells that may lead to cancer. The telomere length, telomerase activity, and species composition of the vaginal microbiome may influence the dynamic of changes and the process of carcinogenesis. In the present study, we analyze relative telomere length (RTL), relative hTERT expression (gene for the telomerase component-reverse transcriptase) in cervical smear cells and vaginal microbiomes. Total RNA and DNA were isolated from tissue samples of 109 patients from the following groups: control, carrier, low-grade or high-grade squamous intraepithelial lesion (L SIL and H SIL, respectively), and cancer. The quantitative PCR method was used to measure telomere length and telomerase expression. Vaginal microbiome bacteria were divided into community state types using morphotype criteria. Significant differences between histopathology groups were confirmed for both relative telomere length and relative hTERT expression (p < 0.001 and p = 0.001, respectively). A significant difference in RTL was identified between carriers and H SIL (p adj < 0.001) groups, as well as between carriers and L SIL groups (p adj = 0.048). In both cases, RTL was lower among carriers. The highest relative hTERT expression level was recorded in the H SIL group, and the highest relative hTERT expression level was recorded between carriers and the H SIL group (p adj < 0.001). A correlation between genotype and biocenosis was identified for genotype 16+A (p < 0.001). The results suggest that identification of HPV infection, telomere length assessment, and hTERT expression measurement together may be more predictive than each of these analyses performed separately.

Microbiome markers in HPV-positive and HPV-negative women of reproductive age with ASCUS and SIL determined by V4 region of 16S rRNA gene sequencing.

Human papilloma virus (HPV) is the most common sexually transmitted infection worldwide. Cervicovaginal microbiota plays an important role in HPV infection and is associated with the development of squamous intraepithelial lesions (SIL). The natural history of cervical cancer involves reversible changes in the cervical tissue from a normal state, in which no neoplastic changes are detected in the squamous epithelium, to varying states of cellular abnormalities that ultimately lead to cervical cancer. Low-grade SIL (LSIL), like another cytological category - atypical squamous cells of undetermined significance (ASCUS), may progress to high-grade SIL (HSIL) and invasive cervical cancer or may regress to a normal state. In this work, we studied cervical canal microbiome in 165 HPV-positive and HPV-negative women of a reproductive age with ASCUS [HPV(+) n = 29; HPV(-) n = 11], LSIL [HPV(+) n = 32; HPV(-) n = 25], HSIL [HPV(+) n = 46], and the control group with negative for intraepithelial lesion malignancy (NILM) [HPV(-) n = 22]. HPV16 is the most prevalent HPV type. We have not found any differences between diversity in studied groups, but several genus [like Prevotella (p-value = 0.026), Gardnerella (p-value = 0.003), Fannyhessea (p-value = 0.024)] more often occurred in HSIL group compared by NILM or LSIL regardless of HPV. We have found statistically significant difference in occurrence or proportion of bacterial genus in studied groups. We also identified that increasing of the ratio of Lactobacillus iners or age of patient lead to higher chance to HSIL, while increasing of the ratio of Lactobacillus crispatus lead to higher chance to LSIL. Patients with a moderate dysbiosis equally often had either of three types of vaginal microbial communities (CST, Community State Type) with the prevalence of Lactobacillus crispatus (CST I), Lactobacillus gasseri (CST II), and Lactobacillus iners (CST III); whereas severe dysbiosis is linked with CST IV involving the microorganisms genera associated with bacterial vaginosis and aerobic vaginitis: Gardnerella, Fannyhessea, Dialister, Sneathia, Anaerococcus, Megasphaera, Prevotella, Finegoldia, Peptoniphilus, Porphyromonas, Parvimonas, and Streptococcus.

