Association Of Human Papillomavirus Type Research Articles

Association of Human Papillomavirus Type 16 Long Control Region Variations with Cervical Cancer in a Han Chinese Population.

Objective: High-risk human papillomavirus (HPV) E6 and E7 proteins are the major oncoproteins involved in the tumorigenesis of cervical cancer. The long control region (LCR) in HPV plays an important role in regulating the expression of the E6 and E7 oncogenes. In the current study, we investigated the association of HPV16 LCR variations with cervical cancer.Methods: A total of 139 HPV16-positive cervical cancer patients (case group) and 116 HPV16-positive asymptomatic individuals (control group) were enrolled in the current study. Then, the HPV16 LCR was sequenced to determine the association between LCR variations and cervical cancer.Results: In the current study, HPV16 A1-A3 (19.4%), A4 (78.4%) and D3 (2.2%) variants were found in the case group. However, only A1-A3 (34.5%) and A4 variants (65.5%) were found in the control group. The distribution of the HPV16 variants between the case and control groups was significantly different (P=0.009). Moreover, a total of eleven variations (A7167G, A7173C, C7176T, C7200T, T7269C, C7286A, C7729A, C7763T, A7841G, G7867A and T24C) were significantly different between the case and control groups (P<0.05). For the sub-lineage analysis, only C7873G variations were significantly different between the case and control groups in the A4 (As) variant (P=0.039).Conclusion: Our results showed that specific variations in the HPV16 LCR were associated with cervical cancer. Our study will provide a good reference for further understanding of the relationship between HPV16 LCR variation and cervical cancer.

Genetic variability and oncogenic risk association of human papillomavirus type 58 E6 and E7 genes in Taizhou area, China

It is well recognized that the association of human papillomavirus (HPV) and cervical carcinogenesis is based on the presence of HPV DNA sequence. The E6 and E7 oncoproteins encoded by high-risk HPV types play a key role in carcinogenesis. HPV58 type accounts for a larger share of cervical disease in China, whereas data on HPV58 genetic variability in China is limited. We aimed to evaluate the diversity of HPV58 genetic variants by sequencing the entire E6 and E7 genes. Phylogenetic trees were constructed by Maximum likelihood method by MEGA 5.05 software. In this study, the overall HPV infection rate was 22.6% (2891/12780) in Southeast China and the prevalence of HPV58 infection rate was 2.6% (335/12780). 26 nucleotides substitutions were observed in E6 and E7 genes with 10 novel substitutions and 17 non-synonymous substitutions. We obtained 25 distinct variation patterns which the accession GenBank numbers as MH348918-MH348942. All of HPV58 variants belong to lineage A, while no lineage B, C and D were detected in Taizhou area, Southeast China. The sublineage A1, A2, and A3 variants were found in 136 (68.3%), 39 (19.6%), and 24 (12.1%) of HPV58 isolates, respectively. The sublineage A3 variants with T20I/G63S substitutions at E7 oncoprotein carried a significantly higher risk for high-grade cervical intraepithelial neoplasia (CIN2 or worse, CIN2+) when compared with other HPV58 variants (odds ratio = 4.41, P < 0.05). Nevertheless, there was no association between HPV58 (sub) lineages and cervical lesions. These data provide the critical characteristics of HPV58 variants to assist further investigation of carcinogenic association and the development of next generation vaccines and diagnostic assays in China.

The association of human papillomavirus type 16 E2 variations with cervical cancer in a Han Chinese population

Human papillomavirus type 16 (HPV16) is considered to be the primary pathogen related to cervical cancer. The HPV16 E2 protein plays an important role in tumourigenicity of cervical carcinoma. In the current study, we enrolled 121 HPV16-positive cervical cancer patients in the case group and 130 HPV16-positive asymptomatic individuals in the control group, and we investigated the association between HPV16 E2 gene variations and cervical cancer. The HPV16 E2 DNA was amplified and sequenced. We identified two HPV variants (EUR and As) in the control group; the As variant was predominant (68.5%), followed by the EUR variant (31.5%). In the case group, three HPV variants (EUR, As and AA) were observed; the As variant was predominant (72.7%), followed by the EUR variant (22.3%) and the AA variant (5.0%). Our results showed a significant difference in the distribution of the HPV16 variants between the case and control groups (P < 0.05). Moreover, in the HPV16 E2 gene variation analysis, the distribution of sixteen variations was significantly different between the case and control groups (P < 0.05), and all of these variations were present in the AA variant. In the subgroup analysis, the frequency of the T3575G (S274A) variation in the EUR variant was significantly different between the case and control groups (P = 0.029); however, there was no significant difference in the frequency of the variations in the As variant between the case and control groups. Our findings in the current study could provide a better understanding of the relationship between HPV16 variants, E2 gene variations and cervical cancer.

