Prevalence and genotyping of high risk human papillomavirus in cervical cancer samples from Punjab, Pakistan

Detection of high-risk human papillomavirus infected cervical biopsies samples by immunohistochemical expression of the p16 tumor marker

Cervical cancer is the fourth most common type of cancer in women worldwide. It is widely accepted that the main cause of cervical cancer, especially in underdeveloped countries like Pakistan, is the infection caused by the human papillomavirus (HPV). The current screening and diagnostic methods face several challenges in accurately detecting the various types of lesions caused by HPV. Therefore, the present study was conducted to assess the effectiveness of p16 immunohistochemistry (IHC) analysis as a diagnostic method in samples of cervical biopsies. One hundred cervical biopsy samples were obtained from female patients across various age groups (> 20- ≤ 30, > 31- ≤ 40, > 41- ≤ 50, > 51- ≤ 60 years). These samples were subsequently prepared for subsequent examination. All samples were analyzed using automated tissue processing followed by Hematoxylin and Eosin (H & E) staining, and p16 IHC tumour marker staining. The H & E slides showed changes in normal cervical tissues, while four cervical abnormalities were identified statistically significant using p16 marker including chronic cervicitis, nabothian cyst formation, cervical intraepithelial neoplasia, and cervical cancers (P value 0.014). Furthermore, among females of different age groups (> 31- ≤ 40, > 41- ≤ 50, > 51- ≤ 60 years) were found statistically significant suffering from cervical cancer (P value 0.04), HPV with cervical cancer (P value 0.01), HPV with cervical intraepithelial neoplasia (P value 0.01). Based on the available data, it can be inferred that the incorporation of the p16 tumor marker may be a valuable method for detecting high-risk HPV in cervical biopsies samples.

Decoding the Genetic and Structural Features of HPV16 E5 Oncogene in Cervical Cancer Isolates from Pakistan: A Pilot Study

Background

Many anogenital cancers are caused by high-risk HPV. The most common subtype is HPV16, which is prevalent in the world, including Pakistan. Various amino acid residues in HPV16 E5 are associated with high cell cycle progression and proliferation. Lack of studies on HPV16E5 in Pakistan prompted the current study. This is the first report on the occurrence of pathogenic E5 variant of HPV16 in tissue sections obtained from invasive cervical cancerous patients in Pakistan.

Methods

A subset of 11 samples from HPV-positive biopsies were subjected to E5 gene amplification using PCR and analyzed using bioinformatics programs. The bioinformatics analysis detected mutations causing structural variations, which potentially contribute to the oncogenic properties of proteins.

Results

The two-point mutations, C3979A and G4042A, observed in isolate 11 caused the substitution of isoleucine for leucine and valine at positions 44 and 65 in E5 protein. The rest of the isolates had Leu44Val65 amino acids. Intratypic variations and phylogenetic analysis revealed that the majority of the isolates were closely clustered with European-Asian lineage. Moreover, C3979A and G4042A contributed to higher degree of interactions with host receptors, i.e. EGFR.

Conclusion

This is the first study reporting HPV16 variants in a Pakistani population based on variations in the E5 region. Our findings indicate that isolate 11 has a strong interaction with the intracellular domain of EGFR, which may enhance the generation of downstream signals. Since this was a pilot study to explore E5 gene mutation, future studies with large samples are absolutely needed.

Prevalence of HPV types in HIV-positive and negative females with normal cervical cytology or dysplasia

The burden of HPV varies by country and HIV status. The study aimed to evaluate HPV types prevalent in HIV-positive females compared with HIV-negative females in the local population of the federal capital territory in Pakistan.

METHOD

The selected female population consisted of 65 already diagnosed HIV-positive females and 135 HIV-negative females. Cervical scrap was collected and analyzed for HPV and cytology.

