Genomic diversity of human papillomavirus (HPV) Genotype 38

Human papillomavirus (HPV) genotype HPV 38 is a HPV genotype associated with skin cancer and is classified taxonomically in the beta‐PV genus–species 2. At least six genomic variants of HPV 38, including prototype isolate and its subtype FA125, have been characterized so far. In order to investigate further the genomic diversity of HPV 38, a total of 39 HPV 38 positive samples obtained from hairs plucked from pubic, scrotal, perianal or eyebrow regions from 31 immunocompetent healthy male individuals were analyzed. The characterization of genomic variants was based on analysis of L1, E6, and E7 genomic regions. Sequence analysis revealed the presence of a single genomic variant in 35 samples and the presence of at least two different HPV 38 genomic sequences in four samples. A total of nine, nine, and five L1, E6, and E7 genomic variants were identified among 35 isolates, respectively. After combining nucleotide variations in all three genomic regions for a particular isolate, 13 different variants were identified, of which 6 and 7 corresponded to HPV 38 and FA125, respectively. In addition to 5 genomic variants identified previously (prototype isolate, subtype FA125, putative subtype AF091444, isolates U21875 and AF091443), 12 novel genomic variants were characterized. A sixth genomic variant described previously (L38917) was found to be identical with prototype HPV 38 isolate. Taking into account the results of this and previous studies, at least seventeen HPV 38 genomic variants exist today, 12 of which are described for the first time in this study. J. Med. Virol. 81:288–295, 2009. © 2008 Wiley‐Liss, Inc.     

Prevaccination genomic diversity of human papillomavirus genotype 11: a study on 63 clinical isolates and 10 full-length genome sequences

Prevaccination genomic diversity of human papillomavirus genotype 11 (HPV 11) was established by sequencing 40% of the genome of 63 clinical isolates obtained from an ethnogeographically closed Caucasian cohort, and full-length genome sequencing of the ten most divergent isolates. In the study, which included the largest number of isolates to date, by analyzing pooled L1, LCR, E6, E5a, and E5b sequences (3,217 bp) of an individual isolate, a total of 23 genomic variants were identified, of which three (5 isolates) and twenty (58 isolates) corresponded to prototypic and non-prototypic variant groups, respectively. Several novel, potentially important mutations are described. Full-length genome sequences of ten isolates revealed more than 99% similarity to the HPV 11 prototype isolate. The minimum genomic distance between the full-length sequences of genomic variants and the prototype was 3 point mutations and 2 inserts and the maximum distance 31 point mutations, one insertion and one deletion. Within the ethnogeographically closed cohort investigated in this study, HPV 11 was shown to be less polymorphic in comparison to the majority of HPV genotypes studied to date.     

Prevaccination genomic diversity of human papillomavirus genotype 6 (HPV 6)

Prevaccination genomic diversity of human papillomavirus genotype 6 (HPV 6) was established by sequencing 3798 bp of 77 clinically important HPV 6 isolates obtained from 45 and 32 patients with genital warts and laryngeal papillomas, respectively. By analyzing pooled L1, LCR, E6, E2, and E5 nucleotide data of an individual isolate, a total of 36 different genomic variants were identified, of which six (12 isolates), one (one isolate) and 29 (64 isolates) corresponded to HPV 6b, HPV 6a, and HPV 6vc genetic lineages, respectively. Several novel, potentially important mutations were identified. Non-prototypic HPV 6vc genomic variants were found in the majority of genital warts and laryngeal papillomas included in the study. The presence of serious HPV 6 genome sequence errors was confirmed and novel sequence errors were identified in sequence repositories.     

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.     

Immunohistochemical detection of p53 protein in cutaneous lesions from transplant recipients harbouring human papillomavirus DNA