Association of human papillomavirus type 16 and its genetic variants with cervical lesion in Korea.

Persistent human papillomavirus type 16 (HPV16) is the major risk factor for cervical cancer. HPV16 intratypic variants differ in their geographical distribution and oncogenic potential. This study aimed to analyze the distribution of HPV16 variants and their association with cervical lesion histopathology in Korean women. In total, 133 HPV16-positive cervical samples from women admitted to Seoul National University Boramae Hospital were analyzed by sequencing E6, E7, and L1 genes and the long control region (LCR), and the variant distribution according to cervical lesion grade was determined. Isolates were grouped into a phylogenetic lineage, and A1-3, A4, C, and D sublineages were detected in 54.1, 37.8, 0.7, and 7.4% of samples, respectively. The most commonly observed LCR variations were 7521G>A (91.5%), 7730A>C (59.6%), and 7842G>A (59.6%). Furthermore, A4 or D sublineage-positive women had a higher risk for cervical cancer than women who were positive for A1-3. Among HPV phylogenetic clusters, A1-3 was the predominant sublineage, and within A1-3, the 350G polymorphism was highly frequent. These results differed from those of previous studies in Korea and other Asian countries. The findings suggest that cervical neoplasia incidence in HPV16-infected patients could be affected by the distribution of HPV16 variants in the population.

P10.07 Mapping the integration sites e1-e2 of hpv-16 andhpv-18 as a tool to evaluate different stages of cervical disease progression

Introduction Different methodologies have been developed to analyse integration. Most of them are expensive and laborious. Since the most frequent disrupting happen in E1 or E2 genes we believe that amplify fragments covering theses genes could be associated to virus integration status. Methods Hence, in order to evaluate the physical state (episomal or integrated) of HPV 16 and 18 genomes, a PCR combining 10 primers pairs for HPV16 and 11 primers pairs for HPV18 were used, covering the E1-E2 region, adapted as described by Vernon et al. (1997)1 and Collins Constandinou-Williams et al. (2009).2 CASKI and HeLa lineage were used as control. Results Our preliminary results involved 93 samples cervical samples from patients infected by HPV16 and 37 by HPV18, harbouring cervical lesions in different stages of progression, except HPV18, exclusively associated with cancer lesions. Among HPV16, 26 (28%) were presented episomal, 30 (32%) mixed and 37 (40%) integrated forms. The upper region E1a were the most frequently absent (disrupted) (n = 30, 32%), followed by the downstream E2c region, (n = 21, 22,6%). Among HPV 18 cervical cancers, 5 (13,5%) were presented as episomal forms, 8 (21,5%) mixed and 24 (65%) were integrated. The downstream region E2P3 was the most frequently disrupted, (n = 30, 81%). Conclusion It is interesting to observe that literature points out a predominance of disruption in E2 region but our results suggested a highly prevalent E1 inactivation. The approach here described is a very specific methodology that can successfully map the HPV 16 and 18 genome fragile areas. Data are being analysed in order to search for statistical correlation between integration and severity of the lesion but it has been observed that E1-E2 absences were suggestively frequent in HSIL and cancer. In a few cases, episomal forms were observed in cancer samples, suggesting additional biomarkers as responsible for carcinogenesis. Disclosure of interest statement PCR, Genomic integration, episomal, HPV16. Financial support: Bolsa Capes, Faperj APQ1. References Vernon SD, Unger ER, Miller DL, et al. Association of human papillomavirus type 16 integration in the E2 gene with poor disease-free survival from cervical cancer. Int J Cancer 1997;74:50–6 Collins SI, Constandinou-Williams C, Wek K, et al. Disruption of the E2 gene is a common and early event in the natural history of cervical human papillomavirus infection: a longitudinal cohort study. Cancer Res. 2009;69:3828–32

Association of human papillomavirus type 58 with breast cancer in Shaanxi province of China.