RESULTS

The prevalence of HPV in HIV-positive patients was 36.9%, higher than HIV-negative patients (4.4%). 12.30% had cervical cytology interpreted as "LSIL" and 87.69% had cytology interpreted as "NIL." The high-risk type was detected in 15.39% while 21.54% showed low-risk HPV types. Among the high-risk types, HPV18 (6.15%), HPV16 (4.62%), HPV45 (3.07%), HPV33 (1.53%), HPV58 (3.07%), and HPV68 (1.53%) were found. In patients with LSIL, high-risk HPV accounts for 62.5%. Risk factors, such as age, marital status, educational status, residence, parity, other STDs, and contraceptives, were analyzed to find the correlation with HPV infection Age ≤35 years (OR 1.21, 95% CI, 0.44-3.34), illiterate and incomplete secondary education (OR 1.08, 95% CI, 0.37-3.15), and those reported not to use contraceptives (OR: 1.90; 95% CI: 0.67-5.42) have an association for increased risk of HPV infection.

CONCLUSION

HPV18, HPV16, HPV58, HPV45, HPV68, and HPV33 were identified among high-risk HPV types. High-risk HPV was detected in 62.5% of low-grade squamous intraepithelial lesions. The data is useful for health policymakers to develop a strategy for HPV screening and prophylactic vaccination to prevent cervical cancer.

Genotypic distribution of human papillomavirus and phylogenetic analysis of E6 and E7 gene of HR-HPV variants isolated from Pakistani population

High-risk-human papillomavirus (HR-HPV)-induced cervical cancer is the second most common cause of death among females worldwide. HPV16 is the most prevalent HR-HPV infection worldwide. This study found the genotypic distribution of HR-HPV in the local population and investigated the sequence variations among the E6 and E7 oncogenes of the local HPV16 genotype to the E6 and E7 oncogenes of the foreign HPV16 genotypes and constructed a phylogenetic relationship based on nucleotide sequence comparison among the variants identified in our study along with previously reported isolates that were obtained from different regions of the world. The samples were collected from patients with cervical cancer. Genomic DNA was extracted, and HR-HPV genotypes were determined using real-time PCR. The HPV16 E6 and E7 genes were amplified and sequenced. A HPV16 phylogenetic tree was constructed using the maximum likelihood method with MEGA 7. HPV16 was the most prevalent human papillomavirus (HPV) type identified in the present study. HPV16 isolates belonged to the A1 sublineage of the European branch. Twenty-one nucleotide sequences were included in this analysis. The first, second, and third codon positions are also included. The final dataset included 776 positions.

Prevalence and Current Scenario of HPV in Pakistan: A Systematic Review and Meta-analysis

AIM: The present study was designed to compile and screen data regarding HPV-related reported diseases to evaluate the status of HPV infection in Pakistan. METHODS: The literature on the prevalence of HPV in Pakistan was searched in Google Scholar and other search engines using various keywords. RESULTS: A total of 39 studies published from 2007 to 2018 were reviewed. About 7341 participants have been screened for HPV in Pakistan for the past 11 years, and according to this meta-analysis, the reported HPV prevalence was 23.1%. The highest HPV prevalence rate was observed among cervical cancer cases (80.4%) followed by normal cervical region (61.8%) and oral cancer (40.4%), respectively. CONCLUSION: The high prevalence of HPV in Pakistan reflects the raised burden of HPV-associated diseases. The health-care system needs to be more organized in terms of awareness and screening programs, diagnosis, and treatment of the disease to reduce the burden of HPV in Pakistan.

Prevalence and Type Distribution of Human Papillomavirus Recovered from the Uterine Cervix of Nigerian Women: A Systematic Review and Meta-Analysis