Oxysterol 25-hydroxycholesterol activation of ferritinophagy inhibits the development of squamous intraepithelial lesion of cervix in HPV-positive patients

Squamous intraepithelial lesion of cervix (SIL) in human papillomavirus (HPV)-positive patient often undergoes a silent and long-course development, and most of them with high-grade transit to cervical squamous cell carcinoma (CSCC). The oxysterol 25-hydroxycholesterol (25-HC) is associated with HPV inhibition, autophagy and cholesterol synthesis, however, its function in this long process of SIL development remain unclear. In this study, we demonstrate that 25-HC generation is inhibited through HSIL-to-CSCC transition. The 25-HC activates ferritinophagy in the early stage of SIL, promoting the vulnerability of HSILs to ferroptosis. Therefore, maintaining 25-HC level is crucial for suppressing HSIL progression and holds promise for developing novel clinical therapies for CSCC.

A study on the correlation between the prognosis of HPV infection and lesion recurrence after cervical conization.

Persistent human papillomavirus infection is an important factor in the development of cervical cancer, which is usually a long process evolving from the development of squamous intraepithelial lesions (SIL), also referred to as cervical intraepithelial neoplasia (CIN). Local treatment of advanced squamous intraepithelial lesions, also regarded as High-Grade Squamous Intraepithelial Lesion, may be effective in preventing cancer. To promptly identify high-risk patients with a tendency to recurrence. We retrospectively analyzed the clinical data of 300 patients with high-grade squamous intraepithelial lesions of the cervix admitted to the Second Affiliated Hospital of Dalian Medical University from 2019 to 2020 to investigate the relationship between recurrence of cervical lesions and postoperative regression of HPV infection, as well as other related risk factors. We found that the HPV-negative rates were 81.81, 85.71, and 90.91% at 6, 12, and 24 months, respectively, and the average lesion recurrence rate was 8.16%, with a median time to recurrence of 14 months in patients undergoing CKC for HSIL. The risk of cervical squamous intraepithelial lesions was highest in patients with HPV16. Patients over 61 years of age had the lowest postoperative HPV-negative rate. The conversion rate was significantly lower in patients with multiple HPV genotypes than in those with single HPV infection (p < 0.05). The probability of recurrence was higher in patients with the same HPV infection genotype before and after surgery than in patients with different infection genotypes before and after surgery (p < 0.05). Combined with the literature review, we believe that patients aged ≥50 years, with ≥3 pregnancies and births, a history of smoking, and consistent genotypes of preoperative and postoperative HPV infection in cervical conization have more HPV re-infection or persistent infection, and that these factors may be high-risk factors for lesion recurrence. For patients with possible potential high-risk factors, we need to carry out individualized follow-up and focused management, take timely and effective management measures, optimize the treatment plan, reduce the recurrence rate, prevent HSIL and cervical cancer, improve the quality of patient's survival, and improve the prognosis.

Cervical Cytology Findings in Renal Transplant Patients and Comparison of These Findings with Normal Population

Long-term immunosuppressive therapy increases the likelihood of renal transplant patients developing cervical cancer. We aimed to analyze the results of cervical cytology in renal transplant patients, compare these findings to those of the normal population, and determine the risk factors linked to the development of squamous intraepithelial lesions. Our analysis involved a retrospective study of hospital records from January 2000 to April 2018, encompassing 140 female renal transplant patients. A control group of 280 women with normal health status was selected and matched based on age and the cervical cytology procedure. The cervical cytology findings of the patients were re-evaluated using the Bethesda 2014 criteria. Of the total of 420 patients, 37 patients had epithelial cell abnormalities; including 32 (86.5%) patients in the renal transplant group and 5 (13.5%) control group (p ≤ 0.001). Sixty-two patients had infections; including 44 (71%) patients in the renal transplant group and 18 (29%) control group (p ≤ 0.001). We revealed that the development of squamous intraepithelial lesions was associated with factors such as having an immunologic disease as the primary renal disease, undergoing re-transplantation, and the presence of acute rejection (p ≤ 0.05). Cervical cytology screening plays a crucial role in detecting preinvasive lesions. The incidence of epithelial cell abnormalities is significantly higher in renal transplant patients compared to the normal population. Regular cervical cytology follow-up is vital for the early detection and prevention of cervical cancer progression in transplant recipients.

