935 resultados para Human papillomavirus


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Abstract Background Invasive cervical cancer is the second most common malignant tumor affecting Brazilian women. Knowledge on Human Papillomavirus (HPV) genotypes in invasive cervical cancer cases is crucial to guide the introduction and further evaluate the impact of new preventive strategies based on HPV. We aimed to provide updated comprehensive data about the HPV types’ distribution in patients with invasive cervical cancer. Methods Fresh tumor tissue samples of histologically confirmed invasive cervical cancer were collected from 175 women attending two cancer reference hospitals from São Paulo State: ICESP and Hospital de Câncer de Barretos. HPV detection and genotyping were performed by the Linear Array HPV Genotyping Test (Roche Molecular Diagnostics, Pleasanton,USA). Results 170 out of 172 valid samples (99%) were HPV DNA positive. The most frequent types were HPV16 (77.6%), HPV18 (12.3%), HPV31 (8.8%), HPV33 (7.1%) and HPV35 (5.9%). Most infections (75%) were caused by individual HPV types. Women with adenocarcinoma were not younger than those with squamous cell carcinoma, as well, as women infected with HPV33 were older than those infected by other HPV types. Some differences between results obtained in the two hospitals were observed: higher overall prevalence of HPV16, absence of single infection by HPV31 and HPV45 was verified in HC-Barretos in comparison to ICESP patients. Conclusions To our knowledge, this is one of the largest studies made with fresh tumor tissues of invasive cervical cancer cases in Brazil. This study depicted a distinct HPV genotype distribution between two centers that may reflect the local epidemiology of HPV transmission among these populations. Due to the impact of these findings on cervical cancer preventive strategies, extension of this investigation to routine screening populations is warranted.

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Abstract Background Immunological alterations are implicated in the increased prevalence of high-grade squamous intraepithelial lesions (HG-SIL) and persistent human papillomavirus (HPV) infection. This study evaluated the expression of CD4, CD8, CD25 (IL-2Rα) and CD28 antigens from SIL biopsies, stratified by HIV status and HPV-type. Biopsies specimens from 82 (35 HIV+) women with a normal cervix, low-grade (LG-SIL) or high-grade lesions (HG-SIL) were studied. CD molecule expression was evaluated by immunohistochemistry and HPV detection/typing performed using PCR techniques. Results CD4 stromal staining was increased in patients with HPV18. Women with HPV16 infection showed decreased: a) CD8 and CD25 stromal staining, b) CD25 staining in LG-SIL epithelium and in HG-SIL stroma. In HIV- women samples, CD28 epithelial staining and CD8 stromal staining surrounding metaplastic epithelium were less intense and even absent, as compared to HIV+ women. Both epithelial and stromal CD8 staining was more intense in the HG-SIL/HIV+ group than in the HG-SIL/HIV- group. Positive correlations were observed between CD4/CD25, CD4/CD28 and CD25/CD28 in the stroma and CD25/CD28 in the epithelium. Conclusion HIV status and HPV-type may influence the lymphomononuclear cell profile present in the spectrum of cervical lesions. The knowledge of the infiltrating cell profile in cervical tumours may help the development of specific anti-tumoural strategies.