Background: Infection with an oncogenic type of human papillomavirus is a prerequisite for the development of precancerous cervical lesions and its subsequent progression to cervical cancer. With an alarming increase in the detection of other suspicious papillomavirus genotypes in both healthy and women with cervical lesions, there is a need for comprehensive data on cervical papillomavirus infection to address cervical cancer and other associated disease burden, especially in Sub-Sarahan Africa, where the bulk of the problem exists. The present study was conducted to develop comprehensive data on the prevalence and circulating genotypes of human papillomavirus in various risk categories in Nigeria. Methods: A systematic review and meta-analysis of peer-reviewed publications on cervical papillomavirus infection were performed. Relevant data were extracted from eligible studies published in PubMed, Web of Science, Embase, Scopus, and Google Scholar, from inception to July 31, 2019. The random-effect model was used to estimate the pooled prevalence. We identified 327 potential studies and pooled data from 18 studies, involving 5697 women aged 15-86 years. Results: The overall pooled prevalence of cervical papillomavirus infection was 42% (95%CI: 30-54%) in the general population and 37% (95%CI: 25-50%) among women living with HIV/AIDS, with the predominance of genotypes 16, 18, 31, 35, 52, 58 and 45. The highest prevalence was observed in teenagers and young adults and the second peak in women 50 years and above. Conclusion: The prevalence of cervical human papillomavirus infection is cumulatively high in Nigeria and HIV is a strong co-factor. We, therefore, strongly recommend the co-screening of human papillomavirus and cervical cancer and integration of the intervention strategy into the existing HIV-care guideline in Nigeria.

A Meta-Analysis on Human Papillomavirus Type Distribution among Women with Cervical Neoplasia in the WHO Eastern Mediterranean Region

INTRODUCTION

To date, the human papillomavirus (HPV) vaccine has not been integrated into the national vaccination program of most countries of the WHO Eastern Mediterranean Region (EMRO), except for the United Arab Emirates and Libya. The knowledge of HPV genotype distribution in cervical neoplasia is valuable to predict the impact of current HPV vaccines on cancer prevention and can help the health policymakers to select the most appropriate vaccine types in their countries.

METHODS

Hence, this meta-analysis recapitulates all available data on HPV prevalence and genotypes in women with atypical squamous cells of undetermined significance (ASCUS), cervical intraepithelial neoplasia (CIN) I-III or low- and high-grade squamous intraepithelial lesions (LSIL and HSIL, respectively), and invasive cervical cancer (ICC) in EMRO countries.

RESULTS

The meta-analysis included 5,990 cases of cervical precancer and cancer. The overall HPV prevalence was 85.4, 71.3, 59.2, and 34.8% in women with ICC, CIN II-III or HSIL, CIN I or LSIL, and ASCUS, respectively. HPV 16 was the most common genotype followed by HPV 18, representing 58 and 16.5% in ICC cases, respectively.

CONCLUSION

This meta-analysis showed that the introduction of current HPV vaccines into national vaccination programs and the establishment of comprehensive screening programs in EMRO countries is beneficial by preventing 74.5% of cervical neoplasia.

The Situation of Cervical Cancers in the Context of Female Genital Cancer Clustering and Burden of Disease in Arad County, Romania

Romania has the highest incidence of cervical cancer morbidity and mortality in Europe. This study identifies the major clusters for genital cancers, observes the features of genital and cervical cancer, and determines the extent to which cancer is a contributor to total Disability-Adjusted Life Year (DALY). Spatial analysis used Besag and Newell’s method for genital cancer distribution, prevalence considered Arad County patients records (2008–2017), and DALY was determined according to WHO methodology and GLOBOCAN 2013 data. Diagnosis was established by histopathological examination of diagnostic biopsies or tissues obtained by surgical procedures, followed by clinical staging. 1695 women were recorded with genital cancer. Of these, 14.9% of lesions were in situ (n = 252) and 74.20% of cases were recorded in stage III or IV (n = 1258) (p < 0.0001). Over 90% of cervical cancers were squamous cell carcinomas (n = 728), 33.76% of endometrial cancers were adenocarcinomas in situ (n = 131), 32.42% of ovarian cancers were serous adenocarcinomas (n = 131), and 70.58% of vulvar cancers were squamous cell carcinomas (n = 48) (p < 0.0001). DALY/1000 was 67.2 for genital cancers and 33 for cervical cancers. From the point of view of Romanian women, cervical cancer remains one of the major problems that need to be dealt with and access to optimal treatment proves to be extremely limited.

