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The aim of this study was to analyse the prevalence of human papillomavirus (HPV) infection among patients with oral and oropharynx squamous cell carcinoma (OSCC). The correlation between HPV infection and OSCC, HPV genotypes, and correlation between HPV, OSCC, alcohol use, tobacco smoking, demographic data (gender, age, place of residence), anatomic location, pretreatment staging, metastases of lymph node evidence, and grading was investigated. In the examination group, there were 60 patients with squamous cell carcinoma (SCC), 54 males and six females. Twenty-one patients were affected with oral, 24 - with oropharynx, and 15 - with oral and oropharynx SCC. The patients were not subjected to chemotherapy and radiotherapy before operation. The examination samples were collected from paraffin sections. This analysis involved DNA isolation from histological specimens, an amplification of a fragment of human ß-globin gene (reference gene), electrophoresis of amplification products of the gene, a quantitative DNA analysis (using spectrophotometry method), PCR, and genotyping. HPV DNA was detected in 25% of patients with SCC. Among HPV positive patients, 86.7% of the patients were infected with HPV type 16 and 13.3% were infected with another non identified HPV.
Human Papillomavirus (HPV) is one of the DNA viruses which are closely related to cervical carcinogenesis. c-FOS plays a key role in initiation and maintenance of expression of HPV E6 and E7 oncoproteins in cervical carcinogenesis combined with infection with oncogenic types of HPV. AP-1 is considered to be a positive regulator which recognizes sequences in 5'HPV DNA regulatory region (LCR). Mutations in FOS gene, nuclear transcription factor coding proteins binding to specific DNA sequences occur with a frequency of 20-25% in various neoplasms in humans. The purpose of the study was identification of point mutation in c-FOS gene from cervical squamous carcinoma cells, high grade cervical intraepithelial neoplasia cells and normal cervical epithelium.The study group consisted of 35 postoperative tissues from patients diagnosed with high grade dysplasia and 29 postoperative tissues from patients diagnosed with squamous cell cervical carcinoma. The control group consisted of normal cervical tissue specimens obtained from 33 patients that underwent hysterectomy due to uterine leiomyomas. Identification of point mutation in c-FOS gene exon 4 was performed using PCR - SSCP technique. Mutation in 450 nucleotide fragment of c-FOS gene was found in none of the studied samples.
Human papillomavirus (HPV) infection is a major risk factor for the development of cervical cancer. The HPV-induced immortalization of epithelial cell usually requires integration of the viral DNA into the host cell genome. The integration event causes disruption of the E2 gene and this is followed by overexpression of the E6 and E7 oncoproteins. 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. We used an in vitro cell culture model to explore the role of the E2 protein in the transcriptional control of the HPV16 long control region. Employing transient and stable transfection experiments we simulated the episomal and integrated states of the viral genome, respectively. We show that the E2 protein up-regulates E6/E7 transcription from episomal DNA but represses it in the case of integrated DNA. The activator function of the E2 protein seems to counteract the repressive chromatin structure formed over episomal DNA. Steroid hormones and retinol also modulate oncogene transcription differently depending on the physical structure of the viral DNA. Our data suggest regulatory mechanisms involving interactions between the E2 protein and nuclear hormone receptors.
In 48 adult women, subdivided into group 1 with no cervical intraepithelial neoplasia (CIN-negative) and group 2 (CIN-positive), endocervical scrapes were tested for the presence EBV DNA and HPV DNA using PCR-ELISA. In addition, attempts were made to detect HPV 16 and HPV 18 using other PCR amplification techniques. In parallel, in biopsies of uterine cervix obtained from group 2 patients, presence of EBER was documented by RNA in situ hybridization (ISH). Sera of all patients were tested for anti-EBV antibodies. In group 1, presence of EBV DNA was noted in the material obtained from 8 women (30.8%), while HPV DNA was detected in 2 women (7.7%). In group 2, EBV DNA was present in the material obtained from 11 patients (50%), including 7 (31.8%) with HPV DNA also identified. In 5 women (22.7%) of group 2 only HPV DNA was detected. The identifical HPV DNA in all cases belonged to HPV 16 type. Both in group 1 and in group 2, all patients were found to carry serum IgG-anti-VCA and IgG-anti-EBNA antibodies. The results allow to conclude that, co-infection with EBV and HPV 16 may be of cervical significance in etiopathogenesis of uterine cervical cancer.
Objectives: Molecular mechanism of carcinogenesis associated with high risk (HR) type HPV is related to the activity of virus oncoproteins E5, E6 and E7. Their task is to bring the cells to a state enabling synthesis of viral DNA, copying viral particles and promotion of uncontrolled cell growth. Proliferative factors of a feminine genital tract epithelium are also sex hormones — estradiol and progesterone. Steroids influence the transcription of genes involved in cell cycle, acting through specific nuclear receptors (ER and PR). The aim of this study was evaluation of the effect of selected concentrations of 17ß-estradiol and progesterone on survival and proliferation of HeLa line cells. Material and methods: The study was done on a transformed HeLa cell line containing integrated genome HPV of type 18. The lines were incubated in the presence of 17ß-estradiol at the concentrations of lx10-4M, lx10-5M, lx10-7M, lx10-8M. Cell survival was determined with the use of 0.5% of water solution of toluidine blue and the cell proliferation rate were evaluated with the use of BrdU Labelling and Detection Kit and the method ELISA (Roche). Results: The obtained results point to 10% toxic influence on HeLa line cells of 17ß-estradiol at high concentrations after 72 h of incubation. The influence of the hormone on proliferation rate was diversified depending on the hormone concentration and time.
 Cervical carcinogenesis is a complex problem with papillomavirus widely accepted as a causative agent. Integration of a human papillomavirus (HPV) of the high-risk type into the host cell genome is one of the major contributing factors to cervical malignant transformation. In this study, the correlation of CMV, EBV, HSV-1, HSV-2, HHV-6 and HHV-7 infections with the physical status of the HPV genome in cervical cancer and precancerous cervical lesions was investigated in sixty HPV-16-positive women. Cervical secretion samples were submitted to DNA extraction and analyzed by PCR. HPV-16 DNA was confirmed in genotyping with the reverse hybridization line probe assay. Multiplex PCR with specific primers for the E2/E6 genes was used to assess the viral integration status of HPV-16. Our results show that CMV DNA was more frequently present in samples with mixed forms of HPV-16 than in the episomal form (P < 0.025). Such a correlation was also observed in the case of EBV (P < 0.005). The presence of CMV resulted in a six-fold (OR 6.069; 95% CI 1.91-19.22; P = 0.002), while EBV caused a seven-fold (OR 7.11; 95% CI 1.70-29.67; P = 0.007) increase in the risk of the integrated or mixed HPV-16 genome occurrence. Our data suggest that coinfection with herpesviruses, especially CMV and EBV, may be involved in the integration of the HPV-16 genome and may contribute to the development of cervical cancer.
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