A number of reports have identified HPV DNA in breast cancer specimens and HPV type 16, 18, 31, 33, 45, and 51 were more prevalent. HPV 58 was frequently detected in cervical cancer in Shaanxi China. The aim of the present study was to investigate whether HPV 58 present in breast cancer. 169 cases of breast cancer samples and 83 benign breast lesions were analyzed. Type specific primers and oligonucliotide probe were used for the detection of HPV 58 by conventional PCR and in situ hybridization techniques. The HPV 58 viral load were measured by qPCR. p16 protein expression were evaluated by immunohistochemistry. HPV 58 E7 DNA was detected in 25 out of 169 formalin fixed paraffin embedded breast cancer tissues (14.79%) by PCR, only 1 out of 83 non-malignant breast lesions showed positive (1.20%). The results of ISH showed that 17 out of 169 (10.06%) malignant samples were positive for HPV 58 E7, and only 1 out of 83 non-malignant lesions was positive. Positive p16 immunostaining was observed in all the HPV 58 E7 ISH positive cases, but 16 out of 98 cases with HPV negative were p16 positive. The presence of HPV 58 in both normal duct epithelial cells and carcinoma in situ along with its presence in the cancer cells of the same specimen indicated the possible causal role of HPV 58 in breast cancer. The findings provide a solid morphological evidence of the involvement of HPV 58 in breast cancer development.

Association of HPV types 6, 11, 16, and 18 DNA detection and serological response in unvaccinated adolescent women.

Antibodies directed against the human papillomavirus (HPV) L1 protein are detected in approximately 70% of individuals with HPV infections. The factors associated with a serological response are not characterized. It is hypothesized that the HPV viral load, duration of detection, or both would be associated with seropositivity in adolescent women. Adolescent women (n = 117), ages 15-17 at enrolment were followed for a mean of 6.2 years. Quarterly vaginal swabs (mean 22 per participant) were used to identify HPV 6, 11, 16, or 18 DNA (Roche PCR/Linear Array). Type-specific HPV infection was defined as ≥2 positive assays. To approximate viral load, Roche PCR/Linear Array test strips were scored visually based on the strength of signal relative to beta-globin controls. Sera collected near the end of study were tested by cLIA. Regression models were fit to assess associations between strength of signal (as represented by mean and cumulative strength of signal), duration of HPV detection, seropositivity, and serotiter. Detection of HPV DNA was associated with seropositivity for four types combined and for types 6, 16, and 18. Overall, 70.1% of DNA positive episodes were associated with type-specific seropositivity. The cumulative HPV DNA signal strength during periods of HPV detection for types 6, 11, 16, and 18 combined was associated with seropositivity (OR = 1.21, 95% CI 1.02-1.44 P = 0.026). No other HPV DNA predictors were found to be associated with seropositivity or serotiter.

Association of human papillomavirus type 16 long control region mutation and cervical cancer

BackgroundThe variation of human papillomavirus (HPV) genes or HPV variants demonstrates different risks of cervical cancer. Mutation in the long control region (LCR) at YY1-motifs is one of the mechanisms for enhancing viral oncogene expression during the course of cancer cell progression. In Thai women, cervical cancers are almost always associated with HPV16 variant sub-lineage Asian (HPV16As); however, the mechanism involved remains elusive. The aim of this study was to understand further the oncogenic potential of HPV16As.MethodsA total of 82 HPV16-positive specimens from Thai women were selected from formalin-fixed paraffin-embedded cervical tissues, and the full length E6 gene of each specimen was amplified and sequenced. LCRs of the HPV16As-positive cases were amplified and sequenced to analyze their polymorphisms. Transcriptional activities of the HPV16As LCRs were then compared with sub-lineage European (EUR), sub-lineage Asian-American 1 (AA1) and HPV16 prototype by insertion of the LCRs into the pGL3-Basic vector.ResultsThe HPV16 DNA sequences were classified as HPV16 prototype (18.3%), Asian (As, 61%), Asian American-1 (AA1, 8.5%), European (EUR, 7.3%), Asian African-2 (AFR2, 3.7%) and Java-135C (J135C, 1.2%). The prevalence of HPV16As was 30% in low-grade squamous intraepithelial lesion (LSIL), while that in high-grade squamous intraepithelial lesion (HSIL) and squamous cell cervical carcinoma (SCC) were 63.9% and 66.7%, respectively, which demonstrates a significant association of HPV16As with the disease severity. LCR polymorphisms from 43 HPV16As positive cases were analyzed by PCR-sequencing. Thirty-eight nucleotide variation positions spanned nucleotide positions 7157–82. Ten new mutations found in the HPV16As LCRs were located predominantly at the enhancer and proximal to the 3’-end of the early promoter. The LCRs of the common HPV16As, EUR and AA1 showed 5, 13 and 23-fold higher activity than the HPV16 prototype LCR, while those of the new nucleotide variations of As showed 19 (As-sv1) and 30 (As-sv14) -fold higher activity than the HPV16 prototype.ConclusionsHPV16As DNA sequence variation, especially at the proximal to early promoter in the LCR, enhances transcriptional activity. This could be one of the possible mechanisms for HPV16As-associated cervical cancer development.

