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.     

Human papillomavirus type 16 variants isolated from vulvar Bowenoid papulosis

Tissues from two cases of Bowenoid papulosis of the vulva were found to contain human papillomavirus (HPV) 16 DNA by Southern blot hybridization. Analysis of the hybridization pattern revealed differences in a restriction fragment of one specimen as compared to the HPV 16 DNA prototype. To investigate if these differences could interfere with the expression of such oncogenic viral genomes, the corresponding DNA fragments were cloned and further analyzed. After amplification by PCR and DNA sequencing, a 213 base pairs duplication was mapped in the long control region (LCR) of this HPV 16 variant. One single PCR fragment was obtained from the other Bowenoid papulosis, which is identical in size with the same region in the HPV-16 prototype. The duplication in the HPV-16 LCR analyzed in this study maps upstream of a region containing several regulatory elements.     

p16 expression in relation to human papillomavirus in anogenital lesions

Recent studies have revealed that cervical cancers associated with high-risk human papillomavirus (HPV) showed overexpression of the p16 protein, a cyclin-dependent kinase inhibitor. The expression of this cell cycle regulator in lesions of the anogenital region in association with HPV physical status (episomal or integrated) has not been studied at the present time. In this report, immunohistochemical analysis of p16 and HPV detection by in situ hybridization were performed on 110 formalin-fixed and paraffin-embedded samples of anogenital lesions. The results showed strong diffuse p16 staining in all integrated high-risk HPV-positive lesions, whereas most episomal HPV-positive lesions or HPV-negative lesions showed no p16 immunostaining. However, there were a few HPV-negative lesions or lesions with episomal HPV harboring p16 overexpression. On the other hand, some lesions were p16 negative while showing the presence of high-risk HPV in its episomal form. In conclusion, screening for p16 overexpression in cutaneomucous lesions of the anogenital region allowed good discrimination between HPV-integrated lesions and lesions harboring episomal HPV or no HPV. But p16 overexpression was not always predictive of the presence of high-risk HPV; moreover, absence of p16 immunostaining observed in some high-risk HPV lesions suggested that limiting the screening to p16 would exclude some patients harboring high-risk HPV from any follow-up.     

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.     

Molecular variants of human papillomavirus type 16 and 18 and risk for cervical neoplasia in Portugal

Persistent high-risk human papillomavirus (HPV) infection is considered as the central cause of invasive cervical cancer. Specific HPV 16 and 18 sequence variations were associated with an increased risk for progression. The purpose of this study was to analyze intratypic variations of HPV 16 and 18 within the E6 gene, MY09/11 and LCR regions, and to evaluate the risk of these variants for cervical neoplasia among Portuguese women. Cervical samples from 187 HPV 16-positive and 41 HPV 18-positive women with normal epithelium, cervical intraepithelial neoplasia, or invasive cervical cancer were amplified by type-specific PCR, followed by sequence and phylogenetic analysis. Sixteen new HPV 16 and 18 patterns are described in this paper. European HPV 16 variants were the most frequent (74.3%), particularly Ep-T350 (44.4%), followed by African (16.1%), and Asian-American (9.6%). Non-European HPV 16 variants were more frequent in pre-invasive lesions than in normal tissue and low-grade lesions. However, when analyzed separately, only African variants were associated significantly with an increased risk for cervical cancer. For HPV 18, the AsAi variant showed a trend, which was not statistically significant to an enhanced oncogenicity. European variants seemed to be significantly associated with a lower risk for cervical cancer development. The distribution of HPV 16 and 18 variants was not related to age or race among women living in the same geographical region. Knowledge of variants will be important for risk determination as well as for designing primers or probes for HPV detection methods, and for appropriate cervical cancer prevention strategies.     

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.     

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.     

Detection of human papillomavirus (HPV) type 16 and 52b in cervical cancer tissues by Southern blot hybridization and polymerase chain reaction (PCR)

DNA samples from cancer tissues diagnosed histologically as squamous cell carcinoma of the uterine cervix were examined for the presence of human papillomavirus (HPV) genome DNA by Southern blot hybridization. Of 63 specimens, 32 were found to hybridize with HPV DNA probes; 23 specimens (35%) with HPV type 16 (HPV16), one (2%) with HPV type 18 (HPV18), four (7%) with HPV type 52b (HPV52b), and four others (7%) weakly with HPV52b. Specimens negative for HPV DNA with Southern blot hybridization were subjected to polymerase chain reaction (PCR) to determine the presence of HPV DNA under more sensitive conditions. After PCR using one set of primers specific for HPV16 and HPV52b, 7 out of 31 specimens were found to have HPV16 DNA. None was positive for HPV52b DNA. Our results indicate that HPV52b, as well as HPV16 and HPV18, is associated with squamous cell carcinoma of uterine cervix, and more sensitive determination of HPV infection can be made by amplification of the viral genome by PCR.     

