Oral antibodies to human papillomavirus type 16 in women with cervical neoplasia

This study investigated the relationship between human papillomavirus type 16 (HPV-16) antibodies detected in oral fluid from women with cervical neoplasia, their HPV-16 antibody seroprevalence, and their cervical HPV-16 DNA presence. Cervical HPV-16 DNA was detected by polymerase chain reaction in 43.2% (35/81) of these women. The prevalence of IgG and IgA antibodies to HPV-16 virus-like particles (VLP-16) in oral fluid and was investigated by enzyme-linked immunosorbent assay. Anti-VLP-16 IgA antibodies were detected in oral fluid from 54.3% (44/81) of women with cervical neoplasia, compared with 8% (3/36) in controls (P = 0.000002). Anti-VLP-16 IgG was detected in oral fluid from 43.2.9% (25/72) and 13.3% (4/30; P = 0.029), respectively. Women who were HPV-16 DNA positive at their cervical lesion, displayed an oral fluid anti-VLP-16 IgA prevalence of 60.7% (17/28) and HPV-16 DNA negative women an oral fluid anti-VLP-16 IgA prevalence of 50% (20/40; P = 0.38). Oral fluid anti-VLP-16 IgG prevalence in HPV-16 DNA positive women was 28.6% (8/28) compared with 40% (16/40) in oral fluid from HPV-16 DNA negative women (P = 0.3). Amongst HPV-16 DNA positive women, the anti-VLP-16 IgG seroprevalence was 75% (21/28) and IgA seroprevalence 35.7% (10/28) and for the HPV-16 DNA negative women these values were 60% (24/40) and 32.5% (13/40), respectively. Oral IgA antibody testing proved no more sensitive than serum antibody detection for the determination of HPV infection but could be useful as a non-invasive screening method for women with cervical neoplasia and for estimating the mucosal antibody response to HPV vaccines.     

Human papillomavirus type 16 variants in cervical cancer from an admixtured population in Brazil

Several studies indicate that molecular variants of HPV-16 have different geographic distribution and risk associated with persistent infection and development of high-grade cervical lesions. In the present study, the frequency of HPV-16 variants was determined in 81 biopsies from women with cervical intraepithelial neoplasia grade III or invasive cervical cancer from the city of Belem, Northern Brazil. Host DNAs were also genotyped in order to analyze the ethnicity-related distribution of these variants. Nine different HPV-16 LCR variants belonging to four phylogenetic branches were identified. Among these, two new isolates were characterized. The most prevalent HPV-16 variant detected was the Asian-American B-2, followed by the European B-12 and the European prototype. Infections by multiple variants were observed in both invasive cervical cancer and cervical intraepithelial neoplasia grade III cases. The analysis of a specific polymorphism within the E6 viral gene was performed in a subset of 76 isolates. The E6-350G polymorphism was significantly more frequent in Asian-American variants. The HPV-16 variability detected followed the same pattern of the genetic ancestry observed in Northern Brazil, with European, Amerindian and African roots. Although African ancestry was higher among women infected by the prototype, no correlation between ethnical origin and HPV-16 variants was found. These results corroborate previous data showing a high frequency of Asian-American variants in cervical neoplasia among women with multiethnic origin.     

子宫颈癌、子宫颈上皮内病变组织中SIRT1、HPV 16/18E6的表达及其意义

目的检测子宫颈癌及癌前病变中SIRT1的表达情况,探讨其与临床病理特征的关系。同时检测早期癌蛋白中HPV16/18E6的表达,分析两者的相关性。方法应用免疫组化En Vision法检测30例子宫颈炎、100例子宫颈上皮内病变(高级别、低级别各50例)、30例子宫颈鳞状细胞癌组织中SIRT1和HPV 16/18E6的表达。结果子宫颈癌组织中SIRT1阳性率为93.33%(28/30),高于子宫颈炎组织(13.33%,4/30),差异有统计学意义(P0.05)。子宫颈高级别上皮内病变SIRT1阳性率(88%,44/50)高于低级别上皮内病变(14%,7/50),差异有统计学意义(P0.05)。但高级别上皮内病变与子宫颈癌SIRT1阳性率差异无统计学意义(P0.05);低级别上皮内病变与子宫颈炎中SIRT1阳性率差异无统计学意义(P0.05)。在子宫颈癌中,SIRT1的阳性率与临床分期和组织学分级有关,晚期、分化差的子宫颈癌阳性率高于早期、分化好的子宫颈癌,差异有统计学意义(P0.05)。在子宫颈癌中SIRT1的阳性率(93.33%,28/30)高于HPV 16/18E6(30%,9/30),在子宫颈高级别上皮内病变中SIRT1的阳性率(88%,44/50)高于HPV 16/18E6(28%,14/50),但在低级别上皮内病变中SIRT1的阳性率(14%,7/50)低于HPV 16/18E6(36%,18/50),两者差异有统计学意义(P0.05)。结论 SIRT1的阳性率随着病变程度增加而升高,提示SIRT1与细胞恶性转变有关,其过表达可能促进上皮向高级别内病变乃至子宫颈癌进展。     

