London: In what`s being claimed a medical breakthrough, scientists say they have developed a vaccine to treat breast cancer, using a patient`s own cells.
An international team says that tests on women revealed "promising" results, with 85 per cent of the patients with a ductal carcinoma in situ (DCIS), the most common non-invasive form of the disease, showing protection after four years.
In fact, in their tests, the scientists, led by the University of Pennsylvania, enrolled 27 women patients and isolated specialised white cells using standard techniques similar to blood donation.
The cells were manipulated in the laboratory to allow the immune system to recognise the cancerous cells as foreign and attack them. Each patient received four weekly injections of their personalised vaccine and had surgery two weeks later to remove any remaining disease.
The scientists compared pre-vaccination samples with post-vaccination samples and found five patients, almost 20 per cent, had no disease visible, indicating their immune
system had wiped out the tumour.
Of the remaining 22, damaging proteins had been eliminated in 11 and reduced by 20 per cent or more in another two, `The Daily Telegraph` reported.
"We are continuing to see this pattern in our second, ongoing trial," team leader Dr Brian Czerniecki said.
The scientists say the results provide new evidence therapeutic breast cancer vaccines may be most effective for early, localised disease, and when the treatment goes after a
protein critical to cancer cell survival.
Dr Czerniecki said: "I think these data more than prove that vaccination works in situations where the target is right. Previous vaccines targeted tissue antigens that were
expressed on the cancer cells, but were not necessary for tumour survival.
"So a vaccine response would cause the tumour to just stop expressing the antigen and the tumour would be fine. Here we are going after HER2/neu, which is critical for survival of early breast cancers. If we knock it out with the immune response, we cripple the tumour cells."
The findings have been published in the `Journal of Immunotherapy`.