Prospects and prejudices of human papillomavirus vaccines in India

Human papillomavirus screening in north Indian women

OBJECTIVES

Human papillomavirus (HPV) is the major etiological agent of cervical cancer, a leading cause of morbidity and mortality in women worldwide. Screening strategies for reducing the burden of HPV-mediated carcinogenesis are emerging as an effective means for cervical cancer control and prevention in developing countries. Our study, therefore, aimed to identify HPV infection status in North Indian women during random population screening.

METHODOLOGY

Cervical/vaginal exfoliated cells and/or Pap smear specimens were collected from 890 women of North Indian ethnicity residing in Lucknow and adjoining areas, during random population screening from June 2009-March 2012. HPV viral loads in clinical specimens were determined by the Hybrid Capture (hc)-2 HPV DNA assay, and subsequently, positive/negative/borderline HPV status was calculated.

RESULTS

The HPV incidence in the present study was 11.7%. 751 out of a total of 890 women (84.4%) participating in our HPV screening program were HPV negative (HPV -), 104 (11.7%) tested positive (HPV +) while 35 (3.9%) showed borderline (HPV *) infection status. Furthermore, in the HPV + subjects (N=104), 18 (17.3%) showed strong positivity. We observed that HPV positivity tends to increase with age in North Indian women; the higher the viral load with increasing age, higher is the susceptibility to HPV-mediated cervical cancer.

CONCLUSIONS

HPV viral load/genotyping may help in identifying women at risk of developing cervical cancer. However, cost- effective HPV screening protocols with a wider population coverage are warranted so as to reduce the burden of cervical cancer in women worldwide in the vaccine-era.

Downregulation of tumor suppressor gene PML in uterine cervical carcinogenesis: impact of human papillomavirus infection (HPV)

OBJECTIVES

Cervical cancer is a leading gynecological cancer in Indian women and is caused due to infection with high risk human pappilloma virus (HR-HPV) 16 and 18. It has been well documented that PML (promyelocytic leukemia) enhances viral infectivity and plays a crucial role in antiviral response mechanisms. The aim of the present study was to evaluate the role of PML gene with context to HPV infection in cervical carcinogenesis.

METHODS

The expression pattern of PML was analyzed by western blotting and immunohistochemistry in a total of 170 fresh surgically resected cervical tissue specimens comprising precancer (n=12), cancer (n=118) and normal controls (n=40) recruited from PGIMER, Chandigarh, India. HPV status was analyzed by L1 consensus PCR followed by type specific PCR for HR-HPV types 16 and 18 and low risk types 6 and 11.

RESULTS

A significant downregulation of PML protein was observed in the majority of cervical cancer and precancer cases 68% (89/130) compared to normal controls. The loss of expression pattern of PML gene was significantly increased with severity of disease both clinically and pathologically (p<0.001). HPV infection was detected in the majority of cancer cases 96% (113/118) and in 83% (10/12) of precancer lesions whereas no infection could be detected in normal controls. Interestingly, all the 68% (89/130) cervical cancer cases that showed downregulation of PML were HPV infected (p=0.0001).

CONCLUSION

Taken together, these observations suggest that the downregulation of PML gene and its synergism with HPV infection may play an important role and may serve as a new marker for early diagnosis and therapeutic intervention for cervical carcinogenesis.

Human papillomavirus infection among young adolescents in India: impact of vaccination

High-risk human papillomaviruses (HR-HPVs) are the causative agents of cervical cancer and prophylactic HPV vaccination has been recommended for adolescents but no data are available on the prevalence of HPV infection among adolescents in India. Self-collected midstream urine samples from 940 healthy school children, aged 8-17 years, from 12 different schools in and around Noida and Delhi, India, were collected for HPV detection by PCR. Of 458 girls, 15 (3.2%) were positive for HPV and 10 (66.6%) were positive for high-risk human papillomavirus (HR-HPV) type16 and 2 (13.3%) for HPV 18. Of 342 boys, 7 (2.1%) were HPV positive, of which 5 (71.4%) had HPV type 6 but interestingly, none were positive for HR-HPV types 16 or 18. Among HPV positive girls, 13 (66.6%) were >13 years and the rest were <13 years (P = 0.004), while all seven HPV positive boys were >13 years (P = 0.007). The majority of HPV positive adolescents (80-86%) belonged to the Hindu and related communities, whereas only about 14-20% belonged to the Muslim community. A significant association (P < 0.001) was observed between the parent's education and the awareness of cervical cancer, which was significantly higher among adolescent girls from India, thereby exerting an immense psychosocial impact on vaccination programs. A lower prevalence of HR-HPV infection among adolescent girls will have significant positive effect on HPV vaccination and cancer control programs in India where education and awareness should go hand in hand.