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Human Papillomavirus (HPV) is the cause of cervical cancers (among these, adenocarcinoma, AdCa) and is associated to a subgroup of oropharyngeal carcinomas (OPSCCs). Even if the risk for cancer development is linked to the infection by some viral genotypes, mainly HPV16 and 18, viral DNA alone seems not to be sufficient for diagnosis. Moreover, the role of the virus in OPSCCs has not been totally clarified yet. In the first part of the thesis, the performances concerning viral genotyping in clinical cervical samples of a new pyrosequencing-based test and a well-known hybridization-based assay have been compared. Similar results between the methods have been obtained. However, the former showed advantages in detecting intratype variants, higher specificity and a broader spectrum of detectable HPV types. The second part deals with the evaluation of virological markers (genotyping, viral oncoproteins expression, viral load, physical state and CpG methylation of HPV16 genome) in the diagnosis/prognosis of cervical AdCa and HPV-associated OPSCCs. HPV16 has been confirmed the most prevalent genotype in both the populations. Interestingly, the mean methylation frequency of viral DNA at the early promoter showed the tendency to be associated to invasion for cervical AdCa and to a worse prognosis for OPSCCs, suggesting a promising role as diagnostic/prognostic biomarker. The experiments of the third part were performed at the DKFZ in Heidelberg (Germany) and dealt with the analysis of the response to IFN-k transfection in HPV16-positive cervical cancer and head&neck carcinoma cell lines to evaluate its potential role as new treatment. After 24h, we observed increased IFN-b expression which lead to the up-regulation of genes involved in the antigens presentation pathway (MHC class I and immunoproteasome) and antiviral response as well, in particular in cervical cancer cell lines. This fact suggested also the presence of different HPV-mediated carcinogenic pathways between the two anatomical districts.

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There are controversial data on the meaning of viral induction of breast cancer. The aim of this study was to investigate the presence of human papillomavirus (HPV) DNA in patients with breast carcinoma and the correlation of viral infection with disease outcome. Paraffin-embedded sections from 81 patients with breast cancer were analyzed for HPV DNA by polymerase chain reaction (PCR) using the SPF1/2 primers covering about 40 different low-, intermediate- and high-risk types. We found all samples were negative for HPV DNA. Our analysis could not support a role of HPV in breast carcinoma. Controversial published data indicate a need for further, larger epidemiologic studies.

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PURPOSE: Integration of high-risk papillomavirus DNA has been considered an important step in oncogenic progression to cervical carcinoma. Disruption of the human papillomavirus (HPV) genome within the E2 gene is frequently a consequence. This study investigated the influence of episomal viral DNA on outcome in patients with advanced cervical cancer treated with primary radiotherapy. METHODS AND MATERIALS: Paraffin-embedded biopsies of 82 women with locally advanced cervical cancer could be analyzed for HPV infection by multiplex polymerase chain reaction (PCR) by use of SPF1/2 primers. E2-gene intactness of HPV-16-positive samples was analyzed in 3 separate amplification reactions by use of the E2A, E2B, E2C primers. Statistical analyses (Kaplan-Meier method; log-rank test) were performed for overall survival (OS), disease-free survival (DFS), local progression-free survival (LPFS), and distant metastases-free survival (DMFS). RESULTS: Sixty-one (75%) of 82 carcinomas were HPV positive, 44 of them for HPV-16 (72%). Seventeen of the 44 HPV-16-positive tumors (39%) had an intact E2 gene. Patients with a HPV-16-positive tumor and an intact E2 gene showed a trend for a better DFS (58% vs. 38%, p = 0.06) compared with those with a disrupted E2 gene. A nonsignificant difference occurred regarding OS (87% vs. 66%, p = 0.16) and DMFS (57% vs. 48%, p = 0.15). CONCLUSION: E2-gene status may be a promising new target, but more studies are required to elucidate the effect of the viral E2 gene on outcome after radiotherapy in HPV-positive tumors.

