21,017 research outputs found
HPV-18 transformed cells fail to arrest in G1 in response to quercetin treatment
Previous work with primary human keratinocytes demonstrated that quercetin, a potent mutagen found in high levels in bracken fern (Pteridium aquilinum), arrested cells in G1 with concomitant elevation of the cyclin-dependent kinase inhibitor (cdki) p27Kip1. Expression of the human papillomavirus type 16 (HPV-16) E6 and E7 oncoproteins, under transcriptional control of a heterologous promoter, in transformed keratinocytes failed to abrogate this arrest [Beniston, R., Campo, M.S., 2003. Quercetin elevates p27(Kip1) and arrests both primary and HPV-16 E6/E7 transformed human keratinocytes in G1. Oncogene 22, 5504–5514]. Given the link between papillomavirus infection, bracken fern in the diet and cancer of the oesophagus in humans, we wished to investigate further whether cells transformed by the whole genome of HPV-16 or HPV-18, with E6 and E7 under the transcriptional control of their respective homologous promoters, would be similarly arrested in G1 by quercetin. In agreement with earlier work, quercetin arrested HPV-16 transformed cells in G1 with an increase in the cyclin-dependent kinase inhibitor p27Kip1. However, HPV-18 transformed cells did not arrest after quercetin treatment. The failure of HPV-18 transformed cells to arrest in G1 was linked to the up-regulation of the HPV-18 long control region (LCR) by quercetin, maintaining high expression of the viral transforming proteins. Transcriptional up-regulation of the HPV-18 LCR was mediated by a “quercetin responsive element” homologous to the one identified previously in the bovine papillomavirus type 4 (BPV-4) LCR
Reactivity to human papillomavirus type 16 Ll virus-like particles in sera from patients with genital cancer and patients with carcinomas at five different extragenital sites
A retrospective seroepidemiologic study was performed to examine the association between human papillomaviruses (HPV) 16 infection and carcinomas of the oropharynx, the oesophagus, penis and vagina. Sera were selected from the serum bank from the Antoni van Leeuwenhoek Hospital (Netherlands Cancer Institute) and the Slotervaart Hospital in Amsterdam, the Netherlands. Presence of HPV 16 specific antibody was assessed using HPV 16 L1 capsids. Sera positive for HPV 16 capsid antibody were further tested for antibody against HPV 16 E7 peptides. Prevalence of antibody against H PV 16 L1 capsids among both the negative control group without cancer and the negative control group with gastric cancer was 18%, while seroprevalence among the control group of patients with HPV-associated cervical squamous cell carcinoma was 47% (P < 0.001). Among the patients with penile squamous cell carcinoma seroprevalence was 38% (P < 0.001), among patients with oropharyngeal carcinoma 33% (P = 0.04) and among patients with oesophageal squamous cell carcinoma 14% (P = 0.7). The serological evidence for association between HPV 16 infection and both oropharyngeal carcinoma and penile carcinoma was established. The conclusion that no association was found between the presence of antibody against HPV 16 L1 capsids and oesophageal squamous cell carcinoma was in accordance with results of other studies carried out in the Netherlands using HPV DNA technology. In the subjects with HPV 16 L1 capsid antibody, no association was found between the antibody against HPV 16 E7 and clinical outcome
Prevalence of human papillomavirus genotypes in women with normal and abnormal cervical cytology in Iran
Introduction: HPV infection has a prime etiologic role in development and progression of cervical cancer, one of the most frequent forms of cancer among women in developing countries. This study was designed to determine the most prevalent HPV genotypes in women with normal and abnormal cervical cytology in Iran. Materials and Methods: Samples from134 patients, including 127 who attended gynecology clinics and 7 with solid cervical tumors were used. All 127 patients underwent routine Pap tests for cytological evaluation and at the same visit a sample of cervical epithelial cells was obtained by scraping the cervix osteum. In each