Analysis of human papillomavirus type-16 variants in Italian women with cervical intraepithelial neoplasia and cervical cancer

Human papillomavirus type 16 (HPV-16) classes (E, AA, As, Af1, Af2) and their variants have different geographic distribution and different degrees of association with cervical lesions. This study was designed to examine HPV-16 variants among Italian women and their prevalence in case patients (affected by invasive cervical carcinoma or cervical intraepithelial neoplasia grade 2-3 and cervical intraepithelial neoplasia grade 1), versus control subjects with normal cervical epithelium (controls). A total of 90 HPV-16 positive cervical samples from women of Italian Caucasian descent have been tested, including 36 invasive cervical carcinomas, 21 with cervical intraepithelial neoplasias grade 2-3, 17 with cervical intraepithelial neoplasia grade 1 and 16 controls. HPV-16 was detected with an E6/E7 gene-specific polymerase chain reaction, and variant HPV-16 classes and subclasses were identified by direct nucleotide sequencing of the region coding for the E6 and the E7 oncoproteins, the MY09/11-amplified highly conserved L1 region, and the long control region (LCR). Among the 90 HPV-16 samples, nine viral variants have been identified belonging to the European (Ep-T350 and E-G350) and non-European (AA and Af-1) branches. The E-G350 is the prevalent variant in all analyzed different disease stages being present in 55.5% of ICC, 52.4% of cervical intraepithelial neoplasias 2-3, 47.1% of cervical intraepithelial neoplasia grade 1, and 50.0% of control samples. The non-European variants AA and Af1, rarely detected in control samples, represent 33.3% of all HPV-16 infections in invasive cervical carcinoma (with a peak of 19.4% and 13.9%, respectively), showing a statistically significant increase in frequency in more advanced lesions (chi(2) trend = 7.2; P < 0.05). The prevalence of HPV-16 Ep-T350, however, is higher in controls (43.7%) and in of cervical intraepithelial neoplasia grade 1 (41.2%) than in cervical intraepithelial neoplasia grade 2-3 (28.6%) and in invasive cervical carcinoma (11.1%) cases strongly suggesting lack of progression for pre-neoplastic lesions associated with such variant. The increased frequency of non-European variants in invasive lesions suggests that they are more oncogenic than European variants. This could have implications for future diagnostic and therapeutic strategies.     

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.     

Sequence variation of human papillomavirus type 16 E7 in preinvasive and invasive cervical neoplasias

Variation in the nucleotide sequence of the HPV 16 E7 gene in preinvasive cervical intra-epitherial neoplasia (CIN) and invasive cervical carcinoma specimens was analyzed. Direct DNA sequencing of PCR-amplified products with primers different from those used for PCR with 5-end labeling generated distinct sequence ladders with a low background, even in specimens containing relatively low copy numbers of HPV. Of 14 cervical neoplasias, 11 cases showed sequence diversity from prototype HPV16, and a total of 22 nucleotide exchanges were detected. Nine of these led to single amino acid exchanges: [Thr⁵] to [Lys⁵] in one case and [Asn²⁹] to [Ser²⁹] in eight cases. The [Ser²⁹] E7 was distributed uniformly among invasive carcinomas and precancerous legions, and was also found in a normal cervix. The [Lys⁵] E7 and [Ser²⁹] E7 had transforming potential similar to the prototype E7 assessed by cooperation with the activatedras gene in rat embryo fibroblasts.     