FDA-APPROVED MOLECULAR TESTS USED TO DEFINE HUMAN PAPILLOMAVIRUS (HPV) INFECTIONS WHICH CAUSE CERVIX CANCER

Human papillomavirus (HPV) is a non-enveloped, commonly sexually transmitted virus with icosahedral symmetry and double-stranded circular DNA. Its genome, which is about 8 kb in size, encodes early genes (E1-8) and two late structural capsid genes (L1 and L2). Among the genes that play a role in viral pathogenesis, L1, E6, and E7 genes frequently exist. The E6 and E7 viral genes have a significant role in apoptosis inhibition, viral spread, development of squamous intraepithelial lesion (SIL), cell immortalization, neoplastic transformation, and invasive cancer.&#x0D; Demonstration of the relationship between cervical cancer and HPV infections has led to increased interest in this subject and the classification of some HPV genotypes in the high-risk group (HR-HPV) for cervical cancer. Numerous commercial molecular tests have been developed for the identification of HPV genotypes involving different approaches. HPV molecular tests approved by the US Food and Drug Administration (FDA) include Hybrid Capture® 2 (HC2), Cervista™, cobas®, Aptima®, and BD Onclarity™. This article reviews the methodologies, limitations, and commonalities of five FDA-approved tests. The HC2 and Cervista™ tests use non-PCR-based signal amplification methods, while the cobas® and BD Onclarity™ tests use PCR-based target amplification methods. On the other hand, the Aptima® test uses the mRNA transcriptional mediated amplification (TMA) method.&#x0D; Each of these methods used in the diagnosis and follow-up of HPV has its strengths and weaknesses. These HPV molecular tests have high sensitivity and specificity. They are also more automated and repeatable than cytological methods. In addition to these advantages, there are also several limitations. Because of these limitations, molecular tests are no more perfect than cytological tests. This situation shows that these tests should not be used alone in the evaluation of HPV infections and cancer identification. On the contrary, HPV test results should be correlated with cytology or biopsy findings.

Significant decrease of a master regulator of genes (REST/NRSF) in high-grade squamous intraepithelial lesion and cervical cancer

BackgroundThe repressor element 1-silencing transcription factor (REST) is a regulator of gene expression, and the Ras association domain family member 1 A (RASSF1A) is an important tumor suppressor gene involved in cancer development. Although extensive characterization of the roles of REST and RASSF1A in cancer development have been reported in cellular models, the link between them and their possible role in the development of squamous intraepithelial lesions (SIL) and squamous cell carcinoma (SCC) of the cervix have not been explored. The aim of this study was to evaluate the expression of REST and RASSF1A in cervical cytological and histological samples from patients diagnosed with SIL or SCC and in CC-derived cell lines. MethodsWe analyzed the expression of REST and RASSF1A by immunocyto/histochemistry in cervical samples from patients (n = 271) and in cancer cell lines. Data analyses were performed using the Kruskal–Wallis test and generalized linear models. ResultsWe identified binding sites for REST in RASSF1A and observed a significant reduction in REST and RASSF1A nuclear expression in samples from patients with high-grade SIL (HSIL) and SCC. For REST, we observed an average decrease of 334 and 423 r.u.d. for HSIL (n = 21) and SCC (n = 18) compared with non-LSIL (n = 72), whereas for RASSF1A, this decrease was 126 and 217 r.u.d., respectively (p < 0.001). ConclusionOur results provide evidence of the altered expression of REST and RASSF1A in SIL and SCC, with a significant decrease in HSIL, SCC, and SCC-derived cell lines; findings that can contribute to the diagnosis, prognosis, and post-treatment follow-up of patients diagnosed with SIL or SCC.

Telomere length in leukocytes and cervical smears of women with high-risk human papillomavirus (HR HPV) infection

ObjectivePersistent high-risk HPV (HR HPV) infection leads to the development of squamous intraepithelial lesions, which in turn may progress to cervical cancer. Telomere elongation or shortening may indicate a carcinogenesis process. In the present study, we analyzed telomere length from blood and cervical smears of women without and with high-risk HPV infection. Materials and methodsTelomere length was quantified by real-time PCR in blood and cervical smears from 48 women with high-risk HPV infection and HGSIL or LGSIL, 29 women HR-HPV positive without SIL, and 11 HPV-negative women. ResultsNo correlation was found between age and telomere length in blood and cervical smears. Women with high-risk HPV infection had shorter telomeres in cervical smears, but not in blood compared to the control group. ConclusionThese findings suggest that telomere shortening occurs in cervical cells of women with HR HPV infection both with LGSIL and HGSIL and may indicate the onset of carcinogenesis. In turn, there is no correlation between leukocyte telomere length and cervical cancer risk in women with HR HPV infection.