case HPV infection was primarily evaluated by PCR using GP 5/6 primers and then subtyping was performed in proved infected samples with specific primers for HPV 16, 18, 31, 33, 11 and 6. After cytological evaluation, 50 patients with abnormal Pap tests were categorized as the abnormal group and the remaining 77 patients as the normal group. Results: In the normal group, HPV infection was established in 10 cases (13% infection rate), while 30 HPV positive cases were discovered in the abnormal group (60% infected). The most prevalent genotypes among the infected samples were HPV 16 (76%), HPV18 (12.7%) and HPV11/6 (8.5%). Moreover, all 7 tumor samples were positive for HPV general primers of which, 5 samples were infected with HPV 16, two were co-infected with HPV16,18 and HPV16,31 genotypes and one was infected with HPV 18. Conclusions: Infection with HPV 16 was found to be significantly higher in abnormal group in comparison with normal group (42% vs. 11.6%, P value <0.005), likewise HPV18 genotypes were proved to be more prevalent in abnormal group (8% vs. 0%, P value <0.05). No significant relation between other HPV genotypes and pathologic cervical changes was obtained. According to our study high rates of infection with HPV genotypes in sexually active Iranian women makes molecular investigation for HPV16 and 18 very essential in clinical approaches to patients with proven dysplasia in their screening tests and also for those patients with borderline (i.e. ASCUS) or incongruous pathology reports. Larger studies are required to determine the most appropriate vaccine with highest protection in Iranian women
High Risk Human Papillomavirus in a Group of Portuguese Women
Human Papillomavirus (HPV) is the etiological agent for cervical cancer and genital warts. Worldwide, cervical cancer is the fourth most common cancer in women and the high risk HPV (HR-HPV), namely HPV 16 and 18 are responsible for the most of the cases. The objective was to analyze the HR-HPV frequency in a group of women referred for HR-HPV testing.
Clinical samples from 3117 women were perform by Cobas® HPV test (Roche Molecular Systems, CA, USA), this assay detected HPV 16 and HPV 18 and ‘Other HR-HPV’ (-31,-33,-35,-39,-45,-51,-52,-56,-58,-59,-66 and 68). Positive samples for ‘Other HR-HPV’ were sequenced for genotyping using MY09/11 primer´s.
HR-HPV frequency was 20.8% (649/3117). Among the positive samples, ‘Other HR-HPV’ was the most common (72.8%; 473/649). HPV 16 and 18 were detected only in 22.8% (148/649) and 7.4% (48/649) of the cases, respectively. 7.4% (48/649) of the positive women were infected with more than one HPV (34 with ‘Other HR-HPV’ + HPV 16; 8 with ‘Other HR-HPV’ + HPV 18; 5 with ‘Other HR-HPV’ + HPV 16 + HPV 18 and 1 with HPV 16 + HPV 18). Sequencing of ‘Other HR-HPV’ is ongoing and preliminary results shown the majority frequency for HPV 31 (11.7%) followed by HPV 56 (9.1%) and 8.9% for the HPV 66.
The HR-HPV frequency is high (20.8%), 30.4 % of these women were infected with HPV 16 or HPV 18 which is a high frequency. This study reveals the importance of the implementation of screening programs, and the use of HPV detection.N/
Modeling the consequences of regional heterogeneity in human papillomavirus (HPV) vaccination uptake on transmission in Switzerland
Background: Completed human papillomavirus (HPV) vaccination by age 16 years among women in Switzerland ranges from 17 to 75% across 26 cantons. The consequences of regional heterogeneity in vaccination coverage on transmission and prevalence of HPV-16 are unclear.
Methods: We developed a deterministic, population-based model that describes HPV-16 transmission among young adults within and between the 26 cantons of Switzerland. We parameterized the model using sexual behavior data from Switzerland and data from the Swiss National Vaccination Coverage Survey. First, we investigated the general consequences of heterogeneity in vaccination uptake between two sub-populations. We then compared the predicted prevalence of HPV-16 resulting from heterogeneous HPV vaccination uptake in all of Switzerland with homogeneous vaccination at an uptake that is identical to the national average (52%).