Geographical distribution and oncogenic risk association of human papillomavirus type 58 E6 and E7 sequence variations

Human papillomavirus (HPV) 58 accounts for a notable proportion of cervical cancers in East Asia and parts of Latin America, but it is uncommon elsewhere. The reason for such ethnogeographical predilection is unknown. In our study, nucleotide sequences of E6 and E7 genes of 401 HPV58 isolates collected from 15 countries/cities across four continents were examined. Phylogenetic relationship, geographical distribution and risk association of nucleotide sequence variations were analyzed. We found that the E6 genes of HPV58 variants were more conserved than E7. Thus, E6 is a more appropriate target for type-specific detection, whereas E7 is more appropriate for strain differentiation. The frequency of sequence variation varied geographically. Africa had significantly more isolates with E6-367A (D86E) but significantly less isolates with E6-203G, -245G, -367C (prototype-like) than other regions (p ≤ 0.003). E7-632T, -760A (T20I, G63S) was more frequently found in Asia, and E7-793G (T74A) was more frequent in Africa (p < 0.001). Variants with T20I and G63S substitutions at E7 conferred a significantly higher risk for cervical intraepithelial neoplasia grade III and invasive cervical cancer compared to other HPV58 variants (odds ratio = 4.44, p = 0.007). In conclusion, T20I and/or G63S substitution(s) at E7 of HPV58 is/are associated with a higher risk for cervical neoplasia. These substitutions are more commonly found in Asia and the Americas, which may account for the higher disease attribution of HPV58 in these areas.

Elevated methylation of HPV16 DNA is associated with the development of high grade cervical intraepithelial neoplasia

We explored the association of human papillomavirus type 16 (HPV16) DNA methylation with age, viral load, viral persistence and risk of incident and prevalent high grade CIN (CIN2+) in serially collected specimens from the Guanacaste, Costa Rica cohort. 273 exfoliated cervical cell specimens (diagnostic and pre-diagnostic) were selected: (1) 92 with HPV16 DNA clearance (controls), (2) 72 with HPV16 DNA persistence (without CIN2+) and (3) 109 with CIN2+. DNA was extracted, bisulfite converted and methylation was quantified using pyrosequencing assays at 66 CpGs across the HPV genome. The Kruskal-Wallis test was used to determine significant differences among groups, and receiver operating characteristic curve analyses were used to evaluate how well methylation identified women with CIN2+. In diagnostic specimens, 88% of CpG sites had significantly higher methylation levels in CIN2+ after correction for multiple tests compared with controls. The highest area under the ROC curve (AUC) was 0.82 for CpG site 6457 in L1, and a diagnostic sensitivity of 91% corresponded to a specificity of 60% for CIN2+. Prospectively, 17% of CpG sites had significantly higher methylation in pre-diagnostic CIN2+ specimens (median time of 3 years before diagnosis) versus controls. The strongest pre-diagnostic CpG site was 6367 in L1 with an AUC of 0.76. Age-stratified analyses suggested that women older than the median age of 28 years have an increased risk of precancer associated with high methylation. Higher methylation in CIN2+ cases was not explained by higher viral load. We conclude that elevated levels of HPV16 DNA methylation may be useful to predict concurrently diagnosed as well as future CIN2+.