Awareness, Knowledge and Attitudes Towards Cervical Cancer Amongst HIV-Positive Women Receiving Care in a Tertiary Hospital in Nigeria

The incidence of cervical cancer (CC) in the sub-Saharan Africa region, where Nigeria is located, is amongst the highest in the world; it is estimated that 70,722 new cases of invasive cervical cancer occur annually in sub-Saharan Africa. Immunosuppression, especially due to human immunodeficiency virus (HIV) infection, is a predisposing factor for persistent infection with high-risk human papilloma virus (HR-HPV) and the development of squamous intraepithelial lesions. Four hundred and fifty women who attended the HIV clinic at the Nnamdi Azikiwe University Teaching Hospital, Nnewi, and who consented to participate in the study were randomly selected. They were given self-administered questionnaires which sought to determine their awareness and knowledge of cervical cancer and attitudes towards cervical cancer screening and prevention. The media 23% (n=103) was the most common source of information amongst respondents who had heard about cervical cancer. For all the women surveyed, the average percentage knowledge was 9.95%. Having attitude scores greater than or equal to the mean attitude score of 55.16% was regarded as having a positive attitude while a score lower than that was regarded as negative attitude. About 43.5% (n=195) respondents had a positive attitude towards cervical cancer screening and prevention. Cervical cancer awareness and knowledge amongst women attending the HIV clinic in the Nnamdi Azikiwe University Teaching Hospital, Nnewi, were very poor. Their attitude towards cervical cancer screening practices and prevention was also very poor.

Human Papillomavirus and Pap Smear

High-risk human papillomavirus (HPV) infection and viral persistence is a major risk factor in the development of squamous intraepithelial lesions and invasive carcinoma of the cervix. In the United States, deaths due to squamous cell carcinoma of the cervix have fallen by 75% since the 1960s because of Papanicolaou (Pap) smear screening. However, the traditional Pap had a sensitivity of about 70% for detecting clinically significant precancerous lesions and cancer because of sampling and interpretive errors. The introduction of 2 liquid-based Pap smear collection systems in the 1990s, the use of HPV testing as a triage and co-testing with Pap smear, and the introduction of 2 automated screening devices have had a significant impact on improving the detection of such precancerous lesions. This review provides an analysis of the changes in Pap smear collection, improvements in screening, the evolutionary changes of high-risk HPV testing, reporting terminology of Pap smears, and clinical management guidelines. The future impact of 2 prophylactic HPV vaccines on the incidence of cervical carcinoma is also discussed. This article also discusses alternatives such as primary screening for high-risk HPV testing with visual inspection for cervical cancer detection used in resource-poor settings with a high incidence of cervical cancer.

Risk factors for squamous intraepithelial lesions in systemic lupus erythematosus: A prospective cohort study

We undertook a prospective cohort study to ascertain the risk factors for the development of squamous intraepithelial lesions (SIL) in patients with systemic lupus erythematosus (SLE). One hundred thirty-seven SLE patients with a normal Papanicolaou (Pap) smear at baseline were evaluated at 6-month intervals for up to 3 years. At each visit, a Pap smear, human papillomavirus (HPV) DNA test, and clinical assessment were performed. Among the 137 patients, there were 12 incident cases (8.8%) of SIL over a median followup duration of 30.7 months (interquartile range 25.5-31.7). Among the 30 patients with HPV infection detectable by DNA testing at baseline, 9 (30%) developed SIL. The independent risk factors for the incident SIL in this group of SLE patients included the use of cyclophosphamide (CYC) ever (odds ratio [OR] 5.6, 95% confidence interval [95% CI] 1.1-29.3; P=0.041) and persistent high-risk HPV infection (OR 26.9, 95% CI 3.2-222.3; P=0.002). The use of baseline HPV testing has a higher sensitivity than abnormal cytology (defined as atypical squamous cells of undetermined significance; 47.7% versus 33.3%) in predicting the development of SIL. Independent risk factors associated with the development of SIL in SLE patients included persistent high-risk HPV infection and the use of CYC. Low-risk patients who receive negative test results on both cervical cytology screening and HPV DNA testing may not need to be rescreened within 3 years.

