Martina Salakova

Demographic and risk factors in patients with head and neck tumors

The association between human papillomavirus (HPV) infection and the development of head and neck cancer has been documented recently. In this study on 86 head and neck cancer patients and 124 controls, data regarding demographics, behavioral risk factors, and risks related to HPV exposure were collected. HPV detection was carried out using polymerase chain reaction in the tumors and in oral exfoliated cells, and HPV typing by a reverse line blot assay specific for 37 HPV types. Sera were tested by an enzyme‐linked immunosorbent assay specific for HPV proteins. Head and neck cancer cases report significantly more oral‐anal contact (Pu2009=u20090.02) and tobacco and alcohol use than controls (Pu2009=u20090.001; Pu2009=u20090.02, respectively). High‐risk HPV DNA was detected in 43% of oral washings of cases and 4% of controls (Pu2009<u20090.0001). The association between the presence of high‐risk HPV DNA in oral exfoliated cells and in tumor tissues was statistically significant (adjusted Pu2009<u20090.0001). The prevalence of HPV‐specific antibodies was significantly higher in cases than in controls (adjusted Pu2009<u20090.0001). These results provide epidemiological and immunological evidence for HR HPV as a strong risk factor (ORu2009=u200944.3, Pu2009<u20090.0001) for head and neck cancer, even after controlling for age, tobacco and alcohol use. The detection of high‐risk HPV DNA in oral exfoliated cells and HPV‐specific antibodies in serum can be considered as clinically relevant surrogate markers for the presence of a HPV‐associated head and neck cancer, with a high sensitivity (83%) and specificity (88%). J. Med. Virol. 81:878–887, 2009.

HPV involvement in tonsillar cancer: Prognostic significance and clinically relevant markers

The association of high‐risk human papillomaviruses (HR HPVs) with tonsillar cancer (TC) has been documented. Because patients with HPV‐associated tumors show better survival rates, modification of their treatment regimen is being considered. It is therefore crucial to find markers for the identification of patients whose tumors are linked to viral infection. A cohort of 109 patients with primary TC was screened for HPV DNA presence in the tumor tissues and HPV‐specific antibodies in sera. Data regarding risk factors and clinical parameters were collected. Forty‐five specimens were analyzed for the expression of viral E6 and E2‐region mRNA, and the p16 and p53 protein expression status was assessed by immunohistochemistry. The overall prevalence of HPV DNA in TC tissues was 65.1%. Ninety‐three percent of HR HPV DNA‐positive samples expressed E6*I mRNA. E2‐region mRNA expression was detected in 36% of positive samples, which implies that the virus is integrated in 64% of HPV DNA/RNA‐positive tumors. p16 overexpression and the presence of antibodies specific to HPV16 E6/E7 oncoproteins correlated well with HPV DNA and RNA presence. The disease‐specific survival rate of patients with HPV DNA‐positive tumors was significantly higher than that of HPV DNA‐negative patients. In addition to providing further evidence of the involvement of HPV infection in the etiopathogenesis of a proportion of TC cases, our study demonstrates that p16 immunostaining and anti‐E6/E7 antibodies as surrogate markers of HPV involvement represent specific, sensitive and clinically accessible assays for the identification of TC patients who have a considerably better prognosis.

Human papillomavirus (HPV) profiles of vulvar lesions: possible implications for the classification of vulvar squamous cell carcinoma precursors and for the efficacy of prophylactic HPV vaccination.

The term vulvar intraepithelial neoplasia (VIN) introduced in 1986 incorporates 3 grades of usual VIN (u-VIN I-III) and the differentiated VIN (d-VIN). Although u-VIN is etiologically associated with the human papillomavirus (HPV) infection, d-VIN represents an alternative HPV negative pathway of vulvar carcinogenesis. In 2004, the u-VIN I category was abandoned and u-VIN II and III were merged. Further, an alternative Bethesda-like terminology scheme presenting the term vulvar intraepithelial lesion was proposed recently. To analyze the impact of HPV profiles of vulvar precancerous lesions for their classification and to assess the presumable efficacy of the prophylactic HPV vaccination, 269 vulvar excisions representing lichen sclerosus, lichen simplex chronicus, condylomata acuminata, d-VIN, all grades of u-VIN and squamous cell carcinomas were subjected to the HPV typing by use of GP5+/6+ polymerase chain reaction and reverse line blot hybridization. The results showed different HPV profiles, and also differing frequency of multiple-type HPV infection and the age structure in patients with u-VIN II and III. The biologic heterogeneity within the u-VIN II category was also demonstrated. u-VIN I was distinguished as a rare disorder associated with high-risk HPV infection. We conclude that the original VIN terminology proposed in 1986 seems to be appropriate for the classification of vulvar squamous dysplastic lesions. The spectrum of HPV types found in vulvar squamous cell carcinomas indicates that the efficacy of HPV vaccination in preventing vulvar cancer might be diminished in the studied population, because the recently developed prophylactic vaccines are targeted against a limited number of HPV types.