Human papillomavirus in invasive cervical cancer and cervical intraepithelial neoplasia 2 and 3 in Venezuela: A cross-sectional study

BackgroundThis study investigated the distribution of human papillomavirus (HPV) types in invasive cervical cancer (ICC), cervical intraepithelial neoplasia 2 (CIN2) and cervical intraepithelial neoplasia 3 (CIN3) in Venezuela. MethodsParaffin-embedded samples from 329 women from 29 medical centers of the 24 states of Venezuela were analyzed to determine the distribution of HPV types for ICC, CIN2, and CIN3, the prevalence of single and multiple infection, and the association of HPV types with severity of lesion, comparing CIN2 versus CIN3+ (CIN3 and ICC). The samples were analyzed with the polymerase chain reaction (PCR) followed by reverse hybridization for the identification of HPV types. ResultsHPV was identified in 95/96 ICC specimens (98.9%), in 142/149 CIN3 (95.3%) and in 78/84 CIN2 samples (92.8%). The most common types for ICC and CIN3 were: HPV16, 18, 31, and 33, and for CIN2 were HPV16, 31, 51, 52, and 18. HPV single infection was found in 82.1% of ICC cases, in 79.4% of CIN2 cases, and in 77.4% of CIN3 cases. HPV16 was identified as a single infection more frequently in women with CIN3+ than in those with CIN2 (68.6% versus 46.7%, P=0.002), and HPV16 or HPV18 types were more prevalent in CIN3+ than in CIN2 (73.4% versus 50%, P=0.0006). Conclusionthis is the first study of the distribution of HPV types in ICC, CIN2, and CIN3 conducted throughout the territory of Venezuela. HPV16 and HPV18 were the most frequent HPV types identified in single and multiple infections in both ICC and CIN3 groups, and are associated with severity of lesion. The knowledge of the distribution of HPV types would allow organization of an HPV-DNA-based screening test, and consideration of the implementation of prophylactic vaccination in Venezuela.

Association of human papillomavirus type 31 variants with risk of cervical intraepithelial neoplasia grades 2–3

Although the lineages of human papillomavirus type 31 (HPV31) variants are recognized, their clinical relevance is unknown. The purpose of our study was to examine risk of cervical intraepithelial neoplasia Grades 2-3 (CIN2/3) by HPV31 variants. Study subjects were women who participated in the atypical squamous cells of undetermined significance and low-grade squamous intraepithelial lesion Triage Study and who had HPV31 infections detected at one or more visits. They were followed semi-annually over 2 years for detection of HPV DNA and cervical lesion. HPV31 isolates were characterized by DNA sequencing and assigned into 1 of 3 variant lineages. CIN2/3 was histologically confirmed in 127 (27.0%) of the 470 HPV31-positive women, 83 diagnosed at the first HPV31-positive visit and 44 thereafter. The odds ratio for the association of 2-year cumulative risk of CIN2/3 was 1.7 (95% CI: 1.0-2.9) for infections with A variants and 2.2 (95% CI: 1.2-3.9) for infections with B variants as compared to those with C variants. Among women without CIN2/3 at the first HPV31-positive visit, the risk of subsequent CIN2/3 was 2.2-fold greater for those with A variants (95% CI: 1.0-4.8) and 2.0-fold greater for those with B variants (95% CI: 0.9-4.9) as compared to those with C variants. Similar associations were observed when CIN3 was used as the endpoint. The findings from our study help to tag HPV31 variants that differ in risk of CIN2/3 and to explain in part why some HPV31 infections regress spontaneously and others lead to disease progression.

Association of human papillomavirus types with recurrence in patients with condyloma acuminata

Objective To explore the distribution of human papillomavirus ( HPV ) types in patients with condyloma acuminatum ( CA ) and to investigate the association of viral types with recurrence of the disorder.Methods Electrocautery was performed in 130 patient to remove lesions with CA.The HybriMax was used to detect human HPV types in the skin lesion.After electrocautery,all the patients received intramuscular injections of BCG-PSN for two cycles.The incidence of recurrence and the HPV types of patients with recurrent CA were recorded within 6 months after treatment.Results The positive rate of HPV-DNA was 94.62％.13 types of HPV were detectable,of which low-risk HPV6 was 47.69％and HPV11 was 27.69％,accounting for a higher incidence rate.The muhiple infection rate was 24.62％.The recurrence rate of multiple infection with different HPV types was obviously higher than that of single infection ( 43.75％ vs.26.31％,P ＜ 0.05 ).Conclusions HPV-6 and HPV-11 were the main types of condyloma acuminatum infection in patients.Multiple HPV infection has a higher incidence rate and has a certain correlation with the recurrence of the disorder. Key words: Condyloma acuminatum; HPV-DNA; Prognosis; Recurrence