Safety and immunogenicity profile of human papillomavirus-16/18 AS04 adjuvant cervical cancer vaccine: a randomized controlled trial in healthy adolescent girls of Bangladesh

Aim

Bangladesh has the highest level of incidence and mortality rates due to cervical cancer among women. The prevalence of cervical cancer in Bangladeshi women is 25–30/100 000. Human papillomavirus is an important cause of cervical cancer. The study was conducted to assess the immunogenicity and safety profile of human papillomavirus-16/18 AS04-adjuvanted cervical cancer vaccines in healthy Bangladeshi girls aged 9–13 years.

Procedure

This was a randomized (3:1) controlled trial with two parallel groups, the vaccine and control groups, that included 67 participants in Bangladesh. Subjects were given GlaxoSmithKline human papillomavirus-16/18 AS04-adjuvanted cervical cancer vaccine (and controls no vaccine) at the first day of vaccination (Day 0), at 1- and 6-month schedule and followed up until 7 months. Blood samples were taken for human papillomavirus antibody at enrollment and 1 month post-schedule at Month 7 from both subjects and controls. Safety data were gathered throughout the study period.

Results

Fifty subjects received vaccine at Day 0, 1 month and 6 months. All subjects were initially sero-negative in the vaccine group, and developed sero-conversion for human papillomavirus-16 and -18 antibodies except for one at Month 7. Seventeen controls did not receive vaccine. Clients were followed up for serious medically important events and blood samples were taken for human papillomavirus antibody detection at Day 0 and Month 7. Sero-conversion was found in 97.5% of subjects and no sero-conversion was found in the controls. Bivalent human papillomavirus vaccine was generally well tolerated, with no vaccine-related serious adverse experiences.

Conclusions

The human papillomavirus-16/18 AS04-adjuvanted vaccine was generally well tolerated and highly immunogenic when administered to young adolescent females and could be a promising tool for the prevention and control of cervical cancer in Bangladesh.

Human papillomavirus vaccine delivery strategies that achieved high coverage in low- and middle-income countries

OBJECTIVE

To assess human papillomavirus (HPV) vaccination coverage after demonstration projects conducted in India, Peru, Uganda and Viet Nam by PATH and national governments and to explore the reasons for vaccine acceptance or refusal.

METHODS

Vaccines were delivered through schools or health centres or in combination with other health interventions, and either monthly or through campaigns at fixed time points. Using a two-stage cluster sample design, the authors selected households in demonstration project areas and interviewed over 7000 parents or guardians of adolescent girls to assess coverage and acceptability. They defined full vaccination as the receipt of all three vaccine doses and used an open-ended question to explore acceptability.

FINDINGS

Vaccination coverage in school-based programmes was 82.6% (95% confidence interval, CI: 79.3-85.6) in Peru, 88.9% (95% CI: 84.7-92.4) in 2009 in Uganda and 96.1% (95% CI: 93.0-97.8) in 2009 in Viet Nam. In India, a campaign approach achieved 77.2% (95% CI: 72.4-81.6) to 87.8% (95% CI: 84.3-91.3) coverage, whereas monthly delivery achieved 68.4% (95% CI: 63.4-73.4) to 83.3% (95% CI: 79.3-87.3) coverage. More than two thirds of respondents gave as reasons for accepting the HPV vaccine that: (i) it protects against cervical cancer; (ii) it prevents disease, or (iii) vaccines are good. Refusal was more often driven by programmatic considerations (e.g. school absenteeism) than by opposition to the vaccine.

CONCLUSION

High coverage with HPV vaccine among young adolescent girls was achieved through various delivery strategies in the developing countries studied. Reinforcing positive motivators for vaccine acceptance is likely to facilitate uptake.