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BACKGROUND Cytology is an excellent method with which to diagnose preinvasive lesions of the uterine cervix, but it suffers from limited specificity for clinically significant lesions. Supplementary methods might predict the natural course of the detected lesions. The objective of the current study was to test whether a multicolor fluorescence in situ hybridization (FISH) assay might help to stratify abnormal results of Papanicolaou tests. METHODS A total of 219 liquid-based cytology specimens of low-grade squamous intraepithelial lesions (LSIL), 49 atypical squamous cells of undetermined significance (ASCUS) specimens, 52 high-grade squamous intraepithelial lesion (HSIL) specimens, and 50 normal samples were assessed by FISH with probes for the human papillomavirus (HPV), MYC, and telomerase RNA component (TERC). Subtyping of HPV by polymerase chain reaction (PCR) was performed in a subset of cases (n=206). RESULTS There was a significant correlation found between HPV detection by FISH and PCR (P<.0001). In patients with LSILs, the presence of HPV detected by FISH was significantly associated with disease progression (P<.0001). An increased MYC and/or TERC gene copy number (>2 signals in>10% of cells) prevailed in 43% of ASCUS specimens and was more frequent in HSIL (85%) than in LSIL (33%) (HSIL vs LSIL: P<.0001). Increased TERC gene copy number was significantly correlated with progression of LSIL (P<.01; odds ratio, 7.44; area under the receiver operating characteristic curve, 0.73; positive predictive value, 0.30; negative predictive value, 0.94) CONCLUSIONS: The detection of HPV by FISH analysis is feasible in liquid-based cytology and is significantly correlated with HPV analysis by PCR. The analysis of TERC gene copy number may be useful for risk stratification in patients with LSIL.

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BACKGROUND: Few reports of the utilization of an accurate, cost-effective means for measuring HPV oncogene transcripts have been published. Several papers have reported the use of relative quantitation or more expensive Taqman methods. Here, we report a method of absolute quantitative real-time PCR utilizing SYBR-green fluorescence for the measurement of HPV E7 expression in cervical cytobrush specimens. RESULTS: The construction of a standard curve based on the serial dilution of an E7-containing plasmid was the key for being able to accurately compare measurements between cervical samples. The assay was highly reproducible with an overall coefficient of variation of 10.4%. CONCLUSION: The use of highly reproducible and accurate SYBR-based real-time polymerase chain reaction (PCR) assays instead of performing Taqman-type assays allows low-cost, high-throughput analysis of viral mRNA expression. The development of such assays will help in refining the current screening programs for HPV-related carcinomas.

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Carcinoma of the cervix is causally related to infection with the human papillomavirus (HPV), and T cells play a pivotal role in the immune response of the host to rid itself of HPV infection. Therefore, we assessed the T-cell function of women with HPV-related cervical neoplasia against a superantigen, Staphylococcus enterotoxin B (SEB). Each woman provided a cervical brush specimen for HPV DNA testing and Papanicolaou (Pap) smears for the staging of cervical lesions. They also provided a blood specimen for determination of the ability of CD4(+) T and CD8(+) T cells to synthesize Th1 (interleukin-2 [IL-2], gamma interferon [IFN-gamma], and tumor necrosis factor alpha [TNF-alpha]) and Th2 (IL-10) cytokines in response to activation with SEB. Compared with control subjects with self-attested negative Pap smears, women with high-grade squamous intraepithelial lesions (HSIL) had significantly lower percentages of activated CD4(+) T cells that produced IL-2 (P = 0.045), IFN-gamma (P = 0.040), and TNF-alpha (P = 0.015) and a significantly lower percentage of activated CD8(+) T cells that produced IL-2 (P < 0.01). These data indicate that women with HPV-related cervical HSIL show a decrease in Th1 cytokine production by activated CD4(+) T cells and suggested that compromised T-helper functions may negatively impact the function of cytotoxic CD8(+) T cells.

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OBJECTIVE: We sought to evaluate the performance of the human papillomavirus high-risk DNA test in patients 30 years and older. MATERIALS AND METHODS: Screening (n=835) and diagnosis (n=518) groups were defined based on prior Papanicolaou smear results as part of a clinical trial for cervical cancer detection. We compared the Hybrid Capture II (HCII) test result with the worst histologic report. We used cervical intraepithelial neoplasia (CIN) 2/3 or worse as the reference of disease. We calculated sensitivities, specificities, positive and negative likelihood ratios (LR+ and LR-), receiver operating characteristic (ROC) curves, and areas under the ROC curves for the HCII test. We also considered alternative strategies, including Papanicolaou smear, a combination of Papanicolaou smear and the HCII test, a sequence of Papanicolaou smear followed by the HCII test, and a sequence of the HCII test followed by Papanicolaou smear. RESULTS: For the screening group, the sensitivity was 0.69 and the specificity was 0.93; the area under the ROC curve was 0.81. The LR+ and LR- were 10.24 and 0.34, respectively. For the diagnosis group, the sensitivity was 0.88 and the specificity was 0.78; the area under the ROC curve was 0.83. The LR+ and LR- were 4.06 and 0.14, respectively. Sequential testing showed little or no improvement over the combination testing. CONCLUSIONS: The HCII test in the screening group had a greater LR+ for the detection of CIN 2/3 or worse. HCII testing may be an additional screening tool for cervical cancer in women 30 years and older.