Transcriptome Sequencing Demonstrates that Human Papillomavirus Is Not Active in Cutaneous Squamous Cell Carcinoma

Beta-papillomavirus (β-HPV) DNA is present in some cutaneous squamous cell carcinomas (cuSCC), but no mechanism of carcinogenesis has been determined. We used ultra-high throughput sequencing of the cancer transcriptome to assess whether papillomavirus transcripts are present in these cancers. Sixty-seven cuSCC samples were assayed for β-HPV DNA by PCR, and viral loads were measured with type-specific qPCR. Thirty-one SCCs were selected for whole transcriptome sequencing. Transcriptome libraries were prepared in parallel from the HPV18 positive HeLa cervical cancer cell line and HPV16 positive primary cervical and periungual SCC. Thirty percent (20/67) of the tumors were positive for β-HPV DNA, but there was no difference in β-HPV viral load between tumor and normal tissue (p=0.310). Immunosuppression and age were significantly associated with higher viral load (p=0.016 for immunosuppression; p=0.0004 for age). Transcriptome sequencing failed to identify papillomavirus expression in any of the skin tumors. In contrast, HPV 16 and 18 mRNA transcripts were readily identified in primary cervical and periungual cancers and HeLa cells. These data demonstrate that papillomavirus mRNA expression is not a factor in the maintenance of cuSCC.

Association of Human Papillomavirus Type 16 E7 and HLA Class I Antigen Expression in Cervical Premalignant and Malignant Lesions

In the present experiment we studied the correlation between HPV16 infection and expression of HLA-I antigen in cervical premalignant and malignant lesions (cervicitis, CIN, cervical squamous carcinomas and adenocarcinoma samples). The HPV16 E7 DNA load and the expression of HLA-I antigen in the samples were measured by real-time fluorescence quantitative polymerase chain reaction (RFQ-PCR) and immunohistochemical S-P staining, respectively. Our data indicate that HPV16 E7 load was highly and positively associated with the development of cervical lesions (Spearman's correlation coefficient r=0.848, p<0.001), the negative rate of HLA-I antigen was significantly distinguished among groups (p<0.001), and HPV16 E7 infection and downregulation of HLA-I antigen were highly correlated in cervical lesions (Pearson's correlation coefficient r=-0.487, p<0.001). HPV16 E7 may play an important role in the downregulation of HLA-I antigen in cervical lesions, which results in the immune escape of the virus and the occurrence, development, invasion and metastasis of cancer. Furthermore, quantitative PCR for HPV16 E7 may play an important role in the early detection of cervical diseases and in guiding future therapy toward prevention.

Association of human papillomavirus type 16 E7 and HLA class I antigen expression in cervical premalignant and malignant lesions

In the present experiment we studied the correlation between HPV16 infection and expression of HLA-I antigen in cervical premalignant and malignant lesions (cervicitis, CIN, cervical squamous carcinomas and adenocarcinoma samples). The HPV16 E7 DNA load and the expression of HLA-I antigen in the samples were measured by real-time fluorescence quantitative polymerase chain reaction (RFQ-PCR) and immunohistochemical S-P staining, respectively. Our data indicate that HPV16 E7 load was highly and positively associated with the development of cervical lesions (Spearman's correlation coefficient r=0.848, p<0.001), the negative rate of HLA-I antigen was significantly distinguished among groups (p<0.001), and HPV16 E7 infection and downregulation of HLA-I antigen were highly correlated in cervical lesions (Pearson's correlation coefficient r=-0.487, p<0.001). HPV16 E7 may play an important role in the downregulation of HLA-I antigen in cervical lesions, which results in the immune escape of the virus and the occurrence, development, invasion and metastasis of cancer. Furthermore, quantitative PCR for HPV16 E7 may play an important role in the early detection of cervical diseases and in guiding future therapy toward prevention.