Evaluation of Different Techniques for Identification of Human Papillomavirus Types of Low Prevalence

ABSTRACT Human papillomaviruses (HPVs) have been recognized as etiologic factors in a variety of diseases. Due to the large number of HPV types, methods for HPV genotyping are difficult to standardize. Despite this fact, several methods exist, and some of them are available commercially. In this study, we evaluated the Roche Diagnostics linear array (LA) HPV genotyping assay, the Innogenetics INNO-LiPA (line probe assay [LiPA]), and two noncommercial reverse line blot (RLB) assays based on either primers GP5+ and GP6+ (GP) or newly designed broad-spectrum primers BSGP5+ and BSGP6+ (BS). The reliabilities of these assays were tested with a wide spectrum of HPV types less prevalent in cervical samples. This is the first study to compare the performance of the most widely used HPV genotyping methods with selected samples positive for low-prevalence HPV types. We focused on interassay agreement, both overall and type specific, in cases with single and/or multiple HPV infections. Interassay agreement was moderate in cases of single HPV infections and poor in cases of multiple HPV infections. The LA and the BS-based RLB assays found a higher rate of cases positive for multiple HPV types than LiPA and the GP-based RLB assay. The weakest capability in detecting multiple HPV infections was observed for LiPA. The use of only one assay in epidemiological and clinical studies might lead to biased conclusions. Therefore, a universally evaluated and agreed upon HPV typing assay or a combination of current assays is needed for possible clinical applications, and knowledge of their limitations is advised.

Nodal status is not a prognostic factor in patients with HPV‐positive oral/oropharyngeal tumors

The primary aim is to compare the prognostic parameters in patients with HPV‐positive and HPV‐negative tumors. The secondary aim is to compare the patterns of treatment failure between these groups.

Human papillomavirus infection and tumours of the anal canal: correlation of histology, PCR detection in paraffin sections and serology†

Human papillomavirus infection is an important etiological factor in squamous cell carcinoma of the anus (SCCA). Different histological variants of anal carcinomas displaying squamous differentiation, previously classified as separate tumours, were recently reclassified as SCCA by the WHO. In our recent study the presence of HPV was detected by PCR in biopsy specimens of 42 different anal tumours, including SCCA and its histological variants (n=22), adenocarcinomas (n=5), tubulovillous adenomas (n=5) and anal condylomas (n=10). HR HPV16 (high risk – HR) was detected in 18 of SCCA specimens (81.8%). All histological variants, i.e. tumours with basaloid, squamous and mixed histological patterns, were represented among the HPV‐positive cancers. Four tumours (18.2%) were HPV negative. Low‐risk (LR) HPV types were not detected within the SCCA group. HPV16 was identified in one adenocarcinoma, while four cases were HPV negative. Two adenomas showed presence of HPV16; one showed simultaneous positivity for HPV33. The remaining three tumours were HPV negative. Seven anal condylomas (70%) were LR HPV 6 and/or 11 positive, while three were HPV negative. The presence of HR HPV types was not observed in anal condylomas. Our results provide further evidence in support of the etiological role of HR HPV infection in the development of SCCA regardless of its histological appearance.

Markers of HPV infection and survival in patients with head and neck tumors

The purpose of this study was to determine whether changes in human papillomavirus (HPV) DNA prevalence in oral rinses and/or HPV‐specific antibody levels in the sera of patients with oral/oropharyngeal cancer have prognostic significance. One hundred and forty‐two patients with oral/oropharyngeal tumors were enrolled. The presence of HPV DNA was assayed in tumor tissue and oral rinses and HPV‐specific antibodies were assessed in the sera. Oral rinses were collected before treatment and one year after the treatment. Sera were drawn before treatment, one month, and one year after the end of the treatment. Altogether, 59.2% of tumors were HPV positive. The presence of HPV DNA in the tumors correlated with HPV DNA positivity in oral rinses and with HPV‐specific antibodies in the sera. Out of 66 patients with HPV‐positive oral rinses at enrolment, 84.8% became negative at one‐year follow‐up, while most patients remained seropositive for HPV‐specific antigens. However, the mean titers of HPV16 E6 and/or E7 antibodies at follow‐up were significantly lower. Of 16 patients with recurrences at follow‐up (alive on second sampling), six were positive at enrolment for HPV16 E6 and/or E7 antibodies. In five of these, no decrease in antibody levels was observed. Titers of antibodies specific for HPV16 capsid antigens did not change during the follow‐up. Our data suggest that the detection of antibodies specific for the HPV 16 E6 and E7 oncoproteins may serve not only as a marker of HPV etiology, but also as a marker of recurrence and a prognostic indicator in patients with HPV‐positive tumors.