Human papillomaviruses (HPV) are thought to be involved in the malignant evolution of cutaneous lesions from transplant recipients. As E6 proteins from potentially oncogenic HPV types degradep53 tumour suppressor gene product in vitro, we analysed p53 protein status in benign, premalignant and malignant skin lesions from grafted patients, to determine whether HPV may interfere with p53 function. With immunohistochemistry, p53 protein accumulation was detected in 70% of skin lesions from grafted patients. p53 immunoreactivity was confined to basal keratinocytes in benign lesions (warts, condylomas), while suprabasal keratinocytes were also stained in premalignant and malignant skin lesions (precancerous keratoses, squamous cell carcinomas). Multiple HPV carriage was detected with in situ hybridization in benign and malignant skin lesions from transplant recipients: low risk HPV types 1, 2, 6, 11 and potentially oncogenic HPV types 5, 16, 18 were frequently found. There was no clear correlation between p53 detection and the presence of the HPV types under study. The frequent detection of p53 protein in cutaneous lesions from grafted patients is suggestive of p53 protein accumulation interfering with normal function. Our results may reflect the presence of mutated p53 proteins due to the mutagenic effect of ultra-violet (UV), or wild-type p53 protein accumulation in response to UV-induced DNA damage, or may be produced by the interaction with HPV-encoded E6 proteins.     

Genetic diversity of human papillomavirus type 16 E6, E7, and L1 genes in Italian women with different grades of cervical lesions

High‐risk human papillomaviruses (HPVs) are risk factors for the development of cervical cancer. HPV 16 is the most common type, being present in about 60% of cervical cancers worldwide. Previous studies have reported upon the association between HPV 16 E6 variants and increased risk of cervical intraepithelial neoplasia and invasive cervical cancer. In this study, the presence of HPV 16 polymorphisms in the E6, E7, and L1 genes was investigated in relation to the presence of high‐grade lesions. Sequencing of the E6 gene revealed the presence of nucleotide mutations resulting in 15 amino acid changes. Of these, the G134D and C136R fall within the CXXC zinger finger domain important for p53 binding. In the E7 gene, four nucleotide variations were identified with two leading to the amino acid substitutions L15V and S31R. The L1 gene showed 13 nucleotide changes leading to 11 amino acid substitutions. Among these, the R364C and N367D are located at the base of the HI‐loop of the L1 protein, considered to be the immunodominant epitope of HPV 16. No significant relationship between HPV 16 variants and high‐grade lesions was found. Phylogenetic analysis showed that all the HPV 16 variants identified belonged to the European lineage, except one which was of the Asian‐American lineage. The European‐350G variant was detected most frequently (22 of 34, 64.7%). The study provides some new data on the genetic diversity of HPV 16 which may help to understand the oncogenic potential of the virus and to improve management of patients. J. Med. Virol. 81:1627–1634, 2009. © 2009 Wiley‐Liss, Inc.     

Prevalence of infection with high-risk human papillomavirus in women in Colombia

The prevalence of human papillomavirus (HPV) infections in 2109 females inhabiting five cities of Colombia was determined. Of the 49.2% with an HPV infection, 59.8% were infected with more than one viral type. Species 7 (of the the genus Alphapapillomavirus ) was associated with multiple infections. Analysis of the socio-demographic data revealed a statistically significant protective effect associated with the status of civil union (civil recognition of cohabitation without marriage), and indigenous ethnicity proved to be a risk factor for HPV infection. This is the first study comparing HPV infection among women from geographical regions of Colombia with different socio-cultural structures.     

Tumor-specific and gender-specific pre-vaccination distribution of human papillomavirus types 6 and 11 in anogenital warts and laryngeal papillomas: a study on 574 tissue specimens

Anogenital warts and laryngeal papillomas are two most important benign tumors etiologically linked with HPV. In the study, which included both the largest number of laryngeal papilloma tissue specimens (152 specimens from 152 patients) to date and the largest number of prospectively collected and histologically confirmed tissue specimens of anogenital warts obtained from both genders (422 specimens from 315 patients), HPV DNA was detected in 413/422 (97.9%) of anogenital warts and 139/152 (91.4%) of laryngeal papillomas. HPV‐6 and/or HPV‐11 were detected in 291/315 (92.4%) patients with anogenital warts and in 138/152 (90.8%) patients with laryngeal papillomas, indicating that the great majority of both tumors could be prevented with prophylactic quadrivalent vaccine. The HPV‐6 gender‐specific distribution in both anogenital warts and laryngeal papillomas was not statistically significant. In contrast, HPV‐11 was found almost three times more often in males than in females with anogenital warts (16.5% vs. 6.3%; P = 0.008), with a gender neutral HPV‐11 type distribution in laryngeal papillomas. The overall HPV DNA prevalence in anogenital warts was significantly different from that in laryngeal papillomas (97.1% vs. 91.4%; P = 0.01). In the first comparison of the HPV‐6/HPV‐11 type‐specific distribution between patients suffering from anogenital warts and laryngeal papillomas with the same geographic and ethnic background, a significant imbalance in tumor‐specific distribution of HPV‐6 and HPV‐11 was identified: HPV‐6 was statistically more often present in anogenital warts than in laryngeal papillomas (79.0% vs. 59.2%; P = 0.000013), whereas HPV‐11 was statistically more frequent in laryngeal papillomas than in anogenital warts (28.9% vs. 12.4%; P = 0.00003). J. Med. Virol. 84: 1233–1241, 2012. © 2012 Wiley Periodicals, Inc.     