Incidence of cervical disease associated to HPV in human immunodeficiency infected women under highly active antiretroviral therapy

BackgroundWomen infected with human immunodeficiency virus (HIV) may be at higher risk of developing cervical cancer than non infected women. In a pilot study, we assessed the relationships among cervical cytology abnormalities associated to Human Papillomavirus (HPV), HIV infection and Highly Active Antiretroviral Therapy (HAART) on the development of Squamous Intraepithelial lesions (SILs). Out of the 70 HIV infected women from Douala -Cameroon (Central Africa) that we included in the study, half (35) were under HAART. After obtaining information related to their lifestyle and sexual behaviour, cervicovaginal samples for Pap smears and venous blood for CD4 count were collected and further divided into two groups based upon the presence or absence of cervical cytology abnormalities i.e. those with normal cervical cytology and those with low and high Squamous Intraepithelial lesions (LSIL, HSIL).ResultsAssessment was done according to current antiretroviral regimens available nationwide and CD4 count. It was revealed that 44.3% of HIV-infected women had normal cytology. The overall prevalence of LSIL and HSIL associated to HPV in the studied groups was 24.3% (17/70) and 31.4% (22/70) respectively. Among the 22 HSIL-positive women, 63.6% (14/22) were not on antiretroviral therapy, while 36.4% (8/22) were under HAART. HIV infected women under HAART with positive HSIL, showed a median CD4+ T cell count of 253.7 +/- 31.7 higher than those without therapy (164.7 +/- 26.1). The incidence of HSIL related to HPV infection within the study group independently of HAART initiation was high.ConclusionThese results suggest the need for extension and expansion of the current study in order to evaluate the incidence of HPV infection and cervical cancer among HIV-infected and non HIV- infected women in Cameroon.

Vitamin A and cervical squamous intraepithelial lesions

Sir, The vast majority of women who come into contact with Human Papilloma Virus (HPV) do not develop any cervical lesions 1. Among those who do, few still present with a high-grade squamous intraepithelial lesion (HSIL) of the cervix. Brazil has a high incidence of cervical cancer, mostly in the northeast region where poverty and malnutrition rates are high 2. Previous studies have shown a high prevalence of low vitamin A levels in this population, which has been considered a public health problem 3. The progression of the disease may be multifactorial, presenting many co-factors, which associated with HPV infection could lead to an increased risk of developing HSIL. Nutritional factors are gradually taking on an important role in understanding the pathophysiology of HPV infection and may help to explain the mechanisms that result in the progression of intraepithelial lesions in some women 1. Although still uncertain, the hypothesis has been advanced that an adequate intake of vitamin A could protect individuals against the development of squamous intraepithelial lesions. Experiments in animals have shown that vitamin A deficiency predisposes to the development of these lesions 4. The deficit of retinoids in turn, was associated with an increased risk of gastrointestinal tract, genito-urinary and skin cancer 5. We have carried out a cross-sectional pilot study to assess the levels of Vitamin A by means of the Bessey–Lowrey method, modified by Araujo & Flores 3 in 40 women aged between 14 and 48 years who had colposcopy directed biopsy of the cervix in the Cervical Pathology and Colposcopy Service in the Federal University of Ceara (UFC) in Fortaleza, Brazil, between July 2004 and July 2005. Of these women, 17 (42.5%) had negative results for squamous intraepithelial lesions (SILs). In 23 (57.5%) cases, the histological diagnosis pointed to SIL, and 18 (45%) had low-grade (LSIL), while five (12.5%) had high grade (HSIL). The serum levels of vitamin A ranged from 9.1 g/dl to 108.4 mg/dl. Vitamin A levels below 20 μg/dl (low) were found in only 1/17 (6%) women without a cervical lesion, but 4/18 (22%) among those with LSIL and 5/5 (100%) of HSIL. There was no significant difference between serum vitamin A levels for women with negative biopsies and with low-grade SIL, but there may be still lower levels in women with high-grade lesions. Vitamin A can perhaps be an important co-factor in the development of SILs, but more comprehensive studies and intervention trials with vitamin supplementation are necessary to evaluate this.

