The long control region (LCR) and the E2 protein of human papillomaviruses (HPV) are the most important viral factors regulating transcription of the viral oncogenes E6 and E7. Sequence variation within these genomic regions may have an impact on the oncogenic potential of the virus. Sequence variation in the LCR and in the E2 gene of human papillomavirus type 16 (HPV-16) isolates originating from cervical cancer patients from East Hungary was studied. In 30 samples, sequencing and/or single-strand conformation polymorphism analysis revealed variants belonging to the European variant lineage of HPV-16. These variants differed from the reference European clone only slightly in their E2 and LCR sequences. Three samples represented variants belonging to the Asian-American group. These differed from the published reference sequence at several positions in the LCR and E2 regions. Compared to the reference clone, the LCR clones of the European isolates showed very similar transcriptional activities, while that of an Asian-American isolate had " 1n7-fold increased activity. Most of the increased activity of the Asian-American isolate could be ascribed to nucleotide changes found at the 3h end of the LCR (nt 7660-7890). The transcriptional transactivation potentials of the HPV-16 E2 isolates differed only slightly from each other, and the differences seemed to be independent of the taxonomic position of the isolates.
We tested 65, 44, and 116 patients with oral squamous cell cancer (OSCC), oral leukoplakia (OL), and oral lichen planus (OLP) against 68 age‐matched controls for the presence of Epstein–Barr virus (EBV). Apparently healthy mucosa was simultaneously sampled and examined in all patients. Paraffin‐embedded tissue sections of all EBV‐positive patients with OSCC were examined for latent membrane protein‐1 (LMP‐1) expression (demonstrable in most EBV‐associated malignancies) using immunohistochemistry. The prevalence of EBV in the controls and in OSCC, OL, and OLP lesions was 19.1%, 73.8%, 29.5%, and 46.6%, respectively, and 66.2%, 22.7%, and 31.9% in the healthy mucosa of patients, respectively. The prevalence of EBV in OSCC patients was significantly higher than in controls or in respective samples of the other two patient groups both in the lesion and in the healthy mucosa. Comparisons including only patients with EBV‐negative lesions yielded similar results. Lesions of patients with OLP, but not of patients with OL, differed significantly from controls in EBV prevalence. In OSCC, LMP‐1 expression was not detected, and EBV carriage was not significantly associated with any risk factors and did not influence the outcome. Although a high prevalence of EBV was found in OSCC, comparable carriage rates on healthy mucosa of patients indicated that an aetiological role of EBV is unlikely.
Background: Survivin, a novel member of the inhibitor of apoptosis family, plays an important role in cell cycle regulation. A common polymorphism at the survivin gene promoter (G/C at position 31) was shown to be correlated with survivin gene expression in cancer cell lines. Aim: To investigate whether this polymorphism could be involved in the development of human papillomavirus (HPV)-associated cervical carcinoma. Methods: Survivin promoter polymorphism was detected in patients with cervical cancer, in patients with equivocal cytological atypia and in a control population using polymerase chain reaction (PCR-restriction fragment length polymorphism (RFLP) and PCR-single strand conformation polymorphism analysis. HPV was typed in patients with cervical cancer and cytological atypia using PCR-RFLP. Results: No statistically significant differences were found in the genotype distributions of the survivin promoter variants among our study groups. Conclusions: The survivin promoter polymorphism at position 31 may not represent an increased risk for the development of cervical cancer, at least in the population studied here.
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