Breast cancer vaccine trials planned
US researchers, optimistic after animal trials, say human testing could begin as soon as next year. Study author describes possibilities as ‘monumental’.
31st May 2010 - US researchers have developed a breast cancer vaccine which they say has prevented the condition in mice. If it is successful, it would be the first vaccine to prevent breast cancer.
The Cleveland Clinic’s Lerner Research Institute says a single jab with the antigen α-lactalbumin prevented tumours from forming in their animal studies. Registration for human trials could begin next year.
Their study is published online in the journal Nature Medicine ahead of appearing in the print edition in June.
Breast Cancer caused 12,116 deaths in the UK in 2008, 99% in women, 1% in men.
The study’s principal investigator, Dr Vincent Tuohy, says in a news release: “We believe that this vaccine will someday be used to prevent breast cancer in adult women in the same way that vaccines have prevented many childhood diseases.
“If it works in humans the way it works in mice, this will be monumental. We could eliminate breast cancer.”
The researchers used mice who were genetically prone to getting cancer. They gave one lot of mice a vaccine containing α-lactalbumin and another half with a vaccine that did not contain it.
None of the mice vaccinated with α-lactalbumin developed breast cancer, all of the others did.
There are already vaccines designed to prevent cancers by guarding against viruses which trigger cervical and liver cancer - human papillomavirus (HPV) and hepatitis B virus (HBV). The new jab is designed to prevent the formation of the breast cancer itself.
The researchers say their work is made more difficult because cancer itself is not seen as a ‘foreign invader’ which should be attacked like viruses.
Trying to prevent over-growth of cells would effectively be vaccinating against the person’s own body, destroying healthy tissue.
“Most attempts at cancer vaccines have targeted viruses, or cancers that have already developed,” says Dr Joseph Crowe, head of Cleveland Clinic’s breast cancer centre. “Dr Tuohy is not a breast cancer researcher, he’s an immunologist, so his approach is completely different - attacking the tumour before it can develop. It’s a simple concept, yet one that has not been explored until now.”
Tuohy says the key is to find a target within the tumour that is not usually found in healthy people.
α-lactalbumin is a protein that is found in most breast cancers, but is only found in healthy women when breast feeding.
The study team say the plan would be to vaccinate women over 40 when the risk of breast cancer increases. If a woman got pregnant after having the jab, breast soreness would be likely, so breastfeeding would not be possible.
The researchers say that for younger women with an increased risk of breast cancer, the vaccine could be an alternative to a precautionary mastectomy.
Tuohy believes that the findings also give an insight into developing vaccines to prevent other types of cancer.