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Infection with certain types of HPV is a necessary event in the development of cervical carcinoma; however, not all women who become infected will progress. While much is known about the molecular influence of HPV E6 and E7 proteins on the malignant transformation, little is known about the additional factors needed to drive the process. Currently, conventional cervical screening is insufficient at identifying women who are likely to progress from premalignant lesions to carcinoma. Aneuploidy and chromatin texture from image cytometry have been suggested as quantitative measures of nuclear damage in premalignant lesions and cancer, and traditional epidemiologic studies have identified potential factors to aid in the discrimination of those lesions likely to progress. ^ In the current study, real-time PCR was used to quantitate mRNA expression of the E7 gene in women exhibiting normal epithelium, LSIL, and HSIL. Quantitative cytometry was used to gather information about the DNA index and chromatin features of cells from the same women. Logistic regression modeling was used to establish predictor variables for histologic grade based on the traditional epidemiologic risk factors and molecular markers. ^ Prevalence of mRNA transcripts was lower among women with normal histology (27%) than for women with LSIL (40%) and HSIL (37%) with mean levels ranging from 2.0 to 4.2. The transcriptional activity of HPV 18 was higher than that of HPV 16 and increased with increasing level of dysplasia, reinforcing the more aggressive nature of HPV 18. DNA index and mRNA level increased with increasing histological grade. Chromatin score was not correlated with histology but was higher for HPV 18 samples and those with both HPV 18 and HPV 16. However, chromatin score and DNA index were not correlated with mRNA levels. The most predictive variables in the regression modeling were mRNA level, DNA index, parity, and age, and the ROC curves for LSIL and HSIL indicated excellent discrimination. ^ Real-time PCR of viral transcripts could provide a more efficient method to analyze the oncogenic potential within cells from cervical swabs. Epidemiological modeling of malignant progression in the cervix should include molecular markers, as well as the traditional epidemiological risk factors. ^

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This assessment compares the human papillomavirus (HPV) nationwide vaccine to the poliomyelitis vaccine and the swine flu vaccine with the purpose of finding parallels and lessons in the controversies faced by the development and use of the vaccines. There are a number of great barriers that are facing the HPV vaccine to date. These controversies lie in dealing with the risk involved in taking the vaccine, how much control the government should have in administering the vaccine, how to communicate the risk to the public, and the cost-effectiveness of the vaccine versus treatment for cervical cancer. The lessons for the HPV vaccine that were learned after comparison and assessment of the controversies were: (1) plan ahead of time on how to inform the public if a risk develops from taking the HPV vaccination and it may be better to provide some information while the event is occurring, always being as truthful as possible, and later dispensing more information once all of the facts are known, (2) the human papillomavirus is not something that will become a pandemic in a short amount of time because the virus takes a long time to develop into cervical cancer, so if a major risk begins to show after continuing to develop and administer the vaccine for an amount of time, it may be better to take it off the market for a while and possibly reconfigure it to help eliminate some of the risks, (3) if side reactions and risks do develop and the government assumes liability for these reactions, the cost-effectiveness can be greatly affected, so it is important to be constantly checking to see if all the monetary and health benefits of the vaccine are outweighing any of the negative costs of the vaccine, and lastly, (4) the public must feel that every aspect of the vaccine, both good and bad, has been thought over and the benefits of taking the vaccine prevail over the negatives and that politics and commercial interests have nothing to do with the production and administration of the vaccine. ^