Results: In our baseline scenario, HPV-16 prevalence in women is 3.34% when vaccination is introduced and begins to diverge across cantons, ranging from 0.19 to 1.20% after 15 years of vaccination. After the same time period, overall prevalence of HPV-16 in Switzerland is only marginally higher (0.63%) with heterogeneous vaccination uptake than with homogeneous uptake (0.59%). Assuming inter-cantonal sexual mixing, cantons with low vaccination uptake benefit from a reduction in prevalence at the expense of cantons with high vaccination uptake.
Conclusions: Regional variations in uptake diminish the overall effect of vaccination on HPV-16 prevalence in Switzerland, but the effect size is small. Cantonal efforts towards HPV-prevalence reduction by increasing vaccination uptake are impaired by cantons with low vaccination uptake. Although the expected impact on national prevalence would be relatively small, harmonization of cantonal vaccination programs would reduce inter-cantonal differences in HPV-16 prevalence
Humán papillomavírus onkoproteinek hatása celluláris gének expressziójára = Effects of human papillomavirus oncoproteins on the expression of cellular genes
A genitális humán papillomavírusok (HPV) a méhnyakrák (cervix carcinoma) kialakulásának legfontosabb kockázati tényezői. A survivin fehérje az apoptózis gátlása mellett a sejtosztódás szabályozásában is részt vesz. Tranziens transzfekciós kísérleteinkben, a HPV 16 E6 szignifikánsan aktiválta a survivin gén promóterét. Úgy találtuk, hogy az E6 survivin promoterre gyakorolt hatását nagymértékben a p53 tumorszuppresszor fehérje közvetíti. Kimutattuk, hogy a HPV 16 E6 és E7 is képes az endogén survivin mRNS szintjét növelni humán embrionális fibroblaszt sejtekben. Különböző populációk összehasonlításával azt találtuk, hogy a survivin promóter (-31 G/C) polimorfizmusa nem befolyásolja jelentősen a méhnyakrák kialakulását. Az E-cadherin tumorszuppresszor gén promóter (-160 C/A) polimorfizmusának szerepét méhnyakrákos és laryngeális daganatok kialakulásában vizsgáltuk. Eredményeink szerint, az említett polimorfizmusnak sem a cervix carcinoma, sem a laryngealis carcinoma kialakulásában nincs lényeges szerepe. Primer humán keratinocytákban, a HPV 16 E6 csökkentette az involukrin és a transzglutamináz 1 expresszióját is. Tranziens transzfekciós kísérletekben, a HPV 16 E6 csökkentette az involukrin és a transzglutamináz 1 promóterek transzkripciós aktivitását. Eredményeink szerint tehát a HPV 16 E6 onkogén mindkét, a celluláris differenciálódás folyamatában alapvető fontosságú gén promóterét képes gátolni, ily módon befolyásolva a gazdasejt differenciálódási folyamatait. | Genital human papillomaviruses (HPV) are the main risk factors in the development of the cancer of the uterine cervix. Survivin protein has a major role both in the inhibition of apoptosis and in the regulation of the cell cycle. In our transient transfection experiments, HPV 16 E6 significantly activated the survivin gene promoter. We found that the effect of E6 on the survivin promoter is largely mediated by the p53 tumor suppressor protein. Both E6 and E7 were able to increase the level of endogenous survivin mRNA in human embryonic fibroblast cells. By analysing different patient populations, we found that the survivin promoter (-31 G/C) polymorphism has no significant role in the development of cervical cancer. We studied the E-cadherin tumor suppressor gene promoter (-160 C/A) polymorphism in cervical and laryngeal cancer samples. Our results suggest that this polymorphism has no major role in the development of cervical cancer or laryngeal cancer. In primary human keratinocytes, HPV 16 E6 decreased the expression of involucrin and transglutaminase 1. In transient transfection experiments, HPV 16 E6 decreased the transcriptional activity of involucrin and transglutaminase 1 promoters. Our results suggest that HPV 16 E6 is modulating the differentiation processes of its host cell by inhibiting the promoters of genes with essential roles in cellular differentiation
Antitumor effect of therapeutic HPV DNA vaccines with chitosan-based nanodelivery systems