A pilot study on the distribution of human papillomavirus genotypes and HPV-16 variants in cervical neoplastic lesions from Ecuadorian women

Human papillomaviruses (HPVs) are the cause of cervical intraepithelial neoplasia and invasive carcinomas of the uterine cervix. The distribution of specific HPV genotypes varies greatly across populations and HPV surveys have been performed in different geographical regions in order to apply appropriate vaccine strategies. The aim of this study was to determine the spectrum of HPV genotypes and HPV-16 variants among women with cervical lesions living in Ecuador. A total of 71 cases have been analyzed, including 32 chronic cervicitis, 29 cervical intraepithelial neoplasia grade 1, and 10 cervical intraepithelial neoplasia grade 2-3. HPV sequences were detected by broad spectrum consensus-primer-pairs MY09/MY11 and GP5+/GP6+-based polymerase chain reaction and characterized by nucleotide sequence analysis. Overall, 31 (43.7%) cases were HPV positive with prevalence rates of 37.5%, 44.8%, and 60% in patients with chronic cervicitis, cervical intraepithelial neoplasia grade 1 and cervical intraepithelial neoplasia grade 2-3, respectively. Among the positive cases, the most common genotypes were HPV 16 (64.5%) and HPV 81 (29%) followed by HPV 31, 53, 56, and 58, in descending order of prevalence. Seventeen (85%) HPV-16 isolates were classified as European and three (15%) as African-1 variant on the basis of nucleotide signature present within the MY09/MY11 L1 sequence. The results suggest that HPV 16 has a very high prevalence among women with cervical lesions in Ecuador; therefore, an effective HPV-16 based vaccine should prevent the development of cervical cancer in a large proportion of Ecuadorian women.     

Genotyping of human papillomavirus in paraffin embedded cervical tissue samples from women in ethiopia and the Sudan

Cervical cancer is the most frequent female malignancy in most developing countries. Previous studies have demonstrated a strong association of human papillomavirus (HPV) infection with dysplasia and carcinoma of the uterine cervix. The objective of this study was to identify the prevailing HPV genotypes responsible for the development of cervical cancer among women in Ethiopia and the Sudan. A molecular characterization of HPV was done on 245 paraffin embedded cervical biopsy samples collected from the two countries. Amplification of HPV and subsequent genotyping was done using SPF10 primers and Line probe assay. Of samples collected from Ethiopian patients, 93% (149/160) and 13% (21/160) had high risk and low risk HPV genotypes, respectively. Among samples collected from the Sudan, 94% (80/85) harbored high risk and 11.7% (10/85) low risk HPV genotypes. Human papillomavirus 16 was the most frequent genotype identified in samples from Ethiopia (91%, 136/149) and the Sudan (82.5%, 66/80). HPV 52, 58, and 18 were the second, third and fourth common genotypes identified in Ethiopia, whereas HPV 18, 45, and 52 were the second, third, and fourth genotypes identified in samples collected from the Sudan. Thus, individuals living in different geographical localities should receive vaccines based on the specific genotypes circulating in the area and a vaccine targeting HPV 16, 18, 45, 52, and 58 may be optimal for the control of cervical cancer in the two countries. J. Med. Virol. 85:282–287, 2013. © 2012 Wiley Periodicals, Inc.     

Codon 72 polymorphism of p53 and HPV type 16 E6 variants as risk factors for patients with squamous epithelial lesion of the uterine cervix

The Arg/Arg genotype versus Arg/Pro or Pro/Pro at codon 72 of the p53 gene in association with human papillomavirus (HPV) 16 E6 variants has been implicated as a risk marker in cervical neoplasia. However, research on this topic has produced controversial results. The association of p53 codon 72 polymorphism alone and in combination with specific HPV 16 E6 variants with risk of developing squamous intraepithelial cervical lesion has been investigated in low and high‐grade squamous intraepithelial lesions and in HPV‐negative controls from an Italian population. The data obtained showed statistically significant different distribution of p53 genotypes between healthy controls and precursor lesions, with the p53 arginine homozygous increased in high‐grade squamous intraepithelial lesions. The T350G HPV 16 variant was the most frequent variant observed in the analyzed group of Italian women, showing a slight decreasing with the severity of the lesion. At the same time, the number of the prototype T350 slightly increased with the severity of the cytological lesions. In conclusion, p53 arginine homozygous was found to be increased in high‐grade lesions, supporting the results of previous investigations indicating that HPV‐positive patients with p53 Arg/Arg have an increased risk of developing pre‐cancerous lesions. In addition, T350G HPV 16 variant was over‐represented in p53 Arg homozygous women with cervical lesions. When p53 genotype and HPV 16 variants are considered together, no difference emerges between cases and controls so is not possible to assess that the oncogenic effect of HPV 16 T350G variant may be influenced by the p53 genotype. J. Med. Virol. 85:83–90, 2012. © 2012 Wiley Periodicals, Inc.     