Correlation between human papillomavirus-associated cervical cancer and p53 codon 72 arginine/proline polymorphism

Abstract. High-risk mucosal human papillomaviruses encode an E6 oncoprotein, which binds the cellular p53 tumor suppressor protein, thereby marking it for degradation through the ubiquitin-mediated pathway. A common p53 polymorphism at codon-72 of exon 4 results in translation to either arginine or proline. Recently reported data suggested an increased susceptibility to E6/ubiquitin-mediated degradation of the Arg72-p53 isoform and an over-representation of the homozygous Arg72-p53 genotype in cervical cancer patients. We have analyzed this polymorphism in a larger series of patients with cervical cancer and in controls in the Czech Republic. We found no statistically significant differences between the codon-72 p53 genotypes of cervical cancer patients and the control women. Based on these results, it is unlikely that Arg72-p53 is associated with an increased risk for human papillomavirus-associated cervical tumor development in Czech women.

Age-specific prevalence, transmission and phylogeny of TT virus in the Czech Republic

BackgroundTT virus is prevalent worldwide, but its prevalence and genotype distribution in Central and East-Europe has not been determined. The high prevalence of TTV in multiply-transfused patients points to the importance of a parenteral mode of transmission, but since more than half of the general population is infected other possible routes of transmission must be considered.MethodsIn our study, we investigated the epidemiology, transmission and phylogeny of TTV in the Czech Republic. The following groups were selected: a control group of 196 blood donors, 20 patients with hemophilia, 49 intravenous drug users, 100 sex workers, 50 penitentiary prisoners, 208 healthy children aged 1 to 14 years, 54 cord blood samples, 52 patients with non-A-E hepatitis, 74 patients with hepatitis C, and 51 blood donors with increased ALT levels. Primers specific for the non-coding region were used. The genotype distribution was studied in 70 TTV-positive samples.ResultsThe prevalence rate of TTV among the Czech population was 52.6%. We have shown that TTV is not transmitted prenatally. Children were infected after birth with two peaks: one at the age of two years and the other after the beginning of primary school. Adults have shown a further increase in the TTV prevalence with age. The highest TTV prevalence was found in the group of patients who had received multiple blood transfusions. The TTV prevalence rate in subjects at an increased risk of sexual transmission was not significantly higher than in the general population. Genotypes G2 and G1 were most prevalent among the Czech population, followed by G8 and G3. The subjects positive for markers of HBV and/or HCV infection tested significantly more often TTV DNA positive, which is suggestive of a common route of transmission of these three infections.ConclusionsThis study on TTV prevalence, mode of transmission and age-specific prevalence is the most extensive study performed in Central and Eastern Europe. It showed insights into the epidemiology of TTV infection, but failed to associate TTV infection with clinical manifestations.

Analysis of the integration of human papillomaviruses in head and neck tumours in relation to patients' prognosis.

Integration, which leads to the disruption of the circular HPV genome, is considered as a critical, albeit not obligatory, step in carcinogenic progression. Although cervical carcinomas with extrachromosomal HPV plasmid genomes have been described, the virus is integrated in 70% of HPV16‐positive cervical tumours. Limited information is available about HPV integration in head and neck tumours (HNC). In this study, we have characterised the physical status of HPV in a set of tonsillar tumour samples using different methods—the mapping of E2 integration breakpoint at the mRNA level, the 3’ RACE based Amplification of Papillomavirus Oncogene Transcripts (APOT) assay and Southern blot. Furthermore, the impact of HPV integration on patients prognosis has been evaluated in a larger set of 186 patients with head and neck cancer. Based on the analysis of E2 mRNA, HPV was integrated in the host genome in 43% of the HPV‐positive samples. Extrachromosomal or mixed form was present in 57%. In fresh frozen samples, the APOT and E2 mapping results were in agreement. The results were confirmed using Southern blotting. Furthermore, the type and exact site of integration were determined. The survival analysis of 186 patients revealed HPV positivity, tumour size and lymph node positivity as factors that influence disease specific survival. However, no statistically significant difference was found in disease specific survival between patients with HPV‐positive integrated vs. extrachromosomal/mixed forms of the virus.