High prevalence of intermediate-risk human papillomavirus infection in uterine cervices of Kenyan women infected with human immunodeficiency virus

The aim of this study was to investigate an association between certain human papillomavirus (HPV) types and human immunodeficiency virus (HIV) infections. Sexually active females (n = 487; 19-61 years old) were enrolled in the study. Subjects underwent Pap testing and evaluations of HIV and HPV infection status on uterine cervical cell samples. HPV genotyping was performed using a Kurabo GeneSQUARE DNA microarray test. Overall, 23 HPV genotypes were detected, and the most prevalent HPV genotype was HPV-52, followed by HPV-39, -54, -45, -56, -53, -31, -42, -16, -68, and -51. HPV-30, -53, -54, -61, and -66, which are associated with abnormal cytology, are categorized as intermediate-risk in this study. Detection of both high- and intermediate-risk HPV types was significantly associated with cervical abnormality and HIV infection. Multivariate analysis revealed that some high-risk HPV types (HPV-31, -45, -51, -56, and -59) and most intermediate-risk HPV types were associated with HIV infection, while the high-risk types (HPV-16, -18, -33, -35, -39, -52, -58, and -68) were not. The oncogenic effect of the most malignant HPV types (e.g., HPV-16 and -18) appear to be lower, while that of intermediate-risk types are greater, in areas with a high prevalence of HIV infection.     

Population-based type-specific prevalence of high-risk human papillomavirus infection in middle-aged Swedish women

Human papillomavirus (HPV) DNA testing can be used to identify women at risk of the development of cervical cancer. The cost-effectiveness of HPV screening is dependent on the type-specific HPV prevalence in the general population. The present study describes the prevalence and spectrum of high-risk HPV types found in a large real-life population-based HPV screening trial undertaken entirely within the cervical screening program offered to middle-aged Swedish women. Cervical brush samples from 6,123 women aged 32-38 years were analyzed using a general HPV primer (GP5+/6+) polymerase chain reaction-enzyme immunoassay (PCR-EIA) combined with reverse dot-blot hybridization for confirmation and HPV typing by a single assay. In this study, 6.8% (95% CI 6.2-7.5) (417/6,123) were confirmed as high-risk HPV positive. Infections with 13 different high-risk HPV types were detected, of which HPV 16 was the most prevalent type (2.1%; 128/6,123), followed by HPV 31 (1.1%; 67/6,123). Any one of the HPV types 18, 33, 35, 39, 45, 51, 52, 56, 58, 59, or 66 was detected in 3.6% (223/6,123) of the women. Infection with two, three, and five types simultaneously was identified in 32, 5, and 1 women, respectively. The combination of PCR-EIA as a screening test and reverse dot-blot hybridization as a confirmatory test, was found to be readily applicable to a real-life population-based cervical screening. The type-specific HPV prevalence found support in previous modeling studies suggesting that HPV screening may be a favorable cervical screening strategy.     

Low-level persistence of human papillomavirus 16 DNA in a cohort of closely followed adolescent women