Implementing HPV Vaccines: Public Knowledge, Attitudes, and the Need for Education

This article reviews qualitative research on public knowledge and attitudes to HPV vaccines, focusing on socio-economically challenged populations. Keyword searches were conducted on MEDLINE and ISI Web of Science for relevant peer-reviewed literature in English. A high acceptance of HPV vaccines was found despite low knowledge about HPV (types, prevalence, transmission, health risks, and cervical screening). Facilitators of HPV vaccine uptake included fear of cancer and desire to protect children's health. Barriers included low knowledge levels, perception of HPV vaccines as potential causes of sexual disinhibition, concerns about vaccine costs, social stigma, adverse effects, and parental unwillingness to permit vaccination of pre-adolescent children. Despite acceptance of HPV vaccines, implementation in low-resource settings faces social and economic difficulties. To pursue and strengthen cervical screening in these settings, public education about HPV is key.

Application of a multiplex PCR to cervical cells collected by a paper smear for the simultaneous detection of all mucosal human papillomaviruses (HPVs) and typing of high-risk HPV types 16 and 18

A simple paper smear (PS) method for dry collection and storage of cervical specimens was employed to develop an easy multiplex (MPX) PCR for simultaneous detection of generic human papillomaviruses (HPVs) as well as typing of the high-risk HPV-16 and -18, the two clinically most important HPV genotypes, which are responsible for more than 80 % of cervical cancers. Multiplexing was performed with a small amount of DNA eluted by boiling from a single PS punch in a single tube and using a mixture of four pairs of primers specific for the HPV L1 consensus sequence, HPV-16, HPV-18 and the β-globin gene. Sixty HPV-positive biopsies and corresponding PS specimens from cervical cancer patients as well as cervical smears from 100 healthy women with or without abnormal cytology were collected both as PSs and in PBS. Detection of HPV DNA from cervical biopsies collected in PBS and corresponding cervical scrapes on a PS or in PBS by conventional and MPX-PCR showed a concordance of 100 % and adequacy of 93 %. A similar comparative study in cervical scrapes from normal women also revealed 100 % concordance. The technique was validated in a multicentric study at four different national laboratories. PSs collected by different centres showed variable adequacy (73-82 %) but the use of multiple PS discs for DNA extraction significantly increased the adequacy. Integration of PSs with MPX-PCR for the detection and typing of HPVs is a highly convenient, efficient, simple and cost-effective method for large-scale clinico-epidemiological studies and is also suitable for HPV vaccine monitoring programmes in resource-poor settings.

Knowledge and awareness about cervical cancer and its prevention amongst interns and nursing staff in Tertiary Care Hospitals in Karachi, Pakistan

Background and Objective

Cervical cancer is one of the leading causes of morbidity and mortality amongst the gynecological cancers worldwide, especially in developing countries. It is imperative for at least health professionals in developing countries like Pakistan to have a sound knowledge about the disease. This study was carried out to assess the knowledge and awareness about cervical cancer and its prevention amongst health professionals in tertiary care hospitals in Karachi, Pakistan.

Methods and Design

A cross-sectional, interview based survey was conducted in June, 2009. Sample of 400 was divided between the three tertiary care centers. Convenience sampling was applied as no definitive data was available regarding the number of registered interns and nurses at each center.

Results

Of all the interviews conducted, 1.8% did not know cervical cancer as a disease. Only 23.3% of the respondents were aware that cervical cancer is the most common cause of gynecological cancers and 26% knew it is second in rank in mortality. Seventy-eight percent were aware that infection is the most common cause of cervical cancer, of these 62% said that virus is the cause and 61% of the respondents knew that the virus is Human Papilloma Virus (HPV). Majority recognized that it is sexually transmitted but only a minority (41%) knew that it can be detected by PCR. Only 26% of the study population was aware of one or more risk factors. Thirty seven percent recognized Pap smear as a screening test. In total only 37 out of 400 respondents were aware of the HPV vaccine.

Conclusion

This study serves to highlight that the majority of working health professionals are not adequately equipped with knowledge concerning cervical cancer. Continuing Medical Education program should be started at the hospital level along with conferences to spread knowledge about this disease.

Novel missense mutation in FHIT gene: interpreting the effect in HPV-mediated cervical cancer in Indian women

Human papillomavirus (HPV) is considered to be a major etiological factor but is not sufficient for the development of cervical cancer. Other host factors including altered tumor suppressor gene activities might contribute to the carcinogenic process. Fragile Histidine Triad (FHIT) has been shown to play a pivotal role in carcinogenesis. Therefore, we made an attempt to find out point mutation of FHIT gene in HPV mediated cervical cancer in Indian women. 112 cases of cervical carcinoma tissue biopsies and 38 cervical scrapes samples of normal cytology were employed for this study. Herein, we report a novel mutation identified at nucleotide position 655, at codon 98 from CAT --> CGT with ultimate replacement of amino acid Histidine by Arginine in cervical cancer cases. Molecular modeling was performed to predict the effect of this mutation in disease pathology. We predict that this change, His to Arg substitution in substrate-binding domain may generate catalytically inactive protein with loss of tumor suppressor activity.