The development of simultaneous measurement of viral load and physical status for human papillomavirus 16 and 18 co-infection using multiplex quantitative polymerase chain reaction

Persistent infection with human papillomavirus (HPV) type 16 and 18 is known to be a major risk factor for cervical cancer. Increased prevalence of co-infection with these high-risk types has been observed in pre-cancerous and cancerous tissues. The determination of physical status and copy numbers of viruses is therefore useful in clinical settings. A simple multiplex quantitative polymerase chain reaction (qPCR) for HPV16/HPV18 co-infection in one tube reaction was established in the present study using TaqMan^®-based PCR for E2 and E6 viral DNA. The detection range was up to 10⁶ copies with 100% specificity and high precision (CV of cycle time <0.5%). The analytical accuracy and robustness were verified by competitive assay using an unequal mixture of HPV16/HPV18 DNA. No significant effect was demonstrated when compared with the simplex qPCR. The detection of physical status was evaluated in cervical samples, including 5 pre-cancerous and 15 cancerous samples. No significant difference was observed between simplex and multiplex qPCR (P=0.372). In conclusion, the developed multiplex qPCR method successfully demonstrated the viral status of the common HPV types in one tube. This assay will facilitate viral assessment and monitoring of cervical cancer associated with HPV16 and HPV18 co-infection.

A high prevalence of human papillomavirus 16 and 18 co-infections in cervical biopsies from southern Brazil

HPV types 16 and 18 were studied in paraffin-fixed cervical biopsy collected in southern Brazil. HPV 16, HPV 18 and co-infection HPV 16/18 were identified in 10/57 (17.5%), 4/57 (7%) and in 43/57 (75.4%) samples, respectively. Southern Brazil has one of the highest prevalence rates of HPV 16/18 reported.

Prevalence and age-wise distribution of Human Papillomavirus type 16/18 infections among hospital screened women of a peri-urban area in West Bengal: Impact of socio-demographic factors

BACKGROUND

We undertook the current study on cervical Human Papillomavirus (HPV) prevalence along with cytology in women visiting the Gynecology Out-patient Department of a hospital for common gynecological ailments, subsequent to our earlier population-based study on HPV prevalence from India.

METHODS

We analyzed data on cervical-cytology (Pap smears) and PCR-based molecular detection of HPV infection along with socio-demographic variables (N = 696).

RESULTS

We identified 36.84% HPV-positive women amongst whom, HPV16 and 18 together predominated (79.37%) over other HPV types (20.63%). Contrarily, only 6.4% women revealed abnormal cytological lesions, of which, 46.51% were HPV-positive and 95% of such women harbored HPV16/18, while 5% harbored other HPV types. Individuals with normal cytology portrayed 36.09% HPV infections, of which, 77.97% were HPV16/18-positive and 22.03% harbored other HPV types. Overall HPV prevalence decreased significantly (p_trend  = 0.047) with increase in age, but HPV16/18 infections were significantly over-represented compared to the other HPV types across all age-groups. Specifically, HPV16 prevalence increased (p _trend < 0.01) with increase in severity of cervical lesions. HPV16 prevalence did not differ between the Hindus and Muslims but HPV18 was significantly higher among the cytologically normal Muslim women (24.14%, p = 0.02), compared to the Hindus (11.91%), specifically among those ≥ 30 years of age. There was a significant (p < 0.05) overrepresentation of HPV16 prevalence among women who were users of oral contraceptive-pills, irrespective of cytology.

CONCLUSIONS

Our study highlights the need for HPV16/18-based screening of cervical cancers in India considering the immense socio-cultural and genetic diversity at the population level.

Epidemiological study of high-risk human papillomavirus infection in subjects with abnormal cytological findings in cervical cancer screening