Prevalence of selective inhibition of HPV-16 DNA amplification in cervicovaginal lavages

HPV-16 viral load has been assessed with real-time PCR assays by measuring HPV-16 DNA and a human gene in genital samples. HPV-16 viral load measurements are thus based on the inference that inhibitors contained in samples will equally impede amplification of DNA sequences from HPV-16 and human DNA. We have previously shown that sample lysates can inhibit amplification of HPV-16 but not beta-globin DNA. In the current study, cervicovaginal lavages lysates considered adequate for PCR analysis by a qualitative beta-globin PCR test, were screened for the presence of inhibitors using internal controls (IC) for HPV-16 DNA and beta-globin in real-time PCR assays. Of 150 lysates screened with both ICs, 12 (8%) contained inhibitors. Inhibition of amplification of both ICs was demonstrated in four of these specimens. In eight lysates, amplification of HPV-16 IC only was impeded. Six (50%) of these 12 lysates tested positive for HPV-16 DNA despite the presence of PCR inhibitors. The HPV-16 viral load increased significantly after dilution of 11 of 12 lysates, demonstrating the presence of inhibitors in the undiluted lysate. Nine (90%) of 10 samples with inhibitors that were tested after dilution did not demonstrate inhibitory activity. The use of internal controls in real-time PCR is clearly essential to determine HPV viral loads since the effect of inhibitors on primer-driven genomic amplification is variable.     

Detection of specific types of human papillomavirus in cervical scrapes, anal scrapes, and anogenital biopsies by DNA hybridization

Specific varieties of human papillomavirus (HPV) infecting the anogenital region were detected in clinical samples by use of a filter hybridization technique suitable for rapid screening of cervical and anal scrapes. In this way possibly benign types (HPV6 and HPV11) could be differentiated from types thought to be capable of malignant transformation (HPV 16 and HPV 18). Cervical or anal canal cells were applied directly to nylon filters and fixed by u.v. irradiation before hybridization with mixed viral DNA probes under both low- and high-stringency conditions. In addition, probe for the human Alu-repeated DNA sequence was used to assess the relative amount of total nucleic acids in each sample applied to the filter. HPV DNA was detected in 3 of 19 cervical scrapes from patients with no past or present history of wart virus infection or cervical dysplasia. Within a positive study group totalling 71 patients, HPV (6/11 or 16/18) was detected in cervical scrapes from 24% of 41 patients who did not have visible genital dysplasia, 30% of 27 patients with visible genital dysplasia or cervical intraepithelial neoplasia (CIN) I, and in 1 of 3 patients with past CIN II/III. In addition, HPV6/11 or 16/18 DNA was detected in anal scrapes from 3 of 6 male patients and in 85% of genital biopsies. A notably high proportion (4/6) of vaginal condylomata were positive with both the HPV6/11 and the HPV16/18 mixed viral DNA probes. Of the biopsies prepared for histopathology and positive for HPV DNA, the HPV group-specific antigen could be detected in only 60%.     

Variation in human papillomavirus type-16 viral load within different histological grades of cervical neoplasia

The objective of this study was to investigate variation in human papillomavirus (HPV) type-16 load within histologically defined grades of cervical intraepithelial neoplasia. Two hundred and thirty-seven liquid based cytology samples were collected from women attending colposcopy clinics, DNA was extracted, and presence of virus determined by PCR-enzyme immunoassay. Quantitative real-time PCR was used to determine viral load for 70 HPV-16 positive single infections. Viral load was expressed as the ratio of copies of the viral L1 gene to copies of the human beta-globin gene. Measurements varied from 0.019 to 4,194 HPV genomes per cell. Our data demonstrate that in cervical neoplasia, HPV load tends to correlate with disease severity, but that the number of viral genomes/cell varies considerably within histological grades. This variation within disease grades currently limits the clinical utility of viral load measurement.     

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.     