Cervical cancer is the second-most-common cause of malignancies in women worldwide, and the oncogenic activity of the human papilloma virus types (HPV) E7 protein has a crucial role in anogenital tumors. In this study, we have designed a therapeutic vaccine based on chitosan nanodelivery systems to deliver HPV-16 E7 DNA vaccine, considered as a tumor specific antigen for immunotherapy of HPV-associated cervical cancer. We have developed a Nano-chitosan (NCS) as a carrier system for intramuscular administration using a recombinant DNA vaccine expressing HPV-16 E7 (NCS-DNA E7 vaccine). NCS were characterized in vitro for their gene transfection ability. Results: The transfection of CS-pEGFP NPs was efficient in CHO cells and the expression of green fluorescent proteins was well observed. In addition, NCS-DNA E7 vaccine induced the strongest E7-specific CD8+ T cell and interferon γ responses in C57BL/6 mice. Mice vaccinated with NCS-DNA E7 vaccine were able to generate potent protective and therapeutic antitumor effects against challenge with E7-expressing tumor cell line, TC-1. Conclusions: The strong therapeutic effect induced by the Chitosan-based nanodelivery suggest that nanoparticles may be an efficient carrier to improve the immunogenicity of DNA vaccination upon intramuscular administration and the platform could be further exploited as a potential cancer vaccine candidate in humans. © 2014 Tahamtan et al
Distribution of human papillomaviruses and bacterial vaginosis in HIV positive women with abnormal cytology in Mombasa, Kenya
Background: HPV is the major etiological factor in the causal pathway for cervical cancer, which is the leading cancer among women in sub-Saharan Africa. HIV is associated with a higher prevalence and a broader range of high-risk HPV genotypes. Studies have shown a positive association between Bacterial vaginosis (BV) and HPV and HIV. Also, in African women, BV was found to be significantly associated with vaginal inflammation. The high prevalence of BV, HIV and HPV infections in the African continent makes elucidation of the interactions with one another of utmost public health interest. The aims of the current study are to examine the frequency of HPV genotypes and BV as well as their respective risk factors within an HIV infected population with abnormal cytology in the resource-constrained setting of Mombasa, Kenya and, secondly, highlight issues to consider for triple co-infection clinical management.
Method: Cross-sectional analysis with a sample drawn from an ongoing cohort study. All consenting, non-pregnant HIV infected women, between 18 and 50 years of age, without a history of cervical cancer or hysterectomy, between November 2005 and April 2006 were screened for HR HPV DNA in Mombasa, Kenya. 1 out of 4 HIV positive women fulfilled the criteria by having SIL (24.9 %). 600 HIV infected women were tested to reach a cohort of 74 HIV women with abnormal cytology. To assess which factors were associated with HR HPV, crude statistical analysis was performed through logistic regression.
Results: Bacterial vaginosis (BV) was found in 46 women out of 74 (62.2 %). Cervicitis was diagnosed in 15 % of women (n = 11), of which 8 had BV. The most prevalent HPV genotypes were HPV 16 (33.8), HPV 53 (24.3) and HPV 18 (17.6 %), while 65 % of the participants had multiple genotype infection. Statistically significant associations between CD4 counts = 350 mu l and HPV 16 adjusted for age (OR = 2.9; 95 % CI: 1.0-8.3; p = 0.05). A borderline statistically significant association was observed between BV and HPV58 (crude OR = 4.1, 95 % CI: 0.8-21.0; p = 0.07).
Conclusion: The most prevalent HPV genotypes observed were HPV 16, HPV 53, and HPV 18, which have a combined prevalence of 76 %. Our results show that a triage based on CD4 count should start at CD4 count >= 350 mu l as our study suggests that HPV 16 are more prevalent when women are moderately immunosuppressed. Given the high prevalence of HPV 53 in a HIV infected population with abnormal cytology, its cervical carcinoma genesis potential as a stand-alone genotype and as well as its synergism with multiple infections should be investigated. The new WHO guideline in resource-poor settings to rescreen women for HPV within ten years may be more effective if BV and cervicitis management become a major component for HIV-HPV management
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