The present study aimed to determine the genotype and age distribution of high-risk human papillomavirus (HR-HPV) and evaluate HPV-DNA in subjects with abnormal cervical cytology results by using crowd-based cervical cancer screening cytology data. The Thinprep liquid-based cytologic test (TCT) was performed from January 2013 to January 2014 in the permanent residents of Liaocheng (China) aged 21-65 years who were married or had sexual intercourse. The number of screened women totaled 20,017, among whom 937 had abnormal results, 785 of which were recalled. For subjects in the age range of 21-65 years, an HR-HPV typing test using the fluorescence hybridization method. Among the 785 cases with abnormal TCT findings, repeated testing identified atypical squamous cells of unknown significance/atypical glandular cells in 478, low-grade squamous intraepithelial lesions in 175, high squamous intraepithelial lesions in 127 and squamous cell carcinoma/adenocarcinoma in 5 cases. Among these types, infection rates of HR-HPV were 50.2, 77.1, 89.0 and 100%, respectively. Of the 785 cases with abnormal TCT results, 493 (62.8%) were HR-HPV-positive. A total of 16 types of HR-HPV were detected: HPV-16, -18, -31, -33, -35, -39, -45, -51-53, -56, -58, -59, -66, 68 and 73. Subjects infected with ≥2 types were defined as having a multi-type infection. The infection rate was high in the age groups of 26-30 and 51-55 years, accounting for 87.7% (71/81) and 79.7% (51/64), respectively, while it was lower in the >55 years group at 28.6% (14/54). The top five types of HR-HPV (stated in a decreasing order regarding positivity rate) were HPV16 (21.5%, 169/785), HPV52 (12.2%, 96/785), HPV58 (9.8%, 77/785), HPV33 (9.7%, 76/785) and HPV18 (7.5%, 59/785). Single-type infection was encountered in 45.0% (353/785) and multi-type infection in 17.8% (140/785), among which 98 cases had a two-type infection, 37 had a three-type infection, 2 had a four-type infection, 2 had a five-type infection and 1 case had a six-type infection. In the present study, differences in multi-type HR-HPV infection between groups with different TCT results were statistically significant. In conclusion, compared with CTC screening on its own, complementary HR-HPV testing is an effective method for screening for cervical cancer. The infection rate of HPV16, -52, -58, -33 and -18 was high among patients with cervical cytological abnormalities. Multi-type infection adds to the risk of malignancies. In Liaocheng, high-risk groups were aged 26-30 and 51-55. Attention should be paid during the screening and follow-up visits of these groups.

Prevalence of Human Papillomavirus subtypes 16 and 18 among Yemeni Patients with Cervical Cancer

Background: The Human Papillomavirus (HPV) is a DNA tumor virus that causes epithelial proliferation. There are more than 100 HPV subtypes, of which 13 subtypes are regarded as high risk subtypes that can cause cancers of epithelial mucosal surfaces. High risk human papilloma viruses (HR-HPV) subtypes 16 and 18 plays a major role in the etiology of cervical cancer worldwide. Therefore, the aim of this study was to screen for the existence of HPV16 and HPV18 among Yemeni women with cervical lesions. Methodology: Formalin fixed paraffin wax processed tissue blocks were retrieved for 200 patients (150 were previously diagnosed with cervical cancer and the remaining 50 were diagnosed with different benign conditions). Results: Of the 200 cervical cancer tissue specimens, HR-HPV 16 was identified in 74/200 (37%) samples and couldn’t be recognized in 126/200(63%) tissue samples. HR-HPV 18 was identified in 32/200 (16%) specimens and couldn’t be recognized in 168/200(84%) tissue specimens. Conclusion: HR-HPV subtypes were prevalent among Yemeni women with cervical cancer, with significant increase of HR-HPV subtype 16 over the HR-HPV subtype 18.

Cervical Cancer and Genital Infections: Assessment of Performance and Validation in Human Papillomavirus Genotyping Assays in Iran, its Neighbouring Countries and Persian Gulf Area

BACKGROUND

The accuracy of diagnostic assays in Human Papillomavirus (HPV) genital infection and cervical cancer has remained a clinical challenge in diagnosis. Evidence indicates that a large proportion of cervical cancer can be prevented through organized care for HPV and testing. Countries with low per capita income, such as Iran and its neighbours, have no national organized program for cervical cancer screening and vaccination. The aim of this study was to review recent published papers in this region for evaluating the efficacy of released data regarding HPV genotyping system in genital infections and cervical cancer.

METHODS

Investigating various medical search engines retrieved 46 reports, mostly after 2010, consisting of either home brew protocols or commercial technologies in this field.

