A vaccine would be a major breakthrough
Scientists have unravelled the body's immune response to a virus which causes most cases of cervical cancer.
They hope their work on the human papilloma virus (HPV) could aid efforts to develop a cervical cancer vaccine.
The research shows patients able to rid HPV from their system have a different immune response to those who cannot combat it and go on to develop cancer.
The study, by the University of Birmingham, was published in the British Journal of Cancer.
Cervical cancer is the second most common female cancer worldwide, with an estimated 500,000 new cases diagnosed each year. In 2002 the disease caused 1,120 deaths in the UK alone.
The Birmingham study, funded by Cancer Research UK, focused on 41 women, some who had HPV infection, and others with cervical cancer.
The researchers measured the response of immune system cells to proteins from the most common type of HPV.
Researcher Dr Jane Steele said: "We found that the patients with pre-cancerous lesions most likely to progress to cervical cancer showed less immune activity from a population of immune cells called helper T cells than the women who were at much less risk.
"This could mean that helper T cells, which are known to play a central role in the immune response, are critical in disease progression.
"Vaccines aimed to re-activate helper T cell responses to the relevant proteins should be considered."
Professor John Toy, medical director of Cancer Research UK, said: "Vaccines are likely to play an important role in helping us control certain cancers in the future and scientists are hopeful that vaccines against HPV might be able to prevent cervical cancer altogether.
"This research opens up new avenues of investigation for the development of possibly better vaccines."
There are more than 70 different types of HPV, of which only some are linked to an increased risk of cervical cancer.
The current study focused on HPV 16, which is present in up to 70% of cervical cancers.