London - Terminal breast cancer has been wiped out in “astounding” research that raises the hope of a cure.
In tests on mice, tumours that would normally prove fatal vanished for at least eight months.
This is the equivalent of 24 years for a woman and would be judged a lasting cure under current criteria. By contrast, existing treatments extend life by as little as six months.
US researchers said that even ifits only partly successful in people, the new therapy could transform treatment of the disease. Mauro Ferrari, president of the Houston Methodist Research Institute in Texas, said: “I would never want to over-promise to the thousands of patients looking for a cure but the data is astounding.”
However, British experts cautioned that what works in the lab doesn’t always help real patients and said more research is needed. Dr Ferrari’s focus is metastatic cancer, where the disease has spread from the breast to other parts of the body. While the initial tumour that appears on a woman’s breast rarely kills, once cancer attacks other parts of the body it becomes incurable.
Clinicians find it difficult to deliver drugs to tumours hidden deep in the lungs or liver and, once there, the medication can be pumped out by cells that have become resistant to treatment.
Dr Ferrari has found an ingenious way of getting round these defences - and so of potentially curing metastatic cancer.
He has taken a widely-used cancer drug called doxorubicin and packed it into microscopic discs made of silicon. The silicon packaging hides the drug from the cancer, allowing it to sneak into tumour cells. Once inside, the silicon is broken down, releasing the drug, which is in an inactive form. The drug then moves out of reach of the pumps that are poised to eject it and towards the very heart of the diseased cell.
Once there, the drug self-activates and the cell is killed. In tests on mice with terminal cancer, all the animals given conventional treatment died. By contrast, half of the creatures given the new treatment were still cancer-free after eight months.
About 11 700 women die of breast cancer in the UK each year, the majority of them after tumours have spread.
Dr Ferrari says that in future, women with metastatic breast cancer could be given an injection of billions of drug-filled silicon discs. This would home in on tumours and destroy them. He hopes to test the treatment on women next year, with some of the early trials in the UK.
Writing in the journal Nature Biotechnology, he added that he had only tried the technique against one type of breast cancer but he is optimistic it will also work against others: “If this research bears out in humans, we are talking about dramatically extending life.”
Stressing more work is needed, Dr Alan Worsley, of Cancer Research UK, said: “This study helps show that a new delivery system to release chemotherapy inside cells could make treatment safer and more effective.”
Baroness Delyth Morgan, of Breast Cancer Now, added: “While the results look promising in mice, there is still a long way to go before we will know if this technique could be an effective treatment for women.”
Daily Mail