Human papillomavirus integration: detection by in situ hybridization and potential clinical application

Human papillomaviruses (HPVs) are accepted as a necessary cause of cervical neoplasia. However, the benefits of testing simply for high-risk HPV types are limited because of their high prevalence in intraepithelial lesions of all grades, the majority of which regress if left untreated. One factor considered to be of key importance for the progression of intraepithelial lesions to invasive disease is integration of HPV into the host cell genome. Although questions remain about the prevalence of integration amongst pre-invasive lesions, sensitive in situ hybridization techniques utilizing tyramide reagents may aid determination of the significance of HPV infection by enabling routine detection of both high-risk HPV and its physical status. This will provide important data relevant not only to our understanding of the biology of HPV-associated neoplasia, but also potentially to clinical testing for HPV.     

Human papillomavirus is a necessary cause of invasive cervical cancer worldwide

A recent report that 93 per cent of invasive cervical cancers worldwide contain human papillomavirus (HPV) may be an underestimate, due to sample inadequacy or integration events affecting the HPV L1 gene, which is the target of the polymerase chain reaction (PCR)-based test which was used. The formerly HPV-negative cases from this study have therefore been reanalysed for HPV serum antibodies and HPV DNA. Serology for HPV 16 VLPs, E6, and E7 antibodies was performed on 49 of the 66 cases which were HPV-negative and a sample of 48 of the 866 cases which were HPV-positive in the original study. Moreover, 55 of the 66 formerly HPV-negative biopsies were also reanalysed by a sandwich procedure in which the outer sections in a series of sections are used for histological review, while the inner sections are assayed by three different HPV PCR assays targeting different open reading frames (ORFs). No significant difference was found in serology for HPV 16 proteins between the cases that were originally HPV PCR-negative and -positive. Type-specific E7 PCR for 14 high-risk HPV types detected HPV DNA in 38 (69 per cent) of the 55 originally HPV-negative and amplifiable specimens. The HPV types detected were 16, 18, 31, 33, 39, 45, 52, and 58. Two (4 per cent) additional cases were only HPV DNA-positive by E1 and/or L1 consensus PCR. Histological analysis of the 55 specimens revealed that 21 were qualitatively inadequate. Only two of the 34 adequate samples were HPV-negative on all PCR tests, as against 13 of the 21 that were inadequate ( p< 0·001). Combining the data from this and the previous study and excluding inadequate specimens, the worldwide HPV prevalence in cervical carcinomas is 99·7 per cent. The presence of HPV in virtually all cervical cancers implies the highest worldwide attributable fraction so far reported for a specific cause of any major human cancer. The extreme rarity of HPV-negative cancers reinforces the rationale for HPV testing in addition to, or even instead of, cervical cytology in routine cervical screening. Copyright © 1999 John Wiley & Sons, Ltd.     

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.     

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.     

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.     

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.     

Distribution of human papillomavirus among women with abnormal cervical cytology in Kuwait

This study investigates the distribution of human papillomavirus (HPV) in women with abnormal cervical cytology in Kuwait. Two hundred and ninety‐eight (298) abnormal ThinPreps were taken from women seeking routine gynecological care and screened for HPV DNA by real‐time PCR. HPV genotyping was determined by PCR‐based sequencing. HPV DNA was detected in 152 women (51%), and 29 different HPV genotypes were detected, comprising 16 high‐risk (HR) (16, 18, 31, 33, 35, 39, 45, 51, 53, 56, 58, 59, 66, 68, 73, 97), nine low‐risk (LR) (6, 11, 54, 61, 74, 81, 90, 102, 106), and four intermediate‐risk (IR) (62, 67, 84, 87). HPV16 had the highest prevalence (24.3%), followed by HPV11 (13.8%), HPV66 (11.2%), HPV33 (9.9%), HPV53 (9.2%), HPV81 (9.2%), HPV56 (7.9%) and HPV18 (6.6%). HPV prevalence was 86, 67, and 89% in women with invasive cervical carcinoma (ICC), high‐grade squamous intraepithelial lesion (HSIL) and low‐grade squamous intraepithelial lesion (LSIL), respectively. As for age distribution, 69% of all HPVs were found in women aged 20–29 years, and the HPV incidence rate deceased with increasing age. The proportion of single infections decreased as the severity of the cytological diagnosis increased, while the proportion of multiple infections increased. This study is the first of its type in Kuwait and one of few in the Middle East. The findings are consistent with the hypothesis that HPV infection is the primary cause of cervical neoplasia. They support HPV vaccine research to prevent cervical cancer and efforts to develop HPV DNA diagnostic tests. Diagn. Cytopathol. 2013. © 2011 Wiley Periodicals, Inc.