Increased Sensitivity of Radiated Murine Cervical Cancer Tumors to E7 Subunit Vaccine–driven CTL-mediated Killing Induces Synergistic Anti-tumor Activity

The development of therapeutic vaccines has important implications for the treatment of cancer patients. Here we investigate whether human papillomavirus (HPV) E7 subunit vaccines can enhance tumor radioresponse using an established cervical cancer animal model. Radiation plus E7 subunit vaccines improved complete response, cure, and recurrence rates of tumors dramatically compared with single therapy alone. In particular, both components of the E7 subunit vaccines (E7 protein and CpG-oligodeoxynucleotide) were required for the induction of antigen (Ag)-specific cytotoxic T-lymphocyte (CTL) responses and for therapeutic synergy with radiotherapy. Moreover, with combined therapy the radiation dose could be reduced by 16 Gy to achieve an equivalent anti-tumor efficacy to radiation treatment alone. This therapeutic synergy was found to be mediated by CD8(+) CTLs and was concomitant with histological changes (presence of apoptotic bodies and multinucleated giant cells; heavy infiltration of lymphocytes), as determined by in vivo T-cell depletion and histological analysis. Finally, phenotypic changes of radiated tumors and their increased sensitivity to CTL-mediated killing appeared to be responsible for therapeutic synergy. These results show that E7 subunit vaccines act as a potent enhancer of tumor radioresponse and that this is mediated by increased sensitivity of radiated tumors to CTL-mediated killing. This study further suggests that E7-targeted therapeutic vaccines have the potential to improve radiotherapy in patients with cervical cancer.

Cell cycle and/or proliferation markers: what is the best method to discriminate cervical high-grade lesions?

The aim of this study on a series of biopsies diagnosed as normal, metaplastic, low-grade squamous intraepithelial lesions (LSILs), and high-grade squamous intraepithelial lesions (HSILs) was dual: to determine the chronology of cell cycle and proliferation abnormalities after human papillomavirus infection during the development of squamous intraepithelial lesions and to determine the best diagnostic indicator(s) linked to the appearance of an HSIL. Ninety-nine cervical biopsies, 18 normal, 9 with metaplastic changes, 29 LSIL, and 43 HSIL (23 cervical intraepithelial neoplasia 2 and 20 cervical intraepithelial neoplasia 3), were analyzed by image cytometry for DNA ploidy and p16INK4A determination, AgNOR counting, MIB-1, and ICBP90 immunostaining quantification. The human papillomavirus status had been previously determined on corresponding cytological smears with the Hybrid Capture II test. Suspect DNA profile and p16INK4A staining were the first significant events that preceded the increase of cell proliferation. Indeed, these markers were the best tests for the detection of a lesion, whatever its grade (positive predictive values of 90% and 100%, respectively). The presence of MIB-1- or ICBP90-positive cells in the upper two thirds of the epithelium was a very accurate feature to select HSIL (sensitivity, 100% for MIB-1) but with a low specificity. The sensitivity of a suspect DNA profile associated with a positive MIB-1 or ICPB90 immunostaining for the detection of an HSIL was, respectively, 92.8% and 92.7%; their specificities were 54.2% and 44%; their positive predictive values were 78% and 73%; their negative predictive values were 81.2% and 78.6%; and the global values were 78.8% and 74.3%. Thus, the most accurate test to distinguish an LSIL from an HSIL was the association of a suspect DNA profile and the presence of MIB-1- or ICBP90-positive cells in the upper two thirds of the epithelium.