Distinctive distribution of HPV16 E6 D25E and E7 N29S intratypic Asian variants in Korean commercial sex workers

The distribution of HPV16 sequence variations differs geographically and specific HPV16 E6 and E7 variants might carry a high risk for development of invasive cervical cancer and cervical intraepithelial neoplasia in a given population. To investigate the genetic variation of HPV 16 E6 and E7 genes, genomic DNAs from 56 HPV16-infected commercial sex workers were extracted from their cervical swabs by using DNA isolation kit. The E6 and E7 coding region (34-880) with HPV16 E6/E7 specific PCR were amplified and analyzed by using the DNAstar software. At the nucleotide level, 26 variants of the HPV16 E6 and E7 genes were identified including 12 silent mutations. At the amino acid level, the isolates showed 14 variants including E6 Q14H, E6 D25E, E6 I27R, E6 H78Y, E6 L83V, and E7 N29S. The dominant HPV16 E6 and E7 variants were HPV16 E6 D25E (68%) and HPV16 E7 N29S (73%), respectively, which belong to Asian lineage. Although this study has some limitations such as a small sample size and not enough clinical data, these finding suggests that the distinctive distribution of HPV 16 As-variant E6 D25E and E7 N29S might be associated with geographical dependence rather than disease progression. Further study is needed to determine the clinical and biological effects of these variants.     

Activities of human papillomavirus 16 E6 natural variants in human keratinocytes

Genetic variations in the E6 oncogene have been associated with different risk for cancer progression. In the present study, the functional significance of human papillomavirus (HPV) polymorphism in the E6 oncogene was investigated. Ten HPV16 E6 variants containing amino acid substitutions in the N-terminal region of E6 were evaluated for different biological and biochemical activities in human keratinocytes, the target cells for HPV infection. Western blot analyses of primary foreskin human keratinocytes or immortalized human keratinocytes, stably transduced with the E6 variants, revealed reduced p53 and Bax levels in all E6 expressing cultures. The reduction induced by most E6 proteins was at similar levels and comparable to the reduction induced by the E6 prototype. The ability of the proteins to induce serum/calcium-differentiation resistant colonies in primary keratinocytes was more variable. Overall activities of the variants ranged between 0.24- and 2.18-fold of the E6 prototype activity. The I27R/L83V variant showed the lowest activity whereas the R8Q variant showed the highest activity. The L83V polymorphism previously associated with risk for cancer progression in some populations, showed significant activity, comparable to that of the E6 prototype, in reducing p53 and Bax levels. Furthermore, this variant showed enhancement in the ability to induce colonies resistant to serum/calcium-triggered differentiation, however, the difference from the prototype was not statistically significant. This, and augmentation of other described functions might result in differences in L83V pathogenicity.     

Lineage analysis of human papillomavirus type 18 based on E6 region in cervical samples of Iranian women

Distinct human papillomavirus (HPV) 18 variants are thought to differ in oncogenic potential and geographic distribution. As such, understanding the regional variants of HPV 18 would be of great importance for evolutionary, epidemiological, and biological analysis. In this regard, the sequence variations of E6 gene were investigated to characterize more common variants of HPV 18 in normal cells, premalignant, and malignant samples collected from the cervix. In total, 99 samples of HPV 18 were analyzed by polymerase chain reaction and sequencing. In overall, lineages A was identified in all study subjects, among which sublineage A4 was dominant although the difference observed was not statistically significant with regard to different stages of disease. Sublineage A4 comprised 90.9% of samples and the remaining were belonged to sublineages A1, A2, A3, and A5 at the frequency of 6.1%, 1%, 1%, and 1%, respectively. In conclusion, our findings clearly highlight the sublineage A4 of HPV 18 as the most dominant variant in Iran.     

宫颈癌HPV16,18 DNA定量分析

目的为了研究HPV16/18病毒载量与宫颈癌危险性的关系.方法 FQPCR用于HPVDNA的检测,卡方检验用于阳性率的分析,t检验用于病毒DNA量的分析.结果宫颈癌妇女高危型阳性率显著高于湿疣组妇女;病毒载量也显著高于后者.结论宫颈癌与高危型HPV感染相关,随病毒载量增加致癌危险性增大.