The Department of Biotechnology (DBT) has initiated an integrated research programme for the development of an indigenous version of cervical cancer vaccine, which can prevent infection by the human papillomavirus (HPV), a sexually transmitted infection before it can cause cervical cancer.

The six institutes, which are part of the cervical cancer research, are Bangalore-based KMIO, New Delhi's All India Institute of Medical Sciences, Mumbai based Tata Memorial Hospital, Kolkotta's Chittaranjan Das Cancer Hospital, Vellore's CMC and Thiruvananthapuram's Regional Cancer Centre.

HPV infection is rampant in India and over 80 per cent of sexually active women could acquire a genital HPV infection. Persistent genital HPV infection could lead to a pre-malignant state known as cervical intraepithelial neoplasia (CIN), which could eventually progress to cervical cancer if left untreated. Kidwai registers about 1,500 cases of cervical cancer annually. In sharp contrast, on an average, only about 30 cases of CIN3 are registered every year.

"The primary reason for the DBT to start the research was to study the HPV genotypes that were responsible for the cervical cancer in India," stated Dr P Bapsy, director, KMIO, Bangalore.

The 125 cervical biopsy samples from each of the 6 centres identified in the country have been collected to know the frequency of genotypes prevalent in cases of cervical cancer. DNA has been extracted from 455 cases and genotyping performed by reverse line blot assay (RLBA), an in-house geno-tying method developed by Kidwai Memorial Institute of Oncology, Bangalore. This technology of genotyping HPV by multiplex PCR followed by RLBA has been handed over to a commercial firm. DNA samples from all the 6 centres are being genotyped by the commercial firm in a blinded fashion, stated Dr RS Jayshree, associate professor, department of microbiology, Kidwai Memorial Institute of Oncology, Bangalore.

Multiplex PCR/RLBA is a highly sensitive and objective test for picking up HPV infection and would surpass the conventional pap smear tests which is relatively insensitive and subjective. However, for making a diagnosis of CIN3 or cervical cancer, Pap smear examination would be required to confirm abnormal cells in the cervical scrapes. Sequencing of HPV 16 L1 and E6 and E7 regions are also underway.

Scientists at the Advanced Centre for Treatment, Research and Education, Mumbai have successfully made Virus Like Particles (VLP) which are empty shells with no viral genome and non-infectious in nature and highly immunogenic of L1 of HPV16 and the technology has since been transferred to a commercial company for large scale manufacture of these. Animal studies have also been completed to confirm the immunogenicity of these VLPs. Simultaneously, scientists from National Institute of Immunology have also successfully made capsomeres from HPV16 L1 in E.coli. These have further been purified. Animal studies are awaited.

Prophylactic HPV vaccines are proving to be effective in preventing persistent infection with HPV and protects against subsequent development of cervical cancer. Currently, there are two prophylactic vaccines developed by Merck's Gardasil (quadrivalent) and GlaxoSmithKline's Cervarix (bivalent) designed to target HPV types 16 and 18. These are priced around Rs 16,000 and not available in India as yet.

Cervix cancer is the fifth most common, second most widespread after breast cancer and third leading cause of deaths in women worldwide. Global incidence is 5.10 lakh new cases annually. India accounts for 1.32 lakh cases. Mortality rate world wide is 2.88 lakh and 74,118 deaths annually d in India. Risk factors are viral infections (HPV, HIV, HSV) and multiple sex partners along with low antioxidant diets. Lack of awareness results in high fatality as cases are diagnosed in the advance stages. Regular screening is the only prevention because chances of developing cervical cancer is approximately five times higher in those not regularly examined. India unfortunately doesn't have organized screening programmes, stated oncologists.