Transcription factor AP-1 in esophageal squamous cell carcinoma: alterations in activity and expression during human Papillomavirus infection

Background

Esophageal squamous cell carcinoma (ESCC) is a leading cause of cancer-related deaths in Jammu and Kashmir (J&K) region of India. A substantial proportion of esophageal carcinoma is associated with infection of high-risk HPV type 16 and HPV18, the oncogenic expression of which is controlled by host cell transcription factor Activator Protein-1 (AP-1). We, therefore, have investigated the role of DNA binding and expression pattern of AP-1 in esophageal cancer with or without HPV infection.

Methods

Seventy five histopathologically-confirmed esophageal cancer and an equal number of corresponding adjacent normal tissue biopsies from Kashmir were analyzed for HPV infection, DNA binding activity and expression of AP-1 family of proteins by PCR, gel shift assay and immunoblotting respectively.

Results

A high DNA binding activity and elevated expression of AP-1 proteins were observed in esophageal cancer, which differed between HPV positive (19%) and HPV negative (81%) carcinomas. While JunB, c-Fos and Fra-1 were the major contributors to AP-1 binding activity in HPV negative cases, Fra-1 was completely absent in HPV16 positive cancers. Comparison of AP-1 family proteins demonstrated high expression of JunD and c-Fos in HPV positive tumors, but interestingly, Fra-1 expression was extremely low or nil in these tumor tissues.

Conclusion

Differential AP-1 binding activity and expression of its specific proteins between HPV - positive and HPV - negative cases indicate that AP-1 may play an important role during HPV-induced esophageal carcinogenesis.

Recombinant measles virus-HPV vaccine candidates for prevention of cervical carcinoma

Cervical cancer is mainly associated with HPV genotype 16 infection. Recombinant measles virus (rMV) expressing HPV genotype 16 L1 capsid protein was generated by construction of an antigenomic plasmid, followed by rescue using the human "helper" cell line 293-3-46. In cell cultures the recombinant MV-L1 virus replicated practically as efficiently as the standard attenuated MV established as commercial vaccine, devoid of the transgene. The high genetic stability of MVb2-L1 was confirmed by 10 serial viral transfers in cell culture. In transgenic mice expressing the MV receptor CD46 the recombinant induced strong humoral immune responses against both MV and HPV; the antibodies against L1 exhibited mainly neutralizing capacity. Our data suggest that MV is a promising vehicle for development of inexpensive and efficient vaccines protecting from HPV infection.

Association between human leukocyte antigen class II alleles and human papillomavirus-mediated cervical cancer in Indian women

We investigated the association of human leukocyte antigen (HLA) II (DRB1 and DQB1) alleles with susceptibility to human papillomavirus (HPV)-associated cervical precancer and cancer cases in a hospital-based case-control study in a northern Indian population. A total of 202 subjects, including 100 patients comprising 31 cervical precancer (cervical intraepithelial neoplasia [CIN] 2/3) and 69 invasive cervical cancer cases, and 102 healthy controls participated in the study. Both patients and controls were screened for HPV infection using a polymerase chain reaction (PCR-based approach. Low-resolution PCR-sequence specific priming (PCR-SSP) was used to genotype HLA II (DRB1 and DQB1). Our results demonstrate that the DRB1*15 allele/DRB1*15-DQB1*06 haplotype may have a predisposition for HPV infection (p(c) < 0.05) or cervical cancer/precancer (p(c) < 0.05) development, whereas the DRB1*04 allele/DRB1*04-DQB1*03 haplotype might exhibit susceptibility to cervical precancerous lesions (p(c) < 0.05). The DRB1*13 allele/DRB1*13-DQB1*06 haplotype was strongly protective against risk to HPV infection (p(c) < 0.002) as well as cervical cancer (p(c) 0.01). Therefore, we have demonstrated that HLA DR-DQ polymorphisms are involved in genetic susceptibility to cervical cancer or HPV infection in a northern Indian population.