RESULTS

Summarized results demonstrated that except a few cases, all reports were limited studies performed in confined populations focusing on attending patients at clinics for regular checkups. In the present study, 52.8% of papers were from Iran and the rest belonged to other countries. The rate of HPV infection was reported in the range of 0.62% to 25% in the normal population, while it varied from 18.75% to 100% in females with cervical cancer. In HPV genotyping surveys, only 26.1 % (12/46) of reports had validated and World Health Organization (WHO) proficient procedures. Also, multiple infections were not mentioned in 56.52% (25/46) of researches.

CONCLUSIONS

Employing reliable genotyping methods is the best way for regular screening of cervical cancer related to HPV and precancerous diseases in females of these areas. The focus of most surveys was to come up with the best national policies for establishing a preventive program in Iran and Persian Gulf area.

HPV Genotypes distribution in Indian women with and without cervical carcinoma: Implication for HPV vaccination program in Odisha, Eastern India

BACKGROUND

Considering the limited cross protection offered by the current HPV vaccines, understanding the HPV genotype distribution among the different population is essential in predicting the efficacy of current vaccine and devising new vaccine strategy. The present work aimed at investigating the HPV genotypes distribution among women with and without cervical carcinoma in Odisha, Eastern India.

METHODS

A total of 607 participants have been enrolled between January 2014 and June 2016. L1-PCR, sequencing, and E6/E7 nested multiplex type- specific PCR were performed for HPV detection and genotyping. Cytological distribution of 440 cases includes invasive cervical carcinoma or ICC (n = 210), inflammatory smear (n = 162), normal cytology (n = 68). Statistical analyses were performed by using SPSS version 20.0 software and MediCal version 14.10.2(7). A p-value of ≤ 0.05 was considered statistically significant.

RESULTS

The overall prevalence of HPV infection was (359/595) 60.33%. Prevalence of HPV infection was 93.80% (197/210) in invasive cervical cancer (ICC) cases, 54.32% (88/162) in inflammatory smear and 19.11% (13/68) in normal cervical cytology. The most prevalent genotype was HPV16 (87.28%) followed by HPV18 (24.56%) and HPV 51(3.46%). The overall prevalence of single type was 76.58% and highest (78.9%) among ICC cases. The most frequent genotype combination after HPV16 + 18(9.4%) was HPV16 + 66 + 68(2.7%) which was frequently observed in inflammatory cytology. Age > 45years, parity ≥3, low socio-economic condition, rural residential area and post menopause state were significantly associated with HPV infection. Multiple infections did not have a significant association with any of the clinicopathological variables (stage, LN metastasis, cell type) except tumor size ≥ 2cm in ICC cases. The impact of 2v, 4v, and 9v vaccines in preventing cervical cancer in Odisha were 89.99, 91.65, and 92.16% respectively.

CONCLUSION

This data would help planning an appropriate strategy for disease monitoring and provides baseline data for post-vaccination surveillance in the region. The nonavalent vaccine would be significant in preventing cervical carcinoma in Odisha. Hence an effective vaccination program based on regional HPV epidemiological profile along with the cervical cancer screening is necessary to reduce the cervical cancer burden in India.

Retrospective analysis of HPV 16/18-related disease burden using archival clinical samples

PURPOSE

Estimation of HPV-related disease burden lies at the core of effective disease management. HPV testing is heavily reliant on its retrospective detection in archival clinical cancer samples, especially in parts of the world where HPV screening is not routinely practiced. During the last decade, valuable insights were gained through regional reports based on occasional screening of cervical smears or biopsy sections for the presence of high-risk HPV. HPV 16 and 18 were found to be predominant high-risk HPV subtypes with some regional differences and incidences of co-infections, detected mostly through PCR-based methods. In cases of multiple infections, the presence of viral DNA may not signify its etiologic involvement. The current study, therefore, combines PCR-based detection method with the immunohistochemical (IHC) detection of early viral protein E6 expression, in order to obtain a reliable read out for the disease causing viral subtype, especially in cases of co-infections with oncogenic subtypes other than HPV 16 and 18. Immunohistochemistry (IHC) and PCR-based methods are routinely used laboratory techniques in local hospitals. The concordance between IHC and PCR-based analyses may be useful for determining effective method for the retrospective testing of HPV 16 and 18 disease-related burden.