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Type specific persistence of high risk human papillomavirus (HPV) as indicator of high grade cervical squamous intraepithelial lesions in young women: population based prospective follow up study

Objectives: To investigate the role of human papillomavirus (HPV) in the development of cervical neoplasia in women with no previous cervical cytological abnormalities; whether the presence of virus DNA predicts...

Influence of the mucosal epithelium microenvironment on Langerhans cells: implications for the development of squamous intraepithelial lesions of the cervix.

We have addressed the notion that the initiation and progression of human papillomavirus associated cancer of the uterine cervix are associated with alterations of Langerhans cells (LC) within the mucosal squamous epithelium. Since the transformation zone (TZ) of the cervix is the site where the majority of squamous intraepithelial lesions (SIL) are initiated, in contrast to the exocervix, we decided to investigate the influence of the local microenvironment within the TZ on the function and density of LC. We show that the TZ is associated with a significant reduction in the density of immature LC (CD1a/LAG) compared to the exocervix. In contrast, the development of SILs is attributed with a relative increased density of immature LC, compared to the TZ. Furthermore, we show that this variability in LC density is correlated with a differential expression of TNFalpha and MIP3alpha within the micro-environment of the TZ and SILs. Both TZ and SIL epithelium-derived LC, in the presence of allogeneic PBMC, induced lower levels of proliferation and IL2 production and higher levels of the immunosuppressive cytokine IL10 in comparison to the exocervix. Nevertheless, the epithelium-derived LC in SILs exhibits a reduction in their functional activity, relative to the TZ. Together our studies suggest that the immunosurveillance within the epithelium of the TZ may be intrinsically perturbed due to the altered expression of chemokines/cytokines and the concomitant diminished density of LC. Furthermore, following HPV infection and the development of SILs, the function of LC may be further incapacitated by viral associated mechanisms.

Human papillomavirus variants and squamous neoplasia of the cervix.

Human papillomaviruses (HPVs) play a central role in the aetiology of cervical neoplasia. However, only a small proportion of cervical intraepithelial lesions infected with high-risk HPVs will progress to invasive cervical carcinoma, which indicates the involvement of additional factors. An important emerging viral factor is naturally occurring intratypic sequence variation. Such variation has been used to study the geographical spread of HPVs, but there is increasing evidence that it may be important in determining the risk of development of neoplastic disease. The collected data indicate that different HPV variants have altered biochemical and biological properties and represent an additional risk factor in the development of squamous intraepithelial lesions and invasive carcinoma of the cervix. This may be relevant not only to the biology of HPV infection and its association with squamous neoplasia, but also to the use of HPV typing in clinical practice.

Ultrastructural Localization of Human Papillomavirus Sequences by In Situ Hybridization and Image Analysis

Genital infection caused by human papillomavirus (HPV) is of great sanitary importance because of the role it can play in the development of squamous intraepithelial lesions and carcinomas. Because not all lesions have a malignant transformation, it is important that clinical and biological parameters contributing to the evolution of a specific lesion be determined.We used CaSki cells with 400–600 integrated copies of HPV-16 genome for in situ hybridization (ISH) with electron microscopy (EM) to locate HPV sequences. Three biotinylated DNA probes for HPV types 6/11, 16/18 and 31/ 33/51 were used, and hybrid detection was done with an anti-biotin antibody conjugated with 15 nm gold colloids. Electron microphotographs with positive labeling were studied by image analysis to skeletonize them to highlight the heterochromatin fibers and to determinate the spatial localization of colloidal-gold particles. Electron microscopy and ISH technique revealed 2 different distribution patterns: colloidal-gold particles spread over the whole nuclear surface, individually or in small clusters, and large accumulations with many gold particles in the nuclear periphery, next to the membrane. Image analysis revealed there was a spatial association between the gold particles and heterochromatin fibers in all cases.We believe this association is the consequence of viral genome integration. With these results and knowledge that integration of viral DNA is linked to a worse prognosis, we propose the application of this methodology for the future study of HPV infected biopsies to obtain prognostic information in lesions caused by this virus. (The J Histotechnol 21: 295–298, 1998)