WASHINGTON (AFP) - Botox has frozen the faces of countless Hollywood stars, and international researchers said the toxic injections might also be able to stop cancer in its tracks, at least temporarily.
The findings in the journal Science Translational Medicine are based on studies of mice with stomach cancer.
Researchers found that Botox could block signals from the vagal nerve - which extends from the brain stem to the abdomen - slowing the growth of tumours as much as surgery would.
"We found that by removing the effect of the nerve, the stem cells in the cancer tumour are suppressed, leading to cancer treatment and prevention," said co-author Duan Chen, a professor at the Norwegian University of Science and Technology.
Botox worked when injected locally to the vagus nerve by blocking the release of a neurotransmitter, acetylcholine, that encouraged the tumor to grow.
Other techniques - such as surgically cutting the vagus nerve and giving a blocking drug - also slowed tumour growth.
Blocking acetylcholine through facial injections lessens wrinkles by temporarily paralysing muscles.
"Scientists have long observed that human and mouse cancers contain a lot of nerves in and around the tumor cells," said Timothy Wang, professor of medicine at Columbia University's Herbert Irving Comprehensive Cancer Center.
"We wanted to understand more about the role of nerves in the initiation and growth of cancer, by focusing on stomach cancer."
A phase II clinical trial of the method in patients with stomach cancer is now taking place in Norway.
Scientists say the technique, while not a cure for cancer, might extend the lives of people with inoperable stomach cancer, or patients who no longer respond to chemotherapy.
"We believe this treatment is a good treatment because it can be used locally and it targets the cancer stem cells," said Chen.
Further research is needed to determine if the technique might work in other cancers.
Stomach cancer is the fourth most common type of cancer worldwide, and about one quarter of patients survive for more than five years after diagnosis.