METHODS

A total of 49 paraffin-embedded cervical cancer biopsy sections representing patients from the northwest region of the country were collected from the tertiary care hospital for this study. Genotyping for HPV 16 and 18 was carried out through PCR. The HPV 16/18 E6 protein expression was evaluated by IHC and was compared with the clinicopathological features of cervical cancer.

RESULTS

Molecular analysis of 33 (67 %), E6-expressing paraffin-embedded cervical cancer biopsy sections revealed the presence of HPV 16 (n = 23; 47 %), HPV 18 (n = 6; 12 %) and co-infection (n = 4; 8 %) in 49 tumors through PCR. Despite the PCR-based detection of viral DNA in 37 cervical cancer samples, IHC analysis of E6 expression revealed the etiological involvement of HPV 16/18 in 33 out of 37 cervical cancer samples. Overall, there was 85 % concordance in the results of the two techniques.

CONCLUSION

IHC analysis provides more conclusive evidence regarding the etiological involvement of the viral subtypes, especially in the presence of multiple infections. About two-thirds (67 %) of cervical cancer samples were found to be caused due to HPV 16/18. Latent occurrence of HPV 16 and 18 is suggested in less than 10 % cervical cancer samples which were found to harbor viral DNA without E6 expression. Furthermore, E6 expression was found to be significantly correlated with the tumor grade.

Human Papillomavirus Genotype Distribution in Invasive Cervical Cancer in Pakistan

Few studies have assessed the burden of human papillomavirus (HPV) infection in Pakistan. We aim to provide specific information on HPV-type distribution in invasive cervical cancer (ICC) in the country. A total of 280 formalin-fixed paraffin-embedded tissue blocks were consecutively selected from Shaukat Khanum Memorial Cancer Hospital and Research Centre (Lahore, Pakistan). HPV-DNA was detected by SPF10 broad-spectrum PCR followed by DNA enzyme immunoassay and genotyping by LiPA25. HPV-DNA prevalence was 87.5% (95%CI: 83.0–91.1), with 96.1% of cases histologically classified as squamous cell carcinoma. Most of the HPV-DNA positive cases presented single infections (95.9%). HPV16 was the most common type followed by HPV18 and 45. Among HPV-DNA positive, a significantly higher contribution of HPV16/18 was detected in Pakistan (78.4%; 72.7–83.3), compared to Asia (71.6%; 69.9–73.4) and worldwide (70.8%; 69.9–71.8) and a lower contribution of HPVs31/33/45/52/58 (11.1%; 7.9–15.7 vs. 19.8%; 18.3–21.3 and 18.5%; 17.7–19.3). HPV18 or HPV45 positive ICC cases were significantly younger than cases infected by HPV16 (mean age: 43.3, 44.4, 50.5 years, respectively). A routine cervical cancer screening and HPV vaccination program does not yet exist in Pakistan; however, the country could benefit from national integrated efforts for cervical cancer prevention and control. Calculated estimations based on our results show that current HPV vaccine could potentially prevent new ICC cases.

Molecular Epidemiology of High-Risk Human Papillomavirus in High-Grade Cervical Intraepithelial Neoplasia and in Cervical Cancer in Parakou, Republic of Benin

Human papilloma virus (HPV) infection remains a worldwide concern, especially in Sub-Saharan Africa where cervical cancer is the leading cause of cancer death in women. The aim of the study was to determine the prevalence and genotypic distribution of High-Risk HPV (HR-HPV) involved in Cervical Intraepithelial Neoplasia (CIN) II and III and in cervical cancer in Parakou. Out of a total of 149 samples of cervical tissues archived, fixed and paraffin-embedded, 78 samples with histological diagnosis of CIN-II, CIN-III and cervical cancer went through deparaffinization with xylene, followed by an extraction of HPV DNA and the detection of HR-HPV by real-time multiplex PCR. The average age of the women was 40.05±13.99 years. The samples were positive to at least one HR-HPV genotype in 76.92% (50/65) of cases. The HR-HPV genotypes which are most common in the cervical cancer and in CIN-II and III were, respectively HPV-39 (38 and 37.50%), HPV-18 (35 and 31.30%), HPV-45 (35 and 31.30%), HPV-35 (9 and 25%) and HPV-52 (9 and 12.50%). The HPV-16 was absent. This study helped to detect (in samples archived, fixed and paraffin-embedded tissues) HR-HPV involved in high-grade precancerous lesions and in cervical cancer in Parakou, some of which are not covered by currently available vaccines.