Most human papillomavirus (HPV) infections in young women become undetectable by standard assays after a few months. It is possible that many HPV infections do not actually clear, but persist at very low levels for years, becoming detected again later in life. The purpose of this study is to describe HPV 16 clearance, reappearance, and low‐level persistence in a cohort of adolescent women. Adolescent women (N = 66), not vaccinated against HPV, were recruited from 1998 to 2008 into a longitudinal study. Self‐collected vaginal samples were obtained quarterly and tested for HPV by Linear Array HPV Genotyping Test (LA‐HPV). To explore low‐level persistence, a type‐specific nested PCR for HPV 16 (TSN‐PCR‐16) was developed. Women with HPV 16 detected by LA‐HPV had their negative swabs retested with TSN‐PCR‐16. Forty‐two participants with HPV 16, followed for a mean of 6.3 years, were analyzed. Using LA‐HPV, the median duration of HPV 16 detection was 428 days (SD 852.5 days). TSN‐PCR‐16 detected HPV 16 during periods of LA‐HPV non‐detection in samples from many women. Using a combination of LA‐HPV and TSN‐PCR‐16 results, the median duration of HPV 16 detection was 1,022.5 days (SD 943.7 days). The durations of detection differed significantly between the two methods (P = 0.0042) with a mean difference of 434.5 days. In adolescent females, duration of HPV 16 detection was significantly longer when TSN‐PCR‐16 was combined with LA‐HPV. Some apparently cleared HPV 16 could be shown to persist at low levels using nested PCR. J. Med. Virol. 83:1362–1369, 2011. © 2011 Wiley‐Liss, Inc.     

Prevalence and genotype distribution of human papillomavirus in women living with HIV/AIDS in an area of Northeast Brazil

Women infected by human immunodeficiency virus (HIV) are more likely to manifest oncogenic viral infections including human papillomavirus (HPV). It was investigated the HPV prevalence, genotype distribution and HPV relationship with cervical lesions among women living with HIV in Sergipe state, Northeast Brazil. A prevalence survey was conducted including 270 HIV-infected women who attended the reference center for HIV in Sergipe from August 2014 to November 2017. Cervical samples were processed by the polymerase chain reaction for HPV-DNA detection. Among the 270 HIV-infected women, 190 (70.4%) were between 26 and 49 years old and 159 (55.6%) were coinfected with HPV. Among the coinfected women, 24 viral types were identified; 113 (72%) subjects had high-risk HPV types, and the most prevalent was HPV 16 (53/35.3%). Positive HPV status was statistically associated with having 0 to 8 years of schooling compared with ≥9 years of schooling; and have been diagnosed with HIV infection less than 5 years ago compared with more than 10 years. Cytological abnormalities were found in 13.4% (31/231) of women, most with high-grade squamous intraepithelial lesions (16/51.6%). However, of women who had no cytological lesions or malignancy (200/86.6%), almost half were HPV DNA-positive (99/49.5%). In conclusion, the prevalence of HPV among women living with HIV in Sergipe was high. There was a high frequency of high-risk HPV infection, and a wide diversity of genotypes were detected, with HPV 16 being the most frequent.     

Prevalence of human papillomavirus infection in Argentinean women attending two different hospitals prior to the implementation of the National Vaccination Program

Cervarix vaccine was included in the National Immunization Program of Argentina in 2011 but data about the local distribution of human papillomavirus (HPV) infection in women exposed to the virus are scarce. This cross‐sectional study determined the prevalence and type distribution of HPV infection in unvaccinated women attending routine gynecological screening in two public hospitals located in Buenos Aires and Santa Fe, Argentina. Socio‐demographic, sexual behavior, and co‐factors information was obtained from all participants (Buenos Aires, n = 429; Santa Fe, n = 433). Cervicovaginal swabs were tested with an MY11/09 primer‐based assay and with the CUT primer system targeting mucosal/cutaneous HPVs. Participants from Buenos Aires showed significantly higher rates of HPV infection (52.4% vs. 40.6%), of multiple infections (24.2% vs. 16.4%), and of low‐risk (20.3% vs. 13.9%) and high‐risk types (44.1% vs. 33.3%) than those from Santa Fe. HPV‐66 (Buenos Aires: 17%) and HPV‐16 (Santa Fe: 8.5%) were the most prevalent types. Novel HPV‐66 putative subtype and variants were identified. Vaccine types 16 and 18 were frequent (Buenos Aires: 13.5%; Santa Fe: 10.2%) but few participants had co‐infections with both (Buenos Aires: 1.4%; Santa Fe: 0.2%). A common risk factor for HPV infection was having a new sexual partner in the last year (Buenos Aires: OR 2.53, P < 0.001; Santa Fe: OR 1.85, P = 0.04). This study provides valuable baseline data for future assessment of the impact of massive vaccination in Argentina and it underlines the use of additional HPV testing strategies, such as the CUT system, for surveillance and vaccinology. J. Med. Virol. 85:655–666, 2013. © 2013 Wiley Periodicals, Inc.