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Background: With over 440 million cases of infections worldwide, genital HPV is the most frequent sexually transmitted infection. There are several types including high risk types 16, 18, 58 and 70 among others, which are known to cause cervical cell abnormality and if persistent, can lead to cervical cancer which globally, claims 288,000 lives annually. 33.4 million people worldwide are currently living with HIV/AIDS, with 22.4 million in sub-Saharan Africa where 70% of the female population living with HIV/AIDS is also found. Similar risk factors for HPV, cervical cancer and HIV/AIDS include early age at sexual debut, multiple sexual partners, infrequent condom use, history of STI and immune-suppression. ^ Objectives: To describe the role of HPV in cervical cancer development, to describe the influence of HIV/AIDS on HPV and in the development of cervical cancer and to describe the importance of preventive measures such as screening. ^ Methods: This is a literature review where data were analyzed qualitatively and a descriptive narrative style used to evaluate and present the information. The data came from searches using Pub Med, Cochrane Library, EBSCO Medline databases as well as websites such as the CDC and WHO. Articles selected were published in English over the last 10 years. Keywords used included: 'HPV, cervical cancer and HIV', 'HIV and HPV', 'HPV and cervical cancer', 'HPV infection', 'HPV vaccine', 'genital HPV', 'HIV and cervical cancer', 'prevalence of HIV and cervical cancer' and 'prevalence of cervical cancer'. ^ Results: Women with HIV/AIDS have multiple HPV types, persistent infection, are more likely to present with cervical neoplasia and are at higher risk for cervical cancer. Research also shows that HIV could affect the transmissibility of HPV and that HPV itself could also increase the susceptibility to HIV acquisition. ^ Conclusion: HIV, genital HPV and cervical cancer are all preventable. Need to emphasize programs that aim to increase HIV/AIDS, HPV and cervical cancer awareness. Stress importance of behavior modification such as frequent use of condoms, decreased sexual partners and delayed first intercourse. Facilitate programs for screening and treating HPV, male circumcision, effective management of HAART and HPV vaccination.^

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In the majority of cervical cancers, DNAs of high-risk mucosotpropic human papillomaviruses (HPVs), such as type 16, are maintained so as to express two viral proteins, E6 and E7, suggesting an essential importance to carcinogenesis. The high-risk HPV E6 proteins are known to inactivate p53 tumor suppressor protein but appear to have an additional, molecularly unknown function(s). In this study, we demonstrate that these E6 proteins can bind to the second PDZ domain of the human homologue of the Drosophila discs large tumor suppressor protein (hDLG) through their C-terminal XS/TXV/L (where X represents any amino acid, S/T serine or threonine, and V/L valine or leucine) motif. This finding is similar to the interaction between the adenomatous polyposis coli gene product and hDLG. E6 mutants losing the ability to bind to hDLG are no longer able to induce E6-dependent transformation of rodent cells. These results suggest an intriguing possibility that interaction between the E6 protein and hDLG or other PDZ domain-containing proteins could be an underlying mechanism in the development of HPV-associated cancers.

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Loss of genomic integrity is a defining feature of many human malignancies, including human papillomavirus (HPV)-associated preinvasive and invasive genital squamous lesions. Here we show that aberrant mitotic spindle pole formation caused by abnormal centrosome numbers represents an important mechanism in accounting for numeric chromosomal alterations in HPV-associated carcinogenesis. Similar to what we found in histopathological specimens, HPV-16 E6 and E7 oncoproteins cooperate to induce abnormal centrosome numbers, aberrant mitotic spindle pole formation, and genomic instability. The low-risk HPV-6 E6 and E7 proteins did not induce such abnormalities. Whereas the HPV-16 E6 oncoprotein has no immediate effects on centrosome numbers, HPV-16 E7 rapidly induces abnormal centrosome duplication. Thus our results suggest a model whereby HPV-16 E7 induces centrosome-related mitotic disturbances that are potentiated by HPV-16 E6.