Genetic variation of high-risk HPV-16 from a cervical cancer biopsy collected in Pakistan

Aim: HPV-16 is one of the causative agents of cervical cancer. The HPV-16 genome is characterized widely to assist mutagenesis studies, phylogenetic analysis and protein annotations. This is the first report of HPV-16 sequence analysis from Pakistan. Materials & methods: The gene and long control region specific primers were used to generate the targeted amplicons that were then cloned and sequenced. Results: The complete genome analysis revealed nine changes both at amino acid and nucleotide level including seven novel and two previously reported mutations. The evolutionary relationship of HPV from Pakistan and reported sequences shows that strain reported in this study segregates with European taxa. Conclusion: This report lays foundation to conduct HPV genome mutation analysis in Pakistan.

Frequency of Human Papilloma Virus (HPV) subtypes 31,33,35,39 and 45 among Yemeni women with cervical cancer

Background

Identification of different HPV subtypes in unidentified communities provides sufficient information for screening and monitoring potential impact of a vaccination program. Therefore, the aim of this study was to screen for the presence of HPVs subtypes 31,33,35,39 and 45 among Yemeni women with Cervical Cancer.

Methodology

A total of 200 (150 malignant and 50 benign) tissue samples were obtained from Yemeni women with cervical cancer, were investigated for the presence of HPV subtypes 31,33,35,39 and 45 by Polymerase Chain Reaction (PCR).

Results

Of the 150 cervical cancer tissue specimens, HPV 31, HPV 33, HPV35, HPV 39 and HPV45 were identified in 10/150 (6.7 %), 6/150 (4 %), 6/150 (4 %), 5/150 (3.3 %) and 10/150 (6.7 %), respectively. The frequency of these HPV subtypes among Yemeni women with cervical cancer was 24 %. Conclusion: HPV 31, HPV 33, HPV35, HPV 39 and HPV45 were prevalent among Yemeni women with cervical cancer.

Prevalence of High risk Human Papillomavirus in cervical dysplasia and cancer samples from twin cities in Pakistan

INTRODUCTION

Human Papilloma Virus (HPV) is small DNA virus mostly infecting mucosa and cutaneous keratinocytes. So far, more than 200 Human papillomaviruses are known. HPV have been divided into high- and low-risk on the basis of their oncogenic potential. High risk HPV is considered to be the main etiological cause for cervical cancer.

OBJECTIVE

The current study was designed to screen the local cervical cancer patients from the twin cities of Pakistan for the occurance of high risk HPV.

METHODOLOGY

A total of 67 formalin fixed paraffin-embedded samples of cervical cancer biopsies were obtained from the government hospitals in Islamabad and Rawalpindi. Cervical cancer biopsies were examined for the presence of HPV DNA. Polymerase chain reaction (PCR) was used for the amplification of a region in the HPV-L1 gene for the general detection of the Papilloma virus and for the genotype specific detection of high risk HPV 16 and 18 using the GP5/GP6 primers and genotype specific primers, respectively.

RESULTS

HPV DNA was detected in 59 out of 67 samples analyzed. 30 samples showed the presence of HPV16 while 22 samples were positive for HPV18. HPV subtype could not be determined in 7 samples.

CONCLUSION

Our results show a strong association between HPV infection and cervical cancer among women in twin cities of Pakistan. One way to minimize the disease burden in relation to HPV infection in Pakistani population is the use of prophylactic vaccines and routine screening. An early diagnosis of HPV infection will allow better health management to reduce the risk of developing cervical cancer.