Characterization of neutralizing epitopes within the major capsid protein of human papillomavirus type 33

BackgroundInfections with papillomaviruses induce type-specific immune responses, mainly directed against the major capsid protein, L1. Based on the propensity of the L1 protein to self-assemble into virus-like particles (VLPs), type-specific vaccines have already been developed. In order to generate vaccines that target a broader spectrum of HPV types, extended knowledge of neutralizing epitopes is required. Despite the association of human papillomavirus type 33 (HPV33) with cervical carcinomas, fine mapping of neutralizing conformational epitopes on HPV33 has not been reported yet. By loop swapping between HPV33 and HPV16 capsid proteins, we have identified amino acid sequences critical for the binding of conformation-dependent type-specific neutralizing antibodies to surface-exposed hyper variable loops of HPV33 capsid protein L1.ResultsReactivities of monoclonal antibodies (mAbs) H33.B6, H33.E12, H33.J3 and H16.56E with HPV16:33 and HPV33:16 hybrid L1 VLPs revealed the complex structures of their conformational epitopes as well as the major residues contributing to their binding sites. Whereas the epitope of mAb H33.J3 was determined by amino acids (aa) 51–58 in the BC loop of HPV33 L1, sequences of at least two hyper variable loops, DE (aa 132–140) and FGb (aa 282–291), were found to be essential for binding of H33.B6. The epitope of H33.E12 was even more complex, requiring sequences of the FGa loop (aa 260–270), in addition to loops DE and FGb.ConclusionThese data demonstrate that neutralizing epitopes in HPV33 L1 are mainly located on the tip of the capsomere and that several hyper variable loops contribute to form these conformational epitopes. Knowledge of the antigenic structure of HPV is crucial for designing hybrid particles as a basis for intertypic HPV vaccines.

Association of human papillomavirus type 58 variant with the risk of cervical cancer.

Human papillomavirus (HPV) type 58 has been found to be prevalent among Chinese patients with cervical cancer. This study examined the oncogenic risk of HPV58 variants in Hong Kong, a southern part of China. Altogether, 1924 women were studied: 42.8% with a normal cervix, 16.2% with cervical intraepithelial neoplasia (CIN) I, 12.7% with CIN II, 20.8% with CIN III, and 7.6% with invasive cervical cancer (ICC). The overall prevalence of HPV58 was 11.4% (220) and increased statistically significantly with the severity of neoplasia (P(trend)<.001, chi(2) test for trend). Among HPV58-positive women, the occurrence of E7 632C-->T (T20I) and E7 760G-->A (G63S) variants (T20I/G63S) showed a positive trend of association with the severity of neoplasia (P(trend)<.001, chi(2) test for trend). HPV58 variants carrying these two substitutions showed an odds ratio (OR) for ICC of 26.79 (95% confidence interval = 10.14 to 74.72), and this OR was 6.9-fold higher than the ORs of variants without these substitutions. Patients with CIN III or ICC who were also infected with T20I/G63S variants had a statistically significant younger age at diagnosis than those infected with other variants (median age = 37 years versus 48 years; P =.038, two-sided Mann-Whitney U test). Thus, HPV58 variants carrying E7 T20I/G63S substitutions may be associated with an increased risk for cervical cancer.

Association of Human Papillomavirus Type 11 with Carcinoma of the Penis

Human papillomaviruses (HPVs) are epithelium-tropic viruses associated with several cutaneous, epithelial, and mucosal lesions. The oncogenic potential varies considerably among the more than 70 different genotypes so far identified. HPV 6 and 11 are generally found in benign genital condilomata or laryngeal papillomas, but they have been sporadically associated with genital malignancies. Polymerase chain reaction (PCR) primed by degenerated consensus oligonucleotides (from a late region of the HPV genome) allows one to amplify a broad spectrum of HPV, whereas the amplification with specific primers is restricted to a limited number of HPVs. Therefore, the restriction fragment length polymorphism assay permits one to identify the HPV type present in the PCR product. We report a case of an invasive verrucous carcinoma of the penis associated with HPV 11, a type previously considered noncarcinogenic.

Association of Human Papillomavirus Type 16 with Malignant Melanoma

We report a case of malignant melanoma associated with human papillomavirus (HPV) in a 37-year-old woman. The patient has had numerous brown papular and nodular tumors, 5 to 30 mm in diameter, on her left leg for > 15 years, some of them coalescing rapidly in the last 12 months to a multilobulated black nodule diagnosed as malignant melanoma by histology and immunohistochemistry. HPV type 16 DNA was detected in the melanoma specimen by reverse transcriptase polymerase chain reaction (rt-PCR) and in situ hybridization (ISH) of the tumor tissues. This is the first report of melanoma associated with HPV 16.